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1.
青海省冷凉气候资源分区及其开发利用 总被引：6，自引：1，他引：6
选用最热月（7月）和最冷月（1月）的平均气温作为划分气候大区的一级指标，最冷月的温度指标可分为冬冷（－20℃～－5℃）和冬寒（≤－20℃）两种类型，最热月的温度指标可分为夏热（≥20℃）、温（15℃～20℃）及夏凉（5℃～15℃）3种类型。根据青海青海省温度出现的范围，把青海省划分为冷凉和冷温2个气候大区；再以年≥0℃的积温、年干燥度(年最大可能蒸散量(E)与年降水量(R)的比值)作为二级指标，并结合各地区的自然景观又划分为11个气候区, 得出气候类型分区图。为合理地利用这种青藏高原特色的气候资源，针对各气候类型区的地理条件、自然灾害和气候资源的分布特征，评价了各气候分区适宜从事的农、牧业生产活动，提出了相应的资源开发利用对策。可为青海省加快农牧业生产结构战略性调整、发展特色农牧业经济、提高农牧业生产效益等方面提供科技支撑。 相似文献
2.
安娜 《内蒙古科技与经济》2019,(7)
利用赤峰地区14个气象站1961年～2017年逐日气温、≥10℃活动积温资料,分析了赤峰地区年平均气温、≥10℃活动积温、无霜期日数变化趋势,依据无霜期日数与≥10℃活动积温建立气候种植区划模型。结果表明:近57年来赤峰地区平均气温升高了1.31℃,≥10℃活动积温升高了218.31℃,无霜期延长28d,这是全球气候变暖的区域响应所致。赤峰地区荞麦种植可以划分为低产区、中产区、高产区3个种植气候区,低产区和中产区主要以牧业为主,种植业所占比例较小,荞麦种植区域主要集中在高产区。 相似文献
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以最热月和最冷月平均气温为主要指标划分，青海省绝大部分地区属冷凉气候；结构年≥0℃的只温，年干燥度等辅助指标，进一步细化分类，可将冷凉气候划分为7个类区。根据各气候类区的气候特征，提出了开发利用的主要途径，为促进西部大开发，加快青海省农牧业生产结构战略性调整的步伐，发展特色农牧业经济，提高农牧业生产的效益等方面提供科学依据。 相似文献
5.
气候变暖对山东省农业的影响 总被引：16，自引：3，他引：16
选取山东省资料年代较长的86个地面测站1961年～2004年日平均气温、最高和最低资料，计算历年日平均气温≥0℃、≥10℃积温和<0℃负积温，以及无霜冻终、初日变化，深人研究山东省热量资源对气候变暖的响应及其对农业生产的影响。结果表明：1987年～2004年比1961年～1986年的平均气温明显增高，尤以最低气温增幅最大，这说明最低气温的变化比最高气温的变化更敏感，山东省气候变暖主要来自最低气温升高的贡献；冬季升温幅度大于夏季，日平均气温≥0℃、≥10℃积温增多，无霜冻终日提前、初日推后，无霜冻期天数增多，<0℃负积温绝对值明显减少。山东省20世纪80年代后期气候明显变暖，热量资源增加，对冬季大棚蔬菜等设施农业的生产有利，喜温作物面积扩大，复种指数提高；同时，干旱发生的机率加大，病虫等越冬存活率上升，防止难度加大。气候变暖对山东省农业影响是利弊并存。 相似文献
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《内蒙古科技与经济》2021,(7)
利用1961年～2019年赤峰地区10个旗县区10个国家气象站逐日气温、降水量、日照时数等气象要素资料,统计分析了该地区近59年农业气候资源变化分布规律。结果表明,赤峰地区光能资源丰富,年太阳总辐射5 650MJ/m~2～5 830MJ/m~2,年日照时数2 800h～3 100h;热量资源充足,年≥10℃积温2 300℃～3 250℃,适宜发展农牧业;降水资源不足,年降水量330mm～460mm,并且变率较大,因此降水是限制赤峰地区农牧业发展的主要因子。 相似文献
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苏州热制课题研究协作组 《资源科学》1987,9(4):45-50
苏州市地处长江下游,太湖之滨。全年无霜期220—240d,0℃以上作物可能生长期338—350d,大于0℃的年积温约为5782℃,10℃以上喜温作物生长期229—234d,其间活动积温4850—5050℃。全年总日照约2000h,年降水量约1100mm。气候资源丰富,适宜种植稻、麦、棉、油等多种作物。 在种植制度上,苏州市历来以稻—麦两熟为主。1970年以后大面积推广双季稻、三熟制, 相似文献
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中国小流域径流对气候变化的敏感性分析 总被引：16，自引：0，他引：16
全球变暖导致的水文水资源问题越来越突出。为了预测气候变化对径流水资源的影响,本文利用全国469个小流域20多年年平均降水量、年平均气温和年平均径流量数据,细分不同的气候情景,分析径流变化对气候变化的响应程度。结果表明：一般来说,径流与降水变化趋势一致,与气温变化趋势相反,但是在局部地区由于温度的升高增加的降水超过蒸发的影响,径流随着气温升高反而增加;干旱地区径流对气温比对降水的响应更加显著,而在湿润地区径流对降水比对气温的响应更加显著;其中年平均气温11℃－15℃、年降水量400 mm---800 mm的华北地区,年均径流深对年均降水量的响应最敏感,而年平均气温低于5℃、年降水量低于400 mm的内蒙古高原西部及新疆北部的天山和阿尔泰山迎风坡低山地带,年均径流深对降水的响应最小;年均降水量200 mm ---400 mm、年平均气温6℃---10℃的内蒙古高原东部,气温对径流的影响最明显,而年平均气温16℃---25℃,年平均降水量800 mm---1600 mm的长江中下游地区、西南的大部分地区以及华东华南的大部分地区,径流对气温的响应相对不显著。 相似文献
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属珠江水系的广西红水河流域,位于北纬22°52′—25°37′、东经106°12′—110°23′之间,地处两个过渡带:一是由云贵高原的东南缘向华南沿海丘陵过渡,二是从中亚热带向南亚热带过渡,为亚热带季风湿润、半湿润气候区。热量丰富,降水较充沛,光、温、水基本配合较好,年平均气温16.8—21.6℃,≥10℃年积温为4978—7843℃,持续期长达252—328d,最冷月(1月)均温7.6—12.3℃,最热月(7月)均温27.4—33.2℃,极端最低气温只有-3.3—-5.5℃; 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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《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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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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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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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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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