共查询到10条相似文献,搜索用时 48 毫秒
1.
基于典型时段骆马湖LandsatTM遥感影像,利用归一化植被指数(NDVI)法对骆马湖水生植被进行分级研究.采用标准差分级方法,将骆马湖水生植被分为5个等级.研究结果表明,利用这种分级方法处理的图像能够较准确地反映骆马湖水生植被区域分布和等级分区,能够更准确地给出采砂区和生态保护区域的位置,增强湖区水生态环境保护工作的有效性和针对性. 相似文献
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Alparslan E Aydöner C Tufekci V Tüfekci H 《Environmental monitoring and assessment》2007,135(1-3):391-398
Water quality at Omerli Dam, which is a vital potable water resource of Istanbul City, Turkey was assessed using the first four bands of Landsat 7-ETM satellite data, acquired in May 2001 and water quality parameters, such as chlorophyll-a, suspended solid matter, secchi disk and total phosphate measured at several measurement stations at Omerli Dam during satellite image acquisition time and archived at the Marine Pollution and Ecotoxicology laboratory of the Marmara Research Center, where this study was carried out. Establishing a relationship between this data, and the pixel reflectance values in the satellite image, chlorophyll-a, suspended solid matter, secchi disk and total phosphate maps were produced for the Omerli Dam. 相似文献
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以某重金属矿区3个水域(a、b、c)作为研究区,采集Aster卫星传感器的遥感监测数据,再运用分光辐射光谱仪测定标准板与目标水体,计算目标水体的光谱反射率,分析各区域水体遭受重金属污染时的光谱反射特征,实现基于光谱分析的重金属污染废水遥感监测。结果表明:a区域内水体重金属污染程度由深水区向浅水区逐步增强,水体呈现出橙红色;b区域内水体重金属污染程度由浅水区向深水区逐步增强,水体呈现为棕红色;c区域内水体未受到重金属污染,整个区域内水体为铜绿色。该结果与现场采集的各区域水体遭受重金属污染的情况一致。 相似文献
4.
Remote sensing of aquatic vegetation: theory and applications 总被引:2,自引:0,他引:2
Aquatic vegetation is an important component of wetland and coastal ecosystems, playing a key role in the ecological functions
of these environments. Surveys of macrophyte communities are commonly hindered by logistic problems, and remote sensing represents
a powerful alternative, allowing comprehensive assessment and monitoring. Also, many vegetation characteristics can be estimated
from reflectance measurements, such as species composition, vegetation structure, biomass, and plant physiological parameters.
However, proper use of these methods requires an understanding of the physical processes behind the interaction between electromagnetic
radiation and vegetation, and remote sensing of aquatic plants have some particular difficulties that have to be properly
addressed in order to obtain successful results. The present paper reviews the theoretical background and possible applications
of remote sensing techniques to the study of aquatic vegetation. 相似文献
5.
近年来,骆马湖湖区菹草(麦黄草)暴发性繁殖引发了一系列水质问题。通过研究,判读2012—2013年不同时间段的骆马湖landsat 7影像,可以发现,Landsat 7影像可以准确反映湖区菹草分布,区域化明显;同时发现菹草分布受多种因素影响,人类采砂和围网养殖等活动对其影响显著。 相似文献
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Schifter I Díaz L Rodríguez R Durán J Chávez O 《Environmental monitoring and assessment》2008,137(1-3):459-470
A remote sensing study was conducted in year 2006 in four locations of the Metropolitan Area of Mexico City (MAMC). Two of
the sites were the same studied back by us in year 2000 and by others in year 1994. A database was compiled containing 11,289
valid measurements for the carbon monoxide (CO), total hydrocarbons (THC), and nitric oxide (NO) exhaust vehicles emissions.
Valid measurements were binned for each pollutant by the vehicle specific power (between −5 and 20 kW tonne−1) for the 2000 and 2006 databases. The mean average CO, THC, and NO emissions for year 2006 were determined to be 1.10 ± 0.18 vol.%,
299 ± 88.4 ppm, and 610 ± 115.0 ppm, respectively. Matching the vehicle driving patterns of the fleet measured in year 2000
with the emissions factors obtained in this work, allows estimating the trends in the exhaust emissions of vehicles in the
MAMC. The adjusted results of the remote sensing study performed in year 2006 shows that the fleet has decrease 22% in CO
and 17% in NO emissions, with small change in total hydrocarbons emissions. The improvements could be related with the introduction
in year 2001 of vehicles that met tighter emissions standards, particularly for nitrogen oxides. 相似文献
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为研究我国典型滨海湿地环境评价方法,利用卫星遥感技术,结合地面生态调查,构建了以自然湿地面积比例、人工岸线比例等8项因子共同组成的指标体系,通过层次分析法和专家打分法进行权重赋值后,阐述了数据处理和计算的主要流程,提出了滨海湿地环境指数CWEI的概念和表征意义。应用上述方法对江苏盐城湿地珍禽国家级自然保护区进行了典型示范评价,结果表明该方法能够较好地反映滨海湿地环境状况与变化趋势。 相似文献