生态与经济协调目标下的郑州市土地利用空间优化配置

城镇化快速发展进程中建设用地占用生态用地的现象普遍存在,如何协调经济发展与生态保护之间的矛盾成为目前中国土地利用所面临的主要难题。本文以郑州市为例,借助LANDSCAPE模型,开展生态与经济协调目标下土地利用空间优化配置。结果表明：①在满足耕地保护和建设用地需求的前提下,以2008年为基期,模拟2020年土地利用布局时,优化情景下比规划情景下土地利用空间布局的生态效益和经济效益分别提高0.3亿元和49亿元,实现经济发展和生态保护相协调。②两种情景下的模拟结果显示,建设用地配置向经济发展较快、生态效益较低的区域聚集。其中,优化情景下建设用地配置较多的区县为荥阳市、新密市及登封市;规划情景下建设用地配置较多的区县为金水区、惠济区、中牟县。优化情景下的建设用地布局更符合目前郑州市经济发展走向,对区域生态保护更为有利。③LANDSCAPE模型在一定程度上可解决传统的城乡建设用地指标分配方法对土地利用生态效益与经济效益的空间异质性考虑不够等问题,进而实现区域经济效益与生态保护的协调发展。     

福建晋江市农村城镇化进程中的土地利用变化分析

"晋江模式"是我国典型的农村城市化模式之一.该文基于TM遥感图像解译的1985年和2000年两期土地利用现状图,借助ArcGIS 8.2软件和统计分析技术,提取晋江市土地利用变化信息,并结合采用1990年、1995年～2001年土地利用变更资料和相应的社会经济统计资料,分析了以乡镇企业发展和农村剩余劳动力转移为主要动力的"自生"式农村城市化进程中的土地利用变化.结果表明:土地利用总量结构变化显著,土地利用方式呈现多元化态势,非农建设用地扩展迅速并呈大分散小集聚的空间均衡布局,建设用地及农用地的利用效率得到提高;培育中心城市、加强城镇体系规划,促使工业向园区集中,加快土地流转以提高耕地经营规模等,应是该模式下土地可持续利用的积极措施.     

长三角地区土地利用功能权衡的空间特征及其影响机制

经济发达区资源环境优化配置与国土空间质量提升是可持续发展领域关注的热点问题。科学认知不同类型土地利用功能间权衡关系及其空间特征、形成机制,有效调控和管理多种土地利用功能,是实现区域可持续发展目标的重要途径。本文以长三角地区为例,构建土地利用功能分类框架与评价指标体系,集成多源遥感、土地利用和社会经济统计等数据,利用InVEST、RUSLE以及均方根误差、地理探测器等模型方法,基于县域尺度定量评估区域各项土地利用功能,重点分析不同功能间权衡关系及其空间特征、影响机制,划定土地利用功能分区,探寻差别化土地利用功能调控路径。研究发现：①长三角地区农业生产功能与非农生产、生活保障2项功能权衡高值区主要分布在上海、苏州、无锡等沿江平原区,生态服务功能与农业生产、非农生产、生活保障3项功能权衡高值区主要分布在浙江和安徽两省的西南部等山地丘陵区;②土地垦殖率和年平均降水量、坡度等自然环境条件对农业生产功能影响较大,城镇化率是非农生产、生活保障2项功能的最主要影响因子,自然环境条件和土地利用结构均对生态服务功能具有较高影响;③长三角地区可划分为弱功能区、单一功能区、双功能共生区、多功能共生区4种类型分区,不同分区土地利用功能特征差异明显,据此提出差异化分区调控策略。本文结论有助于强化对土地科学研究领域的认知,支撑国土空间规划与管理决策。     

黄河流域土地利用时空格局演变及驱动力

土地利用时空格局是人类与自然相互作用状况的重要表征。研究黄河流域土地利用时空格局及其驱动因素,厘清土地利用类型转换及粮食保障用地、生态保育用地、城乡建设用地的时空变化特征,可为黄河流域生态保护和高质量发展国家重大战略的规划制定与实施提供参考。本文基于土地利用类型转移矩阵和空间自相关,从城市群、省、市、县多尺度入手,利用7期土地利用数据对黄河流域1970—2015年土地利用状况及变化进行探究。结果表明：①黄河流域生态保育用地和耕地占比多年平均值分别为79.04%和18.64%,表明生态保护和粮食生产是其两大主体功能;②城乡建设用地占比逐年提高,城市群地区是建设用地扩张的主体空间;③黄河流域耕地、生态保育用地和城乡建设用地各节点年份Moran’s I均大于0.75,表明3种功能类型用地具有强空间正向集聚效应,呈现出“凹”字型分布格局;④城乡建设用地扩张以牺牲耕地为代价,同时部分农村居民点用地逐渐转化为城镇用地;⑤人口规模和经济发展是促进土地利用变化的核心因素,驱动力因素存在区域差异,在黄河下游的山东、河南,经济水平达到一定规模后,伴随经济再发展不会出现大规模城乡建设用地扩张。     

1980年至2000年胶州湾地区土地利用变化及其对区域可持续发展的影响

胶州湾以其独特的环境特征与自然属性为周边地区提供了发展的优越条件,但其有限的土地资源和发展空间也成为区域可持续发展的制约务件.研究胶州湾地区1980年～2000年近20年以来的土地利用变化特征并分析其对区域可持续发展的影响,对区域未来发展有较强现实意义.研究表明:①1980年～1995年,该地区土地利用类型变化的主要特征是耕地绝对数量减少,城乡建设用地等其他土地利用类型绝对数量增加,耕地主要向城乡建设用地和牧草地等转换;1995年～2000年,土地利用类型变化的主要特征是城乡建设用地大幅增长,耕地少量增加,其它土地利用类型都在减少,其中牧草地减少最多;②其土地利用变化对区域可持续发展的影响可以从对粮食安全、生态环境以及社会经济发展的影响等方面反映出来.今后需要进一步探索可持续发展的土地利用模式,最终实档现社会经济与生态环境双赢的区域可持续发展.     

生产性服务业集聚与区域空间结构重构的作用路径分析

随着我国的经济形态逐步由商品生产迈向服务生产,高速发展的生产性服务业对于经济社会发展的支撑和推动作用日益彰显,生产性服务业在产业融合、吸纳就业、稳定增长等方面发挥重要作用,已经成为我国产业竞争的战略制高点及产业结构不断优化调整的关键力量。生产性服务业集聚集群对于区域经济发展及地理空间的演变发挥着巨大作用,生产性服务业集聚效应带来产业空间布局的重构及区域产业结构重组、价值链重序与附加值提升、促使城市空间格局的配套完善及其衍生发展、城市土地利用类型的变更及核心功能区格局的转移,生产性服务业的高速发展及集聚集群已经成为区域经济空间重构战略实现的驱动力。     

区域建设用地集约利用综合评价——以江苏省为例

在前人研究的基础上，从土地经济效率和社会效率等方面出发，构建了区域土地集约利用综合评价体系，结合江苏省实际情况，对江苏全省及65个县市区的土地集约利用水平进行综合评价研究，并指出其区域差异和变化趋势，提出提高土地集约利用水平的政策建议。研究结果表明：①江苏省建设用地集约利用水平整体从粗放扩张向集约利用转变；②江苏省虽然整体处于全国和东部地区前列，但与上海等省(市)相比建设用地集约利用水平还有一定的提升空间；③苏南、苏中和苏北地区建设用地集约利用水平差距显著；在经济发展水平相似地区内，不同县市区建设用地集约利用水平的差距也十分明显。文章指出，针对不同类型地区的经济发展规律和用地特征，设计区别性的用地政策，能够从宏观上指导不同类型地区的用地方向，避免低水平重复建设，提高土地利用集约程度，促进社会和谐发展。     

海南土地利用结构与产业发展关系研究

本文从用地-产出的角度研究土地利用结构与产业发展关系.综合前人研究,结合海南土地利用现状,构建一个基于产业的土地利用分类.采用1995年-2006年海南省的时间序列数据及其18个市县的面板数据,以数量经济模型为分析工具,利用线性回归模型、混合回归模型和个体效应模型,F统计量和H统计量进行统计检验等方法研究土地利用结构和产业发展之间的关系.研究结论为:①产业结构的变化影响产业用地结构,而且产业结构的变化快于产业用地结构的变化;②产业用地结构由产业规模与产业耗地技术水平以及自然环境约束共同决定.研究最后指出,产业生产技术水平及其耗地技术水平的提高是实现产业结构和土地利用结构双优化,推动经济发展的重要手段,同时区域自身的环境因素影响也应受到重视.     

长江中游经济带主体功能区土地利用转型模式研究

在国家深入推进生态文明建设和实施主体功能区战略的背景下,区域土地利用转型模式设计对缓解快速城镇化过程中社会经济发展与土地利用之间的矛盾具有重要意义。本文选取长江中游经济带为研究区,以325个县（区）作为基本研究单元,采用遥感和社会经济等数据,从土地利用形态（显性/隐性）转换的视角构建以耕地、建设用地和林地为典型地类的转型模式要素体系,并在此基础上解析新时期新目标对土地利用转型的要求,甄别不同类型土地利用转型方向,进而遵循可持续发展和主导性原则,总结归纳不同主体功能区土地利用转型模式。研究结果表明：长江中游经济带城市化地区土地利用转型模式包括规模与产出能力适度提升型（D_u+R_u+主导型）、规模控制而产出能力适度提升型（D_uR_u+主导型）等四种;农产品主产区转型模式包括规模和产出能力稳定型（D_cR_c主导型）、规模稳定而产出能力提升型（D_cR_c+主导型）等四种;重点生态功能区转型模式包括规模增加型（D_f+主导型）和规模稳定型（D_f主导型）两种。模式研究有望能为进一步推动长江中游经济带各主体功能区城乡融合发展和促进各县（区）土地可持续利用提供参考。     

简论生态农业与不发达地区农村经济发展

不发达地区农村经济发展应遵循一种什么模式,本文试图提出自己的看法。一改革开放以来,东部地区出现了众多的农村经济发展模式,苏南模式、温州模式、佛山道路等,都是大家十分熟悉的。它们的共同点是通过发展非农产业来促进农村经济发展。从理论上说,经济发展必然出现结构变革,表现出农业份额下降的趋势。因此,这些模式是符合一般经济发展规模的。发达地区走非农产业道路的条件是;①农业本身有了一定程度的发展;②历史上就有经商传统,人们商品意识浓厚;③具有各种非农技术;④资金较充足。     

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）.