生物结皮发育对毛乌素沙地土壤粒度特征的影响  

Effects of Biological Soil Crusts on Soil Particle Size Characteristics in Mu Us Sandland

作　　者：高广磊[1] 丁国栋[1] 赵媛媛[1] 冯薇[1] 包岩峰[1] 刘紫葳[2] 

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]渥太华大学地理系

出　　处：《农业机械学报》2014年第1期115-120,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家重点基础研究发展计划(973计划)资助项目(2013CB429906);国家林业局公益性行业科研专项经费资助项目(201304325);'十二五'国家科技支撑计划资助项目(2012BAD16B02)

摘　　要：以宁夏盐池荒漠生态系统定位研究站域内藻、地衣、苔藓3种不同发育阶段生物结皮及裸沙地为研究对象，应用激光衍射粒度分析技术测定土壤粒度组成，计算分析平均粒径、标准偏差、偏度、峰态值和分形维数等土壤粒度特征参数，研究结果显示：研究区土壤粒度组成以砂粒为主，约占土壤颗粒体积分数的80％～95％，而粘粒、粉粒含量较少；土壤粒度分布较为集中，分选状况较差，偏度状况为极正偏度，峰态值为很尖窄、尖窄；土壤分形维数分布于2．15～2．30之间，且从大到小依次为苔藓结皮、地衣结皮、藻结皮、裸沙地。在生物结皮发育过程中，土壤粘粒、粉粒等细粒物质不断增加；粒度组成不断优化，整体呈现向均匀和对称分布演化趋势。生物结皮能够有效改良土壤结构，促进土壤发育，但速度十分缓慢。To reveal the effects of biological soil crusts （BSCs） on soil particle size characteristics in Mu Us Sandland, soil samples under algae, lichens, and mosses crusts as well as the uncovered sandlar were selected in Yanchi research station. Soil particle size distributions were identified by using las diffraction technique. Particle size parameters were subsequently calculated including average partic size, standard deviation, skewness, kurtosis and fractal dimension. The results indicate that the majori soil particle size is occupied by sand particles approximately accounting for 80% -95% of the tot volume; accordingly clay and silt particles contents are much less; soil particle size distributions different sites are comparatively centralized that resulted in poor sorting, very positive skewness as well sharp or very sharp kurtosis; the fractal dimension of soil increases progressively across the successior stages of BSCs in range of 2.15 - 2. 30. In short, as affected by BSCs, clay and silt particles continue increase leading to constantly particle distribution optimization, and soil particle size distribution inclin~ to uniform and symmetric pattern. Therefore, BSCs are beneficial to soil improvement and developmen but rather slowly.

关 键 词：土壤粒度 毛乌素沙地粒度参数 生物结皮 

分 类 号：P588.21[天文地球—岩石学] X141[天文地球—地质学]