水肥耦合对紫色土中小麦肥料减施效应的影响

为了认识水肥耦合对紫色土中小麦的影响特征及肥料减施效应，在四川盐亭县青峰村和四川盐亭农田生态系统国家野外科学观测研究站的石灰性紫色土上，于2018年10月至2020年5月，用小区和盆栽试验等方法，观测不同水肥耦合处理对小麦和土壤主要属性的影响。结果表明，水肥耦合对小麦生长和籽粒产量有明显的促进效应，浇水到田间持水量的80%左右时，其促进效应最大；肥料用量减少10%～20%，不会造成小麦的明显减产；水肥耦合主要提高了土壤养分有效性和土壤酶的活性，因而有明显的促进效应。水肥耦合是紫色土区减肥增效的一种有效措施，从而能有效防治区域的面源污染。

Water-Fertilizer Coupling: Effect on the Efficiency of Reduced Fertilization for Wheat in Purple Soil

The objective is to reveal the influence characteristics of water-fertilizer coupling on wheat and the efficiency of reduced fertilization in purple soil. Treatments of water-fertilizer coupling were conducted by plot and pot experiments at Qingfeng village and Yanting National Field Science Observation and Research Station of Farmland Ecosystem in Yanting County of Sichuan Province from October of 2018 to May of 2020. The effects of water-fertilizer coupling on the main properties of wheat and soil were measured. Results showed that water-fertilizer coupling had obvious promotion effect on wheat growth and grain yield, with the biggest positive effect being achieved when the watering amount was about 80% of the field water capacity. The wheat yield was not significantly decreased when fertilizer application amount was reduced by 10%-20%. Water-fertilizer coupling improved the availability of soil nutrients and the activity of soil enzymes, showing obvious promoting effect. Therefore, water-fertilizer coupling is an effective measure to improve the efficiency of reduced fertilization in purple soil region, so as to effectively prevent and control non-point source pollution.