黑土区坡式条田对水土流失、土壤水热及呼吸的影响

Effects of Sloping Contour Earth Bund on Soil Erosion, Moisture, Temperature, and Respiration in Black Soil Area of Northeast China

[目的]探索坡式条田在黑土区坡耕地水土保持和改善土壤环境中的作用,以期为坡式条田在坡耕地上的利用提供理论支持。[方法]基于野外试验,观测研究了坡式条田对径流产沙、土壤水热和土壤呼吸的影响。[结果](1)黑土坡面设置坡式条田具有良好的减流减沙效果,年均减少输沙率和减少地表径流率分别为78.3%和68.5%,土壤侵蚀模数为87.53 t/(km^2·a),控制在允许范围内;(2)修筑坡式条田显著提高土壤质量含水量(p<0.05),并能显著增加植被覆盖度(p<0.01);(3)研究区土壤呼吸与土壤温度显著相关,修筑坡式条田能够显著降低土壤呼吸速率,降低土壤碳素损失。[结论]黑土区坡式条田能够很好地防治水土流失,改善土壤水热和植被状况,且能降低土壤呼吸造成的C素流失,应在黑土坡耕地上推广应用。

[Objective]The function of sloping contour earth bunds with respect to soil and water conservation and environmental enhancement on sloping farmland in a black soil area was investigated in order to provide theoretical support for the use of sloping contour earth bunds on sloping farmland.[Methods]Field experiments were carried out to observe the effects of a sloping contour earth bund on soil erosion,the soil water content,soil temperature,and soil respiration.[Results]①The sloping contour earth bund had a remarkable effect on reducing the amount of soil erosion in the black soil area;the amount of erosion was 87.53 t/(km^2·a),which was less than the allowable amount of erosion.②Construction of the sloping contour earth bund significantly increased the soil water content(p<0.05)and the vegetation coverage ratio(p<0.01).③The soil respiration and soil temperature were significantly correlated in the research area,and the sloping contour earth bund clearly reduced the soil respiration rate and soil carbon loss.[Conclusion]The sloping contour earth bund exhibited remarkable effects for reducing soil erosion,improving the soil water content and temperature conditions,and reducing the soil respiration rate and soil carbon loss;hence,it is suitable for sloping farmland in the black soil area.