CAJ | 학술논문

采用长期定位跟踪实测方法,比较分析了我国东北温带森林4个水热状况不同的立地条件(红松(Pinus koraiensis)人工林、硬阔叶林、蒙古栎(Quercus mongolica)林和林外空旷地)下11个温带树种粗木质残体(CWD)分解初期3年中的碳氮动态及其影响因子.测定树种包括:白桦(Bemla platyphylla)、山杨(Populus davidiana)、紫椴(Tilia amurensis)、胡桃楸(Juglansmandshurica)、蒙古栎、色木槭(Acer mono)、春榆(Ulmus japonica)、红松、黄檗(Phellodendron amurense)、兴安落叶松(Larixgmelinii)和水曲枊(Fraxinus mandshurica).结果表明:在分解过程中,所有树种CWD的碳浓度没有明显变化(p>0.05),但其干重、碳密度、氮浓度和氮密度均随分解进程不同程度地减小,碳氮比(C/N)则增大,而且树种间差异显著(p<0.001).针叶树种的CWD分解速率显著地低于阔叶树种,其中自桦的3年CWD干重损失率(65%)约为兴安落叶松(22%)的3倍.径级大的CWD分解较慢.CWD分解与碳氮释放均与CWD的初始N含量呈正相关,而与初始C/N呈负相关.4个立地条件下CWD的干重和碳氮含量的变化差异不显著,均表现出一致的变化趋势.该研究指出,在分解初期的前3年中,CWD基本上是一个碳源和氮源.
채용장기정위근종실측방법,비교분석료아국동북온대삼림4개수열상황불동적입지조건(홍송(Pinus koraiensis)인공림、경활협림、몽고력(Quercus mongolica)림화림외공광지)하11개온대수충조목질잔체(CWD)분해초기3년중적탄담동태급기영향인자.측정수충포괄:백화(Bemla platyphylla)、산양(Populus davidiana)、자단(Tilia amurensis)、호도추(Juglansmandshurica)、몽고력、색목축(Acer mono)、춘유(Ulmus japonica)、홍송、황벽(Phellodendron amurense)、흥안락협송(Larixgmelinii)화수곡앙(Fraxinus mandshurica).결과표명:재분해과정중,소유수충CWD적탄농도몰유명현변화(p>0.05),단기간중、탄밀도、담농도화담밀도균수분해진정불동정도지감소,탄담비(C/N)칙증대,이차수충간차이현저(p<0.001).침협수충적CWD분해속솔현저지저우활협수충,기중자화적3년CWD간중손실솔(65%)약위흥안락협송(22%)적3배.경급대적CWD분해교만.CWD분해여탄담석방균여CWD적초시N함량정정상관,이여초시C/N정부상관.4개입지조건하CWD적간중화탄담함량적변화차이불현저,균표현출일치적변화추세.해연구지출,재분해초기적전3년중,CWD기본상시일개탄원화담원.
Aims Our objectives were to quantify the loss of coarse woody debris (CWD) mass, carbon (C) and nitrogen (N) and main influencing factors during the first three years of CWD decomposition of 11 major tree species in Chinese temperate forests based on an in situ long-term experiment.Methods The experimental design was completely randomized blocking design of 11 species × 6 blocks × 4 sites. The species were white birch (Betula platyphylla), Amur linden (Tilia amurensis), Korean pine (Pinus koraiensis), Manchurian walnut (Juglans mandshurica), cork-tree (Phellodendron amurense), Mongolian oak (Quercus mongolica), Dahurian larch (Larix gmelinii), Mono maple (Acer mono), Manchurian ash (Fraxinus mandshurica), popular (Populus davidiana), and Japanese elm (Ulmus japonica). The four sites with various environmental conditions were Mongolian oak forest, hardwood forest, Korean pine plantation and open field. We randomly selected three CWD samples for each tree species in each site and cut a 5 cm-thick disc at the end of the CWD in October 2005 and October 2008, respectively, for measuring C concentration, C density, N concentration, N density, C/N ratio and CWD density.Important findings The C concentration of CWD did not change significantly during the early stage of CWD decomposition for all species (p > 0.05). The CWD mass, C density, N concentration and N density decreased during decomposition, whereas the C/N ratio increased. The differences in these parameters among the species were significant (p < 0.001). The coniferous species had significantly lower decomposition rates than the broad-leaved species. There was a negative correlation between size and decay rate. Loss of mass and release of C and N of the CWD were positively correlated with the initial N content, but negatively correlated with the initial C/N ratio. The changes of mass and C and N content of CWD had similar patterns at the four sites. Our results indicated that the CWD tended to be C and N sources during the first 3-year decomposition process.