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991.
新疆塔里木河流域的胡杨资源在维持荒漠生态系统的协调稳定和保障绿洲生态安全等方面意义重大。运用GIS技术、多媒体技术、数据库管理技术的理论与方法,综合胡杨资源及其环境的遥感信息、文字信息及地图信息,建立集图象、图形、声音、文字为一体的计算机信息管理系统,为胡杨资源信息的存贮、查询、检索、更新、分析服务,同时,为胡杨资源合理利用及保护提供科学依据及决策支持。 相似文献
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993.
Brian D. Fox Brian P. Bledsoe Eleanor Kolden Matthew C. Kondratieff Christopher A. Myrick 《Journal of the American Water Resources Association》2016,52(2):420-442
Whitewater parks (WWPs) typically consist of instream structures that enhance recreational boating by constricting flow into a steep chute that generates a hydraulic jump in a downstream pool. Concerns have been raised that high velocities resulting from WWPs may be inhibiting fish movement during critical life stages. We evaluated the effects of WWPs on upstream fish passage by concurrently monitoring fish movement and hydraulic conditions at three WWP structures and three adjacent natural control (CR) sites in a wadeable river in northern Colorado. Fish movement was tracked with a network of Passive Integrated Transponder antennas over a 14‐month period. Individual fishes (n = 1,639), including brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss), were tagged and released within WWP and CR sites. Detailed hydraulic conditions occurring during the study period were evaluated with a fully 3D model. Results reveal the WWPs monitored in this study are not a complete barrier to upstream salmonid movement, but differences in passage efficiency from release location range from 29 to 44% in WWP sites and 37 to 63% for CR sites and the suppression of movement is related to body length. Small numbers of monitored nonsalmonids were inadequate to directly observe effects on their movement; however, it is highly probable that movement of smaller native fishes is also suppressed. Hydraulic modeling helps in the design of WWP structures that protect fish passage. 相似文献
994.
995.
Governmental intervention is essential to combat environmental pollution, a phenomenon classically explained as market failure, while market-based environmental policy instruments have provided cost-effective alternatives. By examining five pilot air pollution (sulfur dioxide) and water pollution (chemical oxygen demand) trading schemes in China through a market-based theoretical framework and extensive empirical analysis, this research analyzes where a state-market boundary is defined, whether the market is performing effectively, and, critically, what leads to underperformance. Constrained by policy design, policy conflicts, and excessive state intervention, the market has not played an effective and ‘decisive’ role, resulting in low market thickness for participants and transactions, market congestion on prices, and inadequate market safety for genuine emissions trading. Better emissions trading for conventional pollutants and CO2 requires better market-oriented rules, improved policy coordination, and stronger implementation while minimizing state intervention. 相似文献
996.
M. A. Vishnuganth Neelancherry Remya N. Selvaraju 《Journal of environmental science and health. Part. B》2017,52(5):353-360
Carbofuran (CBF) removal in a continuous-flow photocatalytic reactor with granular activated carbon supported titanium dioxide (GAC-TiO2) catalyst was investigated. The effects of feed flow rate, TiO2 concentration and addition of supplementary oxidants on CBF removal were investigated. The central composite design (CCD) was used to design the experiments and to estimate the effects of feed flow rate and TiO2 concentration on CBF removal. The outcome of CCD experiments demonstrated that reactor performance was influenced mainly by feed flow rate compared to TiO2 concentration. A second-order polynomial model developed based on CCD experiments fitted the experimental data with good correlation (R2 ~ 0.964). The addition of 1 mL min?1 hydrogen peroxide has shown complete CBF degradation and 76% chemical oxygen demand removal under the following operating conditions of CBF ~50 mg L?1, TiO2 ~5 mg L?1 and feed flow rate ~82.5 mL min?1. Rate constant of the photodegradation process was also calculated by applying the kinetic data in pseudo-first-order kinetics. Four major degradation intermediates of CBF were identified using GC-MS analysis. As a whole, the reactor system and GAC-TiO2 catalyst used could be constructive in cost-effective CBF removal with no impact to receiving environment through getaway of photocatalyst. 相似文献
997.
Benedict E Singleton 《环境政策》2017,26(6):994-1014
Since 1990, Elinor Ostrom’s design principles for common property resource (CPR) institutions have been highly influential, offering a counter to pessimistic arguments about resource users’ prospects of cooperating to manage CPRs sustainably. However, the theoretical underpinnings of Ostrom’s theory have been criticised: as unfairly negative towards macro-level interventions; as utilising an overly narrow conceptualisation of rationality; and under appreciative of the role of power. These criticisms are examined using insights drawn from the theory of sociocultural viability (cultural theory, for short), a theory of plural rationality related to context. Utilising the case of Faroese whaling, the research aim is to assess the extent that cultural theory ameliorates criticisms laid at Ostrom’s design principles. It finds that Ostrom’s research trajectory was reaching the limits of methodological individualism’s ability to grasp rational behaviour and suggests the design principles may in effect be integrated with cultural theory. 相似文献
998.
Sharon Prendeville Grit Hartung Clare Brass Erica Purvis Ashley Hall 《International Journal of Sustainable Engineering》2017,10(4-5):272-288
AbstractMakerspaces – open access design and fabrication workshops – provide new contexts for design practice through ‘distributed production’. The global community of makerspaces has evolved quickly and in turn, substantial hype is attributed to its potential for radical sustainable innovation. In this article, we explore this potential in the context of the new ‘circular economy’ agenda. We focus the research on the critical role of makerspace managers/founders who are recognised as gatekeepers to circular practices. The research method is action-led including expert interviews (academics and founders/managers) as well as two generative context-mapping workshops, run at selected makerspaces in collaboration with their founders/managers. We unearth everyday ‘how-to’ guidance to interweave circular practices within makerspaces from the outset by: fostering an enabling culture; building local connections; nurturing individual/community capacities; and stimulating practical know-how. However, while the research reveals immense opportunities to cultivate circular literacy from within makerspaces, the prospects to ask more profound questions about our economy, through makerspace practices, are found to be compromised by day-to-day concerns. The insights from this research can act as a starting point for future work in this emerging research area. 相似文献
999.
Gül Tekin Temur 《International Journal of Sustainable Engineering》2017,10(6):358-383
Many developing countries such as Turkey are still making an effort on building an infrastructure for waste of electrical and electronic equipment (WEEE) reverse logistic network design (RLND) processes. It is obvious that policies/laws/regulations related to WEEE management provide a sustainable framework for implementation in the RLND. The question is here: Does the implementation of WEEE directives make sense in terms of reducing the total cost of the network in the long term? This study aims to compare regulatory and non-regulatory situations of WEEE RLND in developing countries by formulating two models named as ‘regulatory’ and ‘non-regulatory’. Model 1 is considered as sustainable with economic, environmental and social goals, and the quotas imposed by the environmental directive are taken into consideration as the data of product return amount. In Model 2, only economic goal is considered, and product return amount is forecasted using Artificial Neural Network (ANN). A case study is conducted in a recycling company in order to evaluate performance of the proposed models. This study contributes to the relevant literature by (1) comparing the regulatory and non-regulatory situations RL models explicitly and (2) proposing ANN model to forecast EEE product return or WEEE quantity for non-regulatory situation. 相似文献
1000.
Maria Calero-Pastor Fabrice Mathieux Daniel Brissaud Jo Dewulf 《International Journal of Sustainable Engineering》2017,10(6):313-325
The design of heating, ventilation and air conditioning systems is still a challenging engineering task which requires experienced and informed decision-making. These systems have a great energy-saving potential at the system level rather than at the level of the individual products of which they are composed. European environmental product policies have been very useful in facilitating a homogeneous rating scheme which can be used to compare the energy performance of different products that provide the same service. This paper proposes a simplified design method which uses the performance of components that are regulated by European product policies to obtain the overall performance of heating systems in residential buildings. It is a flexible method and allows different product configurations to be assessed so as to optimise the system performance during the design phase. The method is tested on a real case study with domestic hot water and space heating systems. The case study shows the potential for improving the heating systems according to the performance levels of its products currently available in the market. Results of the domestic hot water system show that upgrading its storage tank to the maximum energy class (A+) could bring the highest energy savings ( 4162 kWh/y). 相似文献