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

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

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

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

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

Zgradba in razvoj gozdnih ekotopov v Udin Borštu

V diplomskem delu smo zasnovali informacijski sistem, s pomočjo katerega smo ocenili, da je Udin boršt prvobitno gozdno zemljišče, krčenje gozda pa je biloprisotno predvsem v njegovem južnem delu in v bližini naselij. Površina gozda se v zadnjih 250 letih ni bistveno spremenila, pač pa se je spreminjala njegova zgradba. Z opuščanjem steljarjenja in načrtnim gojenjem gozdov se je povečala lesna zaloga Udin boršta in delež listavcev v njej. Danes prevladujejo sestoji v obnavljanju, ki so pretežno pomanjkljivo negovani in spremenjeni, prevladujoči drevesni vrsti sta rdeči bor in smreka. Na podlagi podatkov majhnega števila stalnih vzorčnih ploskev smo dobili prevelike vzorčne napake, da bi lahko sklepali o značilnih razlikah med posameznimi ocenjevanimi stratumi in ekotopi. Glavni dejavniki, ki opredeljujejo ekotope vUdin borštu, so relief, prst in gozdne združbe. Varstveni režimi, ki veljajo v krajinskem in spominskem parku Udin borštu določajo, da je gospodarjenje z gozdovi dovoljeno po določilih potrjenih gozdnogospodarskih načrtov.In this graduation thesis we designed an information system which helped us asses that Udin boršt has always been covered in forest vegetation and that clearing of forest was mainly present in its southern part and in the vicinityof settlements. Although the surface area of the forest has not changed substantially in the last 250 years, its structure has. With abandoning of litter gathering and planned silviculture of cultivating forests, the growing stock at Udin boršt and the share of broadleaves has increased. Today the predominantly insufficiently tended and altered structures in revival prevail. The dominant species are pine and spruce. Basedon coarsesampling net (500 x 250 m) it was not possible to confirm the differences between management classes or strata. The main factors that defineecotopes in Udin boršt are relief, soil and forest asociations. The protection regimes, which are valid in landscape and memorial park Udin boršt,define that managing of forests is allowed by the provisions of certified forest managing plans