新农村建设中的农村土地整治——以宁远县为例

农村土地整治是一项一举多得、利民利乡利城的好事。近年来,我国以改善农村生产生活条件、促进城乡统筹发展为出发点,以保护耕地、建设新农村为目标,深度整合土地资源,优化土地利用结构,提高土地利用效率,促进土地节约集约利用,探索了一条城乡统筹发展的新途径,加快了城乡一体化发展,有力推动了社会主义新农村建设。     

土地利用冲突的理论与诊断方法

随着社会经济的发展,土地资源日趋紧张,土地利用冲突发生的频率、涉及的层面、冲突的内容以及冲突所引发的后果都越来越多,诱发土地利用冲突的因素也越来越复杂。因此,开展土地利用冲突研究,科学评价区域土地利用冲突的强度,进一步揭示土地利用冲突的外在表现形态及其产生冲突的内在机理,是解决区域土地可持续利用中存在的种种不和谐问题的关键所在。论文通过对国内外文献的归纳和梳理,完善了土地利用冲突研究的理论框架和土地利用冲突研究的主要内容,构建土地利用冲突强度的诊断模型和方法,并提出未来土地利用冲突的重点研究领域。其目的是提高土地要素的空间配置效率,缓解土地资源压力,促进我国土地资源空间结构向良性方向演进,实现土地利用的综合协调管理。     

江苏省土地利用变化及其旅游驱动力研究

利用江苏省1996年-2008年土地利用变更调查数据,分别从土地利用数量、土地利用结构、土地利用程度三方面分析了江苏省土地利用变化特征,结果表明,近10年来,江苏省耕地、牧草地明显减少,交通用地与居民点及工矿用地迅速增加;土地利用结构信息熵与均衡度总体呈增长态势,用地结构不断趋于均质化;土地利用程度不断增强,用地效率明显提高。结合研究区实际情况,选取旅游总收入作为LUCC变化的旅游驱动因子,借助线性回归分析方法,建立江苏省主要土地利用类型的旅游驱动力模型,结果表明,江苏省旅游经济发展对其土地利用变化具有显著影响。建议制定有关土地利用政策时,应充分考虑影响土地利用变化的旅游驱动力因子,以更好促进区域土地资源的可持续利用。     

海南城乡土地利用差异及其优化策略探讨

土地利用是影响城乡关系的一个重要因素,从优化城乡土地利用和土地资源管理的角度,探讨统筹城乡发展的途径具有重要的现实意义。基于对海南省土地利用现状的分析,揭示出城乡土地利用中存在的突出问题,以及城乡土地利用效率的区域差异特征。提出海南省促进城乡协调发展的土地利用优化与管理创新策略是:①适应社会经济发展趋势,革新理念和管理体制,探索推进城乡协调发展的土地资源管理创新途径;②通过完善土地市场配置机制,确立农民作为土地产权的主体身份,保证农民土地交易和经营的合法利益,提升农村生产力;③政府应通过加大农村土地整理力度,扶持农村发展与新农村建设,促进城乡经济发展。     

江西上饶县农业产业结构调整与土地利用变化研究

文章在分析区域农业产业结构调整与土地利用变化的相互作用机理的基础上,以江西省上饶县为例,分析了研究区域土地利用结构的多样化和集中化趋势,并着重通过构建土地类型之间的转移矩阵和农地利用变化强度驱动因素的指标体系,研究了江西省上饶县农业产业结构调整下土地利用变化的基本特征.结果表明:①由于农产品价格变化所导致的农业产业结构调整,是近年来上饶县土地利用变化的主要驱动力;②农业产业结构调整与土地利用变化之间存在明显的阶段一致性特征;③不同产值经济结构的差异性,使得农户对农业产业结构调整的力度存在差异,从而使得区域内部土地利用变化的程度也不一致;④上饶县土地利用动态变化总体上具有农业型特点.由于在市场规律的作用下,单位土地面积的收益差距明显增大,导致农业内部耕地、园地、林地和水域之间的相互转换;同时,由于农村工业化和城镇化的发展,使得农用地尤其是耕地(水田)面积不断减少,农用地向建设用地转化.据此,作者提出了土地资源可持续利用的政策建议.     

浅析3S技术在土地利用卫片执法检查工作中的应用

城市建设过程中土地资源是重要的一环,在土地市场不断发展的同时,土地资源各类违法现象越来越严重,为了保护耕地资源和有效遏制各类违法行为,就必须在新时期加强土地利用执法检查工作,以崭新的技术手段应用来提高土地资源利用执法检查的工作质量和效率。3S技术是当前土地利用检查工作重点应用的技术途径,本研究根据3S技术的特点,结合土地利用执法检查工作的实际,提出了3S技术在土地利用卫片执法检查工作的具体应用。     

基于CLUE-S模型框架的土地可持续利用情景预测——以阳泉市郊区为例

土地持续利用是区域可持续发展的核心内容与重要基础,提高土地利用效率、优化土地资源配置是推动区域经济可持续发展的必要手段。土地利用规划在推动土地资源可持续利用方面发挥了重要作用。在现有土地利用数据的基础上,充分整合自然和社会因素的影响,全面考虑各土地利用类型的供需平衡关系,合理预测未来土地利用变化情景,特别是建立一个开放性的研究框架,是土地利用研究和规划实践中亟待解决的问题。本文以阳泉市郊区为例,提出简化的CLUE-S模型研究框架,探讨研究区不同发展路径下的土地利用变化情景,以期为土地利用规划提供决策依据。研究结果表明,在土地利用规划中,耕地优先原则、生态保护原则、效益提高原则依次为发展路径的先后选择顺序。较＂生态涵养＂及＂超速掠夺＂路径,＂均衡发展＂路径安排耕地18131.57hm2,安排建设用地14069.40hm2,可以满足阳泉市郊区在未来15年内粮食自给率上升27个百分点,国内生产总值年均增幅达到13%的用地需求,为最适宜发展情景。     

广西北部湾经济区土地利用变化分析

广西北部湾经济区的开放开发,不可避免地伴生着土地资源的利用,如何合理高效地利用土地资源成为了当前该区域研究的热点议题。文章科学地分析并定量识别土地利用的演变,对于提高广西北部湾经济区土地利用效率水平,促进区域的可持续发展有着重要的意义。选取广西北部湾经济区2008年、2012年、2016年三期Landsat7 TM、Landsat8 TM遥感影像作为遥感解译的基础数据,运用探索性空间数据分析(ESDA)方法,从结构变化、数量变化、程度变化、速率变化、转移变化等五方面对广西北部湾经济区整体的土地利用时空演变格局进行分析。结果表明,广西北部湾经济区土地利用存在以下问题:(1)人均耕地少、土地集约利用水平低;(2)土地利用区域性差异大;(3)建设用地占用耕地比例过大;(4)建设用地扩张速度过快。     

土地细碎化、土地流转对农户土地利用效率的影响

尽管中国实行了世界上最严格的耕地保护制度,但耕地数量仍不断减少,并将在今后一段时间内呈减少趋势,在一定程度上威胁了我国的粮食安全。提高土地利用效率是保障我国粮食安全的一条重要途径。本文选取耕地复种指数和土地综合产出率两个指标来表示农户土地利用效率,利用江苏省南京市274个农户的实地调查数据,运用多元线性回归模型对土地细碎化、农地流转对农户土地利用效率的影响进行了实证研究。模型估算结果表明：土地细碎化导致农户复种指数的下降,并阻碍了平均土地综合产出率的提高;转出土地的农户的复种指数和平均土地综合产出率要低于没有转出土地的农户,而转入土地农户的平均土地综合产出率要高于没有转入土地的农户。因此,建议通过推进土地流转来提高土地利用效率。     

雄安新区土地利用空间特征及起步区方案比选研究

雄安新区是千年大计、国家大事。深入分析雄安新区土地利用的现状空间特征,对于推进新区高起点高标准规划建设具有重要意义。本文基于多时相Landsat-TM/ETM+/OLI遥感数据解译,分析了雄安新区土地利用的总体特征,并重点研究了建设用地节约集约利用的潜力和耕地质量的区域差异。提出了雄安新区起步区的三个可能备选方案,并分析了其各自利弊。研究表明,雄安新区土地呈"六田、二建、一水、半分林"特征;现状建设用地尤其是农村建设用地的节约、集约利用潜力较大;耕地质量及其利用强度的空间差异显著,容城、安新耕地质量好,复种指数高,分别达1.92和1.87,雄县耕地质量较差,复种指数明显偏低,仅为1.32。综合考虑起步区的相对完整性、未来发展的可拓展性、与周边县市的兼顾性和防洪安全性,统筹权衡优质耕地保护和建设用地征收拆迁成本等因素,本文建议以位于容城东部与安新、雄县交接处的"中方案"作为起步区的优先方案。针对新区建设需要大量占用土地的现实需求,本文建议优先通过农村(含乡镇)集体建设用地的征收与节约集约利用解决;新区建设不可避免会占用耕地,建议优先安排占用等级较低的耕地,尽量保护优质高产耕地;建议合理确定土地征收与征用时序,分类施策,优化土地资源管控。同时指出,雄安新区大部分地势相对较低,新区规划、选址和建设需要高度关注防洪排水问题。     

To serve and promote science development via innovation

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.     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

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.     

Tracing the origin and early radiation of birds——Paleornithologist ZHOU Zhonghe

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."     

Cooler temperatures inductive to locust outbreaks

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.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

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.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

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.     

Prevalence of soft neurological signs in Chinese people

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.     

Stern-Gerlach effect goes chiral

Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms＇ spin states （Phys. Rev. Lett. 99 130403）.