Year: 2020
Type: article
Abstract: Background and Objective: Although desert dams create storage reservoirs that recharge ground water, irrigate desert agriculture and protect against flash floods, there is controversy about their effects on ecosystem.Work in this study was carried out to provide first environmental impact assessment of Wadi Jazan desert reservoir by studying its effects on soil and floristic composition.Materials and Methods: Soil analysis included studies of soil types and characteristics.Vegetation analysis included study of plant distribution, life forms, growth habits, carbon isotope discrimination, CO 2 fixation pathways, species drought and salt tolerance ranges.Results: Soil analysis revealed changes in soil type around reservoir from common sand-silt to clay and clay-loam types reflecting reservoir-induced changes in sedimentation patterns.Soil analysis also revealed increased soil electric conductivity and total dissolved solids in reservoir vicinity denoting increased soil salinity.High reservoir level during wet season enables water to cover vast areas with subsequent evaporation during long hot dry season resulting in salt accumulation and increased soil salinity.Vegetation analysis revealed prevalence of salt tolerant C3 species in saline soil in reservoir vicinity that was reversed with prevalence of C4 drought tolerant species as distance from reservoir increased.Presence of non-native aquatic and wetland species are due to recruitment facilitated by reservoir.Conclusion: Wadi Jazan desert reservoir modified sedimentation pattern, facilitated establishment of invasive aquatic plants and induced changes in regional floristic diversity and distribution.
Source: Asian Journal of Plant Sciences
Authors: Osama H. Sayed, Yahya S. Masrahi, M. Remesh
Institution: Jazan University
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3036623547