Biocomplexity, Spatial Scale and Fragmentation: Implications for Arid and Semi-Arid Ecosystems

This proposal argues that spatial complexity of vegetation plays a central role in the structure and function of temporally variable, arid and semi-arid ecosystems. Complexity results from movement-mediated linking of less complex spatial units by herbivores and humans into spatially extensive, complex systems. But modern human land use and land tenure systems tend to deplete spatial biocomplexity through fragmentation of ecosystems into isolated and simplified units. Ecosystem fragmentation is often justified as a means of economic intensification in the neo-classical framework, but in fact, it costs money to replace the natural capital lost through fragmentation. As a result of fragmentation, many of the worlds arid and semi-arid grazed ecosystems are dysfunctional to varying degrees.

The goal of this project is to demonstrate the importance of spatial complexity, the costs of fragmentation, and to identify options for sustainability at sites around the world by linking ecological and socio-economic research, and in the process, create an international network of scientists addressing these issues. The project focuses on 21 sites in nine countries on four continents. The interdisciplinary scientific team includes ecologists, anthropologists, economists, and political scientists. The project will include case study syntheses, field-based investigations, and model experiments and analyses. The project is expected to promote a higher level of understanding of spatial-temporal distribution of complexity, its importance in grazed systems, why and how complexity is reduced through fragmentation, and what this means for ecosystems and economic activities.

Lead Investigator: 
Other Investigator(s): 
nine countries, four continents
Spatial Scope: 
global synthesis
Natural System: 
arid, semi-arid grasslands
Human System: 
land use