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101.
This paper describes an integrative method for quantifying, analyzing, and comparing the effects of alternative rehabilitation approaches with visual preference. The method was applied to a portion of a major industrial area located in southern Italy. Four alternative approaches to rehabilitation (alternative designs) were developed and analyzed. The scenarios consisted of the cleanup of the brownfields plus: (1) the addition of ground cover species; (2) the addition of ground cover species and a few trees randomly distributed; (3) the addition of ground cover species and a few trees in small groups; and (4) the addition of ground cover species and several trees in large groups. The approaches were analyzed and compared to the baseline condition through the use of cost-surface modeling (CSM) and visual preference assessment (VPA). Statistical results showed that alternatives that were more ecologically functional for forest bird species dispersal were also more visually preferable. Some differences were identified based on user groups and location of residence. The results of the study are used to identify implications for enhancing both ecological attributes and visual preferences of rehabilitating landscapes through planning and design.  相似文献   
102.
Molasses-based distilleries are one of the most polluting industries generating large volumes of high strength wastewater called vinasse. Different processes covering anaerobic, aerobic as well as physicochemical methods have been employed to treat this effluent. This study evaluated the microbial communities present in the vinasse during different stages of its treatment by traditional and molecular methods. The analysis of the efficiency of each treatment was performed by physicochemical parameters and toxicity analysis. The treatment of vinasse was performed in the following steps: high flow fermentation; filtration; chemical flakes; low-flow fermentation; filtration; and neutralization. The physicochemical analysis in different stages of the vinasse treatment demonstrated that phases of treatment influenced the performance of the evaluated parameters. Among the 37 parameters, 9 were within the limits established by the Commission for Environmental Policy of Minas Gerais, Brazil (COPAM), especially BOD (96.7% of pollution reduction), suspended solids (99.9%), pH, copper (88%), iron (92.9%), and manganese (88%). Some parameters, even after treatment, did not fit the maximum allowed by legislation. The microbial population decreased reaching 3 log CFU/ml present in the steps of the flakes chemical and disinfection treatment of vinasse. Lactobacillus brevis and Pichia kudriavzevii were present in all stages of the treatments, showing that these microorganisms were resistant and demonstrated that they might be important in the treatment of vinasse. The vinasse showed a significant reduction of pollution load after the disinfection treatment however still should not be discarded into water bodies because the high values of tannins and sediment solids, but suggest the use of the effluent in the cooling coil during the distillation process of the beverage.  相似文献   
103.
An inventory of material and energy consumption during the construction and operation (C&O) of a typical sanitary landfill site in China was calculated based on Chinese industrial standards for landfill management and design reports. The environmental impacts of landfill C&O were evaluated through life cycle assessment (LCA). The amounts of materials and energy used during this type of undertaking in China are comparable to those in developed countries, except that the consumption of concrete and asphalt is significantly higher in China. A comparison of the normalized impact potential between landfill C&O and the total landfilling technology implies that the contribution of C&O to overall landfill emissions is not negligible. The non-toxic impacts induced by C&O can be attributed mainly to the consumption of diesel used for daily operation, while the toxic impacts are primarily due to the use of mineral materials. To test the influences of different landfill C&O approaches on environmental impacts, six baseline alternatives were assessed through sensitivity analysis. If geomembranes and geonets were utilized to replace daily and intermediate soil covers and gravel drainage systems, respectively, the environmental burdens of C&O could be mitigated by between 2% and 27%. During the LCA of landfill C&O, the research scope or system boundary has to be declared when referring to material consumption values taken from the literature; for example, the misapplication of data could lead to an underestimation of diesel consumption by 60–80%.  相似文献   
104.
Climate change is increasing the variability of rainfall, and thus the availability of water supplies in many areas of the world. These impacts are already being felt in the state of Victoria, Australia where a 12 year drought period was recently experienced. Restrictions to water use have been implemented, as one component of a broad policy approach to manage the drought. While anecdotal evidence suggests that the substitution of centralised water supplies is occurring, this has not been proven empirically. This paper reports results from a survey of households in Victoria regarding their use of alternative water sources. The study found that substitution is occurring. Garden watering is the purpose which has the highest rate of alternative water source use. In total 41.6% of respondents always, and 33.2% sometimes use an alternative water source for garden watering. The most commonly used alternative source of water for garden watering is water previously used in the laundry (30.7%). The alternative source of water used was found to vary depending on the purpose of the water use. High levels of satisfaction were found for all alternative water sources used. Several barriers were found to the use of alternative water sources, the main of which were: inflexibility of existing infrastructure, cost, policy, and housing status. The results have implications for water retailers, policy makers and governments in locations facing water shortage.  相似文献   
105.
In recent years, policy mechanisms to support a formalized artisanal and small‐scale mining (ASM) sector in sub‐Saharan Africa have gained increasing currency. Proponents of formalization argue that most social and environmental problems associated with the sector stem from the fact that ASM is predominantly unregulated and operates outside the legal sphere. This paper critically examines recent efforts to formalize artisanal and small‐scale mining in West Africa, drawing upon recent fieldwork carried out in Sierra Leone, Ghana and Mali. In exploring the sector's livelihood dimensions, the analysis suggests that bringing unregulated, informal mining activities into the legal domain remains a considerable challenge. The paper concludes by confirming the urgent need to refocus formalization strategies on the main livelihood challenges and constraints of small‐scale miners themselves, if poverty is to be alleviated and more benefits are to accrue to depressed communities in mineral‐rich regions.  相似文献   
106.
Alternative brominated flame retardants (BFRs) have become prevalent as a consequence of restrictions on the use of polybrominated diphenyl ethers (PBDEs). For risk assessment of these alternatives, knowledge of their metabolism via cytochrome P450 enzymes is needed. We have previously proved that density functional theory (DFT) is able to predict the metabolism of PBDEs by revealing the molecular mechanisms. In the current study, the reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane and structurally similar chemicals with the Compound I model representing the active site of P450 enzymes was investigated. The DFT calculations delineated reaction pathways which lead to reasonable explanations for products that were detected by wet experiments, meanwhile intermediates which cannot be determined were also proposed. Results showed that alkyl hydrogen abstraction will lead to bis(2,4,6-tribromophenoxy)ethanol, which may undergo hydrolysis yielding 2,4,6-tribromophenol, a neurotoxic compound. In addition, a general pattern of oxidation reactivity regarding the 2,4,6-tribromophenyl moiety was observed among several model compounds. Our study has provided insights for convenient evaluation of the metabolism of other structurally similar BFRs.  相似文献   
107.
/ We investigated the notion that successful negotiations require that all parties to the dispute must have a desire to bargain. This desire is most likely to be present when the dispute exhibits ripeness and each party believes a bargained solution is the most cost-effective way to resolve differences. Structured interviews of participants in six Federal Energy Regulatory Commission hydropower licensing consultations were conducted to determine the level of need to negotiate for each party. The findings indicate that a need to negotiate is a necessary, but not sufficient, condition for success. Several factors were associated with a need to negotiate: a weak BATNA (best alternative to a negotiated agreement); a salient issue; participants' sense of efficacy; a sense of inevitability; professional roles encouraging negotiation; and disputes about facts as opposed to disputes about values. Participants' need to negotiate fluctuated throughout the process and intensified when questions were ripe: i.e., critical issues were debated or the regulatory process required action.KEY WORDS: Alternative dispute resolution; Federal licenses; Federal Energy Regulatory Commission; Instream flow; Environmental planning  相似文献   
108.
This paper examines the challenges of achieving sustainable management of the world's largest mangrove forest, the Sundarbans (SMF) in Bangladesh. During the past two decades, conflicts between mangrove maintenance and the pressure to provide economic livelihoods to forest-dependent communities (FDCs) have emerged and persisted. The SMF is currently managed by the Bangladesh Forest Department (BFD) under a state property rights regime. This study explores an alternative property rights regime which includes participatory approaches and co-management with FDCs to achieve sustainability, both economically and environmentally. Focus group discussions and a survey were the methods used to assess the prospects. The study finds that the absence of a management partnership between the BFD and FDCs is mainly responsible for the policy failures to achieve sustainable management of the SMF. However, evidence is presented that a ‘co-management’ property rights regime cannot be established until FDC capacity is enhanced through the formation of community level institutions.  相似文献   
109.
旅游地可持续发展需要重点关注当地居民生计的可持续。以海螺沟景区为案例地,基于可持续生计框架构建了适用的生计资本评估指标体系,量化识别了景区农户可持续的生计方式,明确了影响两类脆弱性农户生计策略选择的主要因素。结果表明:在研究区六种生计方式中,采用均衡兼收型和旅游主营型策略的农户其生计资本水平最高,而传统务农型和务工型农户生计资本水平最低。不同生计策略类型的农户在空间上集聚分布。缺乏金融资本是影响传统务农型和务工型农户选择均衡兼收型生计策略的主要因素,而物质资本和社会资本的缺乏则对他们选择旅游主营型生计策略有显著的影响。此外,海拔、距公路和核心景点的距离也对农户生计策略的选择有重要影响。  相似文献   
110.
Despite widespread recognition of the major threat to tropical forest biological diversity and local food security posed by unsustainable bushmeat hunting, virtually no long‐term studies tracking the socioecological dynamics of hunting systems have been conducted. We interviewed local hunters and collected detailed hunting data to investigate changes in offtake and hunter characteristics over 10 years (2001–2010) in Dibouka and Kouagna villages, central Gabon, in the context of hunter recollections of longer term trends since the 1950s. To control for changes in hunter behavior, such as trap location and characteristics, we report hunting offtake data per trap. Our results suggest the hunting area was already highly depleted by 2001; local hunters reported that 16 large‐bodied prey species had become rare or locally extirpated over the last 60 years. Overall, we observed no significant declines in hunting offtake or changes in species composition from 2001 to 2010, and offtakes per trap increased slightly between 2004 and 2010. However, trapping distance from the villages increased, and there was a switch in hunting techniques; a larger proportion of the catch was hunted with guns in 2010. The number of hunters declined by 20% from 2004 to 2010, and male livelihood activities shifted away from hunting. Hunters with the lowest hunting incomes in 2004 were more likely than successful hunters to have moved away from the village by 2010 (often in response to alternative employment opportunities). Therefore, changes in trap success (potentially related to biological factors) were interacting with system‐level changes in hunter number and composition (related to external socioeconomic factors) to produce a relatively static overall offtake. Our results highlight the importance of understanding the small‐scale context of hunting to correctly interpret changes or apparent stasis in hunting effort and offtake over time. Cambio Social y Ecológico a lo Largo de Una Década en un Sistema de Cacería Aldeana, Gabón Central  相似文献   
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