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111.
Economic growth,biodiversity loss and conservation effort   总被引:6,自引:0,他引:6  
This paper investigates the relationship between economic growth, biodiversity loss and efforts to conserve biodiversity using a combination of panel and cross section data. If economic growth is a cause of biodiversity loss through habitat transformation and other means, then we would expect an inverse relationship. But if higher levels of income are associated with increasing real demand for biodiversity conservation, then investment to protect remaining diversity should grow and the rate of biodiversity loss should slow with growth. Initially, economic growth and biodiversity loss are examined within the framework of the environmental Kuznets hypothesis. Biodiversity is represented by predicted species richness, generated for tropical terrestrial biodiversity using a species-area relationship. The environmental Kuznets hypothesis is investigated with reference to comparison of fixed and random effects models to allow the relationship to vary for each country. It is concluded that an environmental Kuznets curve between income and rates of loss of habitat and species does not exist in this case. The role of conservation effort in addressing environmental problems is examined through state protection of land and the regulation of trade in endangered species, two important means of biodiversity conservation. This analysis shows that the extent of government environmental policy increases with economic development. We argue that, although the data are problematic, the implications of these models is that conservation effort can only ever result in a partial deceleration of biodiversity decline partly because protected areas serve multiple functions and are not necessarily designated to protect biodiversity. Nevertheless institutional and policy response components of the income biodiversity relationship are important but are not well captured through cross-country regression analysis.  相似文献   
112.
This paper addresses the compatibility of World Bank policies towards population growth, development and biodiversity in the Third World. The World Bank has been central to the design and implementation of the Global Environment Facility (GEF), the remit of which includes the conservation of global biodiversity. However, the Bank's influence over the facility has in itself created controversy which may undermine its effectiveness. More significantly, the Bank's commitment to the GEF is subverted by its policies in other social and economic sectors. The World Bank, together with the International Monetary Fund (IMF), directs the structural adjustment of Third World economies through economic deregulation and privatization. This approach exacerbates inequalities and further empowers large landowners who may then displace tenant farmers and claim exclusive rights to former common land. Thus, biodiversity loss occurs as large landowners reorientate the land use towards the production of export goods and dispossessed farmers invade marginal land. Population growth influences biodiversity loss through its contribution to agricultural intensification and the settlement of marginal land. The World Bank encourages this trend through its non-committal approach to population control, but more especially through structural adjustment's positive effect on fertility.  相似文献   
113.
ABSTRACT: A streamflow duration curve illustrates the relationship between the frequency and magnitude of streamflow. Flow duration curves have a long history in the field of water-resource engineering and have been used to solve problems in water-quality management, hydropower, instream flow methodologies, water-use planning, flood control, and river and reservoir sedimentation, and for scientific comparisons of streamflow characteristics across watersheds. This paper reviews traditional applications and provides extensions to some new applications, including water allocation, wasteload allocation, river and wetland inundation mapping, and the economic selection of a water-resource project.  相似文献   
114.
Summary In this paper the formal environmental education being delivered in three countries in the South Pacific Region, Fiji (Melanesia), Kiribati (Micronesia) and Niue (Polynesia) is evaluated. The findings reveal that environmental education is at different stages of evolution in each of these countries. At present only Niue appears to deliver environmental education effectively when compared with models of good practice suggested in the literature. Some general recommendations are included for the improvement of environmental education in Fiji and Kiribati.Neil Taylor was until recently a Fellow in Science Education at the University of the South Pacific, PO Box 1168, Suva, Fiji. He is now a senior research student at the Centre for Mathematics and Science Education at Queensland University of Technology. Dr Teny Topalian has until very recently been the co-ordinator of the Public Marine Education Programme run as part of the Marine Studies Programme of the University of the South Pacific. She has now returned to her position as Assistant Professor in Natural Sciences and Biology at California State University, Long Beach, California, USA.  相似文献   
115.
This paper is the report of a meetingthat gathered many of the UK's most senioranimal scientists with representatives of thefarming industry, consumer groups, animalwelfare groups, and environmentalists. Therewas strong consensus that the current economicstructure of agriculture cannot adequatelyaddress major issues of concern to society:farm incomes, food security and safety, theneeds of developing countries, animal welfare,and the environment. This economic structure isbased primarily on competition betweenproducers and between retailers, driving foodprices down, combined with externalization ofmany costs. These issues must be addressed by acombination of legislation, restructuring ofthe market, and use of public funds. Themeeting included workshops that made otherrecommendations for research and education. Themost urgent requirement is recognition thatchange is needed and development of a visionfor what that change must achieve.  相似文献   
116.
The environmental, socioeconomic and cultural significance of glaciers has motivated several countries to regulate activities on glaciers and glacierized surroundings. However, laws written to specifically protect mountain glaciers have only recently been considered within national political agendas. Glacier Protection Laws (GPLs) originate in countries where mining has damaged glaciers and have been adopted with the aim of protecting the cryosphere from harmful activities. Here, we analyze GPLs in Argentina (approved) and Chile (under discussion) to identify potential environmental conflicts arising from law restrictions and omissions. We conclude that GPLs overlook the dynamics of glaciers and could prevent or delay actions needed to mitigate glacial hazards (e.g. artificial drainage of glacial lakes) thus placing populations at risk. Furthermore, GPL restrictions could hinder strategies (e.g. use of glacial lakes as reservoirs) to mitigate adverse impacts of climate change. Arguably, more flexible GPLs are needed to protect us from the changing cryosphere.  相似文献   
117.
The growing complexity and global nature of wildlife poaching threaten the survival of many species worldwide and are outpacing conservation efforts. Here, we reviewed proximal and distal factors, both social and ecological, driving illegal killing or poaching of large carnivores at sites where it can potentially occur. Through this review, we developed a conceptual social–ecological system framework that ties together many of the factors influencing large carnivore poaching. Unlike most conservation action models, an important attribute of our framework is the integration of multiple factors related to both human motivations and animal vulnerability into feedbacks. We apply our framework to two case studies, tigers in Laos and wolverines in northern Sweden, to demonstrate its utility in disentangling some of the complex features of carnivore poaching that may have hindered effective responses to the current poaching crisis. Our framework offers a common platform to help guide future research on wildlife poaching feedbacks, which has hitherto been lacking, in order to effectively inform policy making and enforcement.  相似文献   
118.
The Arctic marine ecosystem is shaped by the seasonality of the solar cycle, spanning from 24-h light at the sea surface in summer to 24-h darkness in winter. The amount of light available for under-ice ecosystems is the result of different physical and biological processes that affect its path through atmosphere, snow, sea ice and water. In this article, we review the present state of knowledge of the abiotic (clouds, sea ice, snow, suspended matter) and biotic (sea ice algae and phytoplankton) controls on the underwater light field. We focus on how the available light affects the seasonal cycle of primary production (sympagic and pelagic) and discuss the sensitivity of ecosystems to changes in the light field based on model simulations. Lastly, we discuss predicted future changes in under-ice light as a consequence of climate change and their potential ecological implications, with the aim of providing a guide for future research.  相似文献   
119.
In recent years, the level of heavy metal pollution in urban areas has been of considerable concern. The principal source has been attributed to the motor vehicle and increasing inner city congestion, which has lead to a change and enlargement of transport stop-start zones. These areas of high traffic density are associated with an increased release of heavy metals into the adjacent residential or commercial areas. Seventy-five roadside dust samples were collected throughout the inner city and by-pass motorway areas of Thessaloniki, Northern Greece. Samples were taken from arterial, major and minor roads, as well as the ring road, to compare and contrast the levels of heavy metals, namely Cu, Zn, Cd, Mn and Pb. Flame Atomic Absorption Spectroscopy (FAAS) was developed to quantitatively determine concentrations of both total element and geochemical fractionation, within the two dust particulate fraction sizes <75 microm and 75-125 microm. Acid digestion using Aqua Regia (3:1 conc. HCl:HNO(3)) was employed for the total elemental analysis, a method that was validated through the use of certified reference materials (CRM). Fractionation studies involved a three-step sequential extraction method performed on five selected samples (representatives of high, mid and low total elemental concentrations). The resultant solutions were analysed for lead and zinc levels to ascertain fractionation throughout the different geochemical fractions, thus assessing bioavailability.It was found that congestion/stop-start traffic patterns did influence and have led to increased levels of heavy metal deposition along inner city roads compared to levels observed on the new relief ring road. Dust particulate fraction sizes were only found to show statistically significant differences in cadmium and manganese, at the probability P < 0.001 or 99.9% confidence limit. Both Cd and Mn showed higher total levels in the smaller fraction sizes (<75 microm), implying that their major release source is exhaust emissions. There were no significant differences in the other elements, at the P > 0.05 or 95% confidence limit. Road type was seen to have little affect on cadmium and manganese, though lead, copper and zinc were all found to show higher levels on the inner city routes. This can be related back to the wear-and-tear of vehicle components as a result of the stop-start traffic patterns (brake pads etc). Both Pb and Zn have shown to be in chemical forms that are bio available to ecosystems.  相似文献   
120.
OBJECTIVE: The initial months of licensure are especially hazardous for teenagers. Factors leading to crashes of novice 16-year-old drivers were identified. METHOD: Sixteen year-olds in Connecticut who were involved in nonfatal crashes during the first 8 months of licensure were interviewed, and police crash reports were examined. Crash types and contributing factors were identified. RESULTS: Three-fourths of the crash-involved teenagers were at fault. Their crashes resulted primarily when they ran off the road, rear ended another vehicle, or collided with another vehicle that had the right-of-way. Three factors contributed about equally to their crashes: failing to detect another vehicle or traffic control, speeding, and losing control of the vehicle or sliding. Slippery roads also were an important factor. Most failures to detect another vehicle or traffic control involved not looking thoroughly, distraction, or inattention. DISCUSSION: Based on the findings, potential countermeasures for reducing crashes of novice teenage drivers include adequate practice driving, in-vehicle monitoring devices, and electronic stability control. IMPACT ON INDUSTRY: More than half of the nonfatal, at-fault crashes of newly licensed 16-year-old drivers involved more than one contributing factor including speed, loss of control, and slippery roads. Efforts to reduce teenage crashes should focus on these factors.  相似文献   
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