Work

Characteristics and Mechanisms of the Impact of Heterogeneity in the Vadose Zone of Arid Regions on Natural Vegetation Ecology: A Case Study of the Shiyang River Basin

Year: 2025

Type: article

Abstract: As a critical link connecting groundwater and vegetation, the vadose zone’s lithological structural heterogeneity directly influences soil water distribution and vegetation growth. A comprehensive understanding of the ecological effects of the vadose zone can provide scientific evidence for groundwater ecological protection and natural vegetation conservation in arid regions. This study, taking the Minqin Basin in the lower reaches of China’s Shiyang River as a case, reveals the constraining effects of vadose zone lithological structures on vegetation water supply, root development, and water use strategies through integrated analysis, field investigations, and numerical simulations. The findings highlight the critical ecological role of the vadose zone. This role primarily manifests through two mechanisms: regulating capillary water rise and controlling water-holding capacity. They directly impact soil water supply efficiency, alter the spatiotemporal distribution of water deficit in the root zone, and drive vegetation to develop adaptive root growth patterns and stratified water use strategies, ultimately leading to different growth statuses of natural vegetation. During groundwater level fluctuations, fine-grained lithologies in the vadose zone exhibit stronger capillary water response rates, while multi-layered lithological structures (e.g., “fine-over-coarse” configurations) demonstrate pronounced delayed water release effects. Their effective water-holding capacities continue to exert ecological effects, significantly enhancing vegetation drought resilience.

Source: Sustainability

DOI: 10.3390/su17146605

Authors: Haohao Cui, Jinyu Shang, Xujuan Lang, Guanghui Zhang, Qian Wang, Mingjiang Yan

Institutions: Ministry of Natural Resources, Chinese Academy of Geological Sciences, Hebei GEO University

Language: English

Topic: Soil and Unsaturated Flow

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Life on land, Clean water and sanitation

Open Access status: gold

Estimated APC paid: $2,896