Managing Biodiversity in Agricultural Ecosystems

Managing Biodiversity in Agricultural Ecosystems

D. I. JARVIS
C. PADOCH
H. D. COOPER
Copyright Date: 2007
Pages: 512
https://www.jstor.org/stable/10.7312/jarv13648
  • Cite this Item
  • Book Info
    Managing Biodiversity in Agricultural Ecosystems
    Book Description:

    Published in three other languages and growing, Managing Biodiversity in Agricultural Ecosystems takes a look at how farmers manage, maintain, and benefit from biodiversity in agricultural production systems. The volume includes the most recent research and developments in the maintenance of local diversity at the genetic, species, and ecosystem levels. Chapters cover the assessment and farmer management practices for crop, livestock, aquatic, and associated diversity (such as pollinators and soil microorganisms) in agricultural ecosystems; examine the potential role of diversity in minimizing pest and disease pressures; and present studies that exemplify the potential nutritional, ecosystem service, and financial values of this diversity under changing economic and environmental conditions. The volume contains perspectives that combine the thinking of social and biological scientists.

    Inappropriate or excessive use of inputs can cause damage to biodiversity within agricultural ecosystems and compromise future productivity. This book features numerous case studies that show how farmers have used alternative approaches to manage biodiversity to enhance the stability, resilience, and productivity of their farms, pointing the way toward improved biodiversity on a global scale. As custodians of the world's agricultural biodiversity, farmers are fully invested in ways to create, sustain, and assist in the evolution and adaptation of a variety of plant and animal species. Thus this text is mandatory reading for conservationists, environmentalists, botanists, zoologists, geneticists, and anyone interested in the health of our ecosystem.

    eISBN: 978-0-231-51000-4
    Subjects: Environmental Science, Ecology & Evolutionary Biology

Table of Contents

  1. Front Matter
    (pp. i-vi)
  2. Table of Contents
    (pp. vii-x)
  3. Acknowledgments
    (pp. xi-xii)
  4. Contributors
    (pp. xiii-xx)
  5. 1 Biodiversity, Agriculture, and Ecosystem Services
    (pp. 1-12)
    D. I. JARVIS, C. PADOCH and H. D. COOPER

    Biodiversity in agricultural ecosystems provides our food and the means to produce it. The variety of plants and animals that constitute the food we eat are obvious parts of agricultural biodiversity. Less visible—but equally important—are the myriad of soil organisms, pollinators, and natural enemies of pests and diseases that provide essential regulating services that support agricultural production. Every day, farmers are managing these and other aspects of biological diversity in agricultural ecosystems in order to produce food and other products and to sustain their livelihoods. Biodiversity in agricultural ecosystems also contributes to generating other ecosystem services such as...

  6. 2 Measuring, Managing, and Maintaining Crop Genetic Diversity On Farm
    (pp. 13-33)
    A. H. D. BROWN and T. HODGKIN

    The great challenge now facing the global agricultural community is how to develop and improve the productivity of agricultural ecosystems to alleviate poverty and ensure food security in a sustainable fashion. For meeting short-term needs and achieving long-term sustainability, it is universally recognized that plant genetic diversity is essential.

    Management of biodiversity is complex and synthetic, involving all levels of diversity (ecosystem, species, gene, and environment), and depends on a variety of disciplines (genetics, farming systems, social sciences). Does genetic diversity itself merit any special focus or concern amid these disciplines? We contend that it does.

    If so, then we...

  7. 3 Variety Names: An Entry Point to Crop Genetic Diversity and Distribution in Agroecosystems?
    (pp. 34-76)
    M. SADIKI, D. JARVIS, D. RIJAL, J. BAJRACHARYA, N. N. HUE, T. C. CAMACHO-VILLA, L. A. BURGOS-MAY, M. SAWADOGO, D. BALMA, D. LOPE, L. ARIAS, I. MAR, D. KARAMURA, D. WILLIAMS, J. L. CHAVEZ-SERVIA, B. STHAPIT and V. R. RAO

    The names farmers give to their traditional varieties or landraces are fundamental to their very essence and use. Harlan (1975) discusses how landraces are recognizable morphologically, farmers have names for them, and different landraces are understood to differ in adaptation to soil type, time of seeding, date of maturity, height, nutritive value, use, and other properties. Many studies have pointed out how farmers recognize and name populations of the crops they grow according to their agromorphological, ecological-adaptive, quality, and use characteristics (Boster 1985; Quiros et al. 1990; Bellon and Brush 1994; Teshome et al. 1997; Schneider 1999; Soleri and Cleveland...

  8. 4 Seed Systems and Crop Genetic Diversity in Agroecosystems
    (pp. 77-116)
    T. HODGKIN, R. RANA, J. TUXILL, D. BALMA, A. SUBEDI, I. MAR, D. KARAMURA, R. VALDIVIA, L. COLLADO, L. LATOURNERIE, M. SADIKI, M. SAWADOGO, A. H. D. BROWN and D. I. JARVIS

    In the last century, national governments have devoted major resources to modernizing their agricultural sectors, including the development and dissemination of improved crop varieties. Despite this extensive effort, the majority of rural farming communities in developing countries continue to use traditional or informal sources of seeds or vegetative planting materials (Gaifani 1992; Hardon and de Boef 1993; Tripp 2001). Either they save their own seed or they obtain seed from friends, relatives, neighbors, or local markets. In an informal system, seeds may be acquired via cash transactions, by barter, as gifts, through exchange of one variety of seed for another,...

  9. 5 Measures of Diversity as Inputs for Decisions in Conservation of Livestock Genetic Resources
    (pp. 117-140)
    J. P. GIBSON, W. AYALEW and O. HANOTTE

    More than 6,379 documented breed populations of some 30 species of livestock have been developed in the 12,000 years since the fi rst livestock species were domesticated (Scherf 2000). These breeds have evolved adaptations that allow livestock production in a wide range of situations, including some of the most stressful natural environments inhabited by humans. These naturally evolved genetic characteristics provide a coherent basket of sustainable options for disease resistance, survival, and efficient production that have often been ignored in the drive to find technological and management solutions to individual problems of livestock production in low-input systems. It is estimated...

  10. 6 Management of Farm Animal Genetic Resources: Change and Interaction
    (pp. 141-180)
    I. HOFFMANN

    Breeds of domesticated farm animal species are the biological basis for livestock sector development and for its contribution to food security and sustainable rural development. Only 14 of the approximately 30 domesticated mammalian and bird species provide 90% of human food supply from animals, yet the value of most animal genetic resources is poorly understood. Development in the 20th century has concentrated on a very small number of breeds worldwide, often without due consideration of the effects of the local production environment on a breed’s ability to survive, reproduce, and produce. The management of this biological capital has been neglected,...

  11. 7 Aquatic Biodiversity in Rice-Based Ecosystems
    (pp. 181-199)
    M. HALWART and D. BARTLEY

    The cultivation of most rice crops in irrigated, rainfed, and deepwater systems offers a suitable environment for fish and other aquatic organisms (figure 7.1). More than 90% of the world’s rice, equivalent to approximately 134 million ha (figure 7.2), is grown under flooded conditions, not only providing home to a wide range of aquatic organisms but also offering opportunities for their enhancement and culture. Aquatic production, in addition to the rice crop itself, is a critically important resource for rural livelihoods in developing countries. Local consumption and marketing are particularly important for food security because aquatic food resources are the...

  12. 8 Pollinator Services
    (pp. 200-223)
    P. G. KEVAN and V. A. WOJCIK

    Herbivores, predators, parasitoids, parasites, and pathogens are understood ecologically as crucial to sustaining ecosystems and their diversity. Nevertheless, just as important are the mutualistic relationships. Pollination is the hub of a multispoke productivity wheel that has all consumers—humans, livestock, and wildlife—at the rim (figure 8.1). Ecological interactions and complexity now are within the domain of conservation and sustainability. The biodiversity of the world’s dominant flora (flowering plants) and dominant fauna (insects) are so intimately and coevolutionarily enmeshed through pollination that the erosion of the processes has serious environmental consequences. Indeed, pollination is now regarded as a jeopardized ecosystem...

  13. 9 Management of Soil Biodiversity in Agricultural Ecosystems
    (pp. 224-268)
    G. G. BROWN, M. J. SWIFT, D. E. BENNACK, S. BUNNING, A. MONTÁÑEZ and L. BRUSSAARD

    Soil is not just an agglomeration of a little organic matter and mineral particles with ions that can be used by plants. It is a living entity and the home of countless organisms whose diversity may even surpass that of those living above ground, outside the soil.

    Soil systems contain among the most diverse yet disparate assemblages of organisms on Earth (Brussaard et al. 1997; Giller et al. 1997; Wall and Moore 1999). These organisms have a broad range of body sizes, feeding strategies, and life habits, from strictly aquatic to obligatorily terrestrial (Bater 1996). They range in size from...

  14. 10 Diversity and Pest Management in Agroecosystems: Some Perspectives from Ecology
    (pp. 269-291)
    A. WILBY and M. B. THOMAS

    At a time when biodiversity is being lost at an unprecedented rate because of human activity, much research effort has been spent on assessing the importance of biodiversity for the functioning and stability of ecosystems and for the delivery of ecosystem services. Pest control has been identified on numerous occasions as a valuable ecosystem service delivered by biodiversity (Pimentel 1961; Horn 1988; Altieri 1991; Mooney et al. 1995a, 1995b; Naylor and Ehrlich 1997; Naeem et al. 1999; Schläpfer et al. 1999), one that is at risk from human activity (Naylor and Ehrlich 1997). There is much evidence that as agricultural...

  15. 11 Managing Crop Disease in Traditional Agroecosystems Benefits and Hazards of Genetic Diversity
    (pp. 292-319)
    D. I. JARVIS, A. H. D. BROWN, V. IMBRUCE, J. OCHOA, M. SADIKI, E. KARAMURA, P. TRUTMANN and M. R. FINCKH

    For millennia, farmers have contended with pest and disease outbreaks that threaten their crops and livelihoods. Their legacy of domesticated varieties or landraces is notably diverse genetically, both between and within populations. The question that naturally arises is whether the maintenance of diversity on farm, particularly for genes that affect host–pathogen interactions, has given farmers an effective strategy against disease, or, conversely, whether it has provided the opportunity for the evolution of adverse diversity in pathogen populations. In other words, is crop genetic diversity a benefit in reducing disease in time, or is it a hazard in giving scope...

  16. 12 Crop Variety Diversification for Disease Control
    (pp. 320-337)
    Y. Y. ZHU, Y. Y. WANG and J. H. ZHOU

    Current modern agricultural practices with high input and high output have played a tremendously important role in enhancing rice productivity to meet the increasing food demands and have contributed significantly to food security in China (Lu 1996a, 1996b).

    Yet this intensive cultivation, most commonly of a few improved highyielding varieties on extensive rice farming land, and the long-term application of excessive amounts of chemical fertilizers and pesticides have severely deteriorated the rice ecological systems, rendering agricultural production environments vulnerable. As a result, the occurrence of diseases has become more common and the evolution of pathogens more rapid. The cycles of...

  17. 13 Managing Biodiversity in Spatially and Temporally Complex Agricultural Landscapes
    (pp. 338-361)
    H. BROOKFIELD and C. PADOCH

    Farmers manage biodiversity. At one extreme, they may minimize it by planting thousands of hectares to a chemically enhanced and protected single crop or, at the other, create a diverse landscape of patches under multiple crops and trees interspersed with edges and woodlots. This chapter departs significantly from the subject matter of the preceding chapters. It is about biodiversity management at the scale of whole farms and farming regions, including not only agrobiodiversity but also natural and other managed biodiversity.

    This chapter also views biodiversity in agricultural landscapes at a somewhat broader temporal scale. By rotating crops and modifying and...

  18. 14 Diversity and Innovation in Smallholder Systems in Response to Environmental and Economic Changes
    (pp. 362-381)
    K. RERKASEM and M. PINEDO-VASQUEZ

    In a world where most agricultural products are industrially produced, smallholder farmers in the tropics are among the few groups that are still planting and managing a great diversity of crops and other biological resources in their landholdings. Experts have identified the most rare species and varieties of crops in small farmers’ fields, and they have called for their preservation. The dangers posed to world agriculture by the loss of the diversity of crops and the flexibility they offer are well known, and programs to conserve these priceless resources in situ and ex situ have been established. However, based on...

  19. 15 Agrobiodiversity, Diet, and Human Health
    (pp. 382-406)
    T. JOHNS

    Plant biodiversity is essential to human health. Plants provide both nutrients and medicinal agents, form components of robust ecosystems, and contribute to sociocultural well-being. Traditional values and scientific conceptions concur on the necessity of dietary diversity, particularly of fruits and vegetables, for health. In the face of economic and environmental changes, increased simplification of the diets of large numbers of people to a limited number of high-energy foods presents unprecedented obstacles to health. Cultural knowledge of the properties of plants erodes at the same time. Conservation of biodiversity and the knowledge of its use therefore preserves the adaptive lessons of...

  20. 16 Comparing the Choices of Farmers and Breeders: The Value of Rice Landraces in Nepal
    (pp. 407-425)
    D. GAUCHAN and M. SMALE

    Nepal is an important center of diversity for Oryza sativa (“Asian” rice). Asian rice probably was first cultivated in the geographically and culturally diverse region extending from Nepal to northern Vietnam (Vaughan and Chang 1992). Farmers’ rice varieties (referred to here as landraces) still occupy more than 30% of the total cultivated rice area in Nepal (apsd 2001). These are typically more heterogeneous than the modern varieties that are bred for uniformity in stature and selected on the basis of particular performance criteria, and they are often adapted to specific local human needs and environmental niches (Simmonds 1979). An estimated...

  21. 17 Economics of Livestock Genetic Resources Conservation and Sustainable Use: State of the Art
    (pp. 426-445)
    A. G. DRUCKER

    Livestock supply some 30% of the total human requirements for food and agriculture (fao 1999), and some 70% of the world’s rural poor depend on livestock as a component of their livelihoods (Livestock in Development 1999). Animal genetic resource (AnGR) diversity thus contributes in many ways to human survival and well-being, with differing animal characteristics and hence outputs being tailored to suit a variety of local community needs.

    However, an estimated 16% of these uniquely adapted breeds, bred over thousands of years of domestication in a wide range of environments, have been lost since the beginning of the 19th century...

  22. 18 Ecological and Economic Roles of Biodiversity in Agroecosystems
    (pp. 446-472)
    M. CERONI, S. LIU and R. COSTANZA

    As ecosystems become less diverse as a consequence of land conversion and intensification, there is a shared concern over the functioning of these systems and their ability to provide a continuous flow of services to human societies (Ehrlich and Wilson 1991). The ecological consequences of biodiversity loss on ecosystem functioning have been investigated for more than a decade, but only recently has interest developed around the consequences of agricultural biodiversity loss on the functions of agroecosystems. Agricultural intensification has led to a widespread decline in agricultural biodiversity measured across many different levels, from a reduction in the number of crop...

  23. Index
    (pp. 473-492)