Assessment of spatiotemporal risks for nationwide groundwater nitrate contamination

Zhan, Yang1,2,3; Guo, Zhilin1,2; Ruzzante, Sacha4; Gleeson, Tom4,5; Andrews, Charles B.1,2; Babovic, Vladan3; Zheng, Chunmiao1,2,6

2024-10-15

10.1016/j.scitotenv.2024.174508

SCIENCE OF THE TOTAL ENVIRONMENT   影响因子和分区

0048-9697

1879-1026

National assessments of groundwater contamination risks are crucial for sustaining high-quality groundwater supplies. However, traditional methods often treat groundwater contamination risk as a steady-state indicator without considering spatiotemporal variation in risk, both geographically and over time, caused by anthropogenic and climatic factors. In this work, XGBoost, a tree-based algorithm, was applied to comprehensively analyze the drivers of groundwater contamination from nitrate, using data on 13 physical features (as used by the index-based ranking method DRASTIC) and 30 anthropogenic features from 1985 to 2010 in the contiguous United States (CONUS). The results indicate that physical features controlling the transport processes, particularly those affecting contaminant travel time from land surface to groundwater (depth to water table and transmissivity), were the dominant factors for nitrate contamination in groundwater. This was followed by features representing the potential nitrogen loading. Positive correlations between most features and the nitrogen loading time (year) were found, suggesting their growing influence on contamination risk. Based on the drivers identified for nitrate concentrations exceeding 10 mg/L in groundwater and their varying temporal contributions, this study proposes a reformulated index-based method for contamination risk assessment. With this method, an overall accuracy of around 70 % was achieved based on the validation data set. The predicted high-risk areas are mainly intensive irrigation regions, such as the High Plains, northern Midwest, and Central Valley. This new approach contributes to a more accurate and effective assessment of the contamination risks of groundwater on a regional and national scale under temporally varying environmental conditions.

Contamination risk assessment Spatiotemporal dynamics Groundwater quality Anthropogenic impacts

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[42377045] ; Shenzhen Science and Technology Innovation Committee[JCYJ20210324105009024] ; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control[2023B1212060002] ; High-level special fund[G03050K001]

Environmental Sciences & Ecology

Environmental Sciences

WOS:001270312400001

ELSEVIER

20242816688313

Contamination ; Groundwater ; Groundwater pollution ; Nitrates ; Nitrogen ; Travel time ; Water quality ; Water treatment

Air Transportation:431 ; Highway Transportation:432 ; Railroad Transportation:433 ; Waterway Transportation:434 ; Groundwater:444.2 ; Water Treatment Techniques:445.1 ; Water Analysis:445.2 ; Water Pollution Sources:453.1 ; Chemical Products Generally:804 ; Inorganic Compounds:804.2 ; Accidents and Accident Prevention:914.1

ENVIRONMENT/ECOLOGY

Web of Science

1.Southern Univ Sci & Technol, Sch Environm Sci & Engn, State Environm Protect Key Lab Integrated Surface, Shenzhen, Peoples R China
2.Southern Univ Sci & Technol, Sch Environm Sci & Engn, Guangdong Prov Key Lab Soil & Groundwater Pollut C, Shenzhen, Peoples R China
3.Natl Univ Singapore, Dept Civil & Environm Engn, Singapore, Singapore
4.Univ Victoria, Dept Civil Engn, Victoria, BC, Canada
5.Univ Victoria, Sch Earth & Ocean Sci, Victoria, BC, Canada
6.Eastern Inst Technol, Ningbo, Peoples R China

Zhan, Yang,Guo, Zhilin,Ruzzante, Sacha,et al. Assessment of spatiotemporal risks for nationwide groundwater nitrate contamination[J]. SCIENCE OF THE TOTAL ENVIRONMENT,2024,947.

Zhan, Yang.,Guo, Zhilin.,Ruzzante, Sacha.,Gleeson, Tom.,Andrews, Charles B..,...&Zheng, Chunmiao.(2024).Assessment of spatiotemporal risks for nationwide groundwater nitrate contamination.SCIENCE OF THE TOTAL ENVIRONMENT,947.

Zhan, Yang,et al."Assessment of spatiotemporal risks for nationwide groundwater nitrate contamination".SCIENCE OF THE TOTAL ENVIRONMENT 947(2024).