全球气候变化对我国气候安全影响的思考

依据政府间气候变化专门委员会 (IPCC) 第5次评估报告以及国内相关科学研究成果,使用最新的观测资料凝练了对全球气候变化的有关认识;从极端天气气候事件和气候承载力角度,分析了气候变化给我国带来的气候风险。研究发现:1961—2015年我国平均高温日数增加了28.4%,暴雨日数增加了8.2%。21世纪以来,登陆我国热带气旋的强度明显增加。在全球气候变暖的背景下,我国气候承载力将发生明显变化,未来面临的气候风险将加大。因此,保障我国气候安全,需要科学认识气候,提高气候风险意识; 主动适应气候,提高应对极端事件能力;努力保护气候,减缓气候变化的影响。     

盐度对口虾蛄仔虾摄食、存活和掘穴的影响

为研究口虾蛄(Oratosquilla oratoria)仔虾在人工养殖条件下的盐度适应性,作者分别实验分析了盐度突变和渐变对其累积存活率、摄食率和掘穴行为的影响。实验结果表明,仔虾盐度耐受能力较强,突变组的仔虾存活盐度为15~45,渐变组的仔虾存活盐度为5~54;仔虾的适宜盐度为21~33,24 h存活率在80%以上;盐度对口虾蛄的摄食影响较大,突变盐度为21~33时,仔虾摄食较为活跃,低于18或高于42基本不摄食;盐度渐变组摄食活跃范围为19~38,低于9或高于50基本不摄食;盐度突变对口虾蛄仔虾掘穴的影响显著,盐度突变至21和33时,掘穴时间极显著延长。本实验结果可以为口虾蛄的人工养殖和增殖放流提供参考和依据。     

气候变化对中国国家安全的影响

基于政府间气候变化专门委员会(IPCC)第四次评估报告和2007年中国发布的气候变化国家评估报告的结果,整理、分类和提炼出关系中国国家安全的气候变化要素及其影响的演变趋势和区域响应特征,并分析其产生的安全后果.结果表明,基础设施的损毁、基础自然资源的缺失以及人民生命财产损失是气候变化产生的三个关键社会经济影响.气候变化...     

Climate shocks and political violence

The dominant discourse on the security implications of climate change has asserted that acute environmental scarcity—such as that caused by drought—causes political violence. In contrast, we argue that there are good reasons why water scarcity might have a pacifying effect on armed conflict, and that political violence should be more prevalent during periods of comparatively better agro-climatic conditions. Political violence is more prevalent when basic needs are met and when the tactical environment is more conducive to attacks—conditions that hold when water is comparatively abundant. Empirically, this paper explores the relationship between environmental scarcity and political violence in a global sample of countries, 1970–2006. We find that water abundance is positively correlated with political violence, and that this relationship is stronger in less developed, more agriculturally dependent societies. These findings are robust to several different operationalizations of our variables. We conclude with a brief discussion of the policy implications of our findings.     

基于WCF的矢量数据服务安全机制的设计与实现

21世纪计算机技术和网络技术的飞速发展将地理信息产业带进了一个崭新的领域.地理空间信息服务成为解决数据异构、实现资源共享的有效途径.然而,随着地理信息服务在各领域的推广应用,传统分布式技术在开发地理信息网络服务中所面临的安全问题逐渐突显出来,已严重制约了网络服务在地理信息产业的发展.针对矢量数据服务在数据传输、服务操作...     

Comparative biomass structure and estimated carbon flow in food webs in the deep Gulf of Mexico

A budget of the standing stocks and cycling of organic carbon associated with the sea floor has been generated for seven sites across a 3-km depth gradient in the NE Gulf of Mexico, based on a series of reports by co-authors on specific biotic groups or processes. The standing stocks measured at each site were bacteria, Foraminifera, metazoan meiofauna, macrofauna, invertebrate megafauna, and demersal fishes. Sediment community oxygen consumption (SCOC) by the sediment-dwelling organisms was measured at each site using a remotely deployed benthic lander, profiles of oxygen concentration in the sediment pore water of recovered cores and ship-board core incubations. The long-term incorporation and burial of organic carbon into the sediments has been estimated using profiles of a combination of stable and radiocarbon isotopes. The total stock estimates, carbon burial, and the SCOC allowed estimates of living and detrital carbon residence time within the sediments, illustrating that the total biota turns over on time scales of months on the upper continental slope but this is extended to years on the abyssal plain at 3.6 km depth. The detrital carbon turnover is many times longer, however, over the same depths. A composite carbon budget illustrates that total carbon biomass and associated fluxes declined precipitously with increasing depth. Imbalances in the carbon budgets suggest that organic detritus is exported from the upper continental slope to greater depths offshore.The respiration of each individual “size” or functional group within the community has been estimated from allometric models, supplemented by direct measurements in the laboratory. The respiration and standing stocks were incorporated into budgets of carbon flow through and between the different size groups in hypothetical food webs. The decline in stocks and respiration with depth were more abrupt in the larger forms (fishes and megafauna), resulting in an increase in the relative predominance of smaller sizes (bacteria and meiofauna) at depth. Rates and stocks in the deep northern GoM appeared to be comparable to other continental margins where similar comparisons have been made.     

RS和GIS支持下的县域生态安全评价

人类社会的发展迅速影响着自然环境、改变着自然生态系统,致使生态安全形势越来越严峻,局部地区生态的破坏已经威胁到社会经济与农业生产可持续发展的基础。在这种状况下,生态安全研究就显得极为重要。本文采用层次分析法对丹巴县进行RS和GIS支持下的生态安全评价,由生态安全评价结果可知丹巴县生态安全总体堪忧。     

加强我国土地利用/覆盖变化及其对生态环境安全影响的研究——-从荷兰“全球变化开放科学会议”看人地系统动力学研究的发展趋势

综述了在荷兰阿姆斯特丹召开的"全球变化开放科学会议"的主要学术成果,从中分析了在全球变化研究的各个领域,人类活动在全球变化中所起作用的重要方面。在此基础上,阐述了我国如何加强在全球变化和可持续发展研究中,开展土地利用/覆盖变化及其对生态环境安全影响研究的重要方向。以此研究揭示土地利用变化的驱动力,土地覆盖变化的生态效应,土地利用/覆盖格局对生态环境安全的影响机理。着眼我国生态系统对全球变化的可能响应,重构了我国生态环境安全条件下的土地利用/覆盖的空间宏观格局。     

中高渗倾斜地层与水平地层中CO2地质封存的差异性对比

CO2地质封存是减少CO2向大气排放,缓解温室效应的有效手段之一。由于构造和成岩作用,倾斜地层在自然界中普遍存在,研究倾斜地层对CO2封存量及安全性的影响具有实际意义。依托新疆准噶尔盆地阜康凹陷某CO2地质封存示范工程,采用数值模拟方法,分析了中高渗CO2储层地层倾角变化对CO2地质封存过程的影响。结果表明:CO2注入将导致近井区域地层压力显著升高;中高渗倾斜地层与水平地层相比,在地层压力分布、CO2侧向运移距离、CO2注入速率和总封存量等方面均存在明显差异。相比于水平地层,由于地层倾角的存在,倾斜地层压力呈不对称分布,CO2侧向运移距离显著加大。倾斜地层中压力传递和消散过程与水平地层差异显著,受此影响,倾斜地层与水平地层CO2的总注入量差值随时间呈非单调性变化。在注入初期,倾斜地层CO2的总注入量小于水平地层,随着注入时间延长,倾斜地层CO2的总注入量逐渐接近并超过水平地层;注入20年后,相较于水平地层,倾斜地层倾角越大越有助于增加CO2的总注入量,这一研究结果与前人基于低渗倾斜地层的研究结论正好相反。地层倾角的存在会促进CO2向浅部运移,倾角越大,CO2向浅部含水层和大气泄露的风险越大。因此,在CO2地质封存场地选址中,应充分考虑倾斜地层对封存效率及安全性的影响。     

网络化的测绘生产

数字测绘生产的网络化管理,大大提高了浏绘数据的生产效率,以及数据的高效率存储,增强了测绘生产在网络环境中的安全性.