草海湿地流域优势树种凋落物叶分解与水文特征研究

Research on Leaf Litter Decomposition and Hydrological Characteristics of Dominant Tree Species in the Caohai Wetland Watershed

采用凋落物分解网袋法对草海湿地流域森林优势植物青冈（Cyclobalanopsis glauca）、白栎（Quercus fabri）、桤木（Alnus cremastogyne）、滇杨（Populus yunnanensis）、云南松（Pinus yunnanensis）和杉木（Cunninghamia lanceolata）凋落物叶分解残留率、分解率、分解模型及凋落物叶分解过程中的水文特征进行研究。结果表明：（1）分解12个月后,凋落物叶累积分解率分别为青冈（24.0±1.4）%,白栎（24.1±2.0）%,桤木（26.6±2.6）%,滇杨（26.0±0.7）%,云南松（13.8±2.6）%,杉木（13.8±0.9）%,凋落物叶累积分解率差异极显著（F=10.28,P〈0.01）。（2）凋落物叶分解方程符合Olson指数衰减模型Lr=ae-kt。阔叶植物凋落物叶分解常数在0.019~0.024之间,而针叶植物凋落物叶分解常数在0.011~0.012之间。凋落物叶的分解率受叶形态影响较大,阔叶凋落物分解率明显高于针叶。阔叶植物凋落物叶分解半衰期和分解95%所需时间在2.27~3.06年和10.46~13.16年,针叶植物叶凋落物半衰期和分解95%所需时间在4.61~5.20年和20.60~20.64年。（3）凋落物叶持水率（Rl）与分解残留率（Lr）呈显著线性相关关系Rl=aLr＋b（P〈0.05）。（4）土壤含水率（Rs）与凋落物叶持水率（Rl）呈显著反函数相关关系Rs=a/Rl＋b（P〈0.05）。

Using the method of leaf litter decomposition bag to study the litter decomposition＇s residual rate, decomposition rate, regression model and hydrographic trait by decomposition process. The dominant tree species（e, g. , Cyclobalanopsis glauca , Quercus fabri , Alnus cremastogyne , Populus yunnanensis , Pinus yunnanensis and Cunninghamia lanceolata） in Caohai wetland watershed forest was selected as the research object. The result showed that： （1）The leaf litter accumulation decomposition rate was （24. 0±1. 4） %（Cyclobalanopsis glauca ）, （24.1±2.0） % （Quercus fabri） , （26.6± 2.6） % （Alnus crernastogyne） , （26.0 ± 0. 7） % （Populus yunnanensis）, （13.8 ± 2.6） % （Pinus yunnanensi ） and （13.8 ± 0.9） %（Cunninghamia lanceogata ）, respectively by the decomposition 12 months later, the litter decomposition rate of leaf accumulated had extremely significant difference （F= 10. 28, P〈0. 01）. （2） The leaf litter decomposition equation conformed to the Olson Exponential decay model（Lr =ae^-kt）. The leaf litter decomposition constants of broadleaved plant and conifer plant were 0. 019-0. 024 and 0. 011-0. 012, respectively. The leaf litter decomposition rate was influenced by leaf form, the leaf litter decomposition rate of broadleaved plant was significantly higher than that of conifer leaf plant. T0.5 and T0.95 in broadleaved plant was 2.27-3.06 years and 10. 46-13.16 years, that in conifer plant was 4.61-5.20 years and 20. 60 - 20. 64 years. （3）The leaf litter water-holding rate （Rl） and decomposition residual rate（Lr） showed a significant linear relationship（Rl=aLr＋b, P〈0.05）. （4）The soil moisture（Rs） and leaf litter water-holding rate（Rl） showed a significant inverse function correlation（Rs = a/Rl ＋b, P〈0.05）.