云贵高原红壤退化人工草地土壤肥力变化与有效施肥技术研究

Effective fertilization and soil fertility dynamics in deteriorate pasture of red-soil in Yunnan-Guizhou plateau of China

采用 N、P、K三因素肥料试验研究了氮磷钾肥配施对退化人工草地的增产效应以及土壤养分含量的影响。结果表明 ,NP处理与单施 N肥处理比较 ,1998年黑麦草增产 99.0 % ,鸭茅增产 2 2 .5 % ,白三叶增产 16 2 .5 % ;2 0 0 0年则为 2 19.1%、14 .6 %和 78.3%。在施用氮肥基础上 ,施用磷肥增产效果更为突出。在南方红壤退化人工草地中 ,由于土壤长期侵蚀的影响 ,土壤磷素已经退化到“谷底”水平 ,而投入系统中的磷素一部分被铁铝氧化物所固定 ,另一部分通过刈割或采食被带出系统 ,磷素损失量高。因此 ,在退化人工草地中首要的养分限制因子是磷 ,其次为钾。提高土壤 p H,降低红壤固磷能力 。

The fertilizer effect and soil nutrient dynamics were studied by three factor fertilizer experiment. The results showed that for the deteriorate pasture, the first restrict factor was phosphorus and the second was potassium. Compared with nitrogen treatment, marhed production was obtained by nitrogen add phosphorus treatment. Improving pH value,reducing phosphorus fixation of red soil and raising phosphate fertilizer effect were the methods for improving the deteriorate pasture in red soil region in Yunnan Guizhou plateau of China.