科尔沁沙地南缘不同林草措施土壤抗冲性及其与物理性质的关系

【目的】研究水蚀风蚀交错区土壤抗侵蚀特性对不同林草措施的响应。【方法】采用室内抗冲槽原状土冲刷和土壤物理性质分析相结合的方法,研究了科尔沁沙地南缘不同林草措施土壤抗冲特性及其与物理性质的关系。【结果】土壤冲刷过程中,不同林草措施下出现产流后的4 min之内变化较大,随着冲刷试验的进行逐渐降低,并逐渐达到相对稳定状态;不同林草措施土壤冲刷过程平均径流含沙量表现为荒草地>花生地>灌木林地>樟子松林地;不同林草措施土壤抗冲性变化与土壤冲刷过程含沙量呈反比,随冲刷时间延长,总体来说与冲刷时间越长,抗冲性能越强的规律相符合,且这种变化规律不受林草措施变化而改变。径流结束时不同林草措施下的土壤抗冲性表现为花生地<荒草地<灌木林地<樟子松林地。土壤抗冲性与土壤体积质量极显著负相关,与土壤孔隙度显著正相关,土壤抗冲性指数与砂粒极显著负相关、与粉粒和黏粒正相关,但均不显著,与土壤持水性并无显著性关系。【结论】林草措施能够显著提高土壤抗冲性能,以樟子松效果最强。

Soil Anti-scourability and Its Relationship with Physical Properties of Different Forest and Grass Measures in the Southern Margin of Horqin Sandy Land

【Objective】Explore the response of soil anti-scourability characteristics to different forest and grass measures in the water-wind erosion crisscross region.【Method】The soil anti-scourability characteristics of different forest and grass measures and their relationship with physical properties were studied by combining indoor anti-erosion trough undisturbed soil erosion and soil physical properties analysis.【Result】In the process of soil erosion, the runoff yield under different forest and grass measures changed greatly within 4 minutes, and gradually decreased with the extension of time, and tended to be relatively stable. The average runoff sediment concentration of different forest and grass measures in soil erosion process was grassland > peanut land > shrub forest land > Pinus sylvestris var. Mongolica land. The change of soil erosion resistance with different forest and grass measures was inversely proportional to the sediment content in the process of soil erosion. With the extension of time, the rule that the longer the erosion time was, the stronger the erosion resistance was accorded with on the whole, and the relationship was not changed by the change of forest and grass measures. At the end of runoff, the soil anti-scourability of different forest and grass measures was Pinus sylvestris var. Mongolicat land > shrub forest land > grassland > peanut land. Soil anti-scourability was negatively correlated with soil bulk density, and positively correlated with soil porosity. Soil anti-scourability index was negatively correlated with sand grains and positively correlated with silt grains and clay grains, but it was not significantly correlated with soil water holding capacity.【Conclusion】Forest and grass measures could significantly improve soil anti-scourability characteristics, with the best effect of Pinus sylvestris var. Mongolicat land.