棉花各生育期精细水肥调控对滴灌棉田土壤盐分变化的影响

目的]滴灌棉田土壤次生盐渍化逐渐成为生产中关注的一个问题.探讨棉花生育期水肥调控对滴灌棉田土壤盐分变化的影响.方法]在新疆库尔勒市进行大田试验,在总施肥量相同情况下棉花各生育阶段施肥比例不同时,测定分析各生育期剖面土壤电导率、水分含量、棉田光照强度.结果]棉花生长期进行适宜的水肥耦合管理有可能在生长期结束时降低或调控表层土壤含盐量.在各生育阶段施肥量一定、需要多次追肥情况下,蕾期采取"前重后轻"、花铃期前期采取"多次等比例"、盛铃期采取"前轻后重"施肥策略,能有效降低0～60 cm根层土壤盐分含量.结论]调控棉花生长增大田间郁闭程度有利于提高土壤水分含量、降低土壤含盐量.

Effects of Regulation and Control of Water and N Fertilizer on Soil Salt Content in Cotton Field under Mulch-film Drip Irrigation

【Objective】The soil secondary salinization in cotton field under mulch-film drip irrigation has been an important problem in production.【Method】The paper analyzed change of soil EC,water content and field illumination intensity in different growth stage of cotton according to different fertilizer rate but same usage.【Result】Appropriate management of water and N fertilizer could decrease or regulate salt content of top soil.If N fertilizer was applied according to different fertilizer rate but same usage in growth period of cotton,it could regulate soil salt content in root area from 0 cm to 60 cm.【Conclusion】So increasing cotton canopy intensity was helpful to increase soil water content,and decrease soil salinity.