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411.
412.
Population viability analysis as a tool in wildlife conservation policy: With reference to Australia
David B. Lindenmayer Tim W. Clark Robert C. Lacy Virginia C. Thomas 《Environmental management》1993,17(6):745-758
Wildlife conservation policy for endangered species restoration follows a six-phase process. Population viability analysis
(PVA) can play a major contributing role in four of these. PVA, as discussed here, is a technique where extinction vulnerabilities
of small populations are estimated using computer simulation modeling. The benefits and limitations of using PVA in wildlife
decision and policy processes are reviewed based on our direct experience. PVA permits decision makers to set time frames
for management, estimate the required magnitude of restoration efforts, identify quantitative targets for species recovery,
and select, implement, monitor, and evaluate management strategies. PVA is of greatest value for rare species policy and management.
However, a limitation of PVA simulation models is that they are constrained by the amount of biological data available, and
such data are difficult to obtain from small populations that are at immediate risk of extinction. These problems may be overcome
with improved models and more data. Our experience shows benefits of PVA far outweigh its limitations, and applications of
the approach are most useful when integrated with decision analysis and completed within an adaptive management philosophy.
PVAs have been carried out for 14 Victorian species and less used elsewhere in Australia. Management and recovery plans are
developed from these PVAs. We recommend that PVA be used to guide research programs, develop conservation strategies, and
inform decision and policy making for both endangered and nonendangered species because it can significantly improve many
aspects of natural resource policy and management. 相似文献
413.
Tim Jones 《Natural resources forum》1993,17(3):170-180
Large-scale exploitation of fossil fuels and nuclear power can have an adverse effect on the human and natural environment. That need not be the case, if the effect on the environment is carefully assessed to ensure the development of a sustainable approach. This paper examines the process of environmental impact assessment (EIA) for coal from an international perspective. The concept of EIA is not new. A formalized process of EIA was introduced in the USA in 1970, and more recently similar legislation has been implemented in other countries. The member states of the European Community are required to adopt EIA regulations, as set out in Directive 85/337/EEC. Elsewhere, in Japan and Australia, there are requirements for EIA and a growing need for the process can be seen in developing countries. A comparison is made of the EIA process for coal in the international arena, and exemplary procedures are highlighted. Potential problems such as delays, modifications and additional costs are analysed, and the benefits of EIA, both to industry and environment, are discussed. A database of coal-related EIA would facilitate an exchange of information on the subject. 相似文献
414.
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416.
The field of fetal therapy has so far escaped from formal accreditation and quality control. Despite that, current published evidence shows that outcomes of interventions in younger fetal therapy centers are similar to what is achieved in more experienced centers and outcomes of interventions have improved over time. The question however remains what is not being published and what should be the standard of care, given the lack of level 1 evidence from randomized controlled trials for many interventions. Formal collaborative networks such as NAFTnet and others allow for anonymized benchmarking of center outcomes, without publicly shaming (and financially punishing) underperforming centers. Large registries also allow for tracking of rare complications and may result in improved patient outcomes over time. Core outcome sets, which could serve as a basis for outcome reporting, are available for some conditions, but certainly not for all, resulting in communication difficulties between centers. Formal accreditation, quality control, and outcome reporting are hard to implement, expensive, and may result in decreasing access to care by pushing smaller centers out of the market. Despite the existing difficulties, international societies have committed to quality improvement, and fetal therapy programs are strongly recommended to participate in voluntary outcome tracking. 相似文献
417.
Jan Deprest Marc Van Ranst Lore Lannoo Emma Bredaki Greg Ryan Anna David Jute Richter Tim Van Mieghem 《黑龙江环境通报》2020,40(13):1755-1758
Even though the global COVID-19 pandemic may affect how medical care is delivered in general, most countries try to maintain steady access for women to routine pregnancy care, including fetal anomaly screening. This means that, also during this pandemic, fetal anomalies will be detected, and that discussions regarding invasive genetic testing and possibly fetal therapy will need to take place. For patients, concerns about Severe Acute Respiratory Syndrome-Corona Virus 2 will add to the anxiety caused by the diagnosis of a serious fetal anomaly. Yet, also for fetal medicine teams the situation gets more complex as they must weigh up the risks and benefits to the fetus as well as the mother, while managing a changing evidence base and logistic challenges in their healthcare system. 相似文献
418.
Lara Gotha Vagisha Pruthi Nimrah Abbasi Abhaya V. Kulkarni Paige Church James M. Drake Jose C.A. Carvalho Yenge Diambomba Varsha Thakur Greg Ryan Tim Van Mieghem 《黑龙江环境通报》2020,40(12):1499-1507
Worldwide, about 150 000 infants are born with spina bifida yearly, making this condition one of the most common fetal central nervous system anomalies compatible with life. Over the last decade, major changes have been introduced in the prenatal diagnosis and management of spina bifida. In this review, we provide a brief summary of the current management of fetal spina bifida and present essential information that should be provided to expecting parents when their fetus has been diagnosed with spina bifida. This information is focused around common parental questions, as encountered in our typical clinical practice, to facilitate knowledge translation. 相似文献
419.
Tim Marshall 《Journal of Environmental Planning and Management》1998,41(4):421-443
The first round of regional planning strategies in England in the 1990s only made tentative attempts to incorporate environmental priorities. More recent work is giving sustainability a higher profile and other factors, including the establishment of more co-ordinated government regional offices in 1994 and of the Environment Agency (with new regional boundaries) in 1996, are also raising questions about the future focus on economic and environmental planning at the regional level. Regional planning in Germany has incorporated environmental considerations to a greater degree and for longer. The paper examines experience in Lower Saxony (Niedersachsen) in the 1990s, when the Land has been ruled first by a Social Democrat-Green Party coalition and then by the Social Democrats on their own, but with still some environmental emphasis. Particular attention is paid to policies in the energy, water and waste sectors. Although any direct transfer to experience in England is clearly not possible, it is argued that there are implications for possible directions for regional planning. This is the case whether the new British government initiates major changes or whether there is only gradual building on the foundations laid since 1990. 相似文献
420.
The cost of reproduction can generate covariation between demographic rates that can potentially influence demography and population dynamics in long-lived iteroparous species. However, there has been relatively little work linking the survival cost of reproduction and population dynamics. The apparent scarcity of information on this important link is potentially due to covariation between vital rates, which can substantially influence fluctuations in population size. In this paper we examine the opportunity for survival costs of reproduction to leave a dynamic signature using a simulation model based broadly on an ungulate life history. We find that an increase in the cost delays the onset of reproduction and reduces reproductive rates of young, but not of prime-age, females. Accordingly, the number of offspring produced declines and the interval between reproductive events increases among young females experiencing high cost. These effects are translated to an age structure skewed toward young ages and reduced population density. These results suggest that, by delaying reproduction when conditions deteriorate, females protect their survival during the critical first three years of life, after which the negative effect of reproduction on survival declines. Unless conditions for reproduction are severe, it is not profitable to delay reproduction beyond age 3 years due to the high risk of death before having a chance to reproduce. We also demonstrate that lack of adjustment of reproductive strategies to elevated levels of the cost of reproduction, for example due to rapid changes in environmental conditions, results in lower average density and longevity compared to females that have sufficient time to adjust to changes in the cost. This suggests that even moderate costs of reproduction may have a major negative effect on population dynamics of ungulates. 相似文献