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121.
地球气候变化既有自然因素又有人为因素,全球变暖主要原因是人类活动温室气体排放过度。因此,在应对气候变化问题上,人们对减排温室气高度重视是理所当然,而长期以来对"适应气候变化"却有所忽视。其实,对发展中国家《适应气候变化》才是当务之急。本文在"发展低碳经济,应对全球变暖"减排二氧化碳温室气体的基础上,论述适应气候变化的迫切性和基本途径。  相似文献   
122.
摘要:对2006~2011年宜良县城NO2、SO2、PM10监测数据进行统计分析,认为SO2是县城的主要污染物。3种污染物年际浓度变化为:NO2、SO2下降趋势显著,PM10下降趋势不显著;季节浓度变化为:S02冬〉秋〉春〉夏,N02、PM10冬〉春〉秋〉夏,并提出防治建议。  相似文献   
123.
冬季黄东海颗粒有机碳的时空分布特征   总被引:1,自引:0,他引:1  
根据2007年1~2月对黄东海大面调查的资料,分析研究了黄东海颗粒有机碳(POC)的时空分布特征。结果表明,冬季黄东海POC的浓度范围是2.49~1 658.96μg/L,平均浓度为125.88μg/L。在垂直方向上,POC由上而下随着水深的增加浓度逐渐降低,到底层后浓度又升高。在平面分布上,POC整体上呈现西部近岸浓度较高、东部离岸浓度较低的特点;POC的高值区集中在浙江近岸海区,特别是浙江舟山群岛南部近海,POC浓度非常高,这是受陆源输入和沉积物再悬浮的共同作用。在周日变化上,受潮汐作用和海区生物活动的影响,东海陆架中部海域除底层以外,其它各层POC在午后、傍晚、凌晨出现浓度的高峰值,而西南海域,除了底层外,其它各层均表现出全日周期变化。  相似文献   
124.
大窑湾海域虾夷扇贝体内麻痹性贝毒的周年变化   总被引:3,自引:3,他引:0  
麻痹性贝毒是对人体健康构成严重危害的甲藻类毒素。2007~2008年,大窑湾虾夷扇贝体内麻痹性贝毒2周年的调查发现,其含量与组分有着明显的季节变化,4-7月份麻痹性贝毒含量较高,4月份最高,平均含量可达378.32μg STXeq/100 g,有C1、C2、GTX1、GTX2、GTX3、GTX5、dcGTX2、dcGTX3、neoSTX、STX等10种毒素组分。大窑湾虾夷扇贝体内麻痹行贝毒组分显著增多,含量明显增高。  相似文献   
125.
突发性环境事件时间序列特征可表征环境风险管理成效及存在问题。研究表明2000年以来中国突发环境事件预防、控制与管理取得了显著成效,其中,突发性水污染事件、大气污染事件以及噪声振动危害年发生频次呈大幅度降低趋势,但固废污染事件自2003年以来的年发生频次变化不大,而其它突发性环境事件自2002年以来的年发生频次则呈快速增长态势,说明中国在强调突发性水环境和大气环境事件监管的同时,还需加强固废污染事件及其它类型突发环境事件的监控与管理。  相似文献   
126.
福建省近10年生态足迹与生态承载力研究   总被引:4,自引:0,他引:4  
利用生态足迹分析法分析了福建省1995年、2000年和2004年的生态足迹及生态承载力.将福建省资源利用的动态特征纳入生态足迹模型中,在此基础上进行横向和纵向比较.结果显示,福建省人均生态赤字从1995年的0.340 3 hm2、2000年的0.443 6 hm2上升到2004年的0.720 2 hm2.这说明福建省在近10年的发展中,生产、生活强度大幅度增加,超过了自然生态系统的承载力,维持现状将难以保证可持续发展.因此,应提高科技与农林业结合水平,大力提倡节约型生活及消费方式,减少生态赤字,遏制生态环境的恶化.  相似文献   
127.
Determinants of adaptive and mitigative capacities (e.g., availability of technological options, and access to economic resources, social capital and human capital) largely overlap. Several factors underlying or related to these determinants are themselves indicators of sustainable development (e.g., per capita income; and various public health, education and research indices). Moreover, climate change could exacerbate existing climate-sensitive hurdles to sustainable development (e.g., hunger, malaria, water shortage, coastal flooding and threats to biodiversity) faced specifically by many developing countries. Based on these commonalities, the paper identifies integrated approaches to formulating strategies and measures to concurrently advance adaptation, mitigation and sustainable development. These approaches range from broadly moving sustainable development forward (by developing and/or nurturing institutions, policies and infrastructure to stimulate economic development, technological change, human and social capital, and reducing specific barriers to sustainable development) to reducing vulnerabilities to urgent climate-sensitive risks that hinder sustainable development and would worsen with climate change. The resulting sustainable economic development would also help reduce birth rates, which could mitigate climate change and reduce the population exposed to climate change and climate-sensitive risks, thereby reducing impacts, and the demand for adaptation. The paper also offers a portfolio of pro-active strategies and measures consistent with the above approaches, including example measures that would simultaneously reduce pressures on biodiversity, hunger, and carbon sinks. Finally it addresses some common misconceptions that could hamper fuller integration of adaptation and mitigation, including the notions that adaptation may be unsuitable for natural systems, and mitigation should necessarily have primacy over adaptation.
Indur M. GoklanyEmail:
  相似文献   
128.
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of watershed development integrating into a suitable mitigation strategy for the country is assessed.
Preety M. BhandariEmail:
  相似文献   
129.
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently. This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions. (1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries. (2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
U. Martin PerssonEmail:
  相似文献   
130.
The coupled SWAP-WOFOST model was used to study the effects of increasing salinity of groundwater, drought and water excess on grass production in The Netherlands. WOFOST simulates crop growth and SWAP simulates transport of water, solutes and heat in the vadose zone. The model was tested using several datasets from field experiments. We applied the models at regional scale where we quantified the impact of various groundwater salinity levels on grass growth and production using historical weather data (1971-2000). The salt concentrations in the subsoil were derived from the National Hydrological Instrument. The results show that salinity effects on grass production are limited. In wet years the excess rainfall will infiltrate the soil and reduce salt water seepage. In a next step we used future weather data for the year 2050, derived from 3 Global Circulation Models. From each model we used data from two CO2 emission scenarios. As expected higher temperatures increased drought stress, however, the production reduction as a result of salt water in the root zone is limited. Salt stress mainly occurred when irrigation was applied with saline water. The increased CO2 concentration in combination with the limited drought stress resulted in increasing simulated actual and potential yields. Overall conclusion for grassland in The Netherlands: drought stress is stronger than stress caused by water excess which on its turn is stronger than salinity stress. Future water demand for irrigation may increase by 11-19% and result in water scarcity if water supply is insufficient.  相似文献   
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