| Sumario: | Most studies of vegetation in African savannas have adopted reductionist approaches to research, mostly by looking at only “natural” or “anthropogenic” spaces in focal landscapes. Few have considered how social and biophysical factors interact to create vegetation patterns across landscapes. More holistic understanding of pattern-process relationships across savanna landscapes as wholes is needed to manage the ecological connections of global and local change. To understand how process interactions create vegetation patterns in a savanna landscape, I sampled vegetation in 217 sites in southwestern Mali, where conditions are similar to many parts of West Africa. For each site, I collected site-specific data on several biophysical factors as well as histories of settlement or cultivation, based on ethnographic interviews. Hierarchical clustering, indicator species analysis, multiresponse permutation procedures, and nonmetric multidimensional scaling revealed patterns of floristic variation across the landscape that related to patterns of biophysical variation and disturbance history. The results show complexity in terms of both pattern and process. Patterns evident at different scales of organization are not necessarily congruent, and vegetation heterogeneity is greater than expected based on any subset of biophysical or social processes. Soil moisture, bedrock lithology, and disturbance history are particularly important in shaping vegetation characteristics. Complex patterns arise because vegetation shows three different responses to settlement and cultivation — turnover, homogenization, and resilience — with actual outcomes that depend on site-specific biophysical and social conditions. This research shows that research epistemology can shape physical geographic knowledge and that savanna landscapes must be seen as entities with characteristics that are maintained through human-environment interaction. Reprinted by permission of the publisher.
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