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Household firewood use has become increasingly popular in the United States over the past few years. Significant problems remain in estimating firewood consumption. Methods of determining the amount of wood consumed vary from state to state. Units used for measuring firewood vary, but the cord remains the researcher's favorite. Factors used for converting other units, such as pickup truck loads to cords also vary. People who do not use firewood are less likely to respond to mailed surveys, resulting in potential overestimates of statewide consumption. This paper identifies some problems associated with estimating household firewood consumption and recommends methods of dealing with them. 相似文献
2.
Municipal commonages surround many small towns throughout South Africa, and are an integral component of the national land reform programme. But little is known about their extent, use or value, and most appear to have limited or no management or investment. This paper reports on a survey of randomly selected households in three small towns in the Eastern Cape to ascertain the extent and purpose of use of municipal commonages. Between 27% and 70% of urban households used commonage depending on site. Key resources used were fuelwood, medicinal plants, and grazing of livestock. Typically, commonage using households were poorer and less educated than other urban residents, although the profile of users is unique for each town. Given the extensive use of commonage resources, and their contribution to the livelihoods of the poor, local municipalities need to develop and implement sound management strategies that account for all users of commonages, rather than the oft encountered focus on livestock owners and production. 相似文献
3.
Eric L. Hyman 《Environmental management》1994,18(1):23-32
Fuelwood consumption in Northern Nigeria exceeds the sustainable production, and the deficit is currently met through long-distance
transport from the southern part of the country at an artificially low cost Current household fuel consumption patterns and
factors affecting stove choice are discussed. Little has been done to promote more efficient woodstoves in the region, but
prospects for stove programs are only good where fuelwood is marketed and the policy environment is conducive.
At subsidized official prices for kerosene, liquefied petroleum gas (LPG), and electricity, wood is more expensive on a net
usable heat basis, but the high capital cost of stoves for these fuels prevents many households from switching. Moreover,
these fuels are often only available at much higher parallel market prices, which result in wood being the less expensive
choice. There is little prospect for substitution of coal, solar cookers, or biogas digesters. 相似文献
4.
In China, many rural communities depend upon forests to provide wood, fuel, fertilizer, animal bedding, and valuable non-timber
forest products (NTFP). However, the degree to which forest resource extraction is compatible with new conservation aims is
unclear because there is little information on the specific ecological effects of traditional forest collecting practices.
Therefore, we compared the structure and floristics of Pinus densata forests exposed to three levels of resource extraction by Tibetan villages in northwest Yunnan: (1) a forest site protected
from wood and timber removal, (2) moderately utilized forest sites exposed to traditional collecting practices, and (3) patches
of highly utilized forest from which timber extraction is high in response to recent development pressures. The results show
that understorey and cryptogamic species are reduced in all the utilized forest sites by comparison with the protected forest.
However, the moderately utilized pine forests still provide good NTFP habitats by maintaining relatively high canopy covers,
litter covers, and understorey structural complexity; this suggests that traditional forest resource use, while simplifying
the forest, does not pose an increasing threat to pine forest integrity. By comparison, the highly utilized forests are transformed
into open, herb-rich environments in which canopy covers and understorey complexity are depleted, and NTFP habitats are degraded.
In the future it may be practical to enhance biodiversity by proscribing forest resource collection, but the immediate priority
is to monitor the sustainability of forest utilization using indicators such as understorey development, litter cover, and
cryptogamic richness. 相似文献
5.
Hans Schreier Sandra Brown George Kennedy Pravakar B. Shah 《Environmental management》1991,15(6):815-822
A GIS-based land evaluation model was developed to determine the food, feed, and fuelwood sufficiency of all districts in
Nepal. Resource surpluses or deficits were calculated for each district for 1981, the year for which the national land resource
data were available. Of the three resources, feed supplies were found to be the most critical. Feed deficits occurred in 57%
of all districts in 1981, while food and fuelwood deficits occurred in less than 10% of all districts. Different scenarios
were carried out for the year 2000 to estimate the magnitude of future resource deficits, assuming resource use and yields
in Nepal remain constant in the face of growing population and livestock numbers. Linking resource data with spreadsheet and
GIS systems provides a new way to understand and evaluate resources at the district and national levels. To more fully capture
the usefulness of this approach, information on rates of change in productivity and land use is needed. 相似文献
6.
John J. Metz 《Environmental management》1994,18(3):371-390
This paper describes forest product use at Chimkhola, an upper elevation village of west central Nepal. Villagers have large
herds of livestock that they use to fertilize agricultural fields by holding the animals on cropland for one to several weeks
prior to planting. Herds are moved sequentially from one group of fields to another until all are planted, and then families
take animals into the forests. Herders, therefore, live in temporary shelters away from the homestead throughout the year,
and for much of the year feed their livestock fodder cut from forest trees. By combining repeated interviews of sample households,
one-time interviews with a large sample of village families, and direct measurements of forest products being used, I found
that livestock maintenance consumes 74% of the hand-harvested wild biomass: 26.4% for green fodder, 32.3% for fuelwood at
the herder's hut, and 13.8% for construction of the herder's hut. Fuelwood burned at the homestead is the next largest consumer,
17.6%. Villagers also use small amounts of forest materials for house construction, charcoal, agricultural implements, and
bamboo for baskets and mats. The large amounts used by herders and livestock at Chimkhola mean that wild vegetation use there
far exceeds the measurements made by previous reliable studies at other communities. This system of forest use is, however,
degrading Chimkhola's forests and gradually converting them to shrublands. 相似文献
7.
Agricultural intensification within agroforestry: The case of coffee and wood products 总被引:1,自引:0,他引:1
Compared to the environmental and conservation value as refuges for biodiversity, less is known about the social and economic value of shaded coffee systems. The agroforestry system can serve as a source of non-coffee products for diverse purposes. This study focuses on the role of shade trees in smallholder coffee farms, examining the wood products derived from the shaded coffee system. Data presented from surveys with 185 growers in Peru and 153 growers in Guatemala show that the consumption and sale of all non-coffee products account for a fifth to a third of the total value realized from the agroforestry system. Fuelwood and construction materials account for much of this value. Differences seen between countries can be traced to agricultural intensification – the degree to which the coffee agroforestry system is “technified” (i.e., managed with a reduced shade tree cover and diversity, high-yielding cultivars, agrochemical inputs, etc.) – as well as the relative demand for wood resources and farmers’ access to natural forest systems. 相似文献
8.
Himraj Dang 《Environmental management》1993,17(3):283-288
Deforestation and decline in agricultural productivity are major concerns over large parts of sub-Saharan Africa. One of the
principal causes for both these phenomena is the export of woodfuels from rural agroecosystems to urban markets. This process
is noteworthy because of the size of the trade. Wood fuels (fuelwood, charcoal, and agricultural residues) constitute the
most important source of energy in these countries, varying from 60% to 95% of total energy consumption. In terms of the environmental
impact of the fuelwood trade, solutions typically considered are the introduction of improved cookstoves, fuelwood plantations,
and fuel substitution by conventional fuels. This article examines the structure of the fuelwood problem, reviews the successes
and failures of past experiences, and focuses on the potential for fuel substitution as an option to reduce the urban demand
for fuelwood. 相似文献
9.
Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed. 相似文献
10.
Resource consumption in developing countries has been the focus of a considerable amount of research. What has been understudied however, has been the feedback affects of resource consumption on resource availability to both households and communities. Heavy reliance on natural resources and intensive smallholder agriculture common to many rural communities in developing countries has forced people to fulfill short-term needs to the detriment of long-term ecological and livelihood sustainability. This paper introduces a conceptual framework to examine how individuals and households fulfill daily caloric needs and the aggregate effects on resource availability and consumption. Data were collected from a large number of published case studies of rural land-use dynamics, growth and yield models, and human livelihoods were reviewed from scientific journals, reports published by NGOs, and government reports. Using inputs defined by the user, the model tracks annual fuelwood and agricultural land use based on meeting individual energy demands. A case-study-based analysis was patterned after smallholder agriculturalists at the family and community level. Three scenarios are presented in this paper using data from Uganda to illustrate the application of this model. 相似文献
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