Xander Huggins

Topic

Groundwater-connected systems: A social-ecological framing, global data-driven applications, and sustainability implications

Department of Civil Engineering

Date & location

• Thursday, June 27, 2024

• 9:00 A.M.

• Engineering and Computer Science Building

• Room 660 and Virtual

Reviewers

Supervisory Committee

• Dr. Tom Gleeson, Department of Civil Engineering, University of Victoria (Supervisor)

• Dr. Tara Troy, Department of Civil Engineering, UVic (Member)

• Dr. Oliver Brandes, Centre for Global Studies, UVic (Outside Member)

• Dr. James Famiglietti, School of Sustainability, Arizona State University (Additional Member)  

External Examiner

• Dr. Ty Ferré, Department of Hydrology and Atmospheric Sciences, University of Arizona 

Chair of Oral Examination

• Dr. Kathy Sanford, Department of Curriculum and Instruction, UVic 

Abstract

Groundwater systems and groundwater science are both at critical moments characterized by rapid change. Human activities continue to transform the land surface and climate, pump groundwater at rates beyond physically renewable limits, and collectively attempt to govern and manage the resource. In recognition of this, groundwater science has broadened in recent decades to account for the interactions between people, ecosystems, Earth systems, and groundwater. Separately yet simultaneously, sustainability science has emerged as a problem-oriented field aimed at understanding interactions between social and natural systems within the contested and normative contexts of sustainability. In this dissertation, I work to better integrate leading sustainability science concepts and methods with groundwater science and demonstrate the utility of this approach through empirical global studies that combine large, multidimensional datasets with spatial data science methods. This work makes contributions under two overarching themes: to support a more comprehensive understanding of large-scale groundwater systems as social-ecological systems, and to explore possible uses of these insights in support of global groundwater sustainability.

The fundamental contribution of this study is the development of the groundwater-connected systems framing that provides a language, conceptual foundation, and pathway to consider groundwater systems as social-ecological systems (Paper I). This framing centers a relational understanding of groundwater where groundwater systems are explicitly considered on the basis of biophysical and socioeconomic interactions rather than on the basis of the resource’s hydrogeological characteristics or physiographic setting. I argue that this framing has useful implications across data collection, scientific investigations, education, and governance. The remainder of the dissertation begins to explore some of these opportunities through global-scale data-driven applications.

As all global analyses I conduct (Papers III-VI) are based on open access datasets, I first perform a scoping review of the existing open data landscape to study groundwater systems as social-ecological systems (Paper II). Over 130 datasets are identified and reviewed, and 40 unique datasets are used to generate findings across Papers III-VI.

I first apply the framing to construct a global classification and mapping of groundwater’s large scale (order of ~104 km2) biophysical and socioeconomic functions (Paper III). The resulting groundwaterscapes (n = 18) are landscape units that represent specific and broadly occurring configurations of groundwater functions across Earth systems, ecosystems, food systems, and water management systems. The groundwaterscapes are empirically derived using a sequential, self-organizing map algorithm, and provide a global perspective on groundwater systems that contrasts with existing groundwater resource maps as all large aquifer systems of the world are characterized by multiple groundwaterscapes. Groundwaterscapes offer a new lens and spatial tool to study groundwater dynamics, inform groundwater data collection priorities, and manage groundwater resources according to social-ecological context and consistent with leading sustainability science principles.

I subsequently investigate the groundwater sustainability implications of the groundwaterscapes. I do so by generating a complementary global classification of groundwater system risk types, informed by an Anthropocene risk framing. This typology of groundwater risk includes conventional risks such as groundwater storage loss and land use change in addition to unconventional, increasingly prioritized forms of risk such as gender development inequalities and hydro-political tension. Overlaying groundwaterscapes with groundwater risk types generates a collection of hundreds of unique groundwater sustainability challenges (Paper IV), providing the most comprehensive, social-ecological evaluation on the diversity of challenges that comprise the global groundwater crisis to date. The resulting groundwaterscape risk maps provide a tool to support solution transfer and network development among regions facing similar challenges.

I conclude by conducting two studies that demonstrate the broad applicability of the groundwater connected systems framing in contexts where groundwater considerations are often overlooked or omitted. In Paper V, I assess the social-ecological vulnerability of river basins to experience impacts from the linked threats of freshwater stress and freshwater storage loss, which embeds representation of groundwater storage trends, and identify a set of most vulnerable basins as hotspots for global prioritization. In Paper VI, I delineate the groundwater catchments of the world’s protected areas to highlight how groundwater flow can transmit human impacts occurring outside protected areas to ecosystems within protected area boundaries.