水肥耦合作用对土壤养分变化及春小麦生长发育的影响

水肥耦合最优饱和试验研究表明，在辽西半干旱区，低水量条件易引起N肥以氨态N挥发损失，当灌水量超过460mm时，高量施N可能会导致硝态N深层淋溶，高量施用P肥，土壤表层中OlsenP增加不明显，且灌水量变化对OlsenP在土壤各深度层次中含量影响不明显，N肥是影响春小麦生育前期叶面积指数和株高的主要因子，水分对春小麦株高的影响在生育前期不明显，至灌浆期时跃居主导地位，N、P配合施用可明显提高春小麦旗叶面积和株高。

Coupling Effects of Water and Fertilizers on Soil Nutrition and Growth of Spring Wheat

With a D Optimum saturation design, a field experiment was conducted to study the coupling effect of water and fertilizers on soil nutrition and growth of spring wheat in semiarid area of western Liaoning Province. The result shows that the amount of NH + 4 loss was easily happened under the condition of low irrigation, while NO - 3 N may be leached to the deep horizon of soil on the condition of over applying of nitrogen fertilizer and irrigation water above 460mm.However, soil Olsen P didn't increas significantly when phosphorus being over applied, and it didn't change obviously with the depth of soil horizons. Nitrogen was the main factor effecting height and leaf area index of spring in its early growing stage. Effect of water on height of spring wheat was low in its early growing stage, but significant in its grouting stage. Applying N with P at the same time can increase height and flag leaf area of spring wheat significantly.