Forests cover almost 30% of the Earth’s terrestrial surface (FAO 2006). They harbor much of the world’s biodiversity, provide invaluable ecosystem services such as the production of atmospheric oxygen, and are a major productive resource for commodities ranging from traditional medicines and food to wood and paper. In certain regions, forested areas are being cleared at high rates. The highest rates of deforestation are occurring in the tropics of Southeast Asia, South America, and Africa. Forest planting, the natural expansion of forests, and landscape restoration are only partially offsetting these losses. Most recently, forests have taken on a critical role in discussions about climate change. Because forests store carbon dioxide in their biomass and soils, current deforestation trends are now contributing to approximately one fifth of total annual global carbon emissions (IPCC, 2007). Forest management policies must balance environmental concerns with commercial activities. One of the major barriers to establishing sustainable forest practices is the lack of long-term monitoring systems to regularly assess the performance and condition of forests. Even when the scope is limited only to commercial wood production, experts have struggled for many decades to develop cost-effective methods for measuring forest resources and products. The forestry metric included in the 2008 EPI is meant to be a starting point for measuring forest management on an international scale. Its inclusion highlights the importance of forests as a global resource and as well as the need for more robust international monitoring efforts.
Currently only 10% of the world’s forested area has been assessed by field-based National Forest Inventories, which are the primary source of national-level forest data (Holmgren 2007). One of the standard measures of existing forest conditions is the calculation of “growing stock”. This value is defined as a forest’s standing volume of wood biomass of trees above a certain size (thus excluding the youngest and smallest trees).
The only source of country-by-country data for growing stock is the Global Forest Resources Assessment (GFRA), most recently conducted in 2005 (FAO 2006a). Even though other sources of regional growing stock data exist, the advantage of the GFRA is that it provides a consistent reporting format across countries and is recognized as the main global reporting process. It also provides the only global datasets for the value of both wood and non-wood forest products. No global data sets exist for the value of ecosystem services provided by forests. Within the GFRA, there are significant variations in data quality between countries due to differences in data collection methodology or differences in the frequency of measurements. One of the fundamental inconsistencies is that countries are allowed to choose what they consider to be a minimum tree size for inclusion in the growing stock measure. Countries also individually establish the height to which they calculate the volume and branch size they wish to include in this metric. Beyond these inconsistencies, some countries simply lack the resources to conduct regular forest surveys. In fact, only around 50 nations have field-based inventories; the rest use satellite data or expert estimates. Despite the shortcomings of the data, the “growing stock” calculation of the GFRA is the only global dataset of reasonable quality to include in the 2008 EPI forest indicator.
Though there are many areas of concern when measuring the sustainability of forest management, the core issue is whether forests are being cut at a faster rate than they are regrowing. There are many different potential variables that could go into an indicator measuring forest sustainability. The United Nations Forum on Forests has outlined seven such principal areas of concern, which are also the key foci in the UN Food and Agriculture Organization’s Global Forest Resources Assessment (GFRA). A much more extensive list of over 400 sustainability variables, crafted as an extension of the Pan-European Criteria and Indicators for Sustainable Forest Management, is used as a foundation by the Ministerial Conference on the Protection of Forests in Europe (MCPFE, 2007).
While capturing these variables in a forest management indicator would be ideal, only a handful of countries have sufficiently developed forest monitoring systems to produce meaningful reports on these criteria. As such, they are currently not usable for the purposes of a global, standardized assessment of performance. Having considered the limitations of global datasets, the only metric consistently available for reliable use in the 2008 EPI is the GFRA growing stock measure. Therefore the environmental performance of a country’s forestry sector is measured by a change in growing stock, represented as the Growing Stock Change indicator.
Over half of the countries ranked in the EPI achieve or exceed the target of zero change in growing stock. This is consistent with the fact that deforestation is a regional rather than global trend. While high rates of deforestation exist in many tropical countries, total forest volume is increasing globally. Nevertheless, the final scores do not highlight all the nations with known deforestation problems.
Island nations and major timber suppliers of tropical hardwoods are expected to score poorly. Consistent with this expectation, Indonesia is in fact at the very bottom of the list, sharing a score of ‘0’ with Burundi and Togo. Nations such as Afghanistan, Pakistan, Benin, Nigeria, and Mauritania, which are known to have problems with illegal logging, also score as poorly.
Countries doing particularly well are either those successfully protecting what little natural forest they have (e.g. Australia, Yemen, Israel, Saudi Arabia), or countries that cut down most of their forests in the past and thus have few forests to manage for growing stock. Countries with very low population density, like Russia and Columbia, also obtained high scores.
There are most likely some countries that received high scores due to misreporting. Expert estimates generally cannot accurately measure illegal logging and fuel wood harvesting, and so it is likely that many countries have received overly optimistic scores.
A total of 62 countries reported increases in forest growing stock over the period 2000-2005. Several of these increases seem large for a 5-year period, but they would be possible if a large measure of “ingrowth” is occurring. Ingrowth is the increase in inventory that results from small trees just passing the threshold for inclusion in the growing stock volume calculation. Ingrowth can be significant if there is abundant young growth.
The countries reporting the highest percentage losses in growing stock are mostly, but not all, smaller nations or nations with small forest areas. Again, losses exceeding 10% in a 5-year period would be extraordinary, but could occur if land use change were fast enough in a country of small forest area.
Forest metrics required for making policy decisions should give a clear sense of long-term trends in forest conditions. Ideal datasets would be made up of consistently collected measurements taken each year in order to capture the direction of change with high resolution. Furthermore, these data should be processed through international institutions that apply a standardized methodology for collecting data. A single forest assessment is simply not sufficient for determining the sustainability of management practices. An improvement in the consistency of national-level monitoring and reporting of forest data is therefore a top priority.
Immediate data priorities for future versions of the EPI include:- Improving growing stock data by using a standardized methodology across all countries, such as high resolution satellite imagery;
- Estimating illegal logging;
- Measuring the value of environmental services: calculating the value of non-timber forest products, including ecosystem services, may stimulate political focus on these often ignored economic values;
- More nuanced evaluation of trends in natural forest vs. plantations and their social, economic, and ecological impacts; and,
- Improving measures of change in forest ecosystems of major environmental concern, such as for example mangroves or forests in major global “conservation hotspots.”
The histograms above represent indicators used to calculate this policy subcategory score. Each dot is a single country’s proximity-to-target value for this indicator. The tinted box represents the inner quartile range of country values, or points lying between the 25th and 75th percentiles. The small triangle marker at the bottom of the chart indicates the median of country scores.
