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The aim of this paper is to determine whether the present generation should preserve non-human living things (plants, animals and other organisms) for future generations, even if (i) in the future all the contributions these organisms currently make to human survival in decent conditions were performed by adequate technology and (ii) future people's preferences were satisfied by this state of affairs. The paper argues it would be wrong to leave a world without non-human living plants, animals and other organisms to future generations, because such a world would fail to secure one of the conditions of future people’s autonomy, that is, availability of adequate options. Building upon Joseph Raz’s account of autonomy, the paper shows that the presence of non-human living organisms is part of an adequate range of options insofar as, to be adequate, options must meet a test of variety. According to Raz, options pass this test if they enable human agents to exercise a set of physical, affective, imaginative and cognitive capacities humans normally have an innate drive to exercise. The paper discusses empirical findings as well as psychological theories that provide support to the hypothesis that interactions with non-human living organisms enable human beings to develop and exercise these capacities by shaping these capacities in a special way, different from the way interactions with other environments do.  相似文献   
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Predicted climate warming is expected to have profound effects on bark beetle population dynamics in the southwestern United States. Temperature-mediated effects may include increases in developmental rates, generations per year, and changes in habitat suitability. As a result, the impacts of Dendroctonus frontalis and Dendroctonus mexicanus on forest resources are likely subject to amplification. To assess the implications of such change, we evaluated the generations per year of these species under three climate scenarios using a degree-day development model. We also assessed economic impacts of increased beetle outbreaks in terms of the costs of application of preventative silvicultural treatments and potential economic revenues forgone. Across the southwestern USA, the potential number of beetle generations per year ranged from 1–3+ under historical climate, an increase of 2–4+ under the minimal warming scenario and 3–5+ under the greatest warming scenario. Economic benefits of applying basal area reduction treatments to reduce forest susceptibility to beetle outbreaks ranged from 7.75/ha (NM) to7.75/ha (NM) to 95.69/ha (AZ) under historical conditions, and 47.96/ha (NM) to47.96/ha (NM) to 174.58/ha (AZ) under simulated severe drought conditions. Basal area reduction treatments that reduce forest susceptibility to beetle outbreak result in higher net present values than no action scenarios. Coupled with other deleterious consequences associated with beetle outbreaks, such as increased wildfires, the results suggest that forest thinning treatments play a useful role in a period of climate warming.  相似文献   
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The aim of this study was to describe the impact of re-vegetation on the restoration of microbial community structure and soil microbiological properties in sand dunes that had been affected by mining activity. Soil samples were collected during the dry and rainy seasons from a chronosequence (1, 9, 21 years) of re-vegetated dunes using a single preserved dune as a reference. The composition of the fatty acid methyl esters and soil microbial properties were evaluated. The results showed that the changes in microbial community structure were related to seasonal variations: biomarkers of Gram-positive bacteria were higher than Gram-negative bacteria during the dry season, showing that this group of organisms is more tolerant to these stressful conditions. The microbial community structure in the natural dune was less affected by seasonal variation compared to the re-vegetated areas, whereas the opposite was observed for microbiological properties. Thus, in general, the proportion of saprobic fungi was higher in the natural dune, whereas Gram-negative bacteria were proportionally more common in the younger areas. Although over time the re-vegetation allows the recovery of the microbial community and the soil functions, these communities and functions are different from those found in the undisturbed areas.  相似文献   
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As coastal development increases so too does the number of artificial floating and permanent structures. It has been postulated that because of their size, many houseboats are similar to permanent structures in that they shade a significant portion of the benthos and thereby limit production by benthic flora. On the other hand, these structures can benefit biotic communities by providing sites for attachment of organisms in a substrate-limited environment and both habitat and food sources for fish. In this study, we examined whether houseboats benefit or harm the ecological integrity of a typical seagrass dominated system, at La Parguera, Puerto Rico. We performed a benthic survey to compare the diversity and health of seagrasses under houseboats to that at control locations. Species diversity (0-0.79) varied significantly among sites, but this variability was not attributed to the houseboats. Rather, the variability appeared related to the proximity of the study locations to new development along the shoreline. Average seagrass blade density and length were 52.7 blades/m(-2) and 23.6 cm, respectively. Neither parameter differed between houseboat and control areas; however, both varied significantly among sites. In addition, boat hulls were heavily encrusted with invertebrates. The overall averages of species diversity and richness of sessile organisms on hulls of the houseboats were 1.13 and 4.83, respectively. Fish also utilized these structures. Our results indicate that houseboats did not directly harm the seagrass communities at La Parguera primarily because of sound environmental management of wastes and mooring techniques.  相似文献   
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In the wake of Hurricane Sandy and other recent extreme events, urban coastal communities in the northeast region of the United States are beginning or stepping up efforts to integrate climate adaptation and resilience into long-term coastal planning. Natural and nature-based shoreline strategies have emerged as essential components of coastal resilience and are frequently cited by practitioners, scientists, and the public for the wide range of ecosystem services they can provide. However, there is limited quantitative information associating particular urban shoreline design strategies with specific levels of ecosystem service provision, and research on this issue is not always aligned with decision context and decision-maker needs. Engagement between the research community, local government officials and sustainability practitioners, and the non-profit and private sectors can help bridge these gaps. A workshop to bring together these groups discussed research gaps and challenges in integrating ecosystem services into urban sustainability planning in the urban northeast corridor. Many themes surfaced repeatedly throughout workshop deliberations, including the challenges associated with ecosystem service valuation, the transferability of research and case studies within and outside the region, and the opportunity for urban coastal areas to be a focal point for education and outreach efforts related to ecosystem services.  相似文献   
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This review presents a summary of the main interactions that occur during the carbon dioxide (CO2) adsorption at the surface of steel slags with basic (CaO, MgO), amphoteric (Al2O3, Cr2O3, TiO2, MnO, iron oxides) and acidic (SiO2) oxides. The high content of metal oxides in steel slags gives them a great potential to adsorb CO2, reaching a saturation value of about 0.25 kg of CO2/kg of slag. CO2 is physisorbed and chemisorbed on the most of metal oxide types. Generally, the CO2 physisorption on the basic and amphoteric metal oxides involves an electrostatic interaction between the CO2 and the cation from the oxides while the CO2 chemisorption rather implicates the basic sites that acts as the electron donor, and which are associated with O2? ions localized at surface defects. These interactions result in the formation of carbonates (monodentates or unidentates and bidentates). The affinity of oxides for the CO2 and the carbonate formation principally depend of the strength and number of basic sites at their surface and varies as following: basic oxides > amphoteric oxides > acidic oxides. The basic metal oxides generally represent the best electron donors and thus the best CO2 adsorbents due to the high basicity and their great number of reaction sites. Hence, it appears that the surface structure of basic and amphoteric metal oxides which may favour their interaction with the CO2, as well as their basicity is the determinant factor contributing to the formation of carbonate species. The molecular analysis of CO2 adsorption on steel slag metal oxides will provide useful data to identify rate-controlling mechanisms and should be considered for the development of new effective methods for the capture of atmospheric CO2 emissions released from industries.  相似文献   
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Land use is rapidly expanding in the Greater Yellowstone Ecosystem, primarily from growth in the number of rural homes. There is a need to project possible future land use and assess impacts on nature reserves as a guide to future management. We assessed the potential biodiversity impacts of alternative future land use scenarios in the Greater Yellowstone Ecosystem. An existing regression-based simulation model was used to project three alternative scenarios of future rural home development. The spatial patterns of forecasted development were then compared to several biodiversity response variables that included cover types, species habitats, and biodiversity indices. We identified the four biodiversity responses most at risk of exurban development, designed growth management policies to protect these areas, and tested their effectiveness in two alternative future scenarios. We found that the measured biodiversity responses, including riparian habitat, elk winter range, migration corridors, and eight other land cover, habitat, and biodiversity indices, are likely to undergo substantial conversion (between 5% and 40%) to exurban development by 2020. Future habitat conversion to exurban development outside the region's nature reserves is likely to impact wildlife populations within the reserves. Existing growth management policies will provide minimal protection to biodiversity in this region. We identified specific growth management policies, including incentives to cluster future growth near towns, that can protect "at risk" habitat types without limiting overall growth in housing.  相似文献   
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