Abstract | Prirodi blisko uzgajanje šuma je temelj šumarstva jugoistočne Europe. Razumijevanje silvidinamike prašumskih sastojina je važna teorijska podloga za razvoj konceptualnih modela prirodi bliskog gospodarenja šumama. Zbog malog broja očuvanih lokaliteta koje imaju karakter prašuma za većinu vrsta drveća nedostaju potrebni podaci kako bi se istražila njihova prirodna silvidinamika. Trenutno najbolje očuvane prašumske sastojine crnoga bora (Pinus nigra J. F. Arnold) i munike (Pinus heldreichii H. Christ.) možemo pronaći na visokim predjelima dinarskih planina u Sloveniji, Hrvatskoj, Bosni i Hercegovini, Crnoj Gori, Albaniji i Makedoniji. Dosadašnja istraživanja prašuma i starih šuma crnoga bora i munike na području Dinarida su rijetka i nesustavna. Stoga su glavni ciljevi ovoga istraživanja analizirati silvidinamiku i odgovor prašuma i starih šuma crnoga bora i bora munike na klimatske promjene na području jugoistočnih Dinarida. Istraživanje je obavljeno u Dinarskom gorju od sjeverozapada prema jugoistoku. Ukupno su postavljene 33 pokusne plohe u prašumama i starim sastojinama crnog bora i munike. Rezultati istraživanja pokazuju da su prašumske sastojine crnog bora i munike raznodobne, maksimalne starosti kod crnog bora od 501 godine i 625 godina kod munike. Premda pridolaze na vrlo strmim i nedostupnim terenima njihova produkcija variara od 150 do 1300 m³/ha. Sastojine crnoga bora na zapadnim Dinaridima imaju manji volumen i starosti u odnosu na sastojine na istočnim lokalitetima i većim nadmorskim visinama. Temeljnica i drvna zaliha u istraživanim sastojinama crnog bora i munike je u optimalnim vrijednostima za stanišne uvjete što ukazuje da sastojine postižu maksimalnu proizvodnu sposobnost bez obzira na oskudne stanišne prilike. Utjecaj klime na rast stabala obje istraživane vrste je značajan. Crni bor za razliku od munike pokazuje značajnu prilagodbu na klimatske promjene na način da iskorištava visoke tempertaure zraka u proljeće (veljača-ožujak) te time počinje sa ranijim rastom naročito nakon 1960. godine. Stoga sve veće temperature zraka u ljetnom periodu (lipanj-kolovoz) ne ograničavaju njegov rast. Na rast munike pozitivno utječu oborine u ljetnom periodu, dok temperatura u ljeto reducira rast ove vrste. Kako bilo iz provedenih analiza možemo zaključiti da se crni bor prilagodio recentnim promjenama klime te ih iskoristio na najbolji način. Analizama stabilnih vodikovih izotopa iz celuloze drva napravljene su rekonsturkcije indeksa jačine suše (scPDSI) za cijele Dinaride. Rekonsturkcija pokazuje da su jačine i intenzitet suša sve veći tijekom posljednjih 250. godina te da je trend suša u porastu. Sukladno rezultatima provedenih analiza možemo zaključiti da su obje istraživane vrste a posebice crni bor otporne na suše te da se kao takve trebaju koristii za pošumljavanja i uzgajanje na teškim i nedostupnim krškim terenima Dinarsgkog gorja. |
Abstract (english) | Close-to-nature forest management is the basis of forestry in Southeastern Europe. Understanding the silvidynamics of primary forests is an important theoretical basis for the development of conceptual models of close-to-nature forest management. Due to the small number of preserved localities that have the character of a primary forests, the necessary data are missing for most tree species. Currently, the best-preserved primary forests of black pine (Pinus nigra J.F. Arnold) and bosnian pine (Pinus heldreichii H. Christ.) can be found in the remote areas of the Dinaric mountains in Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania and Macedonia. Previous studies of primary and old-growth forests of black and bosnian in the area of the Dinarides are rare and unsystematic. Therefore, the main goals of this research are to analyze the silvidynamics and response of primary and old-growth forests of black pine and bosnian pine to climate change in the southeastern Dinarides. The research was carried out covering the gradient of the Dinaric Mountains from the northwest to the southeast. A total of 33 plots were set up in primary and old-growth stands of pines. The results of the research indicate that the forest stands of black pine and bosnian pine are of various ages, with a maximum age of 501 years for black pine and 625 years for bosnian pine. Although they grow on very steep and inaccessible terrain, their production varies from 150 to 1300 m3/ha. The stands of black pine in the western Dinarides have a smaller volume and age compared to the stands in eastern localities and at higher altitudes. Basal area and growing stock in the researched stands of black pine and bosnian pine are at optimal values for the habitat conditions, which indicates that the stands achieve maximum production capacity regardless of scarce habitat conditions. The influence of climate on the growth of trees of both researched species is significant. The black pine, unlike the bosnian pine, shows a significant adaptation to climate changes in a way that it takes advantage of the high air temperatures in the spring (February-March) and thus starts growing earlier, especially after 1960. Therefore, increasing air temperatures in the summer period (June-August) do not limit its growth. The growth of bosnian is positively influenced by precipitation in the summer period, while the temperature in the summer reduces the growth of this species. However, from the analyzes carried out, we can conclude that the black pine has adapted to recent climate changes and used them in the best way. The drought severity index (scPDSI) reconstructions for the entire Dinarides were made by analyzes of stable hydrogen isotopes from wood cellulose. The reconstruction shows that the strength and intensity of droughts have been increasing over the last 250 years and that the trend of droughts is increasing. According to the results of the analysis, we can conclude that both researched species, especially the black pine, are resistant to droughts and that as such they should be used for afforestation and cultivation on the difficult and inaccessible karst terrains of the Dinars Mountains in order to mitigate the consequences of climate change and possibly benefit from them. |