Global forest cover mapping for the United Nations Food and Agriculture Organization forest resources assessment 2000 program

Z. Zhu; E. Waller

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USGS · 70025444

Global forest cover mapping for the United Nations Food and Agriculture Organization forest resources assessment 2000 program

Z. Zhu·E. Waller

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Abstract

Many countries periodically produce national reports on the status and changes of forest resources, using statistical surveys and spatial mapping of remotely sensed data. At the global level, the Food and Agriculture Organization (FAO) of the United Nations has conducted a Forest Resources Assessment (FRA) program every 10 yr since 1980, producing statistics and analysis that give a global synopsis of forest resources in the world. For the year 2000 of the FRA program (FRA2000), a global forest cover map was produced to provide spatial context to the extensive survey. The forest cover map, produced at the U.S. Geological Survey (USGS) EROS Data Center (EDC), has five classes: closed forest, open or fragmented forest, other wooded land, other land cover, and water. The first two forested classes at the global scale were delineated using combinations of temporal compositing, modified mixture analysis, geographic stratification, and other classification techniques. The remaining three FAO classes were derived primarily from the USGS global land cover characteristics database (Loveland et al. 1999). Validated on the basis of existing reference data sets, the map is estimated to be 77% accurate for the first four classes (no reference data were available for water), and 86% accurate for the forest and nonforest classification. The final map will be published as an insert to the FAO FRA2000 report.

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Z. Zhu, E. Waller. 2003. Global forest cover mapping for the United Nations Food and Agriculture Organization forest resources assessment 2000 program. https://pubs.usgs.gov/publication/70025444

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