Recent research published in the journal Hydrology and Earth System Sciences has shed light on the intricate dynamics of blue and green water resources in the Dongjiang River basin (DRB), a pivotal region for water supply in the Guangdong–Hong Kong–Macao Greater Bay Area of China. This study, led by X. Tan from the School of Geography and Planning at Sun Yat-sen University, highlights the pressing need for sustainable management practices that account for both blue water (BW) and green water (GW) resources, which are critical for ecosystem stability.
The findings reveal a nuanced picture of water resource dynamics in the DRB. While the study indicates a slow increase in BW and green water storage (GWS) at rates of 0.14 mm and 0.015 mm per year, respectively, it also notes a concerning decline in green water flow (GWF) at a rate of -0.21 mm per year. “The degree of BW and GW scarcity in DRB is relatively low, with over 80% of the region experiencing per capita water resources exceeding 1700 m³ per year,” Tan explained. This statistic underscores the potential for the region to manage its water resources effectively, but it also raises questions about the sustainability of such practices in the face of climate change.
The research underscores the significant impacts of climate change and land use changes on water resources. Notably, the study attributes 88% of changes in BW and GWF to climate change, suggesting that rising temperatures and shifting precipitation patterns are reshaping the hydrological landscape. Conversely, land use changes have been shown to increase GWF, illustrating the complex interplay between human activities and natural water cycles.
For stakeholders in the water, sanitation, and drainage sector, these insights are crucial. Understanding the factors that influence water availability and flow can guide the development of more effective water management strategies. “Our findings can help optimize the allocation of blue and green water resources, especially between upper and lower reach areas in DRB,” Tan noted, emphasizing the practical implications of the research.
As urbanization and development pressures continue to mount in the Greater Bay Area, the need for integrated water resource management becomes ever more critical. This research not only highlights the importance of considering both blue and green water in resource evaluations but also paves the way for future studies aimed at addressing the challenges posed by climate change. By fostering a deeper understanding of water resource dynamics, the findings may inspire innovative approaches to water management that balance ecological health with human needs.
The implications of this research extend beyond the academic realm, offering valuable insights for policymakers and industry leaders. As the water sector grapples with the dual challenges of climate change and rapid urbanization, studies like this can inform strategies that ensure sustainable water availability for generations to come. For further information on this research, visit School of Geography and Planning, Sun Yat-sen University.
