Abstract: In this paper,an on-the-spot sampling and survey method for studying the soil nutrient cycling in a regional scale was discussed,with considering the principles of representation,reproducibility,randomness and timeliness.Firstly,some representative sampling areas in a definite region should be selected,based on the relevant hypsographic maps and airscapes.During the course of sampling soil and plant,a field survey related to the sampling sites should be carried out to understand the natural affecting factors on the soil nutrient cycling in a regional agro-ecosystem scale.Moreover,the farmers’ basic status,crop production,and applied amount of fertilizers and their allotment should be also investigated.A case study of nutrient cycling in subtropical regions of China was carried out to approach the application of the method in the study of soil nutrient cycling in some regions.

Key words: Taiwanese red tilapia, Temperature, Energy budget