Search

Dams play an important role in our society, but their negative impacts on aquatic ecosystems have led to a need for conservation efforts to mitigate the negative effects. In some instances, dam removal has been suggested to be the most economically and ecologically beneficial restoration method to improve longitudinal connectivity. This, however, has increased the need of more research about the effects dam removal have on aquatic ecosystems, since the outcomes of this restoration method can be unpredictable. In this study, I investigated ecological impacts of dam removals in Swedish inland waters. I collected field data from five different lakes in Värmland and Dalarna, two lakes with dam removal in 2017/2018 and three without. I studied how dam removal affected different trophic levels of the aquatic ecosystem, where I predicted that a top-down effect would increase abundances of piscivorous European perch (Perca fluviatilis) and zooplankton, but decrease phytoplankton, whereas a bottom-up effect would lead to increases in biomass at all trophic levels (with most pronounced effects on nutrient concentration). If both top-down and bottom-up effects would operate in parallel, all the above mentioned effects could occur. I also predicted that if dam removal affected the fish community, there would be a change in species diversity and fish biomass. Moreover, if perch demography was affected, there would be a change in perch length and abundance of different age classes. To investigate this, I collected data on fish, plankton, nutrients (P, N), DOC, pH and conductivity in the five lakes and compared this with already existing historical data using a BACI design. Two-way ANOVAs were used to study the effects of dam removals on these variables. There were not enough historical data on P concentration or zoo-and phytoplankton to be analyzed statistically. I did, however, conduct correlation analyses with zoo- and phytoplankton. Contradictory to my prediction, the results showed no effect of dam removal on fish biomass or diversity, water chemistry or perch demography in the studied lakes. There was, however, a statistically significant effect of time on Tot-N, with lower values after the years of 2017/2018 (regardless of dam removal). There were also some differences between the lakes in species diversity, concentration of Tot-N, potentially piscivorous perch and perch length. The outcomes of dam removal are unpredictable, as are the expected time-lapse of the effects, which means that changes may yet occur in the studied lakes. Knowledge about ecosystem responses to dam removal enables managers to better predict the effects of dam removal, and thereby facilitate decision makings related to this restoration method. Dammar spelar en viktig roll i vårt samhälle, men deras negativa påverkan på akvatiska ekosystem har ökat behovet av bevarandeinsatser för att minska de negativa effekterna. I somliga fall har dammutrivning föreslagits vara den mest ekonomiskt och ekologiskt gynnsamma bevarandemetoden för att förbättra longitudinell konnektivitet. Detta har dock ökat behovet av mer forskning gällande dammutrivningars effekter på akvatiska ekosystem, eftersom utfallen av denna bevarandemetod kan vara oförutsägbara. I denna studie undersökte jag dammutrivningars ekologiska effekter i svenska inlandsvatten. Jag samlade data i fält från fem olika sjöar i Värmland och Dalarna, två sjöar med dammutrivningar under 2017/2018 och tre utan. Jag undersökte hur dammutrivning påverkade olika trofiska nivåer i det akvatiska ekosystemet, med förväntningarna att en top-down-effekt skulle öka abundansen av fiskätande abborre (Perca fluviatilis) samt djurplankton, men minska växtplankton, medan en bottom-up-effekt skulle leda till ökad biomassa inom samtliga trofiska nivåer (men med mest effekter på näringskoncentration). Om både top-down- och bottom-up-effekter skulle verka parallellt kunde samtliga ovanstående nämnda effekter förekomma. Jag förväntade även att om dammutrivning påverkade fisksamhället skulle det ske en förändring i artdiversitet och fiskbiomassa. Därtill bör en effekt på demografi hos abborre leda till förändringar i abborrlängd- och abundans i olika åldersklasser. För att undersöka detta samlade jag in data över fisk, plankton, näringsämnen (P, N), DOC, pH och konduktivitet i de fem sjöarna och jämförde detta med redan existerande historiska data med en BACI design. Tvåvägs-ANOVAs användes för att studera effekterna av dammutrivningar på dessa variabler. Det fanns inte tillräckligt med historiska data över P-koncentration eller djur- och växtplankton för att analyseras statistiskt. Jag utförde dock korrelationsanalyser med djur- och växtplankton. I kontrast till min förväntan visade resultaten ingen effekt av dammutrivning på fiskbiomassa- eller diversitet, vattenkemi eller demografi hos abborre i de studerade sjöarna. Det var däremot en statistiskt signifikant effekt av tid på Tot-N, med lägre värden efter 2017/2018 (oberoende av dammutrivning). Det var även en del skillnader mellan sjöarna i artdiversitet, koncentration av Tot-N, potentiellt fiskätande abborre samt abborrlängder. Utfallen av damutrivningar är oförutsägbara, och detsamma gäller tidsintervallet för effekterna, vilket innebär att det fortfarande kan ske förändringar i de studerade sjöarna. Kunskap om ekosystemrespons till dammutrivning möjliggör för förvaltare att lättare bedöma effekter av dammutrivningar, och underlättar därav beslutsfattning relaterat till denna bevarandemetod.

Deep ecology seeks answers to and treats the earth's ecological crisis by digging down to the root of the problem. In deep ecology, an ecocentric worldview where human life is part of all living things is preferred over the anthropocentric view where humanity places itself at the center of the world. The purpose of this study was to investigate perceived interconnectedness with the rest of nature and how that connection affects possible environmental activism. Engagement can stem from various reasons and the study also examines whether or not it is based on the principles of deep ecology. With the intention to answer the study's research questions, a survey consisting of 18 questions was designed with both closed and open-ended answers, which enabled the use of both quantitative and qualitative analysis methods. The survey was distributed online, and data were collected from 95 individuals, 72% female and 28% male. The results showed that a 93% of the respondents see themselves as environmentally conscious people. A statistically significant majority agreed with the eight principles linked to the deep ecology movement, and it can therefore be assumed that these principles are at least partially accepted by environmentally conscious people. 55% of the respondents replied that the reason for their environmental activism is that they are committed to "nature of which we are all a part", this result is of interest regarding the focus on the ecocentric worldview in this study. The results show that a statistically significant majority agree that a stronger sense of connection with nature makes them want to make more environmentally conscious choices. This particular result encourages continued research of the subject, and a continuation of digging deeper for possible solutions to the ecological crisis. Djupekologin söker svar till, och behandlar, jordens ekologiska kris genom att gräva ner till roten av problemet. En ekocentrisk världsbild där människan är en del av allt levande föredras framför den antropocentriska bilden där människan sätter sig själv i centrum. Syftet med denna studie är att undersöka människans upplevda samhörighet med resten av naturen och hur den samhörigheten påverkar eventuellt miljöengagemang. Detta engagemang kan komma från olika anledningar och studien ville även undersöka huruvida det grundar sig i djupekologins principer eller ej. För att besvara studiens frågeställningar utformades en enkät bestående av 18 frågor med både slutna och öppna svarsalternativ, vilket möjliggjorde användandet av både kvantitativ och kvalitativ analysmetod. Enkäten distribuerades online och data samlades in från 95 individer, varav 72% kvinnor och 28% män. Resultatet visade att en majoritet av respondenterna, 93%, svarade att de ser sig själva som miljömedvetna människor. En signifikant majoritet instämde med de åtta principerna kopplade till den djupekologiska rörelsen och det kan därför antas att dessa principer är minst delvis godtagna av miljömedvetna människor. 55% av respondenterna svarade även att anledningen till deras miljöengagemang är att de engagerar sig för ”Naturen som vi alla är en del av”, detta resultat är av intresse med tanke på fokuset på denekocentriska världsbilden. Resultatet visar också att en signifikant majoritet svarar instämmande till att en starkare känsla av samhörighet med naturen får dem att vilja göra mer miljömedvetna val. I synnerhet detta resultat gör att studien uppmuntrar till fortsatt utforskning av ämnet, och till att gräva djupare efter lösningar till den ekologiska krisen.

Studien grundar sig i en designbaserad aktivitet, med syfte att bidra med kunskap om hur elever i lågstadiet upplever människans fem grundsmaker samt hur en praktisk aktivitet kan bidra till att öka förståelsen för människans smaksinne. Studien har en kvalitativ ansats, men med kvantitativa inslag i form av diagram för att tydliggöra resultat samt för att stärka analysen. Den kvalitativa analysen utgörs av transkribering med tillhörande diskussioner medan resultatet från den kvantitativa analysen var till för att synliggöra insamlade data utifrån samtliga elevers svar. Totalt har 52 elever i årskurserna 2 och 3, fördelade i 11 grupper, deltagit i studien. Aktiviteten spelades in för att sedan transkriberas och analyseras utifrån ett variationsteoretiskt perspektiv. Resultatet visar att eleverna tycks ha lättare för att uppfatta grundsmakerna sött, surt och salt medan grundsmakerna beskt och umami var svårare. Utan den praktiska aktiviteten i undervisningen hade det också varit svårt att synliggöra hur eleverna faktiskt upplever människans fem grundsmaker. The study is based on a design-based activity, with the purpose of contributing knowledge regarding how pupils in primary school experience the five basic flavors of human beings and how a practical activity can contribute to increasing the understanding of the human sense of taste. The study has a qualitative approach, but with quantitative elements in the form of diagrams to clarify results and to strengthen the analysis. The qualitative analysis consists of transcription with associated discussions, while the results from the quantitative analysis are to visualize collected data based on all the students´ answers. A total of 52 pupils in the grades 2 and 3, divided into 11 groups, participated in the study. The activity was recorded to later be transcribed and analyzed from a variation theory perspective. The results show that the pupils seem to find it easier to perceive the basic flavors sweet, sour and salty while the basic flavors bitter and umami are more difficult. Without the practical activity in the teaching, it would also have been difficult to make visible how the pupils actually experience the five basic flavors.

The riparian zone is a changeable and species-rich habitat with important ecological functions that have long been affected by human activities such as hydropower and forestry. Rivers and their adjacent riparian zones also constitute a transport route for plant parts and seeds in a form of passive transport, called hydrochory, which can contribute to the establishment of plants or the preservation of diversity in the riparian zone. Theories such as "the river collector hypothesis" state that the diversity of plants increases with distance from the source of a river and this study aims to investigate a specific part of this theory, namely the effect of tributaries on the accumulation of plants in the riparian zone. Plant surveys have been carried out upstream and downstream of the outlets of several tributaries to Vindelälven (unregulated) and Umeälven (regulated) in Västerbotten County, Sweden, to compare these locations with each other. Species numbers and effective species numbers for upstream and downstream surveys were analysed using paired t-tests with the expectation that both species numbers and effective species numbers would be higher downstream of tributaries than upstream. The results showed no significant differences between the upstream and downstream inventories. When examining the data, there was an indication of a trend of higher species numbers and effective species numbers downstream of tributaries in the Umeälven, but further research is needed to investigate possible connections. The explanation of the effect of tributaries on the diversity of plants in the riparian zone may be more complicated than can be explained only by theories of the accumulation of plants from hydrochory. Alternatively, the effect from the tributaries is small in relation to the longitudinal build-up of plants that occurs in longer free-flowing stretches of the rivers, which may hide the effect of the tributaries. Strandzonen är ett föränderligt och artrikt habitat med viktiga ekologiska funktioner som under lång tid har påverkats av mänskliga verksamheter som vattenkraft och skogsbruk. Älvar och dess angränsande strandzoner utgör även en transportsträcka för växtdelar och fröer i en form av passiv transport, benämnd hydrochori, som kan bidra till etableringen av växter eller bevarandet av mångfalden i strandzonen. Teorier som ”the river collector hypothesis” säger att mångfalden av växter ökar med avstånd från källan i en älv och den här studien har som mål att undersöka en specifik del av denna teori, nämligen vilken effekt biflöden har på ansamlingen av växter i strandzonen. Växtinventeringar har genomförts uppströms och nedströms om flera biflödens utlopp till Vindelälven (oreglerad) och Umeälven (reglerad) i Västerbottens län för att jämföra dessa lokaler med varandra. Artantal och effektivt artantal för uppströms- och nedströmsinventeringar analyserades med parade t-tester med förväntningen att både artantalet och det effektiva artantalet skulle vara större nedströms om biflöden än uppströms. Resultaten visade inga signifikanta skillnader mellan uppströms- och nedströmsinventeringarna. Vid granskning av data fanns en antydan till en trend med större artantal och effektivt artantal nedströms om biflöden i Umeälven men ytterligare undersökningar behövs för att utreda eventuella samband. Förklaringen till vilken effekt biflöden har på mångfalden av växter i strandzonen kan vara mer komplicerad än att det på egen hand kan förklaras med teorier om ansamling av växter från hydrochori. Alternativt är effekten från biflödena liten i relation till den longitudinella uppbyggnaden av växter som sker i längre fritt flödande sträckor av älvarna vilket skulle kunna dölja biflödenas effekt.

Denna studie handlar om elevers kunskap om evolutionära mekanismer och hur biologilärare utformar sin pedagogik för att stärka elevers begreppsmässiga förståelse. Studien består av fem semistrukturerade intervjuer med gymnasielärare i biologi vid två svenska gymnasieskolor. Studien lägger särskilt fokus på active learning-pedagogik och undersöker huruvida active learning kan främja elevers förståelse för evolutionära kärnbegrepp (variation, selektion och ärftlighet). Studiens resultat indikerar att de vanligaste missförstånden är att individer kan anpassa sig för att överleva, att begreppet fitness biologiska innebörd misstolkas samt en bristande förståelse för begreppet selektionstryck. Studien sätter förståelsen för evolutionära kärnbegrepp i relation till så kallade tröskelbegrepp som är utgör viktig förförståelse samt kognitiva biaser vilka utgör vanliga hinder för att kunna ta till sig kunskap om evolutionära mekanismer. Studien kontextualiserar active learning med närliggande didaktiska teoribildningar såsom Piagets begrepp ackommodera och det övre stegen i Blooms taxonomi. Ett resultat är att de lärare som själva har ett intresse av evolutionsundervisning i större utsträckning utvärderar sin undervisning och aktivt söker nya, mer illustrativa laborationer och övningar. Eftersom undervisningens utformning skiljer sig betydligt lärare emellan föreslås skapande av ett forum där evidensbaserade active learning- övningar kan tillgängliggöras för alla biologilärare. En active learning-laboration som baserat på forskning visat goda resultat beskrivs i detalj och jämförs ingående med en laboration genomförd av tre av de 5 intervjuade lärarna. Båda dessa laborationer utgör exempel på active learning-pedagogik, vilket skulle kunna utgöra en källa till inspiration som biologilärare kan använda för vidareutveckling av sin egen undervisning.

Sexual antagonistic selection is when an allele is favorable to one sex but harmful tothe other sex. Sexual antagonism is very common in nature and occurs among manyspecies. Although sexual antagonism plays an important part in evolution, today weknow very little about the mechanisms that contribute to this phenomenon and veryfew antagonistic locus have been identified. A study examining Drosophilamelanogaster was conducted to find out which locus was associated with sexualantagonism. Several candidates were identified. One of these candidates was the geneCG3598. This study aims to test and confirm whether there is a sexual antagonisticeffect in the locus of the gene CG3598 as a former study predicted. The hypothesis isthat the two alleles of CG3598 will show a sexual antagonistic effect on fitness. To dothis, two experiments were performed, one for D. melanogaster males and one forfemales. The tests were to measure the difference in reproduction of D. melanogasterbetween the two different allele variants that were previously created using theCRISPR/Cas9 technique in a new wild-type background. The two different variantsfor both males and females mated with wild type variants in separate vials and thenwe counted which allele had managed to reproduce the most. The results showed thatthere was a significant difference between the two alleles for males but not forfemales. This means that one allele was better for male reproduction then the other.However, from this test you cannot conclude what made them better. For thefemales, there was a big difference between the test groups, which was not expectedand suggests that something may have gone wrong during the tests. The conclusion isthat there is a difference in fitness in the two alleles of CG3598 for males, however, itis not possible to confirm the hypothesis of a sexual antagonistic effect. Sexuell antagonistisk selektion är när en allel är gynnsam för ena könet men skadligför det andra könet. Sexuell antagonism är mycket vanligt i naturen och förekommerbland många arter. Även fast sexuell antagonism spelar en viktig del inom evolutionvet vi idag mycket lite om mekanismerna som bidrar till detta fenomen och väldigt fåantagonistiska lokus har identifierats. En tidigare studie undersökte Drosophilamelanogaster för att tar reda på vilken lokus som var associerad med sexuellantagonism. Dem kom fram till ett flertal kandidater, en av dessa kandidater vargenen CG3598. Denna studie går ut på att testa och bekräfta om det finns en sexuellantagonistisks effekt vid lokusen av genen CG3598 som tidigare studie förutspått.Hypotesen är att dem två allelerna av CG3598 kommer visa en sexuell antagonistiskeffekt på fitness. För att göra detta utfördes två experiment, ett för D. melanogasterhanar och ett för honor. Testerna gick ut på att mäta skillnaden i reproduktion hos D.melanogaster mellan de två olika allel varianter som var tidigare skapade medCRISPR/Cas9 tekniken i en ny vildtyp bakgrund. Jag lät dem två olika varianternabåde för hanar och honor para sig med vild typs varianter i separata provrör för attsedan räkna vilken allel som lyckats reproducera sig mest. Resultatet visade att detfanns en signifikant skillnad mellan dem två allelerna för hanar men inte hos honor.Detta betyder att ena allelen var bättre för hanars reproduktion en den andra. Dockkan man inte från detta test av göra vad det är som gör att dem är bättre. För honornavar det stor skillnad mellan testgrupperna vilket inte var förväntat och tyder på attnågot kan gått fel under testerna. Slutsatsen är att det finns en skillnad fitness hos dettvå allelerna av CG3598 för hanar, dock går det inte att bekräfta hypotesen för ensexuell antagonistisk effekt.

Biologi är ett stort ämne i naturvetenskap där läran om människokroppen inkluderas. Men på vilket sätt får barnen i förskolan lära sig om människokroppen? En viktig kompetens att få vetskap om i förskolan är människokroppens funktion för att må bra som människa. Syftet med studien är att belysa förskollärares erfarenheter av och syn på att främja barns lärande om och med kroppen genom fysisk rörelse. Metoden som använts är semistrukturerade intervjuer där sex förskollärare deltog från en kommun i Mellansverige. Resultatet i studien visar att förskollärare arbetar med människokroppen i olika aktiviteter med barnen genom deras intresse och frågor. Att redogöra för hur kroppen fungerar i olika aktiviteter är svårt anser förskollärarna. De arbetar för att synliggöra glädjen som den fysiska rörelsen medför. Utifrån studiens resultat och slutsatser framkommer det att förskollärarna anser vad betydelsefullt arbete med människokroppen är då den finns med oss hela livet. Förskollärarna anser även att genom rörelse får barnen utforska omvärlden där de berikas med nya erfarenheter. Implikationer för verksamheten blir att redan i förskolan berika barnen med kunskap om vad som behövs för att gynna människans mående. Arbetet handlar om att hitta rörelseglädje, bevara nyfikenheten och skapa förutsättningar för alla barn att kunna ta del av upplevelser genom utforskandet tillsammans.

Försvarsmekanismer är vanligt förekommande svar på predation och aggression bland djur. Till exempel uppvisar många terrestra sniglar en högre aktivitet och förändrat rörelsemönster när de identifierar kemiska signaler från predatorer. I denna studie undersökte jag hur kemiska signaler från en attackerad artfrände påverkade försvarsbeteenden hos trädgårdssnigel (Arion distinctus), där pantersnigel (Limax maximus) representerade aggressor. Ett laboratorieexperiment utfördes med fyra behandlingar (totalt 48 replikat): med slemspår av en trädgårdssnigel, med spår av en pantersnigel, med spår av båda arter tillsammans, samt utan spår. Jag förutspådde att spår av en attackerad artfrände (det vill säga spår från båda arter tillsammans) skulle medföra högre aktivitet och undvikande beteende hos trädgårdssnigeln, samt att båda arter under förberedelsen för behandlingarna skulle uppvisa en högre aktivitet vid närvaro av den andra arten än ensamma. Resultaten visade ingen signifikant effekt av behandling på trädgårdssniglarnas aktivitet eller rörelsemönster, eller på någon av arternas aktivitet vid närvaro av varandra. Eftersom sniglars försvarsbeteenden är kostsamma, är det möjligt att pantersnigeln inte utgjorde ett tillräckligt stort hot för att det skulle vara fördelaktigt för trädgårdssnigeln att utföra dessa beteenden. Defence mechanisms are a common response to predation and aggression in animals. For example, many terrestrial slugs exhibit a higher activity and change their movement patterns when identifying chemical signals from predators. In this study, I examined how chemical signals from an attacked conspecific affected the defence mechanisms of the common garden slug (Arion distinctus), where the leopard slug (Limax maximus) represented the aggressor. A laboratory experiment was conducted with four treatments (48 replicas in total): with mucus trails from a common garden slug, with trails from a leopard slug, with trails from both species together, and without trails. I predicted that trails from an attacked conspecific (i.e. trails from both species together) would result in increased activity and an avoiding behaviour in the common garden slug, and that both species during the preparation for the treatments would exhibit an increased activity in presence with the other species than alone. The results showed no significant effect of treatment on the common garden slug’s activity or movement pattern, or on both species’ presence of each other. Because slugs’ defence mechanisms are costly, it is possible that the leopard slug did not pose a threat big enough to be beneficial for the common garden slug to execute these behaviours.

Since the middle of the 20th century, scientists have observed that marine organisms ingest plastics in various shapes, directly or through food. Plastics smaller than 5 millimetres, called microplastics, have in recent years gained more attention and been found to accumulate environmental toxins. A family of organisms which have been found to ingest microplastics is Gammaridae, which are important as food sources and detritivores in many ecosystems. In this study, the occurrence of microplastics in marine gammarids was investigated in three rural and three urban areas, along the coast of Halland and northern Skåne. The aim was to find out if these organisms contain microplastics and to compare the occurrence in rural versus urban areas. Microplastics were found in 33 (approx. 14.9 %) of 221 samples, ranging from 0 to 3 microplastics per individual. A significant difference in the average amount of microplastics per individual was found between the rural and urban areas; the urban areas had a higher average, with one exception. In other studies, urban areas have been found to often contain more microplastics than rural areas, increasing the possibility that organisms in these areas ingest plastics. With more boat traffic and inhabitants in general, along with streams transferring plastics from inland areas, the amount of emissions in urban areas can be greater than in rural parts. The result shows that microplastics occur in marine gammarids in the 3 examined areas and that these organisms therefore may have an important part in the transfer of microplastics between trophic levels. Sedan mitten av 1900-talet har forskare observerat att marina organismer tar in plaster i olika former, direkt eller via föda. Plastpartiklar mindre än 5 millimeter, så kallade mikroplaster, har på senare år fått större uppmärksamhet och har också visat sig kunna ackumulera miljögifter. En familj av organismer som man funnit mikroplaster i är tångmärlor (Gammaridae), vilka i många ekosystem är viktiga som födokällor och nedbrytare. I denna studie undersöktes förekomsten av mikroplaster i marina tångmärlor på tre lokaler i stadsområden respektive landsbygdsområden, längs Hallandskusten och Skånes norra kust. Syftet var att se ifall dessa organismer innehåller mikroplaster samt jämföra förekomsten i landsbygdsområden kontra stadsområden. Av 221 analyserade prov förekom mikroplaster i 33 (ca 14,9 %) och förekomsten per individ varierade från 0 till 3 mikroplaster. En signifikant skillnad i medelvärde av mikroplaster per individ fanns mellan landsbygdsområden och urbana områden; urbana områden innehöll i genomsnitt mer men med ett undantag. I andra studier har man funnit belägg för att stadsområden ofta innehåller mer mikroplaster än landsbygdsområden, något som ökar risken för att organismer i dessa områden tar in plaster. Med mer båttrafik och antal invånare överlag, tillsammans med vattendrag som för med sig plast från inlandet, kan det i dessa områden ge en större utsläppsmängd i jämförelse med i landsbygdsområden. Resultatet visar på att mikroplaster förekommer i marina tångmärlor i de undersökta områdena och att dessa organismer därmed kan vara en viktig del i överföringen av mikroplaster mellan trofiska nivåer.

The forest area in which this biotope survey was executed is located east of Mjälahult, in the county of Hylte. East of the area lies the lake Stora Allgunnen, which is part of the main catchment area of Nissan and contains perch, bream, pike, whitefish and pike-perch. The examined forest is a deciduous forest consisting of beech and oak, with elements of birch, rowan, hazel, spruce, and pine. There are signs that the forest was formerly used as a pasture, with old stone walls surrounding the entire area and an old road crossing the middle of the forest. The area consists of a lot of moss-covered stones, stone cairns, dead wood, beard lichens and signs from great spotted woodpecker. The main purpose of this biotope survey is to evaluate biotopes that are of value for biodiversity, in order to protect valuable nature. This biotope survey has been executed according to the national Swedish standard for biodiversity surveys (SS 199000:2014), with an addition for value elements. During the inventory, four different biotopes were identified - mixed forest, beach forest, mixed swamp forest and noble deciduous forest. Two biotopes were identified as biotopes of considerable biotope value - mixed swamp forest and noble deciduous forest. The third biotope - beach forest was identified as a biotope of certain biotope value. Parts of the area - mixed forest, was identified as a biotope of no considerable biotope value. Even though only two of four biotopes have a considerable biotope value, the objects that have a significant value cover large areas of the forest, which raises interest in preserving and protecting the entire forest in the long term, considering that it will promote biodiversity in the future. Ögärdet skog ligger öster om Mjälahult i Hylte kommun. Öster om skogen ligger sjön St. Allgunnen, vilken ingår i Nissans huvudavrinningsområde och där man bland annat kan hitta abborre, braxen, gädda, sik och gös. Den inventerade skogen är en ädellövskog som består av bok och ek, med inslag av björk, rönn, hassel, gran och tall. Det finns tecken på att området förr har använts som betesskog med gamla stenmurar som inhägnar området. Det finns även tydliga tecken på en gammal väg som korsar den nuvarande grusvägen och in i skogen. Området består av mycket mossbeklädda stenar, stenrösen, död ved, skägglavar och spår från större hackspett. Det huvudsakliga syftet med denna biotopinventering är att värdera biotoper som är utav värde för biologisk mångfald, samt för att utveckla ett skydd för dessa biotoper. Arbetet är utfört enligt SIS standard (SS 199000:2014), med tillägg värdeelement. Under inventeringen identifierades fyra olika biotoper – blandskog, strandskog, blandsumpskog och ädellövskog. Två biotoper identifierades med ett påtagligt biotopvärde, vilka var ädellövskog och blandsumpskog. Den tredje biotopen som identifierades var strandskog, vilken bedömdes ha ett visst biotopvärde. Delar av området identifierades även till biotopen blandskog, vilka bedömdes ha ett obetydligt biotopvärde. De värdeelement som påträffades täcker stora ytor av skogen och har ett högt naturvärde, vilket ger upphov till ett intresse att bevara och skydda skogen långsiktigt med förutsättning att den i framtiden kan gynna biologisk mångfald.

Gymnasieelevers förståelse av naturligt urval och fylogenetiska träd har undersökts genom en enkätundersökning med 223 elever på fyra gymnasieskolor i Sverige. Resultatet från studien visar att elever oftare svarar rätt på flervalsfrågor med evolutionära träd än på frågor som behandlar naturligt urval. Det skulle kunna vara för att de frågor (och svar) som tar upp naturligt urval har mer text, där den relevanta informationen måste kunna tas ut först från frågan och sedan från svarsalternativen för att kunna välja det rätta alternativet. Resultatet visar även att det inte finns något samband mellan elevernas förståelse av evolutionära träd och naturligt urval. Eleverna kan alltså förstå det ena (evolutionära träd) men behöver inte nödvändigtvis förstå det andra (naturligt urval) och vice versa. High school students understanding of natural selection and phylogenetic trees has been tested through a survey of 223 pupils in four upper secondary schools in Sweden. The results of the study show that students more often choose the correct answer on multiple choice questions with evolutionary trees than on questions that address natural selection. One reason for this could be that the questions (and answers) that address natural selection have more text, where the students must be able to take out the relevant information first from the question and then from the answers, in order to be able to choose the correct answer. The result also shows that there is no connection between the students understanding of evolutionary trees and natural selection. The pupils can thus understand one (evolutionary trees) but do not necessarily need to understand the other (natural selection) and vice versa.

Syftet med studien är att undersöka hur förskollärare arbetar med människokroppen i förskolans äldrebarnsgrupper, 3 till 5 års ålder och vilka läroplansmål de kopplar till detta arbete. Metoden som användes var semistrukturerade intervjuer med ett förutbestämt frågeschema. Jag intervjuade sex förskollärare. Resultatet blev att arbetet kring människokroppen var nästintill enbart utformat utifrån barnens egna frågor och funderingar. Jag fick även reda på genom intervjuerna att arbetet kring människokroppen finns där men ett medvetet tankesätt kring det saknas. Både forskning och Läroplanen för förskolan (2016) stödjer att naturvetenskap, mer specifikt människokroppen, bör finnas som ett arbetsområde i förskolan.

The purpose of the study was to investigate preschool teachers´views of recycling in preschool. Eight preschool teachers were interviewed. Four of them worked in relatively newley-started prescools and four teachers in preschools that have existed for several decades. The result showed that the preschool teachers do not work so much intentionally with recycling, but still some recycling were included in their work. The teachers in the newer preschools work less with recycling than the older ones. There were shared opinions among the educators regarding their own interest in recycling and the attitude towards it. However, all prescools teachers agreed that recycling is important for the preschool, since it is in preschool that all learning begins. Lack of time and lack of conditions were some of the reasons the educators stated for not working with recycling. It might as well be a lack of intrest among preschool leaders. Studiens syfte var att undersöka vad pedagogerna anser om återvinning i förskolan. För att ta reda på detta intervjuades åtta förskollärare. Fyra av förskollärarna arbetade i relativt nystartade förskolor och fyra arbetade på förskolor som funnits i många årtionden. Förskollärarna var i olika åldrar och hade olika lång erfarenhet i yrket. Resultatet visade att på de förskolor jag gjort min undersökning arbetar de inte mycket på ett medvetet sätt med återvinning, däremot gör de det utan att tänka på att det är återvinning. De nyare förskolorna arbetar mindre med återvinning än de äldre. Det var delade meningar bland pedagogerna angående deras eget intresse för återvinning samt arbetslagets inställning till det. Däremot var samtliga pedagoger överens om att återvinning är viktigt att ha med i förskolan, då det är förskolan som lägger grunden för allt lärande. Tidsbrist och brist på förutsättningar var några av anledningarna pedagogerna uppgav till att de inte arbetar med återvinning. En annan orsak kan vara brist på intresse hos förskolecheferna.

The aim of this study was to illustrate what knowledge 6-year old’s in preschool have about plants. In all, ten children from two different preschools participated in the study. Qualitative interviews were used to get as much information as possible considering that 6-year old children have not developed their ability to read or write properly yet. It is easier for children to reason verbally than respond to a survey. The interviews with showing 20 images of regular Swedish plant species. The children were asked follow-up questions from what they told me about the plants on the images. The results showed that the children in the study knew very little about plant species, the most well-known plant was buttercup. The children knew more about plants living conditions and functions than species. The results also showed that some of the children in the study expressed a higher interest for interactive digital games than learning about plants.

Biology is a broad subject within the frame of natural science education. It includes the study of the smallest components of the cell to the process of energy movement between ecosystems. This study intended to examine how students in upper secondary school perceive biology education with their interest for the subject as a starting point. The study aimed toward the questions regarding what parts of the subject the students experience as meaningful and in what degree the contents of the syllabus are achieved into manageble knowledge and skills through the teacher. The study found that students experience high degree of learning interest the more the subject matter is relateble with their daily life out of school. The transmission of understanding was also fascilitated by the discourse of laboratory work, since its workflow visually verify many processes in biology. Students' approach to biology are influenced by their degree of intrerest towards the different parts of the subject. This varied commitment therefore require didactic skills from teachers, as well as awareness regarding what and how students wish to learn.

Trots att vuxenskolan har en stor andel andraspråkselever och kursplanerna betonar kommunikativa färdigheter, uttrycker inte läroplanen tydligt vilket uppdrag lärarna har för elevernas språkutveckling. Studien syftar därför till att belysa hur vuxenutbildningens biologilärare ser på sin yrkesroll i relation till språkutvecklande undervisning, samt vilken betydelse de menar att språket har för att lära sig biologi.Att lära sig biologi på gymnasienivå, kräver inte bara att eleven lär sig ämnesbegrepp, utan även hur språket används i en naturvetenskaplig kontext. Språkutvecklande undervisning har inte bara visat sig effektivisera ämneslärande, utan är en viktig förutsättning för detsamma. Individen och samhället har därför mycket att vinna på om lärarna använder sig av undervisningsstrategier vilka stöttar vuxna elevers språkutveckling. Inga tidigare studier har undersökt yrkeserfarna vuxenlärares uppfattningar om språkutvecklande undervisning och vilken betydelse de anser att språket har för kunskapsutveckling i biologi.Åtta biologilärare inom vuxenutbildningen medverkade i var sin semi- strukturerad intervju. Intervjutranskripten har kodats, kategoriserats och tematiserats med en kvalitativ innehållsanalys enligt Graneheim och Lundmans (2004) definition. Studien är teoretiskt förankrad i Vygotskijs sociokulturella teori. Resultaten visar att lärarna har goda kunskaper om betydelsen och behovet av att integrera kortare språkutvecklande aktiviteter i undervisningen.Förutsättningarna för detta är dock begränsade till följd av tidsbrist. Majoriteten av lärarna ser sig främst vara ämneslärare och att eleven redan ska ha tillräckligt goda språkkunskaper när de börjar läsa biologi på gymnasial nivå. En uppfattning som speglar vuxenskolans läroplan (Skolverket, 2012c). I praktiken har dock vuxenutbildningens uppdrag förändrats (Öst, 2014). Lärarna menar därför att det finns ett ökat behov av språkutvecklande aktiviteter inom undervisningens ram hos eleverna.

Denna studie handlar om hur lärare och elever uppfattar bilder i biologiböcker i grundskolans senare del utifrån ett normkritiskt perspektiv. Mer konkret har jag undersökt på vilket sätt lärare beskriver att de använder bilder i biologiböcker och på vilket sätt elevernas bakgrund påverkar vilken information de utläser ur bilderna. Den metod som användes var semistrukturerade kvalitativa intervjuer med tre lärare i grundskolan samt en enkätundersökning med 59 elever i årskurs nio. Studien visar att lärarna använder bilder i biologiboken med varierande medvetenhet och att de tror att det inte är någon större skillnad i hur de elever som uppfattar sig som tjejer respektive killar tolkar bilderna. Studien visar dock att elevernas uppfattade kön spelar roll. De elever som uppfattar sig som tjejer kan ange fler relevanta ord för bilderna i läroboken och läser in sakliga och negativt laddade begrepp kring män i bilderna för sex och samlevnadskapitlet, medan de som uppfattar sig som killar läser in fler negativt laddade ord kring kvinnor för dessa bilder. När de gäller bilden som föreställer Carl von Linné associerar de elever som uppfattar sig som killar i större utsträckning till naturvetenskapliga forskare eller till historiska manliga personer som inte har koppling till bilden. Överlag tolkar eleverna bilderna bokstavligt samt associerar till ord som inte alltid har med bilden att göra. Slutsatsen är att lärarna är delvis medvetna om behovet av stimulerande bilder för eleverna men att lärarna behöver mer kunskap om hur olika elever uppfattar de bilder som används i undervisningen, så att lärarna kan komplettera bilderna i läroboken med bilder som utmanar heteronormativa begrepp, traditionella könsmönster och synen på biologin som en vetenskap för västerländska män.

Syfte: Syftet med detta examensarbete är att kartlägga förkunskaperna i områdena fotosyntes, biologisk mångfald, växthusgaser, energi och hållbar utveckling, samt evolution och naturligt urval hos gymnasieelever som läser ämnet Biologi 1 på det naturvetenskapliga programmet på en gymnasieskola i västra Götaland. Syftet är också att utvärdera betydelsen av diagnostiska test för dessa elever och deras lärare. Avsikten är även att presentera möjliga förslag till att utnyttja resultaten av dessa test för att på bästa sätt kunna hjälpa de elever som har svårigheter i eller ligger i riskzonen för att ha svårigheter i dessa kunskapsområden i Biologi.Metod och genomförande: Undersökningen har dels genomförts med en diagnostisk test, dels genom intervjuer av tre lärare på gymnasieskolan. Eleverna har även fått två analysfrågor som berörde deras uppfattningar om användandet av denna test inom ämnet Biologi.Resultat: Resultatet visar att eleverna har bristande förkunskaper inom områdena fotosyntes och betydelse av växthusgaser. Både elever och intervjuade lärare är positivt inställda till diagnostisk test i Biologi. Eleverna anser att diagnostisk test med fördel kan införas så länge dessa används för kartläggning av elevernas förkunskaper, samt som ett verktyg för att ge dem individuellt stöd till vidare kunskapsutveckling. Trots att lärarna verkar ha skilda uppfattningar om inflytandet av den eventuella diagnostiska testen på undervisningens upplägg och arbetsformer, tycker samtliga att nivågrupperingar inte är någon givande arbetsform, en mer blandad kunskapsnivå i grupper är ett mer effektivt sätt att hjälpa de elever som har bristande förkunskaper. Dessutom räknas språk och läsförståelse som viktiga faktorer för lärandets framgång.

Examensarbetet handlar om en jämförelse av Sveriges och Tysklands skolsystem på gymnasienivå. Syftet är, att utifrån ett lärarperspektiv analysera hur de två olika skolsystemen påverkar undervisning i ämnet biologi. Jämförelsen är baserad på båda ländernas styrdokument samt informationsmaterial som finns allmänt tillgänglig på myndigheternas informationsplattformer och stöds med lärarintervjuer som genomfördes i gymnasieskolor i Sverige och i Tyskland. Den största skillnaden är att Tyskland har ett centralstyrt utbildningssystem där ansvaret ligger på delstaternas regering medan ansvaret för utbildningen i Sverige ligger på varje enskild kommun. En stor skillnad finns i båda ländernas slutexamen. Det tyska ”Abitur” som ger högskolebehörighet är ett helhetsbetyg av alla kurser som ingår i antagningskraven under de sista två åren och prestanda i slutexamen. I motsats till det tyska systemet finns inget slutprov eller slutexamen i den svenska ”studenten”. Resultat visar att elevernas och lärarnas förutsättningar från tyska Sekundarstufe 1 och svenska grundskolan skiljer sig signifikant. I Sverige ingår ämnet biologi i det naturvetenskapliga programmet som är en av sex högskoleförberedande utbildningar på gymnasienivå. I Tyskland är biologi ett av fyra möjliga naturvetenskapliga ämnen som ingår i ”Abitur”. I den svenska biologiundervisningen satsar man på en kombination av teori och praktik medan utbildningen i Tyskland är mestadels teoretisk. Den svenska ämnesplanen fokuserar på att förmedla ämnets bredd medan den tyska ämnesplanen fokuserar på specifika områden som undervisas på djupet. Gymnasieskolor i Sverige erbjuder elevdatorer och har ett intranät där kommunikation mellan lärare och elever sker utanför klassrummet. Detta är ganska ovanligt i Tyskland. Däremot är alla läroböcker som används i skolan granskade av skolministeriet som är inte fallet i Sverige. I slutet av studien diskuteras om det borde vara möjligt att överföra en styrka från ett skolsystem till det andra skolsystemet.

I detta arbete har gymnasieutbildningens förändring från 1970 till idag undersökts. Som utgångspunkt för undersökningen har biologiämnet studerats. Under tiden från 1970 till idag har två läroplaner gällt (Lgy 70 och Lpf 94) och i år börjar en tredje att gälla (Gy 11). Genom att studera läroplaner kan man få en känsla över vad som är syftet med undervisningen och vilken typ av undervisning som förordas. Detta kan beskrivas med hjälp av olika läroplanskoder. Eftersom lärare sedan tolkar och realiserar läroplanerna, kan de förmedla ett annat innehåll och syfte i klassrummet. Den syn som förmedlas kallas följemening.Jag har analyserat gymnasieutbildningens förändring utifrån tre olika infallsvinklar. 1: de generella läroplanstexterna har jämförts och läroplanskod har bestämts. 2: kursplanerna och ämnesplan har analyserats utifrån ämnesfokus och kunskapsemfaser. 3: några erfarna lärare har intervjuats för att ge en bild av hur de har uppfattat förändringarna som skett.I studien har jag funnit att de generella läroplanstexterna och kursplaner väl speglar varandra. Resultatet visar att efter en fokusering på en moraliskt tillämpad undervisning i Lpf 94 så har vi nu en viss återgång till en mer rationell skola med praktiskt tillämpad undervisning i och med Gy 11. Den moraliskt tillämpade undervisningen finns kvar tillsammans med en disciplinär undervisning, som traditionellt verkar vara dominerande i naturvetenskaplig utbildning.Lärarintervjuerna visar att det är lärarens visioner och intressen tillsammans med elevinteraktionen som styr vad som förmedlas i klassrummet snarare än läroplanen.

Med en ständigt ökande stoffmängd inom gymnasieskolans biologiämne är det en nyckeluppgift för läraren att prioritera undervisningsinnehåll för att ge utrymme/möjlighet till fördjupning och progression. Styrdokumenten anger att eleverna förutom ämneskunskap av faktakaraktär även ska tillägna sig kunskap om "naturvetenskapens karaktär", Nature of science (NOS). Syftet med mitt examensarbete är att utifrån skolans praktik belysa och diskutera förutsättningarna för att använda NOS som innehållsbärande idé där NOS-aspekter utgör ett instrument (bland flera) för stoffurval. Kvalitativa intervjuer har genomförts med fem gymnasielärare i biologi rörande deras uppfattningar om och värderingar av NOS i undervisningen samt om hur de ställer sig till NOS som innehållsbärande idé. Aktuella styrdokument har analyserats med avseende på skrivningar om NOS utifrån vedertagna NOS-aspekter. Genomgången av styrdokumenten har visat att de innehåller talrika skrivningar med koppling till NOS. I intervjuerna uppgav lärarna dock att explicit NOS-undervisning förekom endast i mycket begränsad omfattning. Möjliga underliggande faktorer som kan utgöra hinder för NOS i undervisning träder fram i lärarnas utsagor, exempelvis: • NOS tillmäts inte uppmärksamhet i nämnvärd omfattning vid tolkning av styrdokumenten. • Organisatoriska och administrativa hinder för att genomföra undervisning på ett alternativt sätt. • Brist på lättillgängligt undervisningsmaterial passande en undervisningsuppläggning med NOS. • Omedvetenhet hos lärarna om vad som är känt om NOS-undervisning. Utifrån resultaten i denna pilotstudie anser jag att det finns argument som talar för att vidare undersöka möjligheten att låta NOS bilda en struktur som likt en röd tråd får löpa genom undervisningsplaneringen. Examensarbetet har mynnat ut i ett diskussionsunderlag för fördjupad ventilering av NOS som möjlig innehållsbärande idé i biologiundervisningen samt i ett exempel på undervisningsplanering enligt denna idé.

Det finns lärare som planerar sin undervisning utan att undersöka hur effektiv den är i att komma till rätta med studenternas missuppfattningar. En lärare som vet vilka missuppfattningar som är vanliga och leder till felaktiga svar tror jag har större möjlighet att utforma undervisningen på ett sätt som får eleverna att göra sig av med sina missuppfattningar och därmed svara rätt. Syftet med detta examensarbete var att undersöka hur gymnasieelever i början av tredje årskursen på det naturvetenskapliga programmet uppfattar biologiska begrepp. Verktyget som användes för att undersöka elevernas begreppsuppfattning var Biology Concept Inventory (BCI). Testet besvarades av 66 svenska gymnasieelever i sista året på det naturvetenskapliga programmet. Resultatet från de svenska eleverna jämfördes med resultatet från 85 gymnasieelever i USA. Resultaten från båda länderna visar att många elever väljer bort alternativ där biologiska processer innehåller slump och hellre väljer alternativ som innebär att den biologiska processen styrs av en drivkraft som till exempel det naturliga urvalet eller en koncentrationsgradient. Användningsområden och begränsningar hos BCI diskuteras. Förslag ges till förändrad undervisning och vidare forskning. There are teachers who plan their teaching without examining its effectiveness in overcoming students’ misconceptions. I think that a teacher who knows what misconceptions are common and lead to wrong answers has a better chance to develop their teaching in a way that will allow students to get rid of their misconceptions and hence choose correct answers. The purpose of the present study was to examine concept understanding in biology of Swedish high school students at the beginning of the final year of the science program. The tool used to explore students’ concept understanding was the Biology Concept Inventory (BCI). The test was answered by 66 Swedish high school students in the final year of the science program. The results from the Swedish students were compared to the results from 85 high school students in the United States. The results from both countries show that many students avoid alternatives in which a biological process include randomness and prefer to choose alternatives which means that the biological process is controlled by a driving force, for instance natural selection or a concentration gradient. Applications and limitations of the BCI are discussed. Suggestions for changes in education and further research are given.

Syftet med undersökningen var att kartlägga vilka faktorer som påverkar elever att bli intresserade av biologi. 50 studenter som läser biologi- eller molekylärbiologi¬programmet deltog i en enkätundersökning där de fick svara på öppna såväl som styrda frågor om vilka faktorer, inom och utanför skola, som format deras intresse. Från undersökningen framgick det att studenterna blivit mycket påverkade av sin omgivande miljö under uppväxten och att läraren har en mycket central roll för att skapa positiv attityd för biologi. Resultatet från enkätundersökningen visar att de studenter som genomfört fler laborationer och diskuterat mer också känner att skolan påverkat dem positivt. Studenterna var positiva till att läsa mer om aktuella ämnen.

Med den här uppsatsen har jag velat diskutera relationen mellan utomhusdidaktik respektive inomhusdidaktik som utgångspunkt för undervisningen i den svenska skolan. Ett annat syfte är att med utgångspunkt i ovan nämnda didaktiker fördjupa kunskaperna i utbildningsmetodik för lärare i allmänhet och biologilärare i synnerhet. Studien utgår från två frågeställningar som jag genom intervjuer med två representanter för utomhusdidaktik och två representanter för inomhusdidaktik har försökt besvara. Resultatet av denna studie visar att utomhusdidaktik och inomhusdidaktik kan vara mycket lika i sina fokus på de didaktiska frågorna. Ett undantag är var-frågan som är av större betydelse för utomhusdidaktiken. Studien visar även att utomhusdidaktik berör många fler ämnen än biologiämnet. En viktig slutsats är att undervisningen i skolan ofta saknar verklighetsförankring. Utomhusdidaktik och science-center-didaktik, som representerar inomhudidaktik i denna studie kan båda hjälpa skolan att konkretisera den ofta teoretiska undervisningen och bidra till en ökad förståelse hos eleverna.

Genes are the foundation of evolution and biodiversity. The genetic structure of natural populations needs to be understood to maintain exploited resources rationally. This thesis focuses on genetic variability and methods to determine spatial and temporal genetic heterogeneities. Intense human exploitation generates particular challenges to conserve genetic diversity of fishes since it has genetic effects. My research concerns one of our most valuable fish species: the Atlantic herring (Clupea harengus). I analyzed Atlantic herring samples from the North and Baltic Seas. The objectives were to determine: 1) spatial genetic structure, 2) whether allozymes and microsatellites provide similar descriptions of the differentiation pattern, or 3) if they are influenced by selection, 4) factors affecting statistical power when testing for genetic differentiation, and 5) the temporal stability of the genetic structure. The results show: 1) very low levels of spatial genetic differentiation in Atlantic herring; a major component is a difference between the Baltic and North Seas, 2) a concordant pattern with allozymes and microsatellites, 3) that selection influences a microsatellite locus, which can be a low salinity adaptation, 4) that statistical power is substantial for frequently used sample sizes and markers; the difference in power between organelle and nuclear loci is partly dependent on the populations’ stage of divergence, and 5) no changes in amount of genetic variation or spatial genetic structure over a 24-year period; the selection pattern in one microsatellite locus remained. The notion that the large population sizes make herring unlikely to lose genetic diversity may be disputed. I found small local effective population sizes, and the evidence of selection hints of a distinct evolutionary lineage in the Baltic. When Atlantic herring is managed as very large units, there can be detrimental genetic effects if certain population segments are excessively harvested.

The first objective of this thesis was to investigate effects of endocrine disruptors on the developing brain and gonads of bird embryos. The substances studied were the insecticide methoxychlor, and nine UV-filters (3-benzylidene camphor (3BC), 4 methyl benzylidene camphor (4MBC), benzophenone (BP) 1,2 and 3, 4 hydroxy benzophenone (4 HB), 4 dihydroxy benzophenone (4DHB), benzyl salicylate (BS), and ethyl-4-aminobenzoate Et-PABA)), commonly used in cosmetic products. Some of these substances have no estrogenic effect in vitro, but have been shown to be estrogenic in vivo. The PCB-mixture Clophen A50 is a well-known inducer of biotransformation enzymes and was co-administered with methoxychlor and the UV-filters 3BC and 4MBC. Exposure to 3BC or 4MBC caused ovotestis formation and malformations of the Müllerian ducts in Japanese quail embryos. Co-exposure to one of these compounds and Clophen A50 enhanced the effects, indicating that Clophen A50 potentiates the effects of the UV-filters. Embryonic co-exposure to Clophen A50 and methoxychlor caused a disturbed male sexual behaviour. The metabolites of methoxychlor are estrogen receptor (ER)α-selective, which indicates that the effects on behaviour following embryonic treatment were mediated by ERα. Another objective in this thesis was to localize estrogen receptors (ERs) in the brain of adult and embryonic Japanese quail. The ER localization provides a basis for mechanistic studies on effects of endocrine disruptors, by the identification of estrogen-responsive areas in the brain. We found that ERβ, not previously implicated in sex-differentiation of the brain, was the only ER-subtype present in a sexually dimorphic brain area during differentiation. In conclusion, the estrogenic effects of 3BC, 4MBC and methoxychlor were increased by co-exposure to PCB. These results raise concern since many wildlife species, as well as humans, carry large body burdens of persistent organic pollutants like PCBs, which potentially can interact and enhance the effects of other endocrine disruptors.

Plant-animal interactions are affected by both abundance and distribution of interacting species and the community context in which they occur. However, the relative importance of these factors is poorly known. I examined the effects of predator host range, environmental factors, host plant populations, plant traits and fruit abortion on the intensity of pre-dispersal seed predation in 46 host populations of the perennial herb Lathyrus vernus. I recorded damage by beetle pre-dispersal seed predators, mainly Apion opeticum and Bruchus atomarius with different host ranges on L. vernus as well as on two additional host plants. Local seed predator population size was mainly influenced by plant population size, current seed production and beetle population size in the previous year, but was not strongly affected by connectivity. The monophagous seed predator was less abundant and had lower densities than the oligophagous. Both predator species had a strong ability to track fluctuations in seed production; intensity of predation increased with relative increases in seed production. Oligophagous predation on L. vernus increased with the abundance of alternative hosts, but presence of L. vernus did not affect predation on alternative hosts. Abundances and trait preferences differed among three co-occurring seed predators, but were also associated with the abundance of the other species. Overall, seed predation influenced selection on flower number. I found clear indications of seed predator offence but no obvious plant defence. The pattern of fruit abortion was associated with reduced plant fitness since the seed predator had an advanced ability to locate fruits with high probability of retention. Taken together, different factors influencing abundance of the seed predator species, different preferences, and context dependent trait selection are likely to result in complex spatio-temporal variation in overall seed losses and trait selection in the common host plant.

In this study I investigate the sensitiveness of Bishop's goutweed (Aegopodium podagraria L.)to mechanical damages in an experiment with artificial clipping. Based on personalobservations of A. podagraria during several years I hypothesise that i) A. podagraria indifference with other species, for example different species of grass have difficult to recoverfrom mechanical damages ii) in a site with several other species present A. podagraria willhave harder to recover from mechanical damages than in a pure stand iii) as purer a stand withA. podagraria is, the harder other species will have to establish after the removal of aboveground parts of A. podagraria. The main conclusion of this work is that mechanical damagehas a significant effect on the vegetation cover of A. podagraria. The experiment also provethat a high grade of monoculture favours the ability of A. podagraria to recover frommechanical damage. It could however not be proven that high grade of monoculture of A.podagraria puts constraints on the ability of other species to establish on plots where A.podagraria is removed.

The freshwater crayfish, Pacifastacus leniusculus, mounts a strong innate immune response against microbes such as viruses and bacteria. In this thesis, a novel RNA interference (RNAi) method mediated with histone H2A was developed and applied in crayfish hematopoietic tissue cell cultures for gene functional studies. Further, the interactions between host (crayfish) and pathogens (white spot syndrome virus and Aeromonas hydrophila, respectively) were studied using RNAi technology in live animals. An antilipopolysaccharide factor isolated from viral challenged crayfish by suppression subtractive hybridization was shown to interfere with the propagation of white spot syndrome virus both in vivo and in vitro in crayfish, suggesting an important role of this factor in antiviral defense. Besides, RNAi of phenoloxidase, a critical immune effector involved in melanization, revealed that phenoloxidase activity is necessary for crayfish immune defense against a highly pathogenic bacterial infection in crayfish. In addition, RNAi was also employed to study a marker protein gene involved in hemocyte maturation in crayfish. Taken together, these studies may provide more insights into the immune responses against pathogen invasion as well as hemocyte ontogenesis in crustaceans.

Ixodes ricinus is the main vector of Lyme borreliosis and Tick-borne encephalitis in Europe. Repellents provide a practical means of protection against tick bites and can therefore reduce transmission of tick-borne diseases. In laboratory tests, pieces of cloth treated with MyggA Natural® (a commercial insect repellent) or with the essential oils of Corymbia citriodora (30%), Lavandula angustifolia (1 and 30%), Pelargonium graveolens (1 and 30%), Hyptis suaveolens (10%), Salvadora persica, Pistacia atlantica, Juniperus phoenicea (20%) and methyl jasmonate (MJ) (0.5%, 1.0%, 2.0% and 5.0%) showed strong repellent activity against I. ricinus nymphs. In a tick-infested woodland in east-central Sweden, we tested by randomized, standardised methodology the potential anti-tick repellent activity of MyggA Natural® (roll-on), two concentrations of MyggA Natural® spray, RB86 (a commercially available insect repellent for horses), the essential oil of C. citriodora and three concentrations of MJ. Each substance was dissolved in acetone and applied separately to 1 m2 cloths which were then pulled over vegetation. Nymphal tick numbers on the cloths were recorded at 10-m intervals and differed significantly between treated cloths and the untreated control and also between collectors. Volatile compounds from fresh and dried leaves of H. suaveolens and the essential oils of H. suaveolens (from Laos and Guinea Bissau) and S. persica, P. atlantica and J. phoenicea (from Libya) were collected by solid phase micro-extraction (SPME) and the constituents were identified by gas chromatography - mass spectrometry (GC-MS). Two main sesquiterpene hydrocarbons in the H. suaveolens oil were β-caryophyllene and humulene. These were modified by oxidation and sulphidation to obtain effective tick repellent compounds with lower volatility. In all three oils from Libyan plants the main monoterpene hydrocarbons were α-pinene, sabinene, β-pinene, myrcene, α-phellandrene, 4-carene, β-phellandrene and γ-terpinene. The selected plant species contained numerous volatiles known to have insecticidal, acaricidal, and/or insect repellent properties.

Two distinct stress coping strategies, proactive and reactive, have been stated in various animal studies, each associated with a set of behavioural and physiological characteristics. In a given challenging situation, proactive animals show more aggression, a higher general activity and a predominant sympathetic reaction. In contrast, the reactive copers respond more with immobility and avoidance, and a predominant parasympathetic/hypothalamic activation. This divergence in coping has also been indicated in salmonid fish. Interestingly, many of the differences reported between sea-ranched and wild fish resembles characteristics that differentiate proactive and reactive copers. In the present thesis it is shown that individuals with divergent stress coping styles are identifiable in several brown trout (Salmo trutta) populations. Further, the results show that the distribution of individuals displaying these distinct stress coping strategies differs between populations. This strongly indicates that these traits are heritable and that the variation in selection regime in the native rivers influences these traits. In addition, the results show that populations with hatchery origin are biased towards having higher frequencies of trout displaying a proactive style than populations having wild origin. Also, even though the frequency of early sexual maturation, known as a viable alternative life history in salmonids, differs between populations of brown trout, no link between stress coping strategy and early sexual maturation were found. However, this thesis show that maternal contribution, in the form of egg size, is of major importance whether the progeny will sexually mature early and that it also might be of importance for stress coping strategy. Further, correlations of traits commonly associated with stress coping strategies and behavioural syndromes across context and over time is investigated. The results show that individuals with a strong sympathetic reactivity are more prone to change their behaviour than others.

A low-loaded constructed wetland was investigated with respect to phosphorus retention. Since the main long-term phosphorus retention mechanism is sedimentation and sediment accretion, the study focused on these processes. The purpose of the study was 1) to investigate how the calculated value of phosphorus retention (Pin – Pout), corresponded with the measured amount of phosphorus in the sediment, 2) to find out where in the wetland the phosphorus had accumulated, and in what form it was retained, and 3) to investigate the role of vegetation. The calculated value was 12 kg ha-1 and the measured value was 104 kg ha-1, which indicated the importance of internal phosphorus circulation, where plants probably take phosphorus from the underlying clay. Hence, vegetation could possibly increase the total phosphorus content in the wetland. The composition of phosphorus in the sediment was analysed using sequential fractionation. The dominating form of phosphorus in the sediment was iron-bound phosphorus (29 %). In total, 48 % of the phosphorus was stable, i.e. tightly bound in the sediment, and 35 % was relatively stable. The bioavailable fraction, which could cause eutrophication in downstream waters, was 17 % of the total phosphorus content, or 41 kg ha-1. The amount of total phosphorus was significantly higher near the inlet, compared to the outlet, which is explained by rapid sedimentation of particulate phosphorus entering the wetland. The phosphorus amount near the inlet represented 80 % of the total phosphorus load – which indicates the importance of internal circulation of phosphorus, both biological and geochemical.

Amphibian populations are declining world-wide and one of the suggested reasons is environmental pollutants. Studies of long-term effects on the reproductive system in frogs following larval exposure to environmental pollutants are scarce. It is therefore important to develop methods to study developmental reproductive toxicity in amphibians. In this thesis the usefulness of Xenopus tropicalis (the West African clawed frog) as a model species for a test system was investigated. Effects on the reproductive system after larval exposure to the pharmaceuticals ethynylestradiol (EE2) and clotrimazole were evaluated. The susceptibility to EE2 exposure was compared between the model species and a wild species, the European common frog (Rana temporaria). Larval exposure to EE2 caused female-biased sex ratios in both examined frog species, indicating male-to-female sex-reversal. In adult Xenopus tropicalis, male frogs that were not sex-reversed had reduced fertility and decreased amount of mature spermatozoa in the seminiferous tubules. The proportion of frogs with ovaries but lacking oviducts increased with increasing EE2-concentrations. A female frog without oviducts is sterile. The development of ovaries in sex-reversed male frogs was implied to be similar to control females. The combination of a reduced number of males, due to sex-reversal, and impaired fertility could have severe effects on frog populations. Larval exposure to clotrimazole modulated aromatase activity in gonads and brain in Xenopus tropicalis. Brain aromatase activity was decreased at the time for gonadal differentiation and gonadal aromatase activity was increased at metamorphosis. The findings in this thesis indicate that reproduction in wild frogs might be impaired by estrogenic compounds in the environment. The results combined with the short generation time supports the use of Xenopus tropicalis as a model species when evaluating long term effects of endocrine disruptors on the reproductive system in amphibians.

In nature, environments are often variable and heterogeneous influencing ecological and evolutionary processes. This thesis focus on how animals interact with their environment and how that affects the reproductive decisions they make. Using empirical data collected from wild collared flycatcher populations, experiments and molecular approaches I try to unveil some of these relationships and the evolutionary, ecological and conservation implications of these findings are discussed. Firstly, collared flycatchers were shown to use breeding densities of their own and other species using similar resources when assessing costs and benefits associated to breeding in specific habitats. However, species will vary in how informative they are, and the worst competitor – with whom you overlap most in resources needs – also provides the best source of information. Collared flycatcher parents will also benefit differentially from investments in sons and daughters due to habitat characteristics and dispersal differences between the sexes. Here, I show that they will produce more of the sex that will give the highest expected fitness return given the environment they are in. These results also provide a reciprocal scenario to Clark's (1978) classical study of sex ratio adjustment in relation to local resource competition (LRC), as more of the natal philopatric sex is produced when LRC is low. Secondly, the effect of elaborated ornaments on paternity in the socially monogamous collared flycatcher was shown to be of more importance in areas where the intensity of intra- and intersexual conflicts are expected to be elevated. Hence, ornamentation by environmental interactions determines paternity, illustrating that sexual selection through extra-pair paternity is context dependent. Finally, even though the collared flycatcher populations that this thesis is based on have been studied on their breeding grounds for more then 25 years, we know little of where they are when they are not breeding. Here, stable isotope signatures in winter-grown feathers suggests that they may spend their winter with their breeding ground neighbours and do so repeatedly over years. Differences between breeding populations at this small scale should have many impactions for evolutionary and ecological processes as it will, for example, determine with whom individuals interact throughout their life.

Several plant defense systems consist of enzymes that act on glucosides and produce a toxic compound. In the intact plant tissue the substrate and enzyme are kept apart. The system studied here consists of the substrate 2-O-β-D-glucopyranosyl-4-dihydroxy-1,4-benzoxazin-3-one and the enzyme glucan 1,3-β-glucosidase in rye. The aim was to determine the properties of a cell wall β-glucosidase. Two different systems for expression and purification of β-glucosidase fused to a tag were used: a 6xHistidine tag system and a thioredoxin tag system. The sequence of the β-glucosidase had previously been determined so now the gene was subcloned into E.coli. A direct PCR on colonies, a test expression, a restriction digestion of plasmids and sequencing was made to analyze the transformation, which all turned out successful. Then the β-glucosidase solubility was determined. Finally a purification of the β-glucosidase from E.coli under native conditions and a pNPG assay was carried out. For the (His)6-tagged protein, the recombinant β-glucosidase tended to end up in the insoluble pelleted fraction which indicated formation of inclusion bodies. The cell wall 1,3-β-glucosidase was soluble with the thioredoxin system, but the percentage of soluble protein fraction was around 5% only of the total protein. In eluates from a nickel-nitrilotriacetic acid column the presence of recombinant protein was confirmed with Western blot, but contaminating bands were also present. Purified elauted fractions did not exhibit detectable β-glucosidase activity. It was not possible to purify active enzyme. From a BLAST search it was clear that the most similar enzymes all had putative glycosylation sites and lack of glycosylation could be a reason for the protein not to fold properly.

Lake Bornsjön is situated 30 km southwest of Stockholm in a rift valley lake and consist three basins outstretched in northwest-southeast direction. The surface area is 6,7 km2 with a maximum depth of 18,3 meters, a mean depth of 9,8 meters and a retention time of the water of 6,5 years. The drainage area is 42 km2 and consists mainly of arable land (ca 1000 ha) and productive forestry land (2500 ha), but in the drainage area there are also restored and fairly newly constructed wetlands. Today the Stockholm area receives its drinking water from Lake Mälaren, but if there would be any pollution of this source, Lake Bornsjön would act as the water source. The area surrounding the lake was bought already in 1899 by Stockholm Stad for protection of the lake and was taken over 1993 by Stockholm Vatten AB. It has been a water protection area from 1988 and it was also accepted as a nature reserve in 1995. This involve some restrictions like prohibition against fishing, bathing and to tread the ice on the lake in the winter and only back-up water activities are allowed on and in the lake. According to information from the 1970s the phosphorus content increased in the surface and bottom waters and later in the mid 1980s the phosphorus decreased (Lännergren 1996). 1986 Lake Bornsjön showed some indications of a deteriorated lake status which lead to an investigation the following year that showed an accumulation of phosphorus in the sediment of the deepest parts of the lake (Pettersson 1987). The purpose of the study was to investigate the present leakage of phosphorus from the sediment to the water column in Lake Bornsjön today and to compare the results with the investigation carried out in 1987. The study aims is also to investigate in which basin the leakage of phosphorus is most severe and to try to explain the variation between the basins. Three different methods were used to analyse the content of the phosphorus in the sediment; phosphorus fractionation, ICP-AES and XRF. In a fractionation the phosphorus is determined in six different forms such as NH4Cl-P (loosly sorbed P, porewater-P and in hardwater lakes also CaCO3- associated P), BD-P (P absorbed to iron and manganese and these forms are sensitive for low redox potential), NaOH-rP (P associated mainly with aluminium), NaOH-nrP (organic-P including bacteria-incorporated P), HCl-P (assumed endured apatite) and finally residual phosphorus witch you calculate by taking total phosphorus (TP) minus the extracted forms of phosphorus. The residual phosphorus consist refractory organic P and inert inorganic P. The ICP-AES - method (Inductively Coupled Plasma Atomic Emission Spectroscopy), is used to investigate the amount of elements, in this study phosphorus, iron and aluminium. ICP-AES is a multi element technique and the method can be used to determine around 40 different elements. In the XRF - method (X-ray-fluorescence) the sample is irritated by X-ray beams which results in electron excitation and when the electron falls back in to their original shells it establish fluorescence radiation (Hulterström 2006). The radiation energy is registered by a half detector and dependence on from which shell that the electron falls from it create different kinds of energy and this makes it measurable. With a pulse counter the different energies and elements are separated. The XRF- technique is more sensitive in detecting heavier element. Field work was carried out from a boat using a gravity corer to collect lake sediment cores. In total 18 sediment cores was sampled which were taken at three different occasions in the fall 2006. The sediment sampling was carried out at the same time as the ordinary water samples were collected. The study also included a phosphorus leakage experiment in vitro where sediment cores with the water column above were incubated in 22 days. The results of the investigation show that there is highest share accumulated total phosphorus, deeper than 10 m, with an assumed sediment density of 1 000 000 g/m3 (personal communication Rydin Emil) in the Skårby Basin (BS) 14,90 g/m2 but the highest amount of mobile phosphorus was found in the Bornsjö Basin (BB) 7,08 g/m2 based on data from sediment layer 0-17 cm. The average of total phosphorus in the sediment for the whole lake deeper than 10 m was at the current sampling occasion (2006-10-17) 12,08 g/m2 and mobile phosphorus, 6,54 g/m2. These results are presumably an affect of the artificially induced oxygen in the bottom water by the hypolimnion unit. The hypolimnion unit is placed in the Bornsjö Basin (BB) on 14 m water deep and through aeration of the bottom water the phosphorus accumulates in the sediment. The oxygen that is brought down to the bottom of the lake forms an aerobic environment near the sediment surface which prevents phosphorus leakage (internal loading). Because of a high amount phosphorus in the sediment of Lake Bornsjön is bound to ferric iron (Fe3+ or Fe(III)) in aerobic condition, there is a big threat that this phosphorus will be released when Fe(III) will be reduced to Fe(II) and there is a large risk that it will react with SO42 under anaerobic conditions. The water depth and the location in the lake plays an important role of the amount accumulated phosphorus which is statistically shown in the study. The hypolimnion unit was initiated in 1987 and has since then been active every year between June - October except 2004. Under 2004 a pumping project took place in the Edeby Basin. During this project the bottom water was pumped out of the lake and the result in this rapport show some indications that this project was successful to reduce phosphorus content in Lake Bornsjön. The phosphorus amount in the water during 2006 May-October was 17,27 μg P/L and by this value the lake is a mesotrophic lake. The results from the comparison between different methods to analyse phosphorus show that the methods give quite similar results but the fractionation method is the most informative method about how phosphorus is connected to other substances and consequently the most adequate method to use to calculate the mobile amount of phosphorus. It can be concluded that the phosphorus in Lake Bornsjön mainly derive from the internal loading of the lake, but also from the diffuse inflow from the arable land surrounding the lake and from the densely populated parts in the drainage area. The hypolimnion unit that artificially induces oxygen in the bottom water and makes the phosphorus accumulate in the sediment is positive because phosphorus stays in the lake and is not transported to other lakes or the Baltic Sea. Bornsjön ligger till största delen i Salems kommun, 3 mil sydväst om Stockholm. Sjön är en sprickdalssjö och består av tre bassänger utsträckta i nordväst-sydostlig riktning. Bornsjöns yta är 6,7 km2 med ett maxdjup på 18,3 m och ett medeldjup på 9,8 m och omsättningstiden för vattnet är 6,5 år. Nederbördsområdets area är 42 km2 och består till stor del av jordbruksmark (ca 1000 ha) och produktiv skogsbruksmark (2500 ha) och inom området finns även återställda och nyanlagda våtmarker. Bornsjön är Stockholms viktigaste reservvattentäkt. Sjön och området runtomkring köptes upp för att skyddas redan 1899 av Stockholms stad, övertogs 1993 av Stockholm Vatten AB. Området kring sjön är sedan 1988 ett vattenskyddsområde, dessa bestämmelser reviderades år 2006 och dessutom godkändes det som naturreservat år 1995. Detta innebär vissa restriktioner såsom förbud att bada, fiska, beträda sjön vintertid och endast vattenvårdsverksamhet får förekomma i och på sjön. Uppgifter från 1970-talet visade att fosforhalterna i yt- och bottenvattnet ökade för att sedan minska i mitten på 1980-talet (Lännergren 1996). 1986 visade Bornsjön indikationer på försämrad sjöstatus vilket ledde till en undersökning år 1987 vilket visade en ackumulation av fosfor i sedimentet i sjöns djuphålor (Pettersson 1987). Syftet med denna studie är att utreda den fosforfrigörelse som sker från sedimenten i Bornsjön idag samt att jämföra resultaten med den undersökning som genomfördes 1987. Utredningen har för avsikt att kartlägga var i Bornsjöns tre olika bassänger det läcker mest fosfor från sedimentet till bottenvattnet och förklara varför frigörelsen eventuellt varierar i sjöns olika delar. I studien används tre olika typer av metoder för att fastställa fosformängden, vilket gör att en jämförelse mellan dessa metoder är möjlig. Sammanlagt provtogs 18 sedimentkärnor vid tre olika tillfällen. Sedimentprovtagningen gjordes i anslutning till ordinarie vattenprovtagningar vilket innebär att vattenanalysernas resultat var tillgängliga. Även ett fosforfrigörelseförsök gjordes in vitro där sedimentkärnor med ovanstående vattenpelare inkuberades i 22 dagar. Resultatet av studiens olika delar visar att det finns mest ackumulerad totalfosfor, under 10 meters vattendjup, med en antagen sedimentdensitet på 1 000 000 g/m3 (muntlig kommunikation Rydin Emil) i Skårbybassängen (BS), 14,90 g/m2, men att det finns mest mobil fosfor i Bornsjöbassängen (BB), 7,08 g/m2 baserat på data från sedimentlagret 0-17 cm. Genomsnittlig totalfosforhalt i sedimentet för hela sjön under 10 meters vattendjup, var vid provtagningstillfället 12,08 g/m2 samt mobil fosforhalt på 6,54 g/m2. Vad som påverkat detta resultat mest är förmodligen det artificiellt tillförda syret i bottenvattnet som skapats med hjälp av en hypolimnionluftare placerad i Bornsjöbassängen. Genom att syresätta bottenvattnet ackumuleras fosfor i sedimentet. Även vattendjupet och provplatsen i sjön spelar en viktig roll i sammanhanget vilket bevisas statistiskt i studien. Fosformängden i vattenmassan under år 2006 maj-oktober var 17,27 μg P/L. Vad gäller metodjämförelsen kan konstateras att resultaten följer varandra relativt väl men att fosforfraktionering är den mest informativa metoden då det gäller utredning av fosfor i förhållande till andra ämnen, såsom t.ex. järn, aluminium, kalcium och organiska ämnen. Som slutsats kan konstateras att fosforn i Bornsjön härrör mestadels från internbelastningen i sjön och de diffusa utsläppen som sker då tillflödena till sjön rinner genom näringsrik jordbruksmark men även från de mer tätbebyggda delarna av området.

Biological diversity is one out of four dimensions, characterizing the subject of Biology ac-cording to the school curriculum. As a concept, biological diversity had its break through at the UN environmental conference in Rio de Janeiro in 1992, where the convention about bio-logical diversity, named CBD, was signed. According to the convention, almost all the na-tions of the world have engaged themselves to preserve the national diversity of species, in-cluding the diversity of genetics and ecological systems. This thesis focuses the biological diversity from the perspective of school books. The aim is to find out how the biological diversity is presented in biology books for students aged 12-15 years. In 1994, the current Swedish secondary and high school curriculum called LPO-94 was pre-sented. The biology books used in this study were published between 1994 and 2007, all of them exist in many editions and are published by three different publishers. The conclusion of the study is that all the biology books that were examined have reached different levels of the development in the field of biological diversity.

Human existence and welfare depend on functional ecosystems. Ecosystems are critical to sustain life-support services for human well-being. One method that visualizes that humanity requires ecosystem services for resource consumption and assimilation of produced waste is ecological footprints. This study focuses on the ecosystem service carbon sequestering. A quantification of this ecosystem service showed the potential for accumulation of carbon in different ecosystems in Stockholm and Norrbotten County for the years of 1995 and 2004. This study also provides an estimate of the ecosystem area that is appropriated to accumulate all carbon from total carbon dioxide emissions in Stockholm and Norrbotten County respectively. The appropriated ecosystem area represents the ecological footprint. The ecological footprint is also calculated for Stockholms läns landsting`s total carbon dioxide emissions in 2004. The total potential for accumulation of carbon is lower in the ecosystems in Stockholm County in 2004 than in 1995 and the corresponding figure for Norrbotten County has increased. The results indicate that the total potential for carbon accumulation in Stockholm County was approximately 427 kton C year-1 in 1995 and 352 kton C year -1 in 2004. In 1995 the ecosystems in Stockholm County could assimilate 26% of the county’s total emissions whereas the figure for 2004 was 21%. In Norrbotten County, the total potential for accumulation was approximately 2 824 kton C year -1 in 1995 and 2 983 kton C year -1 in 2004. The ecosystem area that is appropriated to assimilate total emissions of carbon dioxide was smaller in 2004 than in 1995 in Stockholm County and larger in Norrbotten County. The ecological footprint for total carbon dioxide emissions in Stockholm County was 12 696 km2 in 1995 and 12 506 km2 in 2004. The corresponding estimate for Norrbotten County indicate that the ecological footprint for total carbon sequestering was 14 457 km2 in 1995 and 32 146 km2 in 2004. The result shows that both regions require large areas of ecosystem to absorb total emissions of carbon dioxide. Stockholms läns landsting´s ecological footprint was 409 km2, which corresponds to 3.3 % of the County’s total ecological footprint. Stockholm County depends on ecosystem areas outside the region for assimilation of the region’s total emissions of carbon dioxide. According to the results Norrbotten County is self-sufficient with regard to the ecosystem service carbon accumulation. This study also includes a discussion of the advantages and limitations of the ecological footprint as a methodology. The received results serve as the starting point for this discussion. Ecological footprints are pedagogic and communicative indicators and can therefore reach out to a broad audience which is a great advantage with the method. It is a static measure and is therefore incapable of giving any presages. Ecological footprints do not take the dynamics and complexity of ecosystems into account and can therefore not provide any information about the possibilities for ecosystems to deliver ecosystem services at the same quality and quantity in the future. The method does not take socio-economic factors into consideration. For these reasons, ecological footprint should not be used as an indicator for sustainability. On the other hand, ecological footprint can illustrate why an ecologically sustainable development is necessary by visualizing that human welfare and existence rely on functional ecosystems.

Since plants can not escape their predators by walking, they use some other defense systems, like induction or repression of defense genes. A microarray experiment performed with barley attacked by the bird cherry-oat aphid (Rhopalosiphum padi), led to the hypothesis that contig 16360 (similar to ser/thr kinases) could be linked with the resistance of barley against R. padi, and contig 6519 (similar to WIR 1A) with the susceptibility. Time course experiments showed that contig16360 and AJ250283 (similar to BCI-4) are almost induced in the same way, each, by two different aphids (R. padi and Metopolophium dirhodum). Genomic PCR was used to test the hypothesis that when plants have the gene for contig 16360, they are more likely to be resistant against aphid attack, and when plants have the gene for contig 6519, they are more likely to be susceptible. This test was performed with 69 barley lines: wild, commercial or breeding lines. Results were that the presence of WIR 1A gene has no correlation with the susceptibility, while presence of ser/thr kinase seems to be correlated with resistance.

Pseudevernia furfuracea is a shrubby lichen commonly found around the Baltic Sea. The lichen appears to reproduce mainly by producing isidia, propagules of the lichen cortex. It is very morphologically and chemically diverse and can be found on different substrates, such as nutrient poor bark trees and rocks. The main objective of this study was to describe genetic variation in the ITS region and link this to variations in morphology, substrate ecology and secondary chemistry. In total, 36 specimens of P. furfuracea were collected from 21 sites in Sweden, Finland and Estonia. Seven haplotypes were distinguished in the ITS region. A statistically significant connection between haplotype and colouration of the lichen was found. Lighter coloured specimens of P. furfuracea are more likely to be of the ancestral haplotype. No other significant correlations between the different characteristics studied were found, suggesting that P. furfuracea should be regarded as a single species within the Baltic Sea area. This is also supported by the haplotype network.

Landscape effects on species performance currently receives much attention. Habitat loss and fragmentation are considered major threats to species diversity. Deciduous forests in southern Sweden are previous wooded pastures that have become species-rich communities appearing as islands in agricultural landscapes, varying in species composition. Actaea spicata is a long-lived plant occurring in these forests. In 150 populations in a 10-km2 area, I studied pre-dispersal seed predation, seed dispersal and pollination. I investigated spatio-temporal dynamics of a tritrophic system including Actaea, a specialist seed predator, Eupithecia immundata, and its parasitoids. In addition, effects of biotic context on rodent fruit dispersal and effects of flowering time and flower number on seed set, seed predation and parasitization were studied. Insect incidences of both trophic levels were related to resource population size and small Eupithecia populations were maintained by the rescue effect. There was a unimodal relationship between seed predation and plant population size. Seed predator populations frequently went extinct in small plant populations, resulting in low average seed predation. Parasitoids were present in large plant populations but did not affect seed predator density. Seed predators aggregated at edges, relaxing seed predation in patch interiors. Flowering phenology was unrelated to seed set and insect incidence. A higher flower number did not influence seed predation but was associated with higher seed set and a tendency for a higher parasitization rate. In the study on fruit dispersal more fruits were removed inside than outside populations. Within plant populations more fruits were removed from large aggregations. Overall, this thesis underlines the importance of plant-animal interactions during different phases of the life cycle. The spatial configuration of host plants plays an important role for the outcome of plant-animal interactions and trophic cascades.

This thesis concerns different aspects of dating divergence times in phylogenetic trees, using molecular data and multiple fossil age constraints. Datings of phylogenetically basal eudicots, monocots and modern birds (Neoaves) are presented. Large phylograms and multiple fossil constraints were used in all these studies. Eudicots and monocots are suggested to be part of a rapid divergence of angiosperms in the Early Cretaceous, with most families present at the Cretaceous/Tertiary boundary. Stem lineages of Neoaves were present in the Late Cretaceous, but the main divergence of extant families took place around the Cre-taceous/Tertiary boundary. A novel method and computer software for dating large phylogenetic trees, PATHd8, is presented. PATHd8 is a nonparametric smoothing method that smoothes one pair of sister groups at a time, by taking the mean of the added branch lengths from a terminal taxon to a node. Because of the local smoothing, the algorithm is simple, hence providing stable and very fast analyses, allowing for thousands of taxa and an arbitrary number of age constraints. The importance of fossil constraints and their placement are discussed, and concluded to be the most important factor for obtaining reasonable age estimates. Different dating methods are compared, and it is concluded that differences in age estimates are obtained from penalized likelihood, PATHd8, and the Bayesian autocorrelation method implemented in the multidivtime program. In the Bayesian method, prior assumptions about evolutionary rate at the root, rate variance and the level of rate smoothing between internal edges, are suggested to influence the results.

The distribution of plant species and functional traits in alpine and arctic environments are determined by abiotic conditions, but also by biotic interactions. In this thesis, I investigate interactions among plants and herbivory effects on plant community composition and plant functional traits in three different regions: Swedish Lapland, Beringia (USA/Russia) and Finnmark (Norway). Reindeer grazing was found to be extensive in southern Lapland and had limited effects on plant community composition and seedling germination. However, reindeer presence was found to influence plant functional traits, particularly in the subalpine birch forest. Tall herbs were lower and had lower SLA when reindeer were present, while small herbs showed an opposite pattern. The contrasting effects on the two herb groups are probably explained by a competitive release for small herbs when the tall herbs are suppressed by reindeer. Rodents had the largest relative impact on plant community composition in southern Lapland and this is consistent with the study from Finnmark, where rodents heavily affected dwarf shrubs on predator-free islands. With no predators present, vole densities increased profoundly and almost depleted some dwarf shrub species. These results support the idea that small mammals in arctic and alpine tundra are controlled by predators (i.e. top-down). However, a decrease in the nutritional quality in a sedge after defoliation gives support for the idea that small mammals are regulated by plant quality (i.e. bottom-up). In Beringia, small and large herbivores differed in the relation to plant community composition, since large herbivores were related to species richness and small herbivores were related to plant abundance. Plant functional traits were related only to large herbivores and standing crop of vascular plants.

In this thesis, I examine variation in occurrence and performance of glabrous and trichome-producing plants of the perennial herb Arabidopsis lyrata. I combine field studies and genetic analysis to (1) examine the function of trichomes as a resistance character in natural populations, (2) compare the magnitude of population differentiation in trichome-production and at putatively neutral marker loci, (3) examine the molecular genetic basis of trichome-production, and (4) quantify the effects of herbivore removal on population growth and relative performance of glabrous and trichome-producing plants. In a survey of 30 populations of A. lyrata in Norway and Sweden, I documented spatiotemporal variation in damage from insect herbivores. With few exceptions, glabrous plants were more damaged by herbivorous insects than trichome-producing plants in polymorphic populations. Damage levels varied substantially among populations and among years. The intensity of herbivory quantified as mean leaf removal to glabrous plants was higher in polymorphic populations than in monomorphic glabrous populations. Within the Swedish range, populations were more strongly differentiated at the locus coding for glabrousness than at eight putatively neutral isozyme loci. This is consistent with the hypothesis that trichome production is subject to divergent selection. A study of the genetic basis of trichome production showed that glabrousness was associated with mutations in an orthologue to GLABROUS1, a regulatory gene known to cause glabrousness in A. thaliana. Comparative data indicate that the genetic basis of glabrousness varies among populations. Experimental removal of insect herbivores in a natural A. lyrata population increased population growth rate and the relative fitness of the glabrous morph. The results suggest that insect herbivory may influence both population dynamics and selection on trichome production in A. lyrata.

Speciation is the process describing the formation of new species and is at the heart of evolutionary biology. According to the biological species concept only reproductively isolated forms are regarded good species. This thesis aims at identifying evolutionary processes that cause population divergence and, ultimately, speciation. Natural and sexual selection are two major candidates driving changes in traits that could render populations reproductively incompatible. In recent years, biologists have recognized that most animal species are polygamous. Therefore, sexual selection does not end at mating but continues to include interactions between individuals after mating has occurred but before zygote formation. Male-male sperm competition and cryptic female choice are two main forms of postmating sexual selection shaping reproductive traits like behaviour. The studies presented in this thesis focus on laboratory experiments attempting to identify the role of postmating sexual selection in causing reproductive divergence across populations in beetles. The majority of studies were performed using a Bruchid beetle, Callosobruchus maculatus, a common, worldwide pest on stored leguminose seeds. I used two major methodological approaches. One approach seeks to identify the traces left by past selection among extant conspecific populations, by assessing the pattern of female reproductive responses to mating with males of decreasing relatedness. Second, I used a selection experiment to disentangle the joint effect of natural and sexual selection acting simultaneously on diverging replicated selection lines. In general, these experiments revealed that postmating sexual selection can be a powerful engine of incipient divergence between allopatric populations. Changes in traits underlying variables such as female reproductive output, female mating rate or male success in sperm competition evolved rapidly and could in some cases effectively reduce gene flow between conspecific populations. While postmating sexual selection per se can drive divergence, I found that interactions with natural selection can limit divergence in reproductive characters. Sexual selection tended to reinforce natural selection under strong directional selection. In contrast, sexual selection inflicted a reproductive load on populations under weak natural selection. Thus, the joint effects of natural and sexual selection on allopatric populations are non-trivial and should be considered in greater detail in future studies of early divergence.

The genetic information required for the existence of a living cell of any kind is encoded in the sequence information scripted in the double helix DNA. A modern trend in biology struggles to come to grip with the amazing fact that there are so many different cell types in our body and that they are directed from the same genomic blueprint. It is clear, that the key to this feature is provided by epigenetic information that dictates how, where and when genes should be expressed. Epigenetic states “dress up” the genome by packaging it in chromatin conformations that differentially regulate accessibility for key nuclear factors and in coordination with differential localizations within the nucleus will dictate the ultimate task, expression. In the imprinted Igf2/H19 domain, this feature is determined by the interaction between the chromatin insulator protein CTCF and the unmethylated H19 imprinting control region. Here I show that CTCF interacts with many sites genome-wide and that these sites are generally protected from DNA methylation, suggesting that CTCF function has been recruited to manifest novel imprinted states during mammalian development. This thesis also describes the discovery of an epigenetically regulated network of intra and interchromosomal complexes, identified by the invented 4C method. Importantly, the disruption of CTCF binding sites at the H19 imprinting control region not only disconnects this network, but also leads to significant changes in expression patterns in the interacting partners. Interestingly, CTCF plays an important role in the regulation of the replication timing not only of the Igf2 gene, but also of all other sequences binding this factor potentially by a cell cycle-specific relocation of CTCF-DNA complexes to subnuclear compartments. Finally, I show that epigenetic marks signifying active or inactive states can be gained and lost, respectively, upon exposure to stress. As many genes belonging to the apoptotic pathway are upregulated we propose that stress-induced epigenetic lesions represent a surveillance system marking the affected cells for death to the benefit of the individual. This important observation opens our minds to the view of new intrinsic mechanisms that the cell has in order to maintain proper gene expression, and in the case of misleads there are several check points that direct the cell to towards important survival decisions.

This thesis focuses on the interactions among microbiota in clearwater lakes. Field sampling and field experiments were performed to evaluate interactions among microbiota and the importance of benthic versus pelagic microbiota in terms of biomass and production. In addition, carbon cycling in an oligotrophic clearwater lake was calculated. Biomass and production of microbiota was clearly focused to the benthic habitat. During natural nutrient concentrations growth of heterotrophic bacteria (benthic and pelagic) was coupled to production of microphytobenthos in Lake Eckarfjärden, indicating interactions between autotrophic and heterotrophic microbiota in, as well as between, habitats. At increased nutrient concentrations, growth of heterotrophic bacteria was not correlated to microphytobenthos production. This was explained by less release of dissolved organic carbon (DOC) from microphytobenthos when they got access to more nutrients. Further investigations showed different scenarios in oligotrophic clearwater lakes following increased nutrient concentrations. The interactions between microbiota may be altered following increased nutrient concentrations and the microbial mat either positively or negatively affect the pelagic microbiota. The most striking result was that the expected shift towards dominance of pelagic primary production does not necessarily occur. Major flows of carbon were identified between different habitats in the oligotrophic clearwater Lake Eckarfjärden, and the net result was that the benthic habitat provided carbon to the pelagial. High DOC concentrations in the lake together with low pelagic production are factors that would indicate net heterotrophy. Accordingly, the pelagial of Lake Eckarfjärden was net heterotrophic but when the benthic and littoral habitats were included in the calculations, the lake turned out to be net autotrophic. In conclusion, the benthic microbiota contributed significantly to the total production in the investigated lakes and had a major role in the lake metabolism. Thus, this thesis emphasises the importance of benthic microbiota in shallow clearwater lakes.

Fisheries agencies around the Baltic Sea use hydroacoustics to assess stock sizes of herring and sprat. These assessments rely on the assumption that the acoustic properties of Baltic clupeids are the same as North Sea herring. This may lead to biased results, as system-specific differences in salinity and fish fat content may influence acoustic target strength. The acoustic properties of the Baltic clupeids were explored and a new relationship between target strength and fish length was developed (paper I). The intercept of this new relationship is 3.4 dB higher than normally used by the agencies. Applying this new relationship would reduce the acoustic stock biomass estimates by approximately 50%. Diel variation in the vertical distribution of fish may influence acoustic abundance estimates. Fish body posture may influence target strength and if fish concentrate near the surface or bottom this may affect detectability by an echo sounder. A seabed-mounted, upward pinging echo sounder was used to study diel variation in vertical distribution, acoustic size distribution and abundance of fish (Paper II). Differences between day and night were substantial and it was concluded that night time acoustics are to be preferred, at least in our study area. The seabed-mounted echo sounder was also used to study fish swimming activity and vertical distribution in relation to light intensity and water temperature (paper III). Four phases of fish distribution were distinguished over the diel cycle (day, night, dawn and dusk). Acoustic tracking was used to estimate the swimming speed of individual fish. The speed varied among the diel periods and the greatest difference was observed between day and night with twice as high swimming speed during the day. Regression models were developed to investigate the effects of fish size and environmental factors (water temperature, light intensity at the sea surface and in situ, measured at the depth of the fish) on swimming speed. Fish size, light intensities and temperature were all significant variables in the models, with fish size being generally most important. These results have clear implications for fish bioenergetics models. Such models should account for seasonal, light-driven cycles in the activity-induced respiration estimates, in particular when modelling populations at high latitudes. Vertical and horizontal fish distributions were studied from spring through autumn during two consecutive years (paper IV). The seasonal dynamics in vertical distribution patterns were consistent between years. Prior to thermocline formation, fish of all sizes concentrated near surface where water temperatures were higher than in the underlying water mass. During the summer period of pronounced thermal stratification, larger fish were found deeper than small individuals (including young-of-the-year fish), which remained close to the surface. In the autumn, when the thermal stratification diminished, the small fish moved somewhat deeper while larger individuals dispersed throughout the water column. Fish showed clear horizontal patchiness, but horizontal distributions were not significantly related to wind directions.

In this thesis the genetic variation of two grouse species, the Chinese grouse (Bonasa sewersowi) and the Black grouse (Tetrao tetrix) was examined with neutral genetic markers: microsatellites. Habitat fragmentation and isolation leads to structuring among and loss of genetic variation within populations. The Chinese grouse in a small population in Lianhuasan nature reserve was found to have undergone a population bottleneck and as a result of isolation and possible inbreeding showed genetic impoverishment hereof. The Black grouse populations in Europe face various different conditions from widely distributed areas of suitable habitat in the northern and eastern parts of its range to highly naturally and anthropogenically fragmented habitat landscapes in the west. Structure among populations was found in Great Britain where Wales, Scotland and England showed characteristics of three different genetic entities, indicating very little or no geneflow between these populations. The Dutch population showed signs of loss of genetic variation as to be expected from a population that has historically decreased in population size from several thousands to tens of individuals in a matter of decades. However the possibility to spot signs of a bottleneck was impaired due to the short time-window in which this can be observed in a population with such a low effective population size (NE). The sampled populations in Europe clustered into five different groups of genetic identities. The different clusters were: Great Britain-, the Netherlands-, Fenno-Scandian-, Alpine- and lowland German-Austrian populations. The level of genetic variation when compared over all these different populations decreased as a sign of isolation and small NE. However it was not feasible to separate the impact of these two factors.