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The Ethical Contract as a Tool in Organic Animal Husbandry   总被引:1,自引:3,他引:1  
This article explores what an ethicfor organic animal husbandry might look like,departing from the assumption that organicfarming is substantially based in ecocentricethics. We argue that farm animals arenecessary functional partners in sustainableagroecosystems. This opens up additional waysto argue for their moral standing. We suggestan ethical contract to be used as acomplementary to the ecocentric framework. Weexpound the content of the contract and end bysuggesting how to apply this contract inpractice. The contract enjoins us to share thewealth created in the agroecosystem (by ourjoint contributions) by enjoining us to carefor the welfare and needs of the individualanimal, and to protect them from exploitation(just as human co-workers should not beexploited). The contract makes promoting goodanimal welfare a necessary condition forbenefiting farm animals. Animals for their partare guaranteed coverage under the contract solong as they continue to contribute to thesystem with products and services.  相似文献   
3.

Climate change is a global phenomenon that affects biophysical systems and human well-being. The Paris Agreement of the United Nations Framework Convention on Climate Change entered into force in 2016 with the objective of strengthening the global response to climate change by keeping global temperature rise this century well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 °C. The agreement requires all Parties to submit their “nationally determined contributions” (NDCs) and to strengthen these efforts in the years ahead. Reducing carbon emissions from deforestation and forest degradation is an important strategy for mitigating climate change, particularly in developing countries with large forests. Extensive tropical forest loss and degradation have increased awareness at the international level of the need to undertake large-scale ecological restoration, highlighting the need to identify cases in which restoration strategies can contribute to mitigation and adaptation. Here we consider Brazil as a case study to evaluate the benefits and challenges of implementing large-scale restoration programs in developing countries. The Brazilian NDC included the target of restoring and reforesting 12 million hectares of forests for multiple uses by 2030. Restoration of native vegetation is one of the foundations of sustainable rural development in Brazil and should consider multiple purposes, from biodiversity and ecosystem services conservation to social and economic development. However, ecological restoration still presents substantial challenges for tropical and mega-diverse countries, including the need to develop plans that are technically and financially feasible, as well as public policies and monitoring instruments that can assess effectiveness. The planning, execution, and monitoring of restoration efforts strongly depend on the context and the diagnosis of the area with respect to reference ecosystems (e.g., forests, savannas, grasslands, wetlands). In addition, poor integration of climate change policies at the national and subnational levels and with other sectorial policies constrains the large-scale implementation of restoration programs. The case of Brazil shows that slowing deforestation is possible; however, this analysis highlights the need for increased national commitment and international support for actions that require large-scale transformations of the forest sector regarding ecosystem restoration efforts. Scaling up the ambitions and actions of the Paris Agreement implies the need for a global framework that recognizes landscape restoration as a cost-effective nature-based solution and that supports countries in addressing their remaining needs, challenges, and barriers.

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4.
引言 莫日-瓜苏河位于纳斯吉拉斯州,海拔高1450m.流淌470km后,该河流注入圣保罗州的帕尔杜河.其流域总面积为1400km2,其中有86%位于圣保罗州,包括一个工业化地区[1].  相似文献   
5.
Contamination of wood waste with chromated copper arsenate greatly limits recycling opportunities for the wood waste as a whole. Separation of CCA-treated wood from other wood types is one means by which such contamination can be removed. The purpose of the current study was to evaluate two detector technologies for sorting CCA-treated wood from other wood types. The detector technologies evaluated included X-ray fluorescence spectroscopy (XRF) and laser induced breakdown spectroscopy (LIBS). The XRF detector system utilized in this study was capable of rapidly detecting the presence of CCA in painted wood, wet wood, heartwood, sapwood, and at portions of the wood containing knots. Furthermore, the XRF system was capable of distinguishing between CCA-treated wood and wood treated with alternative wood treatment preservatives, but was limited by the fact that it was not designed for on-line operation so tests were conducted in a batch mode on a conveyor. The analysis time used in this study (3 s) can be decreased significantly for an XRF system designed specifically for on-line operation. The LIBS system developed for this study was found to effectively identify CCA-treated wood for pieces ranging in thickness from 1 to 8 cm. High sorting efficiencies were noted when 10 laser shots were taken on a piece of wood. Furthermore, the LIBS system was found to be effective for identifying wood that has been coated with stains and paints in addition to identifying wood that has been CCA treated. The major drawback with the LIBS system developed in this study was the limited laser pulse energy. With an increase in laser pulse energy it is anticipated that the working focal length of the LIBS system can be increased to enable the monitoring of wood samples of more variable thicknesses. Limitations associated with analysis of very rotted pieces of wood and wet wood can also be overcome by using a higher pulse energy laser. Overall, both technologies show incredible promise for sorting CCA-treated wood from other wood types. The next recommended step would be to run an improved full-scale operation at one facility to document sorting efficiencies and fine-tune the improvements proposed in the current study. Such a study could potentially open-the-door for more widespread sorting of wood waste.  相似文献   
6.
Construction and demolition (C&D) wood frequently contains treated wood including wood treated with chromated copper arsenate (CCA). Many recycling options for such wood require that the product be essentially free of preservative chemicals. The objectives of this study were to document the characteristics of the wood waste stream and to evaluate the effectiveness of sorting methods for identifying treated wood. Sorting methods evaluated included visual sorting and visual sorting augmented with the use of PAN indicator stain and/or hand-held X-ray fluorescence (XRF) units. Experiments were conducted on two types of construction and demolition (C&D) wood: source separated loads containing only C&D wood and wood hand-picked from commingled loads of general C&D waste. Results showed that 77% of the treated wood was CCA-treated. For uncontaminated piles (<1% treated wood) of source separated C&D wood, visual sorting was found to effectively remove the small amounts of treated wood present. For piles of source separated wood that were contaminated (approximately 50% treated wood), visual sorts were not accurate and benefited from augmented sorting using PAN indicator stain. The handheld XRF devices were found to be effective for sorting commingled C&D wood, as PAN indicator stain was not as effective due to the excessive amount of surface dirt associated with commingled wood waste. Visual sorting of source separated wood was estimated to cost between US$21 to US$96 per metric ton. These costs depended upon the amount of treated wood and whether or not augmentation with PAN indicator was necessary. Visual sorting augmented with hand-held XRF units was estimated at US$113 per metric ton. The bulk of these costs were associated with labor. Future efforts should focus on reducing labor costs by mounting automated XRF units on conveyor systems.  相似文献   
7.
The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.  相似文献   
8.
Insects with two or more generations per year will generally experience different selection regimes depending on the season, and accordingly show seasonal polyphenisms. In butterflies, seasonal polyphenism has been shown with respect to morphology, life history characteristics and behaviour. In temperate bivoltine species, the directly developing generation is more time-constrained than the diapause generation, and this may affect various life history traits such as mating propensity (time from eclosion to mating). Here, we test whether mating propensity differs between generations in Pieris napi, along with several physiological parameters, i.e. male sex pheromone synthesis, and female ovigeny index and fecundity. As predicted, individuals of the directly developing generation—who have shorter time for pupal development—are more immature at eclosion; males take longer to synthesise the male sex pheromone after eclosion and take longer to mate than diapause generation males. Females show the same physiological pattern; the directly developing females lay fewer eggs than diapausing females during the first days of their life. Nevertheless, the directly developing females mate faster after eclosion than diapausing females, indicating substantial adult time stress in this generation and possibly an adaptive value of shortening the pre-reproductive period. Our study highlights how time stress can be predictably different between generations, affecting both life history and behaviour. By analysing several life history traits simultaneously, we adopt a multi-trait approach to examining how adaptations and developmental constraints likely interplay to shape these seasonal polyphenisms.  相似文献   
9.
Understanding threatened species diversity is important for long‐term conservation planning. Geodiversity—the diversity of Earth surface materials, forms, and processes—may be a useful biodiversity surrogate for conservation and have conservation value itself. Geodiversity and species richness relationships have been demonstrated; establishing whether geodiversity relates to threatened species’ diversity and distribution pattern is a logical next step for conservation. We used 4 geodiversity variables (rock‐type and soil‐type richness, geomorphological diversity, and hydrological feature diversity) and 4 climatic and topographic variables to model threatened species diversity across 31 of Finland's national parks. We also analyzed rarity‐weighted richness (a measure of site complementarity) of threatened vascular plants, fungi, bryophytes, and all species combined. Our 1‐km2 resolution data set included 271 threatened species from 16 major taxa. We modeled threatened species richness (raw and rarity weighted) with boosted regression trees. Climatic variables, especially the annual temperature sum above 5 °C, dominated our models, which is consistent with the critical role of temperature in this boreal environment. Geodiversity added significant explanatory power. High geodiversity values were consistently associated with high threatened species richness across taxa. The combined effect of geodiversity variables was even more pronounced in the rarity‐weighted richness analyses (except for fungi) than in those for species richness. Geodiversity measures correlated most strongly with species richness (raw and rarity weighted) of threatened vascular plants and bryophytes and were weakest for molluscs, lichens, and mammals. Although simple measures of topography improve biodiversity modeling, our results suggest that geodiversity data relating to geology, landforms, and hydrology are also worth including. This reinforces recent arguments that conserving nature's stage is an important principle in conservation.  相似文献   
10.
Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials.  相似文献   
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