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831.
以武汉中心城区的东沙湖流域为研究对象,以7项下垫面及3项降雨因子为影响因子,以18项河湖水环境因子为响应变量,基于冗余分析研究多尺度下两者之间的关系.结果表明:在所研究的10项影响因子中,硬质铺装面积率和河网水面率是东沙湖流域城市河湖水环境的主要影响因子,贡献率达0.703和0.652,城市道路面积率则是3000m及以外缓冲区尺度下的主要影响因子,贡献率达0.796,降雨的空间分布不是主要影响因子,贡献率低于0.371;影响因子对水环境影响的尺度效应与排水管网的有无和水文汇水单元尺度的大小密切相关;东沙湖流域的河湖水污染可归因于以硬质铺装为代表的不透水面上的面源污染和经由排水管网运移排放的点源污染,河网水面率则是改善水环境的关键因素.  相似文献   
832.
A strong increase in the demand for some commodities over the last decade will have a major impact on their future supply situation. Of increasing importance, therefore, is an assessment of a commodity's criticality, and especially its supply risk, by appropriate indicators. The literature has proposed numerous indicators of the supply risk. Here, we use the convenience yield of commodity futures as a supply risk indicator to address some of the major shortcomings of existing indicators, especially regarding their predictive power. This paper aims to test the applicability of the convenience yield as an indicator of a commodity's future supply risk. Therefore, we calculate historical convenience yields for 3-, 15-, and 27-month futures contracts for five major industrial metals (aluminum, copper, lead, nickel, and zinc) during the period 1999 to 2011. We compare the convenience yields at the beginning of the contract period to known indicators at maturity to find that the convenience yield has generally predictive power for the static stock lifetime (i.e., inventory volume/turnover) and future spot prices. Furthermore, we find that, with some restrictions, the convenience yield is an applicable indicator of a commodity's supply risk.  相似文献   
833.
It is commonly recognized that there are constraints to successful regional-scale assessment and monitoring of cumulative impacts because of challenges in the selection of coherent and measurable indicators of the effects. It has also been sensibly declared that the connections between components in a region are as important as the state of the elements themselves. These have previously been termed “linked” cumulative impacts/effects. These connections can be difficult to discern because of a complicated set of interactions and unexpected linkages. In this paper we diagnose that a significant cause of these constraints is the selection of indicators without due regard for their inter-relationships in the formulation of the indicator set. The paper examines whether the common “forms of capital”, i.e., natural (renewable and non-renewable), manufactured, social, human and financial capitals, framework is a potential organizing structure. We examine a large region in western NSW Australia where the predominant production systems are mining and grazing for production of wool, beef and lamb. Production in both is driven by consumption of a non-renewable resource, i.e., ore for mining and topsoil for grazing, the latter on the basis that loss rate estimates far exceed soil formation rates. We propose that the challenge of identifying connections of components within and between capital stores can be approached by explicitly separating stores of capital and the flows of capital between stores and between elements within stores, so-called capital fluxes. We attempt to acquire data from public sources for both capital stores and fluxes. The question of whether these data are a sufficient base for regional assessment, with particular reference to connections, is discussed. The well-described challenge of a comparative common currency for stores and fluxes is also discussed. We conclude that the data acquisition is relatively successful for stores and fluxes. A number of linked impacts are identified and discussed. The potential use of money as the common currency for stores and fluxes of capital is considered. The basic proposition is that replacement or preservation costs be used for this. We conclude that the study is sufficiently positive to consider further research in fully-coupled models of capital stores and fluxes.  相似文献   
834.
Despite several recent UK initiatives to promote renewable energy development at the local level, little research has been carried out to investigate public beliefs about aspects of local renewable energy development. This research attempted to address this gap. Empirical data were collected at the Awel Aman Tawe development in South Wales immediately before and after a public participation process. The results indicate that support for specific aspects of local energy development (partnership with local communities, local use of generated energy and profits put back into the local community) was consistently high across time, with support for local ownership at a slightly lower level, yet still high. Secondly, socio-demographical analyses indicated that personal factors such as respondents' age, gender and employment status were important in shaping several of these beliefs. Since UK renewable energy development has often been controversial and subject to delay, results suggest that the adoption of a locally embedded development approach by public and private sector stakeholders will be strongly supported by local people. The implications of the results are discussed in relation to existing industry best practice guidelines and recent policy initiatives.  相似文献   
835.
Many urban areas face conflicts between economic growth and environmental limitations. The ecological footprint is popular for communicating the global impacts of local activities, and if calculated at the local level, should be useful in emphasising the impacts of local planning, engaging community members, and allowing intra-community comparisons. We compare the two dominant methods for local ecological footprints: the compound and component methods. Both fail to adequately represent local footprints in North America. We propose a hybrid component method that takes advantage of the benefits of the component method but incorporates interpolation from the compound method to address data limitations. Grounded in Montreal, Canada, a city currently facing significant conflict between environment and growth, the study applies the hybrid method and discusses its potential benefits and limitations for community activists and planners.  相似文献   
836.
Abstract

A concept of occupational entropy is developed and related to the efficient use of mental (cognitive, emotional, and moral) resources and capacities. The corresponding “mind” indicators and pertinent response actions have proven essential for monitoring the state and projecting the behavior changes toward energy sustainability, as well as sustainable development in general.  相似文献   
837.
838.
This article examines the opportunities for fostering sustainable development through public sector sourcing from small- and medium-sized enterprises (SMEs). Buying from small businesses can make such contributions in a variety of forms, ranging from a contribution to local economic development through providing innovative green products and services, particularly in the food sector, to helping the public sector organisation to better align its operations with its community. Sourcing from small businesses also has implications for the governance of sourcing processes and can benefit from a partnership approach. Barriers to public sector sourcing from small businesses are discussed and suggestions made on how these can be overcome.  相似文献   
839.
The occurrence and abundance of the microfauna groups were compared with the physico-chemical and operational parameters of the Baoding Lugang Sewage Treatment Plant in China. Attached and crawling ciliates were the dominant groups of ciliates. Crawling ciliates and testate amoebae showed a strong association with effluent BOD5 (biochemical oxygen demand). Therefore, these two groups are likely to be useful bioindicators since their number decreased as the process produced poor quality effluent. Testate amoebae also had significant negative correlations with effluent TN (total nitrogen), NH4 -N, SS (suspended solids) and SVI (sludge volumetric index), which means that this group of ciliates may be indicators of good performance of the activated sludge system. Carnivorous ciliates and flagellates had significant positive correlations with SVI, suggesting that these two groups may be indicators of bad settlement conditions of sludge. As identification of the microfauna species is difficult and time-consuming, we recommend using microfauna functional groups to evaluate the performance of the activated sludge system.  相似文献   
840.
There is a mounting body of literature dealing generally with the dynamics of transitions of human systems towards sustainability and specifically with the different stages and processes of transitions. However, the question of why transition processes occur in the first place remains largely unexplained. This paper explores the concept of transition triggers, such as culture or material resource scarcity, and provides a theoretical framework to explain the emergence of a transition and its relation to recent developments in Spanish water policy. We adapt the general framework provided by current transition theory and gather empirical evidence and insights from processes occurring within the Spanish policy context and the Ebro river basin in particular. Our results show that the sole existence of biophysical limits to water use or development cannot explain the start of a possible sustainability transition in this domain in Spain. Changes in the existing water policies in the direction of sustainability were not ignited by people directly affected by water scarcities but by a coalition of sensitive agents, mostly from academia, NGOs and local constituencies, who managed to articulate new identities, integrate multiple sources of policy relevant knowledge, and develop new values under the umbrella of the new water culture movement.
Akgun IlhanEmail:
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