B.A. Stewart – författare

This book brings together current knowledge of terrestrial C sequestration in Central Asia. The themes treated include: biophysical environments, water resources, sustainable agriculture, soil degradation, the effects of irrigation schemes on secondary salinization, soil management and its relationship to carbon dynamics; the relationship between forest management and carbon dynamics, economic analyses of land use practices, important methodological issues arising from the use of GIS, remote sensing, carbon budgeting and scaling, and a review of the knowledge gaps in carbon and climate change. The book is a reference source for soil, water, vegetation, climate, land use and management in the region. The book will be of interest to a wide variety of environmental scientists, economists and those interested in policy issues for the sustainable management of natural resources.

In order to feed their burgeoning populations, developing nations will need to double cereal production by the year 2050. This increase will have to come from existing land, as little potential exists for bringing new land under cultivation -- a daunting prospect when one realizes that increased use and significantly higher concentrations of carbon dioxide have led to a severe depletion of the carbon pool in the world's soils. This is especially telling in developing countries where tropical climates further compromise the soil's ability to recover.In Climate Change and Global Food Security, bestselling editor Rattan Lal heads up a team of the world's top soil scientists and ecologists to document the history of this impending agricultural crisis and explore possible solutions. Throughout this timely text, the authors address six complex themes:1. The impact of projected climate change on soil quality, water resources, temperature regime, and growing season duration on net primary productivity of different biomes2. Soil carbon dynamics under changing climate3. The impact of changes in carbon dioxide and ecological environments on agronomic yields and food production in different regions of the world4. World food demands and supply during the 21st century5. Policy and economic issues related to carbon trading and enhancing agricultural production6. Research and development priorities for enhancing soil carbon pool and food securityThis hard-hitting text is essential reading for anyone involved with soil and crop sciences as well as policy makers and change agents who need to come to the forefront of this issue armed with the latest information and viable solutions.

Since carbon sequestration in soils reduces the amount of carbon available to the atmosphere, the Kyoto Protocols have heightened interest in soil carbon pools and their effect on carbon fluxes. Assessment Methods for Soil Carbon addresses many of the questions related to the measurement, monitoring, and verification of organic and inorganic carbon in soils. The major topics covered are: carbon pools; soil samplingand preparation, analytical techniques for soil carbon; soil erosion and sedimentation; remote sensing, GIS and modeling; procedures for scaling carbon data from point and local measurements to regional and even national scales; and economic and policy issues.In Assessment Methods for Soil Carbon, leading researchers show that we now have the ability to measure, monitor, and verify changes to soil carbon. The book establishes the need for standardized methods that can be used by anyone, and helps us better understand the link between the pedosphere (soils) and the atmosphere. It also shows the importance of developing links between the economics of carbon sequestration and the amounts sequestered, and highlights the need for scientists and policy makers to interact to ensure that policies fit within the scope of present technologies.

Tropical ecosystems - the regions between the tropics of Cancer and Capricorn - play an important role in global processes, economic issues, and political concerns. In their natural state, tropical ecosystems support a large quantity of above- and below-ground biomass, and constitute a major part of the terrestrial carbon pool. Conversion of the natural ecosystem to agriculture and forestry ecosystems disturbs this ecological balance. Global Climate Change and Tropical Ecosystems presents data on carbon pool fluxes from case studies in 12 countries in tropical regions. The chapters cover:Characteristics of tropical ecosystems Soil and biotic carbon pools Impacts of land use and soil management Slash-and-burn practices Crop residue and fertility managementThis volume adds to the understanding of pedospheric processes in tropical ecosystems and how to better use soils as a sink for carbon dioxide and other greenhouse gases. With Global Climate Change and Tropical Ecosystems you will understand the link between soil productivity, environmental quality and the global carbon cycle, not only in these ecologically sensitive regions but worldwide.

This unique book examines the beneficial aspects of animal waste as a soil resource - not simply as an agricultural by-product with minimal practical use. Topics include o types of livestock waste - swine, poultry, dairy o methods and management of waste utilization o storage, handling, processing and application of animal waste o supplying crop nutrients o economics of waste utilization o new modeling and management techniques o nonpoint source pollution, water quality, leaching, and air quality.

Soil degradation has serious global impacts on agronomic, economic, and sociopolitical conditions, however, statistics regarding the degree of these impacts has been largely unreliable. This book aims to standardize the methodology for obtaining reliable and objective data on soil degradation. It will also identify and develop criteria for assessing the severity of soil degradation, providing a realistic scenario of the problem.

Soils comprise the largest pool of terrestrial carbon and therefore are an important component of carbon storage in the biosphere-atmosphere system. Structure and Organic Matter Storage in Agricultural Soils explores the mechanisms and processes involved in the storage and sequestration of carbon in soils. Focusing on agricultural soils - from tropical to semi-arid types - this new book provides an in-depth look at structure, aggregation, and organic matter retention in world soils.The first two sections of the book introduce readers to the basic issues and scientific concepts, including soil structure, underlying mechanisms and processes, and the importance of agroecosystems as carbon regulators. The third section provides detailed discussions of soil aggregation and organic matter storage under various climates, soil types, and soil management practices. The fourth section addresses current strategies for enhancing organic matter storage in soil, modelling techniques, and measurement methods.Throughout the book, the importance of the soil structure-organic matter storage relationship is emphasized. Anyone involved in soil science, agriculture, agronomy, plant science, or greenhouse gas and global change studies should understand this relationship. Structure and Organic Matter Storage in Agricultural Soils provides an ideal source of information not only on the soil structure-storage relationship itself, but also on key research efforts and direct applications related to the storage of organic matter in agricultural soils.

Agrochemicals and agricultural practices have a tremendous impact on environmental quality, particularly their role in water quality degradation. Soil Processes and Water Quality examines principles and practices that minimize the risks of water pollution while enhancing agricultural intensification and productivity. It focuses on how agricultural practices-such as tillage methods, use of fertilizers and manures, cropping systems, and the use of agrochemicals and pest control measures-impact soil processes and affect water quality. Extensive coverage of such topics as water contamination by runoff, leaching, macropore flow, and sediments is also included.Rapid increases in the use of agrochemicals make Soil Processes and Water Quality an indispensable reference for soil scientists, water quality professionals, researchers, environmental chemists, agrochemicals professionals, government agency employees, academic instructors, agronomists, and students.

Interacting Processes in Soil Science focuses on coupled processes in soil. Topics covered in this important volume include the effects of inorganic salts upon water flow, modeling of sorption, transport and transformation of organic solutes, and the effects of microorganisms on silicate clay minerals. The book presents studies and approaches that can be extended and complemented by innovative work in the future.Interacting Processes in Soil Science will be an essential reference for all researchers and students in soil science, soil and water engineering, civil and environmental engineering, earth sciences, and hydrology.

Developments in soil classification have accompanied parallel progress in our understanding of the soil system. However the theories behind the classifications and the purposes for which they were created have changed over time. The editors hope that this comprehensive synthesis will help to rally soil scientists around the world to develop an acceptable classification system for soils. It is only when the global soil science community agrees to such a system that we can truly say that we have science.Soil Classification: A Global Desk Reference is the first book to illustrate the current state of national and international soil classification systems. In this groundbreaking reference, distinguished soil scientists, many of whom were involved in the design of their respective national or international systems, evaluate developments in soil classification during the last century. They review the concepts, practices, and goals that led to the creation of individual classification systems and recommend modifications to classification systems to meet new demands. The documentation in this book serves as a foundation for the revision of existing soil taxonomies and the creation of new ones.

The most complete, nonpartisan source of information on this hot agronomic topic available today, this book brings together a diverse group of papers and data to resolve the debate between sedimentologists and soil scientists and agronomists over whether the effects of soil erosion on carbon and atmospheric CO2 is beneficial or destructive. Divided into four sections, it offers data on how soil erosion affects soil, water, and air quality. Topics include mineralization rate, inundation, sediment deposition, and global warming potential, as well as carbon dioxide, methane, and nitrous oxide emissions, and the implications of soil erosion on the global carbon cycle and carbon budget.

This book brings together current knowledge of terrestrial C sequestration in Central Asia. The themes treated include: biophysical environments, water resources, sustainable agriculture, soil degradation, the effects of irrigation schemes on secondary salinization, soil management and its relationship to carbon dynamics; the relationship between forest management and carbon dynamics, economic analyses of land use practices, important methodological issues arising from the use of GIS, remote sensing, carbon budgeting and scaling, and a review of the knowledge gaps in carbon and climate change. The book is a reference source for soil, water, vegetation, climate, land use and management in the region. The book will be of interest to a wide variety of environmental scientists, economists and those interested in policy issues for the sustainable management of natural resources.

In order to feed their burgeoning populations, developing nations will need to double cereal production by the year 2050. This increase will have to come from existing land, as little potential exists for bringing new land under cultivation -- a daunting prospect when one realizes that increased use and significantly higher concentrations of carbon dioxide have led to a severe depletion of the carbon pool in the world's soils. This is especially telling in developing countries where tropical climates further compromise the soil's ability to recover.In Climate Change and Global Food Security, bestselling editor Rattan Lal heads up a team of the world's top soil scientists and ecologists to document the history of this impending agricultural crisis and explore possible solutions. Throughout this timely text, the authors address six complex themes:1. The impact of projected climate change on soil quality, water resources, temperature regime, and growing season duration on net primary productivity of different biomes2. Soil carbon dynamics under changing climate3. The impact of changes in carbon dioxide and ecological environments on agronomic yields and food production in different regions of the world4. World food demands and supply during the 21st century5. Policy and economic issues related to carbon trading and enhancing agricultural production6. Research and development priorities for enhancing soil carbon pool and food securityThis hard-hitting text is essential reading for anyone involved with soil and crop sciences as well as policy makers and change agents who need to come to the forefront of this issue armed with the latest information and viable solutions.

Developments in soil classification have accompanied parallel progress in our understanding of the soil system. However the theories behind the classifications and the purposes for which they were created have changed over time. The editors hope that this comprehensive synthesis will help to rally soil scientists around the world to develop an acceptable classification system for soils. It is only when the global soil science community agrees to such a system that we can truly say that we have science.Soil Classification: A Global Desk Reference is the first book to illustrate the current state of national and international soil classification systems. In this groundbreaking reference, distinguished soil scientists, many of whom were involved in the design of their respective national or international systems, evaluate developments in soil classification during the last century. They review the concepts, practices, and goals that led to the creation of individual classification systems and recommend modifications to classification systems to meet new demands. The documentation in this book serves as a foundation for the revision of existing soil taxonomies and the creation of new ones.

World soils contain about 1500 gigatons of organic carbon. This large carbon reserve can increase atmospheric concentrations of CO2 by soil misuse or mismanagement, or it can reverse the 'greenhouse' effect by judicious land use and proper soil management.Soil Processes and the Carbon Cycle describes soil processes and their effects on the global carbon cycle while relating soil properties to soil quality and potential and actual carbon reserves in the soil. In addition, this book deals with modeling the carbon cycle in soil, and with methods of soil carbon determinations.

Soil degradation has serious global impacts on agronomic, economic, and sociopolitical conditions, however, statistics regarding the degree of these impacts has been largely unreliable. This book aims to standardize the methodology for obtaining reliable and objective data on soil degradation. It will also identify and develop criteria for assessing the severity of soil degradation, providing a realistic scenario of the problem.

Interacting Processes in Soil Science focuses on coupled processes in soil. Topics covered in this important volume include the effects of inorganic salts upon water flow, modeling of sorption, transport and transformation of organic solutes, and the effects of microorganisms on silicate clay minerals. The book presents studies and approaches that can be extended and complemented by innovative work in the future.Interacting Processes in Soil Science will be an essential reference for all researchers and students in soil science, soil and water engineering, civil and environmental engineering, earth sciences, and hydrology.

Agrochemicals and agricultural practices have a tremendous impact on environmental quality, particularly their role in water quality degradation. Soil Processes and Water Quality examines principles and practices that minimize the risks of water pollution while enhancing agricultural intensification and productivity. It focuses on how agricultural practices-such as tillage methods, use of fertilizers and manures, cropping systems, and the use of agrochemicals and pest control measures-impact soil processes and affect water quality. Extensive coverage of such topics as water contamination by runoff, leaching, macropore flow, and sediments is also included.Rapid increases in the use of agrochemicals make Soil Processes and Water Quality an indispensable reference for soil scientists, water quality professionals, researchers, environmental chemists, agrochemicals professionals, government agency employees, academic instructors, agronomists, and students.

Nitrogen (N) is potentially one of the most complex elements on the Earth. It is necessary for all biological activity, but creates negative impacts on water and air quality. There is a balancing act between deficiency and surplus and the forms of N available further complicate our understanding of the dynamics. Biological fixation provides some plants with N supply while others are totally dependent upon N being available in the soil profile for the roots to extract. Nevertheless, the demand for N will increase because the human population with its increasing growth requires more protein and thus more N. Understanding the global N cycle is imperative to meeting current and future nitrogen demands while decreasing environmental impacts. This book discusses availability, production, and recycling of N in air, water, plants, and soils. It features information on N impacts to soil and water quality, management of N in agroecosystems, and techniques to maximize the use efficiency while minimizing the risks of leakage of reactive N into the environment. This volume in the Advances in Soil Science series is specifically devoted to availability, production, and recycling of N with impact on climate change and water quality, and management of N in agroecosystems in the context of maximizing the use efficiency and minimizing the risks of leakage of reactive N (NO-3, N¬2O) into the environment.

Phosphorus is an essential plant nutrient, but global population growth has dramatically reduced the availability of phosphorus fertilizer resources. Despite this scarcity, there remain numerous problems associated with the excessive and inappropriate use of phosphorus leading to non-point source pollution and eutrophication of natural waters. Identifying appropriate systems for managing soil phosphorus and reducing the risks of eutrophication are needed to minimize the environmental risks. This book focuses on the availability and recycling of phosphorus; regulatory and policy issues of sustainable phosphorus use; and water quality management in agroecosystems pertaining to phosphorus. Sections are dedicated to global phosphorus reserves; cycling and pathways of phosphorus; phosphorus in agriculture; human dimensions and policy intervention; and research and development priorities.Phosphorus is a finite but crucial resource and is an essential element to all life. Sub-optimal availability and nutrient imbalance in the root zone can adversely impact plant growth, and the quality of food and feed grown on these soils. However, the proven reserves of phosphorus can hardly be adequate for a few centuries only. Yet, its misuse and mismanagement has caused severe problems of eutrophication of water and pollution of the environment. Thus, judicious management of soil phosphorus is essential. This volume is specifically devoted to availability and recycling of phosphorus, regulatory/policy issues of sustainable use of phosphorus, and management in agroecosystems in the context of maximizing the use efficiency and minimizing the environmental risks of water quality.

Faced with challenges of resource scarcity and environmental degradation, it is important to adopt innovative farming systems that maximize resource efficiency while protecting the environment. Soil-Specific Farming: Precision Agriculture focuses on principles and applications of soil-specific farming, providing information on rapidly evolving agricultural technologies. It addresses assessments of soil variability and application of modern innovations to enhance use efficiency of fertilizers, irrigation, tillage, and pesticides through targeted management of soils and crops. This book provides the technological basis of adopting and promoting precision agriculture (PA) for addressing the issues of resource scarcity, environmental pollution, and climate change. It focuses specifically on PA technologies and discusses historical evolution, soil variability at different scales, soil fertility and nutrient management, water quality, land leveling techniques, and special ecosystems involving small landholders and coastal regions. Highlighting the scale-related issues and concerns of small landholders, the text details the efficient use of resources on the basis of soil/field variability and site-specific conditions. It examines how PA technology can increase productivity, enhance profitability, and minimize environmental degradation. Woven throughout is the theme of sustainable use of resources.

From its humble beginning in the late 19th century―when Henry Ford’s first car was designed to run on ethanol―biofuel production has been on the rise with more than 26 billion liters produced in the U.S. in 2007. Ethanol made from biomass (rather than grains) holds great promise, including numerous economic and environmental benefits. However, the adverse interactions of energy, climate, food, and soil quality cannot be ignored. In eight concise chapters, Soil Quality and Biofuel Production presents a state-of-the-knowledge review of soil properties and processes negatively impacted by crop residue removal. It outlines the ecological consequences of biofuels and evaluates land use in the production of raw material for biofuel. The book then spotlights pressing issues related to corn and cellulosic ethanol and also soil erosion. It offers advice for achieving economic balance in the competition for arable land between food and biofuel along with residue harvest management techniques. A thought-provoking discussion of the opportunities and challenges that biofuel presents rounds out the book’s coverage.The logistics of producing biomass in a sustainable manner remain a major challenge and will continue to be so for the foreseeable future. Serious questions linger concerning viable sources of biofuel feedstock, competition for resources needed to produce biomass, and energy output/input ratios. Soil Quality and Biofuel Production provides environmental scientists and agricultural engineers with the knowledge they need to address them.

Just five years ago, it was generally believed that the number of food insecure people in the world was on continuous decline. Unfortunately, widespread soil degradation along with resistance to recommended agronomic practices, and little attempt to restore degraded soils have conspired with significant droughts (in regions that could least tolerate them) to swell the ranks of the food insecure to over a billion people. The U.N. Millennium Development Goals’ intent to halve hunger by 2015 will not be realized. Food Security and Soil Quality brings together leading experts from across the world to provide a concise and factually supported exploration of the problem at hand and the critical steps needed to reverse it. Edited by Rattan Lal, and B.A. Stewart, two of the world’s most respected soil scientists, this important work — Assesses farming systems and food security in Sub-Saharan Africa, with special emphasis on land degradationExamines concerns with and approaches to soil quality management in Brazil and ChinaDetails achievable methods for improving soil quality for sustainable production Provides an insightful comparison of temporal changes in agricultural systems productivity in Punjab, India and Ohio Discusses the human dimension of the crisis including the influence of culture and spiritual beliefsDr. Lal himself writes that despite the existence of scientific data on sustainable management of soil and water resources, problems of soil and environmental degradation have persisted and have been aggravated. And that these problems are rooted in land misuse and soil mismanagement. This book does provide policymakers and others with an understanding of the depth, complexity, and immediacy of this crisis, but more than a call to action, it also offers soil scientists working in this area with an understanding of what is being done and what needs to be done. Most importantly, this book helps us understand that the situation is not beyond remediation were we to act with great resolve and a sense of urgency. A tree's leaves may be ever so good, So may its bark, so may its wood; But unless you put the right thing to its root,It never will show much flower or fruit.— from Leaves Compared With Flowers, by Robert Frost

The application of fractals and fractal geometry in soil science has become increasingly important over the last few years. This self-contained and timely book was designed to provide detailed and comprehensive information on the current status of the application of fractal geometry in soil science, and on prospects for its future use. With a detailed and specific introductory chapter, particular attention is paid to comparing and contrasting "fractal" and "fragmentation" concepts. Some uses of fractals, such as to quantify the retention and transport properties of soils, to describe the intricate geometry of pore surfaces and macropore networks, or to elucidate the rooting patterns of various plants, are discussed. Applications of fractals in soil science are both relatively recent and in constant evolution. This book reflects accurately existing trends, by allowing sharp differences among the viewpoints expressed in contributed chapters to be presented to the reader in one self-contained volume.

The application of fractals and fractal geometry in soil science has become increasingly important over the last few years. This self-contained and timely book was designed to provide detailed and comprehensive information on the current status of the application of fractal geometry in soil science, and on prospects for its future use. With a detailed and specific introductory chapter, particular attention is paid to comparing and contrasting "fractal" and "fragmentation" concepts. Some uses of fractals, such as to quantify the retention and transport properties of soils, to describe the intricate geometry of pore surfaces and macropore networks, or to elucidate the rooting patterns of various plants, are discussed. Applications of fractals in soil science are both relatively recent and in constant evolution. This book reflects accurately existing trends, by allowing sharp differences among the viewpoints expressed in contributed chapters to be presented to the reader in one self-contained volume.

Nitrogen (N) is potentially one of the most complex elements on the Earth. It is necessary for all biological activity, but creates negative impacts on water and air quality. There is a balancing act between deficiency and surplus and the forms of N available further complicate our understanding of the dynamics. Biological fixation provides some plants with N supply while others are totally dependent upon N being available in the soil profile for the roots to extract. Nevertheless, the demand for N will increase because the human population with its increasing growth requires more protein and thus more N. Understanding the global N cycle is imperative to meeting current and future nitrogen demands while decreasing environmental impacts. This book discusses availability, production, and recycling of N in air, water, plants, and soils. It features information on N impacts to soil and water quality, management of N in agroecosystems, and techniques to maximize the use efficiency while minimizing the risks of leakage of reactive N into the environment. This volume in the Advances in Soil Science series is specifically devoted to availability, production, and recycling of N with impact on climate change and water quality, and management of N in agroecosystems in the context of maximizing the use efficiency and minimizing the risks of leakage of reactive N (NO-3, N¬2O) into the environment.

Just five years ago, it was generally believed that the number of food insecure people in the world was on continuous decline. Unfortunately, widespread soil degradation along with resistance to recommended agronomic practices, and little attempt to restore degraded soils have conspired with significant droughts (in regions that could least tolerate them) to swell the ranks of the food insecure to over a billion people. The U.N. Millennium Development Goals’ intent to halve hunger by 2015 will not be realized. Food Security and Soil Quality brings together leading experts from across the world to provide a concise and factually supported exploration of the problem at hand and the critical steps needed to reverse it. Edited by Rattan Lal, and B.A. Stewart, two of the world’s most respected soil scientists, this important work — Assesses farming systems and food security in Sub-Saharan Africa, with special emphasis on land degradationExamines concerns with and approaches to soil quality management in Brazil and ChinaDetails achievable methods for improving soil quality for sustainable production Provides an insightful comparison of temporal changes in agricultural systems productivity in Punjab, India and Ohio Discusses the human dimension of the crisis including the influence of culture and spiritual beliefsDr. Lal himself writes that despite the existence of scientific data on sustainable management of soil and water resources, problems of soil and environmental degradation have persisted and have been aggravated. And that these problems are rooted in land misuse and soil mismanagement. This book does provide policymakers and others with an understanding of the depth, complexity, and immediacy of this crisis, but more than a call to action, it also offers soil scientists working in this area with an understanding of what is being done and what needs to be done. Most importantly, this book helps us understand that the situation is not beyond remediation were we to act with great resolve and a sense of urgency. A tree's leaves may be ever so good, So may its bark, so may its wood; But unless you put the right thing to its root,It never will show much flower or fruit.— from Leaves Compared With Flowers, by Robert Frost

From its humble beginning in the late 19th century―when Henry Ford’s first car was designed to run on ethanol―biofuel production has been on the rise with more than 26 billion liters produced in the U.S. in 2007. Ethanol made from biomass (rather than grains) holds great promise, including numerous economic and environmental benefits. However, the adverse interactions of energy, climate, food, and soil quality cannot be ignored. In eight concise chapters, Soil Quality and Biofuel Production presents a state-of-the-knowledge review of soil properties and processes negatively impacted by crop residue removal. It outlines the ecological consequences of biofuels and evaluates land use in the production of raw material for biofuel. The book then spotlights pressing issues related to corn and cellulosic ethanol and also soil erosion. It offers advice for achieving economic balance in the competition for arable land between food and biofuel along with residue harvest management techniques. A thought-provoking discussion of the opportunities and challenges that biofuel presents rounds out the book’s coverage.The logistics of producing biomass in a sustainable manner remain a major challenge and will continue to be so for the foreseeable future. Serious questions linger concerning viable sources of biofuel feedstock, competition for resources needed to produce biomass, and energy output/input ratios. Soil Quality and Biofuel Production provides environmental scientists and agricultural engineers with the knowledge they need to address them.

Soil—The Basis of All Terrestrial LifeAncient civilizations and cultures—Mayan, Aztec, Mesopotamian, Indus, and Yangtze—were built on good soils, surviving only as long as soils had the capacity to support them. In the twenty-first century, productive soil is still the engine of economic development and essential to human well-being. The quality of our soil resources, however, is threatened by human-induced and natural perturbations. World Soil Resources and Food Security takes an in-depth look at the availability and status of soil resources in the context of the growing demands of an increasing world population and rising expectations of living standards. This timely reference presents current information on the soil resources available for food production. Presenting innovative strategies for soil and water management, it discusses how to maintain or improve the world’s soil resources in order to increase food production. With the majority of the world’s 1.02 billion food-insecure people concentrated in South Asia and sub-Saharan Africa, several chapters focus on soil resources in these regions.Contributions from renowned scientists deal with topics including: Global food situations World soil resources Soil resources of humid Asia and their acidification Soil resources of South Asia Properties and management of Vertisols Use of radioisotopic techniques in soil management The potential of rain-fed agriculture in the semiarid tropics The status of land degradation Nutrient balance in sub-Saharan Africa The book concludes by outlining the need for further research to generate credible data on soil resources and degradation. This volume is a useful resource for those interested in the state of the soils of the world in relation to food security and environmental quality.