新疆奇台县化肥施用量变化及其与粮食单产的关系

根据新疆奇台县1989～2005年化肥施用量和粮食单产数据,采用趋势线法分析了该县化肥单位面积施用量的时闻序列变化,并采用相关分析对化肥施用量与粮食单产的关系进行探讨.结果表明:奇台县化肥单位面积施用量受粮食价格及化肥价格变化的影响较大,从1989年的65.65 kg·hm-2上升到最大值1998年的196.6kg·hm-2后下降,整个时间序列曲线呈抛物线状,且N、P、K施用比例较为合理,为促进粮食增产发挥了作用.1989～2005年粮食单产与单位面积化肥施用量存在明显的正相关关系,随施肥量的增加,粮食单产也趋于增加,当化肥施用量达到170kg·hm-2时,再增加化肥施用量对粮食的增产效果已不明显.因此,该县今后在粮食种植过程中应防止过量施肥,推广科学施肥,以更大程度地提高粮食产量.

Effect of chemical fertilizer application on grain yield in Qitai County,Xinjiang Uygur Autonomous Region

Based on official statistical data from 1989 to 2005, the characteristics of chemical fertilizer application in Qitai County, Xinjiang Uygur Autonomous Region were investigated by time series analysis. Then the relationship between grain yield and chemical fertilizer application was established through correlation analysis. Results show that average chemical fertilizer application in the county is influenced by the price of grains and fertilizers. From 1989 to 2005, fertilization application increased from 65.65 kg·hm-2 to 159.43 kg·hm^-2 and peaked in 1998 at 196.6 kg·hm^-2. The proportion of NPK fertilizer is moderate and has clearly increased grain yield. A significant direct correlation exists between grain yield and chemical fertilizer application rate. With increase in chemical fertilizer application, grain yield increases by many folds. When chemical fertilizer application is above 170 kg·hm^-2, increase in grain yield ceases to be significant. The best strategy is to control fertilizer application amount to avoid the potential pollution and other negative impacts. This can be achieved by paying appropriate attention to scientific application of fertilizers and sustainable development of agricultural production.