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1.
Increase in waste sludge disposal is always seen as a problem from the point of production industry. However, it is clear that the reuse and recycle of sewage sludge could be a serious economic input. The most important action should be to determine the sludge characterizations and direct the producers towards appropriate reuse and recycling opportunities. In this study, reuse method was examined to produce coal briquette, which will constitute an example for waste sludge. In order to make use of the waste sludge, five different coal briquette samples were produced by mixing powdered coal and bitumen together with waste sludge, at different ratios. The overall results indicated that the sample named CB3 having 70% powdered coal, 20% waste sludge, and 10% bitumen was found to be the optimum coal briquette among the other samples produced. The proximate analysis of the optimum briquette sample was carried out according to the Turkish standards and regulations and it was found out that the produced briquette coal can have commercial value with a gross calorific value of 30.03 MJ/kg and 7.30% ash content.  相似文献   

2.
Three different sizes of hog farms were selected to analyze the carbon emissions reduction and the cost–benefit of three methane digester systems. The sizes of the digesters are 2,200, 2,200 and 800 m3, respectively. The sales of slaughter hogs from them are 50,000, 35,000 and 10,000 head, respectively. The carbon emissions reductions were 5,237, 4,017, and 1,334 tons, respectively. The results show that while the methane digester systems have a significant effect on carbon emissions reduction, it is difficult to operate the systems sustainably. If the carbon emissions reduction can be traded at high enough prices in the carbon offset markets, then the systems will be profitable and sustainable. Newly established China's domestic carbon offset market could provide this possibility, but more government support is needed. In addition, this study shows that scale economies make the digester adoption relatively more profitable for larger farms than smaller ones.  相似文献   

3.
Methane, coal and biomass are being considered as alternatives to crude oil for the production of basic petrochemicals, such as light olefins. This paper is a study on the production costs of 24 process routes utilizing these primary energy sources. A wide range of projected energy prices in 2030–2050 found in the open literature is used. The basis for comparison is the production cost per t of high value chemicals (HVCs or light olefin-value equivalent). A Monte Carlo method was used to estimate the ranking of production costs of all 24 routes with 10,000 trials of varying energy prices and CO2 emissions costs (assumed to be within $0–100/t CO2; the total CO2 emissions, or cradle-to-grave CO2 emissions, were considered). High energy prices in the first three quarter of 2008 were tested separately. The main findings are:
  • Production costs: while the production costs of crude oil- and natural gas-based routes are within $500–900/t HVCs, those of coal- and biomass-based routes are mostly within $400–800/t HVCs. Production costs of coal- and biomass-based routes are in general quite similar while in some cases the difference is significant. Among the top seven most expensive routes, six are oil- and gas-based routes. Among the top seven least expensive routes, six are coal and biomass routes.
  • CO2 emissions costs: the effect of CO2 emissions costs was found to be strong on the coal-based routes and also quite significant on the biomass-based routes. However, the effect on oil- and gas-based routes is found to be small or relatively moderate.
  • Energy prices in 2008: most of the coal-based routes and biomass-based routes (particularly sugar cane) still have much lower production costs than the oil- and gas-based routes (even if international freight costs are included).
To ensure the reduction of CO2 emissions in the long-term, we suggest that policies for the petrochemicals industry focus on stimulating the use of biomass as well as carbon capture and storage features for coal-based routes.  相似文献   

4.
5.
The paper reports the production of syngas from dry reforming of methane (DRM) over La1?xCexNi1?yFeyO3 (x, y = 0–0.4) perovskites. A series of La1?xCexNi1?yFeyO3 were designed by central composite design (CCD) and synthesized by a sol–gel auto combustion method. Artificial neural network (ANN) approach was used to determine the relationship between preparation and operational parameters on the performance of the catalysts in the DRM process. Nickel mole fraction, lanthanum mole fraction, calcination temperature, and reaction temperature were considered as input variables, and conversion of methane was considered as the output variable. An ANN model with nine neurons in the hidden layer was the suitable in predicting conversion of methane. The genetic algorithm (GA) was subsequently used to determine the optimal preparation condition for enhancing the conversion of methane. La0.6Ce0.4Ni0.99Fe0.01O3 catalyst, calcined at 756°C was obtained to be the most active catalyst owing to the optimal composition of nickel and lanthanum in the catalyst formulation.  相似文献   

6.
ABSTRACT

Central Appalachia's historical dependence on natural resource extraction industries has contributed to a long history of under- and uneven development, including trends of persistent poverty, cycles of unemployment, weakened local governance, environmental degradation, and severe social inequalities relative to the rest of the nation. Though these trends have been well documented at structural and community-levels, scholarship is more limited in assessing how the conditions of natural resource dependency may shape the everyday experiences of those who live in such regions and how those everyday experiences may illuminate challenges for future development. Employing an embedded case study design, this study examines how everyday environmental injustices may be experienced via community gardening activities, a sustainable development-oriented activity celebrated in urban locations but largely unexplored in rural environments. Drawing upon in-depth interviews with 43 gardening programme coordinators and participants, the findings demonstrate that everyday environmental injustices are experienced across four distinct, yet overlapping and mutually reinforcing, dimensions: natural, built, human health, and socioeconomic environments. These factors in turn constrain programme participation and beneficial programme outcomes, particularly for more disadvantaged households that are affected by chronic illness, geographic isolation, and environmental hazards. Although the interviewees viewed many of these challenges as further justification for pursuing grassroots initiatives like community gardening programmes, these constraints also interacted in a way that limited the success of these locally-oriented sustainable development efforts, particularly for individuals who are the most socially, economically, and environmentally marginalised.  相似文献   

7.
The use of landholder typologies to aid the development, implementation, and monitoring natural-resource management (NRM) policies and programs has increased considerably during the past decade. This article explores the potential for using such typologies for a variety of NRM and rural and regional development applications. Review of typology use further suggests that there is potential to refine the way that typologies are developed and applied to better aid NRM, farming systems analyses, and rural and regional development. Before typologies will be adopted more widely, a number of theoretical and methodologic issues must be addressed. These include the following questions: (1) Which criteria and methods should or can be used to classify landholders? (2) How should studies across spatial and temporal scales be integrated? (3) How should multiple and single industry studies be integrated to gain the most value from research? We argue that quantitative research techniques are well suited to provide an underlying structure for landholder typologies, and qualitative research techniques are useful for developing understanding of the nature of variation within and between landholder types. We argued further that because of the potential utility and breadth for the application of landholder typologies, a nested set of landholder typologies could be developed that are coordinated at the national, regional, and local geographic levels, with repeated measures used to track the evolution with time of landholder practices, management values, and socioeconomic characteristics.  相似文献   

8.
Mainstream currents within Christianity havelong insisted that humans, among all creatures, areneither fully identified with their physical bodiesnor fully at home on earth. This essay outlines theparticular characteristics of Christian notions ofhuman nature and the implications of this separationfor environmental ethics. It then examines recentefforts to correct some damaging aspects oftraditional Christian understandings of humanity'splace in nature, especially the notions of physicalembodiment and human embeddedment in earth. Theprimary goal of the essay is not to offer acomprehensive evaluation of Christian thinking aboutnature but rather to identify theological anthropologyas a crucial dimension of, and problem for, Christianenvironmental ethics.  相似文献   

9.
While various studies have compared metropolitan and rural residents' displays of environmentalism, recent shifts in the housing and energy markets make intra-metropolitan differences in urban and suburban attitudes and actions more interesting. The housing market crash and accompanying rise in fuel costs are prompting a return of centralisation to many communities and, it is believed, are drawing environmentally conscious residents downtown closer to work and play. Past research has found that this trend – demonstrated by a re-centralising housing market – was already underway, pre-crash, in Louisville, Kentucky over the “boom” period from 2000 to 2006. Drawing on original 2006 survey data for Louisville, this study regresses two components of environmentalism (behaviour and concern) on socio-demographics and residence. Findings show urbanites in Louisville are indeed significantly more environmentally friendly in their behaviour but not in their concern. Countering some claims, residents of single-family homes also exhibit significantly higher levels of environmental behaviour and concern than those residing in apartments and condominiums. Finally, in a surprise finding, recent movers from the suburbs to the city do not differ in their behaviour and are significantly less concerned about the environment than urbanites, suburbanites, and all metropolitan residents.  相似文献   

10.
Local food systems and farmers' markets across the USA have experienced unprecedented growth and development in the past 20 years. While scholarship has examined participant demographics and motives for engaging in farmers' markets, few studies have considered the coupled nature of those attending the markets with institutional governance systems used for market coordination. This study examined participation in farmers' markets under the framework of high and low market governance systems, specifically considering the demographics, values for local foods, motives for attending farmers' markets, and outcomes of the experience based on the dichotomous governance classification. Governance was characterized using four attributes: market rules or policies, paid employee(s), a rule governing geography of food origin, and affiliation with an organisation or agency. Our results suggest that market governance may impact (1) which consumers attend the market, (2) motives among those who attend the market, and (3) satisfaction outcome levels among market participants. By better understanding how the emerging governance system impacts who ultimately attends the market (and the outcomes of the experience), agencies coordinating farmers' markets and market managers can ultimately improve the market's reach and experience with greater intentionality.  相似文献   

11.
Inland water bodies are considered as integrated parts of the landscape and the monitoring of water quality and aquatic resources need to be addressed on a regional basis for optimal assessment and management. In this study, a simple stratified sampling scheme was applied to a mesoscale survey of western and northwestern Irish lakes, which was carried out to identify, based on the distribution patterns of phytoplankton biomass, potential associations between lake trophic state and land cover attributes. Phytoplankton community analysis was also performed to determine whether taxa associations reflected meteorology-linked aestival succession or specific spatial distributions. The assessment was based on the typology of hydrogeomorphological and land cover attributes of river catchments through ArcGIS analysis. Sampling was carried out in 50 lakes and during a 15-week period in summer 2009. Results showed a general longitudinal gradient in the trophic status of the lakes sampled, with a greater frequency of mesotrophic lakes in the eastern part of the study area where land cover is dominated by agricultural surfaces. Significant relationships (p < 0.010) were found between chlorophyll-a concentration and the proportion of river catchment surface covered by agriculture land and wetlands, findings which might be considered further as proxies for developing an eutrophication risk index. Multivariate analysis of phytoplankton community data clustered the sampled lakes into three assemblages, with ordination along axis 1 being significantly correlated to time and temperature (p < 0.006). There was greater frequency of occurrence of diatoms in lakes from cluster III (Kruskal–Wallis, p < 0.05, H = 6.34, df = 2, n = 49), concomitant to lower chlorophyll-a concentrations, lake surface temperatures and Secchi depths, reflecting meteorological conditions dominated by precipitations. Those results support the potential of mesoscale surveys to assess water quality variables and detect environmental patterns at regional scales.  相似文献   

12.
Thirteen metric tons of poultry litter are produced annually by poultry producers in the U.S. Poultry litter contains the sex hormones estradiol and testosterone, endocrine disruptors that have been detected in surface waters. The objective of this study was to evaluate the potential impact of poultry litter applications on estradiol and testosterone concentrations in subsurface drainage and surface runoff in irrigated crop land under no-till and conventional-till management. We conducted an irrigation study in fall of 2001 and spring of 2002. Four treatments, no-till plus poultry litter, conventional-till plus poultry litter, no-till plus conventional fertilizer, and conventional-till plus conventional fertilizer, were evaluated. Flow-weighted concentration and load ha−1 of the two hormones were measured in drainage and runoff. Soil concentrations of estradiol and testosterone were measured. Based on comparisons to the conventional fertilizer (and control) treatments, poultry litter did not add to the flow-weighted concentration or load ha−1 of either estradiol or testosterone in subsurface drainage or surface runoff. Significant differences were, however, observed between tillage treatments: flow-weighted concentrations of estradiol were greater for no-till than conventional-till plots of the June irrigation; and runoff loads of both estradiol and testosterone were less from no-till than conventional-till plots for the November irrigation. Although the differences between no-till and conventional-tillage appeared to affect the hydrologic transport of both hormones, the differences appeared to have inconsequential environmental impact.  相似文献   

13.
The fact that the artisanal and small-scale mining (ASM) sector in Ghana is driven largely by poverty means that the sector is a major source of livelihood for people in mining communities across the country. However, given the various social and environmental problems associated with the ASM sector, there is now an emerging consensus that the formalization of the sector would not only allow for these associated problems to be addressed but also ensures that the sector contributes to sustainable development and safeguard the livelihood of local communities. While a large body of extant literature has examined the challenges and opportunities facing the process of formalization, the question of the criminalization of the sector and its consequences for local livelihood has received only limited attention. Drawing from primary data collected during fieldwork in Ghana, this study examined the livelihood implications of the ban on galamsey in the Tarkwa-Nsuaem Municipality in South-Western Ghana from the perspectives of local communities and other key stakeholders. The study reveals that the ban on galamsey has imposed significant socio-economic hardships on the people and appears to be entrenching poverty rather than sustainable development. The study considers the theoretical and practical implications of the findings for sustainable livelihood enhancement in developing countries.  相似文献   

14.
15.
Colonial processes including the dispossession of indigenous lands and resources and the development of Western management institutions to govern the use of culturally important fish resources have served in many ways to marginalize indigenous interests within the United States fisheries. In recent years, several US fishery institutions have begun to develop policies that can confront this colonial legacy by better accommodating indigenous perspectives and rights in fishery management practices. This paper analyzes two such policies: the 2005 community quota entity program in Alaska which permits rural communities (predominantly Alaska Native villages) to purchase and lease commercial halibut fishing privileges and the 1994 State of Hawai?i community-based subsistence fishing area (CBSFA) legislation through which Native Hawaiian communities can designate marine space near their community as CBSFAs and collaborate with the state of Hawai?i to manage those areas according to traditional Hawaiian practices. The analysis reveals a striking similarity between the trajectories of these two policies. While they both offered significant potential for incorporating indigenous rights and environmental justice into state or federal fishery management, they have so far largely failed to do so. Environmental managers can gain insights from the challenges and potentials of these two policies. In order to introduce meaningful change, environmental policies that incorporate indigenous rights and environmental justice require a commitment of financial and institutional support from natural resource agencies, a commitment from indigenous groups and communities to organize and develop capacity, and careful consideration of contextual and cultural factors in the design of the policy framework.  相似文献   

16.
17β-estradiol and testosterone are naturally occurring steroids that co-occur in poultry litter. The effects of litter on sorption of these hormones to soil are not known. Sorption isotherms were developed for C-labeled testosterone and H-labeled estradiol in a Cecil sandy clay loam with and without poultry litter addition. The effect of applying the hormones alone (single-sorbate) or together (multisorbate) was also investigated. C-testosterone sorption in soil increased from 2 to 48 h and remained relatively constant thereafter. H-estradiol sorption in soil was relatively constant from 2 to 24 h and then decreased to 72 h. These differences may reflect transformation of the parent hormones to products with different solid-phase affinity. The maximum sorption coefficient () in soil for C-testosterone (20.2 mL g) was similar to that for H-estradiol (19.6 mL g) in single-sorbate experiments. When hormones were applied together, sorption of both hormones in soil decreased, but the C-testosterone (12.5 mL g) was nearly twice as large as the H-estradiol (7.4 mL g). We propose this resulted from competition between the hormones and their transformation products for sorption sites, with C-testosterone and its expected transformation product (androstenedione) being better competitors than H-estradiol and its expected transformation product (estrone). When poultry litter was mixed with soil, sorption increased for H-estradiol but decreased for C-testosterone. This may have been because poultry litter slowed the transformation of parent hormones. Our results show that poultry litter could have important effects on the mobility of estradiol and testosterone.  相似文献   

17.
Western North America is experiencing a dramatic expansion of piñon (Pinus spp.) and juniper (Juniperus spp.) (P-J) trees into shrub-steppe communities. Feature extracted data acquired from remotely sensed imagery can help managers rapidly and accurately assess this land cover change in order to manage rangeland ecosystems at a landscape-scale. The objectives of this study were to: (1) develop an effective and efficient method for accurately quantifying P-J tree canopy cover and density directly from high resolution photographs and (2) compare feature-extracted data to typical in-situ datasets used by land managers. Tree cover was extracted from aerial-photography using Feature Analyst®. Tree density was calculated as the sum of the total number of individual polygons (trees) within the tree cover output file after isolation using a negative buffer post-processing technique. Feature-extracted data were compared to ground reference measurements from Utah’s Division of Wildlife Resources Range Trend Project (DWR-RTP). We found that the proposed feature-extraction techniques used for measuring cover and density were highly correlated to ground reference and DWR-RTP datasets. Feature-extracted measurements of cover generally showed a near 1:1 relationship to these data, while tree density was underestimated; however, after calibration for juvenile trees, a near 1:1 relationship was realized. Feature-extraction techniques used in this study provide an efficient method for assessing important rangeland indicators, including: density, cover, and extent of P-J tree encroachment. Correlations found between field and feature-extracted data provide evidence to support extrapolation between the two approaches when assessing woodland encroachment.  相似文献   

18.
This article discusses environmental sustainability in aquaculture and its contribution to poverty alleviation, based on field studies in Sri Lanka and the Philippines. The aquaculture practices studied are the monoculture of the black tiger prawn (Penneaus monodon) and milkfish (Chanos chanos) and the polyculture of the two species together with the mud crab (Scylla serrata). Factors affecting economic viability, social equity and environmental impacts in aquaculture are discussed and used to illuminate local and regional differences between aquaculture in Sri Lanka and the Philippines. Findings indicate that the most significant difference is the level of participation by local people (i.e., people originating ≤10 km away from the farm location). In the Philippines, 84 % of the people involved in aquaculture are locals, whereas in Sri Lanka, 55% are outsiders. Whether differences between the two areas can be explained by analyzing regional conditions, which might have resulted in different aquaculture practices, is discussed. In Sri Lanka, semi-intensive shrimp monoculture is currently the most common practice, whereas in the Philippines, extensive shrimp/fish polyculture is more common. Previous studies, as well as fieldwork, indicate that extensive culture practices reduce environmental impacts and benefit local people more. Sustainability in aquaculture is, however, also dependent on the extent of mangrove conversion into ponds. As such, extensive and locally owned farms do not necessarily result in an all but sustainable situation. Keeping this in mind, it is discussed if extensive polyculture practices might result in a more sustainable aquaculture, both environmentally and socioeconomically.  相似文献   

19.
Sustainable development has emerged as a distinctive marker of place identity in addition to traditional markers such as buildings and spectacles. Climate change mitigation as a potential place brand, indicating sustainable development, is in focus of this article, comparing such efforts in three Swedish towns. Based on documentary studies and interviews, it demonstrates how one town has been successful in branding itself as “the Greenest City in Europe”, whereas mitigation efforts in two other towns are barely known outside the town halls. In the first case, a combination of material, symbolic, and institutional components has been decisive in establishing a brand with internal and external legitimacy. This case highlights the importance of a dedicated network of influential actors and a potent governance structure visualising the will of a town to make its climate mitigation efforts known. Despite similar material conditions, the two others come short on the symbolic and the institutional dimensions, although they may still have a potential for future success in terms of mitigation both in practice and as a marker of identity.  相似文献   

20.
The dominant discourse in 20th century UK food and agricultural policies of a liberal, free trade agenda was modified at the turn of the 21st to embrace ecological sustainability and “food security.” The latter term has a long international history; the relationship between issues of technical production and equality of distributional access are also much debated. The paper examines shifts in UK policy discourse in the context of international research, policy, and initiatives to promote food security, and highlights the implications for social justice in and through the food system.  相似文献   

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