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71.
The Great Barrier Reef Marine Park was established to provide for conservation and ecologically sustainable multiple use of 344,400 km2 of a large marine ecosystem. Management is based on multiple use, with zoning as a fundamental component of marine spatial planning. The legislative framework, including a specific Act and Regulations, address the objectives of ecosystem-based, integrated management of human uses and impacts consistent with best contemporary understanding of biological diversity. Zoning is one of a suite of management tools that include other spatial and temporal management tools and non-spatial measures including public education, community engagement, codes of environmental best practice, industry partnerships and economic instruments. The first section of the Great Barrier Reef Marine Park came into operation in 1981 and the most recent zoning came into operation in mid 2004. The paper discusses some common misunderstandings about zoning and identifies lessons that appear relevant for others addressing management and use of marine ecosystems and natural resources.  相似文献   
72.
In recent years, developments in ICP-MS have led to improved methods for determination of long-lived radionuclides. This paper reports the use of NH(4)OH as a matrix modifier and ETV sample introduction for the determination of technetium-99 ((99)Tc) in a variety of environmental and biological samples, using Re as carrier and (99m)Tc as yield monitor in the chemical separation method. Addition of an excess of NH(4)OH led to a stable (99)Tc signal, reduced memory effect, better reproducibility and reduced detection limits. Following radiochemical separation of (99)Tc from the sample matrix, detection limits in the order of a few microBq have been achieved. ETV has also proved applicable for rapid, direct analysis of a number of environmental samples having relatively high concentrations of (99)Tc (sediment extracts and river water close to nuclear installations). However, in this case, control of matrix effects (signal reduction and enhancement) using standard additions is necessary.  相似文献   
73.
There has been a recent explosion in the use of artificial intelligence (AI), which is now part of our everyday lives. Uptake in medicine has been more limited, although in several fields there have been encouraging results showing excellent performance when AI is used to assist in a well-defined medical task. Most of this work has been performed using retrospective data, and there have been few clinical trials published using prospective data. This review focuses on the potential uses of AI in the field of fetal cardiology. Ultrasound of the fetal heart is highly specific and sensitive in experienced hands, but despite this there is significant room for improvement in the rates of prenatal diagnosis of congenital heart disease in most countries. AI may be one way of improving this. Other potential applications in fetal cardiology include the provision of more accurate prognoses for individuals, and automatic quantification of various metrics including cardiac function. However, there are also ethical and governance concerns. These will need to be overcome before AI can be widely accepted in mainstream use. It is likely that a familiarity of the uses, and pitfalls, of AI will soon be mandatory for many healthcare professionals working in fetal cardiology.  相似文献   
74.
Abstract

A strategic approach to local sustainability assessment requires that sustainability implications of proposed policies, plans and programmes are evaluated. These evaluations need to critically consider organizational structures, processes and outcomes. The establishment of ‘communities of practice’, groups or networks of practitioners with shared interests, is a helpful mechanism for facilitating change in a wide range of organizations. This paper analyses the potential for communities of practice to contribute to the implementation of sustainability assessments by local government. Focusing on Sutherland Shire Council in Sydney, Australia, this paper presents the findings of a project that engaged practitioners in the design of a sustainability assessment system. The establishment of communities of practice helped to break down the ‘silos’ created by institutional divides within local government, but this approach also raises challenges in maintaining momentum and overcoming political agendas.  相似文献   
75.
The temporal and geographical distributions of planktonic bacteria, and their ability to degrade sodium dodecyl sulphate (SDS) (AS(+) phenotype), in a polluted South Wales river, is reported for five sites source to estuary sampled during a one-year period. The annual mean prevalence of AS(+) isolates at all sites was 8.1-16.0% of the total number of isolates, and these values were not altered by including SDS in culture media. Although the proportion of AS(+) isolates in clean water at the source was not significantly different to that of polluted sites, the AS(+) cell density was lower at the source because of its lower overall numbers. The percentage of AS(+) isolates in estuarine water was higher than at the three polluted mid-river sites, but when cell numbers were taken into account, the AS(+) cell density was the same at all polluted sites including the estuary. There was no correlation between percentage of AS(+) and either BOD or oxygen concentration, but AS(+) isolates were significantly more prevalent at the end of summer. Of the AS(+) isolates, more than half contained constitute alkysulphate enzymes, the remainder being induced or repressed by SDS; the relative proportions of enzyme regulatory type did not vary significant between sites or at different sampling times.  相似文献   
76.
Four populations of the predatory gastropodNucella lapillus were sampled at sites around the South West Peninsula of England in 1986, and analysed for allozyme variation at 18 enzyme loci. Two of these loci, Gpd-1 andHk-1, exhibited sex-specific phenotypes. An absolute locus association was observed between two other loci,Mdh-1 andEst-3. This association was only found at one site (Prawle), and it is suggested that the presence of chromosomal polymorphisms could explain this finding. As a measure of overall similarity, Nei's genetic identity statistic,I, was calculated; the mean for all populations was 0.989, with values ranging from 0.981 to 0.997. Although similar on this gross level, considerable interpopulation variation was evident. Observed mean heterozygosity (per locus) ranged from 0.043 to 0.104 (mean 0.074). Populations differed also in the loci at which significant heterozygote deficits were seen (of the seven deficits recorded only those at thePep-1 locus were consistent across sites) and in the presence of rare alleles undetected elsewhere. The variation observed showed no correlation to shell morphology or geographical distance and confirmed the conclusion that species of the genusNucella show considerable disjunct variation.  相似文献   
77.
ABSTRACT: Biophysical and socioeconomic effects are identified in reservoir, downstream, division channel, and receiving water body areas. Overall, the projects have been socially useful, especially from the perspective of hydroelectric, log driving, and economic development benefits. However selected socially inequitable aspects of the projects and other problems related to erosion, turbidity, multiple resource use, failure to clear trees, and heritage resource losses are identified. Suggestions for planning similar projects are presented.  相似文献   
78.
This assessment of the environmental protection regulatory system for the $2.2 billion iron and steel plant, oil refinery, and thermal generating station composing the core of the greenfield Nanticoke industrial complex is based upon: the use of governmental and industrial research in project management; technology and institutional arrangements for environmental protection; evidence of environmental changes to date; analysis of government and industrial approval files; and interviews with government, industry, and interest group representatives. Planning, regulation, and management have been reasonably efficient and effective to the beginning of the operational stage for all three major industries as of spring 1980. Of major future concern, however, is management of the cumulative and synergistic impacts of the industries and associated development on air quality as well as the lands, waters, and sensitive ecosystems of the nearby Lake Erie coast. Continuous monitoring, more comprehensive research, and better overall coordination of government, industrial, and public interests are required if Nanticoke benefits are to be achieved without undue cost to pre-project resource users within and outside the Haldimand-Norfolk region.  相似文献   
79.
This paper examines causes and consequences of wetland losses in coastal Louisiana. Land loss is a cumulative impact, the result of many impacts both natural and artificial. Natural losses are caused by subsidence, decay of abandoned river deltas, waves, and storms. Artificial losses result from flood-control practices, impoundments, and dredging and subsequent erosion of artificial channels. Wetland loss also results from spoil disposal upon wetlands and land reclamation projects.Total land loss in Louisiana's coastal zone is at least 4,300 ha/year. Some wetlands are converted to spoil banks and other eco-systems so that wetland losses are probably two to three times higher. Annual wetland losses in the Barataria Bay basin are 2.6% of the wetland area. Human activities are the principal determinants of land loss. The present total wetland area directly lost because of canals may be close to 10% if spoil area is included. The interrelationship between hydrology, land, vegetation, substrate, subsidence, and sediment supply are complicated; however, hydrologic units with high canal density are generally associated with higher rates of land loss and the rate may be accelerating.Some cumulative impacts of land loss are increased saltwater intrusion, loss of capacity to buffer the impact of storms, and large additions of nutrients. One measure of the impact is that roughly $8–17 × 106 (U.S.A.) of fisheries products and services are lost annually in Louisiana.Viewed at the level of the hydrologic unit, land loss transcends differences in local vegetation, substrate, geology, and hydrology. Land management should therefore focus at that level of organization. Proper guideline recommendations require an appreciation of the long-term interrelations of the wetland estuarine system.  相似文献   
80.
The EPA Storm Water Management Model was used to model the effects of urban and agricultural development on storm water runoff from uplands bordering a Louisiana swamp forest. Using this model, we examined the effects of changing land use patterns. By 1995 it is projected that urban land on the uplands bordering the swamp will increase by 321 percent, primarily at the expense of land currently in agriculture. Simulation results indicate that urbanization will cause storm water runoff rates to be up to 4.2 times greater in 1995 than in 1975. Nutrient runoff will increase 28 percent for nitrogen (N) and 16 percent for phosphorus (P) during the same period. The environmental effects of these changes in the receiving swamp forest are examined.  相似文献   
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