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In the context of ecosystem approach to fisheries, it is a critical issue to build management tools able to predict the possible trajectories of ecosystems under various human pressure or environmental variations, but also capable to point out influent and sensitive components. 相似文献
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Socioeconomic indicators and the survival of the tropical rainforest of cross river state of Nigeria
An internal household survey of socioeconomic indicators in the Cross River State forest communities showed that basic infrastructural
facilities such as clean water supply, adequate waste disposal system, good roads and electricity are grossly inadequate.
There is a total absence of modern family planning practices in the communities, and population is projected to increase by
44.8% between 2000 and 2015 and 85.4% between 2000 and 2025. The study revealed that about 65% of the population of the rainforest
communities consists of subsistence farmers and power chain operators, and besides the 19% of the Cross River State Tropical
High Forestry (THF) already reported to have been lost to agriculture and plantation between 1972 and 1991, about 9% was lost
between 1991 and 2000. An additional 25% of the THF will be lost by 2025, leaving only 470600 hectares (4706 km2). With 84.1% of community members having an annual income less than $300, the survival potential of the Cross River State
rainforest in the next fifty years is very low, unless an effective forest management programme is encouraged by government
in partnership with all stakeholders. 相似文献
135.
Gail Stetten Ph.D. Karin J. Blakemore Anne M. Courter Cathleen A. Coss Ethylin Wang Jabs 《黑龙江环境通报》1992,12(2):83-91
In situ hybridization using a series of alphoid DNA probes has demonstrated the origin of two small accessory mosaic marker chromosomes ascertained from 1079 amniocenteses. These markers appeared to be de novo, derived from acrocentric chromosomes, and identical by traditional cytogenetic staining (G, Q, C, AgNOR, Hoechst-distamycin). Molecular characterization showed that one marker had originated from chromosome 14, the other from chromosome 22. Clinical outcome in both cases was normal. 相似文献
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