滴灌土壤养分的空间变异及其对春小麦生长特性和产量的影响机制

Drip irrigation technology has been applied in Wheat in2008.Not suitable for planting crops using traditional understanding was broken. Water-saving and yield-increasing effect is significant and has good application prospect. Drip irrigation area of Wheat is 4635000 acres. The drip irrigation of basic research about wheat is weak.The study of the irrigation system and output is more, but the study of the fertilization and Soil Nutrient Spatial Pattern is rare.the development of drip irrigation technology of wheat is restricted. The time and position resolution based on size, using the method of spatio-temporal substitution, We study the soil of ground irrigation and drip irrigation in different years. we analyze the soil nutrients spatial pattern, dynamic characteristics of interannual and drip irrigation on the spatial and temporal correlation. We study the temporal and spatial variation of accumulation of soil nutrients Then the trend of drip soil fertility quality was revealed. We study spatial variability and their synergistic mechanism about soil nutrient, drip irrigation of wheat growth characteristics and yield under different fertilization by continuous monitoring method. We analysize Soil Micro-spatial variation and temporal distribution of drip Irrigation under different fertilization, and explore the relationship between the spatial variation,and wheat growth characteristics and yield of drip irrigation, the theoretical and technical basis was provided for determining reasonable sampling number, selecting representative sampling sites, conducting nutrient management based on the minimum fertilizer unit, improving the mapping accuracy and perfecting the system of Wheat Fertilization Techniques of drip irrigation in spring.

2008 年开始的滴灌小麦大田生产打破了其不适宜密植作物应用的传统认识，因节水增产效果显著得以迅速推广应用，2013 年仅地方滴灌小麦面积达170 万亩，比上年增长45.3%。目前针对滴灌小麦的研究较少,主要集中在灌溉制度和产量上，与之相配套的施肥技术和土壤养分空间格局及变异特征少见报道，基础研究的薄弱限制了滴灌小麦技术的发挥。本研究对比地面灌选取不同滴灌年限的土壤作为研究对象，基于时间及位置分辨率大小，采用时空互代的方法，分析滴灌土壤养分空间格局、年际动态变化特征及其对时空的相关关系，研究滴灌土壤养分积累时空变异规律，揭示滴灌土壤肥力质量演变趋势。连续定位监测研究分析不同施肥量滴灌根区土壤养分微时空分布动态变异,阐明其与春小麦生长特性和产量的相关性及影响机制，为确定滴灌土壤合理取样数、选择代表性取样地点、划分最小施肥单元、提高制图精度及完善滴灌小麦施肥技术体系等提供理论和数据依据。

对密植作物小麦滴灌模式下农田土壤养分时空特征及其生长特性进行研究，从土壤养分运移及空间格局分布上研究与之相配套的施肥技术，为充分发挥滴灌小麦技术增产及化肥减施提供理论及技术基础。分析滴灌土壤养分空间格局、年际动态变化特征及其对时空的相关关系，研究滴灌土壤养分积累时空变异规律，揭示滴灌土壤肥力质量演变趋势；分析不同施肥量滴灌根区土壤养分微时空分布动态变异,阐明其与春小麦生长特性和产量的相关性及影响。本研究对比地面灌选取不同滴灌年限的土壤作为研究对象，基于时间及位置分辨率大小，采用时空互代的方法，连续定位监测研究，借助地理信息技术等手段分析研究结果表明，不同滴灌年限（1、3、5、7年）农田小尺度、微尺度土壤养分垂直分布的变化规律基本一致，不同滴灌年限的养分要素含量基本随着土层深度的增加整体呈现下降趋势；随滴灌年限增加，盐分由滴灌中心向两侧及深部土层迁移，应用滴灌技术7年后，滴头下0-20cm土层脱盐效果较为明显，盐分逐渐向滴头下方60cm以下、距滴头水平距离40cm以外区域集聚；随着施氮量（N0、N1、N2、N3、N4）的增加不同生育期（拔节、抽穗、开花和灌浆期）的SPAD值处于增加的趋势，总小穗数、千粒重及产量呈现先增加后降低的趋势，施氮量增加有利于土壤养分的积累。