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81.
香港的土地利用与环境保护 总被引:1,自引:0,他引:1
香港地区地域狭小,地形崎岖,可利用地少,人口众多,用地紧张,但严谨的用地政策、规划用地和严格管地,使城镇有序,城乡结合协调,基础设施完善,做到合理用地,有效用地和高效用地,从而成为一座名副其实、整洁、美丽的现代化国际大都市。 相似文献
82.
83.
南宁、百色盆地红土风化壳的地球化学特征及其环境意义* 总被引:4,自引:0,他引:4
本文以广西南宁盆地那桐风化壳,及百色盆地江泽风地壳的大量土体化学分析数据为依据,进行了第四纪红土的确认、形成、分布和土壤肥力状况。以及通过地球化学强度、硅铁系数、硅铝系数等指标进行了两风化壳的对比研究。同时,还探讨了风化壳的发育过程及其与环境的关系。 相似文献
84.
祁连山地区1310年以来湿润指数及其年际变幅的变化与突变分析 总被引:23,自引:0,他引:23
本文通过用树木年轮资料重建的祁连山地区5~7月份1310年以来的湿润指数序列,建立了一个反映该地区湿润指数年际变幅序列,对这两个序列分别进行了等级分类和干湿、强弱的时段分析,并用最大熵谱分析法对这两个序列的不同时段分别进行了周期分析。采用HK突变检验方法对这两个序列分别进行了突变分析,发现祁连山地区的湿润指数及其年际变幅存在明显的突变年份。 相似文献
85.
秦岭造山带新生代构造隆升与区域环境效应研究 总被引:16,自引:0,他引:16
据沉积,构造、地貌并结合地球物理资料综合研究认为,秦岭造山带新生代构造隆升是在中生代白垩纪晚期构造隆升基础上,于晚第三纪中新世迅速隆升,而早更新世早期则是新构造活动最强烈时期。秦岭造山带的新生代构造隆升的方式主要有地垒式、掀斜式、振荡式和翘板式4种。诱发这一地区新构造抬升的主要原因和动力学机制是华北地块自北而南,扬子地块自南而北相向向秦岭造山带之下陆内俯冲和秦岭地块深部软流圈抬升共同作用所致。 相似文献
86.
Environmental and legal aspects of karst areas 总被引:3,自引:0,他引:3
Environmental impacts on karst settings are common as they are more sensitive than those of other rock terrains. Regulatory
procedures that are effective in other rock terrains are not necessarily applicable to karst settings. Development and exploitation
by man that affect the karst hydrology regime can trigger catastrophic events and result in numerous legal actions where the
effects of changes go beyond property boundaries. A great variety of regulations and examples of litigation exist for karst
areas.
Received: 25 October 1994 · Accepted: 17 October 1995 相似文献
87.
磁学方法在环境污染研究中的应用 总被引:12,自引:0,他引:12
环境磁学方法问世20多年来,因其快速、灵敏、经济、无破坏性和信息量大的特点,在环境研究中得到广泛的应用。磁学方法可用于传统的污染分析技术(化学)之前的预研究,而后者一般耗费大量人力、物力和时间;它也可以作为环境污染评估的代用指标。近年来,随着世界环境污染问题的日益严重和倍受关注,磁学方法被广泛地应用于环境污染研究。欧洲环境磁学专家在重建污染历史、监测现代环境污染、追踪与分离污染源等方面,开展了大量的工作,并积累了一定的经验。介绍了磁学方法用于污染研究的显著特点、主要用途、野外工作方法以及相关仪器;展示了在大气、土壤、潮滩、河流、湖泊以及海洋等不同环境系统中,利用磁手段研究污染的成果和最新进展;对
于一些难点、热点问题,如磁性机理的研究、多源污染的分离、强烈多变的人类活动对获取有意义磁讯号的影响等,做了相应的分析和总结。 相似文献
88.
A. Douaik M. van Meirvenne T. Tóth M. Serre 《Stochastic Environmental Research and Risk Assessment (SERRA)》2004,18(4):219-227
The mapping of saline soils is the first task before any reclamation effort. Reclamation is based on the knowledge of soil salinity in space and how it evolves with time. Soil salinity is traditionally determined by soil sampling and laboratory analysis. Recently, it became possible to complement these hard data with soft secondary data made available using field sensors like electrode probes. In this study, we had two data sets. The first includes measurements of field salinity (ECa) at 413 locations and 19 time instants. The second, which is a subset of the first (13 to 20 locations), contains, in addition to ECa, salinity determined in the laboratory (EC2.5). Based on a procedure of cross-validation, we compared the prediction performance in the space-time domain of 3 methods: kriging using either only hard data (HK) or hard and mid interval soft data (HMIK), and Bayesian maximum entropy (BME) using probabilistic soft data. We found that BME was less biased, more accurate and giving estimates, which were better correlated with the observed values than the two kriging techniques. In addition, BME allowed one to delineate with better detail saline from non-saline areas. 相似文献
89.
Ali Kahriman 《Soil Dynamics and Earthquake Engineering》2004,24(11):887-892
The aim of this study is to predict peak particle velocity level at a limestone quarry located in Istanbul, Turkey. The ground vibration components were measured for 73 blast events during the bench blast optimization studies during a long period. In blasting operations; ANFO (blasting agent), gelatine dynamite (priming) and NONEL detonators (firing) were used as explosives at this site. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured by means of vibration monitors for every event. Then, the data pairs of scaled distance and particle velocity were analyzed. The equation of scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity. At the end of statistical evaluations, an empirical relationship with good correlation was established between peak particle velocity and scale distance for this site. The established relationship and the results of the study are presented. 相似文献
90.
Sergio Colombo Mario Chica-Olmo Francisco Abarca Hugh Eva 《ISPRS Journal of Photogrammetry and Remote Sensing》2004,58(5-6):330-341
Tropical forest mapping is one of the major environmental concerns at global and regional scales in which remote sensing techniques are firmly involved. This study examines the use of the variogram function to analyse forest cover fragmentation at different image scales. Two main aspects are considered here: (1) analysis of the spatial variability structure of the forest cover observed at three different scales using fine, medium and coarse spatial resolution images; and (2) the study of the relationship between rescaled images from the finest spatial resolution and those of the medium and coarse spatial resolutions. Both aspects are analysed using the variogram function as a basic tool to calculate and interpret the spatial variability of the forest cover. An example is presented for a Brazilian tropical forest zone using satellite images of different spatial resolutions acquired by Landsat TM (30 m), Resurs MSU (160 m) and ERS ATSR (1000 m). The results of this study contribute to establishing a suitable spatial resolution of remotely sensed data for tropical forest cover monitoring. 相似文献