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结合地形监测了四川盆中丘陵区的典型浅丘1985～2005年间土壤养分变异情况,结果表明:研究区存在一定的水土流失;2005年相比1985年,土壤有机质、全氮和速效磷的含量都明显增加,其中速效磷的涨幅最突出,增幅为665.18%,碱解氮和速效钾的变化特征基本一致,呈现先下降后上升的趋势,总体分别下降了0.99%和5.23%;从浅丘不同地形部位之间差异上看,土壤有机质、全氮和速效磷含量都呈现冲沟>丘顶>丘坡的特征,丘坡的碱解氮、速效钾和速效磷含量变化幅度均较大,其中碱解氮下降28.09%、速效钾下降14.29%,速效磷则增加2568.18%;丘坡和冲沟的土壤退化指数介于0.2%～5%,土壤未见退化,而丘顶的土壤退化指数则在-0.14%～0.45%之间,前期有退化趋势,至1995年,由于植树造林和水土保持等工作的加强其退化趋势有所改善。
The results showed that there was a certain amount of soil and water loss in the study area. Compared with 1985, the content of soil organic matter, total nitrogen and available phosphorus The increase of available phosphorus was the most prominent, with an increase of 665.18%. The characteristics of both soluble nitrogen and available potassium were basically the same, showing the tendency of decreasing firstly and then increasing, decreasing by 0.99% and 5.23% respectively; The differences of soil organic matter, total nitrogen and available phosphorus showed the characteristics of gully> hilltop> hillside. The content of available nitrogen, available potassium and available phosphorus in the slope varied greatly, Degradation of nitrogen decreased by 28.09%, available potassium declined by 14.29% and available phosphorus increased by 2568.18%. Soil degradation index of hillside and gully ranged from 0.2% to 5%, no degradation of soil, -0.14% ~ 0.45%, with a tendency of degeneration in the early stage. By 1995, the trend of degeneration had been improved due to the strengthening of afforestation and water and soil conservation.