Abstract
The state and dynamics of river chemistry are influenced by both anthropogenic and natural catchment characteristics. However, understanding key controls on catchment mean concentrations and export patterns comprehensively across a wide range of climate zones is still lacking, as most of this research is focused on temperate regions. In this study, we investigate the catchment controls on mean concentrations and export patterns (concentration–discharge relationship, C–Q slope) of river chemistry, using a long-term data set of up to 507 sites spanning five climate zones (i.e., arid, Mediterranean, temperate, subtropical, tropical) across the Australian continent. We use Bayesian model averaging (BMA) and hierarchical modeling (BHM) approaches to predict the mean concentrations and export patterns and compare the relative importance of 26 catchment characteristics (e.g., topography, climate, land use, land cover, soil properties and hydrology). Our results demonstrate that mean concentrations result from the interaction of catchment indicators and anthropogenic factors (i.e., land use, topography and soil), while export patterns are influenced by topography. We also found that incorporating the effects of climate zones in a BHM framework improved the predictability of both mean concentrations and C–Q slopes, suggesting the importance of climatic controls on hydrological and biogeochemical processes. Our study provides insights into the contrasting effects of catchment controls across different climate zones. Investigating those controls can inform sustainable water quality management strategies that consider the potential changes in river chemistry state and export behavior.
| Original language | English |
|---|---|
| Article number | e2022WR032365 |
| Pages (from-to) | 1-26 |
| Number of pages | 26 |
| Journal | Water Resources Research |
| Volume | 58 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - Dec 2022 |
Bibliographical note
Funding Information:This work is funded by National Natural Science Foundation China (41807433). We would like to acknowledge that all water quality and flow data assembled in this study were accessed from the monitoring data collected by the individual state and territory agencies across Australia. We were assisted by: Christine Webb (The Department of Water and Environmental Regulation, Western Australia), Erinna Colton and Ashley Webb (WaterNSW, New South Wales), Julia Schult, Steve Tickell and Yuchun Chou (Department of Environment, Parks and Water Security, Northern Territory), David Waters, Belinda Thomson, Ryan Turner, Rae Huggins (Department of Resources and Department of Environment and Science, Queensland), Matt Gibbs (Department of for Water and Environment, South Australia), Bryce Graham (Department of Primary Industries, Parks, Water and Environment, Tasmania), Paul Wilson (Department of Land, Water and Planning, Victoria). We also would like to thank Professor Andrew Western from the University of Melbourne and Ms. Natalie Kho from Monash University for their assistance in guiding this work and in data processing. Clément Duvert thanks Charles Darwin University for supporting a research visit to the University of Melbourne in March 2020. We also acknowledge the Traditional Owners who were the first custodians of Australian waterways. The comments of three anonymous reviewers greatly helped to improve our manuscript.
Funding Information:
This work is funded by National Natural Science Foundation China (41807433). We would like to acknowledge that all water quality and flow data assembled in this study were accessed from the monitoring data collected by the individual state and territory agencies across Australia. We were assisted by: Christine Webb (The Department of Water and Environmental Regulation, Western Australia), Erinna Colton and Ashley Webb (WaterNSW, New South Wales), Julia Schult, Steve Tickell and Yuchun Chou (Department of Environment, Parks and Water Security, Northern Territory), David Waters, Belinda Thomson, Ryan Turner, Rae Huggins (Department of Resources and Department of Environment and Science, Queensland), Matt Gibbs (Department of for Water and Environment, South Australia), Bryce Graham (Department of Primary Industries, Parks, Water and Environment, Tasmania), Paul Wilson (Department of Land, Water and Planning, Victoria). We also would like to thank Professor Andrew Western from the University of Melbourne and Ms. Natalie Kho from Monash University for their assistance in guiding this work and in data processing. Clément Duvert thanks Charles Darwin University for supporting a research visit to the University of Melbourne in March 2020. We also acknowledge the Traditional Owners who were the first custodians of Australian waterways. The comments of three anonymous reviewers greatly helped to improve our manuscript.
Publisher Copyright:
© 2022. The Authors.
