【摘要】 试验研究广西亚热带岩溶地区石灰性土壤K素特征结果表明,该区农田生态系统中棕色石灰土速效钾含量和速效钾可释放量能较好地反映土壤对当季作物的供K能力;当土壤速效钾含量降至30~32mg/kg时,作物难以吸收土壤中的K素,严重限制作物生长;土壤主要养分限制因子为土壤缺K,且P、S、B、Zn不足;棕色石灰土缓效钾含量和缓效钾可释放量不能正确反映土壤对当季作物的供K能力,但能较正确反映土壤的持续供K能力。施K有利于维持土壤K素平衡,通过增施K肥获得作物高产可行。更多还原

【Abstract】 The potassium characteristic of rendzina soil in the sub-tropic Karst of Guangxi was studied.The results show that the soil available potassium content and available potassium release amount can reflect the soil supply potassium capacity for a season crop in the agro-ecological system of sub-tropic Karst.When the soil availble potassium content is 30～32(mg/kg,)the crop is very difficult to absorb potassium and the growth is limited seriously.The main nutrient-limited factor of soil is potassium.Phosphorus,surphur,boron and zinc are not enough for crop growth.Slow potassium content and slow release potassium content can not show the soil supply potassium capacity,but they can show the soil sustainable supply potassium capacity.Applying potassium fertilizer is good for the balance of potassium in soil and can increase the crop yield.更多还原