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Use and Misuse of Forest-harvested Fruits in the Iquitos Area   总被引:2,自引:0,他引:2  
Abstract: Of 193 fruit species observed to be regularly consumed in the region surrounding Iquitos, Peru, 120 species are exclusively wild-harvested and 19 more originate from both wild and cultivated sources. The wild-harvested fruits of 57 species belonging to 24 different plant families are sold in the Iquitos market and are very important in the economy and diets of the area Nearly half of the Iquitos fruit vendors sell wild-harvested fruits (if fruits used as vegetables or starch sources are excluded), and over half of the fruit species sold are wild-harvested Many fruit species consumed at Iquitos differ from those consumed in other parts of Amazonia Although some native fruit species are beginning to be grown as crops, the wild populations of these high-potential species are being rapidly depleted by destructive harvesting techniques as market pressure begins to build In the last few years, the availability of several of the most popular fruit species has decreased markedly. If nondestructive sustained yield harvesting of resources such as wild-harvested fruits is to play its suggested important role in tropical forest conservation, much stronger efforts will be needed to prevent destructive overharvesting of these potentially significant resources.  相似文献   
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Abstract: Although pollinator declines are a global biodiversity threat, the demography of the western honeybee (Apis mellifera) has not been considered by conservationists because it is biased by the activity of beekeepers. To fill this gap in pollinator decline censuses and to provide a broad picture of the current status of honeybees across their natural range, we used microsatellite genetic markers to estimate colony densities and genetic diversity at different locations in Europe, Africa, and central Asia that had different patterns of land use. Genetic diversity and colony densities were highest in South Africa and lowest in Northern Europe and were correlated with mean annual temperature. Confounding factors not related to climate, however, are also likely to influence genetic diversity and colony densities in honeybee populations. Land use showed a significantly negative influence over genetic diversity and the density of honeybee colonies over all sampling locations. In Europe honeybees sampled in nature reserves had genetic diversity and colony densities similar to those sampled in agricultural landscapes, which suggests that the former are not wild but may have come from managed hives. Other results also support this idea: putative wild bees were rare in our European samples, and the mean estimated density of honeybee colonies on the continent closely resembled the reported mean number of managed hives. Current densities of European honeybee populations are in the same range as those found in the adverse climatic conditions of the Kalahari and Saharan deserts, which suggests that beekeeping activities do not compensate for the loss of wild colonies. Our findings highlight the importance of reconsidering the conservation status of honeybees in Europe and of regarding beekeeping not only as a profitable business for producing honey, but also as an essential component of biodiversity conservation.  相似文献   
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