黄土丘陵区长芒草群落对土壤水分入渗的影响  

Effect of Stipa bungeana Communities on Soil Infiltration in Soil Profile in Loess Hilly Region

作　　者：王国梁[1,2] 刘国彬[2] 

机构地区：[1]西北农林科技大学水土保持研究所,陕西杨陵712100 [2]中国科学院水利部水土保持研究所,陕西杨陵712100

出　　处：《水土保持学报》2009年第3期227-231,共5页Journal of Soil and Water Conservation

基　　金：中国科学院"西部之光"人才资助项目;国家"十一五"科技支撑项目(2006BAD09B03)

摘　　要：以黄土丘陵区长芒草群落为研究对象,采用圆盘入渗仪对不同盖度长芒草群落下的土壤入渗过程进行了对比研究。结果表明,在0-80 cm土壤剖面上,不同盖度的长芒草群落下土壤初始入渗速率和稳定入渗速率都随着土壤深度增加而下降。在同一深度的土壤剖面上,群落盖度越大土壤初始入渗速率和稳定入渗速率也分别越高。影响土壤初始入渗速率的主要因素是土壤有效孔隙度、初始含水量和水稳性团聚体含量。影响土壤稳定入渗速率的主要因素是土壤有效孔隙度、根长密度和水稳性团体含量,但水稳性团聚体对表层土壤初始入渗速率和稳定入渗速率的影响不显著。长芒草群落不仅通过根系对土壤的物理机械作用以及根系周转过程中形成的生物性大孔提高了土壤入渗速率,还通过提高土壤有机质和水稳性团聚体含量提高了土壤入渗速率。Stipa bungeana communities with different coverages were selected to measure the effect of the plant communities on soil infiltration process using disc permeameter in Loess hilly region. The results showed both the initial infiltration rates （IIRs） and stable infiltration rates （SIRs） in S. bungeana communities decreased with soil depths in 0--80 cm soil profile. Additionally, the IIRs and SIRs increased with the increasing of community coverages. The stepwise regression analysis showed the main factors influencing the IIRs were effective porosity, initial soil moisture and water-stable aggregate, while the main factors influencing the SIRs were effective porosity, root length density and water-stable aggregate. However, the waterstable aggregates had no significant influence on IIR and SIR in surface soil. S. bungeana communities could increase soil infiltration rates because the plant roots not only can increase the soil cranny by physical function and the biological pore by root turnover, but also can improve the soil organic matter contents and water-stable aggregate contents.

关 键 词：长芒草群落 入渗速率 入渗过程 植物根系 土壤剖面 

分 类 号：S157[农业科学—土壤学]