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Record breaking heat waves have been recorded in Adelaide, Australia in recent years and climate change would likely increase the frequency, duration and severity of heat waves. This paper describes the governance and institutional arrangements during the development of an adaptation strategy (herein referred to as heat-health policy) for heat waves in Adelaide, Australia. In-depth, semi-structured interviews were conducted between June and August 2011 among 18 stakeholders who were involved in the participatory process during the development of the heat-health policy. Informed consent was obtained and interviews were recorded, transcribed verbatim and the data analysed using framework analysis. Interview data were supplemented by data gathered through a review of documents associated with the process. The results found that the process of developing the heat-health policy was initiated by the state government and comprised of stakeholders from both the state and non-state sectors. There was a high level of leadership and political commitment demonstrated during the process, given that the different players wanted a policy to be in place before any future heat wave. A Steering Committee was established that provided coordination and oversight in addition to the Emergency Management Act within the state which provided the legislative framework during the heat-health policy development process. Although the decision-making authority was controlled by a controlled by a public institution, to a larger extent, there was collaborative decision-making by virtue of the context in which the heat-health policy was developed. An assurance mechanism established during the process was among the factors that ensured accountability during the participatory process. Overall, the development of the heat-health policy in Adelaide was largely successful, attributed to the extent of political commitment from the state government and the sound institutional and legislative framework that facilitated the process. Good governance and institutional arrangements provide the enabling environment, the structures, systems and resources that would facilitate the development of adaptation strategies such as heat-health policies.  相似文献   
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Summary Previously we reported that inter-litter competition reduces the survival of pups born to pairs of female rats living and breeding in the same nesting environment. Inter-litter competition occurred when females gave birth asynchronously; specifically, when a female gave birth in the presence of 15 to 28-day-old pups, her newborn pups were likely to die as a result of nest intrusion by the older pups. In contrast, inter-litter competition occurred rarely when the two females gave birth synchronously. Because theories of facultative sex ratio adjustment predict that mothers giving birth in unfavorable circumstances should bias their offspring towards the more viable or less expensive sex, we predicted that litters born asynchronously would be female biased. Conversely, we also predicted that females giving birth under favorable conditions, i.e., synchronously, would bias their litters toward males. We found a female bias in asynchronous litters, but did not find a male bias in synchronous litters. Moreover, in contrast to other reports in the literature, the female bias in asynchronous litters was achieved without a reduction in litter size. Based on correlational data, we suggest several mechanisms that could produce this female bias: conditions at fertilization and implantation, time since the male last mated and number of pups suckling concurrently during gestation. Correspondence to: M.K. McClintock  相似文献   
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The ecological constraints model predicts that daily travel distance and home range size of social animals will increase as group size increases in order to meet the dietary needs of additional group members. This theory has been supported more predominantly by studies of frugivorous primate species than by studies of folivorous species. We examined the ranging patterns of mountain gorillas in Bwindi Impenetrable National Park, Uganda, who include both herbaceous vegetation and fruit in their diet, to determine how ecological, behavioral, and social parameters influence movement patterns. Data were collected from three groups of gorillas with overlapping home ranges at a low-altitude location (1,450–1,800 m) and one group at a high-altitude location (2,100–2,500 m) in Bwindi from September 2001 to August 2002. We analyzed daily travel distance and home range size in relation to group size, while also considering patterns of frugivory, rainfall, and location (proxy for food availability) within the park. Both daily travel distance and home range size were positively related to group size. In addition, the degree of frugivory positively influenced daily travel distance and home range size, while rainfall negatively influenced daily travel distance only. Finally, groups at the low-altitude location, with higher fruit availability, traveled less than the group at the high-altitude location. These results demonstrate that mountain gorillas in Bwindi provide support for the ecological constraints model, but further studies are needed to determine how fine-scale spatial and temporal availability of food resources influence movement patterns. Ranging patterns of Bwindi gorillas are compared to those observed in other gorilla populations in the context of the ecological constraints model.Communicated by D. Watts  相似文献   
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ABSTRACT: The New Castle County Resource Protection Area Technical Advisory Committee (RPATAC) requested that the University of Delaware utilize impervious cover estimates to evaluate the performance of the Water Resource Protection Area (WRPA) ordinance. This 1991 ordinance was the first in Delaware to protect the quantity and quality of drinking water supplies by limiting new development in WRPAs ‐ such as areas of ground water recharge, wellhead protection, drainage above reservoirs (reservoir watersheds), and limestone aquifers ‐ to a maximum 20 percent impervious cover. The research used geographic information system (GIS) techniques to evaluate the effectiveness of the ordinance in attaining its objective. The analysis indicated that 138 new developments were proposed in WRPAs since the ordinance was approved in 1991. The composite impervious cover of the 231 square kilometers of WRPAs in New Castle County is 15 percent, less than the 20 percent code requirement, ranging from 7 percent in recharge areas to 41 percent in several wellhead protection areas. To further protect drinking water supplies, the study results indicate, New Castle County should discourage code variances for applications in the more developed WRPAs, those where impervious cover already exceeds 20 percent, and should acquire parks and open space to protect the healthier WRPAs where impervious cover is currently less than 20 percent.  相似文献   
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Perchlorate has been identified as a water contaminant in 14 states, including California, Nevada, New Mexico, Arizona, Utah, and Texas, and current estimates suggest that the compound may affect the drinking water of as many as 15 million people. Biological treatment represents the most‐favorable technology for the effective and economical removal of perchlorate from water. Biological fluidized bed reactors (FBRs) have been tested successfully at the pilot scale for perchlorate treatment at several sites, and two full‐scale FBR systems are currently treating perchlorate‐contaminated groundwater in California and Texas. A third full‐scale treatment system is scheduled for start‐up in early 2002. The in‐situ treatment of perchlorate through addition of specific electron donors to groundwater also appears to hold promise as a bioremediation technology. Recent studies suggest that perchlorate‐reducing bacteria are widely occurring in nature, including in groundwater aquifers, and that these organisms can be stimulated to degrade perchlorate to below the current analytical reporting limit (< 4 μg/l) in many instances. In this article, in‐situ and ex‐situ options for biological treatment of perchlorate‐contaminated groundwater are discussed and results from laboratory and field experiments are presented. © 2002 Wiley Periodicals, Inc.  相似文献   
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The high frequency of speciation events associated with species flocks (i.e., radiations of closely related species) provides invaluable insight into the speciation process. Investigations of the speciation process in the marine environment are rare, and therefore, the genetic analysis of the rockfish genus Sebastes, considered an ancient marine species flock, provides an opportunity to investigate this process in the sea. Using both mitochondrial and nuclear markers, we analyzed five closely related species within the rockfish subgenus Sebastosomus. Our goal was to understand the evolutionary history and genetic relationships among species within this group and to provide evidence of recent speciation events within the subgenus. In the genetic analysis of the subgenus, we found different stages of the speciation process, with greater genetic divergences among three of the five species, evidence of recent divergence between two of the five species, Sebastes entomelas and S. mystinus, and significant genetic divergence between two lineages within S. mystinus revealing a signature of incipient speciation. We also found frequency differences of the two S. mystinus lineages among sample locations and found no evidence of introgression between the lineages at the location where both coexist. Although Sebastes is an example of an ancient species flock, this study provides evidence of ongoing speciation within the genus and reveals stages of this process from incipient to distinct species.  相似文献   
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