Magnitude of Habitat Fragmentation by Terrestrial Ecoregion

Magnitude of habitat fragmentation indicated by largest patch size, by terrestrial ecoregion.

We considered agriculture, urban infrastructure, roads, and railroads as “fragmenting” features to the landscape and areas not converted to agriculture, urban infrastructure, roads, or railroads as “nonfragmented” terrestrial landscape patches. We used input spatial data from JRC’s GLC 2000 (2003), CIESIN et al. (2004), Defense Mapping Agency (1992), and South American Conservation Region (2005). To produce the data, we constructed a global map grid of fragmenting features (Mollweide projection, based on the WGS 1984 datum; 1 km2 resolution); this grid was then combined with the GLC 2000, adding a new “fragmenting features” class to the GLC 2000 map. We then extracted a window around the area of each ecoregion in a way that avoided truncating landscape patches with the ecoregion boundary, and measured landscape fragmentation characteristics using Fragstats (McGarigal et al. 2002). The map shows one of these characteristics: the largest patch size by ecoregion.

These data were derived by The Nature Conservancy, and were displayed in a map published in The Atlas of Global Conservation (Hoekstra et al., University of California Press, 2010). More information at http://nature.org/atlas.

The primary resources we used to develop this map were the following:
CIESIN (Center for International Earth Science Information Network), IFPRI (International Food Policy Research Institute), the World Bank, and CIAT (Centro Internacional de Agricultura Tropical). 2004. Global Rural-Urban Mapping Project (GRUMP): Urban Extents, Columbia University Palisades, New York, USA. Available at http://sedac.ciesin.columbia.edu/gpw/. Digital media.

Defense Mapping Agency. 1992. Digital Chart of the World [4 CDs]. Updated 1996. Fairfax, VA: Author.

Joint Research Centre of the European Commission (JRC). 2003. GLC 2000: Global Land Cover Mapping for the Year 2000. Ispra, Italy: European Commission Joint Research Centre, Institute for Environment and Sustainability. Available at www-tem.jrc.it/glc2000. Digital media.

McGarigal, K., S. A. Cushman, M. C. Neel, and E. Ene. 2002. FRAGSTATS: Spatial Pattern Analysis Program for Categorical Maps. Amherst: University of Massachusetts. Available at www.umass.edu/landeco/research/fragstats/fragstats.html.

South American Conservation Region. 2005. Vías de Sur America. Geographic Information System data set. The Nature Conservancy, Arlington, Virginia, USA.