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941.
Abstract

Building ecocities becomes an objective requirement for sustainable development. This article discusses the relationship between sustainable development and sustainable urban development. On the basis of discussing the sigificance of sustainable urban development and that of an eco-city from different perspectives, it suggests several management strategies for developing an eco-city, a desirable sustainable urban model.  相似文献   
942.
Since 1986, when green oysters occurred due to the copper and organic pollution in the Charting coastal area, the government banned all maricultural activity. It has been claimed that growing algae in a polluted environment may clean the water of pollutants and restore the marine ecosystem. to test this hypothesis, in the Charting coastal area a three-year programme (from August 1992 to July 1995) was carried out. the survey programme included environmental components such as salinity, temperature, pH, dissolved oxygen, biological oxygen demand (BOD), particulate organic carbon (POC), heavy metals and ecological indicators such as nutrients, chlorophyll-a, primary productivity. in the first year study, the environmental background data collected was used to select the suitable season and locations for growing large algae transferred from the laboratory to the field study area. Since September 1993, various species of large algae have been cultured. Although some of the growing algae were damaged by a typhoon in August 1994, the impact of the growing algae on the environmental conditions in the area has been monitored throughout. Elsewhere, we have reported that in the algae growing area higher dissolved oxygen with lower values of BOD and POC were found, and the concentrations of heavy metals in both water and sediments decreased. the purpose of this paper is to evaluate the possible impact of growing large algae on the ecological conditions in Charting coastal waters through the period from August 1983 to May 1995. As a result of the positive results obtained, large amounts of algae have again been cultured in the same area during the period from April 29 to May 25, 1995. We expect that inorganic and organic pollutants will be reduced by the algal growth, oyster mariculture will be restored and finally, the fishery resources potential will be increased.  相似文献   
943.
The stages of ontogeny and morphogenesis of the common chicory were characterized on the basis of long-term observations. A comparative analysis of seed productivity was performed, and the pool of viable seeds in the soil was determined. The ecological–cenotic relationships and the types of population strategy of the species were estimated.  相似文献   
944.
《淮河流域可持续发展战略研究》采取系统科学的方法,提出了较为完整的淮河流可持续发展战略体系,既是中国水利事业步入“大水利”举措的尝试,也弥补了从整体上研究中国大河流域可持续发展战略的不足,对于其他大河流域的可持续发展战略研究具有借鉴意义。  相似文献   
945.
Managing risk by adapting long-lived infrastructure to the effects of climate change must become a regular part of planning for water supply, sewer, wastewater treatment, and other urban infrastructure during this century. The New York City Department of Environmental Protection (NYCDEP), the agency responsible for managing New York City’s (NYC) water supply, sewer, and wastewater treatment systems, has developed a climate risk management framework through its Climate Change Task Force, a government-university collaborative effort. Its purpose is to ensure that NYCDEP’s strategic and capital planning take into account the potential risks of climate change—sea-level rise, higher temperature, increases in extreme events, changes in drought and flood frequency and intensity, and changing precipitation patterns—on NYC’s water systems. This approach will enable NYCDEP and other agencies to incorporate adaptations to the risks of climate change into their management, investment, and policy decisions over the long term as a regular part of their planning activities. The framework includes a 9-step Adaptation Assessment procedure. Potential climate change adaptations are divided into management, infrastructure, and policy categories, and are assessed by their relevance in terms of climate change time-frame (immediate, medium, and long term), the capital cycle, costs, and other risks. The approach focuses on the water supply, sewer, and wastewater treatment systems of NYC, but has wide application for other urban areas, especially those in coastal locations.  相似文献   
946.
分析了面临的历史性检验,深刻理解了云南省委提出的建设理念,认为应从战略和全局高度创新环保新形象,建设富裕文明开放和谐云南,必须完成“十一五”环保“刚性”指标。  相似文献   
947.
江苏省高资源消耗型产业甄别与竞争力评价研究   总被引:1,自引:0,他引:1  
江苏省高资源消耗型产业经营模式粗放。行业产值贡献份额小,资源占用份额大。经济发展和人口、资源、环境的矛盾十分突出,因此。高资源消耗型产业的甄别与合理调控是江苏建设节约型社会的关键。本文采用了资源消耗指数法甄别出江苏省12种高资源消耗型产业。研究表明:高资源消耗型产业在江苏省工业中占据绝对的比倒优势。有些产业甚至是江苏省经济发展的主要支柱产业:针对江苏高资源消耗型产业发展的特点。从经济实力、资本实力、对外开放水平和资源节约实力4个方面构建了产业竞争力评价指标体系。采用因子分析法对高资源消耗型产业的综合竞争力进行了评价。研究结果表明,除化学原料及化学制品制造韭、纺织韭和电力、燃气及水的生产供应韭竞争力较强外。其他类别的高资源消耗型产业的综合竞争力普遍偏低;最后从产业发展结构调整、重点行韭发展规划和行韭管理优化3个方面对江苏高资源消耗产韭的可持续发展提出调控策略。  相似文献   
948.
洪水风险分析及近期防洪策略   总被引:4,自引:0,他引:4  
向立云 《灾害学》1992,7(3):79-83
目前我国主要江河流域大都只能防御常遇洪水,近10a内这种状况不会有大的改观。因此,我国近期防洪的重点是尽量减少主要江河流域中下游精华地区在出现超标准洪水时的损失。实现这一目标的有效途径,是在洪水风险分析的基础上,制定并实施防御超标准洪水的预案。而减少伤亡最有效的方法是控制山洪高风险区的开发和建立预警报系统。  相似文献   
949.
The anaerobic biodegradability of wastewaters from different chemical plants was determined by an integrated test strategy consisting of an anaerobic toxicity test, a static anaerobic biodegradation test and a continuously operated fixed bed reactor test. This integrated procedure offered a useful tool for screening wastewaters for anaerobic biodegradability. Four different wastewaters were tested for anaerobic toxicity and biodegradability. One wastewater was used in subsequent testing in a fixed bed reactor which aimed to illustrate a potential design of an anaerobic treatment plant.  相似文献   
950.
碳减排目标是实现减排任务的重要保障.为探讨差异化减排目标对区域产业部门经济与碳减排的影响,以在我国具有特定区位条件(“21世纪海上丝绸之路”的重要节点)和经济发展现状(相对较为落后)的广西壮族自治区为主要研究区域,构建包括广西壮族自治区和我国其他地区〔除广西壮族自治区以外的其他省(自治区、直辖市),但不含港澳台地区,下同〕在内的可计算的一般均衡模型,设定P55C65、P75C65、P65C55、P65C65、P65C75(“P”表示广西壮族自治区,“C”表示我国其他地区,“55”“65”“75”分别表示碳减排目标依次为55%、65%、75%)和基准情景(无减排目标),研究区域间宏观经济和微观产业部门指标之间的相互影响.结果表明:①无差异情景(P65C65)下,广西壮族自治区农林牧渔业2030年的产值为741.17×108元,比基准情景下降0.19%;我国其他地区电子设备制造业的产值为33 457.49×108元,比基准情景下降2.00%.对广西壮族自治区碳排放贡献较大的产业部门主要为食品制造业、金属冶炼及压延业和服务业,而我国其他地区碳排放主要受电力热力生产的影响.②差异化情景下,这两个区域的金属冶炼及压延部门受减排约束影响均较明显.相比无差异情景,P75C65情景下,广西壮族自治区2030年金属冶炼及压延部门的出口总值和省际输出分别降至17.55×108和186.32×108元,分别下降了6.80%和1.65%;本地供应和产出分别降至358.72×108和562.59×108元,分别下降了1.85%和1.95%;金属冶炼及压延部门碳排放降至4 997×104 t,下降了12.79%.而我国其他地区2030年P75C65情景下,金属冶炼及压延部门的出口总值、省际输出、本地供应和产出则分别上升了0.05%、2.06%、0.06%和0.06%,分别增至1 283.24×108、28.25×108、26 598.95×108和27 910.43×108元,该部门的碳排放上升了0.05%,增至82 927×104 t.尽管碳减排目标能有效降低广西壮族自治区的碳排放,但也会给其产业部门带来一定的经济损失,该区域的出口、省际输出、本地供应和产出不仅受自身减排目标的影响,也受到我国其他地区减排目标的约束.建议在落实各省(自治区、直辖市)减排任务时,也要实施差异化减排目标,发展当地的优势产业.   相似文献   
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