江西红壤缓坡地壤中流影响因素分析

针对地表植被覆盖、死地被物敷盖、裸地3种类型的坡面,采用径流小区试验方法,研究江西红壤表层(距地表30 cm)、底层(距地表60 cm)壤中流及地下径流(距地表105 cm)特征,运用数理统计方法分析壤中流流量、流速、历时与降雨、径流因子的相关关系。结果表明:1.与裸地相比,百喜草覆盖、死地被物敷盖显著增加壤中流量,2种措施都延长壤中流历时;2.壤中流量与雨量、雨强、降雨历时、初渗雨量呈正相关关系,覆盖、敷盖小区壤中流量受雨量影响较大,而裸地小区壤中流量受雨强影响较大;3.表层壤中流历时与降雨因子有较好相关性,而底层壤中流历时与降雨因子相关性很差;降雨历时对壤中流历时影响最大,降雨量影响最小;4.壤中流流速与因子的关系受措施及土层深影响,在植被覆盖、死地被物敷盖小区表层与雨量相关性最好,在裸地表层与雨强相关性最好。在各小区底层流速均与降雨历时相关性最好;5.裸地地表径流量与壤中流量相关关系不显著,在采取2种措施后,地表径流量与壤中流量呈线性正相关关系。随地表径流量的增大,覆盖措施壤中流量增大幅度大于敷盖措施。

Factors Affecting Interflow of Gentle Hill in Jiangxi Province

Observed on bare slope,litter covered slope,vegetation covered slope at plots in Jiangxi province,the relationship between interflow's runoff,velocity,duration and precipitation and runoff factors was analysed by mathematical statistics methods.The result shows that: 1.Interflow in well covered slope is apparently larger than that of bare slope,and the former prolongs the the interflow duration;2.The interflow is positively related to rainfall,rainfall density,rainfall duration,mainly affected by precipitation at covered slope,and mainly affected by rainfall velocity at bare slpoe;3.The interflow duration is apparently related to rainfall factors on the surface level,and unapparently related in the bottom.The interflow duration is mostly affected by rainfall duration,and precipitation does least;4.The relationship between interflow velocity and factors affected by measures and the depth of soil,and the main affected factors shows same regularities.5.Interflow was unaparently related to the surface runoff at bare slope,and postitively related at covered slope,the increase amount at vegetation slope is larger than that of litter covered slope.