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1.
华北高产粮区农用水资源可持续发展利用对策研究 总被引：6，自引：0，他引：6
水资源短缺严重制约了华北高产粮区农业的可持续发展。本文对华北地区农业可持续发展的水问题况进行了阐述，对华北高产粮区的典型区域山东省桓台县农用水资源利用现状进行了分析，指出水资源浪费、污染严重，水资源管理不善是水资源利用过程中存在的最主要问题。并在区域、农户、农田三个层次上提出了农用水资源可持续利用对策。 相似文献
2.
华北高产粮区农用水资源可持续利用对策研究——以山东省桓台县为例 总被引：5，自引：0，他引：5
水资源短缺严重制约了华北高产粮区农业的可持续发展。本文对华北地区农业可持续发展的水问题况进行了阐述 ,对华北高产粮区的典型区域山东省桓台县农用水资源利用现状进行了分析 ,指出水资源浪费、污染严重 ,水资源管理不善是水资源利用过程中存在的最主要问题。并在区域、农户、农田三个层次上提出了农用水资源可持续利用对策。 相似文献
3.
我国水资源短缺可划分为人为超采短缺型和环境因素造成的水资源短缺型。文章针对不同类型的水资源短缺,提出了不同的解决对策,即：人为超采短缺型可通过截流地表水人工补给,进行水资源时空调控加以解决;环境因素造成的水资源短缺型可通过开发深部地下水加以解决。 相似文献
4.
本文概述了我国水资源短缺的成因、类型和解决对策。从成因上划分,我国水资源短缺可划分为人为超来短缺型和环境因素造成的水资源短缺型两种类型,人为超采短缺型可通过截流地表水人工补给,进行水资源时空调控加以解决;环境因素造成的水资源短缺型可通过开发深部地下水加以解决。不论明阿中方式,充分利用科技手段则都是必须的。 相似文献
5.
我国区域间虚拟水贸易的探讨 总被引：2，自引：0，他引：2
水资源短缺一直是制约我国经济发展的重要因素,笔者基于我国南北地区间水资源禀赋差异大的特点,提出应通过区域间的虚拟水贸易解决区域水资源短缺、水环境污染等问题.并对我国区域间虚拟水贸易战略的必要性、可行性以及可能产生的问题及对策展开分析. 相似文献
6.
南水北调东线受水区水资源优化配置模型 总被引：3，自引：0，他引：3
南水北调东线工程是我国南水北调总体布局中的重要组成部分，对其水资源进行优化配置将缓解受水区的水资源短缺问题及促进该区域的社会经济发展。根据南水北调工程东线受水区的特点,将其划分为3个子区、5个用水部门，选用国内生产总值最大、区域总缺水量最小、区域重要污染物排放量最小为目标，以水源可供水量、水源至用户的输水能力、用户需水量、区域协调发展等为约束条件，结合水源供水次序系数、用户用水公平系数、需水量、水源供水量等参数，共同构成了该区域的水资源优化配置模型。通过对模型的计算结果进行分析发现,在2010年和2030年，南水北调东线工程受水区的各用水部门中，生活、环境、航运、工业用水都可以满足，只有农业用水出现短缺；南水北调工程东线受水区水资源利用与经济发展协调度较好，而经济发展与环境保护之间的协调较差，整个区域资源、经济、环境的协调性一般。 相似文献
7.
中国水资源与经济发展要素的时空匹配分析 总被引：4，自引：1，他引：4
水资源相对短缺已经成为影响区域社会、经济和生态可持续发展的重要因素。本文以2004年-2009年我国31个省市水资源分布、水资源配置相关数据为基础,计算各地区水资源与人口、面积、GDP等经济发展要素的基尼系数,对我国水资源分布、配置与经济发展要素匹配关系的时间演变规律进行研究。结果表明：我国水资源分布与人口、GDP的匹配关系处于波动均衡状态,而与土地面积之间处于极不匹配状态;水资源配置与GDP、人口、土地面积分别表现为比较匹配、不匹配和极不匹配关系,且不匹配程度有缓慢加剧的趋势。另一方面,按照空间维度分析需要,将全国划分为七大地区,并以2009年为例,计算了各地区水资源一经济发展要素的不平衡指数,借此阐释水资源分布、配置与经济发展要素在空间维度上的协调规律,找出主要影响地区。最后,提出了相应的调整措施,以期为缓解区域水资源短缺、调节水资源分布和配置的失衡提供依据。 相似文献
8.
中国北方地区主要树木的气候生产利研究 总被引：2，自引：0，他引：2
水资源短缺严重制约了华北高产粮区农业的可持续发展。本文对华北地区农业可持续发展的水问题况进行了阐述，对华北高产粮区的典型区域山东省桓台县农用水资源利用现状进行了分析，指出水资源浪费、污染严重，水资源管理不善是水资源利用过程中存在的最主要问题。并在区域、农 中国北方地区；树木；气候生产力 相似文献
9.
暴雨径流资源的调控－以吉林省西部为例 总被引：4，自引：0，他引：4
在我国广大兰干旱地区,一方面降水量少,水资源短缺;另一方面,降水又集中在7、8月,且多以暴雨形式出现,给农业生产带来严重危害。探讨暴雨径流资源的合理调控,有助于变灾害性的暴雨径流为宝贵的水资源,对实现农业可持续发展有着十分重大的意义。本文以吉林省西部为例,在分析水资源概况及其在利用上存在的问题和暴雨的地域分异,及划分暴雨径流资源调控区的基础上,对如何实施吉林省西部暴雨径流资源的调控进行了探讨。文中的调控措施可为其它半干旱区暴雨径流资源的调控提供借鉴。 相似文献
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11.
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
12.
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
13.
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
14.
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
15.
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
16.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
17.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
18.
《中国科学院院刊(英文版)》2014,(3)
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence 相似文献
19.
Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels 总被引：1，自引：0，他引：1
《中国科学院院刊(英文版)》2014,(3):267-268
<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese 相似文献
20.
WANG Sijia 《中国科学院院刊(英文版)》2014,(2):192-194
<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages. 相似文献