黄土高原丘陵区典型植物群落土壤粒径分布特征  

Characteristics of soil particle size distribution of typical plant communities on the hilly areas of Loess Plateau

作　　者：沙国良 魏天兴[1,2,3] 陈宇轩 傅彦超[1,2,3] 任康 SHA Guoliang;WEI Tianxing;CHEN Yuxuan;FU Yanchao;REN Kang(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;Key Laboratory of State Forestry Administration on Soil and Water Conservation and Desertification Combating,Beijing Forestry University,Beijing 100083,China;Jixian National Forest Ecosystem Observation and Research Station,CNERN/CFERN,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]北京林业大学水土保持与荒漠化防治国家林业局重点实验室,北京100083 [3]山西吉县森林生态系统国家野外科学观测研究站,北京100083

出　　处：《干旱区地理》2022年第4期1224-1234,共11页Arid Land Geography

基　　金：国家生态系统观测研究网络运行服务项目(2019-2020);“十三五”国家重点研发计划项目课题(2016YFC0501705)资助。

摘　　要：为探究黄土高原丘陵区不同植物群落的土壤粒径分布特征。选取草地、山杏纯林、油松纯林和油松山杏混交林0~200 cm土壤为研究对象,采用激光衍射技术测定土壤样品粒度组成,计算土壤粒度参数与分形维数,绘制粒度频率曲线。结果表明:(1)研究区土壤属粉壤土,粉粒含量约占总体的56.58%~71.67%,砂粒约占21.37%~38.71%,黏粒约占3.55%~6.96%。(2)各植物群落内土壤粒度组成随土层深度增加分布较为均一,粒径分布整体分选性均较差,呈极正偏度,峰态尖窄,粒度频率曲线为双峰型,曲线波峰一致。不同植物群落土壤粒径分布差异主要集中在土壤表层0~20 cm(P<0.05)。(3)草地、山杏纯林、油松纯林和油松山杏混交林0~200 cm土壤平均分形维数分别为2.63、2.60、2.61、2.58。分形维数与黏粒含量具有极显著正相关关系(P<0.05),其中,草地土壤分形维数与黏粒的相关性最强。总体来看,黄土高原丘陵区草地土壤粒径分布特征显著优于人工林,本研究结果可为黄土高原的生态重建工作提供理论依据。Soil particle size distribution(PSD),a basic soil physical property,is highly related to soil structure,water movement,fertility development,porosity condition,and soil-forming process and has been widely studied as an indicator of soil erosion in different plant communities.Generally,soil PSD comprises different layers of clay,silt,and sand.Among these layers,clay has the colloidal property that can effectively promote the formation and development of soil aggregates,enhance the stability of soil structure,and strengthen soil erosion resistance.Previous studies on the Loess Plateau of China only focused on the soil PSD in the upper soil layers,but the vertical variation in soil PSD in the deep layers is unknown.Additionally,planting large areas of pure forests leads to problems such as a single stand structure,weak stability of the intraforest ecosystem,poor resistance to disturbance,and restricted soil quality,all of which affect the sustainability of vegetation restoration.In the present work,soil samples(0-200 cm)from grassland,Pinus tabuliformis pure forests,Armeniaca sibirica pure forests,Pinus tabuliformis and Armeniaca sibirica mixed plantations were collected to examine the effects of different forest allocations on the vertical variation in soil PSD and provide a theoretical basis for the ecological reconstruction efforts work on the Loess Plateau.First,soil PSD was measured through laser diffraction technique.Then,soil particle size parameters(mean particle size,median particle size,standard deviation,and skewness and kurtosis values)and frequency distribution curve were calculated and analyzed.Finally,the fractal theory was applied to accurately express the soil structural form and function.Results showed that(1)the soils in the study area belonged to silty loam.The soil PSD of different plant communities was dominated by silt accounting for 56.58%-71.67%followed by sand accounting for 21.37%-38.71%and clay accounting for 3.55%-6.96%.(2)The soil PSD of different plant communities,which were primarily

关 键 词：人工林 土壤粒径分布 粒度参数 分形维数 黄土高原 

分 类 号：S714.2[农业科学—林学]