Stephen J. Walsh, Ph.D., Lyle V. Jones Distinguished Professor, Geography
My research examines human-environment interactions, particularly, as the interactions relate to understanding the multidimensional drivers of land cover/land use change, island sustainability, and scenarios of change. In addition, I develop and use a suite of measurement and analysis methods that integrate data across space-time scales, assess spatial structures of people and environment through remote sensing approaches, and integrate survey, census, and geospatial data through geographic information systems and spatial simulation models, particularly, agent-based models, dynamic systems models, and econometric models.
Walsh's research examines population-environment interactions within the context of coupled human-natural systems in the Northern Ecuadorian Amazon, and in the Galapagos Islands of Ecuador. His population research explores questions about social and ecological vulnerability, resilience, and sustainability in diverse settings. Through his collaborations with CPC Fellows Bilsborrow, Entwisle, and Rindfuss; and several doctoral trainees, Walsh has described various challenges to mapping, measuring, and modeling population-environment interactions, including linking population and environment; examining social-ecological patterns and dynamics; characterizing agricultural frontiers and island settings, land use dynamics, and human-environment interactions and the drivers of change; and modeling coupled human-natural systems, pattern-process relationships, and population-environment interactions in multiple settings and contexts. Of particular interest to Walsh are new developments in complexity theory and Agent-Based Models (a type of micro-simulation), Dynamic Systems Models, and Integrated Assessment Models that make it possible to specify and explore feedbacks in population-environment relationships through process understanding.
Walsh will focus on (1) Human-Environment Interactions, i.e., relationships between environment and population with particular emphasis on the linkages between deforestation, agro-forestry systems, urbanization, tourism, population demographics and socio-economic patterns, household livelihoods, land use/land cover change, social-ecological vulnerability, and island sustainability; (2) Coupled Human-Natural Systems, i.e., the integration of people, place, and environment considered through the lens of Complexity Theory in which nonlinear relationships, feedback mechanism, emergent behavior, and complex adaptive systems are examined using multi-agent based models and spatial and statistical analyses, with the general goal to understand pattern-process relations within the context of a dynamic environment, evolving characteristics of multiple agents, interaction mechanisms, rules of behavior, and scenarios of change; and (3) Geographic Methods, i.e., remote sensing, GIS & spatial analysis and modeling approaches within the context of landscape characterization and representation of social and biophysical systems with particular emphasis on the use of spatial models for landscape characterization and simulation of the drivers of land use/land cover change.