共查询到20条相似文献，搜索用时 62 毫秒
1.
旱地在我国南方山区占据相当大的面积,约占其耕地总面积的40％左右。主要分布于川、滇、黔、鄂、湘、赣、浙、闽等省及桂北、粤北、皖中南等亚热带丘陵山区,约占南方旱地总面积的90％。其中川、滇、黔、鄂四省旱地面积最大,约占耕地面积的50—65％,有些山区县和区乡的旱地面积占其耕地面积的75—95％。但目前旱地农业不大引人重视,生产水平很低,低产旱地约占3/4以上,旱粮产量仅占粮食产量的10—25％,特别是旱地作物单产水平远低于水田,旱粮平均亩产只有200—300斤,其中小麦、大豆单产更低,不到100斤;旱地油料作物平均亩产只有30—50斤,麻类作物100—200斤,烤烟200斤,棉花只20—30斤,甘蔗2000—3000斤,一般要比水田作物产量低1—3倍。研究南方山区旱地农业特点、充分合理利用旱地资源、挖掘旱地农业的生产潜力,对我国南方山区农业的发展,搞活山区农村经济具有重大的战略意义。 相似文献
2.
浙中山区旱地春玉米的栽培措施 总被引：1，自引：0，他引：1
根据浙中山区自然条件和种植制度的现状 ,为提高粮食产量 ,进一步发展“一优两高”农业 ,磐安县总结了多年来春玉米生产的实践经验 ,证明了利用上半年雨量充沛、温度适宜的气候优势 ,改夏秋玉米为春玉米是发展旱地持续农业的成功之路 .文章剖析了以春玉米为主的高产、高效种植结构及其经济效益和现有生产水平下的配套栽培技术 ,并提出了改制增熟、间作套种和开发特种玉米的发展途径 ,为相邻地区旱粮生产的发展提供了依据 相似文献
3.
根据浙中山区自然条件和种植制度的现状,为提高粮食产量,进一步发展“一优两高”农业,磐安县总结了多年来春玉米生产的实践经验,证明了利用上半年雨量充沛,温度适宜的气候优势,改夏秋玉米为春玉米是发展旱地持续农业的成功之路。文章剖析了以春玉米为主的高产,高效种植结构及其经济效益和现有生产水平下的配套栽培技术,并提出了改制增熟,间作套种和开发特种玉米的发展途径,为相邻地区旱粮生产的发展提供了依据。 相似文献
4.
要在发展粮食生产的基础上,通过粮食作物(粮、饲)结构和养殖业结构的调整和优化,发展饲料加工业,开拓粮食与非粮食、耕地与非耕地等多种途径发展饲料生产,要树立大粮食观念,挖掘旱粮增产潜力。为了适应迅速发展的饲料加工业和畜禽规模经营,在旱粮相对集中的产区建立商品饲料生产基地。从面积和单产两个方面,进行早粮生产的广度和深度开发,提高精饲料玉米等的自给率,增加饲料总量。 相似文献
5.
钱光荣 《大科技．科学之谜》2014,(6):262-263
本文首先对免耕的概念进行了解释,并对目前山区农村旱地在种植方面存在的问题进行了分析,阐述了在山区农村旱地推广免耕种植技术的意义。随着市场经济的发展,农村也在不断地进行改革,旱地种植结构的矛盾越来越突出,粮食种植效益也越来越低,普遍存在粮食增产不增收的现象。针对此类现象,对旱地种植结构进行优化,才能促进农业效益的发展。 相似文献
6.
宁夏南部山区特色小杂粮资源利用与可持续发展战略研究 总被引：2，自引：0，他引：2
小杂粮是宁夏南部山区的优势资源。积极发展特色杂粮产业对于调整优化该地区种植结构。切实保护和提高粮食生产能力，促进贫困山区生态经济协调可持续发展有着重要的意义。本文通过对宁南山区旱地特色小杂粮生产现状及发展优势的分析，提出了以发展优质高产高效旱作农业为出发点，以建立适应不同降水条件的主要作物优化栽培模式为核心，以高效利用天然降水和提高养分利用率为突破口，促进宁南山区旱地特色小杂粮资源利用和可持续发展的措施与途径。 相似文献
7.
8.
玉米经济效益系统剖析 总被引：1，自引：0，他引：1
玉米是一种高产作物,又是饲料之王。目前,我国农业正在向种养加、粮牧企的深层次发展,其重要因素也将取决于玉米生产的发展程度。探讨了玉米在兴牧增值、膳食改善、培育地力、粮食增产中的重要地位。 相似文献
9.
由浙江省科委、省农业厅和浙江农业大学联合召开的省首次生态农业典型经验交流会最近在德清县举行。会议收到几十篇论文,有各地不同生态模式的典型总结,也有专题研究报告和学术论文。会议认为,浙江省是国内最早实现粮食亩产八百斤、超千斤的省,既有生态农业的优良传统,又有建国三十多年来组织社会主义农业生产的丰富经验。杭嘉湖地区的“粮、桑、渔、畜”结构便是我国传统生态农业的杰出代表之一。在农业现代化、商品化过程中如何改革本地区的农村产业结构,创造出山清、水秀、土肥、人富、生产发展、环境不污染、高节奏、高效率并保持良好生态环境的前进代农业模式,无疑将有导向性作用。农大、德清县代表在会上汇报了三年来“杭嘉湖平原生态农业研究”工作情况,对干山乡基点的生态实 相似文献
10.
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