Pilot analysis of global ecosystems: Forest ecosystems

The PAGE reports analyze quantitative and qualitative information and develops indicators of the condition of the world’s freshwater, coastal, forests, grassland and agroecosystems. The condition is defined as the current and future capacity of the systems to continue providing the full range of goods and services needed or valued by humans.

The PAGE: Forests ecosystems examines the spatial extent of forests and the degree of human modifications on their extent and structure over time. It also looks at measures of condition concerning five important goods and services: industrial roundwood and woodfuel production, biodiversity, carbon storage and sequestration, and watershed protection. The choice of goods and services was determined partly in consultation with forestry experts in many countries and partly by data availability.

Results of the analysis show that global forest cover has been reduced by between 20 and 50 percent since preagricultural times.

• Nearly all forests in Europe and the United States are under management and support reduced levels of biodiversity.
• Loss and degradation of tropical forest is more severe than official estimates imply because zones of mixed forest and agriculture are spreading rapidly at the borders of formerly intact forests; these zones usually support enough trees to classify as forest although their capacity to provide the full range of forest goods and services may be greatly reduced.
• The world’s growing road network poses a major threat to forest condition because they provide access for development and increase hunting and poaching.
• Logging continues to degrade mature forests, despite the growing importance of wood plantations as a source of supply.
• Demand for wood and pulp is growing rapidly, and could lead to exploitation of currently remote forests, especially in Siberia, Central Africa and the Amazon basin.

GIS Data Sets

• Land use GIS data for Ban Lung Village, Cambodia. ArcInfo Coverage. This data can be displayed in Arcview 3x. Arcview 8x, or Arc Explorer software. UTM Zone 48 Projection.
  Year 1953 (ZIP archive, 143 Kb)
  Year 1996 (ZIP archive, 491 Kb)

• Agroecosystem cropland mosaics for Africa (ZIP archive, 2.3 Mb). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Interrupted Goodes Homolosine Projection.

• Central Africa forest fragmentation by roads (includes roads). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Lambert Equal-Area Azimuthal projection, Central Meridian 20, reference latitude 5.
  Including roads (ZIP archive, 1.0 Mb)
  Excluding roads (ZIP archive, 996 Kb)

• Global carbon storage in soils GIS dataset (ZIP archive, 719 Kb). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Interrupted Goodes Homolosine projection.

• Share of woodfuels in global national consumption (ZIP archive, 2.8 Mb). GIS Shapefile format. This data can be displayed in Arcview 3x. Arcview 8x, or Arc Explorer software. Geographic projection.

• Global storage in above- and below-ground live vegetation and soils (ZIP archive, 3.9 Mb). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Interrupted Goodes Homolosine projection.

• Population density and tree cover GIS data set (ZIP archive, 3.8 Mb). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Geographic Projection.

• Global tree cover GIS dataset (ZIP archive, 50.5 Mb). ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Interrupted Goodes Homolosine Projection.

• Africa percent tree cover (ZIP archive, 3.7 Mb). Reclassed into 4 classes where values 0 = oceans, 10 = GT 60 % cover, 20 = 30-60% cover, 30 = 10-30% cover, and 40 = LT 10 % cover. ArcInfo raster Grid format. This data can be displayed in Arcview 3x. Arcview 8x, with the Spatial Analyst Extension. Interrupted Goodes Homolosine Projection.

• High range values for global carbon storage in above- and below-ground live vegetation (ZIP archive, 3.1 Mb). High range values for global carbon storage in above- and below-ground live vegetation.