单 位：
北京林业大学水土保持学院国家林业局水土保持与荒漠化防治重点实验室
摘 要：
以重庆市四面山的林地(天然针阔叶混交林地、天然阔叶林地)、农田(玉米)为研究对象,利用染色示踪法,从染色图像中提取出5个优先流特征指标,揭示了四面山地区不同植被覆盖下土壤优先流特征,并采用主成分分析法探究土壤质地、化学性质和植物根长密度、根重密度等根系因子对优先流的影响。结果表明,3种植被覆盖下土壤染色区域均集中在0～10 cm表层范围内。其中,天然针阔叶混交林地达到63.44%,天然阔叶林地达到61.87%以上,农地达到43.56%。林地的优先流发育程度大于农地,具体表现为天然针阔叶混交林地>天然阔叶林地>农地。随着土层深度的增加,优先流表现出一定的空间异质性。土壤中砂粒含量的增加和粉粒含量的减少,增大了优先流发生的概率。优先流的形成过程中受土壤化学性质影响较大,随着土层深度的增加,3种样地的速效磷、全氮、有机质含量变化总体上均呈减少趋势。植物根系特征中的根重密度和根长密度(<1 mm、3～5 mm)是不同植被覆盖下对土壤优先流最主要的因素,二者与优先流的发育情况呈极显著正相关关系。
译 名：
Characteristics of soil preferential flow and its influencing factors under different vegetation cover
作 者：
CHENG Jingxuan;CHENG Jinhua;ZHENG Xin;ZHANG Yonggang;Key Laboratory of Soil and Water Conservation and Desertification Control of State Forestry Bureau,College of Soil and Water Conservation,Beijing Forestry University;
单 位：
CHENG Jingxuan%CHENG Jinhua%ZHENG Xin%ZHANG Yonggang%Key Laboratory of Soil and Water Conservation and Desertification Control of State Forestry Bureau,College of Soil and Water Conservation,Beijing Forestry University
关键词：
land use coverage;;preferential flow;;dye tracer
摘 要：
Woodlands of the Simian Mountains(natural coniferous and broad-leaved mixed forests,natural broad-leaved forest),farmland(maize) were selected as the research objects in Chongqing,using staining Tracer method to extract 5 preferential flow characteristics from the staining image,revealing the characteristics of soil preferential flow under different vegetation cover in the mountainous area,and the principal component analysis method was used to explore the soil texture,effects of root factors such as plant root length density and root density on preferential flow.The results showed that the three kinds of soil staining areas were concentrated in the 0～10 cm surface area.Among them,natural needle broad-leaved mixed forest reached 63.44%,natural broad-leaved forest reached more than 61.87%,and farmland reached 43.56%.The development of preferential flow of forest land was higher than that of the agricultural land,which is characterized by natural coniferous and broad-leaved mixed forest > natural broad-leaved forest land > farmland.With the increase of soil depth,the preferential flow shows some spatial heterogeneity.The increase of sand particle content and thedecrease of particle content in soil increases the probability of preferential flow.The formation of preferential flow was greatly affected by soil chemical properties.With the increase of soil depth,the change of available phosphorus,total nitrogen and organic matter content in three kinds of samples showed a decreasing trend in the process of the formation of preferential flow.Root density and root length density(<1 mm,3～5 mm) in plant root characteristics are the most important factors of soil preferential flow under different vegetation cover,and they have a very significant positive correlation with the development of preferential flow.
