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Na Ljubljanskem Barju v Sloveniji smo opravili dendrokronološke raziskave lesa iz eneolitskega koliščarske naselbine Parte-Iščica. Iz struge reke Iščice smo odvzeli vzorce 1237 kolov iz lesa jesena (Fraxinus sp.), jelše (Alnus glutinosa Gaertn.), bukve (Fagus sylvatica L.), jelke (Abies alba Mill.), javorja (Acer sp.), breze (Betula sp.), leske (Corylus sp.), belega gabra (Carpinus betulus L.), topola (Populus sp.), hrasta (Quercus sp.), vrbe (Salixsp.) in bresta (Ulmus sp.). Prevladovali so vzorci jesena, jelše in bukve s 70 %, 9 % in 7 %. Dendrokronološke analize smo opravili na jesenovih, bukovih, hrastovih in jelovih kolih, ki so imeli nad 45 branik. Na osnovi 285 relativno datiranih vzorcev smo sestavili dve jesenovi in eno bukovo kronologijo, dolžin 136, 113 in 105 let. Večje količine lesa, posekanega v istem koledarskem letu, nakazujejo potek gradbenih aktivnosti na kolišču. Po prvih rezultatih radiokarbonskega datiranja uvrščamo koliščarsko naselbino v prvo polovico tretjega tisočletja pred našim štetjem. From the Parte-I{~ica Eneolithic pile dwelling in the Ljubljana Moor, Slovenia, timber was collected for dendrochronological investigations. In the river bed of the I{~ica river samples were selected from 1237 vertical piles of ash (Fraxinus sp.), alder (Alnus glutinosa Gaertn.), beech (Fagus sylvaticaL.), fir (Abies alba Mill.), maple (Acer sp.), birch (Betula sp.), hazel (Corylus sp.), hornbeam (Carpinus betulus L.), poplar (Populus sp.), oak(Quercus sp.), willow (Salix sp.), and elm (Ulmus sp.). Those of ash, alder, and beech predominated with 70 %, 9 %, and 7 % respectively. Samples ofash, beech, oak, and silver fir containing more than 45 tree-rings were usedfor tree-ring analyses. 285 samples were cross-dated and three floating chronologies, two of ash and one of beech, were constructed. Their length was 136, 113, and 105 years. The large amount of timber cut in the same calendar year provides information on building activities on the site. The first 14C dates indicate that the pile dwelling existed in the first half of the 3rd millennium BC.

Vsebina publikacije na kratko povzema izsledke projekta Go for Mura. Predstavljeni so poplavni in močvirni gozdovi ob Muri, njihov pomen ter različni vidiki omenjenih gozdov, ki so bili raziskani tekom projekta. Predstavljene so ostale aktivnosti projekta .

Predstavljene so osnove dendrokronološkega datiranja in primeri uspešnih, delno uspešnih in neuspešnih datiranj lesenih konstrukcij in stropov v Sloveniji. Dendrokronološka analiza se začne z odvzemom, pripravo in deteminacijo vzorcev. Pri datiranju se srečujemo s številnimi težavami, kot so problematične drevesne vrste, premajhno število branik in nezmožnost odčitavanja branik. Macesnovina, jelovina, smrekovina in hrastovina spadajo med lesne vrste, s katerimi se pri analizah največkrat srečamo. Z datiranjem macesnovine in jelovine skoraj ni težav, veliko pa jih je pri datiranju smrekovine in hrastovine. We present the basics of dendrochronological dating together with examples of successful, less successful, and unsuccessful dating of roof constructions and ceilings in Slovenia. Each analysis starts with coring, sample preparation, and wood determination. It is not always possible to date a sample, because we are faced with many obstacles as problematic growth patterns, unsuitable tree species, too few tree-rings, or sometimes the high value of the analysed object which may not be damaged by sampling. The larch, spruce, silver fir and oak are most frequently investigated. Dating of larch and silver fir is often possible but we face many problem s with the spruce and oak.

V Dinarskem fitogeografskem območju smo na 6 raziskovalnih objektih preučili pojav prirastne depresije pri jelki v obdobju 1960-1995. Vzorčili smo v transektih dolžine 400-600 m. Skupaj smo analizirali 365 jelk različnih stopenj prizadetosti. Ugotovili smo, da se je prirastna depresija začela leta 1960 in da je prirastek upadal do leta 1986, nato pa se je začel povečevati. Povečevanje širine branike in pozitiven odziv jelke na izboljšanje rastnih pogojev sta močno odvisna od rastnosti dreves. Tako so se na izboljšanje najbolj odzvale navidezno neprizadete jelke, medtem ko pri prizadetih jelkah izrazitega izboljšanja ni. Pri močno prizadetih jelkah pa se propadanje nadaljuje. Izkazalo se je, da so najbolj prizadeti tisti objekti, ki ležijo bliže urbanih središč in manj tisti, ki so od njih bolj oddaljeni Six research plots in Dinaric phytogeographic region were chosen to enable the analysis of the growth depression of the silver fir (Abies alba Mill.) from 1960-1995. Sampling was done in 400-600 m long transects. Altogether 365 trees of various health condition were analysed. It was established that growth depression started in year 1960 and reached its lowest point in 1986. Thereafter the increment slowly started to increas. Increment increase and positive reaction of silver fir strongly depend on individual silver fir vitality. The unaffected silver firs have positively reacted with increment incerease, while heavelly affected continue with increment decline showing no improvement at all. Intermediatelly affected silver firs have evidenced only moderate increment recovery. It was also observed that the research objects in the viccinity of urban centers (Ravnik, Javornik and Mokrec) exhibited higher increment decrease than the distant ones (Glažuta, Mašun and Škocjan)

V dinarski fitogeografski regiji smo izbrali 7 raziskovalnih objektov z najmanj 15 drevesi na objekt. V raziskavo so bile vključene samo odrasle vladajoče in sovladajoče jelke ne glede na osutost krošnje. Sušic in umirajočih jelk nismo upoštevali. Na dveh izvrtkih ali enem kolobarju na drevosmo izmerili širine branik. Več zaporedij širin branik smo združili v lokalno kronologijo za objekt. Slovenska dinarska kronologija pokriva obdobje 1790-1995 in vizualno dobro sovpada z nemškimi. Rastni trendi lokalnih kronologij za različno prizadeta drevesa se po letu 1960 obrnejo strmo navzdol. Depresija doseže najnižjo točko leta 1976, nato pa se začne prirastekpovečevati. Obdobje depresije je najmanj prizadelo navidezno zdrave jelke, najbolj pa močno prizadete. V zadnjih 100 letih smo identificirali 20 značilnih let (11 negativnih in 9 pozitivnih). Topli spomladanski meseci in poletni z več padavinami so najbolj ugodni za prirastek jelke. Z odzivnimi funkcijami smo pojasnili od 30 do 60% variabilnosti širin branik, kar pomeni, da metoda ne daje vedno zadovoljivih rezultatov. Z debelno analizo smo identificirali tudi do 11 izpadlih branik, ki smo jih s pomočjo regionalne kronologije postavili v čas. Negativni vpliv gospodarjenja se kaže v stalnem zniževanju lesne zaloge in s tem povezanim upadanjem širine branike. Lesna zaloga pod 450 m3/ha ne zagotavlja več ugodne sestojne klime za jelko. Poseki visoke jakosti povzročijo pri jelki stres, na katerega se odzove z upadom prirastka. Po nekaj letih se, pri ne prehudem posegu, prirastek povrne na nivopred posegom. Delež kasnega lesa z višino debla upada, vendar lahko to zakonitost modificira sekundarna krošnja. Prirastna ritmika odziva juvenilnegain adultnega lesa je primerljiva. Seven geographical locations with at least 15 trees were selected in the Dinaric phytogeographic region. All trees, except dead and clearly dying ones,were analysed. Tree-ring widths were measured on two cores or on one stemdisc. Slovene Dinaric silver fir chronology was built on this basis. It covers the period 1790-1995. Comparison of the Slovene regional chronology with the South German and the Bavarian one revealed moderate visual comparability but not very high statistical values. Growing trends in the local chronologies of differently affected silver firs decline rapidly after the year 1960 and reach their minimum in 1976. Thereafter the radial incrementincreases. Especially weak silver firs were most heavily affected. Inthe last 100 years 11 negative and 9 positive signature years were detected.Warm spring months and moderately warm summer months with above average precipitation are most favourable for the increment. Tree-ring width variability can be explained by response functions in the 30-60% range. This indicates that the method doesnćt always give satisfactory results. In the stem analysis 11 missing rings were dated and identified with the help of the regional chronology. Unappropriate forest management has negative influence onsilver fir increment. A fast reduction of the growing stock below 450 m3/ha can provoke a destruction of selfprotecting mechanisms in the forest site and its mechanical and biological stability is endangered. Silver firs respond to the instability of the forest stand with decrease of increment and reductions of the crown. The amount of latewood decreases acropetally, however this trendcan be modified by secondary crown. The growing rhythm of the juvenile and adult wood is comparable.

The main objective of this study was to investigate tree-ring width before, during and after onset of significant SO2 air pollution around coal-fired power plants Šoštanj (TEŠ) and Trbovlje (TET). The surviving trees showed relative large growth oscillations and the most obvious effect of air pollution caused by coal-fired power plant on tree-ring width (TRW) can be observed in narrower TRW, which is, among other, connected with needle loss in Norway spruce. This is evident on plots closer to TET - reference plot has significantly higher radial increment as heavily and moderately affected plot. Plots around TEŠ show smaller, but still significant difference, between heavily and moderately affected plot and reference. It was also proven, on all affected plots, that the affected trees showed reduced response to favourable climatic conditions compared to healthy trees and more sensitive response to unfavourable climatic conditions. The study of pointer years showed that only some negative pointer years on plots very close to source of pollution could be directly connected to the beginning and gradual increase in power plant production. Coal-fired power plants have significant influence on tree growth. Site productivity is not fully used, trees are under constant stress, they react very sensitively to environmental stresses (such as drought) and recovery is slower compared to healthy trees. By installing filters on coal-fired power plant TEŠ, significant reduction of emissions occur, on the other hand TET approach to solving this problem was by building a 360 m high chimney which, however, did not reduce the emission but rather dispersed them over a larger area. TRW on affected plots around TEŠ gradually increased and is now more or less similar to TRW on a reference plot. TRW around TET show similar trend, although this is not due to significant increase in TRW on affected plot but more to the TRW decrease on a reference plot. Namen študije je bil analizirati širine branik pred obdobjem največjega onesnaževanja z SOo2, med tem obdobjem in po sanacijskih ukrepih, opravljenih na termoelektrarnah Šoštanj (TEŠ) in Trbovlje (TET). Analiza širin branik preživelih dreves na ploskvah bliže TET in TEŠ je pokazala, da so bile branike v obdobju največjega onesnaževanja znatno ožje kot tiste na manj vplivanih lokacijah. Izkazalo se je tudi, da je odziv dreves na klimatske vplive na bolj in manj vplivanih ploskvah sicer primerljiv - vsa drevesa so se odzivala enako, vendar tista bliže termoelektrarnam bolj, tista z bolj oddaljenih ploskev pa manj in so se tudi hitreje vrnila v stanje normalnega priraščanja kot prizadeta drevesa. Primerjava rasti s klimo je pokazala, da je večina pozitivnih in negativnih značilnih let sicer posledica klimatskih dejavnikov, vendar pa lahko nekatera značilna leta na ploskvah bliže virom onesnaževanja nedvoumno pripišemo postopnemu povečevanju proizvodnje v termoelektrarnah in posledičnemu povečevanju emisij SO2 v ozračje. Na osnovi teh ugotovitev sklepamo, da je vpliv termoelektrarn na debelinski prirastek drevja omejujoč. Proizvodna sposobnost rastišč ni izkoriščena, drevesa so v konstantnem stresu, na dodatne okoljske strese se odzivajo občutljiveje kot drevesa zunaj vplivnega območja, normalizacija rasti po nastopu ugodnih rastnih razmer pa je daljša. Po namestitvi odžvepljevalnih čistilnih naprav v TEŠ in postavitvi odvodnika v TET so se razmere za rast dreves v okolici termoelektrarn izboljšale, kar se kaže tudi v postopoma vedno manjših razlikah med rastjo dreves na vplivnih in manj vplivnih območjih. Izboljšanje rasti prizadetih dreves je bolj izrazito v okolici TEŠš, kjer je bila ekološka sanacija učinkovitejša; manj pa se je rast izboljšala v okolici TET, kjer je 360 m visoki odvodnik emisije samo razpršil na večje območje.

Raziskava je del projekta, ki preučuje ogljikov cikel na zaraščajočih kraških pašnikih v submediteranskem območju Slovenije na Podgorskem Krasu (JZ Slovenija). Analize smo opravili na dveh raziskovalnih ploskvah v različnih stadijih zaraščanja z gozdom (pašnik in z drevjem deloma zarasel pašnik). Cilj našega dela je bila ocena biomase lesnatih rastlin na zaraščajoči površini in primerjava s pašnikom. Delali smo v skladu z metodologijo kot jo predlaga Terrestrial Carbon Observation Panel (TCO), ki je del Global Terrestrial Observing System (GTOS) - http://www.fao.org/gtos. Na podlagi natančne inventure lesnatih rastlin smo s pomočjo alometrijskih funkcij izračunali biomaso lesnatih rastlin. Skupna biomasa lesnatih rastlin na zaraščajočem se pašniku je bila ocenjena na 32.065 t ha-1. Glavnina (86%) vse biomase odpade na puhasti hrast (Quercus pubescens L.). Z dendrokronološko študijo smo na vzorcu 18 dreves preučili tudi priraščanje biomase v času in prostoru. Ugotavljamo, da je v 52 letih gozd zasedel kar 21% suhega kraškega pašnika. Analiza volumenskega prirastka je še pokazala, da nobeno od analiziranih dreves še ni doseglo kulminacije volumenskega prirastka in da je to z vidika ponora ogljika zaželeno. Naša spoznanja so pomembna za razumevanjeprostorskih in časovnih sprememb v zalogah ogljika in o pomenu gozda za shranjevanje ogljika in blaženje klimatskih sprememb. Our research was part of a broader study that deals with the carbon cycling in abandoned karstic pastures of Slovenian sub-mediterranean region (Podgorski kras, SV). At this site two study plots that differ in succession (pasture andgrassland invaded by woody plants) are researched. The aim of our work wasto make estimation of woody plants biomass at invaded area. The method for the field measurements of biomass was one proposed by Terrestrial Carbon Observation panel (TCO) of, the Global Terrestrial Observing System programme (GTOS) (http://www.fao.org/gtos/). We did an inventory and we calculate total woody biomass for each species with different allometric equation. Total woody biomass of the site was estimated to 32,065 t , and was mainly contributed by pubescent oak (Quercus pubescens L., 86 % of total). We did also a dendrocronological measurement, we took samples from 14 trees with a increment borer and we also collected disks from 4 trees. In 52 years the forest overgrowth 21% of dry karstic pastures we can see that in ours samples trees, we observe a significant growth in these years analizing our samples trees. None of the trees in our case culminate and biomass production is in all trees in exponential increase that culmination is reached at very high ages so basically carbon storage is constantly increasing. The information on diameter increment and growth patterns of trees contributes to understand the changes in carbon stock during woody plant encroachment.