黄土高塬沟壑区退耕地土壤抗冲性及其与影响因素的关系  

Soil anti-scouribility of abandoned land and its relationship with influencing factors in Loess Plateau Gully region

作　　者：郭明明[1] 王文龙[1,2] 史倩华 陈同德[1] 李建明[3] 康宏亮[1] 朱宝才[1,4] 李艳富[5] 

机构地区：[1]西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,杨凌712100 [2]中国科学院水利部水土保持研究所,杨凌712100 [3]长江科学院水土保持研究所,武汉430010 [4]山西农业大学林学院,太谷030801 [5]南京水利科学研究院,南京210029

出　　处：《农业工程学报》2016年第10期129-136,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金(41571275;41302199);中国科学院西部行动计划(KZCX-XB3-13);中国科学院知识创新工程重大项目(KZZDEW-04-03)

摘　　要：为了评价退耕地土壤抗冲性的变化,该文以黄土高塬沟壑区自然退耕农地为研究对象,通过径流小区冲刷法对不同覆盖度塬面退耕地（TAL,table-land abandoned land）和沟头退耕地（GAL,gully-head abandoned land）土壤抗冲性进行了研究。结果表明,1）与对照（Ⅰ）相比,TAL和GAL处理水稳性团聚体、根系密度和根系生物量均显著增加（P〈0.05）,覆盖度大于0时,崩解速率显著减小44.87%-79.16%和33.79%-70.65%,有机质显著增加70.12%-222.70%和59.20%-194.88%,覆盖度最大时,土壤容重和渗透系数才显著减小和增大。2）TAL处理0覆盖度小区抗冲系数（AS,anti-scouribility）较对照无差异,其余覆盖度则显著增大2.31-7.57倍,GAL处理AS较对照显著增大0.99-7.12倍,覆盖度越大,根系提高土壤抗冲性能的效果越显著。3）TAL和GAL处理AS分别与容重、崩解速率、水稳性团聚体含量、渗透系数均呈极显著指数函数关系,与有机质含量、根系生物量及根系密度均呈极显著线性函数关系。水稳性团聚体是影响塬面和沟头退耕地土壤抗冲性的关键因子。结果可为研究区退耕还林还草工程生态功能评价及水土流失治理提供理论依据。Ecological environment of the Loess Plateau has been remarkably improved and soil and water loss is effectively controlled due to the implementation of the ＂grain for green＂project. The most crucial reason is that the physical consolidation, reticular connection, root-soil agglomeration and biochemical reaction effects make the soil anti-scouribility（AS） to be improved significantly. In order to evaluate the impacts of abandoned land and their different coverage levels on soil AS and related soil physical properties, twenty plots with two treatments of table-land abandoned land（TAL） and gullyhead abandoned land（GAL）, five abandoned plant coverage levels and two repeated experiments were selected to study the soil AS by using runoff plot flow-scouring method in the gully area of the Loess Plateau. The soil AS was determined in 2 m×0.5 m runoff plot at an adjusted discharge of 4 L/min for 31 minutes. Within 31 minutes of each test, runoff and sediment samples were collected every one minute in the first three minutes and every two minutes in the following testing time using runoff bucket for determining sediment concentration. Soil bulk density, water-stable aggregate content, soil disintegration rate, infiltration rate and organic matter content were determined by using conventional methods. Root density and biomass were determined by harvesting and dried in oven. The results showed that as the coverage of the abandoned land increased,compared with CK（farmland）, water-stable aggregate content, root density and root biomass of TAL and GAL measurements were significantly increased（P〈0.05）. When coverage was more than 0%, soil disintegration rate of TAL and GAL measurements had a decrease of 44.87% -79.16% and 33.79% -70.65%, respectively. While the increments of 70.12% -222.70% and 59.20%-194.88% for organic matter content. When coverage was the most highest, the soil bulk density was decreased and infiltration coefficient was increased significantly, for TAL and GAL respectively. The AS o

关 键 词：土壤 土地利用 植被 理化性质 退耕地 根系 土壤抗冲性 黄土高塬沟壑区 

分 类 号：S157.1[农业科学—土壤学]