1. Impacts of land use on phosphorus and identification of phosphate sources in groundwater and surface water of karst watersheds.
- Author
-
Chen, Hao, Han, Zhiwei, Yan, Xinting, Bai, Ziyou, Li, Qinyuan, and Wu, Pan
- Subjects
- *
WATER table , *FORESTS & forestry , *LAND management , *LAND use planning , *STABLE isotope analysis , *WATERSHEDS - Abstract
The thin soil layer with uneven distribution in karst areas facilitates the migration of phosphorus (P) to groundwater, threatening the safety of water sources seriously. To offer a scientific guidance for water pollution control and land use planning in karst areas, this study examined the relationships between land use and P in groundwater and surface water, and quantified the phosphate sources in Gaoping river basin, a small typical watershed in karst areas. Spatial distribution analysis revealed that the highest mean P concentrations in groundwater and surface water were in farmland and construction-farmland zones, respectively. Land use impact analysis showed that the concentration of P in groundwater was influenced positively by farmland but negatively by forest land. In contrast, the concentration of P in surface water was influenced positively by both farmland and construction land. The mixed end-element and Bayesian-based Stable Isotope Analysis in R (SIAR) model results showed that agricultural fertilizers were the main phosphate source for groundwater in farmland and forest-farmland zones, while urban sewage was the main source in the construction-farmland zone. For surface water, the main phosphate source was agricultural fertilizers in both farmland and construction-farmland zones. This study indicates that controlling P pollution in local water bodies should pay close attention to the management of land use related to human activities, including regulating sewage discharge from construction land and agricultural fertilizer usage. [Display omitted] • Groundwater phosphorus concentration is positively correlated with the proportion of farmland. • Fertilizers and urban sewage were the main sources of groundwater phosphate. • The sources of ground and surface waters phosphate in the karst region were quantified using multiple models. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF