BIODIVERSITY IN AGROECOSYSTEMS - CHAPTER 6 pdf

... Cereal World 60 –93 49 65 Developed 17–18 19–33 Developing 123–2 06 68–91 Sub-Saharan 141–194 1 36 161 Latin America 76 105 53–77 West Asia and North Africa 104–157 74–100 Rest of Asia 148–255 64 –85 © ... that in well-balanced grazing systems, especially those using multispecies, plant biodiversity increases. An exten- sive review of grazing and production data of 2 36 sites worldw...

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... also increases in abundance following exces- sive livestock grazing in the spring (West and Young, 1998). Livestock grazing also reduces the chance of fires by removal of fine fuels in the interspaces ... surface coal mine in southwestern Wyoming, Vegetatio, 73:21–29. Haws, B. A., 1987. The status of IPM strategies for controlling grass bugs infesting introduced grassland monocultures,...

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... already using. Sperling et al. (1993) successfully involved farmers in Rwanda in breeding and selecting segregating populations of beans. Integration of formal and informal breeding efforts are increasing ... CHAPTER 14 Conserving and Using Crop Plant Biodiversity in Agroecosystems Wanda W. Collins and Geoffrey C. Hawtin CONTENTS Introduction Sources of Genetic Diversity in Crop...

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... processes (Tilman, 19 96) , maintaining and increasing protozoan biodiversity will contribute to more sustainable agriculture. Ecofarming and organic fertilizer management enhance pro- tozoan activity. Protozoa ... through burrowing move- ments and passing ingested cysts through guts, providing new hot spots and releasing greater quantities of nutrients, which have led to increased plant yi...

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... role in the binding of pesticides in soil. Fulvic and humic acids are most commonly involved in binding interactions. Pesticides or their degradation intermediates can also be polymerized or incorporated ... Orchesella cincta. The lethal concentration (LC 50 ) for atrazine was estimated at 224 µg/g atrazine in food. Mortality and molting frequency increased with increasing concentrati...

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... beneficials. Today, high-yielding, high-quality, insect-, disease-, and weed-free monocultures require high-energy inputs to produce and harvest. With production costs escalating, interest in enduring and efficient ... Insects and Their Value Biodiversity Crisis Biodiversity in Farmland Biodiversity Monitoring Key Beneficials in Agroecosystems Intraspecific Diversity of Beneficials...

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... Nicholls CONTENTS Introduction The Nature and Function of Biodiversity in Agroecosystems Patterns of Insect Biodiversity in Agroecosystems Plant Biodiversity and Insect Stability in Agroecosystems Patterns ... FUNCTION OF BIODIVERSITY IN AGROECOSYSTEMS Biodiversity refers to all species of plants, animals, and microorganisms existing and interacting within an ecosyst...

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... agricultural sustainability and its measurement in small-scale farming in sub-Saharan Africa, Ecol. Econ., 11:105–125. © 1999 by CRC Press LLC. CHAPTER 8 Agroforestry for Biodiversity in Farming Systems Roger ... Kenya. Ingram, J., 1990. The role of trees in maintaining and improving soil productivity — a review of the literature, in Agroforestry for Sustainable Production: Econ...

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... 1987). Breeding in western North America during the boreal summer, Swainson’s hawks migrate to the nonbreeding grounds in South America with the advancing austral summer, maintaining both climatic ... made illegal in Argentina. An ecotoxicology program was initiated, with field and labo- ratory training for government agents, students, and veterinarians living in the Figure 2 Swainson’...

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... 1) in the climax stage of succession (Odum, 1 969 ). An increase in physical (inorganic) materials in urban systems coincides with a decreasing P/R ratio (i.e., a significant increase in main- tenance ... diversity in terms of maintaining wild or native species populations. Increased biodiversity at the landscape level (in the form of increased habitat or agroecosystem diversity)...

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