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1.
讨论了二维和三维电子地图在空间认知特点、空间认知模式和空间认知效果方面的差异。与纸质地图相比,二维电子的地图的空间认知具有动态性、交互性以及制图和读图过程的模糊化等特点,三维电子地图的认知效率更高、认知维度和深度更广。空间认知模式方面,二维电子地图类似于"阅读式",而三维电子地图则类似于"观看式"。二维电子地图对位置、距离、方向等空间格局的认知效果较好,而三维电子地图对目标、形状等空间对象的认知效果较好。  相似文献   

2.
文章针对中国海洋空间规划涉及的法律、行政法规和地方法规,以及德国海洋空间规划相关领域法律法规进行梳理。在核心法律、立法体系层次、涉及海域、与陆地空间规划的联系4个方面对两国海洋空间规划法律体系进行异同分析,探讨我国未来可行的海洋空间规划法制建设方向。提出推动海洋空间规划专项立法,规范地方立法建设,重视专属经济区与大陆架空间规划,有机结合陆海空间规划等建议。同时展望了我国和世界海洋空间规划法律体系的建设趋势。  相似文献   

3.
提出了一种利用GIS空间分析技术,通过空间插值处理,对目标区域内的各类污染海域进行等级划分,得出各类污染海域面积的方法。通过对污染面积要素进行空间分析:栅格叠加统计分析、栅格转换矢量面、边界平滑处理、微小面积融合处理、要素面无缝处理以及同等级污染面融合处理,生成矢量污染面积图,计算各等级污染面积值,通过海洋专网,利用Arc GIS Server,发布Geopocessing服务。当用户导入插值数据,插值范围,设定条件,就可以获得区域的污染面积,为用户提供远程服务。研发了污染面积计算工具,有助于环保工作者提高工作效率,满足环境质量综合评价中时效性和直观性的要求,具有良好的推广意义。  相似文献   

4.
浙闽沿岸水的空间结构特征及生消过程   总被引:2,自引:0,他引:2       下载免费PDF全文
  相似文献   

5.
基于GIS的城市地下管线空间分析模型的建立与实现   总被引:18,自引:0,他引:18  
为提高城市地下管线的管理水平,利用地理信息系统技术(GIS)的空间分析功能,首先在分析地下管线的的实体-关系模型(E-R模型)的基础上,根据GIS空间分析的特点,提出了基于空间分析的城市地下管线的数据库结构;其次,根据城市管线规划、管理和施工的需要,建立了城市地下管线的纵断面、横断面、最佳路径、地下管线三维分析等几种空间分析模型,并对各种模型的表示内容和实现方法进行了阐述.从而实现了城市地下管线的可视化和动态化管理。该模型在青岛市综合地下管线管理系统应用后,提高了青岛市的城市规划和管线管理水平,促进了各个专业管线管理单位信息化和数字化进程。  相似文献   

6.
山东近海底层鱼类资源空间异质性   总被引:1,自引:0,他引:1  
本文根据2016?2017年山东近海渔业资源底拖网季度调查数据,应用多项空间自相关指标和变异函数,分析了山东近海底层鱼类资源的空间自相关性与空间异质性.结果表明,山东近海底层鱼类资源呈现出显著的空间聚集格局,存在着空间自相关性,其中在春季、夏季和冬季的空间自相关性较强,在秋季的空间自相关性较弱.从空间分布上来看,底层鱼...  相似文献   

7.
长江口盐度的时空变化特征及其指示意义   总被引:19,自引:4,他引:19  
2003年2,7月在长江口进行了枯、洪季大规模综合水文测验,布控范围西自江阴东至口外-20m,测验站点覆盖4条入海汊道.测验资料统计分析表明:(1)径流大小、汊道分流比、潮汐强弱和地形条件是控制盐度时空变化的主要要素;(2)在盐度空间分布上从大至小的顺序是:北支,南槽,北槽,北港口;(3)北支枯季发生盐水倒灌南支,而洪季可有一半以上区段为淡水所控;在其他3个入海汊道中,北港口门段是长江口盐淡水混合相对最弱的区段,盐度潮周期变幅最大,但洪枯变幅最小;南槽的盐淡水混合较强,盐度潮周期变幅较小,但洪枯变幅很大;北槽介于两者之间.(4)盐度时空变化反映洪季北支、南港和南槽分流比都有所增加.  相似文献   

8.
海洋地球物理数据库设计与实现   总被引:1,自引:0,他引:1  
在对海洋地球物理数据类型和特点进行分析的基础上,从海洋地球物理元数据、基础数据库和空间数据仓库等几个方面对海洋地球物理数据库进行设计,并基于C/S和B/S架构开发了海洋地球物理数据库管理系统。经应用实践,该系统能够实现海洋地球物理数据的高效化管理和便捷化共享,提高了数据的使用效率,满足海洋调查、科研、管理等工作的需求。  相似文献   

9.
Fish, epibenthos and macroinfauna were collected in a Zostera marina bed and nearby unvegetated sediments in the estuary of the Damariscotta River, on the mid-coast of Maine. Samples of epibenthic fauna and fish were collected at low tides both during day and night, and samples of infauna at low tides during the day. The mean density of Zostera shoots in the study area was 335 m−2. Abundance and species number of fish were greater at night than during the day and greater in eelgrass beds (Z. marina) than in unvegetated habitats. Daytime fish collections were dominated by Atlantic silversides (Medinia medinia), while juvenile winter flounder (Pseudopleuronectes americanus) dominated night collections. Also Zostera-associated epifaunal abundances and number of species were significantly higher at night than during the day. Mysis stenolepis, Idotea balthica and Littorina obtusata were dominant species in the epifauna samples. Of the total of 37 invertebrate species encountered, only five occurred both in the infaunal and epifaunal samples. Nineteen different taxa were collected from the benthic core samples. The most abundant invertebrate infaunal taxa were sipunculids, the polychaete Nereis virens, and oligochaetes. Infaunal invertebrate abundances and species diversity were significantly higher in eelgrass beds than in unvegetated sediments. The abundance and number of species of benthic invertebrates were also positively correlated to seagrass biomass. Community diversity values (H′) were relatively low but fit well in the general pattern of decreasing diversity towards northern latitudes.  相似文献   

10.
空间数据查询效率的优劣决定着三层体系结构空间信息系统的应用效果。空间数据缓存技术是提高空间数据查询效率的有效方法之一。在数据缓存技术逐渐成熟的今天,如何利用数据缓存技术来构建空间数据缓存是目前研究的热点。基于Microsoft新的数据缓存技术,借助常用的格网索引,在客户端和应用服务器端开辟空间数据缓存区,以降低数据的传输量,减少用户的请求响应时间,从而提高空间数据查询效率。在利用版本控制技术实现空间数据缓存的同时,解决客户端、应用服务器和数据库服务器的数据一致性问题,确保空间数据的有效性和可用性。  相似文献   

11.
Phyllosoma larvae were identified and their distribution was examined, based on the larvae in ichthyoplankton samples collected in the Japanese Eel Expedition to the spawning area of A. japonica in the western North Pacific from August 30 to September 13, 1986 (Leg. 1), and from September 22 to 25, 1986 (Leg. 2), on board the R/V Hakuho-maru. Phyllosoma larvae belonged to 3 families (Scyllaridae, Palinuridae and Synaxidae) representing 6 genera and 14 species. A total of 336 palinurid and synaxid phyllosoma larvae were collected, of which 233 larvae (about 70%) were identical with P. longipes s. l, while a total of 362 scyllarid phyllosoma larvae were collected, of which 274 larvae (about 76%) were identical with S. cultrifer. Phyllosoma larvae of P. longipes s. l and S. cultrifer showed a similar distribution to each other. The larvae were abundant in the water close to Mariana Islands, although late stage examples were abundant in waters of Luzon and eastern Taiwan. Distributions of these larvae may be related intimately with the North Equatorial Current existing along 15°N. The North Equatorial Current approaches the eastern coast of the Philippines and then separates into two branches of northward and southward flows. The northward flow contributes to generating the Kuroshio Current while the southward flow goes to generate the Mindanao Current. Judging from distributions of phyllosoma larvae in the present study, it is assumed that the larvae of the above two species may have been released in Mariana Islands and transported westward from there through the North Equatorial Current. These larvae may then be transported to eastern Taiwanese waters.  相似文献   

12.
基于数字海洋三维地球框架,针对地形通视分析中典型的点对点、点对线、点对面三种情况,分析了通视分析算法及其功能实现,面向不同的业务需求,提供多样化的海洋地理信息量测服务,为用户提供空间决策支持信息,最后对三种通视算法进行了实验分析和效率分析。  相似文献   

13.
This article summarizes briefly the principal conclusions from papers presented in this special issue on marine spatial planning. It identifies potential economic, ecological, and administrative benefits (and costs) that might be realized from the implementation of MSP. Finally, the article summarize lessons learned and identifies future challenges and directions for MSP, including the development of international guidelines for its implementation.  相似文献   

14.
在对地理数据建模过程研究的基础上,论述了地理数据引擎——GDE(geographic data engine)的设计与实现,提出了独立于具体数据结构和文件格式的地理数据访问方法,从概念模型上论述了GDE的相关理论及设计策略,给出了此模型的具体实现。  相似文献   

15.
Ringnet fishing began in the early 20th century and is practised worldwide, mainly to target nearshore pelagic species. The method was introduced to Kenya’s coastal waters by migrant fishers from Tanzania. However, the impacts of this fishing gear remain poorly assessed. We assessed the spatial distribution of ringnet fishing effort and its possible effects on ecosystem components, such as coral reefs, marine megafauna and marine protected areas, on the south coast of Kenya. We tracked 89 ringnet fishing trips made from December 2015 to January 2016 and used spatial multicriteria analysis to determine hotspots of possible environmental risks. The results showed that habitat type and bathymetric profile influenced the spatial distribution of ringnet fishing effort. Mixed seagrass and coral habitats had the highest concentration of the effort. Most of the habitats in the study area were moderately exposed to the impacts of the ringnet fishery. The study identifies high-risk areas that require spatial measures to minimise possible environmental risks of the gear both to habitats and to endangered sea turtles.  相似文献   

16.
空间数据仓库元数据系统的研究与设计   总被引:2,自引:0,他引:2  
介绍了空间数据仓库元数据的概念、功能及元数据系统的组成要素,重点研究了空间数据仓库元数据系统的设计,提出了邦联式与客户机/服务器、浏览器/服务器相结合的系统结构设计方案,并进一步设计了空间数据仓库元数据系统的功能和元数据库信息模型。该系统研究与设计的目的是为了较好地解决空间数据仓库中海量数据的管理、共享及互操作等问题。  相似文献   

17.
The relatively wide KwaZulu-Natal Bight between St Lucia and Durban on the north-east shelf of South Africa is characterised by several circulation features driven by the Agulhas Current, wind and coastal inputs. A large multidisciplinary programme investigated the sources and relative influences of nutrients on the shelf. Within this, and to address a critical knowledge gap, this study describes macrobenthic (<1 mm) composition and frequency from 16 stations, assigned amongst four oceanographic focus areas. The areas were predetermined across the disciplines to represent upwelling, outwelling and a semi-persistent eddy, with nutrients and primary productivity being measured at each. Environmental variables such as sediment distribution, sediment TOC and bottom water physico-chemistry were determined at a significantly larger spatial scale. Our study postulated that oceanographic focus areas support significantly different macrobenthic assemblages, and that composition and relative distribution is due to measurable habitat attributes at each. Macrofauna were relatively abundant and particularly rich at >1 000 taxa. Annelida, Arthropoda, Mollusca, Echinodermata, Sipuncula and Cnidaria (>50 taxa each) were the dominant macrobenthic groups in the bight. Annelida were dominated by the polychaete families Spionidae, Terrebelidae and Cirratullidae, which were generally associated with outwelling and a mud depocentre off the Thukela River. Two unique and distinctive assemblages were found, one in the Thukela Mouth focus area and another on the midshelf between Thukela and Durban. The latter is influenced by poorly sorted, coarse sand and with probable influences from the Durban Eddy. There assemblages were abundant, rich and specific to this habitat. Correlation, PERMANOVA and CAP analyses showed assemblage fidelity to the focus areas. Medium sand, fine sand, mud and the variance of overall sediment type were the habitat drivers underlying macrofaunal abundance distributions.  相似文献   

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广东省风暴潮时空分布特征及重点城市风暴潮风险研究   总被引:1,自引:0,他引:1  
收集、整理、分析1949年以来广东省10个典型验潮站的近500站次台风风暴潮过程,开展了广东省台风风暴潮和超警戒风暴潮时空分布特征研究。结果表明:广东省台风风暴潮主要发生时间为7—9月,其中7月最多、9月次之,雷州半岛东岸无论发生次数还是强度都明显偏多、偏强,其次为阳江;风暴潮灾害则主要发生在7—10月,以7月最多;风暴潮灾害频发区依次为珠江口、雷州半岛东岸、阳江和汕头,风暴潮灾害严重区依次为汕头、阳江和雷州半岛东岸,阳江和雷州半岛东岸为风暴潮灾害频发区和严重区。选取受台风风暴潮影响频繁和严重的典型区域阳江市。利用业务化的台风风暴潮模式开展了不同等级台风影响下阳江市的最大风暴潮风险研究,中心最低气压为970hPa的台风在最有利路径下产生的风暴潮为185cm,约20a一遇,940hPa的台风产生的风暴潮为310cm,约为500a一遇。  相似文献   

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