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在柳江县复石灰水稻土进行长期定位试验，每造每６６７ｍ２施钾（Ｋ２Ｏ）４．５ｋｇ水稻增产４５．６％～６２．８％；施干稻草１５０ｋｇ增产４３．７％～５２．９％。长期不施用钾肥，土壤钾素经过２年下降后，维持在一个“恒定水平”；在早稻～晚稻～休间耕作制度下，春季为土壤钾素恢复期，夏季和秋季为土壤钾素消耗期，呈年周期性变化；在水稻生长期中，分蘖～孕穗期土壤钾素下降最速，孕穗～成熟期下降甚微。不施用钾肥，土壤每年每６６７ｍ２亏失３．７～５．７ｋｇＫ２Ｏ；６６７ｍ２年施Ｋ２Ｏ９ｋｇ，可弥补土壤钾素亏失５２．６％～７５．７％；施稻草３００ｋｇ，弥补率为３３．３％～７０．３％；钾肥和稻草并用，基本上可达到土壤钾素平衡。
In Liujiang County, long-term locating experiments were carried out on paddy-lime soils with a yield of 45.6% -62.8% for 4.5 kg of K2O applied per 667m2 of paddy soil and 43.7% -52.9% . In the long-term, no potassium fertilizer was applied. After two years of decline, the soil potassium was maintained at a “constant level.” In the early rice-late rice-tillage tillage system, spring was soil potassium recovery in spring and summer and autumn were soil potassium depletion , The annual change of annual; in the rice growth period, tillering ~ booting the soil potassium the fastest decline, booting ~ maturity decreased slightly. Without potassium fertilizer, the annual loss of soil per 667m2 3.7 ~ 5.7kgK2O; 667m2 annual K2O9kg, can make up the soil potassium loss 52.6% ~ 75.7%; straw 300kg, make up rate of 33.3 % ~ 70.3%; Potash and straw and can basically achieve the balance of soil potassium.