鄂南红壤丘陵区种植结构调整对土壤养分的影响

研究了鄂南红壤区不同种植模式的旱地及坡荒地、不同轮作模式的水田、水田改旱菜地的土壤养分状况。本区土壤有机质含量和氮素含量较低,磷素普遍缺乏,钾素含量较低且呈下降趋势。土壤有机质及氮含量呈现水田类>水田改旱地类>旱地类;土壤磷含量则是水田改旱地类>水田类>旱地类;水田类钾含量明显低于旱地类和水田改旱地类,而且三熟制油菜-西瓜-晚稻种植模式下,土壤全钾及速效钾含量呈下降趋势。水田改为旱作是改善土壤水分状况的有效措施。

Effects of rotation cropping system on soil nutrients in hilly region of red soil in south Hubei

Soil nutrients content of upland, paddy field and vegetable plot changed from paddy field were measured under the 10 rotation cropping systems in the hilly region of red soil in south Hubei. The organic matter and nitrogen were commonly low and the phosphorus was deficiency, where the potassium was gradually reduced in the area. It was found that the content of organic matter and nitrogen in the rotation cropping system could be set in sequence from high to low, for paddy field, vegetable plot changed from paddy field, and upland, while the content of phosphorous might be set an other sequence, for vegetable plot changed from paddy field, paddy field, and upland. The content of potassium was remarkable lower in paddy field than in upland, especially low in three harvests a year (rape seed-watermelon--rice). Changing to vegetable plot can remarkable reform soil moisture region of paddy soil.