Contents - Next

This is the old United Nations University website. Visit the new site at

Note from the editors

This book is the third in a series from the United Nations University (UNU) research project, Critical Zones in Global Environmental Change, itself part of the UNU programme on the Human and Policy Dimensions of Global Change. Both endeavours explore the complex linkages between human activities and the environment.

The project views the human causes of and responses to major changes in biogeochemical systems - global environmental change broadly defined - as consequences of cumulative and synergistic actions (or inactions) of individuals, groups, and states, occurring in their local and regional settings. The study examines and compares nine regional cases in which large-scale, human-induced environmental changes portend to threaten the sustainability of an existing system. The aim is to define common lessons about regional trajectories and dynamics of change as well as the types of human actions that breed environmental criticality and endangerment, thereby contributing to global environmental change. The overall results of the comparative analysis are found in Regions at Risk, the initial volume in this series.

The subtitle of Amazonia: Resiliency and Dynamism of the Land and Its People hints at the main message of the book: environmental degradation and socioeconomic obstacles to sustainability notwithstanding, many positive trends bode well for this diverse region. The authors arrive at this message from an in-depth analysis of five main categories of human driving forces - population, new technologies, socio-economic and institutional conditions, beliefs and attitudes, and income and wealth - that interact to alter the physical, social, and cultural environments of Amazonia. Taking a long view both backward and forward, they counter a popular propensity to relegate the whole of Amazonia to history's roll of environmental disasters by documenting the capacity of stressed environments to withstand and even rebound from ecologically damaging trends.

This long-term perspective revealed, well in advance of confirmatory satellite data, that deforestation in Amazonia has been and is likely to be less widespread than conventional wisdom would have it. The authors, while wary of generalizing on trends and opportunities for so vast and heterogeneous a region, recommend development strategies that will increase the productivity of already deforested areas in order to accommodate population growth without endangering the long-term viability of nature-society relationships.


Development pressures are triggering rapid ecological, cultural, and economic changes in Amazonia, one of the world's largest remaining forest frontiers. Some of the environmental effects of development schemes and spontaneous settlement have local and potentially regional and global repercussions. The ecological issues surrounding deforestation include soil erosion, adverse changes in soil structure and fertility, shifts in rainfall patterns, and loss of biodiversity, particularly genetic resources. The driving forces behind land-use changes in Amazonia will be identified, the emerging awareness of economic, cultural, and ecological issues surrounding development will be discussed, and societal responses and management of natural resources will be analysed. A major focus of the study will be identifying resource management strategies for agriculture, particularly in agroforestry systems, silviculture, and pastures. Such an approach should provide information useful for devising development plans for tropical forest ecosystems that are economically viable and environmentally sound.

In the first chapter, "Amazonia under siege," we explore some of the main themes threading through the book, particularly sustainability and one of its major components: resilience. Here we make the point that the ability of human-manipulated systems to rebound after major surprises is critical to the ultimate "success" of any land use. Criticality is defined and sorted into three main categories: environmental criticality, environmental endangerment, and environmental impoverishment. These broad categories represent varying degrees of "seriousness" of human impacts on the environment. These categories provide a convenient template when assessing the overall environmental condition of Amazonia, as well as when we spotlight micro-regions experiencing particularly rapid transformation.

Various real and imagined challenges to the health of the regional and global ecosystems are reviewed in chapter 2, "Environmental threats." Here we attempt to sort out what we consider to be the more ominous challenges to the integrity of Amazonian ecosystems, such as loss of biodiversity, from potential red herrings, such as the role of deforestation in purported global warming. The driving forces behind land transformation and overall societal responses to environmental change are explored in chapter 3, "Forces of change and societal responses."

Five chapters are dedicated to a more detailed examination of underlying causes of environmental change and human responses: "Forest conservation and management" (chap. 4), "Silviculture and plantation crops" (chap. 5), "Agro-forestry and perennial cropping systems" (chap. 6), "Ranching problems and potential on the uplands" (chap. 7), and "Land-use dynamics on the Amazon flood plain" (chap. 8). For each land use, whether forest extraction or ranching, cultural and socio-economic forces for change are highlighted and attempts at more rational use of resources are investigated. Emphasis is placed on what is actually transpiring on the landscape at the individual farm, ranch, and plantation level, rather than hypothetical models or results of experiment station trials.

In the final chapter, "Trends and opportunities," we return to an analysis of overall indicators of criticality, such as wealth and wellbeing and vulnerability. As more of the Amazon is transformed from wilderness to cultural landscapes, the risk of "surprises" is greater, and the need for resilience in human-managed systems increases.

Sizeable portions of Amazonia have already been cleared. If transformed areas were better managed, pressure on the remaining wilderness would be alleviated. A major challenge ahead is to boost the productivity of cleared areas so that population growth and more goods can be coaxed from altered areas without damaging the environment and its people.

A balance is needed between conservation for a variety of environmental services and economic development: success hinges on raising the productivity of all land uses. As productivity levels rise, so will the need to increase and sustain support for research on appropriate resource management strategies. Sustainable development in Amazonia will be possible only by applying modern science as well as tapping indigenous knowledge systems. Although efforts have been made to upgrade the research capacity of local institutions in Amazonia, much remains to be done. Adjustments to policy and fiscal incentives can certainly help improve the outcome of development and conservation projects in the region, but they will be ephemeral unless societies are equipped with the knowledge and skills to respond to challenges.


Many individuals kindly shared their thoughts and ideas on various aspects of Amazonian development and conservation with the authors during the preparation of this book. In particular, we would like to thank the following: Osmar Aguiar, Anthony Anderson, Emelecipío Botelho de Andrade, Ronaldo Baena, Edson Barcelos, Dale Bandy, Luis Coirolo, Peter Cooper, Erick Fernandes, Abe Goldman, Michael Goulding, Alfredo Homma, Socorro Kato, Dennis Mahar, Milton Motta, Olinto Gomes da Rocha Neto, Tatyana Sa, Jan Salick, Pedro Sanchez, Steve Sanderson, Robert Schneider, Rafael Seles, José Ferreira Teixeira Neto, Filemon Torres, Manoel Tourinho, Ann Thrupp, Steve Vosti, and Jonas Veiga. We do not wish to imply that any of the above individuals endorse our findings or views.

Roger Kasperson and William Turner II helped sharpen our thinking on conceptual and methodological issues related to criticality, the driving forces behind environmental change, and societal responses. We also benefited from interactions with other teams involved in case-studies in the series, particularly the opportunity to compare our findings and analytical approaches. An anonymous reviewer for the United Nations University Press made many useful comments on an earlier version of the book manuscript.

Two organizations provided financial support for the project. National Science Foundation grants in 1990 and 1991 launched the research effort and a grant from the United Nations University in 1992 helped complete the project. Funds from these sources permitted NJHS to travel to Brazil in January 1991 to initiate work on the project, provided resources for the co-authors to conduct field trips, and contributed to data analysis and writing.

Many institutions provided invaluable assistance and intellectual input. Several centres of the Brazilian Agricultural Research System (EMBRAPA) kindly provided logistical support and opportunities to interact with scientists working in the region, including CPATU in Pará, CPAF in Acre, CPAA in Amazonas, and CPAF in Rondônia. CPATU, in particular, offered vehicles and the valuable time of staff for numerous field trips in various parts of Pará. Discussions with scientists at the Federal University of Pará and the Museu Goeldi, both in Belem, enriched our thinking about environment and development in Amazonia.

Collaborative work with the above institutions as well as with CIAT (Centro Internacional de Agricultura Tropical) and the Latin AmericaEnvironment (LATEN) section of the World Bank enabled NJHS to make 10 field trips to the Brazilian Amazon between November 1991 and April 1993. During those trips, the senior author was able to gather field data and other information relevant to the book. The co-authors also made numerous field trips to the Brazilian Amazon in connection with other ongoing projects as well as this book.

The views and conclusions expressed in this book are those of the authors and do not necessarily reflect the opinions or positions of any institution.

Contents - Next