Accumulation and decay dynamics of coarse woody debris in a Japanese old-growth subalpine coniferous forest
Accumulation and decay dynamics of coarse woody debris in a Japanese old-growth subalpine coniferous forest
复制标题
DOI：
10.1007/s11284-013-1120-3
复制
发表时间：
2014-03-01
影响因子：
2
通讯作者：
Takeda, Hiroshi
中科院分区：
文献类型：
--
作者：
Fukasawa, Yu;Katsumata, Shingo;Takeda, Hiroshi
与欧洲和北美洲的寒带和温带地区相比，人们对亚洲温带地区的粗木屑（CWD）存量和腐烂过程知之甚少。我们估算了日本亚高山针叶林的针叶 CWD 存量（原木和断枝）、腐烂率和过程，以及导致腐烂过程的真菌物种。 CWD质量为42.4 Mg ha(-1)，是亚洲温带地区以往记录的最大数据。使用CWD年输入除以CWD积累计算出的衰减率为0.036年(-1)，而按时间顺序测量的衰减率为0.020-0.023年(-1)。腐烂过程分为两个阶段，其特征是不同的主要有机化学成分。在第一阶段，酸不可水解的残留物和全纤维素同时腐烂，暗示了白腐过程。在第二阶段，全纤维素选择性分解，AUR 积累，提示褐腐过程。养分（N、P、K、Na、Mg 和 Ca）在第一阶段被矿化，但在第二阶段被固定。研究区 CWD 记录了 26 个真菌类群的子实体。在第一阶段占主导地位并被称为白腐真菌的Trichaptum abietinum和T. fuscoviolaceum被认为是第一阶段木质纤维素的主要分解者。尽管没有已知的强木材分解者主导第二阶段，但硫磺乳杆菌（Laetiporus sulfureus）和凯氏寡孔菌（Oligoporus caesius）（称为褐腐真菌）预计将参与第二阶段全纤维素的选择性分解。
Far less is known about the coarse woody debris (CWD) stock and decay process in temperate Asia compared with that in boreal and temperate Europe and North America. We estimated coniferous CWD stock (logs and snags), decay rate and process, and fungal species responsible for the decay process in a Japanese subalpine coniferous forest. The CWD mass was 42.4 Mg ha(-1), which was the greatest among the previous data recorded in temperate Asia. The decay rate calculated using the annual input of CWD divided by CWD accumulation was 0.036 year(-1), whereas the decay rate when measured chronosequentially was 0.020-0.023 year(-1). The decay process was divided into two phases characterized by different dominant organic chemical constituents. In the first phase, both acid-unhydrolyzable residue and holocellulose decayed simultaneously, suggestive of the white-rot process. In the second phase, holocellulose was selectively decomposed and AUR accumulated, suggestive of the brown-rot process. Nutrients (N, P, K, Na, Mg, and Ca) were mineralized in the first phase but immobilized in the second phase. The fruiting bodies of 26 taxa of fungi were recorded as occurring on CWD in the study area. Trichaptum abietinum and T. fuscoviolaceum, which dominated in the first phase and are known as white-rot fungi, were assumed to be the main decomposers of lignocellulose in the first phase. Although no known strong wood decomposers dominated the second phase, Laetiporus sulphureus and Oligoporus caesius, known as brown-rot fungi, were expected to participate in the selective decomposition of holocellulose in the second phase.