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1.
“West Jilin Porovince” in ths paper means Zhenlai,Baicheng,Taonan,Da‘an,Tongyu,Fuyu,Songyuan,Qian‘an ,Chandling,also includes Gongzhuling,Shuangliao,Lishu,Siping and Nong′an which have been suf-fered from desertification.In west Jilin Province there are three sand zones passing through,they are Xiang(Xianghai)-Wu(Wlan Tug)sand zone,Hai-Fent sand zone,and Tao′er River right band sand zone.The desertification area of west Jilin Province is 819 100ha,making up 12.5% of the total land area.Among desertification types,in Jilin Province light desertification is the major,then is medium dersertification,hevey desertification is the least.According to the compare-son of the interpretation results of the Landsat images of the 1980s and 1990s by remote sensing and GIS techniques,it can be seen that the diesertification area in west Jilin Province basically didn′t change on the whole,only increased 6130ha,making up 0.8% of the desertification area,change scale is less than 1%.Evidently,desertification is con-trolled mostly,but some areas are continuing deterioration.The desertification process of China can be divided into three types according to origin nature,they are sandy steppe desertification,fixed sand area(sand land) activation and dunes transfer invasion.Reasons of desertification of West Jilin Province are analyzed,they include natural factors(such as material source factors,chimate factors) and artificial factors(such as destroying grass to reclaim,steppe decreasing greatly,illegally feeling shelter forest stands,constructing reservoir to influence eco-environment etc.).Some sugges-tions are put forward as follows:establishing the social project for ecological reconstruction of degenerated land;intensify-ing planning and management of land use,reverting farmland into forestland or pasture in a planned way.The key desertifica-tion control is to depend mainly on policy and management,then control techniques.  相似文献   

2.
本文系统阐述了《军官地图集》电子版的设计和研制中的若干问题,包括《军官地图集》电子版的总体设计、数据库设计、自动分幅设计以及专题图设计等。总体设计主要包括系统的结构设计、地理数据库设计、各功能模块设计等几部分。在地图集系统中,多比例尺海量地理数据的应用必然要求有强大的数据库支持,系统中采用了易于存储、便于管理的数据结构,并对数据库的各类数据描述表进行了详细说明。自动分幅设计是电子地图集的一个新功能,本文提出了电子地图集的分幅方式:经纬线分幅、矩形分幅、名称分幅和区域分幅,并阐述了它们各自的优缺点。《军官地图集》电子版中的专题地图在设计上突出了图集的系统性和军事特色,本文提出了该电子版中专题地图设计的原则和方法。根据该电子版的设计和制作过程,同时提出了电子地图集制作的步骤,并阐明了电子地图集设计中的不足和发展方向。  相似文献   

3.
香港揽胜太空影像地图集是一本区域性综合地图集。作为信息时代的区域综合地图集的设计和编制,我们认为应该把重点放在对资源信息的深加工上,应用遥感技术、地理信息系统、计算机制图、电子制版与四色印刷技术,才能为政府决策部门提供区域可持续发展更加实用的信息产品。  相似文献   

4.
针对生态环境类电子地图集这种新型的专题性电子地图集在信息构成和功能上的特殊性,首先,研究和确定了它的主题定位和功能定位,提出集信息可视化和空间分析、虚拟仿真等功能于一体的理念。其次,提出并构建了生态环境类电子地图集的新颖的数据模型,第三,研究并阐述了该类电子地图集的专题图型和表达方法,第四,设计并实现了这种电子地图集的体系结构和技术系统,通过丰富的电子地图实例阐述本文的技术和方法创新点。  相似文献   

5.
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980-2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995-2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development.  相似文献   

6.
设计和编制海陆统筹的综合航海地图集服务于国家“构建海洋命运共同体”发展目标,同时也是促进海陆文化共融和海陆睦邻合作的重要推力,在当前地图学领域受到普遍关注。本文通过与航海专题图、陆地专题图的对比分析,从地图选题、比例尺、投影、地理分幅等方面探讨了海陆统筹地图集的表达特点,并从海陆并蓄视角出发,提出综合航海地图集基础地理框架的内容体系和构建策略。在此基础上,结合《世界航海地图集》的编制实践设计了其基础地理框架的具体建立方案:① 中小比例尺地图使用WGS84坐标系,较大比例尺地图使用CGCS2000坐标系;② 根据专题内容、制图区域、变形需要,制图单元可以使用等差分纬线多圆锥、墨卡托、古德等多种投影;③ 地理底图分为世界地图、典型区域地图、陆地地图、海域地图、航区地图、港口地图6种图型,其系列比例尺内容需按一定规则进行取舍和化简派生得到;④ 地图制图单元采用北方定向,联合地理分幅和地图分幅可生成灵活的图面布局。世界航海专题图集的编制实践表明,应用本文建立的基础地理框架能较好实现海洋与陆地的协调统一表达。  相似文献   

7.
Land use/land cover change (LUCC) is a focus of the research of global environmental changes.The middle and upper reaches of the Yangtze River,which are the most ecologically fragile mountainous area in China as well as one of the areas in China with most notable LUCC, have been on the Chinese Government‘s list of priority areas for ecological restoration. This paper is to reveal the trend of LUCC and the ecological degradation arising from it, and to provide a basis for the future sustainable use of land resources in the region based on a detailed analysis of Yiliang County. Based on the county‘s land use/cover maps in 1960, 1980 and 2000 drawn with the aid of aerial photograph interpretation, field investigation and GIS based spatial-temporal data analysis, LUCC during 1960-2000 period and the ecological degradation arising from it were analyzed. Using the Markv model, the paper brings out a forecast of what the county‘s LUCC would be like if the county‘s current land use continues, as well as the reasons and countermeasures for restoring degraded ecosystems.  相似文献   

8.
提出了将园林景观设计图与地图融合的思路来构建园林景观地图。论文重点讨论园林景观设计与地图在表达内容、要素表达方法、空间理念等之间的互通之处,基于它们的关联分析,以香港斧山公园为例说明园林景观地图的实现方法。园林景观地图结合了园林景观设计与地图的优点,既有园林景观设计的写意与美观,又有地图的可量测性和现势性,有效地实现了地图抽象性与景观设计形象性的结合。  相似文献   

9.
On the basis of the soil environment investigation in Da'an City, Jilin Province, China, 40 soil samples from main land use types were obtained and tested by standard method. Soil organic matter (SOM), total N (TN), total P (TP), total K (TK), available N (AN), available P (AP) and available K (AK) were chosen as the evaluation factors. A regional soil nutrient evaluation model was developed based on the matter-element model. The results show that the soil samples with nutrient grade Ⅱ-Ⅴ respectively account for 10%, 30%, 32.5% and 27.5%, and those with grade Ⅳ and Ⅴ account for 60% in all samples. The relationship between soil nutrients and land types indicates that the nutrients of farmland are relatively good, with 41.7% of soil samples with the nutrient grade Ⅳ and Ⅴ. The nutrients of saline-alkali land and sandy land are the worst, with 100% of soil samples with the nutrient grade Ⅳ and Ⅴ. And the ratios of soil samples grade Ⅳ and Ⅴ in grassland and wasteland are respectively 62.5 % and 54.55%. Generally speaking, the soil nutrients status in Da'an City is poor, 60% of soil samples are in poor and extremely poor conditions, indicating that the soil has been severely eroded. Being a relatively superior evaluation method with more accurate resuits and spatial distribution consistency, matter-element analysis is more suitable for regional soil nutrient evaluation than previous models.  相似文献   

10.
我国电子地图研制的实践及其发展方向   总被引:9,自引:0,他引:9  
本文对我国电子地图的研制作了概述,并提出了今后发展方向。全文共分3个部分:(1)我国创作的已出版和制作的电子地图和电子地图集可区分阅读型、交互型和网络型3种;(2)介绍了面向对象的电子地图模型,建立电子地图图层创作模版和电子地图软件系统(EA-World)的开发,以及总结了电子地图设计的一些问题;(3)分析了电子地图今后研究方向.提出开展现代地图学理论研究,指导电子地图的创作,开展网络地图学研究,实现地图信息共享:以及进一步进行电子地图的数据模型和设计研究,提高电子地图创作质量。  相似文献   

11.
地图集的地图可视化设计与单幅地图不同,需要以地图集的总体设计思想为依据,在地图设计与表达时反映指标体系的科学完整性,体现地图集的总体协调性。本文以《中华人民共和国人口与环境变迁地图集》为例,详细介绍了以多指标、长时间序列为特征的人口与环境变迁地图的可视化设计与表达方法,包括:系列地图、结构及其数量变化、构成比例变化、数量变化及其对比关系、累积数量变化、多指标数量累积及其对比、相对某一时间基点变化、单指标多年统计特征的变化、单指标两个时期数据的对比等。该方法以对相关指标现状的表达为基础,重点强调制图对象变迁特征,表达指标体系之间的联系和区别。相关地图可视化设计方法可广泛应用于其他类似专题地图的设计过程中。  相似文献   

12.
本文探究中国古-近-现代地图的传承和发展脉络,有地图制图技术传承和地图数据资料传承两重含义。中国古代地图学对近代地图学影响最大的是“计里画方”技术、西晋裴秀的“制图六体”理论、唐代贾耽的制图方法和作品、宋代沈括的二十四位向和“制图七法”、元代朱思本理论和技术体系及其地图作品5项成果。明代地图制图的传承和发展有3个分支(传承线),即传统疆域和全国地图制图、航海图和海防图、引入西方制图技术后的近代地图萌芽;清代地图学的传承和发展的5个分支(传承线),即皇家主导的全国地图制图、民间自发的全国地图制图、世界地图制图、海洋图制图、工程地图制图;民国时期的地图制图传承和发展的6个分支(传承线),即私营出版社制图、专题地图制图、航海和航道地图制图、工程地图制图、地形图制图、军事地图制图。中国古代和近代地图,对当今的地图学而言,有丰富的史料、文物价值,也有一定的信息承载价值,但在利用上有相当的难度,需要我们深入研究,探讨出适合的地图再利用模式;从地图表现形式来看,现代地图学似乎有“仿古”的趋势,但这是科学发展的一种螺旋式上升,代表了从古代地图到现代地图传承与发展的“否定之否定”的辩证式升华。  相似文献   

13.
现代地图与地图学概念认知及学科体系探讨   总被引:2,自引:0,他引:2  
现代地图与地图学是传统地图与地图学发展到现代阶段的必然结果。本文重点探讨现代地图与地图学的基本概念和学科体系。文章从现代地图的特性、功能、构成要素/基础及拓展,以及地图科学分类及拓展等基本问题入手,分析了国内外现代地图与地图学概念定义的发展演变,给出了现代地图与地图学较为精练、准确的概念定义;讨论了现代地图学的学科结构体系和由传统到现代过渡时期的学科基本名称与研究内容;最后展望了未来地图学的发展前景。  相似文献   

14.
自明代杰出的地图学家罗洪先(1504-1564年)所编制的《广舆图》(1541年)和利玛窦带来西方精确地图测绘技术开始,中国的地图制图技术已经迈入了近代地图学的门槛,因此,明-清-民国是中国近代地图学从雏形走向成熟的完整阶段[1]。随着现代地图的应用与发展广泛、深入,抽象的概括型地图符号及普通的二维平面地图已不能满足读图者的需求,制图者开始探索虚拟现实、三维地图等表达方法,这与中国近代传统制图的写景法有异曲同工之处。所以,对中国近代地图制图技术及表现方法的研究,对于现代地图学的发展具有重要作用。本文通过阅读大量的中国近代(即明、清、民国时期)的地图资料,查阅前人的研究资料,总结和提炼了中国明、清、民国3个不同时期地图制图的技术,分别阐述了3个时期地图要素、表示方法及其制图技术的发展。  相似文献   

15.
信息时代的地图集编制无论在理论上还是在实践上都有着巨大的创新空间。区域地图集旨在反映区域的主要特征,为区域研究和决策提供依据。在区域性综合地图集的设计中,我们把区域可持续发展的观念作为切入点,运用综合制图的概念对区域相关数据进行信息重组和数据挖掘,从而体现现代地图功能飘移的思路。同时应用数字地图集编制系统,为地图集数据的更新,多方利用创造条件。  相似文献   

16.
导航电子地图多尺度显示与载负量的研究   总被引:1,自引:0,他引:1  
导航电子地图的多尺度显示目的就是在导航终端有限的屏幕容量下,形成适宜载负量的地图.本文在对导航电子地图载负量指标进行研究的同时,将导航电子地图用于显示的道路形状数据、背景数据、地名数据,按照每一类要素的几何大小或重要程度再分为若干级别,利用分级显示技术,计算出导航电子地图各级显示尺度下的合理载负量,使导航电子地图在多尺...  相似文献   

17.
中国近代史上开眼看世界第一书《四洲志》的主编林则徐,亲自命名并委托魏源担任主编完成的《海国图志》,于1842-1852年连续3次出版,迅速传到日本并被争相购买,而在中国却被皇宫束之高阁。直至1978年中国实施改革开放,史地学界开始了研究《海国图志》的热潮,并高度评价其为“最完备的介绍世界历史地理的鸿篇巨著”、“中国近代第一本自编世界地图集”等。为了探索《海国图志》的成功秘诀,本文首先分析了《海国图志》100卷版内容构成,概括了《海国图志》发表后在中国与日本的不同反响;接着,重点探讨了《海图图志》的“设计思想、内容编排、编纂技术”等方面的地图学价值,以及”师夷长技以制夷”的编辑策略,着重于资料真伪分辨和发挥综合体裁协同效果等成功经验;最后,呼吁当今地图工作者努力吸取《海国图志》的宝贵经验,尽快编纂出版一本“内容真实、大型综合、服务民众”的综合性世界地图集。  相似文献   

18.
Improving comprehensive agricultural productivity is an important measure to realize agricultural modernization.Based on the data from Jilin Statistical Yearbook,this study analyzed the spatial and temporal characteristics of comprehensive agricultural productivity discrepancy in the main agricultural production areas of Jilin Province,China.The comprehensive agricultural productivity of 25 county-level administrative units were evaluated by a comprehensive index system based on five aspects which included 20 indicators from 2004 to 2017.The pattern of the discrepancy was analyzed by the spatial differentiation indices and spatial convergence theory.The results were as follows:1) the overall comprehensive agricultural productivity was in a 'W-type' rising trend;2) the discrepancy was in'inverted W-type' trend;3) the spatial distribution characteristics were mainly discrete plaque and 'inverted V-type';4) the formation of differences was forced by a combination of internal and external driving forces.Our study demonstrates the effectiveness of rising agricultural productivity and the level of economic and social developments in different counties in Jilin Province.  相似文献   

19.
EFFECT OF ELECTRIC FERTILIZER ON SOIL PROPERTIES   总被引:2,自引:0,他引:2  
Electric fertilizer, i. e. exerting electric field on plants during growing season instead of chemical fertilizer, is a kind of physical fertilizer, and the third kind of fertilizer with developmental prospect after inorganic fertilizer and organic fertilizer. For the purpose of studying the changes of physical and chemical properties of soil after exerting electric field, five treatments with different applications of chemical fertilizer were arranged on the black soil in Yushu City of Jilin Province by randomized block method, and electric field was exerted on plants every ten days during the growing season. Through sample analysis the paper arrives at following conclusions: 1) Exerting electric field can make soil‘s granular structure increase, bulk density decrease, moisture capacity increase,thus improving the perviousness of soil. 2) Exerting electric field can make microorganism‘s number increase and activity strengthen, thus activating nutrient and increasing organic matter content. 3) Exerting electric field with 0.1A medium has the best effect. So the chemical fertilizer can be saved. Therefore, we can say that the application of electric fertilizer is favorable for decreasing chemical poison, improving soil, relaxing the contradiction between the supply and demand of chemical fertilizer, and decreasing production cost of agriculture and forestry.  相似文献   

20.
数字制图中地图符号的标准化研究   总被引:15,自引:0,他引:15  
随着地理信息技术和数字技术的发展,电子地图的制作日益简便,应用日益普及,数字化网络化传播日益广泛,故此,电子地图符号的规范化、标准化势在必行,以保证地理信息感知和认知的一致性和准确性。在传统纸张地图图式规范的基础上,本项研究参照国际类似的标准文本,电子地图符号体系和符号实体应当适应数字技术和视觉环境的变化,进行合理的改进,原则上继承纸张地图符号的内容分类体系和形状分类体系,延续长期以来形成的纸张地图阅读的地理信息传输与读者认同的惯性。在深入审视符号视觉变量及符号视屏显示的复杂特征之后,提出对基本符号实体内容适当简化、对符号色彩、图元组合关系适当调整的实验方案,在通用地理信息系统软件平台上制作了基本地理底图的符号库标准草案,通过相关地图项目进行了大量的效果对比试验,并多次征求同行意见进行了补充、修改和完善,并在“中国空间信息网”网站上发布。  相似文献   

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