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Gap Analysis of Conserved Genetic Resources for Forest Trees   总被引:1,自引:0,他引:1  
Abstract:  We developed a gap analysis approach to evaluate whether the genetic resources conserved in situ in protected areas are adequate for conifers in western Oregon and Washington (U.S.A.). We developed geographic information system layers that detail the location of protected areas and the distribution and abundance of each tree species (noble fir [ Abies procera Rehd.] and Douglas-fir [ Pseudotsuga menzeisii Mirb.]). Distribution and abundance were inferred from available spatial data showing modeled potential and actual vegetation. We stratified the distribution of each species into units for genetic analysis using seed and breeding zones and ecoregions. Most strata contained at least 5000 reproductive-age individuals in protected areas, indicating that genetic resources were well protected in situ throughout most of the study region. Strict in situ protection was limited, however, for noble fir in the Willapa Hills of southwestern Washington. An in situ genetic resource gap arguably occurred for Douglas-fir in the southern Puget lowlands, but this gap was filled by extensive ex situ genetic resources from the same region. The gap analysis method was an effective tool for evaluating the genetic resources of forest trees across a large region.  相似文献   
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This paper documents the culture‐specific understanding of social capital among Haitians and examines its benefits and downsides in post‐disaster shelter recovery following the 12 January 2010 earthquake. The case study of shelter recovery processes in three socioeconomically diverse communities (Pétion‐Ville, Delmas and Canapé Vert) in Port‐au‐Prince suggests that social capital plays dual roles in post‐disaster shelter recovery of the displaced population in Haiti. On the one hand, it provides enhanced access to shelter‐related resources for those with connections. On the other hand, it accentuates pre‐existing inequalities or creates new inequalities among displaced Haitians. In some cases, such inequalities lead to tensions between the have and have‐nots and instigate violence among the displaced.  相似文献   
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Efficiency of pretreatment as foliar spray of indole-3-acetic acid, gibberellic acid and kinetin (6-furfuryl aminopurine) each ranging from 10(-7) to 10(-5) M in restoring the metabolic alterations imposed by NaCl salinity (E.C. value 4.0 m mhos/cm) was investigated in Vigna radiata (L.) Wilczek. Application of NaCl resulted in about 7% and 9% decrease in phenol content in mung bean leaf and root respectively. In leaf, NaCl caused 40% increase in polyphenol oxidase enzyme activity over the control set. This effect was accentuated in root, where salinity caused 200% increase in the enzyme activity. In leaf and root of mung-bean plant, ascorbic acid content decreased about 29% and 31% respectively under salinity stress as compared with control. Ascorbic acid oxidase enzyme activity increased under stress by about 55% and 23% respectively in leaf and root. It was noted that all the three growth regulators used in the present study were able to overcome to variable extents the adverse effects of stress imposed by NaCl solution.  相似文献   
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