灌草镶嵌坡面土壤紧实度变异及水文连通度的影响  

Variation of Soil Compaction and the Impacts of Hydrological Connectivity on Shrub-Grass Mosaic Slope

作　　者：徐莉 刘宇[1,3] 张忠启 赵亮 蒋军乐 XU Li;LIU Yu;ZHANG Zhongqi;ZHAO Liang;JIANG Junle(School of Geography,Geomatics and Planning,Jiangsu Normal University,Xuzhou,Jiangsu 221116,China;Key Laboratory of Ecosystem Network Observation and Modelling,Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Information Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China)

机构地区：[1]江苏师范大学地理测绘与城乡规划学院,江苏徐州221116 [2]中国科学院地理科学与资源研究所,生态系统网络观测与模拟重点实验室,北京100101 [3]中国科学院大学,北京100049 [4]河北科技大学,石家庄050018

出　　处：《水土保持研究》2020年第5期133-137,146,共6页Research of Soil and Water Conservation

基　　金：国家自然科学基金面上项目(41671186);中国科学院大科学培育专项项目(121311KYSB20170004)。

摘　　要：在半干旱区,灌草镶嵌的植被分布通过改变水文连通度和使牲畜移动路径更为集中,从而可能改变土壤紧实度的坡面格局。为探究灌草镶嵌坡面土壤紧实度的空间变异及水文连通度的影响,在芦河流域选择典型坡面开展调查。沿坡面布设93个样点测定土壤紧实度,探究灌丛—草地镶嵌的坡面土壤紧实度沿坡面的变化。同时以水文连通度为灌草镶嵌格局的表征,阐释土壤紧实度与水文连通度的关系。结果表明:灌丛下和灌丛间草地土壤紧实度沿坡顶至坡底方向均呈现先增加后减小的趋势,即坡中部位置土壤紧实度最高;同一坡位,灌丛下土壤紧实度低于灌丛间草地土壤紧实度;灌丛土壤紧实度随累积汇流面积的增加而减小,而草地土壤紧实度随累积汇流面积的增加而增加。灌丛、草地斑块拦截上坡来沙能力的差别和牲畜移动路径在灌丛间草地更集中是导致这种空间分异的重要原因。In semi-arid areas,the vegetation distribution inlaid with grass and shrubs will significantly change this pattern.Hydrological connectivity is an effective indicator for erosion risk.Therefore,the hydrological connectivity concept is used to characterize the shrub-grass mosaic hillslope.And then the response of the soil compaction on the hillslope to the hydrological connectivity was explored.A hillslope with shrub-grass mosaic,which is typical in the Luhe River Basin,was selected as study site to investigate the impact of vegetation pattern and hydrological connectivity on the variation of soil compaction.Soil compactness of 93 points for shrub and grass patches respectively was surveyed on the hillslope.The results showed that at the same slope position,soil compactness of shrub patches was lower than that of grassland patches,the maximum difference of soil compactness between shrub patches and grass pattches was 23.66 kg/cm^2,and the minimum difference was 1.49 kg/cm^2;the soil compactness of shrub and grassland increased first and then decreased from the upslope to the foot of the slope;the soil compactness of shrub soil decreased with the increase of flow accumulation,while soil compactness of grassland increased with the increase of flow accumulation.Difference in capacity of sediment retention and regulation of livestock movement routes are important causes for the spatial variation of soil compactness,as well the soil compactness difference between shrub patches and grass patches.

关 键 词：景观连通度 灌丛—草地镶嵌景观 土壤侵蚀 土壤紧实度 半干旱区 

分 类 号：S152[农业科学—土壤学] K903[农业科学—农业基础科学]