Soil Hydraulic Properties of Plinthosol in the Middle Yangtze River Basin, Southern China

Yongwu Wang,Tiantian Yang,Jianwu Huang,Pei Tian,Hailin Zhang,Tieniu Wu

doi:10.3390/w12061783

Yongwu Wang, Tiantian Yang + Show 4 more

Open Access

https://doi.org/10.3390/w12061783

Copy DOI

Abstract

Soil hydraulic properties are ecologically important in arranging vegetation types at various spatial and temporal scales. However, there is still a lack of detailed understanding of the basic parameters of plinthosol in the Middle Yangtze River basin. This paper focuses on the soil hydraulic properties of three plinthosol profiles at Yueyang (YE), Wuhan (WH), and Jiujiang (JU) and tries to reveal the origin of plinthosol and the relationship among the soil hydraulic parameters. Discriminant analysis indicated that the plinthosol in the JU profile was of aeolian origin, while that in the WH and YE profiles was of alluvial origin; soil hydraulic properties varied greatly among these profiles. The proportion of macro-aggregates (>0.25 mm, weight%) in the JU profile (88.28%) was significantly higher than that in the WH (73.63%) and YE (57.77%) profiles; the water holding capacity and saturated hydraulic conductivity of JU plinthosol was also higher than that of WH and YE plinthosol; the fact that Dr and Di of the JU profile are lower than those of the YE and WH profiles illustrates the stability of JU plinthosol is better than that of YE and WH plinthosol, which is consistent with the fractal dimension of aggregates. The disintegration curves of white vein and red matrix demonstrated a large discrepancy in the JU profile, but these curves showed a similar trend in the WH and YE profiles. The differences in hydraulic properties might be ascribed to the origin of plinthosol, and the results of the fractal dimension also confirmed this conclusion. This study might provide a better understanding of the soil physical properties of plinthosol and shed light on the soil and water conservation measures in the Middle Yangtze River basin.

Highlights

Soil hydraulic properties are important for plant growth, soil and water conservation, and tillage operations [1]
This study focused on the soil water hydraulic properties of the plinthosol in the Middle Yangtze
Discriminant analysis showed, in the JU profile, the range of Y values was −12.37 to 6.94, and most samples were lower than −2.7411, while in the WH and YE profiles, all Y values were higher than −2.7411

Summary

Introduction

Soil hydraulic properties are important for plant growth, soil and water conservation, and tillage operations [1]. It includes, but not limited to saturated hydraulic conductivity (Ks ), water-stable aggregate (WSA), soil water retention curve (SWRC), and disintegration rate (Dr ) [2,3]. In the Middle Yangtze River basin, many environmental problems are challenging the carrying capacity of the natural ecosystems, such as soil erosion, land degradation, and soil pollution [4]. These problems are directly or indirectly related to the soil properties and soil quality.

Objectives

Results

Discussion

Conclusion