Scale-dependent patterns of deforestation in the Brazilian Amazon

Description

Tropical forests of the Amazon Basin are being rapidly converted to agricultural land uses and fallow land, resulting in accelerating rates of forest loss in one of the world's most biodiverse ecoregions. This process has been extensively described andmodelled, but as yet there has been no formal test ofhowthe spatial patterns of deforested and fragmented areas change with the spatial scale of forest clearings. It was hypothesised that different land-use practices are driving small and large clearings, with small-scale cultivators often creating small, irregularly shaped clearings and largescale ranchers and soy farmers creating larger, more regular-shaped clearings. To quantitatively test this hypothesis,Mandelbrot's theory of fractalswas applied to deforested areas in the Brazilian Amazon to test for scale-invariance in deforestation patterns. The spatial pattern of deforestation differed between small and large clearings,with the former creating more complex landscapes and with a threshold occurring at c. 1200 ha in area. As a consequence, the sizes and shapes of forest clearings, and hence the relative vulnerability of the remaining forest to edge, area and isolation effects, may differ systematically between landscapes with different deforestation drivers. Further tests of this hypothesis are needed to assess its efficacy in other tropical landscapes and geographical locations.

Type

Full Text Documents

View Original

https://repository.si.edu/handle/10088/18701

Source

Smithsonian Libraries

Creators

Ewers, Robert Mark Laurance, William F.

Keywords

Tropics Biology

Notes

doi: 10.1017/S0376892906003250 Citation: Ewers, Robert Mark and Laurance, William F. 2006. Scale-dependent patterns of deforestation in the Brazilian Amazon. Environmental Conservation, 33(3): 203-211. doi:10.1017/S0376892906003250

Dates

Year: 2006

Additional Info

Record ID: SILSRO_110818