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621.
随着我国工业化、城市化和机动化的高速发展,大气环境质量越来越受民众关注,我国已建成国控—省控—市控—县控四级环境空气自动监测网络,监测项目包括SO2、NO2、CO、O3、PM2.5和PM10.基于2018年绵阳市环境空气监测数据、颗粒物化学组分及气象资料分析上述6个监测项目年均、季度、月均、日均及每日最大小时浓度变化特征,并进一步探讨污染物浓度与气象条件的相关性,结合颗粒物化学组分对产生原因进行剖析.结果表明:绵阳市冬季环境空气质量较差,夏季相对较好.Pearson相关性分析表明:SO2、NO2、CO和颗粒物(PM2.5和PM10)之间存在显著相关性,冬季PM2.5与SO2、NO2的相关系数分别为0.610和0.635,PM10与SO2、NO2的相关系数分别为0.655和0.655,颗粒物主要化学组分为硫酸盐、硝酸盐、铵盐和二次有机气溶胶,颗粒物二次转化尤为明显,冬季需重点管控颗粒物;春季和夏季O3与PM2.5、PM10呈显著正相关,需做好颗粒物和O3的协同管控.O3每日最大小时浓度多集中在13:00?—?18:00,其他污染物每日最大小时浓度多集中于08:00?—?12:00和20:00?—?24:00,同时NO2在20:00?—?24:00出现每日最大小时浓度的频次占67.1%,控制机动车等污染源排放尤为重要. 相似文献
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623.
624.
Developing sustainable products and services 总被引:4,自引:0,他引:4
In light of increasing pressures to adopt a more sustainable approach to product design and manufacture, the requirement to develop sustainable products is one of the key challenges facing industry in the 21st century. Hence, the concept of developing sustainable products as well as services is evolving as a key element of Cleaner Production. Sustainable product development initiatives (mainly through eco-design) have been evolving for some time to support companies develop more sustainable products. Ireland has been running the highly successful Environmentally Superior Products (ESP) initiative that supports industrial companies to incorporate a more sustainable approach to the development of products and/or services. The lessons learned from the ESP and other global Sustainable Product and Service Developments in industry and research, are being used to develop a method for effective sustainable product and/or service development (SPSD) in industry. The method is designed to provide pragmatic guidance to business and industry for developing sustainable products and services as well as incorporating this approach within existing corporate strategy, cleaner production and product development systems. This method is being developed by the authors at the Environmental Policy and Management Group (EPMG), Department of Environmental Science and Technology, Imperial College London, UK in conjunction with industry and practitioners. The method provides a framework for implementing SPSD throughout the entire lifecycle of a product and/or service. It can be used to identify, assess and implement the options for optimum sustainability in the design and development of a product and/or service. This paper describes the key features of this method. 相似文献
625.
The Oxford Commission on Sustainable Consumption aims to promote debate and action to achieve sustainable consumption. It has met four times since it was established in 1999. Commission members have undertaken a number of projects around the world, working with communities to explore pathways to more sustainable consumption. This paper summarises the Commission’s progress and the messages emerging from its work. Current consumption trends are supported by a number of social trends, including individualisation, the spread of the market ethos, urbanisation, globalisation, and the increasing awareness of risk and uncertainty. However, these trends contain the seeds of their own limitation. In particular, increasing discourse about ethics and social goals may be the key to a shift towards more sustainable consumption. 相似文献
626.
This paper proposes an integrated ecological, economic and social model to assist sustainable rural development in villages in Bangladesh. In the model, renewable energy technologies (RETs) create income-generating activities for male landless and marginal farmers and for women from such households, while reducing environmental problems, like deforestation and indoor air pollution from cooking with poor-quality fuels. Because of the high capital costs of RETs, the model proposes an extension of the well-known micro-credit approach developed by such NGOs as the Grameen Bank and BRAC. With the assistance of an External Agency composed of NGO, business, government and university representatives, such groups of villagers would form Village Organizations, comprising cooperatives or other forms of business, borrow money from a bank or large NGO, and purchase a RET based on biogas, solar or wind, depending upon location. By selling energy to wealthier members of the village, the Village Organizations would repay their loans, thus gaining direct ownership and control over the technology and its applications. 相似文献
627.
建立我国战略环境评价理论与方法体系 总被引:29,自引:0,他引:29
战略环境评价是环境影响评价在战略层次上的应用,是具体落实可持续发展战略的重要工具。在分析其现实意义的基础上,提出我国战略环境评价理论与方法体系的主要研究内容,就建立我国战略环境评价理论与方法提出建议。 相似文献
628.
J.R. Schramski B.C. Patten C. Kazanci D.K. Gattie N.N. Kellam 《Ecological modelling》2009,220(22):3225
The Reynolds transport theorem (RTT) from mathematics and engineering has a rich history of success in mass transport dynamics and traditional thermodynamics. This paper introduces RTT as a complementary approach to traditional compartmental methods used in ecological modeling and network analysis. A universal system equation for a generic flow quantity is developed into a generic open-system differential expression for conservation of energy. Nonadiabatic systems are defined and incorporated into control volume (CV) and control surface (CS) perspectives of RTT where reductive assumptions in empirical data are then formally introduced, reviewed, and appropriately implemented. Compartment models are abstract, time-dependent systems of simultaneous differential equations describing storage and flow of conservative quantities between interconnected entities (the compartments). As such, they represent a set of flexible and somewhat informal, assumptions, definitions, algebraic manipulations, and graphical depictions subject to influence and selectively parsed expression by the modeler. In comparison, RTT compartment models are more rigorous and formal integro-differential equations and graphics initiated by the RTT universal system equation, forcing an ordered identification of simplifying assumptions, ending with clearly identified depictions of the transfer and transport of conservative substances in physical space and time. They are less abstract in the rigor of their equation development leaving less ambiguity to modeler discretion. They achieve greater consistency with other RTT compartment style models while possibly generating greater conformity with physical reality. Characteristics of the RTT approach are compared with those of a traditional compartment model of energy flow in an intertidal oyster-reef community. 相似文献
629.
A Markov model for assessing ecological stability properties 总被引:1,自引:0,他引:1
Ecological systems are frequently modeled as dynamic systems. It is natural then to use the techniques of dynamic systems theory to analyze such models. However, the methods and results that are produced by dynamic systems theory do not always capture the aspects of ecological systems that are of greatest interest to managers and decision-makers. We identify some of the challenges of using dynamic systems theory to explore ecological systems and propose an alternative approach that emphasizes the understanding of transient effects in light of uncertainty and variability. We illustrate this method by an examination of a model for phosphorus levels in fresh water lakes. 相似文献
630.
Andrea L. Jaeger Miehls Doran M. Mason Kenneth A. Frank Ann E. Krause Scott D. Peacor William W. Taylor 《Ecological modelling》2009,220(22):3194
Exotic species invasion is widely considered to affect ecosystem structure and function. Yet, few contemporary approaches can assess the effects of exotic species invasion at such an inclusive level. Our research presents one of the first attempts to examine the effects of an exotic species at the ecosystem level in a quantifiable manner. We used ecological network analysis (ENA) and a social network analysis (SNA) method called cohesion analysis to examine the effect of zebra mussel (Dreissena polymorpha) invasion on the Oneida Lake, New York, USA, food web. We used ENA to quantify ecosystem function through an analysis of food web carbon transfer that explicitly incorporated flow over all food web paths (direct and indirect). The cohesion analysis assessed ecosystem structure through an organization of food web members into subgroups of strongly interacting predators and prey. Our analysis detected effects of zebra mussel invasion throughout the entire Oneida Lake food web, including changes in trophic flow efficiency (i.e., carbon flow among trophic levels) and alterations of food web organization (i.e., paths of carbon flow) and ecosystem activity (i.e., total carbon flow). ENA indicated that zebra mussels altered food web function by shunting carbon from pelagic to benthic pathways, increasing dissipative flow loss, and decreasing ecosystem activity. SNA revealed the strength of zebra mussel perturbation as evidenced by a reorganization of food web subgroup structure, with a decrease in importance of pelagic pathways, a concomitant rise of benthic pathways, and a reorganization of interactions between top predator fish. Together, these analyses allowed for a holistic understanding of the effects of zebra mussel invasion on the Oneida Lake food web. 相似文献