Temporal and spatial distribution of dimethylsulfide in the subarctic northeast Pacific Ocean: a high-nutrient–low-chlorophyll region     

C. S. WONG  S. E. WONG  W. A. RICHARDSON  G. E. SMITH  M. D. ARYCHUK  J. S. PAGE 《Tellus. Series B, Chemical and physical meteorology》2005,57(4):317-331

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Temporal variations in the partial pressure and flux of CO₂ at ocean station P in the subarctic northeast Pacific Ocean     

C. S. WONG  Y.-H. CHAN 《Tellus. Series B, Chemical and physical meteorology》1991,43(2):206-223

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Towards a framework for learning with GIS: The case of Urban World, a hypermap learning environment based on GIS     

DEREK THOMPSON  FRANCIS E LINDSAY  PAUL E DAVIS  DAVID W S WONG 《Transactions in GIS》1997,2(2):151-167

Off-the-shelf GIS toolboxes are inadequate for pedagogic purposes. Urban World , an Arc View application, attempts to address this shortcoming by including special features designed to foster student progress towards a better understanding of urban environments. This paper provides context for the Urban World system in an active, authentic learning environment for students of urban geography and planning at junior and senior levels in undergraduate curricula at universities in the United States. The paper describes the rationale for, and implementation of, several components of Urban World : a special graphid user interface; productivity tools for facilitating the acquisition of practical skills of mapping and spatial analysis; tools for accessing, undertaking, and submitting homework assignments in a paper-less class; and various devices for assisting students to undertake spatial reasoning. GIS are Seen as an enabling technology for improving understanding by means of engaging students in empirical analysis. Spatial problem solvers and decision makers reach sound conclusions by employing reasoning skills applied to well-formed databases; scientific research makcs progress with sound reasoning of many types. The effective teaching and learning about the geography of our world requires a strong foundation of spatid reasoning.  相似文献   

近20年来我国村落形态研究的回顾与展望     

车震宇  翁时秀  王海涛 《地域研究与开发》2009,28(4)

近20年来村落形态的定义数量不多,含义不一致,且不够严谨,其研究主要在村落形态类型、影响因素、演变机制、空间结构等方面出现了较多成果。研究方法突破了原有的描述性、定性分析,新的研究方法和手段被引入。村落形态研究不足之处体现在理论研究较少,理论与应用的结合不够;单项研究较多,综合研究较少;宏观研究较多,微观研究缺乏等方面。未来村落形态研究应在以下5个方面拓展:厘清基本概念,建立概念体系;村落形态类型研究应当向纵深发展;应从系统论和整体论的角度研究形态演变机制;建立研究规范,重视研究成果的交流,注重从案例中提炼理论;加强新方法的应用。  相似文献   

Growth and photosynthesis of Chlorella strains from polar,temperate and tropical freshwater environments under temperature stress     

Kok-Keong LEE  Phaik-Eem LIM  Sze-Wan POONG  Chiew-Yen WONG  Siew-Moi PHANG  John BEARDALL 《中国海洋湖沼学报》2018,(4)

Elevated temperatures as a consequence of global warming have significant impacts on the adaptation and survival of microalgae which are important primary producers in many ecosystems. The impact of temperature on the photosynthesis of microalgae is of great interest as the primary production of algal biomass is strongly dependent on the photosynthetic rates in a dynamic environment. Here, we examine the effects of elevated temperature on Chlorella strains originating from different latitudes, namely Antarctic, Arctic, temperate and tropical regions. Chlorophyll fluorescence was used to assess the photosynthetic responses of the microalgae. Rapid light curves(RLCs) and maximum quantum yield( F_v/F_m) were recorded. The results showed that Chlorella originating from different latitudes portrayed different growth trends and photosynthetic performance. The Chlorella genus is eurythermal, with a broad temperature tolerance range, but with strain-specific characteristics. However, there was a large overlap between the tolerance range of the four strains due to their "eurythermal adaptivity". Changes in the photosynthetic parameters indicated temperature stress. The ability of the four strains to reactivate photosynthesis after inhibition of photosynthesis under high temperatures was also studied. The Chlorella strains were shown to recover in terms of photosynthesis and growth(measured as Chl a) when they were returned to their ambient temperatures. Polar strains showed faster recovery in their optimal temperature compared to that under the ambient temperature from which they were isolated.  相似文献   

浙江仙居风景名胜区开发地质公园可行性探讨     

王永  姚辉磊  杜旭 《地质灾害与环境保护》2007,18(4):43-46

仙居风景名胜区位于浙江省仙居县的中南部,本文介绍了仙居风景名胜区地质遗迹资源的基本状况,分析了拟建仙居风景名胜区省级地质公园具备的优势,以及建立地质公园的科研价值、社会经济和文化价值,认为仙居风景名胜区独特的地质遗迹景观符合省级地质公园的标准,建立省级地质公园是可行的,并为申报省级地质公园的工作提出了建议.  相似文献   

The spatial dynamics of foreign investment in the Pearl River Delta, south China   总被引：1，自引：0，他引：1  

JIANFA SHEN  KWAN-YIU WONG  KIM-YEE CHU  ZHlQlANG FENG 《The Geographical journal》2000,166(4):312-322

The Pearl River Delta region in south China has experienced dramatic economic development, industrialization and urbanization since the late 1970s. Foreign investment, especially the capital from Hong Kong, has been one of the major driving forces underlying the process. The spatial concentration/diffusion of foreign investment in a region also has important bearing on the balanced/unbalanced urban and regional development. This issue remains unexamined and critical analysis is needed to unveil the spatial impacts of foreign direct investment (FDI) activities in China. This paper will focus on the Pearl River Delta region to examine the spatial diffusion and the determinants of foreign investment. The diffusion of foreign investment from the provincial capital, Guangzhou and two special economic zones near Hong Kong to surrounding areas is clearly identified. The diffusion is the result of the widespread implementation of open-door policy in the region and significant improvement in infrastructure. Four models of foreign investment are developed to explain the spatial incidence of foreign investment in the region. The findings of this paper can shed light on the regional development process in China and other developing countries under the influence of foreign capital.  相似文献   

改革开放以来广东省空间极化研究   总被引：50，自引：7，他引：43  

甄峰  顾朝林  沈建法  黄钧尧  朱剑如 《地理科学》2000,20(5):403-410

改革开放２０年来广东省的空间结构演化表明：传统的核心－边缘模式已发生了很大的变化,区域出现多极化且次级核心区形成。广州华南中心城市的地位已经被香港所取代,韶关、湛江、汕头、潮阳等老中心城市地位不断下降,深圳、珠海、东莞、中山、顺德、南海和番禺等新兴城市正发展成为新区域增长中心。珠江三角洲经济发展开始向外围地区扩展,出现了反极化的趋势。全省空间差异扩大,形成了多层次的空间极化格局。  相似文献   

遥感技术在土地调查与动态监测中的应用综述   总被引：1，自引：0，他引：1  

翁玉坤  刘排英  王鹏生 《北京测绘》2009,(3):60-62

从土地利用现状调查和动态监测的技术流程入手,以融合成图和土地动态监测为重点,对流程中各个步骤作了明确简要的介绍,并系统地介绍了现代遥感技术在土地调查应用方面的优势和不足。  相似文献   

Characteristics of phytoplankton community structure during and after a bloom of the dinoflagellate Scrippsiella trochoidea by HPLC pigment analysis     

Chun-kwan Wong  Chong-kim Wong 《中国海洋大学学报(英文版)》2009,8(2):141-149

A bloom of the dinoflagellate Scrippsiella trochoidea was detected for the first time in inner Tolo Harbor, Hong Kong in 2 000. Water samples were collected at eight stations along a transect passing through a red tide patch for microscopic analysis of phytoplankton composition and high-performance liquid chromatography (HPLC) analysis of phytoplankton pigments. During the bloom, the density of dinoflagellates was 1.1×10⁶ cells L⁻¹ within the patch and 8.6×10⁵ cells L⁻¹ outside the patch where the phytoplankton community was dominated by diatoms. After the bloom the S. trochoidea began to decrease in density and was replaced by diatoms as the dominating bloom-causing organisms at all stations, and the density of dinoflagellates at most stations was less than 1.0 × 10⁶ cells L⁻¹. The status of S. trochoidea as the causative species of the bloom was indicated by the presence of peridinin, the marker pigment for dinoflagellates. The shift from dinoflagellates to diatoms was marked by the decline of peridinin and the prevalence of fucoxanthin. Phytoplankton pigment markers also revealed the presence of other minor phytoplankton assemblages such as cryptomonads and blue-green algal.  相似文献