Optimal Fertilization Strategies for Winter Wheat Based on Yield Increase and Nitrogen Reduction on the North China Plain

In practice, most Chinese farmers usually apply excessive fertilizers to ensure wheat (Triticum aestivum L.) yield, resulting in environmental impacts. How to maintain an even increase wheat yield with less fertilizers is still not clear. This study evaluated the yield, quality, nutrient accumulation, and environmental costs of winter wheat under optimal fertilization management strategies. A field trial was set up with a randomized block design, constituted of eight different fertilization management strategies and four replicate plots. The results showed that optimal fertilization management strategy increased wheat yield and net benefit, and increased N, P, K accumulation, N and P fertilizer partial productivity and N and P uptake efficiency. Compared with the farmers' practice, the yield in the different optimal fertilization management strategies was increased by 2.21-8.42% through improving the spike number or the grain number per spike. Meanwhile, the net benefit increased by 6.83-11.29% in different optimal fertilization management strategies. Furthermore, NO3- leaching and nitrous oxide (N2O) emission in the different optimal fertilization managements were reduced by 25.50-35.15%, 48.80-60.26%, and 29.60-38.36%, respectively. In conclusion, CF3, CF1, 90%CF1 fertilization management can not only achieve high yield of wheat, but also improve economic benefits and reduce environmental costs, which are effective fertilization management strategies.