| PAGE MEASURES AND INDICATORS | DATA SOURCES AND COMMENTS |
| Global Forest Cover | FAO, 1997a. Area estimates based on national inventories, maps, some remote sensing data. IGBP, 1998, and DeFries et al., 2000. Both based on AVHRR 1-km resolution remote sensing data. |
| Historic Forest Loss | Matthews, 1983. Estimates
of historic forest loss supplemented with FAO data for post-1980 period. WCMC. Estimates of original forest cover for WRI’s Frontier Forests study (Bryant et al., 1997). |
| Recent Deforestation | FAO, 1997a. INPE and Pathfinder, remote sensing of Amazon basin. Holmes, 2000. Analysis of remote sensing data for Indonesia. |
| Degree of Naturalness | Bryant et al., 1997. Forest
intactness determined by presence of roads, other development and
expert opinion. FAO, FRA 2000 (unpublished). Forest naturalness determined by intensity of human intervention. Forest/Cropland Transition Zones GLCCD, 1998. Land cover classification scheme modified by WRI. Methodology may overstate degree of forest modification. |
| Fragmentation by Roads | CARPE, 1998. Roads database, updated by WRI for 6 Central African countries. |
| Forest Fires | Various remote sensing sources. Fires can be detected and monitored through thermal and midinfrared imaging during the day, and by the light they emit at night. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'Forests cover about
one quarter of the world’s land surface, excluding Greenland and
Antarctica. Just over half are found in developing countries. 'Global forest cover has been reduced by at least 20 percent since preagricultural times, possibly by 50 percent. Forest area has increased slightly since 1980 in industrial countries, but has declined by at least 10 percent in developing countries. ' Tropical deforestation rates are uncertain, but probably exceed 130,000 km2 per year. About 40 percent of forests are relatively undisturbed by human activity, though nearly half of these are likely to be developed soon. 'Nearly all forests in Europe and the United States are under some degree of management. 'Mixed forest/agriculture zones are spreading rapidlt a the edges of formerly intact forest, but this form of land use change is often not recorded as forest conversion. 'Roads are a useful proxy indicator of habitat fragmentation and degradation. The world’s expanding road network is opening up remote forests to logging, mining, and pioneer settlement. Roads also increase hunting and poaching. 'The area burned by natural forest fires is now insignificant in comparison with human-initiated fires. Tropical forest fires have increased in area and intensity in recent years, because of drought, clearance for agriculture, and land tenure disputes. |
'National level forest maps are
often outdated and forest inventories unreliable in developing
countries. Global estimates of forest area are complicated by different
definitions of forest land and deforestation. 'Remote sensing data expected to become available in the next few years should improve the information base. Priority information needs include more frequent satellite surveys and higher sampling rates to catch nonrandomly distributed deforestation. Ground truthing will remain important to verify maps generated by remote sensing data. 'Knowledge of forest biological condition lags behind that for forest extent. Classification schemes for forest condition are simplistic but still difficult to implement. There is a need for agreement on what constitutes good condition in different forest types, managed for different purposes, and for indicators to monitor change, applicable at the national and subnational levels. 'Data on mixed forest/cropland land cover are poor. Vegetation classification schemes based on thresholds and discrete boundaries work against fine scale interpretation of land use data. There is a need for higher resolution remote sensing data and information on biomass quantities. 'The global roads dataset is out of date. Information is poor in developing countries where the road network is expanding fastest. Updated digitized information on existing and planned roads would be useful. ' There is an urgent need is to improve national and international ability to estimate forest fire potential and to detect and monitor wildfires while they are still small enough to control. A number of satellite systems have been evaluated for fire detection, including AVHRR, the Defense Meteorological Satellite Program (DMSP) Operational Linescan System sensor, and the NOAA Geostationary Operational Environmental Satellite (GOES) sensor. At present all three systems, each with unique characteristics, are required to provide the best results. |
| PAGE MEASURES AND INDICATORS | DATA SOURCES AND COMMENTS |
| Production Volume | FAOSTAT. On-line database
(global). Generally good data on production volume and value, although some estimation involved for Africa. |
| Availability of Productive Forest Land | FAO, 1998. Area of economically
available forest will change with fiber prices. Harvesting Intensity FAO, 1998. Data incomplete for many developing countries. |
| Plantation Area | FAO. Pandey, 1997 and Brown,
1999. Global coverage but data uncertain for many countries |
| Plantation Productivity | FAO. Pandey, 1997 and Brown, 1999. Good yield data available but scattered. |
| Tree Diameter Size | Haynes et al., 1995. Case study of United States production forests. |
| Impacts of Logging on Biodiversity | Survey of local studies in tropical countries of impacts on birds, butterflies and moths. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'Global industrial
fiber production totals 1.5 billion cubic meters. Production has risen
by 50 percent since 1960 and is expected to rise by between 20 and 50
percent by 2020. Nearly 80 percent of fiber production today comes from
primary and secondary-growth forests. 'Less than half of global forest area is defined by FAO as currently available for fiber production. The remainder is restricted either by current market conditions or by legal protection. Production is concentrated in North America, Europe, and Asia. The greatest reserves of currently unexploited mature trees exist in Canada, Russia, and Brazil. 'Only the United States and Western European countries currently harvest less wood from available forest land than regrows annually. Canada, Russia, Central and Eastern Europe, and most developing countries harvest above replacement rates in their available forest areas. 'Industrial wood plantations now supply just over 20 percent of fiber production. This share is expected to increase in future, but increased production from plantations will not necessarily decrease harvest rates in natural forests. 'Well-managed industrial wood plantations, especially those in the Southern Hemisphere, are capable of yields 5, 10, or even 50 times greater than those obtained from natural forests. However, some plantations in developing countries appear to have high planting failure rates. 'Production forests which have been managed for decades tend to become more uniform in structure; their trees, on average, are younger and smaller in size than in unmanaged forests. 'Immediate local-level impacts of logging on tropical forest biodiversity can be severe, but many groups of species appear to recover over time. Different taxa vary in their requirement for large, intact areas of undisturbed forest. |
Data on production volume and
value are generally good, although estimates are involved for some
developing countries. Information needs include spatial information at
the subnational level on timber harvests, national-level data on the
share of production from primary and secondary forest, and better
monitoring of the extent and location of illegal logging. 'More economic analysis is required of the relationship between fiber prices, wood industry technologies, and the likely balance of supply from plantations and natural forests. 'Good forest inventory information is available for most industrial countries, but is incomplete for developing countries, where better information on growth rates, age and diameter class, harvest rates, tree mortality and planting, and methods of harvesting is needed at the national and subnational levels. 'Reporting on plantation establishment and success rates is uneven in some developing countries. Definitional difficulties among seminatural and plantation forests obscure plantation extent in industrial countries. Better information is needed on the amount and types of land converted to plantations (closed or open forest, degraded land, other) each year. Information on reported and net plantation area should distinguish between failed and harvested plantations. 'Good yield data are available for individual plantations but usually not at national level. High yields are recorded on some plantations and in field trials but it is not clear how far these have been translated to the field. More information and indicators are needed on long-term yields and biological and management parameters of plantations. 'The impacts of logging on biodiversity are still poorly understood. Information is needed on impacts on species other than birds, moths, and butterflies, especially invertebrates. More studies are needed of impacts in nontropical forests. There is an urgent need for agreement on relatively simple biodiversity indicators that can be monitored as logging operations progress. |
| PAGE MEASURES AND INDICATORS | DATA SOURCES AND COMMENTS |
| Production Volume | FAOSTAT. On-line database (global). Mostly modeled data. IEA, 1996. Combustible Renewables and Waste Database (global). Data based on questionnaires and local databases. |
| Wood Energy Share of
National Final Energy Consumption |
IEA, 1996. Combustible Renewables and Waste Database (global). Good disaggregation of biomass fuels but time series not available. |
| Sources of Woodfuel | RWEDP, 1997a. Regional studies in 16 Asian countries. Few systematic data on woodfuel collection or consumption are available. |
| Woodfuel Scarcity | CIESIN, 2000. New estimate of global population density. DeFries et al., 2000. 1-km dataset of percentage tree cover (global). Areas of high population density, high dependence on woodfuel and low tree cover may be at risk of scarcity. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'About 1.8 billion
cubic meters of wood are burned directly as fuel each year, equivalent
to over half the total roundwood harvest. Production and consumption
are concentrated in low-income countries. 'Woodfuels account for about 15 percent on average of primary energy supply in developing countries and up to 80 percent of total energy in some countries in Sub-Saharan Africa and Asia. 'In the industrialized countries, burning of industrial wood residues, as well as wood harvested directly for fuel, means that between 30 and 50 percent of total wood removed from forests is ultimately used for energy, but wood contributes only about 3 percent of total energy supply throughout the OECD region. 'Forests appear to supply only about one third of woodfuels. The balance is obtained from other sources, including woodlands, roadsides, backyards, community woodlots, and wood industry residues. 'Shortages of woodfuel exist at the local level but, at the global level, forecasts of scarcity have probably been exaggerated. Poor data mean that the likelihood of a future woodfuel crisis cannot be accurately assessed. Scarcity hotspots appear concentrated in areas of high population density, low tree cover, and low income. |
'Data on woodfuel production and
consumption in most developing countries are limited, unreliable, and
largely dependent on modeled estimates. Wood energy is generally
accorded low priority in national energy planning, despite its major
role in energy supply. 'Information is needed at the subnational and national levels on the sources of woodfuel and household and industrial consumption to develop better estimates of demand and integrate woodfuels into national energy planning. 'Development of the FAO Wood Energy Database can be expected to improve knowledge of nonforest sources of wood fuels and patterns of supply and demand. Information on the ecological impacts of woodfuel collection is patchy. 'More use of remote sensing data and and the development of low-cost sampling and analysis techniques could help to determine biomass balances associated with woodfuel collection. Such data would be relevant to both energy planning and environmental analysis. |
| PAGE MEASURES AND INDICATORS | DATA SOURCES AND COMMENTS |
| Global 200 Ecoregions | Olson and Dinerstein, 1998.
Categorization scheme based on broad environmental characteristics and expert opinion. |
| Endemic Bird Areas | Stattersfield et al., 1998.
Global sites identified through field observation and expert judgment. Centers of Plant Diversity WWF and IUCN, 1994. Global sites identified through field observation and expert judgment. Protected Forest Areas WCMC, 1999. Global database, based on IUCN management categories I-V. |
| Threatened Trees | Oldfield et al., 1998. Global list developed through field observation and expert judgment. |
| Threatened Birds | Wege and Long, 1995. Key Areas in Latin America mapped through field observation and expert judgment. |
| Non-Native Plant Species (% of total) | Ricketts et al., 1997. Data compiled from county level observation in North America. Data do not distinguish between benign non-natives and harmful invasives. |
| Projected Extinction Rates | Various studies and theoretical
estimates, most based on data from tropical rainforest areas and tropical islands. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'WWF has identified
more than 200 ecoregions as outstanding
representatives of the world’s diverse ecoystems and, therefore,
priority areas for conservation. Forest types account for two thirds of
all terrestrial ecoregions. 'Nearly three quarters of the world’s threatened bird species have restricted breeding ranges and remain confined to relatively small areas. Endemic bird areas (EBAs) encompass the range of the majority of these birds and more than 80 percent of EBAs are found in forests. 'Centers of plant diversity have been identified as conservation priority areas, rich in plant diversity or endemism. More than three quarters of the centers are found in forests. 'Less than 8 percent of global forest area is legally protected. Legal safeguards appear ineffective against logging, poaching, and other forms of development in many countries. 'Nearly 9 percent of trees globally are now at some risk of extinction. The leading threat is logging, followed by conversion to agriculture and expansion of human settlements. 'One quarter of the world’s threatened birds occur in the non-Caribbean neotropical region. BirdLife International has identified nearly 600 sites that are key to the survival of these species and more than 80 percent of the sites occur in forests. 'Forests near human settlement or transportation routes have high concentrations of nonnative species, which have been introduced deliberately or accidentally. Most are benign, but some invasive plants and insect pests have done extensive damage to both production and amenity forests. 'Moderate estimates of future species extinction rates in tropical forests range from 1 to 5 percent per decade. However, such estimates have high and largely unknown levels of uncertainty, because of both the uncertainty of the underlying data and the assumptions on which they are based. |
'Information on biodiversity is
not currently adequate as a basis for
forest management planning decisions or land use decisions at the
landscape level. 'Detailed field-based biodiversity surveying over wide areas is not economically feasible, even in highincome countries. There is an urgent need for local and regional biodiversity management tools that can be developed from remote sensing and GIS. 'Other priority needs include better baseline information at the level of ecosystem types, species, and genetic resources, and agreed indicators of biodiversity condition, including habitat heterogeneity monitored over time that can be used to assess the impacts of habitat loss and modification. 'More information is urgently needed on the current status of protected areas and the effectiveness of logging bans or other conservation measures within these areas. |
| PAGE INDICATOR | DATA SOURCES AND COMMENTS |
| Total Carbon Stored in Forests (tons) | Olson et al., 1983. Global
estimates of carbon in above- and below-ground live vegetation,
modified by EDC and WRI (USGS/EDC, 1999). Soil carbon estimates based
on ISRIC-WISE global dataset of derived soil properties (Batjes, 1996; Batjes and Bridges, 1994) and FAO digital soil map of the world (FAO, 1995). All datasets are coarse but globally consistent. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'Forest soils and
vegetation store about 40 percent of all carbon in the terrestrial
biosphere, more than any other ecosystem. 'Globally, more carbon is stored in forest soils than in forest vegetation. Boreal forests are especially rich in soil carbon, while tropical forests probably store more in their vegetation. 'Regrowth of forests in the Northern Hemisphere may account in part for the increasing terrestrial sink that absorbs some of the carbon dioxide emissions released by fossil fuel combustion. However, land use change, primarily tropical deforestation, currently releases an estimated 1.6 billion tons of carbon to the atmosphere each year, equivalent to 25 percent of emissions from fossil fuel combustion. 'Globally, deforestation far exceeds regrowth. The world’s forests are currently a net source of carbon. |
'Uncertainty still exists over
rates of carbon sequestration, carbon
stores, and the size and location of the terrestrial “missing carbon
sink.” 'Improving information is available from local and regional studies on carbon stores in different vegetation types but a variety of measurement methodologies used yields conflicting results. 'Many more soil samples are required globally for more accurate determination of soil carbon stores. 'Better information is needed on carbon sequestration rates at the site-specific level to provide an adequate basis for calculating carbon offsets achievable through afforestation programs under climate mitigation programs. |
| PAGE MEASURES AND INDICATORS | DATA SOURCES AND COMMENTS |
| Forest Cover in Major Watersheds (% Remaining) | Revenga et al., 1998. Global
survey of 145 major and secondary watersheds. FAO, 1993. Estimates of deforestation rates in montane areas. |
| Vegetation Cover and Soil Erosion | Survey of local studies, mostly in tropical and subtropical region. |
| CONDITIONS AND TRENDS | INFORMATION QUALITY AND NEEDS |
| 'One third of the
world’s major watersheds have lost more than 75 percent of their
original forest cover. 'Tropical montane forests, which are often located in the upper reaches of watersheds, are disappearing faster than any other tropical forest type. 'Deforestation is associated with alteration of stream flow quantity, quality and regularity, although links to major floods are more complicated than sometimes portrayed. 'Ground cover vegetation appears to be more important than tree cover in preventing erosion, but erosion rates under shifting cultivation are ten times higher than in natural forest. Erosion rates can be 100 times higher in plantations where weeds and leaf litter are removed. |
'The relationships between
forest cover, forest type, and hydrological regimes are still
inadequately understood. 'Information is most valuable at the site-specific and river basin levels, which can provide a sound basis for land use planning decisions affecting watersheds and downstream populations. 'Information is needed on the evaporative characteristics of different tree species and soil combinations, background and human-induced rates of soil erosion, and sedimentation rates and flooding incidence. 'Site-specific models are required to predict the impacts of afforestation or deforestation in catchment areas. |