农牧交错带土地利用类型对土壤风蚀的影响

Impacts of Land Use Type on Soil Wind Erosion in Agro-pastoral Area

[目的]研究农牧交错带不同土地利用类型对土壤风蚀的影响,为干旱沙区土地资源的合理利用及经营耕作提供科学依据。[方法]通过气象资料和野外风蚀试验,分析该区不同土地利用方式下的土壤风蚀状况。[结果]不同土地利用类型对土壤风蚀的影响显著,在不同利用类型的人工草地中羊草地较苜蓿地减蚀效果显著,天然草地中滨草地减蚀效果优于蒿草地,人工草地较天然草地显著降低土壤风蚀量。农田用地中耕翻地土壤风蚀量最高,未留茬免耕玉米地较耕翻地风蚀量减少46.7%~48.6%;作物留茬地土壤减蚀效果显著,且留茬作物不同,减蚀效果差异明显,玉米留茬较耕翻地风蚀量减少了58.1%~63.5%,荞麦留茬较耕翻地减蚀率为50.5%~54.6%。在不同地形坡地中迎风坡风蚀量高于背风坡3.12~3.73倍。[结论]应在该地区适宜增加人工草地种植面积,减少冬春季节耕翻地面积,减少迎风坡土地的开垦利用,在冬春季节采取地表覆盖或者作物收获后留茬的保护措施,以降低土壤风蚀程度。

[Objective] Impacts of land use type on soil erosion in agro-pastoral area were researched to provide a scientific basis for the rational use of land resources, including the farming and management in arid desert area.[Methods] Soil erosion status under different land use types were tested by field erosion experiments and analyzed by meteorological data.[Results] Land use type significantly affected soil erosion.For artificial grasslands, Leymus chinensis reduced erosion remarkably than Alfalfa grassland did. In natural grasslands, marram grassland reduced more amount of erosion than Humilis grassland did. Artificial grasslands significantly reduced soil erosion than natural grasslands did. Ploughed field had the highest erosion in farm lands, untillage corn field without stubble reduced wind-erosion 46.7%~48.6% as compared with the ploughed field. Stubble crops reduced soil erosion remarkably, although it was different for different crop types. Stubble corn field reduced soil erosion 58.1%~63.5% than the ploughed field did. Stubble buckwheat reduced erosion 50.5%~54.6% as compared with the plowed slope. In different terrains, windward soil erosion was as high 3.12~3.73 times as the value of leeward slope.[Conclusion] Artificial grassland should be increased in the area. Whereas, fields should not be ploughed or should be reduced for the ploughed area in winter and spring seasons; the reclamation of windward land should be diminished; fields should be covered in the winter or stubble should be retained after harvest to protect topsoil from wind erosion.