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太湖地区人地关系紧张 ,环境问题尤其是地表水体富营养化严重 ,农田生态系统的养分收支和土壤养分状况不仅关系到农业的高产稳产 ,对区内的水环境质量也有着重要的影响。典型区的实地调查和采样分析结果表明 ,自 2 0世纪 80年代初以来太湖地区农田生态系统中的氮、磷一直处于盈余状态 ,且盈余量不断增加 ,土壤钾素则长期亏缺 ,但近年来有所缓和。区内土壤有机质、全氮、全磷和有效磷含量近 2 0年来都有较大幅度的提高 ,速效钾含量在 2 0世纪 90年代中期以前呈下降趋势 ,近年来有所回升。主要类型土壤的pH也呈降低的趋势。
The relationship between man and land in the Taihu Lake is tense. Environmental problems, especially the surface water bodies, have serious eutrophication. The nutrient balance and soil nutrient status of farmland ecosystems are not only related to the high and stable agricultural production, but also have an important impact on the quality of water environment in the area. Field surveys and sampling analysis of typical areas show that since the early 1980s, nitrogen and phosphorus in farmland ecosystems in the Taihu Lake region have been in surplus and their surplus has been increasing while soil potassium has been deficit for a long time. However, recent years To ease. The contents of soil organic matter, total nitrogen, total phosphorus and available phosphorus in the area have all increased greatly in recent 20 years. The content of available potassium has been on the decline before the mid-1990s and recovered in recent years. The pH of major types of soils also showed a decreasing trend.