荒漠生态系统土壤表层微生物量碳空间分布及其影响因子  

Spatial Patterns of Soil Microbial Biomass Carbon and Factors Influencing the Distribution in a Typical Desert Ecosystem

作　　者：管海英[1,2] 赵鑫[1] 靳佳[1,2] 张思楠[1,2] 徐璐[1,2] 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]中国科学院大学,北京100049

出　　处：《干旱区研究》2014年第6期1125-1131,共7页Arid Zone Research

基　　金：国家基金委青年基金项目(41101249);国家重大科学研究计划(2012CB956204)

摘　　要：土壤微生物作为荒漠生态系统中的重要分解者,对干旱区碳循环有着重要作用。以干旱区荒漠生态系统柽柳保护样地为对象,利用统计学与地统计学中的空间自相关方法,分析在自然状况下土壤微生物量碳及其影响因子之间的空间变异和响应特征,探讨柽柳荒漠生态系统的土壤微生物量空间分布特征及其控制机理。结果表明：土壤微生物量碳为14.1～1 178.6μg·g-1,远小于其他生态系统;空间分布表现出植被覆盖越密集,土壤微生物量碳越大,且全局空间分布为正相关趋势,局部空间自相关指数Moran’s I为-0.2～0.5;土壤微生物量碳与土壤环境因子中的土壤水分（W）、土壤温度（T）均呈显著正相关（P〈0.05）,且空间相关系数分别为0.56和0.64。这些结果说明荒漠生态系统中土壤微生物量碳表现出强烈的空间异质性,且空间分布在10 m格网尺度（像元尺度）与植被覆盖度、温湿度显著相关,这些将有助于加强对干旱区土壤碳库空间格局的理解,从而制定更精细的土壤微生物量碳空间自相关的像元尺度。Soil microbes, as main decomposers in desert ecosystems, play an important role in the carbon （C） cycle in arid lands. Using the geostatistical spatial autocorrelation method, this study explored the spatial distribu- tion patterns of the surface soil microbial biomass carbon in a selected Tamarix chinensis desert ecosystem, a typical desert ecosystem and further analyzed the environmental factors affected the distribution. The results showed that the microbial biomass C varied from 14.1 - 1 178.6 μg · g-l in the selected ecosystem, which was far more less than in the other ecosystem. The distribution presented as the higher the vegetation density, the larger the soil mi- crobial biomass C. The soil microbial biomass exhibited a positive global spatial autocorrelation with its environmen- tal factors and the local spatial autocorrelation Moran＇s I indexes varied from -0.2 to 0.5. The soil microbial bio- mass had a positive and significant relationship （ P 〈 0.05 ） with soil moisture and soil temperature, with spatial correlation coefficients of 0.56 and 0.64, respectively. The results suggested that soil microbes in the desert eco- system scale shows strong spatial heterogeneity and its distribution at 10 m level was heavily affected by vegetation density, soil moisture and soil temperature. This study would be in help to improve the understanding of the spatial distribution of soil carbon in arid lands and to define a finer spatial autocorrelation pixel scale accordingly.

关 键 词：荒漠生态系统 土壤微生物量碳 空间分布 柽柳 地统计学 

分 类 号：S154.3[农业科学—土壤学]