不同岩性区耕犁扰动对坡耕地土壤可蚀性的影响——以黔中地区为例  

Effects of tillage disturbance on soil erodibility in slope farmland of different lithology regions:A case study of central Guizhou

作　　者：杨懿 高华端[1] 李晓松 王群 罗爽 YANG Yi;GAO Huaduan;LI Xiaosong;WANG Qun;LUO Shuang(College of Forestry, Guizhou University, 550025, Guiyang, China)

机构地区：[1]贵州大学林学院,贵阳550025

出　　处：《中国水土保持科学》2022年第1期99-106,共8页Science of Soil and Water Conservation

基　　金：国家自然科学基金“喀斯特坡耕地浅层孔(裂)隙水文过程及土壤侵蚀过程响应机制”(41671275)。

摘　　要：为研究不同岩性发育形成的坡耕地土壤在耕犁扰动下的土壤可蚀性变化,为区域水土流失防治和生态环境建设提供参考,选取由紫色砂岩、砂页岩和石灰岩3种岩性发育形成的坡耕地为研究对象,采集耕犁层和犁底层土壤,测定土壤颗粒组成和有机质质量分数,利用EPIC模型,计算土壤可蚀性K值,根据K值变化分析不同岩性区坡耕地受耕犁扰动的影响。结果表明:紫色砂岩和砂页岩区土壤以黏壤和壤土为主,石灰岩区土壤以粉黏土、黏土和粉黏壤为主,3个岩性区土壤有机质质量分数大小依次表现为:石灰岩>砂页岩>紫色砂岩;紫色砂岩区的耕犁层和犁底层土壤在各粒级组成方面无显著差异,石灰岩区也无显著差异,砂页岩区犁底层土壤黏粒比例显著高于耕犁层,3个岩性区均表现出耕犁层有机质质量分数显著高于犁底层;研究区坡耕地土壤可蚀性因子K值介于0.041~0.059之间,耕犁层由大到小依次表现为:砂页岩>紫色砂岩>石灰岩,犁底层由大到小依次表现为:紫色砂岩>砂页岩>石灰岩;研究区8种土壤质地中,粉壤最易被侵蚀,黏土可蚀性最小。[Background]Soil erosion has become a global ecological and environmental problem,which is seriously threatening the survival of human beings and the sustainable development of the land.As the main eroded land,the slope farmland has become the main source of river sediment.Guizhou province is one of the most representative provinces in the mountainous and hilly areas of Southwest China.The area of sloping farmland accounts for as much as 82.90%of the total farmland area.The soil erosion of the sloping farmland in this region cannot be underestimated.Therefore,it is of great significance to clarify the soil erosion characteristics of sloping farmland for the prevention and control of regional soil and water loss.[Methods]In this study,sloping farmland formed by purple sandstone,sand shale and limestone was selected as the research object.A total of 120 soil samples were collected from plough layer and plowpan.The soil particle composition was determined by the pipette method,and the organic matter content was determined by potassium dichromate heating method.Then the EPIC model was used to calculate the soil erodibility K value.According to the change of K value,the influence of tillage disturbance on slope farmland in different lithologic regions was analyzed.[Results]1)The soil in the purple sandstone and sand shale area is dominated by clay and loam,and the soil in the limestone area is dominated by silt clay,clay and silt clay loam.The organic matter content of the three lithological areas is shown in order of limestone>sand shale>purple sandstone.2)There is no significant difference in the composition of the plough layer and plowpan soil in the purple sandstone area and the limestone area.The clay content of the plough layer soil in the sand shale area is significantly higher than that of the plowpan.Three lithology areas show that the organic matter content of the plough layer is significantly higher than that of the plowpan soil.3)The K value of the slope farmland in the study area is between 0.041 and 0.05

关 键 词：岩性 坡耕地 土壤可蚀性 EPIC模型 

分 类 号：S157.1[农业科学—土壤学]