Provider: - Institution: - Data provided by Europeana Collections- U radu su procijenjene zalihe, tokovi i bilanca ugljika šumskog ekosustava hrasta lužnjaka (Quercus robur L.) u Pokupskom bazenu. ...Primjenom metode kronosekvence utvrđena je dinamika razvoja zaliha ugljika tijekom životnog vijeka sastojine hrasta lužnjaka, odnosno od 5. do 168. godine starosti. Također je procijenjena i bilanca ugljika odabranog šumskog ekosustava, kao neto razlika pohranjenog i oslobođenog ugljika te je utvrđena njena unutar-sezonska dinamika te dinamika tijekom razvoja šumske sastojine. Na temelju podataka o uređajnom razredu hrast lužnjak iz sjemena, u gospodarskoj jedinici Jastrebarski lugovi, utvrđeno je stvarno stanje zaliha i bilance ugljika u razdoblju trajanja važeće Osnove gospodarenja, od 2004. do 2013. godine. Primjenom različitih scenarija obnove provedena je projekcija razvoja pojedinih sastojina odabranog uređajnog razreda za pet 10-godišnjih razdoblja, od 2004. do 2053. godine, te su utvrđene bilance ugljika ostvarene primjenom navedenih scenarija.Na razini sastojine procijenjena je zaliha ugljika u živoj biomasi, mrtvom drvu (sušci, panjevi i drvni otpad) te šumskoj prostirci i organskoj tvari mineralnog dijela tla. Također su na razini sastojine procijenjeni glavni tokovi ugljika: neto primarna produkcija drvne biomase, produkcija lista i plodova, produkcija sitnog korijena, ukupna i heterotrofna respiracija tla te dekompozicija nadzemne biomase mrtvog drva. Uz pretpostavku da je bilanca ugljika na razini sastojine jednaka neto produkciji ekosustava, ista je procijenjena kao razlika ukupne neto primarne produkcije i ukupne heterotrofne respiracije ekosustava. Na razini uređajnog razreda utvrđeni su i gubitci ugljika sječom, a bilanca ugljika je procijenjena kao razlika neto produkcije ekosustava i gubitaka ugljika sječom.Raspodjela zaliha ugljika po glavnim sastavnicama šumskog ekosustava hrasta lužnjaka mijenja se tijekom životnog vijeka na način da su u sastojinama I. dobnog razreda najveće zalihe ugljika pohranjene u organskoj tvari tla, a u starijim sastojinama su najveće zalihe ugljika pohranjene u živoj biomasi. Zalihe u organskom horizontu tla povećavaju se sa starosti sastojine, dok su zalihe ugljika u mrtvom drvu najveće u najmlađim i starim sastojinama, a najniže u srednjodobnim i zrelim sastojinama. Za zalihe ugljika u mineralnom dijelu tla nije utvrđena statistički značajna ovisnost o starosti sastojine čime je potvrđena pretpostavka da u šumskom ekosustavu hrasta lužnjaka dosadašnji način gospodarenja nema značajniji utjecaj na zalihe ugljika u mineralnom dijelu tla. Sastojina hrasta lužnjaka, kada je uspješno obnovljena, postaje ponor ugljika već u vrlo ranoj dobi, između 5-te i 13-te godine starosti, što je posljedica veće ukupne neto primarne produkcije u odnosu na ukupnu heterotrofnu respiraciju, i sastojina ostaje ponor ugljika i nakon dobi od 160 godina. Kulminacija bilance ugljika, zabilježena kod sastojine u dobi od 53 godine, odgovara kulminaciji produkcije drvne biomase.Na temelju dobivenih rezultata izrađeni su jednostavni modeli ovisnosti pojedinih zaliha i tokova ugljika o lako dostupnim varijablama šumske sastojine (dob sastojine, drvna zaliha) koji su poslužili za procjenu zaliha i bilance ugljika u stvarnoj šumi hrasta lužnjaka. U uređajnom razredu hrast lužnjak iz sjemena u gospodarskoj jedinici Jastrebarski lugovi, u razdoblju od 2004. do 2013. godine ostvarena je pozitivna bilanca ugljika. U simulacijskom razdoblju od 2004. do 2053. također je ostvarena kumulativna pozitivna bilanca ugljika i izdvojen je scenarij obnove koji najviše odgovara suvremenim zahtjevima potrajnog gospodarenja šumama.- Within this research carbon stocks, fluxes and carbon balance was estimated in Pedunculate Oak (Quercus robur L.) forest ecosystem in river Kupa basin. Using chronosequence method carbon stocks dynamic during a life-time of Pedunculate oak stand was determined, from the age of 5 to 168 years. Also, carbon balance of selected forest ecosystem was estimated as difference between accumulated and released carbon, and intra-seasonal dynamic as well as dynamic during a development of stand was determined. On the basis of available data on the management class of Pedunculate Oak high stand, current state of carbon stocks and carbon balance was estimated for the period of current management plan, from the year 2004 to 2013. Using different scenarios of defining area for regeneration, development projection of individual stands of selected management class was made for five 10-years periods, from the year 2004 to 2053, and different carbon balance estimates were obtained for each scenario.At the stand level carbon stocks in live biomass, dead wood (snags, stumps and woody debris), forest floor and organic carbon in mineral soil were estimated. Also, at the stand level, main carbon fluxes were estimated: net primary production in woody biomass, leaf and seed production, fine root production, total and heterotrophic soil respiration and decomposition of aboveground dead wood. Net ecosystem production at the stand level was estimated as difference between total net primary production and total heterotrophic respiration, and it is assumed that it is equal to carbon balance. At the management class level carbon losses due to harvest were determined, and carbon balance was estimated as difference between net ecosystem production and carbon losses due to harvest.Carbon stock share in main forest ecosystem pools changes during a stand development in a way that youngest stands store more carbon in soil organic matter then in live biomass, while in older stands more carbon is stored in live biomass then in soil. Carbon stocks in organic layer increase with stand age, while carbon stocks in dead wood are highest in young and older stands, and lowest in middle-aged, mature stands. For carbon stocks in mineral soil layer no statistically significant age-dependent trend was observed. That confirmed the assumption that harvest activities under current management practice in this type of Pedunculate Oak forest ecosystems does not significantly influence carbon stocks in mineral soil layer. Pedunculate Oak stand, when successfully regenerated, becomes carbon sink very early in a development phase, between the age of 5 and 13 years, as a result of higher total net primary production with respect to total heterotrophic respiration, and stands remain carbon sink even after the age of 160 years. Stand reaches greatest carbon sink in the age of 53 years, and it is in accordance with highest woody biomass production.Obtained results were used to develop simple models of carbon stocks and fluxes as a function of easily obtained stand variables (stand age, growing stock) which were then used to estimate carbon stocks and carbon balance in real forest. In Pedunculate Oak high stand management class, in management unit Jastrebarski lugovi, positive carbon balance was estimated for the period from 2004 to 2013. For the simulation period from 2004 to 2053, also a positive cumulative carbon balance was estimated, and appropriate scenario that meets the needs of modern sustainable forest management was recognized.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
