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排序方式: 共有32条查询结果,搜索用时 31 毫秒
1.
In the Wasatch Range Metropolitan Area of Northern Utah, water management decision makers confront multiple forms of uncertainty and risk. Adapting to these uncertainties and risks is critical for maintaining the long‐term sustainability of the region's water supply. This study draws on interview data to assess the major challenges climatic and social changes pose to Utah's water future, as well as potential solutions. The study identifies the water management adaptation decision‐making space shaped by the interacting institutional, social, economic, political, and biophysical processes that enable and constrain sustainable water management. The study finds water managers and other water actors see challenges related to reallocating water, including equitable water transfers and stakeholder cooperation, addressing population growth, and locating additional water supplies, as more problematic than the challenges posed by climate change. Furthermore, there is significant disagreement between water actors over how to best adapt to both climatic and social changes. This study concludes with a discussion of the path dependencies that present challenges to adaptive water management decision making, as well as opportunities for the pursuit of a new water management paradigm based on soft‐path solutions. Such knowledge is useful for understanding the institutional and social adaptations needed for water management to successfully address future uncertainties and risks.  相似文献   
2.
Factors Affecting Population Assessments of Desert Tortoises   总被引:1,自引:0,他引:1  
Abstract: Desert tortoises have been a subject of controversy since their listing as threatened in 1990. With a wide geographic range and more living individuals than any other listed land animal, biologists have needed to detect population trends against a "noisy" background of strong annual changes. We obtained annual population estimates of desert tortoises over 6 consecutive years at a 2.59-km2 plot in Joshua Tree National Park, California. Our estimates, based on weekly spring surveys, varied substantially, particularly between wet and dry years. Concurrently, we followed 10 radiotagged animals for 3 years to corroborate the surveys. Population density was determined separately for each year and for all years combined. Our best population estimate was an average of 67 adult tortoises, three times more than the density reported in a 1978 survey of the same site. Annual mortality was low ( <10%), and the animals showed extreme site fidelity. Apparent changes in population size were most strongly related to the animals' varying susceptibility to capture. In dry years, home ranges decreased, captures decreased, and effort required to find each tortoise nearly doubled. Our data confirm that tortoises are likely to be undercounted during dry years and call into question earlier studies conducted during droughts.  相似文献   
3.
In practice, complete demand systems are not estimated. Rather, either an incomplete demand system is estimated, or separability is invoked and a partial demand system is estimated. This paper considers the relationship between the conventional compensating variation (equivalent variation) and the corresponding welfare measure that can be derived from a partial demand system and the current budget allocation to the separable group. Even assuming the separability assumption invoked is appropriate, these partial measures provide, in general, only a limited amount of information about the compensating variation and no information about the equivalent variation. Great care is therefore needed when using partial welfare measures to evaluate policy.  相似文献   
4.
We briefly outline the information-theoretic (I-T) approaches to valid inference including a review of some simple methods for making formal inference from all the hypotheses in the model set (multimodel inference). The I-T approaches can replace the usual t tests and ANOVA tables that are so inferentially limited, but still commonly used. The I-T methods are easy to compute and understand and provide formal measures of the strength of evidence for both the null and alternative hypotheses, given the data. We give an example to highlight the importance of deriving alternative hypotheses and representing these as probability models. Fifteen technical issues are addressed to clarify various points that have appeared incorrectly in the recent literature. We offer several remarks regarding the future of empirical science and data analysis under an I-T framework.  相似文献   
5.
While collating contributions and comments from 36 researchers, the coordinating authors accidentally omitted Dr. Suzanne Carrière from the list of contributing co-authors. Dr. Carrière’s data are described in Tables 1 and 3, Figure 2 and several places in the narrative. The new author list is thus updated in this article.  相似文献   
6.
For humanitarian organisations, accurate data are essential to identify emerging health problems and determine programme needs. We visited 45 post-emergency phase displaced persons camps and collected three months' mortality data which we compared with organisations' routine mortality reports. Organisations reported 612 deaths and we identified 741 deaths, for a mortality-reporting ratio, defined as the number of organisation-reported deaths divided by the number of investigator-identified deaths, of 83 per cent. For the majority of camps which under-reported deaths, mortality reporting ratios were significantly higher for women than men, and for camps with central mortality registers rather than those without. In the few camps which over-reported deaths, these occurred primarily among children younger than five years of age, probably due to the inclusion of abortions and stillbirths. Despite the overall under-reporting of deaths by humanitarian organisations, the existing health information systems appear to estimate mortality rates adequately in these post-emergency camps. However, organisations should improve the precision and completeness with which they report the characteristics of deaths in order to provide valuable data to target their programmes at the most vulnerable people.  相似文献   
7.
In an emergency, the international community responds to the immediate health needs of refugees through the establishment of action-oriented, life-saving services. Healthcare delivery is often managed with limited, if any, coordination with local health management structures. In situations where refugees remain in the host country for many years, sustainability issues inevitably arise. Refugee-hosting governments may ultimately be called upon to assume the management and funding of refugee services. Planning for service integration, while protecting against declines in service quality, is a challenge in the typically resource-poor host environments. This paper discusses these issues by presenting the experience of the West Nile districts in northern Uganda, and describes quality design as a relevant planning methodology. Quality design is a systematic planning approach that documents and directly incorporates the service users' self-defined expectations and needs.  相似文献   
8.
Abdallah S  Heinzen R  Burnham G 《Disasters》2007,31(4):417-434
On 7 August 1998 truck bombs destroyed the US Embassies in Kenya and Tanzania.(1) The response in both countries was characterised by an absence of incident command, limited pre-hospital care, a disorganised hospital response and a lack of transportation for those injured. In the next five years USD 50 million was provided by the United States Agency for International Development (USAID) to alleviate the resulting suffering, support reconstruction and strengthen disaster preparedness capacity in the two countries. These two programmes have enhanced awareness of disaster management issues, improved training capacity, built response structures and provided material resources. Their design and implementation provide lessons for future disasters in developing countries. The assistance programmes evolved very differently. In Kenya the programme largely excluded the public sector and the potential for government coordination, while the Tanzanian programme concentrated heavily on central government and regional hospital structures-largely omitting the non-governmental or civil society sector. Excluding key stakeholders raises concerns about programme sustainability and the ability to respond effectively to future emergencies.  相似文献   
9.
The work reported indicates that there could be a potential of ground water pollution by NO3-N from turkey facilities built on both sandy and clay soils. At four different depths (30.54, 61.08, 91.62, and 122.16 cm), the NO3-N levels for the clay soil were 1572, 497, 66, and 28 ppm, and those for the sandy soil were 293, 425, 324, and 164 ppm, respectively. No significant P increases were observed but there did exist a significant increase of K in the topsoil for both clay and sandy turkey structures. The results show that swine hoop houses with less than three or four years of age may not pose a threat to groundwater pollution due to the leaching of nutrients. The only dairy feedlot sampled in this study, although it has been used for more than 20 years, did not show leaching of NO3-N and P. However, it did show a significantly elevated concentration of potassium in the topsoil, as compared to the background sample. More sites should be investigated to verify this.  相似文献   
10.
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