美国南卡罗来纳州森林湿地十种典型植物凋落叶的分解特征

发布时间：2018-04-25 11:28

  本文选题：森林湿地 + 凋落叶　； 参考：《生态学报》2017年07期

【摘要】：凋落叶分解是控制森林湿地物质循环的重要生态过程,是全球C、N等元素循环的重要一部分。以美国南卡罗来纳州10种典型植物的凋落叶为研究对象,通过2a的分解实验测定分解阶段凋落叶的生物量残留率、分解速率常数k和C、N残留百分比,探讨初始凋落叶化学性质对分解速率常数k的影响。结果表明:(1)十种凋落叶生物量在两年内降解至初始的14.5%—66.2%,种间差异可达4倍以上;分解速率常数k在0.26—1.64a~(-1)之间,针叶分解速率阔叶分解速率;(2)分解速率常数k与初始凋落叶酸溶性组分(AS)极显著正相关(P0.001),与初始C含量、酸不溶组分(AIF)和AIF/N比均显著负相关(P0.05);(3)凋落叶C残留百分比持续下降至10.2%—66.1%,而N残留百分比因物种与分解阶段不同呈现不同变化规律。结果表明,森林湿地中凋落叶初始C组分差异是其分解速率的种间极大差异的主要原因,评估森林湿地的C、N循环应充分考虑种间差异。
[Abstract]:Leaf litter decomposition is an important ecological process to control the material cycle in forest wetlands and is an important part of the global cycling of elements such as Con. The litter leaves of 10 typical plants in South Carolina, USA were studied. The biomass residue rate, the decomposition rate constant k and the residual percentage of Con N were determined by 2a decomposition experiment. The effect of chemical properties of initial litter on the decomposition rate constant k was studied. The results showed that the biomass of 10 littered leaves degraded to the initial 14.5-66.2 in two years, and the interspecific difference was more than 4 times, and the decomposition rate constant k was 0.26-1.64a ~ (-1). The decomposition rate constant k was positively correlated with the initial folic acid soluble component (ASS) and the initial C content. The percentage of C residue in littered leaves decreased to 10.2-66.1%, while the percentage of N residues varied from species to decomposition stage. The results showed that the difference of initial C component of litter leaves in forest wetland was the main reason for the great difference of decomposition rate among species, and to evaluate the Con N cycle of forest wetland, the difference between species should be fully taken into account.
【作者单位】： 北京大学深圳研究生院;北京大学城市与环境学院;
【基金】：国家自然科学基金资助项目(31321061)
【分类号】：S714
，

本文编号：1801115