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431.
采用无人机分层测绘技术,对城市河道及其周边水环境现状进行测绘,通过识别存在的问题确定需要治理的具体区域。实践表明,通过分层和类别划分,该技术能够突出测绘的重点以及精准识别水污染情况,应用UAS master软件综合处理单次测绘数据能够获取最终成果,在城市河道水环境治理和管理中无人机分层测绘技术具良好的实用性和可行性。 相似文献
432.
我国地处欧亚板块东缘,地貌类型多样,地质条件复杂,国家重大战略的顺利实施与生态文明建设的有效推进面临着严峻的地质安全风险,因此亟需解决各种地质作用对人居环境与工程活动带来的地质安全问题。本文以地球系统科学为指导,以圈层相互作用、内外动力耦合、人地协调互馈为理论核心,聚焦国土空间地质安全、重大工程地质安全、城市建设地质安全、生态环境地质安全及资源开发地质安全等方面,分析国家战略发展面临的重大地质安全挑战,剖析地质安全牵引出的系列前沿科学问题,勾画出地质安全主要研究方向。地质安全是保障人民高质量生活、推动社会经济绿色发展、构建宜居地球的重要前提,对于解决当前和今后发展面临的重大工程建设、重大灾害防控、生态环境保护和人地和谐安居等相关地质安全问题,推进科技进步与社会可持续发展具有重要科学意义。 相似文献
433.
根据全国土地管理的形式要求,国家土地局在全国范围选定了几个大中型城市开展了土地登记代理制的试点工作。这项制度是根据我国目前的实际情况,借鉴国外成功经验而 相似文献
434.
促进城市建设用地的节约集约利用已经成为当前土地管理工作的共识,然而如何衡量土地节约集约利用却是一个困难而重要的问题。本文以湖南省的14个市(州)城区作为评价对象,首先结合地区特点建立指标体系,然后运用层次分析法,求出各因素因子的权重,在此基础上计算各城区建设用地集约度综合得分并进行排序,最后分析各城区建设用地集约度比较评价结果。 相似文献
435.
《国土资源导刊(湖南)》2007,4(6):27
党的十六大以来的5年是常德市经济又好又快发展的5年.在市委、市政府的正确领导下,狠抓了"民生"、水利、能源、交通、教育、工业等方面的建设,使常德的经济社会发展迈上了一个新台阶.国民生产总值跻身于全省三甲.全市共完成576个项目,用地10118.1公顷(151771亩).为城市经济发展发挥了积极作用. 相似文献
436.
遥感技术在第二次土地调查中的应用 总被引:1,自引:0,他引:1
杜施 《国土资源导刊(湖南)》2007,4(5):34-37
土地遥感是利用遥感技术进行土地调查和土地管理的技术方法。我国从1996年起开展了全国50万人口以上城市的土地利用遥感动态监测。在1984年开展的国土资源大调查(第一次全国土地调查)中,土地资源遥感动态监测被列为重点项目之一, 相似文献
437.
作为推动海岛城市发展的“山海协作”工程,在扩大范围的同时应向纵深度迈进,从追求项目数量向追求项目质量转变,从劳动密集型项目向知识密集型项目转变,从引进项目向引进人才转变。 相似文献
438.
Improvement of Urban Impervious Surface Estimation in Shanghai Using Landsat7 ETM+ Data 总被引:2,自引:2,他引:0
Wenze Yue 《中国地理科学(英文版)》2009,19(3):283-290
This paper explores the potential to improve the impervious surface estimation accuracy using a multi-stage approach on the
basis of vegetation-impervious surface-soil (V-I-S) model. In the first stage of Spectral Mixture Analysis (SMA) process,
pixel purity index, a quantitative index for defining endmember quality, and a 3-dimensional endmember selection method were
applied to refining endmembers. In the second stage, instead of obtaining impervious surface fraction by adding high and low
albedo fractions directly, a linear regression model was built between impervious surface and high/low albedo using a random
sampling method. The urban impervious surface distribution in the urban central area of Shanghai was predicted by the linear
regression model. Estimation accuracy of spectral mixture analysis and impervious surface fraction were assessed using root
mean square (RMS) and color aerial photography respectively. In comparison with three different research methods, this improved
estimation method has a higher overall accuracy than traditional Linear Spectral Mixture Analysis (LSMA) method and the normalized
SMA model both in root mean square error (RMSE) and standard error (SE). However, the model has a tendency to overestimate
the impervious surface distribution.
Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40701177) 相似文献
439.
Urban three-dimensional expansion and its driving forces —A case study of Shanghai, China 总被引:4,自引:1,他引:3
Longyu Shi Guofan Shao Shenghui Cui Xuanqi Li Tao Lin Kai Yin Jingzhu Zhao 《中国地理科学(英文版)》2009,19(4):291-298
Urban expansion is a phenomenon of urban space increase, and an important measuring index of the process of urbanization.
Taking Shanghai as an example, the changes of urban average height and built-up area were studied to represent city’s vertical
and horizontal increases respectively, and statistical methods were used to analyze the driving forces of urban expansion.
The research drew following conclusions: 1) The urban expansion process of Shanghai from 1985 to 2006 had a clear periodic
feature, and could be divided into three stages: vertical expansion in dominance, coordinated vertical and horizontal expansion,
and horizontal expansion in dominance. 2) The average height and quantity of buildings in core city were significantly bigger
than those in suburbs, but the changing speed of the latter was faster. And 3) urbanization process was the major driving
force for the city’s horizontal expansion, while industrial structure improvement was the key driving factor for the vertical
expansion. Those two driving forces were simultaneously affected by city’s political factors. 相似文献
440.
Material dematerialization is a basic approach to reduce the pressure on the resources and environment and to realize the sustainable development. The material flow analysis and decomposition method are used to calculate the direct material input (DMI) of 14 typical mining cities in Northeast China in 1995-2004 and to analyze the demateri-alization and its driving factors in the different types of mining cities oriented by coal, petroleum, metallurgy and multi-resources. The results are as follows: 1) from 1995 to 2006, the increase rates of the DMI and the material input intensity of mining cities declined following the order of multi-resources, metallurgy, coal, and petroleum cities, and the material utilizing efficiency did following the order of petroleum, coal, metallurgy, and multi-resources cities; 2) during the research period, all the kinds of mining cities were in the situation of weak sustainable development in most years; 3) the pressure on resources and environment in the multi-resources cities was the most serious; 4) the petro-leum cities showed the strong trend of sustainable development; and 5) in recent years, the driving function of eco-nomic development for material consuming has continuously strengthened and the controlling function of material utilizing efficiency for it has weakened. The key approaches to promote the development of circular economy of min-ing cities in Northeast China are put forward in the following aspects: 1) to strengthen the research and development of the technique of resources' cycling utilization, 2) to improve the utilizing efficiency of resources, and 3) to carry out the auditing system of resources utilization. 相似文献