However, inter-annual variability of semi-arid lands rainfall make directional trends in land cover change and causal chains hard to establish. The Serengeti-Mara Ecosystem offers a natural experiment with parallel and contrasting land-use zones superimposed on a 100,000 km2 rangeland where ecological, micro-economic and ethnic continuities make it possible to control for many confounding variables.

A core fortress conservation zone surrounded by a ring of buffer zones straddles the very different macro-economic and macro-political contexts demarcated by the Kenya/Tanzania border.

Analysis of extensive long-term data sets on wildlife and livestock, together with new in-depth remote sensing, demographic and socio-economic work show that rapid land cover change and wildlife decline are restricted to the Kenyan part of the system.

In the Masai Mara Ecosystem (Kenya), 60,000 ha of rangelands have been converted to mechanised agriculture and the total population of non-migratory wildlife species declined by 58% over the past 20 years. This study shows that, contrary to widely-held views, these changes are driven by markets and national land tenure policies, rather than by agro-pastoral population growth. Spread of mechanised agriculture on critical spatial locations underlies wildlife decline. This study was conducted with Professor Kathy Homewood and Suzzy Serneels.

About Eric F. Lambin
Eric F. Lambin is Professor and Chair of the Department of Geography at the University of Louvain, Louvain-la-Neuve, Belgium. He was previously Assistant Professor at Boston University and Expert for the European Commission at the Joint Research Center (Ispra).

He is the current Chair of the " Land-Use and Land-Cover Change " (LUCC) programme of the International Geosphere-Biosphere Programme (IGBP) and International Human Dimensions Programme on Global Environmental Change (IHDP).

The research interests of Eric Lambin cover the monitoring of land-cover changes and biomass burning by remote sensing, and the modelling of land-use changes and their ecological impacts.

Eric Lambin is working toward the integration of monitoring systems, fine scale surveys and integrated modelling to better understand processes of land-use change.