两种热带雨林土壤微生物生物量碳季节动态及其影响因素  

Seasonal fluctuation of soil microbial biomass carbon and its influence factors in two types of tropical rainforests

作　　者：吴艺雪[1,2] 杨效东[1] 余广彬[1,2] 

机构地区：[1]中国科学院西双版纳热带植物园,云南昆明650223 [2]中国科学院研究生院,北京100049

出　　处：《生态环境学报》2009年第2期658-663,共6页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(40671103)

摘　　要：2005年通过样地调查法比较了西双版纳两种类型热带雨林(季节沟谷雨林和石灰山季雨林)的土壤微生物生物量碳季节变化及其与环境因子的关系。结果显示:两林地土壤微生物生物量碳均呈现雨季高于干季,其中石灰山季雨林具有明显的季节差异,并在干、雨季都显著高于季节沟谷雨林。相关分析表明:两林地土壤微生物生物量碳的变化与土壤温湿度、相同月凋落量变化没有显著的相关关系,但与提前两个月的凋落量波动有正相关关系。说明雨林土壤微生物生物量碳的波动周期比凋落量滞后,其季节变化受森林凋落量节律的影响。石灰山季雨林土壤微生物生物量碳较季节沟谷雨林高的主要原因可能与其具有较高的土壤有机碳、氮和pH值,以及主要树种凋落物的C/N比较低有关,但相关机制还需进一步研究。This study compares the seasonal variation of soil microbial biomass carbon and its relationship with soil temperature, moisture, and aboveground litterfall in seasonal rainforest and limestone rainforest in Xishuangbanna, Yunnan. Results showed that soil microbial biomass carbon was higher in the rainy season than in the dry season in both forests, and there were significant seasonal dynamics in the limestone rainforest. In both seasons, the soil microbial biomass carbon was higher in limestone rainforest than in seasonal rainforest. Changes in soil microbial biomass carbon did not correlate with fluctuation of soil temperature, moisture or aboveground litterfall input in the same month, but there was a synchronized fluctuation between plant litter fail and soil microbial biomass carbon and from the previous two months. Our results suggest that fluctuation in soil microbial biomass carbon was driven by forest litter fall phenology. The peak of microbial biomass occurs two months behind the peak for plant litter fall. The reasons why soil microbial biomass carbon was higher in limestone rainforest than in seasonal rainforest may be higher organic carbon, nitrogen and pH value, and lower C/N of dominant leaf litter in Limestone rainforest. Further studies are necessary to clearly determine the mechanisms which drive microbial biomass carbon pool size.

关 键 词：土壤微生物生物量碳 季节动态 环境因子 热带雨林 

分 类 号：S154.3[农业科学—土壤学]