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591.
We develop a landscape stewardship classification which distinguishes between farmers’ understanding of landscape stewardship, their landscape values, and land management actions. Forty semi-structured interviews were conducted with small-holder (<5 acres), medium-holders (5–100 acres), and large-holders (>100 acres) in South-West Devon, UK. Thematic analysis revealed four types of stewardship understandings: (1) an environmental frame which emphasized the farmers’ role in conserving or restoring wildlife; (2) a primary production frame which emphasized the farmers’ role in taking care of primary production assets; (3) a holistic frame focusing on farmers’ role as a conservationist, primary producer, and manager of a range of landscape values, and; (4) an instrumental frame focusing on the financial benefits associated with compliance with agri-environmental schemes. We compare the landscape values and land management actions that emerged across stewardship types, and discuss the global implications of the landscape stewardship classification for the engagement of farmers in landscape management.  相似文献   
592.
The leather industry (tanneries) generates high amounts of toxic wastes, including solid and liquid effluents that are rich in organic matter and mineral content. Vermicomposting was studied as an alternative method of treating the wastes from tanneries. Vermicompost was produced from the following tannery residues: tanned chips of wet-blue leather, sludge from a liquid residue treatment station, and a mixture of both. Five hundred earthworms (Eisenia fetida) were added to each barrel. During the following 135 days the following parameters were evaluated: pH, total organic carbon (TOC), organic matter (OM), cation exchange capacity (CEC), C:N ratio, and chromium content as Cr (III) and Cr (VI). The results for pH, TOC and OM contents showed decreases in their values during the composting process, whereas values for CEC and total nitrogen rose, indicating that the vermicompost reached maturity. For chromium, at 135 days, all values of Cr (VI) were below the detectable level. Therefore, the Cr (VI) content had probably been biologically transformed into Cr (III), confirming the use of this technique as an advanced biological treatment. The study reinforces the idea that vermicomposting could be introduced as an effective technology for the treatment of industrial tannery waste and the production of agricultural inputs.  相似文献   
593.
Green radicalism among local environmental officials in Sweden is examined with the aims of theoretically elaborating on different dimensions of Green radicalism in the context of public administration, exploring the dimensionality of Green radicalism among officials, and examining the extent to which Green radicalism is associated with policy influence. Three types of Green radicalism are identified: Green ethics, Green institutional change, and Green activism. Survey data (N = 701) show that the three theoretical dimensions are present among officials, and that there is no negative association between radicalism and influence. It is primarily officials with Green activism beliefs who perceive themselves as able to influence policy. These findings suggest a need for more nuanced understanding of and further studies into the role of public administration in the quest for more radical Green reforms.  相似文献   
594.
Scholars of environmental injustice have pushed to see beyond the spatial distribution of environmental harms in studies of unwanted land uses. Building upon this work, this article examines how the complex geographies of environmental injustice play out in a coalition to prevent the construction of a coal-fired power plant in Surry County, Virginia. While spatially dispersed coalitions of negatively affected actors can strengthen efforts to prevent the construction of an unwanted land use, they can also perpetuate the environmental injustices surrounding it. To make this argument, particular attention is paid to the diverse reasons and ways differentially situated actors oppose an unwanted land use. It is demonstrated how the disparate concerns and differential tactics deployed by actors in coalitions against unwanted land uses are often embedded in and potentially contribute to longer histories of social injustice.  相似文献   
595.
在当前强调产业结构调整的政策背景下,产业有序转移必须以有利于或者加强环境保护为基本目标。环境规制差异造成了不同经济地域之间污染密集型生产的比较优势调整,强化了高污染产业进行生产区位选择的动机,以规避来自政府的环境监管。环境治理成本的不同是高污染企业区际转移的重要驱动因素,企业环境寻求策略推动了污染密集型生产由环境规制强度高的地区向环境规制松弛地区的转移。企业污染密集型生产的区际转移受到环境要素产品生产比较优势的明显影响,这些环境要素产品与区际环境规制差异、企业市场内部化战略以及污染密集型产品的生命周期密切关联。借鉴一般均衡分析框架,可以明晰企业环境寻求策略下污染密集型生产转移的内在机制。一方面,环境成本差异决定了非环境友好产品生产转移的意愿,高强度的环境规制使得企业生产的边际环境治理成本和平均环境治理成本提高,污染密集型生产外迁的动力加强,生产效率高的企业对环境规制强度更加敏感。污染密集型生产承接地提高环境规制强度能形成对环境负面影响的有力对冲,遏制环境恶化趋势。另一方面,合理的区际环境政策差异能在产业有序转移中发挥重要作用。合理设定区际环境规制级差与碳信征信系统建设,加强分类监管与行业节能减排,建立拟承接生产项目的效率筛选机制,提高区域市场开放程度、降低产业优惠政策所形成隐性市场保护等环境监管手段是保证欠发达地区通过产业承接实现跨越式发展的关键所在。  相似文献   
596.
中国环境质量拐点:基于EKC的实证判断   总被引:1,自引:0,他引:1  
促进环境质量改善是"十三五"时期实现绿色发展和最终全面建成小康社会的重要目标和任务。随着经济进入新常态和环境治理政策的强势推进,中国环境质量是否已经跨越峰值和进入持续改善的通道?本文基于环境库兹涅茨曲线这一理论工具,依据环境统计数据和国际经验事实判断中国是否到达环境库兹涅茨曲线的拐点和具备促使环境质量持续改善的经济特征。首先,应用中国各省份1998—2013年的面板数据,对人均收入水平与主要大气污染物排放的关系进行回归拟合发现,人均烟粉尘排放自1998年以来持续下降,人均二氧化硫、氮氧化物排放均在"十二五"中前期到达峰值。大部分东部省份已经越过环境库兹涅茨曲线的拐点,但环境质量改善仍然缓慢。多数中部省份处于峰值阶段,而西部省份大都处于经济增长与环境质量恶化的矛盾阶段。其次,基于污染物排放的驱动因素框架,将中国当前的经济特征与美、日、韩三国跨越环境库兹涅茨曲线拐点的经验进行比较,结论表明中国目前已基本具备了跨越环境库兹涅茨曲线拐点的经济驱动条件,但是相对滞后的城镇化进程将会导致污染物排放峰值的扁平化和波动性。以主要污染物排放在2014年的基础上削减30%—40%作为环境质量全面改善的转折点判断,中国环境质量将在2025年左右趋于全面改善。最后,为了促进环境质量全面改善,认为应该根据各地区经济发展与环境污染形势的不同,实施差别化环境治理政策。同时积极防范新一轮城镇化过程中的环境风险,进一步强化区域环境污染的协同治理。  相似文献   
597.
近年来,长三角地区灰霾天气持续增多,空气细颗粒物污染问题日益突出。基于2013年1月至2015年5月长三角地区及周边缓冲区内共214个空气质量监测站点PM2.5逐时监测数据,运用普通克里金插值方法,从年、季、月尺度上分析了PM2.5的空间分布格局和时间动态变化。结果表明:(1)2 a来,长三角地区PM2.5浓度空间分布明显呈现整体北部高南部低,局部地区略有突出的分布特征;长三角地区PM2.5浓度年均值为57.08μg/m3;其中,江苏省PM2.5的年均值为三省市最高,为65.84μg/m3;其次为上海市,年均值为53.87μg/m3;浙江省PM2.5的年均值较小,为51.53μg/m3。(2)从季节尺度分析,长三角地区PM2.5浓度变化表现出冬春季高,夏秋季低的变化趋势;这与区域内冬季风向来源、降水稀少、气象扩散条件差有着密切的关系; (3)长三角地区月浓度变化大致呈U形分布; 12月份PM2.5浓度最高; 3月份以后, PM2.5浓度开始呈逐步下降趋势;在5~9月份,区域PM2.5处于"U"字的谷底,其中6月份夏收时期秸秆焚烧、气象等因素导致PM2.5浓度有略微升高;进入10月份后迅速攀升,且11、12月份呈现持续升高态势。  相似文献   
598.
Value stream mapping (VSM) is a well-accepted tool within lean manufacturing concept which is often used for analysing and designing the flow of materials and information required to manufacture a product. However, the analysis is static and single product oriented, which fails to cope with either the variation of production plan or a multi-product environment. In addition, the environmental impact of a manufacturing system is highly associated with the dynamic consumption of energy and resources. Despite the recent integration of VSM with simulation or environmental studies (in the domain of energy efficiency), still neglected is the dynamic assessment of all the resources involved in a multi-product production environment. This paper presents a methodology for modelling multi-product manufacturing systems with dynamic material, energy and information flows with the aim to generate economic and environmental value stream maps (E2VSM). The proposed methodology is validated with an industrial case.  相似文献   
599.
Secondary arsenic minerals in the environment: A review   总被引:1,自引:0,他引:1  
Information on arsenic (As) speciation in solid materials is critical for many environmental studies concerned with As stability and/or mobility in natural As-impacted soils and mining or industrial sites contaminated by As. The investigation of these systems has provided evidence for a number of secondary As minerals that have often played a significant role in As mobility in the solid phase–water system. This paper presents a list of environmentally important secondary As minerals in contaminated soil and waste systems, summarizes the information about their origin, occurrence, environmental stability and thermodynamics, and proposes several important avenues for further investigation.  相似文献   
600.
This study has indicated that there is close relationship between development density and environmental quality; therefore, it is necessary to decide the form of development carefully beforehand. The form of development is shaped either by new development or urban renewal which is a major tactic nowadays adopted by the Hong Kong Government to improve the living condition of the citizens and the quality of the built environment. This study is limited to urban renewal and aims to find out the major urban design considerations for sustaining the environment. Through a questionnaire survey carried out in Hong Kong, the opinions of architects, planners, property development managers, and local citizens were sought and evaluated, and critical design factors for enhancing environmental sustainability of urban renewal projects are highlighted. The results derived from factor analysis indicated that certain design considerations should be incorporated for sustaining the urban environment. “Land Use Planning”, “Quality of Life”, “Conservation & Preservation”, “Integrated Design”, “Provision of Welfare Facilities”, and “Conservation of Existing Properties” were believed to be the significant underlying factors for achieving environmental sustainability of local urban renewal projects. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
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