ISSN 0258-6150


Forest resources assessment 1990

Survey of tropical forest cover and study of change processes

Table of Contents

Technical report of a major global cooperative effort coordinated by the Forest Resources Assessment 1990 Project


Reprinted 1996

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ISBN 92-5-103808-2

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Pan-tropical continuous forest resources survey design

Date: 13/06/81 P/R 185/68Date: 20/07/79 P/R 184/68

Food and Agriculture Organization of the United Nations
Rome © FAO 1996

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Table of Contents




Executive Summary

Chapter I       INTRODUCTION

1.1       Background

1.2       Recent achievements in tropical forest resources assessment

1.3       Objectives of assessment

1.4       Development of the survey design


2.1       Statistical design

2.1.1     Sampling design

2.1.2     Analytical model

2.2       Classification

2.2.1     Definition of forest and forest area changes

2.3       Interdependent interpretation procedure

2.4       Compilation of interpretation results at sampling unit level

2.5       Analysis of change matrices

2.6       Pan-tropical database of change matrices

2.7       Spatial output

2.8       Biomass change analysis


3.1       Selection and procurement of satellite images

3.2       Training and dissemination of methodology

3.2.1      Regional workshops and training sessions

3.3       Interpretation and analysis of sampling units

3.4       Field verification

3.5       Validation of interpretation and compilation results


4.1       Results and analysis at individual sampling unit level

4.2       1980–1990 change processes at global, regional and ecological levels

4.2.1      Global level results (pan-tropical overview)

4.2.2      Regional level results

4.2.3      Ecological level results

4.3       Statistical results by definition of forest (mean estimates and associated error of forest cover and deforestation rates)

4.4       Evaluation of errors

4.4.1      Statistical errors

4.4.2      Change estimate errors

4.4.3      Classification errors


5.1       Relation between the remote sensing survey and FORIS (FAO Forest Resources Information System) databases

5.2       Relation to other global efforts on forest resources monitoring

Chapter VI     WHAT NEXT?

6.1       Subsequent sampling cycles

6.2       Recommended directions for further investigation


7.1       Evaluation of survey design

7.2       Conclusions and recommendations



  Reference SectionTitle
Annex 1 Abstract of papers, technical reports and other documents produced by, or related to, the Forest Resources Assessment 1990 Project 
Annex 2 Project Team
Annex 3 Project Network
Annex 42.1.1Distribution of land area (within Landsat frames) by stratum and sub-region
Annex 52.2Land cover classification
Annex 62.3Evaluation of interpretation procedures
Annex 72.5Analysis and standardization of transition matrices
Annex 82.8Indicative biomass gradient in class-to-class relations
Annex 93.1List of sampling units and satellite images
Annex103.2.1Regional workshops - summary of conclusions and recommendations
Annex114.1Example of results and analysis at individual sampling unit level: SU 4409, north east India
Annex124.2.1Analysis of pan-tropical change matrix
Annex134.2.2Regional level transition matrix and flux diagram - Africa Region
Annex144.2.2Regional level transition matrix and flux diagram - Latin America Region
Annex154.2.2Regional level transition matrix and flux diagram - Asia Region
Annex164.2.3Summary table of the main parameters characterizing the ecological zones
Annex174.2.3Eecological level transition matrix and flux diagram - Wet and Very Moist Zone
Annex184.2.3Eecological level transition matrix and flux diagram - Moist Zone
Annex194.2.3Eecological level transition matrix and flux diagram - Sub-Dry to very Dry Zone
Annex204.2.3Summary table of forest cover changes at eco-regional level


Table number1Title
Table (1.4)1State of forest inventory in the tropics at the end of 1990
Table (2.1.1)1Distribution of Landsat frames by stratum and sub-region
Table (2.1.1)2Allocation of sampling units by region and expected sampling error
Table (2.1.1)3Allocation of sampling units among sub-regions and strata
Table (2.2)1Classification Scheme
Table (2.2.1)1Grouping of land cover classes into land cover categories
Table (2.2.1)2Key to change matrix analysis. Change categories relative to the F3 definition of forest
Table (2.2.1)3Definitions of gross and net deforestation and forest degradation
Table (2.3)1Comparison of various monitoring approaches with reference to the consistency between the historical and recent data
Table (2.7)1Categories of change used in the legend of the raster change maps
Table (2.8)1Indicative biomass density values by land cover class and ecological zone
Table (3.3)1List of the main contributors to the analysis of the 117 Sampling Units of the Pan-tropical Survey
Table (3.4)1Levels of field knowledge that supported the interpretation of satellite images
Table (4.1)1Change matrix of Sampling Unit 4409 in North East India
Table (4.1)2Summary of change assessment results for Sampling Unit 4409
Table (4.1)3Analysis of changes in Sampling Unit 4409
Table (4.2.1)1Pan-tropical area transition matrix for the period 1980–1990
Table (4.2.1)2Summary of forest cover changes in the period 1980–1990
Table (4.2.1)3Pan-tropical transition probability matrix
Table (4.2.1)4Analysis of change
Table (4.2.3)1Ecological stratification (Population parameters)
Table (4.3)1Estimated forest cover, deforestation rates and standard errors at regional and global levels
Table (4.4.1)1Estimated error of area due to dot grid measurement
Table (4.4.3)1Reliability ranking
Table (5)1Main features of four large-scale tropical forest resources surveys

1 Table and Figure identification numbers indicate the report Section of reference, within brackets, and the sequential number within such Section

Figures and Maps

Figure number1Title
Figure (2.1.1)1Sub-regions under assessment
Figure (2.1.1)2Sample design flowchart for a specific sub-region
Figure (2.1.1)3aAfrica region - Sampling frame and selected sampling units
Figure (2.1.1)3bLatin America region - Sampling frame and selected sampling units
Figure (2.1.1)3cAsia region - Sampling frame and selected sampling units
Figure (2.3)1Interdependent interpretation procedure
Figure (2.4)1Compilation System Flowchart
Figure (2.5)1Temporal distribution of recent and historical images of the 117 sampling units
Figure (2.7)1Exemple of raster and vector maps
SU 3517 - Santa Caterina, south Brazil - 1988 acquisition
Figure (4.1)1Woody biomass flux diagram of SU 4409
Figure (4.1)2Raster maps of Sampling Unit 4409
Figure (4.2.1)1Pan-tropical summary of net changes during 1980–1990 by land cover class
Figure (4.2.1)2Pan-tropical woody biomass flux diagram
Figure (4.2.2)1Main categories of forest cover change by geographic region
Figure (4.2.2)2Regional biomass flux diagrams
Figure (4.2.3)1aAfrica region - Map of Ecological zones
Figure (4.2.3)1bLatin America region - Map of Ecological zones
Figure (4.2.3)1cAsia region - Map of Ecological zones
Figure (4.2.3)2Main categories of forest change by ecological zone at regional and pan-tropical levels
Figure (4.2.3)3Flux diagrams of woody biomass by ecological zone (Pan-tropical overview)
Figure (4.3)1Pan-tropical forest cover and relative deforestation rate according to varying definitions of forest
Figure (4.4.3)1Estimated reliability of pan-tropical class transitions
Figure (5.1)1a,bComparison of RS and FORIS estimates of (a) forest cover area, and (b) deforestation area, for the whole pan-tropical sampling frame
Figure (5.1)2Comparison of FORIS and RS forest area estimates at years 1980 and 1990
Figure (5.1)3Comparison of FORIS and RS forest area estimates at year 1990 by geographic region

1 Table and Figure identification numbers indicate the report Section of reference, within brackets, and the sequential number within such Section. Maps are shown with bold characters.