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Research Agenda for Understanding Transboundary Ecosystem Changes and Eco-security in Southwestern China 被引量:4
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作者 LIU Jiang HE Daming 《Journal of Mountain Science》 SCIE CSCD 2006年第1期81-90,共10页
The longitudinal range-gorge region (LRGR) in Southwestern China, characterized by longitudinal mountain ranges and deep valleys, includes the basins of four major international rivers: the Yuanjiang-Red, Lancang Meko... The longitudinal range-gorge region (LRGR) in Southwestern China, characterized by longitudinal mountain ranges and deep valleys, includes the basins of four major international rivers: the Yuanjiang-Red, Lancang Mekong, Nujiang Salween and Irrawaddy. This region is classified as one of the world’s biodiversity hotspots, and provides an important ecological and economic corridor linking China and Southeast Asian countries. Over the past half century, it has served as a resource base for timber and minerals needed to fuel economic development, which resulted in rapid and drastic changes in ecosystem and species diversity. Proposed and ongoing development programs, such as China’s Great Western Development campaign, Greater Mekong Subregional Economic Cooperation (GMS) and China-ASEAN free trade zone development (“10+1”), threaten to bring unprecedented disturbance to the region’s ecosystems. Present and emerging threats to eco-security have caught tremendous attention worldwide. Therefore, studies on such problems are critical for enhancing ecosystem health and transboundary eco-security. This paper indicates several multi-disciplinary and cross-sector studies on transboundary resources in this region that will meet three major national needs: 1) identifying core scientific issues of ecological development and infrastructure construction in highplateau and mountainous areas for the Western Development campaign; 2) developing maintenance mechanisms and control methodologies for transboundary eco-security and resource base development; 3) providing scientific grounds for multi-lateral diplomacy, trade and economic cooperation, and conflict resolution as part of China’s opening-up to south Asia. The key subjects to be solved include dynamics and major drive forces of this area, ecological effects caused by major projects construction, and transboundary eco-security and its controlling. The research projects proposed in this article will develop theories on ecosystem change and transboundary eco-security, and provide a scientific basis for national and international development strategies. 展开更多
关键词 Longitudinal range-gorge region transboundary ecosystem changes eco-security Southwestern China
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Tourism Destination Eco-Security and Its Dynamic Evaluation Method 被引量:1
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作者 SU Qiaolan 《Journal of Landscape Research》 2013年第Z1期35-37,40,共4页
Ecological security of tourism destination is an important factor for the sustainable development of tourism industry, and many tourism destinations are threatened by various ecological problems. A complete understand... Ecological security of tourism destination is an important factor for the sustainable development of tourism industry, and many tourism destinations are threatened by various ecological problems. A complete understanding of eco-security situation is the foundation of maintaining sustainable development for tourism destinations. However, study on tourism destination eco-security has remained in the initial stage, based on domestic and international researches, the connotations and dynamic characteristics of tourism destination eco-security were discussed. Then, evaluation method of tourism destination eco-security and standard system were proposed, also dynamic evaluation method of tourism destination eco-safety based on the situation evaluation and trend was analyzed. 展开更多
关键词 TOURISM DESTINATION eco-security P-S-R MODE DYNAMIC EVALUATION
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Performance Analysis of Physical Layer Security over α-η-κ-μ Fading Channels 被引量:1
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作者 Shaobo Jia Jiayan Zhang +1 位作者 Honglin Zhao Yao Xu 《China Communications》 SCIE CSCD 2018年第11期138-148,共11页
In this paper, we consider the secure data transmission over α-η-κ-μ fading channels, which are recently proposed to encompass nearly all the well-known statistical models adopted in the literature. In particular,... In this paper, we consider the secure data transmission over α-η-κ-μ fading channels, which are recently proposed to encompass nearly all the well-known statistical models adopted in the literature. In particular, we address the secrecy performance in terms of the average secrecy capacity(ASC) and the secrecy outage probability(SOP), for which novel analytical expressions are derived. Simulation results verify the analysis and demonstrate the impact of the physical parameters on the secrecy performance of this new channel fading model. 展开更多
关键词 Physical layer security α-η-κ-μgeneralized fading channels average secrecycapacity secrecy outage probability
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Systematic Design and Coordination Acts of Ecological Security in Upper Yangtze River in China 被引量:1
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作者 Fang Yi-ping, Chen Quo-jieInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan. China School of Management, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期987-995,共9页
In this paper, systematic design and act of eco-security is discussed as a focal point of conflict and unrest. The situation of ecosystem, the schematic framework of eco-security design, the main acts of ecosystem imp... In this paper, systematic design and act of eco-security is discussed as a focal point of conflict and unrest. The situation of ecosystem, the schematic framework of eco-security design, the main acts of ecosystem improvement, major difficulties and challenges have also been analyzed. The purpose of this study was to formulate the systematic framework of eco-security maintenance, to highlight systematic idea or philosophy of ecological rehabilitation and eco-security. A three-dimensional schematic model is applied to design the security of ecosystem. It was concluded that: 1) maintaining ecological security requires far better and sophisticated resource management skill and ecological improvement measures, and is also a continuing and multifac-eted task. It cannot be permanently accomplished by a single action and program; 2) at present, technical system and policy and law system dimensions of ecological security are not enough even in short; 3) development of ecological industries is beneficial to local economic development and ecosystem protection. 展开更多
关键词 upper Yangtze basin ecological security systematic design eco-security maintenance
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The effectiveness of the department of defense's field manual 3-11 in detecting,deterring and degrading the breach of a combat base by a human-borne with bioagent(HBBA):perceptions of security personnel
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作者 George Edafese Alakpa John W.Collins Jr 《Journal of Medical Colleges of PLA(China)》 CAS 2016年第2期66-72,共7页
Background: The department of defense's field manual(FM) 3-11 is among the military's field manuals for preparing for, reacting to and recovering from chemical, biological, radiological and nuclear attacks. Si... Background: The department of defense's field manual(FM) 3-11 is among the military's field manuals for preparing for, reacting to and recovering from chemical, biological, radiological and nuclear attacks. Since post 9-11, U.S. military service members have been deployed in the global war on terrorism. This study attempted to determine the effectiveness of the FM 3-11 in detecting, deterring or preventing a human-borne with bioagent(HBBA) terrorist breach at an entry control point(ECP).Methods: This time-specific, cross-sectional study disseminated a validated survey tool with Cronbach's α>0.82 to respondents who have had antiterrorism training and combat ECP experience. The return rate was greater than 75.0%; however, many of the respondents failed to meet the inclusion criteria. Consequently, only 26 questionnaires were included in the sample.Results: The results revealed that while over 60.0% of the respondents either strongly agreed or agreed that biointelligence, the deployment of biodetectors and the use of biowarning systems could be effective in preventing an ECP breach by a terrorist with a bioagent, the use of protective equipment and immunization to decontaminate service members or other tactics, techniques and procedures(TTPs) would never prevent a breach. A large percentage of respondents claimed that soldiers at the ECP lacked the devices or the knowledge to detect an HBBA at an ECP, and 72.0% suggested modifying current ECP TTPs to include education, training and equipment for security personnel at military base ECPs.Conclusion: If obtained from appropriate sources and communicated to the personnel at the ECP in an effective or timely manner, the possible effectiveness of certain TTPs in the FM 3-11, specifically FM 3-11.86(intelligence), might increase. 展开更多
关键词 Do D FM 3-11 BIOTERRORISM Breach of COMBAT ECP HBBA TERRORIST security PERSONNEL Perception
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Special Plan for Population,Employment and Social Security Between 2001-2005
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《China Population Today》 2002年第1期2-4,共3页
关键词 security Special Plan for Population Employment and Social security Between 2001-2005
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Enhancement of Multicast Security with Opportunistic Relaying Technique over κ-μ Shadowed Fading Channels
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作者 Ashik Alam Md. Zahurul Islam Sarkar 《Journal of Computer and Communications》 2022年第11期121-137,共17页
The effects of scatterers, fluctuation parameter and propagation clusters significantly affect the performance of κ-μ shadowed fading channel. On the other hand, opportunistic relaying is an efficient technique to i... The effects of scatterers, fluctuation parameter and propagation clusters significantly affect the performance of κ-μ shadowed fading channel. On the other hand, opportunistic relaying is an efficient technique to improve the performance of fading channels reducing the effects of aforementioned parameters. Motivated by these issues, in this paper, a secure wireless multicasting scenario through κ-μ shadowed fading channel is considered in the presence of multiple eavesdroppers with opportunistic relaying. The main purpose of this paper is to ensure the security level in wireless multicasting compensating the loss of security due to the effects of power ratio between dominant and scattered waves, fluctuation parameter, and the number of propagation clusters, multicast users and eavesdroppers, by opportunistic relaying technique. The closed-form analytical expressions are derived for the probability of non-zero secrecy multicast capacity (PNSMC) and the secure outage probability for multicasting (SOPM) to understand the insight of the effects of above parameters. The results show that the loss of security in multicasting through κ-μ shadowed fading channel can be significantly enhanced using opportunistic relaying technique by compensating the effects of scatterers, fluctuation parameter, and the number of propagation clusters, multicast users and eavesdroppers. 展开更多
关键词 Opportunistic Relaying Probability of Non-Zero Secrecy Multicast Capacity (PNSMC) secure Wireless Multicasting secure Outage Probability for Multicasting (SOPM) κ-μ Shadowed Fading Channel
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基于FSS-ECO环境安全功能性服装产业创新升级研究 被引量:4
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作者 洪文进 唐颖 沈雷 《毛纺科技》 CAS 北大核心 2015年第10期68-71,共4页
在FSS-ECO环境下,面对纺织服装行业劳动力生产力成本提高、原料价格不断上涨等现实产业问题的影响,为了促进安全性功能服装产业设计作为当前服装产业转型升级的新手段,从而转变产品设计的新思路。文章重点分析了制约当前安全功能性服装... 在FSS-ECO环境下,面对纺织服装行业劳动力生产力成本提高、原料价格不断上涨等现实产业问题的影响,为了促进安全性功能服装产业设计作为当前服装产业转型升级的新手段,从而转变产品设计的新思路。文章重点分析了制约当前安全功能性服装产业发展的内在原因及其产业升级的必然性,深入探析安全功能性服装在整体设计过程中所面临的问题以及在设计中的重点与难点,同时提出了安全功能性服装产业需依赖产业结构的调整变化、设计理念的转变、产品的技术文化创新以及品牌运营管理创新与生产管理建设等系列产业化创新升级的战略。进一步突显了安全功能性服装在现代服装产业转型升级中的地位,为整体产业创新升级研究奠定了基础理论研究。 展开更多
关键词 FSS-eco 安全功能性 服装产业 创新升级 技术
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Close Relationship between the Frangibility of Mountain Eco-Environment and Mountain Disasters:A Case Study of Dongchuan,Kunming in Yunnan Province 被引量:2
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作者 WANG Yuyi TIAN Bing LIU Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期721-728,共8页
Anatomical details are given in this article, which is performed by investigating the relationship between through the frangibility of mountain eco-environment and the status of irrational land-use in typical region o... Anatomical details are given in this article, which is performed by investigating the relationship between through the frangibility of mountain eco-environment and the status of irrational land-use in typical region of debris flow in Dongchuan district, Kunming city, yunnan Province. This analysis is extended to the relationship between vicissitude of mountain disasters and the frangibility of mountain environment. The relatively coupling action of a vicious circle is a evolving characteristic by debris flow sand-gravel there. The eco-security is being faced with serious challenge. The tactics of eco-security has been constructed since 1980s. Thus, the eco-environrnent can gradually be repaired and optimized to achieve a fine circle. 展开更多
关键词 eco-ENVIRONMENT frangibility mountain disasters eco-security
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Ecological Effects of Remote Smallsand Descending on Urban Area:Deduced from the "Mud - Snow" in Changchun City 被引量:2
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作者 Wu Donghui Hu Ke +3 位作者 Wang Yun Yang Deming Zhao Wei Chen Shan 《Global Geology》 2000年第2期230-235,共6页
A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with sn... A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with snow provides the best samples to conduct a quantitative research on the possible impacts of city - ecology. In the 253km2 urban district area of Changchun city, smallsands accumulated up to more than 3000t on April 7, according to the calculation of four "mud - snow" samples. After naturally melting in room temperature, two samples are taken to do quarantine of "invasion bacteria". As a preliminary result, the individual amount of bacterium in 1 ml sample water is up to 8. 9 x 104 or 1. 05 x 105, and it is estimated that there are 640 million "invasion bacterium" individuals in one square meter. This study proves that other than the obvious environmental effects of sandstorm, the urban micro - ecosystem is very possible under threat by the "invasion bacterium" accompanied by remote descending smallsand. 展开更多
关键词 REMOTE smallsand Bacteria - total ecoLOGICAL security Changchun city
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Study on the Reform of Agricultural Supply Side Based on Food Security 被引量:1
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作者 Jierong WANG Junying WEI 《Asian Agricultural Research》 2017年第4期8-10,共3页
In December 2015,the Central Rural Work Conference put forward the structural reform of agricultural supply side,to ensure the national food security. At present,China's grain production is increasing,the supply a... In December 2015,the Central Rural Work Conference put forward the structural reform of agricultural supply side,to ensure the national food security. At present,China's grain production is increasing,the supply and demand structure of grain market is not balanced,and the ineffective supply due to the lack of market supply and demand has caused the problem of structural surplus and structural shortage.And price and quality difference of domestic and international grain is obvious,and the agricultural products in China are overstock,so the reform of agricultural supply side based on food security must be implemented. To adjust structure,reduce stock,reduce cost,increase quality,promote the primary,secondary and tertiary industries convergence will become the focus of China's agricultural supply side structural reform,and we can develop the ecological agriculture,improve the competitiveness of the grain market in price and quality,to ensure food security for the nation. 展开更多
关键词 Food security Agricultural supply side Price mechanism eco-agriculture Industry convergence
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“边境-粮食-生态”安全视域下耕地利用生态效率演变特征与机制——以中越边境地区为例
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作者 王鹏程 张利国 陆汝成 《生态学报》 CAS CSCD 北大核心 2024年第11期4637-4649,共13页
明晰耕地利用生态效率的驱动机理是深化土地科学前沿探索、优化粮食安全发展格局的关键基础。建构“边境-粮食-生态”安全框架,采用非期望产出的超效率SBM模型测算2000—2020年中越边境地区耕地利用生态效率,通过泰尔指数研究其演变特... 明晰耕地利用生态效率的驱动机理是深化土地科学前沿探索、优化粮食安全发展格局的关键基础。建构“边境-粮食-生态”安全框架,采用非期望产出的超效率SBM模型测算2000—2020年中越边境地区耕地利用生态效率,通过泰尔指数研究其演变特征和区域差异,并运用动态面板系统GMM模型揭示耕地利用生态效率的驱动机制。结果表明:(1)中越边境地区耕地利用生态效率指数总体呈现“先升-后降-再升”的变化趋势,整体处在中等效率水平,空间表现为“北高-南低”分布格局,省际差异是造成区域差异的主要原因。(2)化肥使用过量、劳动力过剩和碳排放增加是造成中越边境地区耕地投入产出要素松弛、耕地利用生态效率损失的重要因素。(3)中越边境地区耕地利用生态效率由多因子交互作用驱动,地形坡度、城镇化、边境贸易水平、财政支农水平是提高耕地利用生态效率的积极因素,水土流失率、工业化和劳均耕地规模对耕地利用生态效率具有抑制效应。中越边境地区亟需优化耕地经营投入结构,向“投入优-产出高-排放低”方向转型,构建边境粮农稳态格局,促进边境地区长足稳定高质量发展。 展开更多
关键词 耕地利用生态效率 驱动机制 边境安全 动态面板系统GMM 中越边境地区
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United States Healthcare Data Breaches: Insights for NIST SP 800-66 Revision 2 from a Review of the NIST SP 800-66 Revision 1
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作者 Mohammed Mohammed Raoof 《Journal of Information Security》 2024年第2期232-244,共13页
Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publicati... Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publication base as an effective solution. The NIST Special Publication 800-66 Revision 1 was an essential standard in US healthcare, which was withdrawn in February 2024 and superseded by SP 800-66 Revision 2. This review investigates the academic papers concerning the application of the NIST SP 800-66 Revision 1 standard in the US healthcare literature. A systematic review method was used in this study to determine current knowledge gaps of the SP 800-66 Revision 1. Some limitations were employed in the search to enforce validity. A total of eleven articles were found eligible for the study. Consequently, this study suggests the necessity for additional academic papers pertaining to SP 800-66 Revision 2 in the US healthcare literature. In turn, it will enhance awareness of safeguarding electronic protected health information (ePHI), help to mitigate potential future risks, and eventually reduce breaches. 展开更多
关键词 SP 800-66 Revision 1 SP 800-66 Revision 2 HIPAA Compliance security Breaches Risk Management Framework (RMF) Internet of Things (IoT) Artificial Intelligence (AI)
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干旱区内陆河流域的生态安全与生态需水量研究--兼谈塔里木河生态需水量问题 被引量:62
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作者 陈亚宁 郝兴明 +3 位作者 李卫红 陈亚鹏 叶朝霞 赵锐锋 《地球科学进展》 CAS CSCD 北大核心 2008年第7期732-738,共7页
结合对干旱区生态安全和生态需水量关键科学问题的探讨,提出干旱内陆河流域生态脆弱区的生态安全分析是以水过程研究为核心的,水文过程控制着生态过程,对流域生态系统的稳定性有着直接影响,而水资源开发利用和水循环对生态系统功能有重... 结合对干旱区生态安全和生态需水量关键科学问题的探讨,提出干旱内陆河流域生态脆弱区的生态安全分析是以水过程研究为核心的,水文过程控制着生态过程,对流域生态系统的稳定性有着直接影响,而水资源开发利用和水循环对生态系统功能有重要影响,天然植物恢复和生长的合理地下水位的研究是确立生态需水量的基础。并实证分析和计算了维系塔里木河生态安全的生态需水量,塔里木河干流现状生态需水量为31.74×108m3,其中,上、中、下游分别为9.95×108m3、18.47×108m3和3.32×108m3。 展开更多
关键词 生态安全 生态需水量 生态水文过程 塔里木河
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基于GIS-Markov区域生态安全时空演变研究——以大连市甘井子区为例 被引量:24
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作者 王耕 王嘉丽 +2 位作者 龚丽妍 苏柏灵 刘秋波 《地理科学》 CSCD 北大核心 2013年第8期957-964,共8页
以大连市甘井子区为例,基于压力-状态-响应(P-S-R)框架构建区域生态安全评价体系,利用研究区1990年、2000年和2009年3期TM遥感影像数据,在GIS格网技术下量化多源数据,创建区域生态安全格网数据库,采用加权综合评价方法进行生态安全状... 以大连市甘井子区为例,基于压力-状态-响应(P-S-R)框架构建区域生态安全评价体系,利用研究区1990年、2000年和2009年3期TM遥感影像数据,在GIS格网技术下量化多源数据,创建区域生态安全格网数据库,采用加权综合评价方法进行生态安全状态评价。以评价结果为基础,构建区域生态安全GIS-Markov模型,通过计算区域生态安全状态转移矩阵,揭示区域生态安全时空演变特点。研究结果表明:①1990~2009年甘井子区各街道生态安全指数逐年增加,其中1990~2000年生态安全变化较大的地区集中于甘井子北部和中部,西部和南部地区生态安全变化较小;2000~2009年除泉水街道与南关岭街道外,其他地区生态安全状况均大幅好转。②区域背景在生态安全空间演变趋同过程中起着重要的作用。甘井子区生态安全演变的可能性受邻域的影响,安全等级较高的邻域对生态安全等级转移起到正面作用,而安全等级较低的邻域则产生负向影响。1990~2000年,甘井子区生态安全状态受较高安全等级邻域的影响,安全状态好转的面积较大,营城子街道北部及革镇堡街道西部的农村地区受较低安全等级邻域的影响,安全状态变差。2000~2009年,甘井子区生态安全总体向好的方面转变,受邻域的影响较小,只有泉水街道及营城子街道与红旗街道交界处受不安全邻域影响,其生态安全状况转差。 展开更多
关键词 生态安全 GIS-Markov 时空演变 大连甘井子区
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快速城市化区域生态安全的空间模糊综合评价--以广州市为例 被引量:40
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作者 龚建周 夏北成 陈健飞 《生态学报》 CAS CSCD 北大核心 2008年第10期4992-5001,共10页
随着经济的快速发展,城市生态安全状况令人担忧。进行城市生态安全评价,了解城市生态安全状况成为城市生态建设、改善和提高城市生态安全状况的前提。基于TM遥感数据以及GIS平台,构建评价指标体系,采用空间模糊评价方法进行生态安全的... 随着经济的快速发展,城市生态安全状况令人担忧。进行城市生态安全评价,了解城市生态安全状况成为城市生态建设、改善和提高城市生态安全状况的前提。基于TM遥感数据以及GIS平台,构建评价指标体系,采用空间模糊评价方法进行生态安全的空间综合评价,进而分析其时间与空间变化。生态安全空间分布图及其属性的统计结果表明,整体上讲,广州市生态安全等级为一般,并且随时间推移,生态安全状态比较稳定,但是在1995年受到较大的破坏;不同区域之间生态安全的对比分析显示,广州市生态安全的城乡差异明显,中心城区生态安全状态堪忧;将研究结果与作者早已经完成的同区域基于统计数据的生态安全评价分析结果进行趋势对比,二者显示出一致性,表明基于格网的空间模糊综合评价方法用于生态安全评价是可行的,研究的设计也是合理的,但是这种空间综合评价方法却具有传统方法不具备的优点:不仅具有可视化的表达效果,还有利于不同范围大小区域之间的对比研究。 展开更多
关键词 区域生态安全 空间模糊评价 3S 变权 广州
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生态安全条件下土地利用格局优化--以皇甫川流域为例 被引量:23
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作者 喻锋 李晓兵 王宏 《生态学报》 CAS CSCD 北大核心 2014年第12期3198-3210,共13页
在人类活动导致的生态环境问题中,土地利用格局变化对区域生态安全起着决定性作用。选择我国乃至在世界上都罕见的多沙、粗沙、强烈水土流失的黄河皇甫川流域作为研究区域,针对土壤侵蚀和生态用水这两大影响流域生态安全的关键问题,开... 在人类活动导致的生态环境问题中,土地利用格局变化对区域生态安全起着决定性作用。选择我国乃至在世界上都罕见的多沙、粗沙、强烈水土流失的黄河皇甫川流域作为研究区域,针对土壤侵蚀和生态用水这两大影响流域生态安全的关键问题,开展土地利用变化模拟、土壤侵蚀3S监测、适宜植被盖度估算、土壤侵蚀情景模拟、土地利用格局优化等方面的综合研究。结果表明:(1)土地利用格局变化是导致土壤侵蚀变化的重要因素。从1987年到2015年,建筑用地、林地和灌丛面积增加,水域、沙地和裸砒砂岩面积减少,导致流域年平均土壤侵蚀模数由16160.72 t km-2a-1降至9710.72 t km-2a-1。(2)土地利用类型与土壤侵蚀模数密切相关并存在一定规律。6种不同土地利用类型多年平均土壤侵蚀模数的大小顺序为:裸砒砂岩>沙地>耕地>草地>林地>灌丛,表明灌、林措施是流域植被恢复和土壤侵蚀减少的首选。(3)土地利用结构和空间格局优化有助于提升区域生态安全水平。在优化格局下,2007年和2015年土壤侵蚀模数比优化前分别减少5469.57 t km-2a-1和5432.77 t km-2a-1,优化后2015年土壤侵蚀模数仅为4277.95 t km-2a-1,低于流域自然侵蚀临界值或允许土壤侵蚀模数5300 t km-2a-1,优化土地利用格局成为加强流域生态环境建设的重要途径。 展开更多
关键词 生态安全 土地利用 土壤侵蚀 适宜植被盖度 格局优化
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基于P-S-R模型的土地生态安全物元评价——以河南省为例 被引量:29
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作者 刘蕾 姜灵彦 高军侠 《地域研究与开发》 CSSCI 北大核心 2011年第4期117-121,共5页
采用P-S-R模型建立指标体系,对区域土地资源生态安全进行客观评价。采用物元和可拓理论构建了区域土地资源生态安全综合评价模型,以河南省为例进行了研究,用层次分析法进行结果计算。结果表明:研究区域内耕地粮食单产逐年增加,土地流失... 采用P-S-R模型建立指标体系,对区域土地资源生态安全进行客观评价。采用物元和可拓理论构建了区域土地资源生态安全综合评价模型,以河南省为例进行了研究,用层次分析法进行结果计算。结果表明:研究区域内耕地粮食单产逐年增加,土地流失比例逐年降低,土地质量不断提高,森林覆盖率提高,生态环境得到有效改善,但人口压力过大,人均耕地面积不足仍然是影响土地生态安全的重要因素;GDP总量较大,但人均占有量较少,第三产业占国民收入的比重虽有所提升,但横向比较与全国平均水平仍有差距;产业结构、城乡结构不合理已经成为经济社会发展最突出矛盾,加快转变经济发展方式尤为紧迫。整体水平不容乐观,目前仍处于临界安全水平,评价结果符合当地实际情况。基于P-S-R模型的物元评价方法适用于土地生态安全评价,有一定的推广价值。 展开更多
关键词 土地资源 生态安全 压力-状态-响应模型 物元分析 河南省
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基于改进DPSIR-DS模型的旅游生态安全等级测度及时空演变分析——以“丝绸之路”沿线五省区为例 被引量:43
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作者 翁钢民 潘越 李凌雁 《旅游科学》 CSSCI 北大核心 2018年第6期17-32,共16页
针对当前旅游生态安全等级评估中"非此即彼"的问题,本文基于"驱动力-压力-状态-影响-响应(DPSIR)"模型,构建了旅游生态安全评价指标体系,运用改进的D-S证据理论对"丝绸之路"沿线五省区2007年、2009年、2... 针对当前旅游生态安全等级评估中"非此即彼"的问题,本文基于"驱动力-压力-状态-影响-响应(DPSIR)"模型,构建了旅游生态安全评价指标体系,运用改进的D-S证据理论对"丝绸之路"沿线五省区2007年、2009年、2011年、2013年和2015年的旅游生态安全等级进行了动态评估,并对其时空演变进行了分析。结果表明:从2007年到2015年,"丝绸之路"旅游生态安全等级沿着"风险-敏感-风险"方向演变,总体处于较低安全等级;"丝绸之路"沿线五省区的旅游生态安全等级均位于Ⅰ~Ⅳ,根据安全等级的演变趋势,将旅游生态安全等级演变类型划分为风险缓解型、风险加剧型和风险反复型3种,其中,新疆、宁夏和陕西属于风险缓解型区域,青海为风险加剧型区域,甘肃为风险反复型区域;各安全等级之间转换频繁,但未发生跳跃式转移的情况。研究结果可为管理与监控"丝绸之路"旅游生态安全提供理论依据和决策参考。 展开更多
关键词 改进DPSIR DS模型 旅游生态安全 动态评价 丝绸之路
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基于粮食安全保障的土地整理区域差异与对策研究--以四川省为例 被引量:4
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作者 张素兰 严金明 +1 位作者 高成凤 于丽娟 《资源开发与市场》 CAS CSSCI 2009年第5期432-436,共5页
分析粮食与耕地资源态势,研究省域土地整理区域差异与对策,为合理制定土地整理规划目标、确保粮食安全提供科学依据。研究结果表明,四川耕地质量差,耕地后备资源贫乏,人地矛盾日益尖锐,粮食安全保障问题日益凸显。为确保粮食安全,经济... 分析粮食与耕地资源态势,研究省域土地整理区域差异与对策,为合理制定土地整理规划目标、确保粮食安全提供科学依据。研究结果表明,四川耕地质量差,耕地后备资源贫乏,人地矛盾日益尖锐,粮食安全保障问题日益凸显。为确保粮食安全,经济较发达、人地矛盾尖锐的成都平原区和盆地丘陵区应以农村居民点和农地整理为主,加强中低产田土改造,从深度上挖掘耕地资源潜力,提高耕地粮食综合生产能力;经济较落后的川西南山地区、盆周山地区和川西北高山高原区,土地整理应与退耕还林、治水治沙相结合,改善生态环境,搞好灾后土地整理复垦规划,加强土地整理复垦工作。全省应重点抓好成都平原区农村居民点整理、川南喀斯特地貌农地和炼磺污染地整理、攀西地区土地复垦开发重点工程,以及地震灾区土地整理复垦、生态恢复与重建。 展开更多
关键词 粮食安全保障 土地整理 区域差异 生态环境 灾区土地整理复垦 四川省
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