Effect of plant morphological traits on throughfall, soil moisture, and runoff

Abstract

Plant canopy morphology plays an important role in water balance, peculiarly in semiarid environments. Through a field experiment, the impact of plant morphology of two native plant species, Artemisia sacrorum Ledeb (ASL) and Spiraea pubescens Turcz (SPT), on partitioning rainwater was revealed. The results indicated that a fragmented leaf shape and apparently high stem density of ASL reduced the throughfall and its intensity effectively but facilitated soil moisture replenishment. Although SPT has a greater canopy cover and canopy depth than ASL does, larger throughfall, a smaller throughfall threshold, and stronger throughfall intensity were observed in the SPT site. Moreover, the SPT site has a higher soil steady infiltration rate, but produced more surface runoff and caused lower soil moisture content. This study highlights the importance of plant morphological traits, peculiarly leaf morphology, in partitioning rainwater in this semiarid region. We argue that plant morphological traits should be considered when selecting plant species for revegetation and assessing water balance.