BIODIVERSITY IN AGROECOSYSTEMS - CHAPTER 7 pdf

... 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 ... pools in burned and unburned sagebrush semi-deserts, Ecology, 76 :269– 272 . Hatton, T. J. and West, N. E., 19 87. Early seral trends in plant communities on a surface coal mine in...

Ngày tải lên: 11/08/2014, 17:20

... especially in the rain-fed mixed farming systems of the developing world that will provide an incentive for investment in long-term soil fertility improvements, such as the use of inorganic fertilizers ... that in well-balanced grazing systems, especially those using multispecies, plant biodiversity increases. An exten- sive review of grazing and production data of 236 sites worldwide...

Ngày tải lên: 11/08/2014, 17:20

... 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...

Ngày tải lên: 11/08/2014, 17:20

... 1 0 0 92 95 13 186 15 109 176 20 5 2 13 9 79 11 12 3 51 57 118 119 128 43 1 27 47 FIGURE 7. 2 Scatterplot of dimension 1 against dimension 2 in a simple correspondence analysis of village against researcher-proposed ... efciency Inputs Income/inputs for food crops E 124 (55.11) 0 (0.00) < .001 L 51 (22. 67) 93 (41.33) < .001 Income/inputs for livestock H 39 ( 17. 33) 101...

Ngày tải lên: 18/06/2014, 19:20

... processes (Tilman, 1996), 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 yiel...

Ngày tải lên: 11/08/2014, 17:20

... 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 ... Prostigmata (Actinedida), in Soil Biology Guide, D. L. Dindal, Ed., John Wiley, New York, 6 67 77 8. King, K. L. and Hutchinson, K. J., 1 976 . The effects of sheep stocking inten...

Ngày tải lên: 11/08/2014, 17:20

... Bundesanst. Land Forstwirtsch. Berlin Dahlem, 2 47: 129–1 37. Bosch, J., 19 87. Der Einfluss einiger dominanter Ackerkräuter auf Nutz- and Schadarthro- poden in einem Zuckerrübenfeld, Z. Pflanzenkr. ... dis- coveries for improved activity and perennial sustainment of desired beneficials. Today, high-yielding, high-quality, insect-, disease-, and weed-free monocultures require high-energy inpu...

Ngày tải lên: 11/08/2014, 17:20

... 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...

Ngày tải lên: 11/08/2014, 17:20

... 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...

Ngày tải lên: 11/08/2014, 17:20

... al., 19 87) . 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 ... 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’s...

Ngày tải lên: 11/08/2014, 17:20