Benefits and trade‐offs of replacing synthetic fertilizers by animal manures in crop production in China: A meta‐analysis

• Published in: Global change biology 2020-02, Vol.26 (2), p.888-900
• Main Authors: Zhang, Xiaoying, Fang, Qunchao, Zhang, Tao, Ma, Wenqi, Velthof, Gerard L., Hou, Yong, Oenema, Oene, Zhang, Fusuo
• Format: Article
• Language: English
• Subjects: Acidic soils; Agricultural land; Agricultural production; Agriculture; Agrochemicals; Ammonia; ammonia emissions; Animal manures; Animal wastes; Animals; Cereal crops; China; Crop Production; Crop yield; Crops; Emissions; Farmyard manure; Fertilizers; Food production; greenhouse gases; Livestock; livestock manure; Manure; Manures; Meta-analysis; Methane; Nitrogen; Nitrous Oxide; Oryza; Rice; Rice fields; Soil; Soil chemistry; Soil pH; Soil properties; soil type; Soils; Substitutes; Sustainability; trade‐offs
• ISSN: 1354-1013; 1365-2486
• DOI: 10.1111/gcb.14826

Recycling of livestock manure to agricultural land may reduce the use of synthetic fertilizer and thereby enhance the sustainability of food production. However, the effects of substitution of fertilizer by manure on crop yield, nitrogen use efficiency (NUE), and emissions of ammonia (NH3), nitrous oxide (N2O) and methane (CH4) as function of soil and manure properties, experimental duration and application strategies have not been quantified systematically and convincingly yet. Here, we present a meta‐analysis of these effects using results of 143 published studies in China. Results indicate that the partial substitution of synthetic fertilizers by manure significantly increased the yield by 6.6% and 3.3% for upland crop and paddy rice, respectively, but full substitution significantly decreased yields (by 9.6% and 4.1%). The response of crop yields to manure substitution varied with soil pH and experimental durations, with relatively large positive responses in acidic soils and long‐term experiments. NUE increased significantly at a moderate ratio (