Variation Characteristics and Influencing Factors of Soil Moisture Content in the Lime Concretion Black Soil Region in Northern Anhui

Mingcheng Du,Zhenlong Wang,Guoqing Wang,Qinli Yang,Yongsheng Hu,Cuishan Liu,Zhenxin Bao,Junliang Jin,Yanli Liu,Amgad Elmahdi,Nan Gu,Jianyun Zhang,Haowen Liu

doi:10.3390/w13162251

Abstract

Soil moisture content (SMC) is an important factor affecting crop growth. Based on the field SMC data measured at the Wudaogou experimental station from 1989 to 2019, two typical crop types, wheat and maize, were selected. By combining the groundwater depth, crop growth period, and meteorological factors in the same period, and using classical statistics and redundant analysis (RDA) methods, the characteristics and influencing factors of SMC changes in vertical profiles of different crops were compared and analyzed. The results showed that the SMC and average daily water storage of wheat were greater than that of maize. The crop growth mainly consumed 0–60 cm SMC. The SMC in this area was moderately variable; the SMC of 0–30 cm belongs to the active layer, and the SMC of 30–100 cm belongs to the sub-active layer. The RDA method identified ground temperature, groundwater depth, relative humidity, and the wheat growing period as the main factors affecting soil moisture variation in wheat fields; groundwater depth, relative humidity, and water vapor pressure differences were the main factors affecting soil moisture variation in maize fields. The results can provide a basis for accurate prediction of soil water dynamics and thus provide a reference for irrigation decision-makers.

Highlights

Soil moisture content (SMC) is an important variable in understanding hydrological cycle processes
We analyzed the dynamic characteristics and the influencing factors in SMC based on the long series of field-measured SMC data from 1989–2019 at the Wudaogou Hydrological experiment station
The results showed that the SMC at different depths in wheat fields was higher than in maize fields, and the SMC of the field showed a trend of increasing and decreasing with the increase of soil depth

Summary

Introduction

Soil moisture content (SMC) affects a wide range of interactions between earth systems in the soil–vegetation–atmosphere continuum, such as hydrological and biological processes, and is an important driver of material and energy transfer [1,2,3]. It is an integral part of the hydrological cycle and it is one of the important parameters describing the processes of the terrestrial hydrological cycle, controlling, to varying degrees, the processes of runoff, evaporation, and infiltration [2,4,5]. Based on the coefficient of variation (CV) and standard deviation of soil moisture, the soil layer is divided into four layers: the rapid change layer, active layer, sub-active layer, and relatively stable layer [7]

Methods

Results

Conclusion