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11.
钱进 《地理空间信息》2019,17(7):39-44,I0001
基于国产高分辨率卫星影像和基础性地理国情监测数据,利用GIS技术分析了2013~2017年大渡口滨江老工业区搬迁改造实施的效果。结果表明,绿地面积呈增加趋势,增加量为1.28km^2,主要为天然草地;城市建设用地不断增加,用地性质日趋合理,其中工业用地、物流仓储用地和公共服务设施用地不断减少。空气质量总体较好,呈明显的季节性变化趋势。2017年空气质量优良天数为283d,说明搬迁改造工作成效显著。  相似文献   
12.
From 2000 to 2006, a total of 75 bivalve species were identified, varying from 29 (spring 2001) to 54 species (spring 2005) per year. Seasonal tendencies in diversity varied according the year, thus the interpretation of long-term and regional scales is essential before drawing any conclusions in other studies. Richness and diversity consistently decreased with depth and increased with sediment grain size (from low in very coarse sand to high in coarse silt). Diversity decreased progressively from 3 to 16 m depth, thus the harsher shallower environments (due to waves and tidal air exposure) showed greater diversity than the most stable areas. Communities in finer sediments were more diverse than those in coarser sand. Evenness showed patterns opposite to diversity, overall.Diversity and evenness maps (produced with multivariate universal kriging), showed that most geographic areas with greater diversity were farer from river outflows and wastewater treatment plants. Two types of geographic pattern were observed: areas with persistently greater bivalve diversity through time and areas that changed locally from year to year. This spatial analysis can be used to establish priority conservation areas for management purposes, and to analyse the persistency of regional diversity patterns. The area with most habitat heterogeneity (Sotavento) corresponded to greatest diversity.There was a positive relationship between Spisula solida and Chamelea gallina landings and bivalve diversity 2 years and 1 year later, respectively. Possibly, local fisheries, by selectively withdrawing the commercial numerically dominant species from the ecosystem, increased diversity 1 to 2 years later, as the ecological niches of the dominants are quickly filled by several other species thereby creating a more even community. On regional scales, no significant impact was found on long-term bivalve diversity in local fisheries,  相似文献   
13.
基于地理信息系统的太阳直接辐射与冰川物质平衡的关系   总被引:3,自引:1,他引:3  
丁永建 《冰川冻土》1998,20(2):157-162
基于冰川微地形对冰川物质平衡重要影响的认识,在考虑朝向、坡度、地形遮蔽等因素的条件下,以地理信息系统为手段,对乌鲁木齐河源1号冰川冰面太阳可能直接辐射进行了理论计算.在此基础上,建立了计算冰面任意一点物质平衡的B=f(T,R)(气温-辐射)模型.比较了该模型与B=f(T)(气温)模型、B=f(P,T)(降水-气温)模型及B=f(Q)(能量平衡)模型之间的优缺点,表明该模型具有物理意义明确、计算精度较高、参数易于获得等优点,从而为计算冰川物质平衡提供了新的途径.  相似文献   
14.
Despite the constant expansion of the application of GIS, in recent years, the data process-ing ability of the application system developed with GIS_Tool is quite limited. Management information system with the geographical information can not only be used to deal with data commonly, but also deal with digitized maps as GIS_Tool does. Thus it can help the user develop an application system high-qual-ified both in maps and traditional data. This paper, by taking the method of integrated MapInfo in the application of Visual Basic as an example, mainly illustrates two technological problenm-integrated map technology and the multiuserization of Maplnfo geographical information. And also the concrete solu-tions to the problems are provided.  相似文献   
15.
以云南省会泽县为例,基于ETM+、ASTER、DEM等遥感影像数据运用ArcGIS、ERDAS等遥感软件提取研究区的植被、地形、坡度坡向等一系列地理特征信息,并生成相关图件,为本区的农业规划、水土流失、地质灾害、资源开发、土壤侵蚀等相关研究提供多方面的空间信息参考.  相似文献   
16.
以MAPGIS软件为基础平台 ,利用GIS缓冲区分析和空间叠加分析技术 ,研究上海及邻近海域地震与活动断裂的关系。研究区地震活动断裂的发育程度以继承性NE -NNE向为主 ,但其活动强度不及NW -NNW向及近EW向断裂 ;沿NW -NNW向及近EW向断裂两侧 ,中强地震发生频率明显高于NE -NNE向断裂 ;不同时代活动断裂与中强地震之间存在一定的联系 ,表现为随着断裂活动时代变新 ,断裂周围中强地震发生的频率升高。  相似文献   
17.
The Gran Campo Nevado (GCN) forms an isolated ice cap on the Península Muñoz Gamero (PMG) located 200 km to the south of the Southern Patagonia Icefield (SPI). We present a glacier inventory of the GCN made up by 27 drainage basins (in total 199.5 km2) and other small cirque and valley glaciers of the southern part of PMG (in total 53 km2). The glacier inventory is based on a digital elevation model (DEM) and ortho-photos. Contour lines from maps, relief information derived from Landsat TM satellite imagery from 1986 and 2002 and stereoscopic data from aerial photos were combined in a knowledge-based scheme to obtain a DEM of the area. A digital ortho-photo map based on aerial photos from 1998 and several ortho-photos based on aerial photos from 1942 and 1984 could be produced from the initial DEM. A geographical information system (GIS) served to outline the extent of the present glaciation. All major glaciers of the GCN show a significant glacier retreat during the last 60 yr. Some of the outlet glaciers lost more than 20% of their total area during this period. Overall glacier retreat amounts to 2.8% of glacier length per decade and the glacier area loss is 2.4% per decade in the period from 1942 to 2002. We hypothesise that GCN glaciers may have reacted faster and more synchronously with the observed warming trend during recent decades when compared with the SPI.  相似文献   
18.
Book Reviews     
Committee on Protection and Management of Pacific Northwest Anadromous Salmonids Upstream: Salmon and Society in the Pacific Northwest Cook, Ian G; Doel, Marcus A. and Li, Rex (eds.) Fragmented Asia: Regional Integration and National Disintegration in Pacific Asia Crush, Jonathan Power of Development de Blij, H. J., and Muller, Peter O. Physical Geography of the Global Environment Hayward, David J. International Trade and Regional Economies: The Impacts of European Integration on the United States Kennedy, Michael The Global Positioning System and GIS: An Introduction Lowe, Philip; Marsden, Terry and Whatmore, Sarah (eds) Regulating Agriculture Marsden, Terry; Lowe, Philip and Whatmore, Sarah (eds) Labour and Locality: Uneven Development and the Rural Labour Process Marsden, Terry; Lowe, Philip and Whatmore, Sarah (eds) Rural Restructuring: Global Processes and Their Responses Whatmore, Sarah; Marsden, Terry and Lowe, Philip (eds) Gender and Rurality Whatmore, Sarah; Marsden, Terry and Lowe, Philip (eds) Rural Enterprise: Shifting Perspectives on Small-Scale Production Martopo, Sugeng and Mitchell, Bruce (eds) Bali: Balancing Environment, Economy and Culture Ould-Mey, Mohameden Global Restructuring and Peripheral States: The Carrot and the Stick in Mauritania Redclift, Michael and Benton, Ted (eds) Social Theory and the Global Environment Thomas–Slayter, Barbara and Rocheleau, Dianne Gender, Environment, and Development in Kenya: A Grassroots Perspective Wallach, Bret Losing Asia: Modernization and the Culture of Development Wennberg, John E. Dartmouth Atlas of Health Care Wilson, David and Huff, James O. (eds) Marginalized Places and Populations: A Structurationist Agenda  相似文献   
19.
巢湖凌家滩遗址古人类活动的地理环境特征   总被引:3,自引:0,他引:3  
通过对巢湖凌家滩文化遗址的野外勘查、采样和室内磁化率、烧失量、化学元素及光释光年代分析,结合巢湖湖泊岩芯记录的中全新世环境特征、研究区较高分辨率遥感影像和文物考古成果,综合研究表明:古凌家滩人生活于中全新世气候适宜期,其文化的发展和繁荣处在气候由温暖湿润向温和略干转换的过渡阶段;晚更新世末期堆积形成的地面(OSL年代11.6 ±1.0 ka B.P.)是古凌家滩人生活的地貌面,本区古地貌面海拔以及拔河高度与现今不同,这与该区新构造运动沉降和气候-水文因素作用有关;中全新世温暖湿润的气候条件下,太湖山南麓台地被进一步切割为山前长条形岗地与河流相间的地貌形态,遗址所在的长岗岗地是东、西、南三面临水的"半岛"环境,河川相连,便于水运交通、渔猎和水稻种植。  相似文献   
20.
中国流动人口的城市宜居性感知及其对定居意愿的影响   总被引:2,自引:2,他引:2  
流动人口是中国城镇化进程的重要参与者,加强其定居意愿特征分析对制定中国新型城镇化发展政策具有重要参考价值。基于中国40个主要城市的宜居城市问卷调查数据,运用描述统计和地理探测器方法,揭示中国流动人口的城市宜居性感知特征及其对定居意愿的影响。研究结果表明:①中国流动人口的城市宜居性感知评价分异明显,呈现出“公共服务设施便利性>自然环境舒适性>社会人文环境舒适性>环境健康性>交通便捷性>城市安全性”的递减特征;②中国流动人口的公共服务设施便利性、社会人文环境舒适性、环境健康性和城市安全性等4个维度城市宜居性感知对其定居意愿具有显著影响,且影响强度依次递减,但二者关系并不完全呈简单的线性特征。③相对他人收入满意度、生活满意度、住房价格感知和地理区位等参照变量,以及年龄、性别和职业等个体与家庭属性也是影响中国流动人口定居意愿的重要因素。  相似文献   
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