This chapter examines the changes that have occurred in farming over the past 10,000 years and which continue today. Agriculture and food play an important role in the economic systems of all countries and regions. Indeed, crop and animal domestication — integral to the practices of farming — were essential for the development of human civilizations. Agricultural systems in different regions of the world differ in their productivity, and in the modern world, scientific and technological discoveries are responsible for many of those differences. Whereas modern science-driven agriculture is highly productive, especially in developed countries, a billion smallholder farmers in developing countries are confined to small farms where productivity is low and where they produce just enough food to supply themselves with the bare essentials of life.
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Chapter
A Changing Global Food System
One Hundred Centuries of Agriculture
H. Maelor Davies and Paul Gepts
Chapter
Abiotic Stress
This chapter provides an integrated view of how plants adapt and respond to abiotic stresses in the environment, beginning with a distinction between adaptation and acclimation in relation to abiotic stress. It describes the various abiotic factors in the environment that can negatively affect plant growth and development. It also analyzes plant stress-sensing mechanisms and processes that transform sensory signals into physiological responses. The chapter talks about specific metabolic, physiological, and anatomical changes that result from signaling pathways and that enable plants to adapt or acclimate to abiotic stress. It illustrates how efforts to enhance the abiotic stress tolerance of plants can improve agricultural yield and how the different physiological processes affected in plants during abiotic stress can be used for plant monitoring and treatment in the field using precision agriculture practices.
Chapter
Water and Plant Cells
This chapter considers how water moves into and out of plant cells, emphasizing the molecular properties of water and the physical forces that influence water movement at the cellular level. It points out that water is the most abundant and yet often the most limiting of all the resources that plants need to grow and function. It also highlights the practice of crop irrigation that reflects the fact that water is a key resource limiting agricultural productivity and the availability of water that limits the productivity of natural ecosystems, which leads to marked differences in vegetation type along precipitation gradients. The chapter considers how the structure of water gives rise to some of its unique physical properties. It examines the physical basis for water movement, the concept of water potential, and the application of this concept to cell water relations.
Chapter
The Evolutionary Story of Homo sapiens
This chapter explores the evolutionary story of Homo sapiens. It explains how humans
descended from the last universal common ancestor of all living organisms on Earth,
referencing the fundamental features of inheritance based on nucleic acids, the genetic
code, and proteins composed of L-amino acids. Natural selection and evolution are ongoing in
human populations, even in industrialized societies. The chapter then discusses how
agriculture profoundly changed the environment in which humans were living, which also
resulted in the evolution of culture that enabled humans to occupy more different
environments, over a broader geographic area. It elaborates on the key differences between
cultural evolution and genetic evolution.
Chapter
Microbial Biotechnology and Agriculture
This chapter examines the important role microbes play in the future of sustainable agriculture. It looks into microbes as biological control agents and the use of bacteria as genetic tools and microbial inoculants. The challenge of microbial biotechnology and agriculture involves combating climate change, plant pathogens, and sustainable living. The chapter then cites the limitation of biological control agents as a result of their ability to control a narrow range of pests, slow action, and short field life. It also presents microbes that are used as tools in genetic modification, referencing the Agrobacterium-mediated system for the genetic modification of plants.
Chapter
Food Security
Meredith T. Niles and Molly E. Brown
This chapter discusses the concepts of food security and its connection to sustainability. It looks at where food is produced, by whom it is produced, and how humans then move and use this food around the planet. The chapter first defines the expanding concept of food security, which has begun with narrower concerns of providing enough food and, more recently, encompassing social and cultural issues. The chapter also introduces the four pillars of food security: availability, access, utilization, and stability. Then the discussion explores urban agriculture as well as the use of satellite information and Internet-connected devices to improve farm management.
Chapter
Soils
What are the impacts of agriculture on soils?
Paul F. Hudson, Peter Houben, and Thijs Bosker
This chapter focuses on the impacts of agriculture on soil, which is a vital natural resource for food production and provides a range of ecosystem services. About 95% of the world's food production comes from the soil while the remaining 5% comes from glass greenhouses and fisheries. The chapter describes the basic components of soil and the soil ecosystem services: provisioning, supporting, regulating, and cultural services. The discussion emphasizes that about a third of global soil resources already have been degraded by human activities, mostly due to modern agricultural practices. The chapter also tackles the key causes of soil degradation: water and wind erosion, pollution, and salinization. Furthermore, the chapter reviews how to examine a soil horizon and explores hydroponic agriculture – the growing of crops outside the soil.
Chapter
Innovations in Agriculture
How Farm Technologies Are Developed and How They Reach Farmers
H. Maelor Davies
This chapter explores how farm technologies are developed and how they reach farmers. Farmers obtain seeds in one or more of four different ways. They may obtain seed freely through sharing with other farmers; purchase from seed companies with no restrictions on their future propagation; purchase seed of varieties suitable for only one crop-production cycle; and/or purchase with formal agreement that limits use to a single crop-production cycle. The ability to patent plant varieties combined with the development of advanced plant genetics led to considerable consolidation of the seed-supply industry. The chapter then looks at how domination of the seed-supply for the major crops by just a few large companies has led to concerns about limited genetic diversity among the major crops, and debate about who actually owns plant varieties. It considers how agricultural technologies and practices are subject to oversight and regulation.
Chapter
The Human Population and Its Food Supply in the 21st Century
Maarten J. Chrispeels and Hanya E. Chrispeels
This chapter discusses the past, present, and future of the human population and its relationship to food production. In the past, the uncertainties of food production too often have led to food insecurity, and the future holds further uncertainties posed by climate change. Rapid urbanization in developing countries is changing where vegetables are grown and how they are made available to consumers. The depopulation of the land means that farming will have to become more efficient and less labour intensive. There is agreement among agricultural scientists that the way forward is to increase the productivity of farmland everywhere and to do this sustainably, reducing the impact of agriculture on the environment. The chapter then looks at how government policies play pivotal roles in global food production, as well as the importance of agricultural research and biotechnology.
Book
Maarten J. Chrispeels and Paul Gepts
Plants, Genes, and Agriculture looks at the human population and the food supply now and how the global food system has changed over time. It looks at the role of plants in the human diet. It considers the importance of genes, genomics, and molecular biology. It asks how we can convert solar energy into crop-production and considers innovations in agriculture. The text also looks at soil ecosystems, plant nutrition, biotic challenges from weeds, plant diseases, biotic changes, and abiotic stress. The text then considers food safety, and asks specifically if foods made from GE crops are safe to eat. It ends looking at how technology has impacted plants and agriculture over the last few years.
Chapter
Future Challenges and Perspectives In Cell Signalling
This chapter looks at selected methods for measuring the levels of cell signalling components and discusses the notion of compartmentalization. It describes how signalling is a balance and states that threshold levels allow signalling to be propagated. It also explains how cell signalling systems can be manipulated to improve human health and agriculture outputs. The chapter traces the history of medicine, which has produced numerous drugs that have their targets in cell signalling mechanisms. It highlights that a significant amount of effort is now focused on the manipulation of G protein-coupled receptors (GPCRs), which appears promising for drug development. Treatments that target cell signalling in plants will likely have a transformative impact on agriculture, as they may allow for crops to be improved where soils are contaminated or where climate change has an effect.
Chapter
Artificial Selection
This chapter highlights artificial selection—the deliberate choice of certain individuals to propagate a line. This has been the mechanism for producing all the modern varieties of domestic animals and crop plants. Indeed, the application of evolutionary principles to practical problems has been essential to the great expansion of agricultural productivity on which modern civilization is based. At the same time, artificial selection is itself a powerful method for investigating these principles. The chapter then looks at how artificial selection produces rapid and predictable change in the short term and considers domestication as applied artificial selection. It also examines how artificial selection can produce extensive adaptive radiations.
Chapter
Climate Change and Agriculture
This chapter discusses how climate change affects agriculture, which plays a major role in providing food for a growing global population. Climate has an impact on agriculture through the effects of such variables as solar radiation, temperature, and rainfall. Moreover, extreme events such as heatwaves, frosts, wind storms, floods, and droughts can have catastrophic effects on agriculture. The chapter also looks into the process of achieving optimal climatic conditions for crops and livestock. It provides an overview of the impacts of climate change in line with the development of climate change adaptation strategies dedicated to agriculture, particularly the wine sector.
Chapter
Biodiversity, Ecosystem Services, and Climate Change
This chapter covers the interplay between biodiversity, Ecosystem Services (ES), and climate change. It discusses how healthy biodiversity will help people tackle threats from climate change, referring to the significance of traditional nature reserves and protected areas. Moreover, ES and Nature Based Solutions are being used increasingly to highlight ways in which nature helps to make human life both possible and worth living. The chapter explains the provisioning of ecosystem services, particularly agriculture, forestry, and fisheries. It shows that attempts to protect the essential biodiversity needed to maintain and strengthen future ES in the face of climate change will depend on wide and prolonged community involvement.
Book
Kay Yeoman, Beatrix Fahnert, David Lea-Smith, and Tom Clarke
Microbial Biotechnology introduce topics at the forefront of this field that are being applied to probe biological problems, or to address the most pressing issues facing society. These topics include those that form the cornerstone of contemporary research. Chapters cover the essentials of microbial biotechnology, its applications in agriculture, diagnostics, and urban and artistic conservation, as well as the potential threats genetic modification may pose to public health, the environment and intellectual property.
Chapter
Biodiversity
What are the impacts of food production on biodiversity?
Thijs Bosker, Ellen Cieraad, and Krijn Trimbos
This chapter looks at biodiversity, the variety of life on Earth. It underscores that biodiversity is currently being lost at an alarming rate, pointing out that extinction rates are estimated to be 100- to 1000-fold higher than natural extinction levels. The chapter also discusses the five key threats to global biodiversity: habitat fragmentation, the introduction of invasive species, pollution, climate change, and the overexploitation of ecosystems. Then it examines how agriculture impacts other animals and plants. It describes the strategies of land sparing and land sharing, as well as the concept of rewilding. The chapter concludes with a discussion on biodiversity conservation efforts in agriculture such as agri-environmental schemes and nature-inclusive agriculture.
Chapter
Food Toxicity and Safety
Peter Williams and Paul Brent
This chapter evaluates food toxicity and safety. Very few of the foods that we commonly eat have been subject to any toxicological testing and yet they are generally accepted as being safe to eat. However, all chemicals, including those naturally found in foods, are toxic at some dose. ‘Risk’ is the probability that the substance will produce injury under defined conditions of exposure. The concept of risk takes into account the dose and length of exposure, as well as the toxicity of a particular chemical, and is a better guide to the safety of a food. The chapter then looks at hazardous substances in food; microbial contamination; environmental contamination; natural toxins; agricultural residues; intentional food additives; and novel foods. It also identifies the regulatory agencies that manage food safety legislation.
Chapter
Introduction
Can we feed the world sustainably?
Thijs Bosker, Paul Behrens, and David Ehrhardt
This chapter provides significant contexts on how the human population grew dramatically after two major evolutions: the Agricultural Revolution and the Industrial Revolution. It highlights that population growth among humans has required resources to be diverted from natural systems to human societies, including food, water, and energy. The chapter also explains the Holocene, a period of relative stability in the Earth's climate which enabled population growth. Furthermore, it discusses the Anthropocene, a new geological epoch associated with the global and pervasive impacts of human activities on the environment. The chapter also discusses how ecological footprints are calculated and introduces the concepts of biocapacity, resource stocks, and resource flows. Then it tackles the key environmental and societal challenges related to food production. Lastly, it looks at the role of governance in overcoming sustainability challenges.
Chapter
Abiotic Stresses and How They Affect Crop Yield
Maarten J. Chrispeels
This chapter assesses abiotic stresses such as drought, floods, acidic soils, and soil salinity, and how they affect crop yield. Abiotic stresses cause plant cells to more highly express many genes that help the plant cope with the stress so that growth can continue, albeit at a slower rate. The formation of reactive oxygen species (ROS) is a response to many stresses. ROS damage cells but also serve as signals and cause cells to turn on stress-response genes. The chapter then considers water potential, which is the physical property of water that drives water movement from the soil through the plant and into the atmosphere. It also looks at how some common agricultural practices, other human activities, and climate change are leading to soil degradation and increased abiotic stresses.
Chapter
Sustainable Food Production in the 21st Century
Maarten J. Chrispeels
This chapter discusses sustainable food production in the 21st century. Because virtually all available productive land is already being cultivated, the only way to significantly increase food production is through agricultural intensification: increasing the amount of crop produced per acre. Closing the yield gap, especially on smallholder farms, is essential to feeding humanity. Both breeding better crops through genetics and better agronomic practices are needed to close the yield gap. Research and education at all levels are also necessary. Moreover, all countries need to diminish the amount of food that is spoiled and otherwise wasted. Ultimately, creating a sustainable world will require decreasing the impact of agriculture on climate change.
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