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611.
This article will briefly outline the origins, structure and functions of United Nations Environment Program and the Commission on Sustainable Development in the context of the goals of ecologically sustainable development (ESD). Economic development, social development and environmental protection form the three interconnected parts of ESD. The achievements of the key UN environmental institutions and programs in opening up the global system to civil society, the private sector and a diversity of actors and interests, promoting the role of poverty alleviation as part of ESD through the Millennium Development Goals, and facilitating important Multilateral Environmental Agreements should be recognized. However, with these notable exceptions, organizations such as United Nations Environment Program and the Commission on Sustainable Development have become weak in scientific and technical leadership, global policy, co-ordination (inside and outside the UN) and has few achievements in the inter- national and national implementation of obligations and standards in Global Environmental Governance - including enforcement, compliance and effectiveness. This article will outline the key reasons for this inadequacy. Attention will also be focused on the way forward through of a new United Nations Environment Organization. This will require a clarification of purpose and function (within the UN system and as part of global governance structures) as well as consideration of whether it depends on system-wide UN reform. It is recommended that medium and long term strategies for reform are necessary.  相似文献   
612.
Abstract: Accurate and reliable evapotranspiration (ET) datasets are crucial in regional water and energy balance studies. Due to the complex instrumentation requirements, actual ET values are generally estimated from reference ET values by adjustment factors using coefficients for water stress and vegetation conditions, commonly referred to as crop coefficients. Until recently, the modeling of reference ET has been solely based on important weather variables collected from weather stations that are generally located in selected agro‐climatic locations. Since 2001, the National Oceanic and Atmospheric Administration’s Global Data Assimilation System (GDAS) has been producing six‐hourly climate parameter datasets that are used to calculate daily reference ET for the whole globe at 1‐degree spatial resolution. The U.S. Geological Survey Center for Earth Resources Observation and Science has been producing daily reference ET (ETo) since 2001, and it has been used on a variety of operational hydrological models for drought and streamflow monitoring all over the world. With the increasing availability of local station‐based reference ET estimates, we evaluated the GDAS‐based reference ET estimates using data from the California Irrigation Management Information System (CIMIS). Daily CIMIS reference ET estimates from 85 stations were compared with GDAS‐based reference ET at different spatial and temporal scales using five‐year daily data from 2002 through 2006. Despite the large difference in spatial scale (point vs. ~100 km grid cell) between the two datasets, the correlations between station‐based ET and GDAS‐ET were very high, exceeding 0.97 on a daily basis to more than 0.99 on time scales of more than 10 days. Both the temporal and spatial correspondences in trend/pattern and magnitudes between the two datasets were satisfactory, suggesting the reliability of using GDAS parameter‐based reference ET for regional water and energy balance studies in many parts of the world. While the study revealed the potential of GDAS ETo for large‐scale hydrological applications, site‐specific use of GDAS ETo in complex hydro‐climatic regions such as coastal areas and rugged terrain may require the application of bias correction and/or disaggregation of the GDAS ETo using downscaling techniques.  相似文献   
613.
在环境治理的问题上,20世纪人类社会所表现出来的是一种对契约、技术与制度的崇尚,反映了近代以来社会治理中的价值中立与道德祛魅精神。然而,随着环境危机事件的频发,特别是在环境以及生态问题构成了风险社会的一个重要维度的情况下,依靠契约、制度、技术的环境治理方案陷入低效甚至失灵的境地。人类命运共同体理念的提出,开拓了环境治理的新思路,让我们看到构建人与人、人与自然生命共同体的环境合作治理模式建立的希望。环境合作治理是一种可以将所有力量整合到合作行动体系中的治理模式,能够有效应对日趋恶化的环境问题,并将人类的生存与发展建立在环境友好的基础上。只有当环境治理采用了合作模式,才能在环境的维度上增强人类命运共同体的现实性。  相似文献   
614.
Linking GIS-based models to value ecosystem services in an Alpine region   总被引:11,自引:1,他引:11  
Planning frequently fails to include the valuation of public goods and services. This can have long-term negative economic consequences for a region. This is especially the case in mountainous regions such as the Alps, which depend on tourism and where land-use changes can negatively impact key ecosystem services and hence the economy. In this study, we develop a semi-automatic procedure to value ecosystem goods and services. Several existing process-based models linked to economic valuation methods are integrated into a geographic information system (GIS) platform. The model requires the input of a digital elevation model, a land-cover map, and a spatially explicit temperature dataset. These datasets are available for most regions in Europe. We illustrate the approach by valuing four ecosystem services: avalanche protection, timber production, scenic beauty, and habitat, which are supplied by the “Landschaft Davos”, an administrative district in the Swiss Alps. We compare the impacts of a human development scenario and a climate scenario on the value of these ecosystem services. Urban expansion and tourist infrastructure developments have a negative impact on scenic beauty and habitats. These impacts outweigh the benefits of the developments in the long-term. Forest expansion, predictable under a climate change scenario, favours natural avalanche protection and habitats. In general, such non-marketed benefits provided by the case-study region more than compensate for the costs of forest maintenance. Finally, we discuss the advantages and disadvantages of the approach. Despite its limitations, we show how this approach could well help decision-makers balance the impacts of different planning options on the economic accounting of a region, and guide them in selecting sustainable and economically feasible development strategies.  相似文献   
615.
To study how global warming and eutrophication a ect water ecosystems, a multiplicative growth Monod model, modified by incorporating the Arrhenius equation, was applied to Lake Taihu to quantitatively study the relationships between algal biomass and both nutrients and temperature using long-term data. To qualitatively assess which factor was a limitation of the improved model, temperature variables were calculated using annual mean air temperature (AT), water temperature (WT), and their average temperature (ST), while substrate variables were calculated using annual mean total nitrogen (TN), total phosphorus (TP), and their weighted aggregate (R), respectively. The nine fitted curves showed that TN and AT were two important factors influencing algal growth; AT limited growth as algal photosynthesis is mainly carried out near the water surface; N leakage of phytoplankton and internal phosphorus load from sediment explains why TN was the best predictor of peak biomass using the Monod model. The fitted results suggest that annual mean algal biomass increased by 0.145 times when annual mean AT increased by 1.0°C. Results also showed that the more eutrophic the lake, the greater the e ect AT had on algal growth. Subsequently, the long-term joint e ect of annual temperature increase and eutrophication to water ecosystems can be quantitatively assessed and predicted.  相似文献   
616.
2003~2014年东北三省气溶胶光学厚度变化分析   总被引:4,自引:5,他引:4  
利用2003~2014年MODIS-Aqua气溶胶光学厚度(AOD)产品、DMSP卫星夜间灯光时间资料和基本气象资料,分析我国东北三省(辽宁、吉林、黑龙江)大气气溶胶光学厚度年际变化及季节变化的空间分布特征.结果表明,东北三省多年平均AOD空间分布存在由大连、沈阳、长春和哈尔滨等城市构成的一个高值带,呈东北-西南走向,多年平均AOD值为0.4~0.8;东北三省植被覆盖率较高的东部和北部是AOD的低值区,多年平均AOD小于0.3;东北三省AOD季节变化为AOD春季到夏季升高,秋季下降,冬季再次升高.东北三省AOD年际变化特征为大部分低值地区呈减小趋势,但以沈阳、长春和哈尔滨为轴线的东北-西南走向的高值区域呈增大趋势,反映了近10多年出现的空气质量两极分化趋势.此外研究了东北三省年均AOD在强、弱西北太平洋夏季风年时的空间分布差异,受地面风场影响,AOD在强季风年时较弱季风年偏低.  相似文献   
617.
全球气候变化与21世纪我国能源发展战略   总被引:1,自引:0,他引:1  
分析了全球气候变化特点及对我国的挑战,提出21世纪我国能源发展战略。  相似文献   
618.
土壤氨氧化微生物是草地生态系统氮循环过程特别是氨氧化过程的主要驱动者,对全球变化具有响应、适应和反馈机制.通过采集在内蒙古温带草原设置的长期增温增雨野外控制实验的土壤样品,应用定量PCR、限制性末端片段长度多态性(terminal restriction fragment length polymorphism,T-RFLP)和克隆文库等方法研究氨氧化古菌和细菌的丰度、多样性和群落结构对增温增雨的响应.结果表明,增雨显著升高了土壤pH,而增温显著降低了土壤呼吸.氨氧化微生物丰度在各处理之间没有显著差异.T-RFLP结果表明,增雨显著影响土壤氨氧化细菌的群落结构,增温和增雨对土壤氨氧化微生物群落结构的交互作用并不显著.结构方程模型的结果显示植物多样性与氨氧化古菌和细菌的群落结构有显著的相关关系,表明气候变化-微生物-植物三者之间存在着一定的关系.研究结果预示土壤微生物对长期气候变化有一定的适应能力,这对预测未来生态系统的变化具有重要的参考价值.  相似文献   
619.
吉林省城市土地集约利用的空间分异   总被引:7,自引:1,他引:7  
何为  修春亮 《自然资源学报》2011,26(8):1287-1296
以吉林省9个地级市市区为研究对象,从土地投入强度、利用程度、利用效益和生态环境集约度四个方面构建城市土地集约利用度评价的指标体系。采用SPSS 13.0的全局主成分分析法和聚类分析方法对所属9个地级市2000-2009年的土地集约利用度进行综合评价,并分析其空间分异特征。结果表明:2000-2009年吉林省城市土地集约利用度提高,在空间上呈现为较强的极核效应,同时存在明显的东、中、西差异,10 a间省内城市土地集约利用度总体差异呈现波动性缩小趋势。并从产业结构、区域发展基础、经济发展水平、城市规模等方面分析了差异产生的原因,得出:影响吉林省各地级市土地集约利用的因素是复杂的,区域自然条件和地理环境差异只是基底条件,经济发展差异对土地集约利用分异作用较大。  相似文献   
620.
冬水田转稻麦轮作对小麦生长季温室气体排放的影响   总被引:5,自引:0,他引:5  
用静态暗箱-气相色谱法测定了川中丘陵地区典型冬水田(RF)及冬水田转稻麦轮作处理(RW)在小麦生长季的温室气体排放通量,并同步测定了土壤温度、水分和可溶态碳氮含量.结果表明,RW在小麦生长季的CH4、生态系统呼吸CO2和N2O平均排放通量分别为0.05、117.01 mg·m-2·h-1(以C计)和77.19μg·m-2·h-1(以N计),而RF相应通量分别为1.43、7.85 mg·m-2·h-1和-0.61μg·m-2·h-1.RW施氮肥后出现N2O的排放峰,其N2O直接排放系数为1.28%.土壤可溶态有机碳含量与CO2通量之间呈显著正相关关系(r=0.342,p0.01),与CH4、N2O的相关关系不显著;硝态氮、可溶态总氮含量与N2O通量的关系为显著正相关,但与CH4通量呈显著负相关.RF的综合增温潜势(以CO2-eq计,下同)为3.03 Mg·hm-2,大于RW(-1.66 Mg·hm-2),暗示冬水田转稻麦轮作会降低生态系统的综合增温效应.  相似文献   
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