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661.
Ageing and urbanisation pose significant challenges for public health and urban planning. Ageing populations are at particular risk from hazards arising from urbanisation processes, some of which are in turn exacerbated by climate change. One approach for mitigating the negative effects of urbanisation on ageing populations is the leveraging of the beneficial effects of urban green infrastructure as a public health intervention in the planning process. We assessed the potential of available theoretical frameworks to provide the context for such leverage. This involved active engagement with academics and practitioners specialising in ageing, green infrastructure and health and well-being through a knowledge-brokering approach. We concluded that an integrated and comprehensive framework on the socio-cultural-ecological determinants of health is lacking. To address this, we present a set of principles for overcoming challenges to knowledge integration when working at the intersection of green infrastructure, ageing, health and well-being. Our findings—and the co-production process used to generate them—have wider significance for trans-disciplinary research into the benefits of the natural environment to human health and well-being as well as other complex and interconnected topics associated with global grand challenges.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01765-5.  相似文献   
662.
High-rocky-shore intertidal animals are predicted to be generally more vulnerable to climate warming than lower-shore species, because their thermal tolerances lie closer to maximum environmental temperatures (T e). However, this prediction is based on taxonomically and ecologically limited information. The present study investigated the effect of habitat use on climate warming vulnerability of the tropical high-shore snail, Echinolittorina malaccana (from Brunei Darussalam, 5°N), which aestivates in sun-exposed or shaded habitats. The thermal regimes of these habitats differed vastly, but snails showed similar daily energy consumption in either habitat, due to temperature-insensitive metabolism (TIM) between 35 and 46 °C in the sun-resting snails. However, maximum T e values in the shade and the sun were 35 and 46 °C, respectively, suggesting that sun-resting snails, which presently experience temperatures near the incipient lethal temperature range (46–56 °C), should be more threatened by further warming than shade-resting snails, which have an 11 °C ‘safety margin’. Thus, vulnerability of high-shore species to climate warming could be moderated by availability of shaded habitat, making predictions for these species more complex than previously realized.  相似文献   
663.
The objective of this study was to elicit community perceptions on the effectiveness of the CAMPFIRE programme, a community initiative, designed to benefit rural communities in Gonono ward in the Zambezi valley. Five villages and 76 respondents were selected from the ward using simple random sampling. Data collection included a structured questionnaire administered to households, semi-structured interviews with key informants, such as chiefs, headmen and local council staff, transect walks and participant observations. The results of the study revealed that, although the CAMPFIRE concept has been instrumental in creation of employment and infrastructure, the local community considers that no significant changes have occurred to their livelihoods. The findings suggest that the current model of wildlife conservation in Zimbabwe is not promoting total community participation. Future models need to focus on total involvement and independence from government structures. However, this can only happen when there is sufficient capacity building in communities on a wide number of issues, including general management, to ensure long-term sustainability.  相似文献   
664.
Although Late Pleistocene extinctions disproportionately affected larger mammalian species, numerous smaller species were also lost. To date, no satisfactory explanation has been presented to account for this pattern. Beginning with the assumption that human predation caused the extinctions, we offer and test the first such explanatory hypothesis, which is predicated on considering more realistic functional response forms (i.e., those that allow for predator interference or prey sharing). We then test the hypothesis via a one-predator, six-prey ecological model that maintains transparency, minimalism of design, and maximal constraint of parameters. Results indicate that altering assumptions about one cornerstone of ecological modeling (i.e., functional response) fails to produce qualitative differences in survival–extinction outcomes—even in conjunction with a wide range of capture efficiency permutations. This unexpected finding suggests that no reasonable form of predation alone is capable of producing the survival–extinction pattern observed. We conclude that the matter of causation and the conclusions of previous Late Pleistocene extinction models remain far less certain than many have assumed.  相似文献   
665.
Spatiotemporal Dynamics of Endangered Species Hotspots in the United States   总被引:2,自引:0,他引:2  
Abstract: Given limited resources, many researchers advocate focusing conservation efforts on hotspots, geographical areas with high numbers of species (i.e., richness), endemic species, rare or threatened species, and/or high levels of threat to species survival. The hotspot approach is an efficient and simple way to conserve species diversity, assuming that hotspots do not change over space or time. We tested whether hotspots change across space and time using a database of endangered and threatened species listed by the U.S. government from 1967 to 1999. We determined hotspots based on the cumulative set of species listed for three overlapping and successively longer time periods: 1967–1979, 1967–1989, and 1967–1999. We used minimum area complimentarity analysis, which selected the smallest set of areas (in our study, U.S. counties) needed to represent a chosen set of species. Over time, the number of endangered and threatened species in the United States increased from 76 in 1967 to 1123 in 1999. As the number of species increased over time, hotspots changed in two ways: the number of hotspots increased and the rank of hotspots shifted. Hotspots increased from 84 in 1979, to 166 in 1989, to 217 in 1999. Only 63 of these counties were designated as hotspots in all three periods. The remaining changes resulted from addition and deletion of counties as hotspots over time. Some counties were removed from the list or changed in relative rank from one time period to the next regardless of their rank. Counties added as hotspots could rank anywhere on the list, and they were not merely low-ranking counties added to represent one or a few species. Therefore, hotspots serve as a useful tool for guiding conservation efforts but, given their spatiotemporal variability, do not represent a final solution.  相似文献   
666.
The objective of this study was to characterize and understand the water quality of Boston's Muddy River prior to restoration, to help guide those activities and evaluate their success. We use a combination of monitoring, data analysis and mathematical modeling. The seasonal pattern of temperature, pollutant signatures (identified using a principal component analysis), correlations with precipitation and spatial patterns all point to a significant wastewater input at one of the outfalls and suggest significant receiving water impact. However, a quantitative analysis using a mathematical model (QUAL2K) suggests this source is not significant. Rather, internal loading from algae, sediment bed and waterfowl dominate the spatial pattern of water quality. These results suggest significant improvement can be expected from planned sediment dredging. The paper provides a case study of water quality assessment in the context of urban river restoration, and it illustrates the utility of combining monitoring and data analysis with modeling.  相似文献   
667.
Burning biomass fuels such as wood on indoor open-pit stoves is common in developing regions. In such settings, exposure to harmful combustion products such as fine particulate matter (PM(2.5)), carbon monoxide (CO) and polycyclic aromatic hydrocarbons (PAHs) is of concern. We aimed to investigate if the replacement of open pit stoves by improved stoves equipped with a chimney would significantly reduce exposure to PAHs, PM(2.5) and CO. Two stove projects were evaluated in Peru. Program A was part of the Juntos National Program in which households built their own stoves using materials provided. In Program B, Barrick Gold Corporation hired a company to produce and install the stoves locally. A total of 30 and 27 homes participated in Program A and B, respectively. We collected personal and kitchen air samples, as well as morning urine samples from women tasked with cooking in the households before and after the installation of the improved stoves. Median levels of PM(2.5) and CO were significantly reduced in kitchen and personal air samples by 47-74% after the installation of the new stoves, while the median reduction of 10 urinary hydroxylate PAH metabolites (OH-PAHs) was 19%-52%. The observed OH-PAH concentration in this study was comparable or higher than the 95th percentile of the general U.S. population, even after the stove intervention, indicating a high overall exposure in this population.  相似文献   
668.
The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO2); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO2 was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/−38 μg C kg−1 d−1). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO2 is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments.  相似文献   
669.
With 2020 energy targets set out by the EU fast approaching, the UK is trying to source a higher proportion of its energy from renewable resources. Coupled with this, a growing population and increasing trends in consumer demand have resulted in national waste loads increasing. A possible solution to both issues is energy-from-waste (EfW) technologies. Many studies have focused on municipal solid waste (MSW) as a potential feedstock, but appear to overlook the potential benefits of commercial and industrial waste (C&IW). In this study, samples of C&IW were collected from three North West waste management companies and Lancaster University campus. The samples were tested for their gross and net calorific value, moisture content, ash content, volatile matter, and also elemental composition to determine their suitability in EfW systems. Intra-sample analysis showed there to be little variation between samples with the exception two samples, from waste management site 3, which showed extensive variation with regards to net calorific value, ash content, and elemental analysis. Comparisons with known fuel types revealed similarities between the sampled C&IW, MSW, and refuse derived fuel (RDF) thereby justifying its potential for use in EfW systems. Mean net calorific value (NCV) was calculated as 9.47 MJ/kg and concentrations of sulphur, nitrogen, and chlorine were found to be below 2%. Potential electrical output was calculated using the NCV of the sampled C&IW coupled with four differing energy generation technologies. Using a conventional incinerator with steam cycle, total electrical output was calculated as 24.9 GWh, based on a plant operating at 100,000 tpa. This value rose to 27.0 GWh when using an integrated gasification combined cycle. A final aspect of this study was to deduce the potential total national electrical output if all suitable C&IW were to be used in EfW systems. Using incineration coupled with a steam turbine, this was determined to be 6 TWh, 1.9% of the national demand thereby contributing 6.5% towards the UK’s 2020 renewable electricity target.  相似文献   
670.
Geologic sequestration appears to be a technically feasible method of storing carbon dioxide in underground aquifers in order to lower greenhouse gas emissions into the atmosphere. The overall feasibility of geologic sequestration is still in question and as such, has been the focus of intense research over the past decade. Researchers have looked to the oil/gas industry and water well industry for lessons learned and technical knowledge, however, a better industry to emulate may well be the waste industry. Viewing geologic sequestration repositories as underground landfills has a great many benefits. First, there is a plethora of existing research and investigations that are directly analogous to geologic sequestration projects. Second, the regulatory framework is rather mature and can be easily adapted to serve geologic sequestration. This paper conducts an extensive literature search of the environmental, waste, and geologic sequestration literature to ascertain planning, design, and operational methodologies, lessons learned, and concepts that are directly useful for geologic sequestration to improve the technical and regulatory framework. Lastly, the paper uses a hypothetical underground landfill geologic sequestration site (ULGSS) in Florida, USA to discuss some of the findings and implications from the literature. It is concluded that there are a number of literature findings from the waste and environmental arena that should be adapted for geologic sequestration.  相似文献   
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