WEI Yan-hong, YUAN Zhi-fa, GUO Man-cai. Trend Surface Analysis of Effects of Fertilization Level on Dry-land Wheat Yield in Gully Regions of Loess Plateau[J]. Bulletin of Soiland Water Conservation, 2014, 33(1): 203-206.
WEI Yan-hong, YUAN Zhi-fa, GUO Man-cai. Trend Surface Analysis of Effects of Fertilization Level on Dry-land Wheat Yield in Gully Regions of Loess Plateau[J]. Bulletin of Soiland Water Conservation, 2014, 33(1): 203-206. DOI: 10.13961/j.cnki.stbctb.2014.01.053.
Effects of different fertilization proportions of N and P on dry-land wheat yield in gully region of the Loess Plateau in the condition of normal rainfall were studied based on the long-term experiment in Changwu
Shaanxi Province. A trend surface model of dry-land wheat yield in the gully regions was constructed using trend surface analysis. Fertilization proportions for higher wheat yield were found and the fertilization proportions for the highest yield were N=178.169 kg/hm2 and P=198.405 kg/hm2. The maximum wheat yield was 6 152.6 kg/hm2. Wheat yield with different N and P proportions in the condition of normal rainfall can be predicted by the trend surface model
which provides a theoretical basis for the actual agricultural production.
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