Effects and potential of optimized fertilization practices for rice production in China
Résumé
AbstractOptimized fertilization practices are a promising management strategy for sustainable rice production. Green manuring, straw incorporation, postponing nitrogen (N) application, formula fertilization, combined application of organic and inorganic fertilizers, reducing fertilization, deep fertilization, slow/controlled-release fertilizers (S/CRFs), and biochar addition are nine frequently used optimized fertilization practices in China. The nitrogen use efficiency (NUE) improvement, yield increase, and N loss-reducing effects of these practices were analyzed based on multisite studies across China. An index system considering the applicability and effects of various practices was developed to identify their potential distributions. The results indicated that 76.5% of all paddies in China are overfertilized regions under the current rice yields. Optimized fertilization practices were mainly adopted in central and eastern China regions with serious water pollution and excessive fertilization. Postponing N application, S/CRFs, and formula fertilization had wide applicability nationwide, suitable for 100% of all paddies, followed by straw incorporation (98.8%), deep fertilization (81.4%), green manuring (67.0%), reducing fertilization (44.0%), biochar addition (33.7%), and combined application of organic and inorganic fertilizer (23.4%). Overall, except for reducing fertilization, which decreased yields by an average −2%, most practices increased yield by more than 5% and reduced total N losses by more than 15%. Reducing fertilization, postponing N application, S/CRFs, straw incorporation, and green manuring are five eco-friendly practices with wide distribution, low inputs, and good effects. By fully implementing the recommended combination scenarios based on the five preferred practices at the country level, the total yield increasing rate and N loss-reducing rate were 3~9% and 15~35%, respectively. Optimized fertilization in China has noticeable potential to alleviate agricultural non-point source pollution while ensuring rice yield.
Origine | Publication financée par une institution |
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