On the Characteristic Parameters of Nutrient Cycling in Forest Ecosystem

According to research on nutrient cycling of black locust forest in the Loess Plateau, a number of widely used characteristic parameters such as nutrient absorption ratio, nutrient utilizing efficiency, nutrient cycling intensity and nutrient biological cycling ratio have been analyzed and improved. Mean while, many new characteristic parameters such as litter equilibrium index and soil nutrient equilibrium index have been proposed and the calculation tenet of Deanglis's nutrient recycling index applied in forestland has been elaborated.