Organic fertilization balances biodiversity maintenance, grass production, soil storage, nutrient cycling and greenhouse gas emissions for sustainable grassland development in China: A meta-analysis

Abstract

In recent decades, most grasslands in China have experienced varying degrees of degradation, and it is urgent to explore effective sustainable restoration models. Fertilizers have been widely used in grassland restoration projects. However, it remains unclear how fertilization can serve as an appropriate grassland restoration method to enhance ecosystem services and functions. Here, we conducted a comprehensive meta-analysis based on 79 studies to evaluate the responses of multiple ecosystem services and functions to inorganic and organic fertilization in grasslands of China. Inorganic fertilization increased grass production, soil storage and greenhouse gas emissions but often caused a loss of biodiversity maintenance. In contrast, organic fertilization increased biodiversity maintenance, grass production, soil storage, nutrient cycling, and greenhouse gas emissions relative to unfertilized, and increased more than inorganic fertilization. The positive effect of organic fertilization on ecosystem services and functions enhanced with increasing fertilization duration, while not observed under inorganic fertilization. Precipitation and elevation were the important influence factors affecting the effectiveness of organic fertilizer application. The appropriate organic fertilizer treatment needed to consider water and fertilizer balance as well as the unique environment of different grasslands. Therefore, we emphasize that long-term application of organic fertilizer may be a nature-based solution for promoting and maintaining ecosystem services and functions in grasslands of China.