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111.
The Resource Management Act, passed in 1991, has significantly revised the practice of Environmental Impact Assessment (EIA) in New Zealand. In contrast to a previous emphasis on environmental impact reports of major projects, the new requirements call for environmental impact assessment of all resource consent applications and of all regional, district and city policies and plans. This signals a change directed at incorporating environmental considerations into day‐to‐day planning decisions, with the purpose of achieving sustainable management. The paper identifies and discusses some key issues which are critical for successful integration of EIA within a planning framework.  相似文献   
112.
Preface     
Mitigation and Adaptation Strategies for Global Change -  相似文献   
113.
A case of a prenatally recognized hepatic mesenchymal hamartoma is presented and the literature reviewed. These tumors are benign and usually present in early infancy with symptoms that are related to the mass effect on adjacent organs. Radiologic methods used in the past to image this tumor include angiography and ultrasound. However, there is no specific radiologic finding, and, therefore, the diagnosis is usually made during surgery. Once the tumor is removed, the prognosis is generally good. With the increasing use of high resolution ultrasound in prenatal diagnosis, this rare tumor should be considered in the differential diagnosis of any multicystic mass found in the fetal abdomen. The recognition of a mass should then alert the physician to the need for early neonatal intervention.  相似文献   
114.
We examined the inheritance of theMytilus edulis CaM-1 Intron 3 locus, a non-coding DNA locus with two potentially neutral length-variants. The polymerase chain reaction (PCR) was used to determine theCaM-1 genotype for 799 larvae obtained from 11 laboratory crosses. Larvae were typed singly only 8 to 24 h after fertilization. We find evidence that each allele can be inherited from either sex, that there are no barriers to fertilization between gametes of different genotypes, and that most larvae have genotypes compatible with Mendelian inheritance of the locus. Deviations from expected genotype frequencies were found in some crosses; we suggest that a contributing factor is aneuploidy in early larvae, but a major cause is more likely to be selection at a locus linked toCaM-1, occurring under the artificial laboratory culture conditions. This study demonstrates the feasibility of applying molecular genetic techniques to early larval stages of marine bivalves, and presents a new non-destructive biopsy method for DNA analysis from living adult mussels.  相似文献   
115.
PCR (polymerase chain reaction) amplification of non-coding introns in phylogenetically widespread genes, using DNA primers based on the conserved exon sequences, provides a widely applicable strategy for finding DNA polymorphisms in eukaryotic genomes. Polymorphisms in introns provide a new source of potentially neurtral genetic markers for use in population biology. Here we use this approach to design PCR primers for an intron of calmodulin genes. We show that there are at least two calmodulin genes in mussels of theMytilus edulis species complex, and using gene- and species-specific primers we resolve two alleles at a calmodulin intron locus. Population surveys using PcR of adult mussel DNA reveal that genotype frequencies at most sites surveyed in England, Scotland and Italy, conform to Hardy-Weinberg equilibrium, suggesting that this is a novel neutral genetic marker. The data also provide preliminary evidence for restricted gene flow between mussel populations on the west and northeast coasts of Britain, and for local effects around the Thames estuary.  相似文献   
116.
We studied the effects of grazing by two species of sea urchins on two species of kelp (Macrocystis pyrifera and Pterygophora californica) in the San Onofre kelp bed in southern California from 1978 through 1981. Both red sea urchins, Strongylocentrotus franciscanus, and white sea urchins, Lytechinus anamesus, were abundant and lived in aggregations. The purple sea urchin (S. purpuratus) was rare at the study site and was not studied. The aggregations of red urchins were either relatively small and stationary (for over 3 yr) or relatively large and motile (advancing at about 2 m mo–1). Both stationary and moving aggregations were observed at the same time, and within 100 m of one another. Stationary aggregations of red urchins probably subsisted mainly on drift kelp and had no effect on kelp recruitment or on adult kelp abundance. In contrast, red sea urchins in large, motile aggregations or fronts ate almost all the macroalgae in their path. The condition of their gonalds indicated that red urchins in fronts were starved relative to red urchins in the small, stationary aggregations. Large, motile aggregations developed after 2 yr of declining kelp abundance (probably due largely to storms). We propose that a scarcity of drift algae for food results in a change in the behavior pattern of the red urchins and thus leads to the formation of large, motile aggregations. The aggregations of white urchins, which occurred along the offshore margin of the kelp bed, were large, but relatively stationary. The white urchins rarely ate adult kelps, but grazed extensively on early developmental stages of kelps and evidently prevented seaward expansion of the bed. The spatial distribution of both types of red urchin aggregations appeared to be unrelated to predation pressure from fishes or lobsters.Please address all requests for reprints to the senior author at his present address.  相似文献   
117.
Stratospheric ozone depletion threatens human health and the global environment. In 1987, the Montreal Protocol on Substances That Deplete the Ozone Layer (Montreal Protocol) set aggressive timelines for countries to phase-out products and organic chemicals that were causing rapid ozone depletion in the Antarctic stratosphere. The Global Environment Facility (GEF), established in 1991, is the largest multilateral funder of environmental protection projects and provides financial support for implementation of the Montreal Protocol. This paper summarizes GEF investments to address ozone-depleting substances (ODS) in Countries with Economies in Transition (CEITs), presents case studies from representative countries, and discusses lessons learned. Complementing the work of the Multilateral Fund that supports developing country Parties of the Montreal Protocol, the GEF provides financial support to CEIT’s to address ODS phase-out targets and timelines. These investments include technology development and transfer, outreach and training, institution building, and programs to phase-out ODS. Working with partners in the public and private sectors, the GEF has allocated approximately US210 million, leveraging another US210 million, leveraging another US250 million in co-financing, for 28 ODS phase-out projects in 18 CEITs. GEF ODS project investments in CEITs have contributed to Protocol success by phasing-out 20,000 ozone depletion potential (ODP) Megagrams (Mg) of consumption and 29,000 ODP Mg of production. Among the GEF’s most significant efforts to eliminate ODS are projects that transfer technologies and strengthen institutional capabilities of partner countries. These projects have enabled the installation of non-ODS technologies, adoption of best practices by the private sector, and provided CEITs with the legislative and policy framework necessary to sustain ODS phase-out. Almost 25 years after its establishment, the Montreal Protocol with support from financial mechanisms such as the GEF, is a successful model for addressing global environmental challenges.  相似文献   
118.
119.
Francis J  Nilsson A  Waruinge D 《Ambio》2002,31(7-8):503-511
This article reviews the governance and management of Marine Protected Areas (MPAs), and the coral reefs they contain, in the eastern African Region. This includes the Comoros, Kenya, Madagascar, Mauritius, Mozambique, Tanzania, and the Seychelles. Three generations or categories of MPAs are distinguished: i) small areas for protection of a single species or unique marine habitat; iii) large multiple use MPAs designed for coastal development as well as biodiversity protection; and iii) MPAs managed by a nongovernmental organization (NGO) or the private sector. Each of these MPA types is examined according to the policies, legislation, and management systems they entail as well as the economic and community situation they operate within. The paper also provides a review of some eastern African MPAs in terms of their size and location, the type of MPA, zonation schemes, and financial status. The successes of the different types of MPAs are discussed based on specific indicators, such as changes in biodiversity, infrastructure, compliance to regulations and the level of involvement of primary stakeholders in the management. From the review it is clear that a fourth generation of MPAs may be forthcoming; community-based MPAs. Although lack of data makes it difficult to assess the effectiveness of these different categories of MPAs, it is clear that no MPA can succeed without support of the local communities. Generally, the results of the analysis are promising for MPAs, however a lack of data is hampering a deeper analysis. The major issues facing MPAs in the region are highlighted, as well as some regional initiatives striving to address these issues. A number of recommendations are made, aiming to strengthen the establishment and management of MPAs in the eastern African region.  相似文献   
120.
Editorial     
Mitigation and Adaptation Strategies for Global Change -  相似文献   
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