秸秆还田下土壤水分时间稳定性与玉米穗质量的相关性

Relationship between Temporal Stability of Soil Water and Corn Ear Weight under Straw Returning

摘要:

为揭示黑土区秸秆还田条件下农田土壤水分时间稳定性与玉米穗质量的相互关系，基于TDR法测得的土壤含水率（2017年6—9月）及称量法测得的玉米穗质量，在确定秸秆还田条件下农田土壤水分时间稳定性特征的基础上，量化分析其时间稳定性与玉米穗质量在单一尺度和多尺度上的相关特征。结果表明：随土层深度增加，土壤水分时间稳定性逐渐增强，且较深土层（40～60cm、60～80cm）土壤含水率较高的测点时间稳定性较强；随土层深度变化，土壤水分代表性测点有所不同，利用代表性测点土壤含水率可确定研究区域土壤最低含水率、最高含水率和平均含水率等信息，可为土壤水分估算与调控提供科学指导；时间稳定性与穗粒质量、穗轴质量相关程度随土层深度的变化趋势在单一尺度和多尺度上不同，大部分土层土壤水分时间稳定性与穗粒质量、穗轴质量的多尺度相关程度均大于单一尺度相关程度。多尺度相关分析能更深入地确定土壤水分时间稳定性与穗质量的相互关系，进而为深入揭示土壤水分对作物产量的影响机制提供理论依据。

Abstract:

In order to reveal relationship between temporal stability of soil water and corn ear weight under straw returning in black soil region, based on soil water content measured with TDR during June and September 2017 and corn ear weight measured with weighing method, the temporal stability of soil water under straw returning was firstly determined, and then the relationship between temporal stability of soil water and corn ear weight at the single scale and multiscale was quantitatively analyzed. The results showed that the temporal stability of soil water was increased with the increase of soil depth, and the sampling points in deeper soil layer (40～60cm and 60～80cm) which had higher soil water content had higher temporal stability; as soil depth changed, representative points of soil water under different situations were not identical, and the lowest, highest and average soil water contents for studied area could be determined with representative points of soil water content which could provide scientific guidance for estimation and regulation of soil water; the changing trend of correlation degree between temporal stability of soil water and grain weight per ear and axis weight per ear at multiscale was different from the one at the single scale, correlation degree between temporal stability of soil water in most soil layers and grain weight per ear and axis weight per ear at multiscale was more than the one at the single scale, and relationship between temporal stability of soil water and corn ear weight could be determined further with multiscale correlation analysis, which could provide theory basis for deeply revealing the influence of soil water on crop yield. Research results could provide theoretical foundation and guidance to estimate and manage soil water and increase crop yield.