不同地表状况、降雨强度与坡度对径流水中K、Na、Ca、Mg流失量的影响  

Effects of Different Surface Conditions, Rainfall Intensities and Slopes on K, Na, Ca, Mg Losses in Runoff

作　　者：华珞[1] 李俊波[1] 蔡典雄[2] 冯琰[1] 朱凤云[1] 马礼[1] 周万荣[2] 

机构地区：[1]首都师范大学资源环境与地理信息系统北京市重点实验室,北京100037 [2]中国农业科学院土壤肥料研究所,北京100081

出　　处：《水土保持学报》2004年第6期11-15,20,共6页Journal of Soil and Water Conservation

基　　金：北京市自然科学基金项目(6012004);国家重大项目"863"专题(2002AA6Z3021);首都师范大学资源环境与地理信息系统北京市重点实验室项目

摘　　要：采用室内模拟降雨装置,对供试的密云县农田褐土分别进行了在3种不同地表状况(裸地、草皮覆被、秸秆覆盖),3种降雨强度(60mm/h,90mm/h,120mm/h),5种坡度(10°,15°,20°,25°,30°)下的交叉实验,对不同降雨时间段下表层径流水中K、Na、Ca、Mg流失量进行测试分析,结果表明:在坡度10°,15°的3种降雨强度下,各阳离子流失量在相同时间段内总体表现为秸秆覆盖<草皮覆被<裸地,在坡度20°,25°,30°时草皮覆被对各阳离子流失量的抑制效果明显;相同地表、坡度和降雨时间段,K、Na、Ca、Mg流失量均表现出60mm/h<90mm/h<120mm/h,Mg规律性最强;相同雨强和降雨时段下,草皮覆被和秸秆覆盖地表下Na、Ca、Mg流失量随着坡度的增加呈递增态势;随着时间段的增加各阳离子流失量总体呈递增态势,只有在雨强90mm/h时部分元素有所差异;相同雨强1h时段内不同阳离子流失总量之间随坡度的变化存在相关性。The cross-experimentations that aimed at farmland cinnamon soil of Miyun county was done by the simulated rainfall equipment under three different surface conditions (bare land, turf mulching, straw mulching), three kinds of rainfall intensities (60 mm/h, 90 mm/h, 120 mm/h) and five slopes(10°,15°,20°,25°,30°). The K, Na, Ca, Mg losses of runoff in different rainfall durations were tested and analyzed by this experimentation,the results showed that: in the same rainfall duration, the cations losses expressed that straw mulching<turf mulching<bare land under three rainfall intensities of 10° and 15° slopes. And the turf mulching dramatically restrained the cations losses of runoff under the slopes of 20°,25°,30°. When it was same surface conditions, same slope and same rainfall duration, the K, Na, Ca, Mg cations losses were 60 mm/h<90 mm/h<120 mm/h. The law of Mg was stronger especially. Under the same rainfall intensity and the same rainfall duration, Na, Ca, Mg losses of turf and straw mulching went up with the slopes raised. Each cation losses was raised with the durations increasing, and only under the 90 mm/h rainfall intensity, some cations losses were different. There were relativities in amounts of different cations losses with the change of slopes under the same rainfall intensity in an hour.

关 键 词：地表状况 降雨强度 坡度 径流水 K NA CA Mg 流失量 

分 类 号：S157.1[农业科学—土壤学]