通过４年定位试验研究结果表明，不施肥时，潮上土壤钾不断彼耗竭，ＡＲ０Ｋ渐降，最后稳定在１．１（ｍｍｏｌＬ－１）０．５左右。随着施钾量的增加，土壤供钾强度指标（ＡＲ０Ｋ）亦随之增加，两者呈显著正相关，ＡＲ０Ｋ值、施钾量与小麦、玉米的产量之间都呈二次抛物线关系。小麦、玉米最高产量时的施钾（Ｋ２Ｏ）量分别为５．４和７．４ｋｇ／亩，对应的ＡＲ０Ｋ值为３．６８４和３．０６６（ｍｍｏｌＬ－１）０．５。 The result of 4-year experiment indicates that soil potassium continues to be depleted when no fertilizer is applied, AR0K gradually decreases and finally stabilizes at about 1.1 (mmolL-1) 0.5. With the increase of potassium application, the soil potassium supply intensity index (AR0K) also increased, the two showed a significant positive correlation, AR0K value, potassium application and wheat, corn yield showed a quadratic parabolic relationship. Potassium (K2O) applied at the maximum yield of wheat and maize was 5.4 and 7.4 kg / mu, respectively, corresponding to an AR0K value of 3.684 and 3.066 (mmolL-1) 0.5.