Abstract: This paper reviewed the research advance in the budget of potassium in agroecosystems and the reuse of recycled potassium.Some strategies were brought forward to solve the problems in potassium cycling.In China,the amount of applied fertilizer potassium was far less than that of the potassium carried off by crops from soil,and thus,potassium was of negative balance all along.Soil potassium fertility was decreased continually,and the areas available to potassium application was extending.Though the application rate of potassium was increasing,the potassium balance was still of negative.To maintain and improve soil potassium fertility and to obtain high and stable crop yield,enough attention should be paid on soil potassium balance,structural optimization of agroecosystems,regulation of water and fertilizer,and combined application of organic and chemical fertilizers.

Key words: Soil type, Soil fertility, Soil nutrient, Rhizospheric effect, Maize