Abstract: Micronutrient cycling in forest ecosystems is affected by soil conditi ons, litterfall turnover, throughfall properties, and some important ecological processes such as forest fire. This paper reviewed the related researches, with the focus on the micronutrient cycling in aboveground part of forest ecosystems and relevant affecting factors. In most forest ecosystems, litterfall and throug hfall were the important sources ensuring the balanced supply of micronutrients for growth forest, while forest fire, environmental pollution, and fertilization could also play important roles in the micronutrient cycling in some forest eco systems. Future studies on the micronutrient cycling in forest ecosystems should focus on the mechanisms governing micronutrient release from litterfall, the ef fects of global change and environmental pollution on the micronutrient cycling processes, and the balanced supply of micronutrients in restoration and reconstr uction of degraded ecosystems.

Key words: phosphate solubilizing fungus, carbon source, pH, response surface optimization., microbial density