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1.
Herd mobility is a tool for managing environmental variability in African pastoral systems. This study examines the monthly mobility patterns of 24 herds over six years in the 20,000 ha communal area of Paulshoek, Namaqualand, and assesses the social, economic, and ecological factors affecting the livestock movement of individual herds and all herds combined. When the mobility pattern of all herds was considered, no seasonal or between-year differences in response to rainfall were evident. An analysis of individual herd mobility patterns showed that half of the herds were relatively sedentary over the study period while the other half were regularly mobile. Although herders used mobility to manage their herds in the unpredictable semiarid environment, their daily decisions were often made in response to their social, economic, or personal situations. There was no significant difference in livestock production between herding strategies, but sedentary herders had a greater localized impact on the rangeland than mobile herders. Our analysis suggests that non-environmental factors play a significant role in herd mobility and may consequently affect the efficiency of livestock production and environmental management. 相似文献
2.
The broader ecological and social contexts within which livestock husbandry of Sudano-Sahelian West Africa operates have changed
significantly over the past thirty years. This study concerns how: (1) these broader trends have affected the quantity and
quality of labor investments into livestock herding; and (2) the ecological and animal nutritional implications of observed
variation in labor investments into herding. The study was conducted in a 500 km2 area of western Niger using a combination of qualitative interviews of herders and herd managers, household composition surveys,
herd composition monitoring, grazing management monitoring and georeferenced vegetation and livestock grazing itinerary data.
Statistical analyses were performed using a two-staged approach: (1) analysis of the factors affecting the allocation of labor
to herding at the level of the managing household; and (2) analysis of the effect of herd characteristics, season, microgeography
and herders’ social position on herders’ effort and the nutritional and ecological impacts of these efforts. The results of
these analyses support the conclusion that the changing regional context of livestock husbandry leads to a reduction in labor
(quantity and quality) investment or an “extensification” of herding with significant implications for livestock productivity
and the environment.
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Matthew D. TurnerEmail: |
3.
The Landscape Ecology of Pastoral Herding: Spatial Analysis of Land Use and Livestock Production in East Africa 总被引:2,自引:0,他引:2
Peter B. Coppolillo 《Human ecology: an interdisciplinary journal》2000,28(4):527-560
Understanding landscape-scale patterns of herding is critical in identifying and assessing the impacts of pastoral grazing. Here, a general model of herding is developed based on the Sukuma agropastoral system in the Rukwa Valley, Tanzania. Using this conceptual framework, the factors affecting the maximum distances herds travel from home and the distribution of grazing around pastoral settlements are examined. The distribution of dry season water structured the landscape-scale distribution of grazing throughout the year, not just during the dry season. Water availability strongly affected the distances herds ranged from home in the dry season and the distribution of grazing around pastoral settlements throughout the year. Associations between cattle productivity and herding practices were also examined. The effects of traveling further from home, keeping cattle in large herds, and using/living in areas of high settlement densities were examined on the following measures of productivity: intake rates, foraging behavior, milk yields, and body conditions. Cattle from larger herds were observed to walk more while actively foraging and engage in more walking bouts (taking ten steps without taking a bite). The increased walking of large herds may explain why they range farther from home and highlight the importance and ubiquity of herd splitting among pastoralists. However, herd size effects were not apparent in intake rates or milk yields. Milk yields were negatively affected by traveling farther from home. These data demonstrate substantial variability within herding populations and show interesting similarities with herding systems in substantially more arid areas. 相似文献
4.
Irene Hoffmann 《Human ecology: an interdisciplinary journal》2004,32(1):77-105
In this paper, the link between traditional rights of access to land and water and present day practices is established and illustrated. Data collected during various studies in the Zamfara Forest Reserve, northwest Nigeria, provided information on the different resources utilized (land, pastures, water) and the views and practices of different user-groups and stakeholders. The findings are discussed with a view to improving existing common property resource management (CPRM) in the area. 相似文献
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6.
Kerwin Strauss Alan Brent Sibbele Hietkamp 《The International Journal of Life Cycle Assessment》2006,11(3):162-171
Goal and Background Current Life Cycle Impact Assessment (LCIA) procedures have demonstrated certain limitations in the South African manufacturing industry. The aim of this paper is to propose new characterisation and normalisation factors for classified mined abiotic resource depletion categories in the South African context. These factors should reflect the importance of mined resources as they relate to region-specific resource depletion. The method can also be applied to determine global factors. Methods The reserve base (as in 2001) of the most commonly produced minerals in South Africa is used as basis to determine characterisation factors for a non-renewable mineral resources category. The average production of these minerals from 1991 to 2000 is compared to economically Demonstrated and Demonstrated Marginal Reserves (and not ultimate reserves) to obtain the characterisation factors in equivalence units, with platinum as the reference mineral. Similarly, for a non-renewable energy resources category, coal is used in South Africa as equivalent unit as it is the most important fossil fuel for the country. Crude oil and natural gas resources are currently obtained from reserves elsewhere in the world and characterisation factors are therefore determined using global resources and production levels. The normalisation factors are based on the total economic reserves of key South African minerals and world non-renewable energy resources respectively. A case study of the manufacturing of an exhaust system for a standard sedan is used to compare LCIA results for mined abiotic resource categories that are based on current LCIA factors and the new South African factors. Results and Discussion The South African LCIA procedure differs from current methods in that it shows the importance of other mined resources, i.e. iron ore and crude oil, relative to PGMs and coal for the manufacturing life cycle of the exhaust system. With respect to PGMs, the current characterisation factors are based on the concentrations of the metals in the ores and the ultimate reserves, which are erroneous with respect to the actual availability of the mineral resources and the depletion burden placed on these minerals is consequently too high. Conclusions The South African LCIA procedure for mined abiotic resources depletion shows the significance of choosing a method, which is inline with the current situation in the mining industry and its limitations. Recommendations and Outlook It is proposed to similarly investigate the impacts of the use of other natural resource groups. Water, specifically, must receive attention in the characterisation phase of LCIAs in South African LCAs. 相似文献