Matching root water uptake patterns to fine root and soil water distributions

Abstract

Exploring the relationships between water uptake, ne root, and soil water is essential for many elds, such as plant physiology, ecological hydrology, and water conservancy. MethodsIn four Populus tomentosa stands with different ages (young and mature) and stand structures (low and high stand density), we matched root water uptake patterns obtained from stable isotope techniques with ne root and soil water distributions, respectively. The effects of soil water content and meteorological factors on these matching degrees were further explored. ResultsIt was found that the water uptake pattern was closer to soil water distribution than to ne root distribution in mature stands, while water uptake pattern matched both ne root and soil water distribution closely in young stands. Increased competition intensity within a stand would suppress the matching degree between water uptake patterns and ne root distribution, but would have little effect on the matching degree between water uptake patterns and soil water distribution. There is a relatively high positive or negative correlation between these two matching degrees in all four stands. Compared with the direct effect of soil water content, the in uence of meteorological factors on matching degrees was relatively weak. ConclusionThe results indicate that the expression of water uptake function of the young stand depends on a combination of root structure and available water resources, while the water uptake function of mature stands is driven more by available water resources rather than root structure.Therefore, the relationships between root water uptake, spatial root distribution, and soil water have been the subject of concern in many elds such as plant physiology, ecohydrology, and water conservancy

Effects of Different Drip Irrigation Rates on Root Distribution Characteristics and Yield of Cotton under Mulch-Free Cultivation in Southern Xinjiang

“…When the amount of irrigation is too much, the water will arrive too late to be consumed, the soil permeability will become poor, the root system will induce water-repellent growth [21,22] and the root volume will reduce or even die. In this study, the roots under the W2 and W3 treatments developed well and were widely distributed in the soil, and the root indexes were large, indicating that appropriate drought or appropriate water promoted the root development of filmless cotton, while too little water (W1) or too much water (W5) significantly affected the root growth and its spatial distribution in the soil was reduced, which was not conducive to the development of root function [23,24]. The RLD, RSA, RAD, RV and RWD of cotton were the largest in the 0-20 cm soil layer and 10 cm away from the main root, which shows a significant downward trend with the deepening of the soil layer and the increase in the distance from the main root, which is consistent with the results of previous studies [25,26].…”

Study on the Root Characteristics and Effects on Soil Reinforcement of Slope-Protection Vegetation in the Chinese Loess Plateau

“…Lateral roots can strengthen the cohesion between plant roots and soil. Under the condition that the internal friction angle of the soil is kept constant, the mechanical restraining force of the roots can increase the tensile strength of the soil [22]. The main root and its longitudinally growing lateral roots, which reach the deep soil layer, increase the shear strength of the soil by anchoring and strengthening the principle of resisting slope sliding [23,24].…”