丘岗稻田地下水位动态及对土壤氮磷有效性的影响

对红壤丘岗区渍潜田地下水位动态变化规律及对土壤氮磷有效性的影响进行了研究。结果表明，渍潜田地下水位的月变化具有十分明显的规律性，一般以秋冬季节（1－3月份和9－12月份）地下水位最低，而以春夏季节（4－8月份）地下水位最高，故以早稻受渍害最为严重，其原因主要是受降雨和灌溉的共同影响。根据渍潜田地下水位的变化特点不同，可将其分为地下水位和相对稳定型和非稳定型两种类型，并提出了相应的水分管理模式，地下水位的变化能明显影响土壤养分的有效性，随着地下水位的升高，土壤有效氮和磷含量下降。渍潜田土Fe-P和O－P含量也有随地下水位的升高而呈下降的趋势，其含量亦显著低于非渍潜田土壤，因而导致了土壤磷素有效性的下降。

Dynamic Change of Groundwater Level in Waterlogged Gleyed Paddy Soils in Hilly Red Soil Region and Its Effects on Availability of Soil Nitrogen and Phosphorus

Gleyed paddy soil is a major type of low yield paddy soil in hilly red soil region in south China. It mainly results from the high groundwater level and poor drainage due to low topographical location. In addition, inappropriate management is another factor attributed to its formation. There has been much work on the formation,physical and chemical characteristics,nutrient supply and amelioration of gleyed paddy soil.However, very little information is available on changes in groundwater level and its effe...