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本研究分析了亚热带常绿阔叶林两个重要林型-针叶林与阔叶林在凋落物降解-温度关系的差异。研究表明,低温处理下阔叶林内微生物降解者所引起的凋落叶失重量高于针叶林,然而高温处理下两种林型内叶片失重量并未表现出显著差异。温度升高未引起针叶林内叶片失重量的变化,却显著降低了阔叶林内叶片失重量。低温处理下阔叶林内微生物功能群产生的木质素失重较针叶林高,但高温处理并未引起两林型内木质素失重的差异。温度升高提高两林型内木质素的降解。另外,两种温度处理下,阔叶林内微生物降解者功能群引起的碳水化合物降解高于针叶林。温度升高减少了阔叶林内碳水化合物降解,但并未改变针叶林内碳水化合物降解水平。尽管多数微生物降解酶活性与凋落物失重之间存在较强的相关性,但大多数酶对林型和温度的反应与叶片降解对林型和温度的反应不一致。原因在于叶片与其有机组分的降解是由多种降解酶共同作用的结果。总体上来说,针叶林与阔叶林表现出不同的温度-降解关系。
This study analyzed the differences of litter degradation - temperature between two coniferous evergreen forest types, coniferous forest and broad - leaved forest. The results showed that the weight loss of litter caused by microbial degradation in broadleaf forest was higher than that in coniferous forest under low temperature treatment. However, the weight loss of inner leaves of two forest types did not show significant difference under high temperature treatment. The increase of temperature did not cause the change of leaf weight loss in coniferous forest, but significantly reduced the weight loss of leaf in broad-leaved forest. Under low temperature treatment, the weight loss of lignin produced by functional groups of broad-leaved forest was higher than that of coniferous forest. However, the high temperature treatment did not cause the difference of weight loss of lignin within the two forest types. Increasing the temperature increases the degradation of lignin in two forest types. In addition, under the two temperature treatments, the degradation of carbohydrates by the functional groups of the microorganisms in the broad-leaved forest was higher than that of the coniferous forest. Increasing temperature reduced the degradation of carbohydrates in broad-leaved forest, but did not change the level of carbohydrate degradation in coniferous forest. Although most of the activities of microbial degrading enzymes are strongly correlated with litter weight loss, most of the enzyme responses to forest type and temperature are inconsistent with the response of leaf type to temperature and forest type. The reason is that the degradation of the leaves and their organic components is the result of a combination of several degradative enzymes. In general, coniferous forests and broad-leaved forests show different temperature-degradation relationships.