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Executive Summary

In 1999 the world's population reached 6 billion, after doubling in only 40 years. Much of this recent population growth took place in the poorer regions of the world. Fertility and mortality rates began to decline in the Western industrialized regions in the nineteenth century (a process called the demographic transition), but only in the last decades of the twentieth century did some of the developing regions begin to realize significant declines in fertility. Given the population momentum provided by a youthful age structure, populations in many parts of the world will continue to grow for many years to come.

These unprecedented rates of growth, which could have alarming effects on the environment and the life support system of the planet, have renewed the debate about the future prospects for human societies. The high rates of economic and industrial development that accompanied population growth in the twentieth century fed fears about depletion of resources and fouling of the land, air, biota, and water in nearly all parts of the globe. Today's intense debate over the relationship between numbers of people and use of available land has resurrected both Malthus's hypothesis and its critics. The original publication of Thomas Malthus, an eighteenth-century English economist, and those who followed him predicted that the needs of a growing population eventually would exceed the capacity of a finite earth to support it. More optimistic scholars have suggested that limitless human ingenuity will overcome mere physical constraints. Indeed, thus far scientific and technological advances in agriculture have enabled food production to more than keep up with a burgeoning population—on a global level. At the regional and local levels,



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Page 1 Executive Summary In 1999 the world's population reached 6 billion, after doubling in only 40 years. Much of this recent population growth took place in the poorer regions of the world. Fertility and mortality rates began to decline in the Western industrialized regions in the nineteenth century (a process called the demographic transition), but only in the last decades of the twentieth century did some of the developing regions begin to realize significant declines in fertility. Given the population momentum provided by a youthful age structure, populations in many parts of the world will continue to grow for many years to come. These unprecedented rates of growth, which could have alarming effects on the environment and the life support system of the planet, have renewed the debate about the future prospects for human societies. The high rates of economic and industrial development that accompanied population growth in the twentieth century fed fears about depletion of resources and fouling of the land, air, biota, and water in nearly all parts of the globe. Today's intense debate over the relationship between numbers of people and use of available land has resurrected both Malthus's hypothesis and its critics. The original publication of Thomas Malthus, an eighteenth-century English economist, and those who followed him predicted that the needs of a growing population eventually would exceed the capacity of a finite earth to support it. More optimistic scholars have suggested that limitless human ingenuity will overcome mere physical constraints. Indeed, thus far scientific and technological advances in agriculture have enabled food production to more than keep up with a burgeoning population—on a global level. At the regional and local levels,

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Page 2 and at particular times in history, however, hundreds of millions of people have lacked sufficient food or food of adequate quality. Because the conversion of land from its natural state to human use is the most permanent and often irreversible effect that humans can have on the natural landscape, a critical aspect of these debates is the relation of growing population numbers to changes in land use. In general, to meet demands for food farmers must either expand the area of land under cultivation or intensify agricultural practices, which often requires applying large quantities of fertilizer, herbicides, insecticides, and irrigation water and risking their potentially damaging impacts on the environment. Beyond agriculture, other aspects of human consumption, itself a product of increasing population coupled with economic development, may further degrade natural resources and the environment. There is, however, no simple and universal relationship between population growth and land use change. Many other factors, such as geography and climate, come into play, and governments are not without influence on land use conversions. An understanding of the forces at work in regions where land use change has been particularly notable may clarify the issues. In October 1993, representatives of 58 of the world's science academies gathered in New Delhi for a “Science Summit” on World Population. During the meeting, the representatives of the science academies of India, China, and the United States agreed to undertake a unique, multinational collaboration (called here the Tri-Academy Project) that would utilize a case study approach to explore the interactions between population growth and changes in land use in the world's three most populous countries. The study reflects a desire to experiment with inter-academy collaboration as well as intrinsic interest in the topic of the study itself. Bringing together natural and social scientists from the three countries, the project would seek to cast light on the transformations in demographics, land use, and consumption. The John D. and Catherine T. MacArthur Foundation, the U.S. National Institutes of Health, and the U.S. National Research Council agreed to support the undertaking. This study was based on the premise that international comparisons of recorded social transformations may yield insight into principles that could lead to broader generalizations, or at least to recognition of common experience. A perfect design would call for the selection of study sites carefully matched across a spectrum of attributes such as population, land cover, occupations, and geography. Although the panel encouraged such design criteria, each country was responsible for selecting its own sites, under the significant constraint that the studies rely on ongoing work or existing material and not on the collection of new data. One result is that all sites have large populations and high population densities. A base period, roughly the last half-century, was adopted for the comparison of trends, but, where available, much earlier data were used

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Page 3 in the analyses. Even though the case studies described here do include some anecdotal narrative, the panel has emphasized, to the extent possible, quantitative measures of trends. As the findings demonstrate, however, some explanations of changes in land use and population draw on qualitative as well as quantitative observations. Because data on population and land use are collected within different geographical boundaries by different agencies in the three countries, establishing a comparable primary database for the six studies was a difficult undertaking. Early in the study an attempt was made to establish a common database, relying on official, published records in each country, and, generally, the study teams were expected to draw on existing published sources rather than undertake new surveys and measurements. It was recognized from the beginning that there would be problems related to the definition of variables and the compatibility of data used. True comparative analyses are impossible without identically defined, relevant variables expressed in comparable units, but each country has its own land classification scheme and holds to special definitions. Researchers also encountered the problem of verifying data sources. In each case study, team members used both the common database and additional data from more specialized and local studies. Inevitably, there were some inconsistencies between the common database and the case studies, and in the comparative analyses these were resolved in favor of the case studies. STUDY REGIONS The objective of the Tri-Academy Project is to examine the structure of population and land use interactions in six regions. The sites were selected by the respective academies, based on the prior existence of data, availability of research personnel, and the specific interests of each country. They are: in India, Kerala, a subtropical state in southwest India, and Haryana, a state north of New Delhi; in China, the Jitai Basin in Jiangxi Province in southern China and the Pearl River Delta just to the south on the coast; and in the United States, South Florida in the southeastern United States and Chicago and the surrounding region in the American Midwest. Study teams in each region analyzed basic trends in population growth and land use change since World War II and sought to identify drivers of the observed changes. Each case study chapter is authored by members of the local study team. The project team then as a whole compared the trends and drivers across sites and identified general relationships. Kerala has a high life expectancy, a high education rate, and one of the lowest population growth rates in India. The major industry in Kerala is agriculture, and the state's average per capita income is low. The state economy benefits, however, from remittances from expatriate workers.

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Page 4Land use in Kerala is currently influenced by state government policies that encourage cash crop production and by migration from the cities to the highland areas within the state. Haryana and its neighbor state Punjab to the north are the wheat-growing “breadbasket” of India. Haryana's population growth rate is among the highest in India, but it has benefited from the introduction of Green Revolution technologies, and agricultural productivity has been able to keep pace with population. The agricultural land area has remained fairly constant during the state's high-growth period, even though Haryana continues to be an important supplier of food for the country. The inclusion of a chapter on gender issues in development in Kerala and Haryana represents the realization of a fortuitous opportunity. The panel was unable to pursue comparable studies in China and the United States. The Jitai Basin, a center of revolutionary activity in the forties and fifties, was considered a less-developed region of China for most of the twentieth century. Beginning in the 1950s, this agricultural region was heavily affected by radical government policies, including the Great Leap Forward, the “grain production first” system, the Cultural Revolution, and the “household responsibility” system, all of which had detrimental effects on the physical environment. The region is now a focus of Chinese environmental policies. Meanwhile, population has grown slowly, some natural areas (such as wetland, forestland, and grassland) are being restored, and the region remains a source of “floating” workers for the Pearl River Delta to the south. The Pearl River Delta, long a commercial region open to the West, was at one time a center of food production for the South China region. It also was a major source of Chinese immigrants to the West and to Southeast Asia. In 1978 the Chinese government designated several special economic zones in the Delta, areas where foreigners are permitted to invest and local companies are free to export. Since then, the region has experienced rapid urbanization and industrialization and has become a magnet for migrant and “floating” workers from many parts of China. In the United States, South Florida developed rapidly after 1900; throughout the twentieth century decadal growth rates exceeded 100 percent. The primary industry is agriculture, but since World War II tourism and, more recently, financial and trading activities have become key industries. The interaction between population and land use in South Florida is dominated by the influx of migrants from northern U.S. states and immigrants from the Caribbean and Central and South America. Government policies to protect the Everglades and to provide water control structures for agriculture have created a highly inhomogeneous population pattern. Chicago, a small city of 5,000 in 1840, grew at a rate of 10.4 percent per

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Page 5year from 1840 to 1900, when it became known as the world's greatest rail center. Grassland, timber, and livestock provided successive bases for commercial development. The city's population peaked in 1950, and the metropolitan region continues to grow as suburbanization encroaches on agricultural land. People initially migrated to the region to exploit the natural resource base, but with the growth of transportation, communication, and financial institutions, employment in the modern era has shifted from the secondary to the tertiary sector, which provides services to both the regional agricultural sector and the global economy. PROJECT DESIGN AND FINDINGS The research objectives of the Tri-Academy Project are to explore the relations among population growth, consumption patterns, and land use change in the six study regions and to identify issues that will illuminate the principal forces driving the observed changes. The study protocols focused on three broad questions: 1. What is the nature of the significant population and land use transformations in the study regions? 2. To what extent have local population growth and consumption directly influenced the changes in land use? 3. From a comparison of the case studies, what can be learned about the general nature of the forces driving the transformations and about the influence of government policies on population growth and mobility, land use, and economic development? Three general findings emerged from the case studies: 1. The Intertwined Effects of Population, Consumption, and Technology. As noted, the population of each study region is increasing. Migration, as opposed to natural population growth, is the dominant source of these increases in the Pearl River Delta and South Florida, two of the three fastest-growing regions. The effect of local consumption on land use patterns often is less important than that of external consumption. In all regions, the area devoted to subsistence crops has decreased over time and the area sown to market crops has increased. In some regions, local consumption has changed in response—for example, meat, milk, and fish consumption has risen in the Jitai Basin and grain consumption has fallen in Haryana. In the study regions, the impact of technology on the environment was found to be positive or negative, depending on the time and the situation. In Haryana and the Jitai Basin, technological change led to environmental degradation, but more recently in Florida and the Jitai

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Page 6Basin it permitted restoration of natural areas. Green Revolution technology has played a major role in transforming the nature of agricultural land use. 2. Stability and Change on the Land. Contrary to common perceptions, forest areas seem to be stable or even increasing in the study regions of high population density. Grassland and wetland areas, by contrast, are declining and may be more at risk of land use transformation. From 1970 to 1995, total agricultural land in most study regions did not undergo major changes, even though the populations of the regions did grow significantly. Thus, population increases are not uniformly associated with decreases in agricultural land areas. Recovery and restoration of land are possible with appropriate and effective land use policies; however, the ecological and political settings in which they occur may be complex. Finally, land use change has affected the social groups within regions differently. The case studies document differences in effects on upland and lowland groups, on landless people, on women, and on the rural poor. 3. The Importance of Government Policy. Of the various factors mentioned in this report, government policy generally appears to have the greatest single effect on land use change. In the study regions, the effects of government policies are amplified by the fact that no region is a closed system; people, capital, and goods flow across all boundaries. As a result, external forces sometimes have the dominant effect on land use changes. The case studies also reveal that policies often are not motivated by the pressure of population growth and that some policies result in land use changes that provoke increased migration or movement of people. Policies in the study regions that have had a major effect on land use change include: price controls on agricultural inputs and outputs, infrastructure support, taxation, privatization, and reforestation programs. Economic policies have been especially important in the Chinese regions and in Kerala; infrastructure support was important in Haryana and South Florida. CONCLUSION In an increasingly globalized world, places are linked more strongly over greater distances. Understanding the role of government action is critical to understanding how global forces reshape regions and countries. Government policies can offset or mitigate the effects of natural population growth on land use, or they can force or encourage land use changes first, which in turn causes movement of people. At best, policy becomes an important mechanism through which jurisdictions can channel global forces and define opportunities for growth. At worst, global flows of people and capital cause unintended consequences that subvert the intention of government action. Any understanding of the interaction

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Page 7between land use and population in any place will depend on taking into account external and global forces. This observation has important implications for local sustainability initiatives. The true drivers of local environmental change must be identified, and policies intended to foster more sustainable development must be carried out in recognition of the larger context. For example, the success of water restoration projects currently proposed for Haryana depends strongly on a shift in Indian national food supply policies. Similarly, in South Florida transformations in land use are influenced as much by commodity prices, tax incentives, and government infrastructure projects as they are by the pressures of increasing population density. Recognition of the importance of these types of spatial linkages can be a significant step toward more effective environmental management. The case studies in this investigation do not support a view of the world in which land use change and environmental degradation stem purely from the numerical population and its consumption pattern. The most obvious deficiency in most formulas relating population change to development is that the role of social organization—be it economic, political, or cultural—is ignored. In the regions studied here, it is precisely these social actions—from government policy to attitudes toward women—that affect population, consumption, land use, and the environment in profound ways.

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