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991.
There is a fundamental divergence of opinion between the EU and the US over how food products derived from genetically modified organisms should be labeled. This has less to do with safety, as moves towards the international harmonization of safety standards continue apace, and rather more to do with the consumers' right to know about the origins of the food they are consuming. This paper uses a framework drawn from the global public goods (GPG) literature of economics and the work by international relations theorists on formal international organizations (FIO) to explain why there is presently no global consensus on the manner (voluntary or mandatory) in which GM food products should be labeled.  相似文献   
992.
Tradable biodiversity credit systems provide flexible means to resolve conflicts between development and conservation land-use options for habitats occupied by threatened or endangered species. We describe an approach to incorporate the influence of habitat fragmentation into the conservation value of tradable credits. Habitat fragmentation decreases gene flow, increases rates of genetic drift and inbreeding, and increases probabilities of patch extinction. Importantly, tradable credit systems will change the level of fragmentation over time for small and/or declining populations. We apply landscape equivalency analysis (LEA), a generalizable, landscape-scale accounting system that assigns conservation value to habitat patches based on patch contributions to abundance and genetic variance at landscape scales. By evaluating habitat trades using two models that vary the relationship between dispersal behaviors and landscape patterns, we show that LEA provides a novel method for limiting access to habitat at the landscape-scale, recognizing that the appropriate amount of migration needed to supplement patch recruitment and to offset drift and inbreeding will vary as landscape pattern changes over time. We also found that decisions based on probabilities of persistence alone would ignore changes in migration, genetic drift, and patch extinction that result from habitat trades. The general principle of LEA is that habitat patches traded should make at least equivalent contributions to rates of recruitment and migration estimated at a landscape scale. Traditional approaches for assessing the “take” and “jeopardy” standards under the Endangered Species Act based on changes in abundance and probability of persistence may be inadequate to prevent trades that increase fragmentation.  相似文献   
993.
Three-breed hybrids Cuban zebu x (Azerbaijan zebu x Aberdeen Angus) surpassed the Azerbaijan zebu and two-breed Azerbaijan zebu with Brown Latvian, Black Pied, and Aberdeen Angus breeds in weight, length, width, area, and thickness of hides. Minimum indices were obtained or purebred animals.  相似文献   
994.
A species of the genus Gonoclostera Butler, 1877, G.fangi sp.nov., from Yunnan, China is described in the present paper. Generic diagnosis and list of world species, as well as the photos of adults and genitalia of the new species are also provided.  相似文献   
995.
996.

Purpose  

Cadmium (Cd) is a toxic heavy metal, accumulated in soil by anthropogenic activities and has serious effects on soil microbial activities in contaminated soils. Moreover, there is a lack of reliable data on the effects of Cd in the soil-plant system, since most of the information on Cd-microorganism interactions in soils are based on sewage sludge without plants. The main objective of this study was to assess the effects of Cd on soil microbial activities and community structure during growth of plant.  相似文献   
997.
998.
999.
A progressive part of protected area management program in Lao PDR is a land and forest allocation program which contains critical elements that delegate right of land and forest use to local people. This study analyzes the gap between the original intent of the program and its actual implementation by local officials in Phou Xang He protected area, and discusses policy issues that need to be addressed. It appears that several types of non-compliance with regulations by local people have occurred, with local officials tacitly ignoring infractions. By switching viewpoints, however, it appears that the local officials permit these infractions as a way of allowing local people to secure their livelihoods. As constraints on the realities of land and forest use vary widely in and around villages in different locales, there is a need for government to allow local officials flexibility in implementing policies.  相似文献   
1000.
Amplified fragment length polymorphism (AFLP) analysis is a rapid and efficient method for producing DNA fingerprints and molecular characterization. Our objectives were to: estimate genetic similarities (GS), marker indices, and polymorphic information contents (PICs) for AFLP markers in almond cultivars; assess the genetic diversity of almond cultivars and wild species, using GS estimated from AFLP fingerprints and molecular characterization; and facilitate the use of markers in inter-specific introgression and cultivar improvement. The genetic diversity of 45 almond cultivars from Iran, Europe, and America, were studied assaying 19 primer combinations. In addition, several agronomic traits were evaluated, including flowering and maturity times, self-incompatibility, and kernel and fruit properties. Out of the 813 polymerase chain reaction fragments that were scored, 781 (96.23%) were polymorphic. GS ranged from 0.5 to 0.96, marker indices ranged from 51.37 to 78.79, and PICs ranged from 0.56 to 0.86. Results allowed the unique molecular identification of all assayed genotypes. However, the correlation between genetic similarity clustering as based on AFLP and clustering for agronomic traits was low. Cluster analysis based on AFLP data clearly differentiated the genotypes and wild species according to their origin and pedigree, whereas, cluster analysis based on agronomic data differentiated according the pomological characterization. Our results showed the great genetic diversity of the almond cultivars and their interest for almond breeding.  相似文献   
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