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1.
This paper attempts to examine whether information from valuation studies can help the design of policies adequate to reverse and halt the generally poor state of marine and coastal ecosystems of the Mediterranean and the Black Sea. Economic implications of managing coastal and marine environments are thus discussed by assessing the results of different valuation studies implemented in the area. Lessons and policy recommendations from existing literature are inferred to guide marine resources management decisions. One of our main findings is that there are extremely few published studies within the Mediterranean and Black Sea region which highlights the potential for future research on coastal and marine ecosystems ability to sustain different goods and services as a result of climate change and anthropogenic drivers in the area. However, results reveal that there are substantial positive economic values attached to marketed and non-marketed services provided by marine and coastal ecosystems that justify their sustainable use and management.  相似文献   

2.
青藏高原东北部气候变化的异质性及其成因   总被引:1,自引:1,他引:1  
利用1961-2016年西宁等青藏高原东北部13个气象台站气温、降水等气象资料以及国家气候中心发布的南海季风指数、西伯利亚高压指数等大气环流特征量数据,分析近56年来气候变化与高原主体的差异性及其可能的气候成因。研究表明:近56年来青藏高原东北部气候变暖趋势十分显著,年平均气温气候倾向率高达0.39 ℃/10 a,呈现出三次明显的阶梯性增高态势,并于1994年前后发生了由冷到暖的突变,同时具有明显的空间差异性;年降水量及四季降水量均没有明显变化趋势,虽然经历了2002年左右由少到多的变化,但并未出现明显突变,年降水量具有3年、5年的准周期,而年降水日数微弱减少,降水强度呈增加趋势;该区域气候变化的年际波动主要受到东亚季风、高原季风和南海季风的年际振荡及其相互作用的影响,而西风环流的作用并不明显,植被覆盖的恢复既是对2002年以来降水量增加的具体反应,同时也对于气候变暖趋势起到了一定的缓和作用。  相似文献   

3.
Phenological shifts are widely reported for different species as a response to climate change. Still, the efficiency of this mechanism is questioned because of the accelerated rate of change and the different change patterns of various climate parameters that may cause mismatches. Here, using loggerhead sea turtles (Caretta caretta) as model species, we examined whether phenological shifts could be an effective adaptive strategy over the critical period that determines reproductive output in the Mediterranean region. We compared the rate of temperature and precipitation change over the recent past (1971–2015) and future periods (2016–2060) along the 45 main nesting sites of the Mediterranean population, during the incubation period. Next, utilizing predictions of an earlier nesting season, we evaluated whether the timing of incubation will impact offspring survival on the Mediterranean population. To further assess species vulnerability, we investigated any potential relationship between hatching success and climate parameters at the largest Mediterranean nesting rookery (Zakynthos, Greece). We found that phenological changes would allow species to capture a thermal window similar to one they experience nowadays during the incubation period. Still, phenological shifts might be less adequate to follow precipitation changes, which however, were found to have a limited impact upon hatching success. Global adaptation management strategies should be directed towards (a) acquisition of long-term high-resolution temperature and precipitation series at nesting sites, (b) developing early warning systems to prevent negative impacts upon reproductive outputs, and (c) directly applying cooling of the nests when first altered climate signs are detected.  相似文献   

4.
Current trends in Mediterranean agriculture reveal differences between the Northern and Southern Mediterranean countries as related to population growth, land and water use, and food supply and demand. The changes in temperature and precipitation predicted by general circulation models for the Mediterranean region will affect water availability and resource management, critically shaping the patterns of future crop production. Three companion papers analyze in detail future impacts of predicted climate change on wheat (Triticum aestivum L.) and maize (Zea mays L.) production in Spain, Greece, and Egypt, and test farm- level adaptation strategies such as early planting and cultivar change with the aid of dynamic crop models. Strategies to improve the assessment of the potential effects of future climate change on agricultural production are discussed.  相似文献   

5.
Water is scarce in Mediterranean countries: cities are crowded with increasing demand; food is produced with large amounts of water; ecosystems demand more water that is often available; drought affects all. As climate change impacts become more noticeable and costlier, some current water management strategies will not be useful. According to the findings of CIRCE, the areas with limited water resources will increase in the coming decades with major consequences for the way we produce food and we protect ecosystems. Based on these projections this paper discusses water policy priorities for climate change adaptation in the Mediterranean. We first summarise the main challenges to water resources in Mediterranean countries and outline the risks and opportunities for water under climate change based on previous studies. Recognising the difficulty to go from precipitation to water policy, we then present a framework to evaluate water availability in response to natural and management conditions, with an example of application in the Ebro basin that exemplifies other Mediterranean areas. Then we evaluate adaptive capacity to understand the ability of Mediterranean countries to face, respond and recover from climate change impacts on water resources. Social and economic factors are key drivers of inequality in the adaptive capacity across the region. Based on the assessment of impacts and adaptive capacity we suggest thresholds for water policy to respond to climate change and link water scarcity indicators to relevant potential adaptation strategies. Our results suggest the need to further prioritise socially and economically sensitive policies.  相似文献   

6.
地球系统模式CESM模拟的ENSO变率与中国东部降水格局   总被引:1,自引:0,他引:1  
根据地球系统模式(CESM)的千年控制模拟试验结果,以Niño3.4区的逐月海表温度变化为指标,辨识了212次El Niño事件、226次La Niña事件;分析了El Niño和La Niña事件发生当年及次年中国东部5-9月降水异常的空间格局;探讨了ENSO与华北、江淮、江南和华南4个区域旱涝的关系。结果表明:El Niño事件发生的当年5-9月,华北和华南地区降水减少2%~10%,长江中下游地区降水略有增加(0~2%);次年,江南地区转为降水增加(2%~10%),华北北部降水继续减少。在La Niña事件发生的当年,华北地区降水偏多(增加2%~10%);次年,江淮地区降水显著减少(2%~5%)。ENSO增强会导致降水变幅加大。在El Niño衰减并向La Niña快速发展的年份,江南地区出现洪涝灾害的概率较其他年份高1倍以上。这些认识为深入揭示气候系统内部年际变率对中国东部降水格局变化与区域旱涝的影响作用、理解2016年长江中下游发生重大洪涝灾害提供了异常天气气候背景依据。  相似文献   

7.
区域气象条件和减排对空气质量改善的贡献评估   总被引:6,自引:6,他引:0  
武文琪  张凯山 《环境科学》2021,42(2):523-533
区域气象条件和减排与空气质量的变化关系密切.区域污染天气的发生不只受人为排放的影响,其与气象条件也密切有关.我国地处全球的主要季风气候区,大气环流具有明显的季风气候变化特征,区域气象条件受年际气候变化影响显著.研究通过分析不同气候条件下京津冀地区、成渝地区、长三角和珠三角城市群2001~2018年主要气象要素及其污染天气的变化趋势,利用KNN大数据挖掘算法量化分析区域气象条件和减排对大气污染的贡献率.结果表明,2001~2018年间全球气候变化异常频繁,厄尔尼诺/拉尼娜非正常气候占比近一半.减排与气候变化均对空气质量的改善起促进作用.在非正常气候条件下,气象对空气质量改善的贡献更为明显.例如,非正常气候时京津冀地区气象条件对空气质量改善的贡献约为51%,而正常气候时约为30%.对于长三角和珠三角城市群,其气象条件在非正常气候时的贡献达到了50%左右,几乎与减排贡献相当.此外,各区域2015~2018年的减排贡献均高于2001~2012年的平均水平,表明随着我国实施大气污染物排放控制措施力度的增大,减排对空气质量改善的贡献显著.但气象条件对空气质量改善的贡献仍不容忽视,区域减排控制仍然任重而道远.  相似文献   

8.
Northern Tibet is the headstream region for the Yangtze, Salween River, Mekong River, and numerous other inflowing rivers and high mountain lakes. Sustaining the environmental conditions in the region is of vital importance for Tibet and the whole of China. The alpine grassland ecosystem in Northern Tibet is the most important ecosystem and extremely sensitive to climate change and human activity. In this study, we analyzed the characteristics of climate variability based on observed meteorological data and future climate scenarios, and reviewed the impact of climate variability and to explore adaptation strategies of alpine grassland in Northern Tibet. The result showed that the annual mean temperature has increased by 0.31 °C·10a?1 while the annual total precipitation has increased by 14.6 mm·10a?1 with high inter-annual and inter-seasonal fluctuations in Northern Tibet from 1961 to 2008. The rising trends of temperature and precipitation would be continued and the aridity indices showed a decreasing trend in the future, which potentially predicts that the climate in Northern Tibet becomes warmer and dryer. The climate variability results the melting of glaciers, the expansion of inland high mountain lakes and the negative impacts on alpine grassland in recent years. In order to adapt to such possible future climate changes, the alpine grassland water-saving irrigation was recommended as key adaptation measure and also rational grazing management, alpine grassland fencing and artificial grass planting were selected as adaptation measures, to lower the negative impacts of climate variability on the alpine grassland ecosystem in Northern Tibet.  相似文献   

9.
Meeting the growing demand for food in the future will require adaptation of water and land management to future conditions. We studied the extent of different adaptation options to future global change in the Mediterranean region, under scenarios of water use and availability. We focused on the most significant adaptation options for semiarid regions: implementing irrigation, changes to cropland intensity, and diversification of cropland activities. We used Conversion of Land Use on Mondial Scale (CLUMondo), a global land system model, to simulate future change to land use and land cover, and land management. To take into account future global change, we followed global outlooks for future population and climate change, and crop and livestock demand. The results indicate that the level of irrigation efficiency improvement is an important determinant of potential changes in the intensity of rain-fed land systems. No or low irrigation efficiency improvements lead to a reduction in irrigated areas, accompanied with intensification and expansion of rain-fed cropping systems. When reducing water withdrawal, total crop production in intensive rain-fed systems would need to increase significantly: by 130% without improving the irrigation efficiency in irrigated systems and by 53% under conditions of the highest possible efficiency improvement. In all scenarios, traditional Mediterranean multifunctional land systems continue to play a significant role in food production, especially in hosting livestock. Our results indicate that significant improvements to irrigation efficiency with simultaneous increase in cropland productivity are needed to satisfy future demands for food in the region. The approach can be transferred to other similar regions with strong resource limitations in terms of land and water.  相似文献   

10.
Climate change, involving changes in mean climate and climatic variability, is expected to severely affect agriculture and there is a need to assess its impact in order to define the appropriate adaptation strategies to cope with. In this paper, we projected a scenario of European agriculture in a +2°C (above pre-industrial levels) world in order to assess the potential effect of climatic change and variability and to test the effectiveness of different adaptation options. For this purpose, the outputs of HadCM3 General Circulation Model (GCM) were empirically downscaled for current climate (1975–2005) and a future period (2030–2060), to feed a process-based crop simulation model, in order to quantify the impact of a changing climate on agriculture emphasising the impact due to changes in the frequency of extreme events (heat waves and drought). The same climatic dataset was used to compare the effectiveness of different adaptations to a warmer climate strategies including advanced or delayed sowing time, shorter or longer cycle cultivar and irrigation. The results indicated that both changes in mean climate and climate variability affected crop growth resulting in different crop fitting capacity to cope with climate change. This capacity mainly depended on the crop type and the geographical area across Europe. A +2°C scenario had a higher impact on crops cultivated over the Mediterranean basin than on those cultivated in central and northern Europe as a consequence of drier and hotter conditions. In contrast, crops cultivated in Northern Europe generally exhibited higher than current yields, as a consequence of wetter conditions, and temperatures closer to the optimum growing conditions. Simple, no-cost adaptation options such as advancement of sowing dates or the use of longer cycle varieties may be implemented to tackle the expected yield loss in southern Europe as well as to exploit possible advantages in northern regions.  相似文献   

11.
A latest Cretaceous (68 to 65 million years ago) vertebrate microfossil assemblage discovered at Kakanaut in northeastern Russia reveals that dinosaurs were still highly diversified in Arctic regions just before the Cretaceous–Tertiary mass extinction event. Dinosaur eggshell fragments, belonging to hadrosaurids and non-avian theropods, indicate that at least several latest Cretaceous dinosaur taxa could reproduce in polar region and were probably year-round residents of high latitudes. Palaeobotanical data suggest that these polar dinosaurs lived in a temperate climate (mean annual temperature about 10°C), but the climate was apparently too cold for amphibians and ectothermic reptiles. The high diversity of Late Maastrichtian dinosaurs in high latitudes, where ectotherms are absent, strongly questions hypotheses according to which dinosaur extinction was a result of temperature decline, caused or not by the Chicxulub impact.  相似文献   

12.
The FLASH project was implemented from 2006 to 2010 under the EU FP6 framework. The project focused on using lightning observations to better understand and predict convective storms that result in flash floods. As part of the project 23 case studies of flash floods in the Mediterranean region were examined. For the analysis of these storms lightning data from the ZEUS network were used together with satellite derived rainfall estimates in order to understand the storm development and electrification. In addition, these case studies were simulated using mesoscale meteorological models to better understand the meteorological and synoptic conditions leading up to these intense storms. As part of this project tools for short term predictions (nowcasts) of intense convection across the Mediterranean and Europe, and long term forecasts (a few days) of the likelihood of intense convection were developed. The project also focused on educational outreach through our website http://flashproject.org supplying real time lightning observations, real time experimental nowcasts, forecasts and educational materials. While flash floods and intense thunderstorms cannot be prevented as the climate changes, long-range regional lightning networks can supply valuable data, in real time, for warning end-users and stakeholders of imminent intense rainfall and possible flash floods.  相似文献   

13.
In the Southern Mediterranean region hilly and remote areas are afflicted with the high cost of diesel fuel, problematic supply, poor or non-existent grid connections and lack of maintenance technicians to service farm grid generation systems and machinery. A prototype Battery Powered Electric Vehicle (BPEV) charged using a solar photovoltaic array (10 kWp) was installed at a monastery situated at Achkout (Lebanon) with a total agricultural area of 50 ha, 10 ha of which was devoted to viticulture. The purpose of this was to investigate the potential for the cleaner production of power hence reducing the use of diesel fuels in agriculture. Data collected from the test site is presented and used to validate a numerical model. The numerical model was then used to extend the study further to the other countries bordering the Mediterranean Sea which have different levels of solar irradiance. Currently the average cost of diesel fuel within the EU is at an all-time high of 1.32 €/L. A life cycle costing determined that if the current trends in inflation in the EU continue and that fuel costs increase by 7.5% per annum, then battery powered electric vehicles charged using solar photovoltaics are economically viable in areas of high solar irradiance. The numerical model was then used to determine the outcome of using lithium titanate batteries instead of conventional lead-acid batteries. Adoption of the described system for a 10 ha vineyard would result in annual fuel saving of 4200–5200 L of diesel depending on which location in the Mediterranean area a system such as this is installed.  相似文献   

14.
The Mediterranean and neighboring countries are already experiencing a broad range of natural and man-made threats to water security. According to climate projections, the region is at risk due to its pronounced susceptibility to changes in the hydrological budget and extremes. Such changes are expected to have strong impacts on the management of water resources and on key strategic sectors of regional economies. Related developments have an increased capacity to exacerbate tensions, and even intra- and inter-state conflict among social, political, ecological and economic actors. Thus, effective adaptation and prevention policy measures call for multi-disciplinary analysis and action.This review paper presents the current state-of-the-art on research related to climate change impacts upon water resources and security from an ecological, economic and social angle. It provides perspectives for current and upcoming research needs and describes the challenges and potential of integrating and clustering multi-disciplinary research interests in complex and interwoven human-environment systems and its contribution to the upcoming 5th assessment report of the IPCC.  相似文献   

15.
利用1982~2006年的NOAA AVHRR-GIMMS和MODIS 2种数据集的归一化植被指数(NDVI)数据对东北多年冻土区植被NDVI年际动态和空间差异进行分析,并结合气象数据和土地利用/覆被数据分析了植被NDVI对气候变化和土地利用/覆被变化的响应.研究表明,东北多年冻土区植被NDVI值较高,且空间差异明显;森林为该区主要植被类型,NDVI值较高,主要分布于大小兴安岭和伊春地区;草地集中分布于西南部, NDVI值相对较低.东北多年冻土区过去25a间植被生长的变化趋势为:伴随着气温的显著升高和降水量减少,植被NDVI显著下降.较气温而言,降水量是影响植被NDVI的主要因子(r = 0.77, P < 0.01).在气候变化和人类活动的双重作用下,东北多年冻土区植被NDVI在1982~2006年间表现为4个阶段:1982~1990年,植被NDVI虽有小幅波动,但整体上呈持续增加的趋势;1990~1993年,植被NDVI呈迅速下降趋势; 1993~1997年,植被NDVI呈现回升态势,表现出缓慢上升的趋势;1998~2006年,植被NDVI呈现总体下降趋势.不同植被类型表现出不同的NDVI年际变化规律,尤以草地NDVI值波动最大.植被NDVI变化空间异质性显著.气候变化和多年冻土退化影响了东北多年冻土区植被NDVI动态.年均气温升高和年降水量降低影响了植被的生长.从像元尺度来看,研究区植被NDVI与气温和降水均具有较显著的相关性.研究区土地利用/覆被变化的分析结果表明,不同的土地利用类型间的转变对植被NDVI的大小和空间分布产生了重要影响.  相似文献   

16.
A division of Europe into regions with similar climate and soil conditions, assuming similar pesticide effectiveness and environmental effects of their application, was developed by a combination of statistical cluster analysis and expert involvement for identifying clustering variables and weighing their importance. The experts identified 15 variables representing climatic, soil and crop structure data and weighted them. In order to maximally simplify the administrative work with pesticide registration resulting from the division of Europe into zones, the additional criteria in the procedure were: the zoning follows existing administrative borders, country divisions by zone boundaries are limited, and situations where a zone consists of parts separated by another zone are avoided. The results of the analyses were compared with the applicable EPPO classification and visualized on maps. The highest similarity was observed in the southern Mediterranean zone, the layout of which differed by only a few regions. The Alpine part, having specific conditions, was not distinguished among the EPPO zones. Our study very clearly delineated the Central European part, having a climate with continental influence, which is distributed among other zones in the EPPO classification.  相似文献   

17.
目的 掌握硅基底增透膜在自然环境中的环境适应性。方法 采用棚下暴露试验方法,开展硅基底增透膜样品自然环境试验。以0.5、1、1.5、2 a为检测周期,测试样品外观形貌、微观形貌、光谱透射比和表面化学成分等性能,根据性能随试验时间和试验环境的退化规律来对硅基底增透膜的环境适应性进行评价。结果 经过0.5 a的湿热雨林(版纳站)、暖湿酸雨(江津站)、寒冷(漠河站)、南海岛礁(永兴岛站)气候环境试验,硅基底增透膜光谱透射比出现少量下降,表面部分区域出现了明显的变色和脱膜,样品已失效。随着试验时间的延长,变色和脱膜区域变多、变大,光谱透射比出现明显下降,尤其是经过2 a南海岛礁气候环境试验后,光谱透射比下降了80%左右。结论 对各性能参数进行比较,硅基底增透膜在南海岛礁气候环境中的环境适应性最差,其次是暖湿酸雨气候环境,再次是湿热雨林气候环境,相对好一点的是寒冷气候环境。  相似文献   

18.
渤海沉积物中重金属分布及环境背景值   总被引:29,自引:1,他引:28       下载免费PDF全文
讨论了渤海25柱岩芯样细颗粒(<0.063mm)中重金属含量分布,采用统计学方法确定了底质重金属的分布类型,通过渤海中部岩芯样分析结果,获得渤海沉积物中Cu、Pb、Zn、Cd的环境背景值。在研究中,借助Pb210测年技术测定了百年前沉积层中重金属含量,结果与渤海底质Cu、Pb、Zn和Cd环境背景值是吻合的。  相似文献   

19.
近50a中国西南地区地表干湿状况研究   总被引:22,自引:10,他引:12  
利用1961—2011 年中国西南5 省市113 个气象站的观测资料,基于Penman-Monteith 蒸散模型计算了各个站点逐月潜在蒸散和干湿指数,研究了近50 a 来西南地区气候干湿状况的时空变化特征。结果表明:西南地区气候整体较为湿润,但存在较大的区域差异,呈“东湿西干”的空间分布特征。近50 a 来西南区域的气候有“暖干化”的变化趋势,这种趋势在进入21 世纪以后有进一步加剧的迹象。西南地区干湿季特征鲜明,夏季最为湿润,冬季最干燥。近50 a 来,西南地区的气候干湿状况有两次显著的转变过程,第一次时间点在1992 年前后,此时气候开始湿润化,进入相对湿润期;另一次在2002 年前后,变化趋势由湿润化转为干旱化,进入相对干旱期。降水量是西南地区气候干湿状况的决定因素,日照时数与相对湿度等气象要素对干湿状况也产生较大影响。  相似文献   

20.
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