Watershed science: Linking hydrological science with sustainable management of river basins

Abstract

Over the past decades, a number of water sciences and management programs have been developed to better understand and manage the water cycles at multiple temporal and spatial scales for various purposes, such as ecohydrology, global hydrology, sociohydrology, supply management, demand management, and integrated water resources management (IWRM). At the same time, rapid advancements have also been taking place in tracing, mapping, remote sensing, machine learning, and modelling technologies in hydrological research. Despite those programs and advancements, a water crisis is intensifying globally. The missing link is effective interactions between the hydrological research and water resource management to support implementation of the UN Sustainable Development Goals (SDGs) at multiple spatial scales. Since the watershed is the natural unit for water resources management, watershed science offers the potential to bridge this missing link. This study first reviews the advances in hydrological research and water resources management, and then discusses issues and challenges facing the global water community. Subsequently, it describes the core components of watershed science: (1) hydrological analysis; (2) water-operation policies; (3) governance; (4) management and feedback. The framework takes into account water availability, water uses, and water quality; explicitly focuses on the storage, fluxes, and quality of the hydrological cycle; defines appropriate local water resource thresholds through incorporating the planetary boundary framework; and identifies specific actionable measures for water resources management. It provides a complementary approach to the existing water management programs in addressing the current global water crisis and achieving the UN SDGs.

Patterns and Distributions of Urban Expansion in Global Watersheds

“…Therefore, quantifying urban expansion at the watershed scale could inform policymakers to manage these ecological and environmental issues and form sustainabilityoriented planning. Although it is very important to form urban sustainable planning at the watershed scale, it is still a challenge to collect data, mobilize public participation, achieve integration of decision-making across watersheds due to the mismatch between administrative boundaries and watershed boundaries(C. S. He & James, 2021).…”

A comprehensive review on coupled processes and mechanisms of soil-vegetation-hydrology, and recent research advances

“…A watershed is a basic unit and possesses all of the com-plexities of the land surface system (Cheng and Li, 2015;He and James, 2021), thereby making it the best unit for practicing Earth system science and studying the coupling mechanism of soil-vegetation-hydrological processes. Over the past ten years, several watershed observation systems with advanced observation techniques have become well established, such as the Danish Hydrological Observatory (HOBE), which was established in 2007 in a catchment in the western part of Denmark (Jensen and Illangasekare, 2011); and the watershed ecohydrological observation system (Hi-WATER) established through the "Integrated research on the eco-hydrological process of the Heihe River Basin" project supported by the National Science Foundation China since 2010 (hereinafter referred to as the "Heihe Plan").…”

“…( 5) Observation data of soil hydraulic properties in high-altitude mountainous areas are sparse, and the vertical distribution information of soil hydraulic properties in many areas is insufficient . ( 6) Building a multiscale monitoring network of hydrological processes and soil hydraulic properties is limited by cost (He and James, 2021).…”

Linking Critical Zone With Watershed Science: The Example of the Heihe River Basin

“…Building on multidisciplinary and interdisciplinary techniques, many new efforts have emerged over the past two decades to link traditional disciplines that were often studied in isolation to improve our understanding of the structure, functioning and evolution of the Earth system and its responses to climate change and anthropogenic disturbances and to promote the sustainable development of the Earth system (Cheng & Li, 2015; Steffen et al., 2020). Critical zone (CZ) science (Baldocchi et al., 2001; Lin, 2010; Sullivan et al., 2017) and watershed science (Cheng & Li, 2015; Cheng et al., 2014; He & James, 2021; Montanari et al., 2015) are two stark manifestations of such efforts, and they both represent integrated research pathways in Earth system science. Despite the significant advances made in CZ and watershed science in recent decades, grand challenges regarding the observation, modeling, and management of CZ and watershed systems remain.…”