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阐述了外来物种入侵的三种危害：生态危害;健康危害;经济危害,针对江苏外来物种入侵的当前状况,提出了通过加强已入侵生物的治理和控制,防止其进一步蔓延扩散,加强对外来生物入侵的预防的防治对策。 相似文献
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"生物入侵"是指某种生物从外地自然传入或人为引种后成为野生状态,并对本地生态系统造成一定危害的现象。在缺乏天敌和其他制约因子存在的前提下,入侵种能够快速繁殖和扩增并对当地的生态环境、生物多样性和经济造成严重的损失。随着全球化进程的发展,生物入侵变得更加普遍并且危害更加严重,加强入侵种的治理至关重要。由于传统的物理和化学方法在入侵种防治中存在着一些难以解决的问题,开发和利用无污染、无公害的遗传调控技术在生物入侵种的综合治理方面就显得非常迫切。文章针对我国入侵害虫的现状、主要入侵方式及目前的防治措施进行了总结,同时对遗传调控技术及其在生物入侵种综合治理方面的应用进行了阐述,以期为我国生物入侵的科学治理提供参考。 相似文献
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滨海湿地生境质量演变与互花米草扩张的关系——以江苏盐城国家级珍禽自然保护区为例 总被引：1，自引：0，他引：1
盐城滨海湿地是中国黄（渤）海候鸟栖息地的重要组成部分,生境质量是栖息地功能的重要反映,而互花米草扩张已经严重威胁栖息地生境。因此,本文以1983—2017年10期遥感影像为数据源,基于GIS和RS技术,运用InVEST模型,分析了江苏盐城国家级珍禽自然保护区核心区生境质量时空变化与互花米草扩张的关系。结果显示：①1983—2017年,互花米草扩张与时间呈显著正相关性,面积百分比从1.693%增加到24.930%。在时间上,表现出明显的阶段性特征;在空间上,扩张表现出多方向、多变的特征;②受人类活动和互花米草扩张的影响,生境质量表现出明显波动变化：1983—1988年,生境质量指数从0.863上升至0.878,2014年下降至0.740,2017年又上升至0.775。③互花米草湿地面积变化与生境退化指数变化之间存在正相关,与生境质量指数变化之间呈负相关。互花米草扩张致使区域适宜性生境——碱蓬湿地的面积急剧减少,成为区域生境质量退化的重要因素,控制互花米草扩张也将是区域面临的重要问题。研究结果可从景观格局与生境质量关系的视角为滨海湿地栖息地功能提升与可持续管理提供参考。 相似文献
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红树林是热带亚热带沿海防护林的第一道屏障,素有“海岸卫士”之美誉。红树林有独特的生态、社会和经济价值,尤其在固岸护堤、发展近海渔业、维持生物多样性、净化环境等方面具有重大意义。但令人遗憾的是,多年来全球红树林总面积正以每年超过0.7%的速率减少,如何保护红树林已经成为世界性难题。自20世纪70年代后期,世界各地相继采取减缓红树林退化的措施,在美洲、大洋洲、亚洲等地区进行了造林恢复。然而由于造林地及造林树种选择不当等原因,多数以失败告终。造林成活率低下是制约红树林恢复重建的主要因素,其他因素还有造林树种单一、林带宽度过窄等。近二十年来,互花米草在我国沿海滩涂不断扩散并造成危害,红树林生态系统亦遭受严重威胁。如何在互花米草（Spartina alterniflora Loisel）侵占的滩涂有效控制互花米草并尽快恢复红树林,成为一项新的挑战。 相似文献
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矿山地质灾害给我国矿山开采和生态环境保护带来了很大的危害,因此,研究矿山地质灾害产生的原因,并找出防治措施非常必要。本文论述了矿区存在的几种主要地质灾害的基本特点和致灾原因,从加大宣传力度、提高忧患意识;加大立法力度,建立健全的基于国家层面的法律管控体系;建立矿山生态风险评价体制;建立灾害监测监控预警网络信息系统;因地制宜,综合治理;设立防治基金,完善投入机制几个方面提出了矿山地质灾害的预防与治理措施。 相似文献
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我国土壤侵蚀类型多样、侵蚀过程复杂,相应的水土保持措施丰富。文章对国内外土壤侵蚀及其阻控研究进行了分析,总结了我国复杂环境下土壤侵蚀理论和实践的研究成果;回顾了我国土壤侵蚀防治由优化坡面措施,到小流域综合整治,再到区域生态经济协同发展与优化布局的演变历程。在此基础上,提出了现阶段治理重心应从遏制面积扩张转向生态功能提升为主,治理手段应从综合治理转向生态调控,变对抗为利用,变控制为调节,寻求土壤侵蚀防治与农业高效生产和环境可持续发展的协同途径,以期为国家生态文明建设提供科学依据。 相似文献
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中国科学院鄂尔多斯沙地草地生态研究站（以下简称“鄂尔多斯站”）自建站以来，针对我国沙地草地荒漠化严重的问题，以沙地草地生态系统为研究对象，从各个层次上对草地沙化产生和发展的过程和机理进行长期定位研究，为区域经济可持续发展、荒漠化防治与环境治理提供理论基础和实验示范。30年来，鄂尔多斯站基于长期监测、野外调查和长期控制实验，揭示了气候变化和人类干扰下沙地草地生态系统的过程变化和稳定性的维持机制，引领了沙地植物生态学的研究，在国内外产生重要影响。主要贡献包括：（1）揭示了沙地植物对环境的多样适应对策；（2）阐明了植物性状间耦合关系与生物多样性的大尺度变化规律；（3）探明生物/非生物因子对沙地生态系统结构与功能的调控机制；（4）开创性提出荒漠化综合治理的“三圈”范式，推动了区域可持续发展。为我国沙地生态系统的恢复重建和生态生产功能提升提供理论与技术支撑。 相似文献
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A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
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Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
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Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
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Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
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Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献