地表覆盖对紫色土坡耕地壤中流流动和硝态氮运移过程的影响
|
摘要
针对不同坡度下的表土结皮和稻草覆盖两种地表状况下的紫色土坡耕地,构建养分淋失的三维对流—弥散模型,数值模拟坡耕地中水分和硝态氮浓度的时空分布,研究不同地表覆盖对紫色土坡耕地壤中流流动和硝态氮运移过程的影响。结果表明:表土结皮通过减少水分入渗使壤中流流量与稳定强度降低,硝态氮随壤中流流失量减少,而稻草覆盖下的情况正好相反;在降雨强度为30mm/h、降雨历时为3h,坡度分别为5°,10°,15°,20°和25°的情况下,结皮使壤中流流量降低34.8%～43.0%,硝态氮随壤中流流失量减少8.6%～34.4%,而稻草覆盖下壤中流出流量增加8.6%～12.6%,硝态氮随壤中流流失量增加8.6%～15.4%。对于紫色土坡耕地,在采用稻草覆盖增加入渗的情况下,应采取相应的措施保水保肥。
For two kinds of surface conditions of sloping farmland of purple soil with topsoil crust and straw mulching under different slope gradients,the three-dimensional convective-dispersion model of nutrient leaching was established,the temporal and spatial distributions of interflow and nitrate concentration had been simulated numerically,and influences of surface mulching on interflow and nitrate migration process were studied.The results showed that,for topsoil crust,the rate and steady strength of interflow as well as the nitrate loss in the soil decreased due to reduction of water infiltration,while the situation for the straw mulch was opposite.For three hours rainfall with intensity of 30 mm/h,when slope gradients are 5°,10°,15°,20°and 25°,respectively,for topsoil crust,the rate at outlet decreased by 34.8%～43.0%,and the nitrate loss in the soil decreased by 8.6%～34.4%.However,for the straw mulch,the rate increased by 8.6%～12.6%,and the nitrate loss increased by 8.6%～15.4%.For the purple soil slope farmland,the appropriate measures should be taken to keep the water and fertilizer under the conditions of using straw mulch to increase infiltration.
For two kinds of surface conditions of sloping farmland of purple soil with topsoil crust and straw mulching under different slope gradients,the three-dimensional convective-dispersion model of nutrient leaching was established,the temporal and spatial distributions of interflow and nitrate concentration had been simulated numerically,and influences of surface mulching on interflow and nitrate migration process were studied.The results showed that,for topsoil crust,the rate and steady strength of interflow as well as the nitrate loss in the soil decreased due to reduction of water infiltration,while the situation for the straw mulch was opposite.For three hours rainfall with intensity of 30 mm/h,when slope gradients are 5°,10°,15°,20°and 25°,respectively,for topsoil crust,the rate at outlet decreased by 34.8%～43.0%,and the nitrate loss in the soil decreased by 8.6%～34.4%.However,for the straw mulch,the rate increased by 8.6%～12.6%,and the nitrate loss increased by 8.6%～15.4%.For the purple soil slope farmland,the appropriate measures should be taken to keep the water and fertilizer under the conditions of using straw mulch to increase infiltration.
引文
[1]廖晓勇,陈治谏,刘卲权,等.三峡库区紫色土坡耕地不同利用方式的水土流失特征[J].水土保持研究,2005,12(1):159-161.
[2]Skujins J.Semiarid lands and deserts:soil resource and reclamation[J].Semiarid Lands&Deserts Soil Resource&Reclamation,1991.
[3]Lehrsch,Gary A,Kincaid,et al.Sprinkler droplet energy effects on soil penetration resistance and aggregate stability and size distribution[J].Soil Science,2006,273(1/2):1-13.
[4]Cai Q,Luk S H.Experimental Study of Surface Crusts Process and Microfabric Analysis on Loess Soil[J].Journal of Basicence&Engineering,1996,4:363-370.
[5]Bu C,Cai Q C Q,Wu S F.Development of soil crust on the surface of purplish soil[J].Acta Pedologica Sinica,2007,44(3):385-391.
[6]程琴娟,蔡强国,马文军.我国水土流失典型区土壤土结皮敏感性[J].地理研究,2008,27(6):1290-1298.
[7]卜崇峰,蔡强国,程琴娟,等.紫色土表土结皮发育特征的试验研究[J].土壤学报,2007,44(3):385-391.
[8]付智勇,李朝霞,蔡崇法,等.不同起始条件下坡面薄层紫色土水分和壤中流响应[J].水利学报,2011,42(8):899-907.
[9]蔡崇法,丁树文,张光远,等.三峡库区色土坡地养分状况及养分流失[J].地理研究.1996,15(3):77-84.
[10]徐勤学,王天巍,李朝霞,等.紫色土坡地壤中流特征[J].水科学进展,2010,21(2):229-234.
[11]Chahinian N,Voltz M,Trotoux G,et al.Assessing the impact of a soil surface crust on simulated overland flow at the field scale.EGS-AGU-EUG Joint Assembly,2003.
[12]Chahinian Nanée,Voltz Marc,Moussa Roger,et al.Assessing the impact of the hydraulic properties of a crusted soil on overland flow modelling at the field scale[J].Hydrological Processes,2006,20(8):1701-1722.
[13]虎胆·吐马尔白,苏里坦.反演分析土壤-秸秆水分运动参数[J].灌溉排水学报,2009,28(1):68-70.
[14]吴元芝,黄明斌.基于Hydrus-1D模型的玉米根系吸水影响因素分析[J].农业工程学报,2011,27(S2):66-73.
[15]李玮,何江涛,刘丽雅,等.Hydrus-1D软件在地下水污染风险评价中的应用[J].中国环境科学,2013,33(4):639-647.
[16]张虹.红壤地表结皮特征及其对导水性能的影响[D].武汉:华中农业大学,2012.
[17]龙天渝,刘祥章,刘佳.紫色土坡耕地硝态氮随壤中流迁移的时空分布模拟[J].农业环境科学学报,2015,34(10):1973-1978.
[18]郑海金,王辉文,杨洁,等.地表径流和壤中流对坡耕地氮磷流失影响研究概述[J].中国水土保持,2015(2):36-39.
[2]Skujins J.Semiarid lands and deserts:soil resource and reclamation[J].Semiarid Lands&Deserts Soil Resource&Reclamation,1991.
[3]Lehrsch,Gary A,Kincaid,et al.Sprinkler droplet energy effects on soil penetration resistance and aggregate stability and size distribution[J].Soil Science,2006,273(1/2):1-13.
[4]Cai Q,Luk S H.Experimental Study of Surface Crusts Process and Microfabric Analysis on Loess Soil[J].Journal of Basicence&Engineering,1996,4:363-370.
[5]Bu C,Cai Q C Q,Wu S F.Development of soil crust on the surface of purplish soil[J].Acta Pedologica Sinica,2007,44(3):385-391.
[6]程琴娟,蔡强国,马文军.我国水土流失典型区土壤土结皮敏感性[J].地理研究,2008,27(6):1290-1298.
[7]卜崇峰,蔡强国,程琴娟,等.紫色土表土结皮发育特征的试验研究[J].土壤学报,2007,44(3):385-391.
[8]付智勇,李朝霞,蔡崇法,等.不同起始条件下坡面薄层紫色土水分和壤中流响应[J].水利学报,2011,42(8):899-907.
[9]蔡崇法,丁树文,张光远,等.三峡库区色土坡地养分状况及养分流失[J].地理研究.1996,15(3):77-84.
[10]徐勤学,王天巍,李朝霞,等.紫色土坡地壤中流特征[J].水科学进展,2010,21(2):229-234.
[11]Chahinian N,Voltz M,Trotoux G,et al.Assessing the impact of a soil surface crust on simulated overland flow at the field scale.EGS-AGU-EUG Joint Assembly,2003.
[12]Chahinian Nanée,Voltz Marc,Moussa Roger,et al.Assessing the impact of the hydraulic properties of a crusted soil on overland flow modelling at the field scale[J].Hydrological Processes,2006,20(8):1701-1722.
[13]虎胆·吐马尔白,苏里坦.反演分析土壤-秸秆水分运动参数[J].灌溉排水学报,2009,28(1):68-70.
[14]吴元芝,黄明斌.基于Hydrus-1D模型的玉米根系吸水影响因素分析[J].农业工程学报,2011,27(S2):66-73.
[15]李玮,何江涛,刘丽雅,等.Hydrus-1D软件在地下水污染风险评价中的应用[J].中国环境科学,2013,33(4):639-647.
[16]张虹.红壤地表结皮特征及其对导水性能的影响[D].武汉:华中农业大学,2012.
[17]龙天渝,刘祥章,刘佳.紫色土坡耕地硝态氮随壤中流迁移的时空分布模拟[J].农业环境科学学报,2015,34(10):1973-1978.
[18]郑海金,王辉文,杨洁,等.地表径流和壤中流对坡耕地氮磷流失影响研究概述[J].中国水土保持,2015(2):36-39.