干旱区植物群落“岛屿化”成因浅析

植物群落的"岛屿化"是指由于环境条件的变化,原来成片的植物群落自动疏离成小植物群落或群丛,而中间则被裸地所隔离,形成"岛屿",从连片植物群落到"岛屿"的形成过程则称为"岛屿化"。本文针对植物群落的"岛屿化"的原因,过程,发展及维持机制作出全面的分析。     

“最顶级奢侈品”购买攻略——私人岛屿不是梦

经济的衰退不一定意味着购买力的削弱。长达12733公里中国岛岸线，大大小小1万多个无人岛屿，正等待成为中国富翁攻城略地的下一个目标。私人岛屿不是梦——实现岛主之梦，你准备好了吗？     

“莲花洋人”朱仁民：视岛如命

画家朱仁民买下莲花岛是在1996年，比国家正式发文允许私人开发岛屿早了7年。当国家海洋局的“海十条”发布之际，他已经对小岛投入了至少3000万元资金和13年光阴。很多人会把岛屿出作财富，朱仁民的莲花岛入口却有这样一块牌子：永久免费参观。     

小岛攻防：透视我国可能面临的小岛争夺战

笔者曾在《艰巨的作战》一文（见《舰载武器》2008年第9期）中对岛屿登陆作战作了一些探讨，但主要是从大型岛屿登陆作战角度进行的，对小型岛屿攻防作战基本没有涉及。本文可以说是《艰巨的作战》一文的姊妹篇，主要论述我国未来可能被迫进行的小型岛屿攻防作战。     

塞浦路斯，走入希腊神话的度假天堂

塞浦路斯，一个充满神话色彩的岛屿，一个美得像从希腊神话故事中走出的岛屿，古老的人文古迹构成她独特的魅力，今天我们一起去目睹一下她的风采。[编者按]     

对岛屿封锁作战短波通信联络应解决的几个问题

对岛屿封锁作战短波通信联络十分复杂，对各种各样的复杂情况应如何处置，是确保对岛屿封锁作战指挥顺畅的基础和关键，是对岛屿封锁作战能否顺利实施的重要因素。为了提高对岛屿封锁作战短波通信联络的及时、可靠性，必须以对岛屿封锁作战和实战演练为背景，结合模拟战场环境，突出抗电磁干扰能力等方面下工夫。     

私人岛屿 不再是梦

拥有一座私人岛屿是很多人的梦想，而在早期这还只是文学作品中作者对生活的向往。一般人心里的岛屿生活，或隐居山林，或畅游海底，极尽享乐之能事，然而对于真正的岛主，拥有什么对于他们来说已经并不重要，重要的是如何享受岛屿给他们带来的精神满足。如今，一岛之主已不再是场遥不可及的梦。     

螺旋桨坐标制图法

本文对螺旋桨的制图，从应用几何原理转化为代数式的形式作了探讨，提出了采用坐标关系式和利用微机辅助计算绘制螺旋桨图的方法，由此可大大提高工作效率。     

海滨天堂

新喀里多尼亚（No11vlle—Caledonie）位于南太平洋的中心，在茫茫大海上伸展着它细长的身姿，这座世界尽头的岛屿，静静地躺在广阔无垠的蔚蓝海水之中。新喀里多尼亚拥有国土面积24000平方公里。这里有着长达1600公里珊瑚礁障，从北到南400千米，从西到东50千米。这里拥有人口约23万，他们分别生活在七个岛屿上。主要岛屿有新喀里多尼亚岛和洛亚蒂群岛等。     

私人岛屿生活：面朝大海，春暖花开

随着政策的放宽，私人拥有岛屿早已不是奢望，无论是政策环境还是个人的财力，在中国有实力拥有私人小岛的个人不在少数，然而这并不代表拥有私人岛屿就是一件轻松的事，除了要迎合当地政府的规划，还要考虑自然环境和岛上基础设施的建设，同时在开发方式上，内陆的湖岛江岛与海岛又完全不—样，前期成本相差巨大，后期维护费用也是天价数字。所以岛屿生活虽然美好，但在岛屿选择、购买和建设上无疑要慎之又慎。     

军事标图系统架构研究

军事标图系统是指挥自动化系统的一个重要组成部分。目前计算机军事标图系统已由单机作业逐步向分布式协同作业发展。研究单机军事标图系统的基本结构及其功能组成，提出一种集中式结构的分布协同标绘系统体系构架，并分析集中式结构存在的问题。实践应用表明具有较好效果。     

内河航道制图与电子航道图一体化生产

内河航道制图与S-57标准电子航道图数据一体化生产技术可以避免空间数据的重复建设,提升内河航道测量数据的应用价值.在剖析了制图数据和S-57标准电子航道图数据差异性的基础上,设计了内河航道制图与S-57标准电子航道图数据一体化生产流程,制定了空间数据生产规范,并采用北京清华山维公司的EPS平台,实现了内河航道制图与S-57标准电子航道图数据一体化生产技术.实践结果表明,该技术合理、实用、高效,可广泛应用于我国内河数字航道建设.     

Exploring the effects of passenger rail franchising in Britain: Evidence from the first two rounds of franchising (1997-2008)

This paper provides an up-to-date review of the previous literature concerning the impact of passenger rail franchising on productivity and costs in Britain, and also presents important new evidence. In particular, the extension in time of previously-used datasets offers the first opportunity to study the impacts of re-franchising. The previous literature emphasised the failure of franchising to produce sustained productivity gains, with a sharp deterioration in productivity after 2000. The new evidence presented offers a somewhat more positive view of the British experience. It suggests that part of what was previously considered to be falling productivity may in fact be due to exogenous changes in diesel prices. Further, new data suggests that the recent increases in costs have resulted in higher quality of service. Finally, competitive re-franchising, and the associated unwinding of short-term management and re-negotiated contracts, seems to have led to improvements in productivity between 2006 and 2008. Nevertheless, it remains the case that passenger rail franchising in Britain has failed to reduce costs in the way experienced in many other industries and in rail in other European countries. The evidence is that somewhat larger franchises, avoiding overlapping and optimising train density and length, should reduce costs. We also speculate that the major increase in wages and conditions of staff might be moderated by longer franchises, although that remains to be proved. This re-appraisal of the British case is important in the context of the wider international interest in the use of franchising in passenger rail, and its relevance to the current review of ways of introducing competition into the domestic rail passenger market in Europe.     

长江口南汇边滩短期冲淤变化分析

南汇边滩位于长江口和杭州湾的交汇地带,受长江口和杭州湾北岸两股潮流的控制,近年来由于低潮滩促淤围垦工程导致其水流和泥沙运移、沉积和地貌发生了显著的变化。根据2006—2008年南汇边滩测图及2007年11月—2008年11月每个季度的9个断面测量资料,结合区域内的泥沙沉积特征,探讨南汇边滩对周边涉水围垦工程和流域来水来沙变异做出适应性地貌耦合过程之后的近期冲淤演变规律,着重探讨季节性冲淤特征。结果表明:年度上南汇东滩以淤长为主,南汇南滩以冲刷为主。不同季节南汇边滩冲淤变化过程存在很大差异:平面上,南汇边滩等深线夏、冬季以淤进为主,春、秋季以蚀退为主;垂向上,南汇东滩断面呈春夏秋冲淤交替、冬季淤积的态势,南汇嘴断面呈秋季冲刷、冬夏季淤积的态势,而位于南汇南滩的断面则呈秋冬季冲刷、春夏季淤积态势。南汇东滩沉积物粒径总体上较细,东滩与南滩交汇处的南汇嘴附近中值粒径相对较粗,南汇南滩浅滩沉积物颗粒中值粒径最粗。     

无人船在港口水域海事监管中的应用探讨

近年来,随着与船舶自主航行相关的信息技术、人工智能技术水平的提高,无人船舶行业取得了长足的发展,其在海上安保、环境监测等领域应用也越来越成熟。为推动无人船在海事管理方面的应用研究,破解港口水域海事监管手段不足的瓶颈问题,文中在分析港口水域海事监管特点和无人船系统建设条件的基础上,定量研究了无人船在港口水域海事监管应用面临的性能指标确定、船型平台选择、载荷设备搭配、运行管理体系建设等方面的具体问题,提出了一种港口水域海事监管无人船系统的应用解决方案。     

Differences in emission of nitrogen and phosphorus into the Vistula and Oder basins in 1995-2008 — Natural and anthropogenic causes (MONERIS model)

The aim of the modeling studies (MONERIS) was to estimate annual source apportioned nitrogen (N) and phosphorus (P) emissions into the Vistula and Oder basins in 1995-2008, thus, during the transition period in Poland, characterized by changes in both agricultural sector and handling of point source pollution. N and P emissions into both basins showed declining tendencies. Between the sub-periods 1995-2002 and 2003-2008, the overall N emission into the Vistula and Oder basins decreased by 16-17% (i.e. by ca. 26,900 tons in the Vistula and by ca. 18,000 tons in the Oder basin); P emission declined by 23% in the Vistula and by 32% in the Oder basins (i.e. by ca. 3400 tons in the Vistula and by ca. 2200 tons in the Oder basin). The temporal patterns of N and P emission into the Vistula and Oder basins, as well as the percentage contribution of N and P pathways (particularly: overland flow, tile drainage, groundwater, waste water treatment plants) showed great differences between the basins. Natural (type of bedrock, soil type, lake area) and anthropogenic (regionally and temporarily different type and intensity of agricultural activity, spatially different structural changes in agriculture during the transition period, regionally and temporarily different investment in waste water treatment plans) factors were found to be responsible for the differences, and the relationships are extensively discussed in the paper. In 1995-2008, 70% of N emission into both river basins was via groundwater and tile drainage, with the former playing more important role in the Vistula basin, and the latter playing more important role in the Oder basin; contribution of N emission from point sources was comparable in both rivers and it reached 11-12%. In 1995-2008, point sources, erosion, overland flow, and urban systems were found the most important P pathways in both basins, with a higher percentage contribution of point sources in the Oder basin.     

航道护岸工程中基槽边坡稳定研究

航道护岸工程中经常发生基槽边坡滑坡失稳事故，从而造成经济和安全问题。因此，就滑坡发生机理进行研究对保障航道护岸工程顺利建设有重大意义。从极限平衡原理出发，分别运用Fellenius法和Bishop法验算了苏北某航道护岸工程开挖边坡的设计稳定性，并分析比较两种方法的差异，得出了在多层土的计算中有时会出现Fellenius法比Bishop法的安全系数略大的结论。结合工程实际中可能出现的渗流和超载等因素，计算得到边坡安全系数的变化规律和极限平衡状态时的临界负荷，从而提出了相应的预防渗流、控制超载等措施，可以为航道护岸建设提供参考。     

半刚性基层沥青铺面结构在集装箱港区道路中的应用

将半刚性基层沥青铺面结构应用于上海外高桥集装箱港区道路,在国内尚属首创。针对港区道路的特点,结合上海地区水文、地质和建材供应条件及港区生产使用功能要求,通过调查分析和总结集装箱港区已建类似工程道路铺面结构使用情况,分析论证相关施工技术方案,并进行必要的试验,对于半刚性基层沥青铺面结构在应用过程中遇到的各种技术问题,提出了较系统的处理办法。     

Intrusions of eastern North Atlantic central waters and phytoplankton in the north and northwestern Iberian shelf during spring

The influence of intrusions of eastern North Atlantic central water (ENACW) in the north and northwestern Iberian shelf on phytoplankton composition and abundance and on particle-size distributions of seston was analyzed using data collected on three extensive cruises during spring 1991 and 1992. Water with temperature and salinity values between 12.20 and 13.86 °C and between 35.66 and 35.98 psu, respectively, characteristics of the subtropical type of ENACW (ENACW_t), was detected in the upper 100 m of the water-column in all cruises, but particularly in the western coast in 1992. The highest salinity values of this water were found near the surface (0–100-m depth) and in early spring 1992, while minimum salinity values, and also minimum geographical extension, were found in late spring in both years. Phytoplankton blooms concentrated in frontal areas between different water types, with maximum intensity and extension in early spring.Using temperature and salinity characteristics, samples were classified in four groups corresponding to the major water types found in the region: Bay of Biscay central water (BBCW), two segments of ENACW of different salinity and surface water influenced by continental runoff. This classification was significantly confirmed by three independent discriminant analyses using hydrographic and chemical (dissolved nutrients and chlorophyll) variables, phytoplankton species abundance variables and particle-size concentration of seston variables. Phytoplankton blooms related to the presence of saline waters were characterized by the dominance of either chain-forming diatoms or a mixture of diatoms and phytoflagellates and high concentrations of seston. The diatom species dominating in saline waters were typical of upwelling-induced blooms occurring generally during summer. Blooms occurring in waters influenced by runoff also contained diatoms but in lower numbers than those of saline waters. Nutrients were not exhausted in the region, suggesting that phytoplankton populations were still in active growth. These results are interpreted taking into account the known variability in water-mass formation and in the poleward current driving ENACW_t along the shelf, and indicate that saline intrusions are a major feature affecting the distribution and composition of plankton in the spring in the southern Bay of Biscay, thus enlarging to a wider spatial scale their reported influence on the pelagic ecosystem.     

后张预应力空心板在港口工程中的应用

由于后张预应力空心板的体积较小、预制安装简单方便,有利于规模化生产、运输和安装,已广泛应用于我国公路桥梁工程的上部结构中.结合福建地区港口工程中以后张预应力空心板作为上部结构的实例,介绍后张预应力空心板的设计、预制和安装的要点,并针对施工期空心板加载试验数据进行分析,总结在港口工程中采用后张预应力空心板的经验,供类似工...