水文条件对紫色土坡面土壤侵蚀及养分流失的影响  

Effects of hydrological conditions on soil erosion and nutrient loss at purple soil hillslope

作　　者：崔艳平[1,2] 郑粉莉[1,2] 刘雨[1,2] 

机构地区：[1]西北农林科技大学资源环境学院 [2]中国科学院水利部水土保持研究所,黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100

出　　处：《中国水土保持科学》2009年第1期1-7,共7页Science of Soil and Water Conservation

基　　金：国家重点基础研究发展计划项目课题“不同类型区土壤侵蚀过程与机理”(2007CB407201);中国科学院西部行动计划(二期)课题“水文过程响应及其模拟”(KZCX2-XB2-05-03);西北农林科技大学创新团队建设计划项目“土壤侵蚀及其治理环境效应评价”(01140202)

摘　　要：采用人工模拟降雨试验,研究水文条件对紫色土坡面土壤侵蚀及氮和磷养分流失的影响。试验处理包括2个施肥水平（低肥和高肥水平）,4个水文条件（自由下渗、土壤水分饱和、壤中流、壤中流＋降雨）和一个降雨强度（60 mm/h,历时60 min）。结果表明：壤中流＋降雨和土壤水分饱和条件下的土壤侵蚀量分别是自由下渗条件下的3.1和1.7倍,同自由下渗相比,壤中流、壤中流＋降雨和土壤水分饱和条件下,地表径流中NO3-N、HPO4-P的浓度和流失量有显著增加;低肥水平条件下,自由下渗、土壤水分饱和、壤中流和壤中流＋降雨地表径流中,NO3-N的浓度分别是0.88、58.90、698.41和87.80 mg/L,对应水文条件下地表径流中,HPO4-P的浓度分别是0.252、0.322、0.811和0.383 mg/L,高肥水平条件下,径流中的NO3-N和HPO4-P的浓度也有相同的趋势;土壤水分饱和条件下,地表径流中NO3-N和HPO4-P的流失量分别是自由下渗条件下的27～39和1.3倍,壤中流＋降雨条件下,地表径流中NO3-N和HPO4-P的流失量分别是自由下渗条件下的100～114和1.5～1.7倍,同时,壤中流＋降雨和土壤水分饱和条件下,泥沙中NO3-N和HPO4-P的流失量也比自由下渗条件下显著增加。This paper quantitatively studied effects of hydrological conditions on soil erosion, nitrogen and phosphorus losses at purple soil hillslope by using of rainfall simulator. Experimental treatments included two levels of fertilizer input （low and high input ） and four near-surface soil hydrological conditions （free infiltration; water saturation; subsurface flow without rainfall; and subsurface flow with rainfall）. Rainfall intensity of 60 mm/h was simulated for 60 min. The results showed that soil loss of subsurface flow with rainfall and water saturation treatments is 3.1 and 1.7 times higher than that of free infiltration. The concentrations and losses of the NO3-N and HPO4-P in surface runoff of subsurface flow without rainfall, subsurface flow with rainfall, and water saturation are much higher than those of free infiltration. Under the low fertilizer input, the NO3-N concentrations in surface runoff from free infiltration, water saturation, subsurface flow without rainfall and subsurface flow with rainfall are 0.88, 58.90, 698.41, and 87.80 mg/L, respectively; HPO4-P concentrations from rainfall are 0.252, free infiltration, 0.322, 0.811 water saturation, subsurface flow without rainfall and subsurface flow with concentrations of NO3-N and HPO4-P and 0.383 mg/L, respectively. Similar trends are observed for the under the high fertilizer treatment . NO3-N and HPO4-P loadings from water saturation and subsurface flow with rainfall are 27 - 39 and 100 - 114 times higher than those from free infiltration ; and HPO4-P loadings from water saturation and subsurface flow with rainfall are 1.3 and 1.5 - 1.7 times higher than those from free infiltration. Meanwhile, the losses of the NO3-N and HPOa-P in sediment from subsurface flow with rainfall and water saturation are higher than those from free infiltration.

关 键 词：水文条件 紫色土 壤中流 土壤侵蚀 养分流失 

分 类 号：S157.1[农业科学—土壤学] TV147[农业科学—农业基础科学]