旅居者跨文化适应影响因素研究——以在华美国人为例

旅居及其引发的问题,以往主要属于社会学、心理学的研究范畴,但随着研究的不断深入,其展现出强烈的属于文化地理学研究范畴的特征与要素。运用结构方程模型、相关分析等方法,对美国来华旅居者的跨文化适应影响因素展开实证研究。研究结果表明:旅居时间与东道国文化认同之间的正相关性最大,旅居国数与一般生活满意度的正相关性最弱;提出的10个假设中,除了旅居国家数量对文化取向的变化没有显著影响关系外,其余9个假设都得到了证实。     

基于主客观生活质量评价的农村发展差异分析——以北京山区经济薄弱村为例

从居民生活质量角度评价区域发展程度长期以来备受关注。本文以北京山区经济薄弱村为例,在抽样农户调查基础上,基于小康监测体系中的生活质量指标体系,采用因子分析法构建的主观评价体系,分别测算了村级客观、主观生活质量指数,运用聚类法与差异贡献率法,开展北京山区经济薄弱村居民主客观生活质量的对比评价及影响因素分析。研究表明:1客观指数上,99.29%的村庄低于北京农村的平均水平,村间差异显著,高指数村庄主要分布在地势平坦的近郊区;2主观指数上,具有一定地域趋同性,离城区越近主观满意度越低;3综合来看,深山区与近郊区的村庄自身存在较大的主—客观差异,18.95%的村庄综合生活质量较差,文化娱乐、信息教育、生态环保等生活品质是限制居民生活质量的主要因素;4差异扶贫、提升人口综合素质、扶持生活质量高维度相关产业发展以及开展扶贫动态监测与开发规划,是进一步改善居民生活质量、提升区域发展水平的主要驱动力。主客观生活质量评价能够深入反映区域发展与居民生活质量间的关系,可作为区域综合发展决策的重要辅助方法。     

台湾海峡及其邻近海域鱼类生活史特征及其变化研究

世界范围内,海洋渔业资源广泛面临着过度捕捞的压力.鱼类的不同生活史特征可表征不同的生活史对策,其变化可揭示鱼类种群对渔业捕捞压力的响应.台湾海峡及其邻近海域的主要渔场30多年来面临着过度捕捞的压力,导致了鱼类群落结构发生改变.本研究分析了该海域51种主要经济鱼类的生态参数,系统研究了其生活史特征及其变化.采用主成分分析法可将51种鱼类分成5个不同的生活史对策组,分组结果表明超过60%的鱼类被归纳入第5组,即近r对策组,且多为中上层鱼类.在此基础上收集相关历史数据,对其中25种经济鱼类进行生活史变化分析,讨论不同鱼类种群对渔业开发的响应.分析结果表明,在长期的渔业开发活动下多数鱼类表现出小型化、低龄化、早熟和生长率加快等趋势.此外,本研究计算了每种鱼类的开发率以进一步研究渔业捕捞压力对鱼类种群的影响,发现其中4种底层和近底层鱼类的生活史特征变化显著,提示某些物种可能对捕捞压力更敏感.本研究可为渔业管理和保护提供重要的科学依据.     

主要环境因子对细弱蜈蚣藻(Grateloupia tenuis)孢子发育的影响及生活史的研究

在实验室条件下,以细弱蜈蚣藻(Grateloupia tenuis Wang et Luan)为材料,进行了不同温度和光照强度等主要环境因子对其发育影响的研究,同时对其生活史进行了详细观察。结果表明:(1)在4—30°C范围内,盘状体形成与直立枝生长的最适温度为24°C;(2)在光照强度10—200μmol范围内,盘状体形成和直立枝生长的最适光照强度为120μmol/(m2s);(3)孢子(果孢子和四分孢子)发育类型为间接盘状体类型;(4)生活史由单倍体的雌、雄配子体,双倍体的果孢子体(囊果)及四分孢子体构成,四分孢子体和配子体在形态上完全相同,属于典型的同型世代交替;与属模蜈蚣藻(G.filicina)一致。     

Biophysical models of larval dispersal in the Benguela Current ecosystem

We synthesise and update results from the suite of biophysical, larval-dispersal models developed in the Benguela Current ecosystem. Biophysical models of larval dispersal use outputs of physical hydrodynamic models as inputs to individual-based models in which biological processes acting during the larval life are included. In the Benguela, such models were first applied to simulate the dispersal of anchovy Engraulis encrasicolus and sardine Sardinops sagax ichthyoplankton, and more recently of the early life stages of chokka-squid Loligo reynaudii and Cape hakes Merluccius spp. We identify how the models have helped advance understanding of key processes for these species. We then discuss which aspects of the early life of marine species in the Benguela Current ecosystem are still not well understood and could benefit from new modelling studies.     

Raman spectroscopic and scanning electron microscopic analysis of a novel biological colonisation of volcanic rocks

A novel type of colonisation of a basaltic rock, collected on the Arctic island of Svalbard, Norway, during the AMASE expedition in 2004, was characterised using Raman spectroscopy and Scanning Electron Microscopy (SEM). The sample contains two different types of extremophile communities, one occurring behind a radial white crystallisation and the other occurring inside a dark vacuole. Several types of minerals and microbial colonies have been identified by both Raman spectroscopy and SEM analyses. It is the first time that photosynthetic communities have been documented to colonise the inside of dark basaltic rocks. Our discovery has important implications for planetary exploration because it extends the analytical capability and our understanding of microbial rock colonisations to subaerial volcanic outcrops and has wide implications towards the search for life in extraterrestrial planets. In this work we also demonstrate that the use of different laser wavelengths for Raman spectroscopic studies and complementary microscopic analysis are critical for a comprehensive organic and inorganic compound identification.     

鞘褶皱式结构和运动方式的普遍性与生命动力学

鞘褶皱式的结构样式和运动方式并非韧性剪切带所独有,在自然界和生物界中也广泛存在,是世间万物表现形式和运动的普遍方式,是无机界与有机界、植物与动物连接的纽带与桥梁。鞘褶皱式结构和运动方式的不断变异,是生命发展与演化的主导因素,是生命科学中继DNA双螺旋结构之后的又一新发现。     

Early tides: Response to Varga et al.

Tidal cycling has been causally implicated at the origin of life, but the speed of early tides has not been established. The rotation period of the Earth is the dominant parameter, and a length of day (LOD) of under 6 h at 3.9 Ga was inferred by regression from present values [Lathe, R. 2004. Icarus 168, 18-22]. However, this would imply critical lunar proximity at that time; in their commentary Varga et al. instead argue for a more distant Moon, proposing LOD=16.8 h. The debate is accentuated because regression from current values requires an Earth-Moon juxtaposition at around 2 Ga, for which there is no evidence. A smooth retreat from a Moon-forming impact at 4.5 Ga is also irreconcilable with the weight of paleotidal evidence. An inflection in the lunar recession curve is required to reconcile current and recent Earth-Moon values with a 4.5 Ga origin, requiring a change in tidal friction during the evolution of the Earth-Moon system. Depending on whether this took place at ∼2-2.5 Ga before present, or more recently (∼0.8-0.2 Ga), LOD values are estimated at between 12 and 16 h, suggesting a compromise figure of LOD=∼14 h, with tides every ∼7 h, at 3.9 Ga.     

Biology and Population Dynamics of Donax trunculus L. (Bivalvia: Donacidae) in the South Adriatic Coast (Italy)

Biology and population dynamics of the suspension-feeding wedge clam Donax trunculus (Linnaeus, 1758) were studied for 13 months (November 1994–April 1996) along the Italian Southern Adriatic coast near the Lagoon of Lesina. Specimens were found at depths between 0 and 2 m, mainly in fine grain bottoms. The spatial coastal distribution showed an intraspecific segregation between young and adult wedge clams. A unimodal recruitment (length >4 mm) occurred in winter (December–February). Length frequency distributions were used to determine age and growth rate. Three year classes were regularly observed and their growth pattern defined. The population showed a maximum length of 37 mm and a longevity of 4 years. Analysis of seasonal variations in the reproductive cycle showed that gametogenesis occurred in spring in females. After the spawning season (March–July) females of D. trunculus remained in a resting stage from August to January.     

REVIEWS OF GEOGRAPHIC SOFTWARE

Reviews of geographic software in this article: GEOGRAPHY MACCHORO OPS83 Population Analysis on Microcomputers with PC or MS DOS STATPAC GOLD THUNDERSCAN