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黄土高原水蚀风蚀交错区在强烈的水蚀风蚀作用下,土壤养分流失严重,土壤退化明显。但不同的土地利用方式,这种退化规律有较大的差异。以位于黄土高原水蚀风蚀交错区的六道沟小流域为研究区,分析坡耕地和荒草坡地土壤养分特征,探讨土壤养分与土壤质地及水分的相关性。结果表明:(1)水蚀风蚀交错区各养分含量都较低,其养分含量表层均高于下层,坡耕地高于荒草地;土壤各养分上下层比值越大,土壤的供肥持续能力越差;(2)坡耕地土壤养分含量表现出与坡地水土流失相似的规律,从坡顶部到坡底呈现先减小后增大的趋势;(3)土壤水分含量影响土壤质地变化,并与土壤有机质和全氮关系最好,与有效态氮的关系较密切;(4)土壤养分含量与土壤质地的吸附作用有关,组成物质越细,吸附能力越强,但这种吸附能力还与不同粒级组成的比重有关,其机理有待于进一步研究。
Under the action of strong water erosion and wind erosion, the soil nutrient loss is serious and the soil degeneration is obvious. However, different land use patterns have great differences in this law of degradation. Taking Liudaogou watershed located in the ecotone of water erosion and erosion in the Loess Plateau as study area, the characteristics of soil nutrients on sloping fields and wasteland were analyzed, and the correlation between soil nutrients and soil texture and water content was discussed. The results showed that: (1) The water and wind erosion ecotone had low nutrient content, the nutrient content was higher in the surface layer than in the lower layer, and the slope farmland was higher than that in the wild grassland. The greater the ratio of soil nutrients was, ; (2) Soil nutrient content in sloping farmland showed a similar pattern with that of sloping land, showing a tendency of decreasing firstly and then increasing from the top of slope to the bottom of slope; (3) Soil moisture content affected soil texture change, (4) The soil nutrient content is related to the adsorption of soil texture. The finer the composition, the stronger the adsorption capacity, but the adsorption capacity is also related to different grain size The proportion of the composition, the mechanism remains to be further studied.