Governments, the general public and the international community at large have manifested increasing concern over the clearing and degradation of forests all over the world. This is well reflected by the debate and decisions to issues of forest conservation and development, at the United Nations Conference on Environment and Development (UNCED, Rio, June 1992).
However there cannot be sound decisions and action in the management of forests at any level, whether local or global, without reliable information on their situation and evolution over time. Such information is indispensable whatever the objective of management of forests, be it fuelwood production at local level, timber production for export, conservation of biodiversity or mitigation of climate change. This explains why the assessment and systematic observations of forest resources is a key element in one of the four programme areas of Chapter 11 of UNCED Agenda 21 titled “Combating deforestation”
In pursuance of its mandate, FAO has undertaken periodic assessments of the world's forest resources, of which the first was nearly 50 years ago in 1946 and the last in 1980. The 1990 Global Forest Resources Assessment builds upon the 1980 study. It has three components: (a) the assessment for the tropical countries; (b) the assessment for the industrialized countries which has been carried out and published by FAO and the Economic Commission for Europe of the United Nations; and (c) the assessment for the non-tropical developing countries.
This report provides comprehensive information on the current state of forests in the non-tropical developing countries. New methodology has been developed for more accurate estimation of changes. The core of this methodology is the ability to estimate forest change information from the time series data available with member countries.
Classifications and definitions used in forest inventories differ from country to country, since they are designed to satisfy specific national or local needs. To arrive at a common classification, format and reference date, original data provided by countries had to be reorganized. It must be stressed, however, that the standardized country results published in this international report are intended only to secure a consistent global picture; they do not replace the original country statistics which will remain a unique source of reference.
The 1990 assessment has been a key activity under the FAO Regular Programme, carried out with substantial support from donor countries. Its implementation has benefitted greatly from ready cooperation of all countries which are reported upon here, as well as the technical contributions made by many scientific institutions and individuals. This report also reflects the dedication of Forest Resources Assessment 1990 Project staff.
This assessment is intended to satisfy most of the urgent information needs of policy makers, the scientific community and the general public. However, the exercise has revealed a need to fill major gaps in knowledge and to improve national capacities to carry out their own forest resources assessments. FAO intends to give greater attention to these aspects in future and to make the assessment a continuous and adaptable process.
David A. Harcharik
Assistant Director-General
Forestry Department
The Forest Resources Assessment 1990 of the non-tropical developing countries was supported by the Governments of the Netherlands and France through a multi-donor trust fund. Personnel assistance was given through the Associate Professional Officers scheme of the Government of France. Member countries have contributed by sending source information, and by reviewing the compilations made by FAO. The assessment was conducted by a project team coordinated by Dr. K.D. Singh at FAO, Rome. Mr. Antonio Marzoli, made major contributions in the analyses of data and preparation the draft report. The country database was organized by Messrs. Alberto Del Lungo and Christophe Racaut, Mr. Massimiliano Lorenzini assisted in G.I.S. applications. The Food and Agriculture Organization is greatly indebted to all those who assisted in the implementation of the project by providing information, advice, facilities and funds.
1. Forests are ecological systems with a minimum crown coverage of land surface (here assumed as 10 percent) and generally associated with wild flora, fauna and natural soil conditions; and not subject to agronomic practices. For the present assessments, a tree is defined as a woody perennial with a single main stem (except in coppice crops where multiple stems replace a single stem), a more or less definite crown and a minimum height of more than 5 meters on maturity. Only forest areas more than 100 ha (minimum area) are considered.
It is worthwhile pointing out that the definition of forest used in the present study has a minimum vegetation cover requirement and is quite different from a legal definition of forest (i.e. an area proclaimed to be forest under a Forest Act or Ordinance)
Natural forests are a subset of forests composed of tree species known to be indigenous to the area.
Plantation forests refer to:
Forests established artificially by afforestation on lands which previously did not carry forest within living memory;
Forests established artificially by reforestation of land which carried forest before and involving the replacement of the indigenous species by a new and essentially the same crop as before.
2. Other wooded land includes the following two categories:
Forest fallow refers to all complexes of woody vegetation deriving from the clearing of natural forest for shifting agriculture. It consists of a mosaic of various succession phases and includes patches of uncleared forests and agriculture fields which cannot be realistically segregated and accounted for area-wise, especially from satellite imagery. Forest fallow is an intermediate class between forest and nonforest land uses. Part of the area which is not under cultivation may have appearance of a secondary forest. Even the part currently under cultivation sometimes has appearance of forest, due to presence of tree cover. Accurate separation between forest and forest fallow may not always be possible.
Shrubs refer to vegetation types where the dominant woody elements are shrubs with more than 50 cm and less than 5 meters height on maturity. The height limits for trees and shrubs should be interpreted with flexibility, particularly where the minimum tree and maximum shrub heights, which may vary between 5 and 7 meters approximately.
3. Other Land Use account for the balance of the land area including the following classes:
Arable land
Land under permanent crops
Permanent meadows and pastures
Other land
4. Deforestation is defined in the strict sense of complete clearing of tree formations (closed or open) and their replacement by non-forest land uses (alienation).
5. Forest Degradation takes different forms, particularly in open formations, derived mainly from human activities such as over-grazing, over-exploitation (for fuelwood in particular), repeated fires, or due to attacks by insects, diseases, plant parasites or other natural sources such as cyclones. In most cases forest degradation does not show up so much as a decrease in the area of woody vegetation but rather as a gradual reduction of biomass, changes in species composition and soil degradation. The logging of forests for sawlogs and veneer logs without a proper management plan can contribute to forest degradation if the extraction of mature trees is not accompanied with their regeneration or if the use of heavy machinery causes soil compaction or loss of productive forest area.
