Analysis of Total Organic Waste and Potential for Replacing Chemical Fertilizers in China

The quantity of organic waste produced in China is enormous, and knowing the present situation of the country's total amount of organic waste and its nutritional supplies is important for both resource use and environmental safety. In order to analyze the potential for the utilization of organic wastes and the carrying capacity of the land, the current total amount of organic waste and its nutrient resources in China were estimated by reviewing Chinese statistical data and published literature. The study's objective was the production of major organic wastes (straw, livestock and poultry manure, rural human waste, sludge, and domestic organic waste) in China in 2021. The findings indicated that in 2021, its total resource would be 11.61x108 t, and its nutritional content would be 4075.24x104 t. In 2021, the nutrient contents of N, P2O5 and K2O in the total nutrient content of organic waste in China were 1571.43x104 t, 733.52x104 t and 1770.29x104 t, respectively. In 2021, the N nutrient content of China's organic waste accounted for 67.48% of the recommended N application, the P2O5 nutrient content accounted for 69.30% of the recommended phosphorus application, and the K2O nutrient content accounted for 131.09% of the recommended potassium application. From the perspective of China's overall scale, China has a large space for carrying and consuming livestock and poultry manure. When calculating the land carrying capacity based on nitrogen, the land carrying capacity index of China was 0.23, and when calculating the land carrying capacity based on phosphorus, the land carrying capacity index of China was 0.54. In general, China has a massive amount of organic waste materials and nutrients, with plenty of room for use. The current magnitude of farming places a minor strain on the land carrying capacity of animal manure. If the nutrient resource structure of China's organic waste remains unchanged and the entire amount is returned to the field, the nitrogen, phosphorus, and potassium nutrients in organic waste can satisfy 67.48%, 69.30%, and 100% of the nutrient requirements of various types of crops, respectively.