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71.
72.
结合江苏省“十一五”期间环境质量状况及变化情况,综合分析了环境空气、水环境、声环境质量及污染物排放状况.“十一五”期间,江苏省经济总量以13.5%的平均速度增长,社会、经济的快速发展给全省环境质量带来巨大的胁迫压力,资源能源消耗迅速攀升,“三废”产生总量持续增长;而由于加大了节能减排和环境治理投入力度,采取了一系列措施... 相似文献
73.
Since the United Nations Conference on Environment and Development (UNCED) [1992, Agenda 21: programme of action for sustainable development. United Nations Conference on Environment and Development (UNCED), 3-14 June 1992. Rio de Janeiro, Brazil, 294pp.], the management of information has become central to the management of forest resources. In the cases of North America and Europe, similar issues have been challenging policy makers as they determine the information suitable for monitoring progress towards sustainable forest management (SFM). Using an 'online' survey, this research explored multiple stakeholder perspectives on monitoring and information reporting for SFM in different jurisdictions. The research was based on the premise that an analysis of the variation in stakeholder observations across a range of SFM 'issue areas' could provide valuable insight into the perceived need for SFM-related monitoring and information reporting in the regions of Europe, Canada and the USA. Despite the traditional limitations associated with exploratory survey research, the results indicate a demand for more information on SFM-related issues. The results also highlight the degree to which the perceptions of a sample of stakeholders can differ between Europe, USA and Canada. While these results cannot be generalized beyond the present study, they do suggest that further studies are needed to understand stakeholder perspectives on forestry-related monitoring and information reporting in different jurisdictions. 相似文献
74.
This report summarizes the results of two studies of electricity supply for Europe (EU), the Middle East (ME) and North Africa
(NA) up to the year 2050. It shows that a transition to competitive, secure and sustainable supply of electricity and water
is possible using renewable energy sources, efficiency gains and fossil fuel backup for balancing power. A strong cooperation
between the EU and MENA for the market introduction of renewable energy and the interconnection of the electricity grids by
high-voltage direct-current transmission are keys to the success and survival of the whole region. However, the necessary
measures will take at least two decades to become effective. Therefore, adequate policy and economic frameworks for their
realization must be introduced immediately. The importance of sustainable energy for the security of freshwater supplies in
MENA is also described.
相似文献
Hans Müller-SteinhagenEmail: |
75.
针对快速城镇化区域产业快速发展、人口高度密集与排水设施建设滞后间的突出矛盾,以苏州官渎里区域的典型重污染河道——官渎花园内河为研究对象,在分析区域排污特征的基础上,系统总结点污染源、面污染源和内污染源在该类区域的具体表现形式和影响因素,对各类污染物入河量进行调查测算.根据测算结果,官渎花园内河的CODcr、NH3-N、TN和TP年入河量分别为222.54、11.16、16.63和2.56t·a-1.对各污染源贡献率的分析结果表明,工业污染和生活污染为主要污染源,其次为降雨径流污染.在上述测算分析的基础上,结合苏南快速城镇化区域发展特点,提出了若干河道污染控制的对策与建议. 相似文献
76.
20世纪90年代以来,区域差异研究成为学术界和政府管理者关注的热点领域。长期以来学者们主要以单一经济指标或复合经济指标作为衡量因子,分析区域经济差异时空演变及差异背后的自然、社会、经济驱动机理。从可持续发展的角度看,区域发展不单是区域经济的发展,而应是社会、经济与资源环境三方面的协调。基于这一理解,从可持续协调发展入手,建立了区域发展综合评价指标体系,选取了表征社会进步、经济发展和资源环境支持3个方面的27个因素作为评价指标,分析了区域综合发展的测算方法,提出了综合发展指数和发展协调指数。在案例分析中运用所设计的测度方法对江苏省内县级行政单位的综合发展进行了评价和分析。 相似文献
77.
杨英 《长江流域资源与环境》2008,17(2):212-212
为了解不同植被类型土壤水资源的变化规律,选择南水北调中线水源区宁陕县寨沟区域典型植被针阔混交林、针叶林、板栗林、灌木林、荒坡草地和坡耕地为研究对象,通过样地调查与实验分析的方法对其土壤水分物理特征及有机质含量进行测定研究。结果表明,各种有林地的土壤容重、孔隙度和有机质等理化特征均优于荒坡和坡耕地;针阔混交林土壤含水量最高,蓄水能力明显好于其它植被类型;在垂直剖面上,各种植被类型坡地土壤含水量和饱和蓄水量随土壤深度的增加基本呈递减趋势,但有林地下降幅度较大,表层含水量明显高于荒坡与坡耕地表层。由此可见,在涵养水源方面,针阔混交林最好,针叶林、板栗林与灌木林次之,荒坡与坡耕地较差。 相似文献
78.
Characteristics and recent trends of sulfur dioxide at urban, rural, and background sites in North China: Effectiveness of control measures 总被引:4,自引:0,他引:4
SO2 measurements made in recent years at sites in Beijing and its surrounding areas are performed to study the variations and trends of surface SO2 at different types of sites in Northern China. The overall average concentrations of SO2 are (16.8 ± 13.1) ppb, (14.8 ± 9.4) ppb, and (7.5 ± 4.0) ppb at China Meteorological Administration (CMA, Beijing urban area), Gucheng (GCH, relatively polluted rural area, 110 km to the southwest of Beijing urban area), and Shangdianzi (SDZ, clean background area, 100 km to the northeast of Beijing urban area), respectively. The SO2 levels in winter (heating season) are 4-6 folds higher than those in summer. There are highly significant correlations among the daily means of SO2 at different sites, indicating regional characteristics of SO2 pollution. Diurnal patterns of surface SO2 at all sites have a common feature with a daytime peak, which is probably caused by the downward mixing and/or the advection transport of SO2-richer air over the North China Plain. The concentrations of SO2 at CMA and GCH show highly significant downward trends (-4.4 ppb/yr for CMA and -2.4 ppb/yr for GCH), while a less significant trend (-0.3 ppb/yr) is identified in the data from SDZ, reflecting the character of SDZ as a regional atmospheric background site in North China. The SO2 concentrations of all three sites show a significant decrease from period before to after the control measures for the 2008 Olympic Games, suggesting that the SO2 pollution control has long-term effectiveness and benefits. In the post-Olympics period, the mean concentrations of SO2 at CMA, GCH, and SDZ are (14.3 ± 11.0) ppb, (12.1 ± 7.7) ppb, and (7.5 ± 4.0) ppb, respectively, with reductions of 26%, 36%, and 13%, respectively, compared to the levels before. Detailed analysis shows that the differences of temperature, relative humidity, wind speed, and wind direction were not the dominant factors for the significant differences of SO2 between the pre-Olympics and post-Olympics periods. By extracting the data being more representative of local or regional characteristics, a reduction of up to 40% for SO2 in polluted areas and a reduction of 20% for regional SO2 are obtained for the effect of control measures implemented for the Olympic Games. 相似文献
79.
1995-2015年江苏省土地利用功能转型特征及其协调性分析 总被引:13,自引:3,他引:10
土地利用功能转型可实现土地利用功能协调,是实施区域可持续发展的重要路径。从功能协调角度构建土地利用功能转型分析框架,利用江苏省1995年、2000年、2005年、2010年和2015年5期遥感影像及相关资源利用和社会经济数据,构建三级土地利用功能评价体系,以县域为评价单元,通过三角模型和空间相关分析等方法,定量解析江苏省土地利用功能时空演变特征及其与土地可持续利用目标的协调状况。研究结果显示:(1)研究期内,江苏省土地利用功能总水平提升减慢,其中生产、生活功能不同程度提升,生态功能明显下降。(2)生产、生活功能空间集聚不突出,生态功能的热点、冷点区域呈“Y”型集聚分布。(3)不同功能区功能协调性态势不一,重点开发区和限制开发区可持续发展态势总体良好,优化开发区可持续发展程度较弱并持续恶化。建议江苏省在落实发展蓝图和空间规划的过程中,应优先推进苏南现代化示范区建设,重点实施重点开发区生活功能转型、Ⅰ类限制开发区生产功能转型策略,并严格落实禁止开发区的生态保护责任等差别化管理策略。 相似文献
80.
为探明北运河流域(北京段)多层沉积物中PAHs(多环芳烃)的污染状况,利用活塞式底泥取样器于2014年11月采集了9处沉积物样品,取样深度为30~80 cm,每处样品根据其垂向介质特征大致分成3~4层,分别测定各层样品的粒径、TOM(总有机质)及16种PAHs的质量分数,探讨PAHs在河道沿程与垂向上的分布特征、来源及生态风险评价.结果表明,北运河流域(北京段)沉积物以砂质壤土为主,w(TOM)(以干质量计,下同)为103.4~146.8 g/kg,w(∑16PAHs)为598.1~28 730.6 ng/g,各层w(∑16PAHs)为108.5~8 810.8 ng/g.沉积物中PAHs以高环为主,主要包括有Phe(Phenanthrene,菲)、Fla(Fluoranthene,荧蒽)、Pyr(Pyrene,芘)、BbF〔Benzo(b)fluoranthene,苯并[b]荧蒽〕.在河道沿程变化上,中下游沉积物的污染程度远高于上游.在垂向变化上,w(TOM)和沉积物粒径对PAHs的分布影响有限,PAHs的垂向分布主要受所处沉积环境与历史污染程度影响.根据主成分分析与同分异构体比值法推断,PAHs主要来源于化石燃料与生物燃料的燃烧,少部分为石油源.利用效应区间值得出的生态风险评价结果表明,北运河流域(北京段)沉积物中PAHs可能已对环境产生负面影响,其中BbF、BkF、InP与BgP已对环境产生毒副作用,需要给予关注与解决. 相似文献