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551.
In Europe, sustainable development (SD) is pursued with not one but two overarching strategies, i.e., the so-called Lisbon and SD strategies. While the Lisbon Strategy is a genuinely European response to global economic and social pressures, SD strategies are national efforts corresponding with international (mainly United Nations) guidance to better coordinate and integrate economic, social and, in particular, environmental policies. The present paper explores the vertical coordination and coherence of the two pan-European strategies. After reviewing the international background of SD strategies and the EU origins of the Lisbon strategy, the paper characterizes and compares the governance architectures of the two strategies. With a solid background on how vertical policy integration functions in the two processes, the paper then shows how this affects the coherence of respective strategy structures and monitoring indicators. Based on an extensive empirical stocktaking study of the objectives and indicators in Lisbon and SD strategies across Europe it is shown that, despite the stronger European coordination through the Open Method of Coordination, the Lisbon process entailed only slightly more coherent national strategies than international guidance did in the context of SD strategies. Thus, the paper concludes that the influence international organizations such as the UN and the OECD have on national policy-making must not be underestimated. 相似文献
552.
A prerequisite for environmental indices is that they represent environmental pressure, and the state of, and impact on environmental conditions. In other words, they should capture as much as possible of the cause-effect chains they represent and relate pressure and effect to criteria of environmental quality. The approach proposed in the article attempts to link the pressure–state–impact–response framework of indicators to the integrated environmental model, based on the method of response function (MRF). The MRF allows to construct purposeful, credible models from data and prior knowledge or information. The data are usually time series observations of system inputs and outputs, and sometimes of internal states. The output of such models is presented with highly aggregated environmental indices, reflecting the main pressure–state–impact–response cause-effect chains. The proposed approach is illustrated with the example of soil erosion indices. 相似文献
553.
Walter G. Whitford Justin Van Zee Maliha S. Nash Walter E. Smith Jeffery E. Herrick 《Environmental monitoring and assessment》1999,54(2):143-171
The relative abundance of ant species was measured by pit-fall trapping at 44 sites in southern New Mexico and southeastern Arizona, U.S.A.. Sites were selected for study based on documentation of a history of disturbance or protection from disturbance, exposure to varying intensities of livestock grazing, dominance by an exotic species of plant and vegetation change resulting from disturbance or restoration efforts. Ant community composition, relative abundances of species, and species richness were the same on disturbed and undisturbed sites. None of the metrics based on hypothesized responses of ants to disturbance clearly distinguished between disturbed and undisturbed sites. Ant communities on sites where restoration efforts have resulted in distinct differences in vegetative cover and composition were similar to the ant communities on degraded unrehabilitated sites on the same soil type. Ant communities in riparian cottonwood gallery forests in Arizona and New Mexico were similar but differed from the assemblages in exotic salt cedar and native ash riparian woodlands. Ant species exhibited remarkable resistance to human-induced disturbances in these rangeland areas. In grasslands dominated by the South African grass, Eragrostis lehmanniana Nees, large seed harvesting ants, Pogonomyrmex spp., were greatly reduced in abundance compared to native grasslands. Other ant metrics were not different in E. lehmanniana grasslands and native grasslands. We conclude that ants cannot be used as indicators of exposure to stress, ecosystem health or of rehabilitation success on rangeland ecosystems. Ants are also not useful indicators of faunal biodiversity in rangeland ecosystems. 相似文献
554.
经0.22μm孔径过滤的太湖梅梁湾水样在UV-B辐射的照射下,有色可溶性有机物(CDOM)吸收和荧光强度明显下降,且与UV-B光源距离、辐射时间及辐射剂量呈正相关关系.拟合结果表明,CDOM吸收系数和荧光值的下降随时间符合一阶动力学方程,距光源5,15,25,35,45cm处时,CDOM吸收系数[a(280)]光化学降解的一阶动力学常数分别为0.0156,0.0116,0.0060,0.0051,0.0029;对应的荧光值Fn(355)的一阶动力学常数分别为0.0256,0.0198,0.0141,0.0102,0.0055.CDOM光化学降解过程中吸收系数与定标后的荧光值存在显著的正相关.实验结果用于野外情况可以推导出太湖表层水体中CDOM在夏季也会发生明显的光化学降解. 相似文献
555.
参与光化学反应的物质对UV能量吸收的估算 总被引:3,自引:0,他引:3
在对北京紫外辐射(UV)观测资料分析的基础上,提出参与光化学反应的物质对UV能量具有吸收作用.计算了1990年12个月实际天气比晴天UV能量的减少值在64~109 W/m2之间,这一减少受臭氧、"水汽"、气溶胶等因子的衰减分别为39.1~66.3,21.5~36.5,3.2~5.5 W/m2(12月除外),12个月的平均值分别为48.3,26.6,4.0 W/m2.计算结果表明,云天大气对UV能量有衰减,其衰减能量中有26.6 W/m2是"水汽的作用",即参与大气光化学反应的物质对UV能量吸收所造成的,此计算值同国外观测与模式的研究结果比较接近.由于现有模式中还没有考虑这一部分能量,所以造成模式结果与观测结果间较大的差异. 相似文献
556.
稀水溶液中Cr(Ⅵ)光化学还原的研究 总被引:5,自引:2,他引:3
研究了稀水溶液中Cr(Ⅵ)的光化学还原过程,考察了·OH自由基俘获剂的种类、结构及溶液pH值对Cr(Ⅵ)还原的影响结果表明稀水溶液中Cr(Ⅵ)的还原过程分化学还原与光化学还原两步进行,前者为直接氧化还原过程,后者则经历自由基反应;·OH自由基俘获剂中羟基的数量和位置对Cr(Ⅵ)的还原均有影响,羟基α位碳上氢原子数量愈多,碳氢键强度愈小,愈有利于Cr(Ⅵ)还原;溶液pH值对Cr(Ⅵ)的还原有重要影响,随着pH值的升高,其还原率和反应速率均下降,当pH≥70时,Cr(Ⅵ)的还原基本停止 相似文献
557.
水溶液中4-氯酚的微波辅助光化学降解 总被引:10,自引:4,他引:6
研究了微波辅助无极紫外灯(MW/UV)光化学降解4-氯酚(4CP)模拟废水;为了考察溶液中4CP的降解效果,用紫外可见分光光度法(UV-VIS)和离子色谱法(IC)测定了溶液中4CP的降解率和Cl-浓度.结果表明,MW/UV体系中30mg/L 4CP反应120min的降解率由紫外(UV)光解体系的21.56%提高到52.40%.提高溶液的pH值、向体系通入氧气、增强光照度以及外加氧化剂H2O2均能增加水溶液中4CP的降解率.微波辅助光化学降解4CP服从一级反应动力学方程. 相似文献
558.
Wetland assessment has been a popular field of research worldwide. However, various indicators have been used in wetland assessment for different purposes and backgrounds and also because of the research limitations. Therefore, a more comprehensive, sound, and efficient indicator system is needed for researchers’ referencing to evaluate wetlands. After an extensive review of wetland assessment literatures, the reported indicators were evaluated using the developed assessment system, based on the Analytical Hierarchy Process (AHP) with three main goals: nature protection, function utilization, and sustainable development. Each indicator was evaluated using two methods. The first method was to study the percentage of the indicator application, and the second was to assess the weighted ratios assigned to the indicators according to principles of comparability, typicality, sensibility, and availability. The results of these two methods were compared to study the commonalities and specialties of the indicators. They also showed that some indicators were widely used, including biodiversity, weather and climate, hydrological change, and the output of wetland. On the other hand, other sustainable indicators were easily ignored, such as environmental carrying capacity and wetland planning. Furthermore, an indicator system for wetland assessment was structured and strategized to discuss how to choose indicators for wetland assessment under different conditions. The proposed approach can be used to guide the process of wetland assessments in the future. 相似文献
559.
水环境质量评价是水资源可持续利用的重要前提,同时也是水环境管理与治理决策的重要依据。为科学评价黄河呼和浩特段水环境质量,基于基础资料数据库,遵循全面性、区域性、易量化性等原则,采用综合污染指数法详细分析了黄河呼和浩特段水环境质量的时空变化情况,进一步揭示了2020年水质季节变化规律,并对主要超标因子进行了深度解析。结果表明:随着一系列环境保护政策和管理措施的实施,2015—2020年黄河呼和浩特段水环境质量综合指数下降了75.87%。在时间尺度上,各断面的水环境质量综合指数平均值由2015年的93.81下降至2020年的22.64,整体水环境质量评价等级由G4转为G2,对应的水环境质量状况由中度污染转为较好;在空间尺度上,上游水环境质量优于下游,城区段水环境质量较差。此外,评价结果显示,部分水体当前仍存在氨氮超标问题。评价结果较为客观地反映了黄河呼和浩特段的水环境质量,可为水环境管理提供决策依据。 相似文献
560.
Shear H 《Environmental monitoring and assessment》2006,113(1-3):199-225
Since 1972, the Parties (United States and Canada, 1987) to the Great Lakes Water Quality Agreement have been working collaboratively to achieve the purpose of the Agreement “to restore and maintain the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem”. Billions of dollars and countless person – hours have been expended towards this end, but have the Parties, and their numerous collaborators at the state, provincial, and municipal levels, along with industry and citizen activists achieved meaningful results? This paper will examine the information provided through various monitoring programs and will assess the success of the Parties' programs, and will also discuss the continuing threats to achieving the purpose of the Agreement. 相似文献