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101.
Outreach nurseries are favored conservation and social forestry tools globally, but, as with many integrated conservation
and development programs (ICDPs), they do not always produce anticipated results. A synopsis of the experience of South African
practitioners is provided in this study of 65 outreach nurseries. South African outreach nurseries frequently include financial
objectives, creating additional challenges in simultaneously attaining conservation and socioeconomic goals. Progress was
hindered by biophysical problems (e.g., lack of water, poor soils, etc.) as well as the harsh socioeconomic conditions facing
most communities in which nurseries had been established. Attaining financial viability was challenging. Business management
skills were often restricted, and few viability studies included adequate market research. Costs to community participants
were usually high, and benefits were limited. Conservation objectives were frequently lost in the struggle to attain financial
viability. The management of social processes also proved challenging. Although small scale and relatively straightforward
compared with many ICDPs, nurseries usually require substantial institutional support, including a range of technical, business,
and development services. Project time frames need to be reconsidered, as practitioners estimate that it takes 5–10 years
for nurseries to start meeting objectives, and donors and implementing agencies often operate on 2–3-year project cycles.
Detailed viability studies are essential, incorporating a social probe and an assessment of potential impacts of projects
on community participants. Progress needs to be continuously evaluated to enable institutions and community participants to
adapt to changing conditions as well as ensure that the spectrum of objectives are being achieved. 相似文献
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Fish were collected at regular intervals over 5 yr (February 1977 to December 1981) from ten shallow-water sites located throughout the lower, middle and upper regions of the large Swan Estuary in temperate southwestern Australia. Analysis of the catch data showed that the total number of species and total density of fishes were both influenced to a greater extent by site and season within the estuary than by year. The number of species and density of fishes within the whole system were greatest during the summer and autumn, when salinities and temperatures were at a maximum, and declined with distance from the estuary mouth. This reflects the trends shown by marine species, which comprise many species that occur only occasionally in the estuary (marine stragglers) and others which enter estuaries regularly and in considerable numbers (marine estuarine-opportunists). The density of marine estuarine-opportunists was also correlated with temperature, reflecting the tendency for the species of this category to congregate in the shallows during the summer and autumn. The similar seasonal aggregations of the single anadromous species and representatives of species that complete their whole life cycle in the estuary were frequently related to spawning. The density of the estuarine category was correlated neither with salinity nor distance from the estuary mouth. The number of estuarine species was also not correlated with distance from the estuary mouth. The density of freshwater species was inversely correlated with salinity and positively correlated with distance from the estuary mouth. The composition of the fish fauna changed progressively through the estuary, with that of the lower estuary being the most discrete. The composition also changed seasonally, particularly in the upper estuary where, during the winter and spring, the volume of freshwater discharge increased greatly and as a consequence the salinity declined markedly. The species diagnostic of the lower estuary were generally marine estuarine-opportunists, whereas those of the upper estuary typically belonged to either the estuarine or anadromous categories. The marine estuarine-opportunistMugil cephalus was, however, also one of the diagnostic species in the upper estuary during the winter and spring.Please address all correspondence and requests for reprints to I. C. Potter at Murdoch University 相似文献
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A more positive environmental outlook 总被引:1,自引:1,他引:0
John F. Potter 《The Environmentalist》1994,14(2):81-83
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