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对陕北米脂人工经济林、神木退耕还林和榆林榆阳区防风固沙林具有代表性植被类型0~20 m土壤剖面水分特征的差异进行了研究,分析黄土丘陵区不同土地利用模式对深层土壤剖面水分分布和储存特征的影响及生态环境效应.结果表明:在0~20 m土层,不同位点具有代表性土地利用方式均影响土壤含水量的垂直分布;在整个剖面中,人工经济林土壤储水量有显著差异,为矮化枣树>未矮化枣树,储水量相差587.9 mm;神木退耕还林和榆林榆阳区防风固沙林土壤剖面中土壤储水量无较大差异,在神木整个剖面中土壤储水量的大小为退化人工草地>柠条林,储水量相差98.8 mm;在榆阳为荒草地>樟子松,储水量相差7.5mm.与未矮化枣树相比,人工经济林矮化枣树减少了对土壤水分的消耗,矮化枣树冠幅较小,降低了蒸腾作用,从而更加有利于土壤水分的可持续利用;人工柠条林和退化人工草地土壤水分含量无明显差异,这是因为退化人工草地过去为苜蓿地,根系分布深以及生物量大,对土壤深层水分利用较大所致;防风固沙林樟子松与荒草地整个剖面中的平均土壤含水量较低,土壤砂粒含量较高,土壤持水性差,土壤含水量随土壤深度的增加而增加,平均土壤含水量分别为3.4%和3.6%,且该地植物对深层土壤水分影响有限.综上,土壤剖面中土壤水分除了受土壤质地的控制,不同土地利用模式由于植物根系不同,对土壤水分也产生较大的影响.为此,选择合适的植物对于土壤深层水的保护和持续利用非常重要.
The differences of soil moisture characteristics of 0-20 m soil layer of representative vegetation type 0-2 m m were studied in milled pearl oyster plantations, Shenmu-plots and windbreak-fixing sandy forests in Yuyang district of northern Shaanxi Province. The effects of different land-use patterns on deep soil profile Water distribution and storage characteristics and eco-environmental effects.The results show that the vertical distribution of soil water content affects the soil water content at different sites in the 0-20 m soil layer. In the whole section, There was a significant difference in water volume between the jujube tree and the unwarped jujube tree, with a difference of 587.9 mm in water storage capacity. There was no significant difference in soil water storage between the Shenmu project of returning farmland to forestry and the windbreak and sand fixation of Yuyang district in Yulin. The soil water storage capacity was degraded Artificial Grassland> Caragana korshinskii forest, the water storage capacity difference was 98.8 mm; in Yuyang grassland> Pinus sylvestris var. Mongolica, the difference of water storage capacity was 7.5mm. Compared with the unwardened jujube tree, artificial economic forest dwarf Jujube reduced the consumption of soil moisture, dwarf jujube tree crown smaller, reducing transpiration, which is more conducive to the sustainable use of soil moisture; artificial Caragana forests and degraded artificial grassland Soil moisture content was not significantly different, because the degenerated artificial pasture was alfalfa past, deep root distribution and biomass, caused by the greater use of water in the deep soil; windbreak sand plantation and the weeds in the entire profile of the average soil Lower soil moisture, higher content of sand and soil, poor soil water holding capacity, soil moisture content increased with soil depth increasing, average soil water content was 3.4% and 3.6% respectively, and the plant had a limited impact on soil moisture. In summary, the soil profile in the soil profile is controlled by soil texture, and different land use patterns have a greater impact on soil moisture due to different plant root systems. Therefore, the selection of suitable plants for the protection and sustainable use of soil deep water Very important.