Effect of climate on growth of european larch (Larix decidua Mill.) at the upper treeline in the southeastern Alps

Na 7 lokacijah na zgornji gozdni meji v jugovzhodnih Alpah smo preučili odvisnost med širino branike macesna (Larix decidua Mill.) in klimo. Analizo smo napravili za obdobje 1900-2003, v katerem smo ugotovili 13 skupnih pozitivnih in 17 skupnih negativnih značilnih let. Izkazalo se je, da je macesen zelo primerna drevesna vrsta za preučevanje odziva dreves na klimo. Največji vpliv na nastanek široke branike imajo nadpovprečne junijske temperature, najbolj negativen vpliv na širino branike pa nadpovprečne marčevske temperature. Analiza časovne stabilnosti klimatskega signala z odzivnimi funkcijami in metodo drsečih oken je pokazala, da se je odnos med klimo in širino branike postopoma spreminjal. Bolj ko se približujemo sedanjosti, pomembnejši postaja negativni vpliv nadpovprečnih temperatur v marcu (branike so ožje) in bolj se izgublja pomen nadpovprečne temperature v juniju. Na nekaterih ploskvah se vplivu nadpovprečnih junijskih temperatur pridruži še vpliv nadpovprečno toplega maja. Rezultati kažejo, da se na zgornji gozdni meji dogajajo spremembe v smeri zgodnejšega začetka vegetacijske sezone, s tem pa so drevesa izpostavljena večjemu tveganju poznih pozeb.The relationship between larch (Larix decidua Mill.) tree-ring widthsand climate was studied on 7 selected locations in the southeastern partof the Alps (Slovenian Alps). Analysis was performed for the 1900-2003 period, when 13 positive common and 17 negative common pointer years were identified. The response function analysis showed significant positive response (wide tree ring) of larch to above-average temperature in June and significant negative response to above-average temperature in March. Temporal stability of climate-growth relationship was tested using the Forward Evolutionary Interval Method (part of Bootstrapped response function procedurein DendroCLIM 2002). Results showed changes in response to climate asthe time approached 2003. Influence of the above-average temperature in Junewas becoming less important, while the above-average temperature in May appeared to gain importance. Besides, negative influence of the aboveaverage temperature in March was progressively gaining in its importance. Change of response is directly connected to the increasing winter temperatures at high altitudes in the last 10-15 years

Larch (Larix decidua Mill.) chronology for the Southeastern Alp

Predstavljena je sestava dolge kronologije širin branik za macesen v JV Alpah.Kronologija temelji na izvrtkih živih dreves in je dolga 333 let, največja pokritost je 74, več kot štirje vzorci obstajajo na 95 % in več kot 13 vzorcev na 74 % celotne dolžine. Samo prvih 8 let kronologije temelji na enem samem drevesu. Vzorci za kronologijo so bili nabrani na 6 tipičnih macesnovih rastiščih (Komna, Uskovnica, Vršič, Jezersko, Veža in Viševnik). Macesnova kronologija živih dreves se dobro ujema z nekaterimi tujimi macesnovimi kronologijami za območje Alp (Italija, Avstrija, Nemčija Francija in Švica). Analiza značilnih let je dala 34 pozitivnih in 87 negativnih značilnih let. Preliminarni testi so pokazali tudi dobro odzivnost na klimatska nihanja. Čeprav smo analizirali tudi nekaj zelo starih dreves (400+ branik), jih v končno kronologijo nismo vključili. Razlog za to so bile številne manjkajoče in lažne branike ter rastne anomalije.A 333 years long living larch tree ring chronology for the Southeastern Alps is presented. The highest chronology depth is 74, more than four samples are present in 95% of the entire length, and only the first eight years are based only on a single tree. Six sampling locations were chosen along the Alpine ridge in Slovenia, i.e.: Jezersko (two plots), Komna, Vršič, Veža, Viševnik and Uskovnica. Compiled chronology synchronise well with the selection of foreign chronologies (France, Italy, Austria, Germany and Switzerland). New Slovene larch chronology has 34 positive and 87 negative pointer years. Preliminary tests revealed good climatic signal as well. Although some very old trees (400 yrs. +) have been found, cored and measured, they were not included in this chronology due to many missing rings and various growth irregularities

Multiple tree-ring parameters from Pinus nigra (Arnold) and their climate signal

The first exploration of climate signal in tree-rings of Black pine (P. nigra Arnold), using minimum blue intensity method, is presented. Sampled trees were growing on site Kojnik (Slovenia). For resin extraction and scanning, 5 mm thick cores were prepared. Whole tree-ring widths were measured, as well as the width and density of early- and latewood. To remove age trend and influence of non-climatic factors, raw measurements were standardized using spline function. In density measurements, highly significant correlation values were calculated between May-June summed precipitation and earlywood density (r = 0.64, p<0.001), while maximum latewood density correlates the best with mean June-August temperature (r = 0.42, p<0.01). In width measurements, the highest correlation was calculated between tree-ring width and mean June-August temperature (r = -0.62, p<0.001)

Kronologija jelke (Abies alba Mill.) za območje Pohorja

Dendrochronological investigations were made in silver fir (Abies alba Mill.) from Lovrenc, Pohorje, in the NE Slovenia. Tree ring analyses were made in discs of 25 healthy, adult, dominant or co-dominant silver firs and in cores from roof construction of two older rustic buildings from the same region using a LINTAB measuring device nad a TSAP/X of F. Rinn. We constructed the chronology of trees spanning the period of 1785-1996. The chronology of the old house is spanning the period of 1713-1852 and the chronology of barn 1745-1887. It was shown that the last considerable reconstruction of the house roof took place after the end of the growing period of 1952. The dating of the cores containining the outer ring 1887 confirmed the dating based on the carved inscription "1888". The three chronologies were joined into 284 years long silver fir chronology for Pohorje spanning the period of 1713-1996. It was compared with the Slovene silver fir chronology of the Dinaric region. Despite distance and great differences between the two regions there was shown a statistically confirmed similarity of two chronologies with tBP=9.8, GLK=71% and CDI=398. The chronologies have 21 common negative, 21 positive signature years and one common signature interval. Based on this the constructed chronology may be considered as representative for the whole Pohorje. The two chronologies are expected to be a good base to construct a regional Slovene Silver-fir chronology for dating in whole Slovenia. Two Slovene chronologies were compared with the following European silver fir chronologies: South German, stand 1993 (Becker and Siebenlist 1970Spurk and Friedrich , pers. com.), Bavarian Forest - Germany (Eckstein, Sass 1988), Abetone - Italy (Schweingruber, ITRDB), Bannwald - Switzerland (Schweingruber, ITRDB). Both Slovene chronologies proved to be statistically similar with the two German and the Italian silver fir chronology, but showed no similarity with the Swiss one. The Pohorje chronology correlates better with both German ones and the Dinaric chronology correlates better with the Italian one

The influence of climate on tree-ring maximum latewood density in Norway spruce (Picea abies (L.) Karst.) at two sites in Slovenia

Navadna smreka (Picea abies (L.) Karst.) je zaradi svoje razširjenosti, zgradbe lesa in dolge življenjske dobe razmeroma pogost objekt dendrokronoloških raziskav. Doslej objavljene slovenske smrekove kronologije so bile sestavljene na podlagi širin branik, prispevek pa predstavlja prve denzitokronologije v Sloveniji in opisuje metodo določanja maksimalne gostote kasnega lesa branike (MXD). Raziskava je potekala na dveh različnih smrekovih rastiščih - Pokljuki in Sorškem polju. Na obeh lokacijah smo v vzorec zajeli po 13 dreves. Rezultati, dobljeni na Sorškem polju, so pokazali višje vrednosti MXD in manjše število značilnih let. Analiza je pokazala tudi pozitivno korelacijo med MXD in temperaturami v avgustu in septembru.Norway spruce (Picea abies (L.) Karst.) is frequently the object of dendrochronological research owing to its distribution, wood structure and longevity. The Norway spruce chronologies published in Slovenia so far have been based on tree-ring widths. This article presents the first density chronologies and describes the method of determining maximum latewood density (MXD). Two different sampling sites were selected (Pokljuka and Sorško polje) and 13 sampling cores were taken from each site. The results showed positive correlation between MXD and temperatures in August and September. Furthermore,higher MXD values and less pointer years were observed at the lowland Sorško polje site

Macro EWVA - an effective tool for analysis of earlywood conduits of ring porous species

V članku je predstavljena uporabnost programa ImageJ v lesni anatomiji. Njegova glavna prednost sta prosta dostopnost ter možnost vključevanja dodatnih vtičnikov in makrov. Program ImageJ smo uporabili kot platformo za razvoj makra EWVA za avtomatizirano prepoznavanje ranega lesa ter hitro in učinkovito analizo trahej venčastoporoznih listavcev. Uporabnost makra EWVA predstavljamo na primeru dveh dobov iz sestoja v Mlačah. V zaključku razpravljamo o prednostih in slabostih uporabljene metode.In this paper, program ImageJ and its application in tree-ring anatomy is presented. The main advantage of the program is its availability and possibility to add additional tools and macros. Platform of ImageJ programme was used to develop macro EWVA for automatized recognition of earlywood and effective analysis of vessels of ring porous species. Use of EWVA macro is presented in a case study of two pedunculate oaks from the Mlače stand. Advantages and disadvantages of the presented method are discussed

Dendroecological study of spruce (Picea abies (L.) Karst.) growth around two coal-fired power plants

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 učinkovitejšamanj pa se je rast izboljšala v okolici TET, kjer je 360 m visoki odvodnik emisije samo razpršil na večje območje.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

Stabilna ogljikova izotopa v branikah smreke (Picea abies (L.) Karst.) na dveh rastiščih v Sloveniji

Stable isotopes in tree rings are an important tool in climate reconstruction and in studies of tree response on environmental factors in the past, similar like maximum latewood density, tree ring width and other tree ring parameters.In this article we present stable carbon isotopes physiology and the first two Slovenian d13C chronologies for Norway spruce (Picea abies (L.) Karst.) growing at two sites with different ecological conditions. Five trees were sampled at Pokljuka alpine site and three at Sorško polje lowland plantation. d13C values were compared with CRU TS 1.2 meteorological data-set,which provides information on climate in Europe for the 1901-2000 period at a 10ć spatial resolution. Results of correlation analysis for both sites revealed similar average d13C values, which are in strong negative correlation with amount of precipitation and positive correlation with temperatures in the growing period. Temporal stability of the correlation between precipitation and d13C values in July is significant for both sites, where as the stability of d13C - temperature relationship is significant only for the Sorško polje site.Stabilni izotopi v branikah dreves so, tako kot širine branik, maksimalna gostota kasnega lesa in drugi parametri branike, pomembno orodje pri rekonstrukciji klime v preteklosti in preučevanju odziva dreves na okoljske dejavnike. V prispevku predstavljamo fiziologijo stabilnih ogljikovih izotopovin prve slovenske d13C-kronologije smreke (Picea abies (L.) Karst.) nadveh lokacijah z različnimi ekološkimi razmerami. Na visokogorskem rastišču Pokljuka smo odvzeli vzorce petih, v nižinskem nasadu na Sorškem polju pa trehdreves. Vrednosti d13C smo primerjali s podatki CRU TS 1.2 meteorološke baze, ki vsebuje podatke o klimi za obdobje 1901-2000 v Evropi, s prostorsko ločljivostjo10ć. Rezultati korelacijske analize so pokazali, da je na obeh rastiščih povprečna d13C-vrednost podobna in v močni negativni korelaciji s količino padavin ter v pozitivni korelaciji z visokimi temperaturami v vegetacijski sezoni. Stabilnost korelacijske povezanosti med padavinami v juliju in d13C je značilna za obe lokaciji, medtem ko se stabilnost odnosa d13C- temperature kaže le na Sorškem polju

Stable carbon isotopes in Norwey spruce (Picea abies (L.) Karst.) tree rings at two sites in Slovenia

Stable isotopes in tree rings are an important tool in climate reconstruction and in studies of tree response on environmental factors in the past, similar like maximum latewood density, tree ring width and other tree ring parameters.In this article we present stable carbon isotopes physiology and the first two Slovenian d13C chronologies for Norway spruce (Picea abies (L.) Karst.) growing at two sites with different ecological conditions. Five trees were sampled at Pokljuka alpine site and three at Sorško polje lowland plantation. d13C values were compared with CRU TS 1.2 meteorological data-set,which provides information on climate in Europe for the 1901-2000 period at a 10ć spatial resolution. Results of correlation analysis for both sites revealed similar average d13C values, which are in strong negative correlation with amount of precipitation and positive correlation with temperatures in the growing period. Temporal stability of the correlation between precipitation and d13C values in July is significant for both sites, where as the stability of d13C - temperature relationship is significant only for the Sorško polje site