[EBOOK] Sustainable Agriculture and the Environment in the HUMID TROPICS, Published by NATIONAL ACADEMY PRESS

The increasingly adverse effects of human activities on the earth's land, water, atmospheric, and biotic resources have clearly demonstrated that a new attitude of stewardship and sustainable management is required if our global resources are to be conserved and remain productive. Nowhere is this need more urgent than in the world's humid tropics. Its populations, many subsisting at or below the poverty level, will continue to rely on the resource base to meet their needs. That base must be stabilized while becoming increasingly productive. Thoughtful and prompt actions, especially positive policy changes, are required to break the current pattern of unplanned deforestation in the humid tropics, to reverse environmental degradation caused by improper or mismanaged crop and animal production systems, and to revitalize abandoned lands.

At the request of the U.S. Agency for International Development (USAID), the National Research Council's Board on Agriculture and the Board on Science and Technology for International Development convened the 15-member Committee on Sustainable Agriculture and the Environment in the Humid Tropics. The U.S. Environmental Protection Agency also provided support, emphasizing its interest in the global environmental implications of the problem.

The study responds to the recognized need for sustainable land use systems that (1) maintain the long-term biological and ecological integrity of natural resources, (2) provide economic returns at the farm level, (3) contribute to quality of life of rural populations, and (4) integrate into national economic development strategies. In particular, the committee was asked to identify and analyze key problems of agricultural practices that contribute to environmental degradation and result in declining agricultural production in humid tropic environments.

The committee began its work in March 1990. It sought to understand the overarching environmental, social, and policy contexts of land conversion and deforestation—and the promise of sustainable land uses—by integrating the views of experts in the broad areas of agriculture, ecology, and social sciences. Its work focused on the range of land use systems appropriate to the forest boundary, an area where agriculture and forestry merge in a continuum of production types involving trees, agricultural crops, and animals. The committee addressed intensive, high-input agriculture only as it relates to common environmental problems. The committee undertook supplemental analyses of tropical forest land use policies and the effects of tropical land use on global climate change. We sought a wide range of scientific data, specialized information, and expert views to address our broad charge.

A critical component of the humid tropics equation that was not within the scope of the study is human population. The committee acknowledges population dynamics as a major factor in achieving sustainable land use and development in the humid tropics; the land use systems it describes fit a broad range of population densities. We stress the importance of population issues, particularly in this region of the world, but an analysis of population densities, pressures, and trends was not part of our study, nor does the composition of the committee reflect the demographic expertise necessary to address population issues.

This report, Sustainable Agriculture and the Environment in the Humid Tropics, will contribute to the elusive “solution” to tropical deforestation through its outline of a variety of approaches to tropical land use and conservation. Each land use option would take advantage of the opportunities inherent in physical resource patterns, labor, market availability, and social setting, and each would contribute to the common goal of sustainability in the humid tropics.

The land use options scheme in Chapter 2 and its accompanying table for evaluating land use attributes can be used as a guide in decision making. The presentation makes the information usable by in-country decision makers, from the local level on up, as well as by governmental and nongovernmental agencies. We believe the information in this report will be helpful to researchers, planners, and policymakers in industrialized countries and in developing countries.

Part One Is the committee's deliberative report. It emphasizes the restoration of degraded land, the importance of general economic growth as an alternative to forest exploitation, and the need for comprehensive management of forest and agricultural resources. The underlying premise of the committee's work is that under conditions of economic and social pressure, what is not managed today is at risk of being lost tomorrow.

Within Part One, the Executive Summary discusses the findings of the committee and presents key recommendations. Chapter 1 describes the humid tropics, the consequences of forest conversion and deforestation, environmental factors affecting agriculture, and the fostering of sustainable land use in the humid tropics. Chapter 2 discusses major land use options that local, regional, and national managers might choose in making decisions to achieve food production goals, maintain or increase local income levels, and protect the natural resource base. Chapter 3 discusses technical research needs and presents recommendations on land use options. Chapter 4 presents policy imperatives to promote sustainability. The Appendix to Part One presents a discussion of emissions of greenhouse gases associated with land use change.

To enhance its understanding, the committee commissioned a series of country profiles to gather information on land use and forest conversion in different countries, to evaluate general causes and consequences within specific contexts, to identify sustainable land use alternatives, and to compare policy implications. Seven country profiles are presented in Part Two. Authors review agricultural practices and environmental issues in Brazil, Côte d'Ivoire, Indonesia, Malaysia, Mexico, the Philippines, and Zaire.

The committee's intent in this report is to make a positive statement about the potential benefits of sustainable agriculture in the humid tropics, rather than to condemn the forces that have contributed to the current situation. It is an attempt to promote the restoration and rehabilitation of already deforested lands, to increase their productivity, and to explore the policy changes required to take the next steps toward sustainability. Guidelines for future research and policy, whether for conserving natural ecosystems or for encouraging sustainable agroecosystems, must be designed with a global perspective and within the context of each country's environment, history, and culture.

The committee underscores the fact that sustainable agriculture in any given country will consist of many diverse production systems, each fitting specific environmental, social, and market niches. Some alternatives require higher inputs, labor, or capital—depending on their makeup, resource base, and environment—but each must become more sustainable. Conversely, each system can contribute toward the sustainability of the agricultural system in general by helping to meet the varied and changing needs facing countries in the humid tropics. To maintain a diversity of approaches while making real progress toward common goals is the challenge that confronts all who are concerned with the future of the lands and people of the humid tropics.

RICHARD R. HARWOOD, Chair

Committee on Sustainable

Agriculture and the Environment in the Humid Tropics

[EBOOK] Sustainable Agriculture and the Environment in the HUMID TROPICS, Published by NATIONAL ACADEMY PRESS

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