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Saabunud / Received 11.02.2020 ; Aktsepteeritud / Accepted 08.05.2020 ; Avaldatud veebis / Published online 12.05.2020 ; Vastutav autor / Corresponding author: Jane Raamets e-mail: jane.raamets@taltech.ee Straw and reed are natural local insulation- and construction materials, which properties allow them to replace energy intensive building materials. In general, straw and reed as building materials are considered harmless to the environment and human health. Unfortunately, the use of these materials may bring about mould growth in buildings which may result in different diseases (for example irritation of eyes, nose and throat, allergic rhinitis, conjunctivitis, and asthma) in people with weaker immune systems. No research has been carried out on the topic of microbiological community in straw and reed houses in climatic conditions similar to Estonia, although buildings made of natural materials are becoming more and more popular. The aims of the study were to investigate the indoor climate of buildings with straw and reedbale walls and to determine the factors influencing indoor air quality. In order to fulfil the set aim: (1) air quality was tested in the bedrooms of the studied houses, and the microbial species in air and walls were determined; (2) the indoor air quality parameters (CO2, RH%, and temperature) in air and at two different heights in the walls were measured. The results enable to conclude that the walls of straw or reed-bale house are suitable in Estonian climatic conditions, which as a result of professional design, usage of materials suitable for building, and high-quality craftsmanship provides a healthy and environmentally friendly housing.

Urban brownfields are ecologically valuable ecosystems that have been and are under various anthropogenic influences. Because brownfields are subject to rapid development in urban areas, their biological communities, including soil mesofauna, are overlooked and seldom researched, even though they could provide valuable insight into the ecological functioning of these areas. This exploratory study describes the community characteristics of oribatid mite fauna of 12 brownfields in Tallinn, Estonia, and analyzes the potential of oribatid mites as bioindicators of brownfield successional stage. This study provides the first faunistic list of oribatid mites from the brownfields of Tallinn. No significant changes in species abundance or richness depending on the successional stage were discovered. While some changes in community structure were noted, due to low overall abundance, no clear indicators of brownfield successional stage were identified. For future research on urban brownfield oribatid fauna with the intention of finding potential bioindicators of brownfield properties, increasing the sampling size and inclusion of other groups of soil mesofauna is recommended.

Magistritöö Aianduse õppekaval Muld vastutab nii kliima regulatsiooni, veeringluse, reostuskontrolli ja varude säilitamise eest.Samuti on muld elukeskkonnaks mullafaunale, kes osaleb nii mullas toimuvas aine – ja energiavahetuses kui ka lagunemisprotsessides Käesoleva magistritöö eesmärgiks oli välja selgitada pinnasepüüniste ja mullaproovide abil, kas agrotehnilised võtted omavad mõju mullafauna gruppide esinemisele eri vanuselistes mustikaistandikes. Töö tulemustest selgub, et kõige arvukam on mullafauna vanas, 2003. aastal rajatud mustikaistandikus. Uuel alal (2017. aastal rajatud mustikaistandikus), kus kasutatakse erinevaid agrotehnilisi võtteid (multśimine, kastmissüsteemid) olid arvukusnäitajad pea poole madalamad. Töö tulemustest selgus ka, et mikrovihmutamine omab mõju mullafauna gruppidele. Alal, kus kasutati mikrovihmutamist, puudusid 2018.aasta juunis nälkjad, sarnastiivalised (Homoptera), lehetäilised (Aphidoidea), teod (Gastropoda) ja augustis ka lutikalased (Heteroptera)). Lisaks agrotehniliste võtete kasutamisele tuleb arvesse võtta ka istandike vanust. Vanal alal on kooslus koos eksisteerinud pikemat aega ja seega ka stabiilsem. Kindlamate järelduste tegemiseks on soovitav korrata läbiviidud katseid rohkemate paralleelide arvu ja kontrollalade kaasamisega. Soil is responsible for climate regulation, water circulation, pollution control and stock conservation. Soil is also a living environment for soil fauna, which participates in both soil and energy exchange and degradation processes. The aim of this thesis was to find out, using soil traps and soil samples, whether agrotechnological techniques have an impact on the occurrence of soil fauna groups in blueberry stands of different ages. The results of the work presented that the most abundant is soil fauna in the old blueberry plantation, which was founded in 2003. In the new area (a plantation, which was founded in 2017), were different agrotechnological techniques (mulching, irrigation systems) are used, the abundance was almost half from the abundance of old plantation. The results also presented that micro-sprinkling has an impact on soil fauna groups. In the area where micro-sprinkling was used, in June 2018 there were no species of slugs, snails, homoptera, aphids found. In August there were no animals from genus Heteroptera found. In addition to the use of agrotechnological techniques, the age of plantations must also be taken into consideration. In the old area, the community has co-existed for a long time and thus more stable. In order to draw more firm conclusions, it is advisable to repeat the experiments.

Magistritöö Maastikukaitse- ja hoolduse õppekaval Escherichia coli ja enterokokkide esinemise ja arvukuse alusel hinnatakse veekogudes suplusvee kvaliteeti. Käeolevas magistritöös analüüsitakse Escherichia coli ja enterokokkide sisaldust erinevates veekogudes ning arvukuse sõltuvust erinevatest keskkonnafaktoritest. Andmeanalüüsiks kasutati Terviseametist väljastatud 2012–2017. aasta veekogude mõõtmisandmeid ning nendest lähtuvalt koostati arvandmete analüüs statistikaprogrammis R (R Core Team 2019). Escherichia colid ja enterokokid on statistiliselt usutavalt mõjutatud kõikidest uuritud keskkonnateguritest: kuu, aasta ja veekogu liik ning nendevahelistest koosmõjudest. Kõige madalam Escherichia colide ja enterokokkide keskmine arvukus esines järves ning kõige kõrgem jões. Vähem baktereid leidus aprillikuus võetud proovides. Aprillist kuni septembrini kasvas järk-järgult nii Escherichia colide kui ka enterokokkide arvukus. Enterokokkide ja Escherichia coli bakterite arvukuse vahel esineb keskmine korrelatiivne seos (r=0,47). Aastatel 2012–2017 analüüsitud veeproovides esines kõige rohkem Escherichia coli ja enterokokkide ületamisi Tartu ja Valga maakondades. Mõlema bakteri piirväärtus oli uuritud aastatel enim ületatud Pedeli paisjärves ja Anne kanalis. Paljud keskkonnafaktorid mõjutavad sarnaselt nii Escherichia colide kui ka enterokokkide arvukust. Põhjus peitub ilmselt ka selles, et Escherichia coli ja enterokokkide arvukus on omavahel korrelatiivses seoses. Samas tõstatavad mitmed varasemalt koostatud teadustööde omavahelised vasturääkivused üles küsimusi, mistõttu vajab Escherichia coli ja enterokokkide arvukuse hindamine sõltuvalt erinevatest keskkonnatingimustest senisest spetsiifilisemat lähenemist. The perfomance of Escherichia coli and enterococcus in water reservoirs is used to assess water quality. The Health Board examines specific water bodies in detail and registers the overfulfilment of state-imposed bacterial limits. The pupose of the current study was to assess the quantity of Escherichia coli and enterococcus as potential pathogenic bacterial species in different reservoirs in Estonia and the dependence of abundance from environmental factors. The data of 2012–2017 received from Estonian Health Borad were used to fulfill the purpose of the study. The analyse was performed in R. Results indicate that the abundance of both Escherichia coli and enterococcus is statistically significant from month, year, the type of water body and their interactions. The lowest average value of Escherichia coli and enterococcus was registred in lakes and the highest in rivers. The average concentration of both bacterial species was lowest in April and increased gradually from April to September. Current study proved that there is a positive correlation between the abundance of Escherichia coli and enterococcus in bathing water bodies (r=0,47). In 2012–2017 the highest excesses of Escherichia coli and enterococcus was registred in Tartu and Valga Counties. Pedeli paisjärv and Anne kanal were the most problematic reservoirs concerning bacterial exceedings. The abundance of both Escherichia coli and enterococcus is dependent from similar environmental factors probably since there is a positive correlation between the quantity of Escherichia coli and enterococcus. Nevertheless, controversial results of different academic studies indicate the necessity of more specific approach considering bacterial reproduction dependence from different environmental factors.