Capturing human-environment interactions in forest ecosystems with mathematical and computational models

Abstract: On shorter timescales, it is possible to treat human impacts on ecosystems as fixed, and likewise to treat ecosystem impacts on humans as fixed. However, on longer timescales, both ecosystems and human systems respond to one another, forming a single, fully coupled human-environment system (HESs). In this talk I will provide an overview of theoretical modelling of coupled human-environment systems, including a discussion of the challenges in modelling human behaviour. I will also describe two recent HES models concerning the effectiveness of forest conservation incentives in the face of human-environment feedbacks, in the context of (1) firewood movement restrictions for preventing the spread of forest pest infestations in Canada, and (2) forest conservation incentives and penalties to landowners to promote afforestation in Brazil. We find that social processes can fundamentally alter ecosystem dynamics. For instance, introducing human-environment feedback can increase the number of stable system states. It can also mitigate conservation strategies, by reducing their effectiveness through negative feedbacks, or by causing instabilities in the form of oscillations. We conclude that HES models can help us entertain possibilities that we might not otherwise have thought of, and in the future may also have some predictive power. Thus, human-environment feedbacks should be more extensively analyzed during the design and implementation of forest conservation policies. This work is conducted jointly with Madhur Anand.

Bio: Professor Chris Bauch is a University Research Chair in the Department of Applied Mathematics at the University of Waterloo, Canada. His research group develops mathematical and computational models of population dynamics in ecology and epidemiology. His particular emphasis is on understanding coupled human-environment systems. Study systems include forest-grassland ecosystem mosaics, forest pest infestations, and vaccine scares, among others. His work has reached a wide public audience through the media, having been covered in The New York Times, Scientific American, USA Today, BBC News and other sources. His research has been published in journals such as Science and Proceedings of the National Academy of the USA, and has been funded by organizations such as the World Health Organization, the United States Food and Drug Administration, and the Bill and Melinda Gates Foundation. Further details can be found at www.math.uwaterloo.ca/~cbauch