共查询到20条相似文献,搜索用时 93 毫秒
1.
农村黑臭水体治理是改善农村人居环境的一项非常重要的内容,黑臭水体识别是黑臭水体治理的前提和基础。本文在反射率光谱指数BOI(Black and Odorous water Index)的黑臭水体识别模型基础上,结合省基础测绘数据、高分辨率数字正射影像等专题资料,提出了基于高分一号(GF-1)遥感影像的农村黑臭水体识别模型,能够初步判别农村黑臭水体分布情况,为快速获取农村黑臭水体空间位置提供了解决方案,在农村黑臭水体治理中具有一定的应用价值。 相似文献
2.
高分辨率卫星的幅宽一般很小,受云雨和轨道回访周期影响,单颗卫星的短时段内覆盖能力有限,因此,单一高分辨率卫星常常无法满足一定时段内的黑臭水体监测需求,需要多源卫星协同监测黑臭水体。为了分析多源高分辨率影像对黑臭水体遥感监测的适用性,本文基于地物光谱仪实测的水体遥感反射率数据,以GeoEye-1、WorldView-2、北京二号(DMC3)、高景一号SV1(SuperView-1)以及GF-PMS系列(GF-1/1B/1C/1D、GF-2、GF-6)传感器波段进行等效计算,结果表明:(1)采用反射率比值模型——BOI(Black and Odorous water Index)模型,GeoEye-1、WorldView-2、SuperView-1和GF-1/1B/1C/1D/2/6影像识别黑臭水体正确率均较高,分别为89.5%、89.5%、92.1%和92.1%。(2)BOI模型不适用于DMC3,这里采用了归一化水体指数NDWI≤0.55判别黑臭水体,识别正确率为89.5%。(3)BOI模型应用于仅有的2景同步卫星影像——GF-2影像,经实测数据验证,识别精度为83.3%,精度较高。针对通州区内的某重叠区,2016年—2021年10颗多源卫星影像协同观测的结果一致性较好,表明了多源遥感影像监测黑臭水体的适用性较好。综合考虑卫星影像空间分辨率和采购成本,给出了合理的协同观测建议。 相似文献
3.
太原市黑臭水体遥感识别与地面验证 总被引:2,自引:1,他引:1
城市黑臭水体整治是城市水环境治理的一项重要工作。本文通过构建黑臭水体遥感识别模型,解决城市黑臭水体整治过程中黑臭水体的识别问题,实现城市黑臭水体空间分布快速定位与排查。通过分析黑臭水体形成机理和试验数据,从光谱特征上构建反映水体清洁程度的光谱指数(WCI),从图像特征上构建水体颜色、次生环境、河道淤塞、岸边带垃圾堆放等解译标志,综合光谱指数和解译标志共同进行黑臭水体遥感识别。利用该方法对太原市建成区内黑臭水体空间分布进行排查识别,共得到疑似黑臭河段14条,长度为52.530 km。经验证,除去断流影响外,遥感识别黑臭水体点位精度为92.86%,遥感识别黑臭河段长度精度为78.19%。在精度验证基础之上,进一步分析了黑臭水体遥感识别光谱指数和各项解译标志在黑臭识别中所占的权重,其中光谱指数和水体颜色二者权重最大,分别占29.60%和27.10%,是构成遥感识别黑臭水体的主要特征标志。通过两时相影像识别结果比对表明,WCI指数能够明显反应黑臭水体变化特征。因此,利用本文方法进行城市黑臭水体遥感识别具有很高的精度,在城市水环境整治过程中具有重要的应用价值。 相似文献
4.
5.
《国土资源遥感》2021,(1)
目前,城市黑臭水体的遥感识别处于算法初探阶段,由于受到水深、阴影等因素的影响,在实际应用中精度较低,并且对于长时间的黑臭水体动态监测研究较少。以芜湖鸠江区为研究区,分析黑臭水体的成因及表观特征,针对单波段阈值法、波段差值法、归一化指数法和斜率指数法,基于GF-2影像进行阈值修正并评价精度,同时联合黑臭水体目视解译标志进行动态监测。结果表明:(1)水体发生黑臭通常伴有颜色异常、河道淤塞、次生环境问题等特征;(2)单一识别算法中差值法识别效果最好,总精度为87.5%;(3)GF-2的高空间分辨率特性提升了目视解译的效率和精度,可以有效减少水深和建筑物阴影对其遥感识别的干扰,相比使用单一算法,进一步提高了动态监测的识别精度和可靠性;(4)利用2014—2020年4景GF-2影像提取鸠江区主城区黑臭水体面积分别为0.313 km~2,0.152 km~2,0.069 km~2和0.008 km~2。结果显示,鸠江区水体黑臭现象正逐步得到改善,但神山公园水系黑臭现象依然严重。 相似文献
6.
基于谱间关系的MODIS遥感影像水体提取研究 总被引:10,自引:0,他引:10
水是地球上万物的命脉所在,水体提取对于水资源调查、洪水灾害预测评估和环境监测等有着重要作用。而可见光和近红外波段水体与植被、城市和土壤光谱反射率的差异是利用遥感手段提取水体的基本原理。本文利用谱间关系法进行MOD IS图像的水体提取。结果表明,用于提取水体的谱间关系法比归一化植被指数(NDVI)法快速,但谱间关系法有把云错误地当作水体提取的缺点。 相似文献
7.
8.
9.
10.
大气程辐射遥感图像与城市大气污染监测研究 总被引:3,自引:0,他引:3
作为对地探测的遥感技术所获取的遥感图像包含了地面和大气信息,并且主要是地面信息.利用地面反射率分布图像将遥感数字图像中弱的大气信息与强的地面目标信息分离,生成仅仅包含大气信息的大气程辐射遥感图像.利用多(高)光谱遥感数字图像中不同波段的大气程辐射遥感图像可以不受地面干扰地对城市大气污染的类型和程度(气溶胶粒径和含量)进行遥感监测.在大气污染地面观测数据(可吸入颗粒物PM10浓度)的支持下,利用MODIS多光谱遥感数字图像生成的对应多光谱大气程辐射遥感数字图像,以上海市为例进行了城市大气污染遥感监测的原理方法研究. 相似文献
11.
吕志慧 《测绘与空间地理信息》2016,(5):179-181
随着南京市水利信息化建设工作的推进,各水利管理部门根据各自部门的业务需求开发建设了部分水利业务系统,但缺乏统一的技术标准、数据基础,建设的系统不能实现数据、功能的共建共享,制约了水利信息化建设。因此,基于统一基础地理数据、标准地理信息服务技术的水利地理信息系统的实现,可以为各类水利地理信息的集成共享管理、全市水利信息化的建设提供更为行之有效的技术支撑。 相似文献
12.
Spatial and temporal resolution of water vapor content is useful in improving the accuracy of short-term weather prediction. Dense and continuously tracking regional GPS arrays will play an important role in remote sensing atmospheric water vapor content. In this study, a piecewise linear solution method was proposed to estimate the precipitable water vapor (PWV) content from ground-based GPS observations in Hong Kong. To evaluate the solution accuracy of the water vapor content sensed by GPS, the upper air sounding data (radiosonde) that are collected locally was used to calculate the precipitable water vapor during the same period. One-month results of PWV from both ground-based GPS sensing technique and radiosonde method are in agreement within 1–2 mm. This encouraging result will motivate the GPS meteorology application based on the establishment of a dense GPS array in Hong Kong. 相似文献
13.
Spatial and temporal resolution of water vapor content is useful in improving the accuracy of short-term weather prediction.Dense and continuously tracking regional GPS arrays will play an important role in remote sensing atmospheric water vapor content.In this study,a piecewise linear solution method was proposed to estimate the precipitable water vapor (PWV) content from ground-based GPS observations in Hong Kong.To evaluate the solution accuracy of the water vapor content sensed by GPS,the upper air sounding data (radiosonde) that are collected locally was used to calculate the precipitable water vapor during the same period.One-month results of PWV from both ground-based GPS sensing technique and radiosonde method are in agreement within 1~2 mm.This encouraging result will motivate the GPS meteorology application based on the establishment of a dense GPS array in Hong Kong. 相似文献
14.
地基GPS技术遥感香港地区大气水汽含量 总被引:3,自引:0,他引:3
提出了分段多项式方法计算大气水汽含量,并结合无线电高空气象探测资料,分析并评估了地基GPS遥感技术的精度。香港地区的可降水份计算结果表明,地基GPS遥感技术的精度为1 m m ~2 m m 相似文献
15.
Daniel J. Foley Itiya P. Aneece Pardhasaradhi G. Teluguntla Adam J. Oliphant 《International Journal of Digital Earth》2020,13(8):939-975
ABSTRACT The overarching goal of this study was to perform a comprehensive meta-analysis of irrigated agricultural Crop Water Productivity (CWP) of the world’s three leading crops: wheat, corn, and rice based on three decades of remote sensing and non-remote sensing-based studies. Overall, CWP data from 148 crop growing study sites (60 wheat, 43 corn, and 45 rice) spread across the world were gathered from published articles spanning 31 different countries. There was overwhelming evidence of a significant increase in CWP with an increase in latitude for predominately northern hemisphere datasets. For example, corn grown in latitude 40–50° had much higher mean CWP (2.45?kg/m³) compared to mean CWP of corn grown in other latitudes such as 30–40° (1.67?kg/m³) or 20–30° (0.94?kg/m³). The same trend existed for wheat and rice as well. For soils, none of the CWP values, for any of the three crops, were statistically different. However, mean CWP in higher latitudes for the same soil was significantly higher than the mean CWP for the same soil in lower latitudes. This applied for all three crops studied. For wheat, the global CWP categories were low (≤0.75?kg/m³), medium (>0.75 to <1.10?kg/m³), and high CWP (≥1.10?kg/m³). For corn the global CWP categories were low (≤1.25?kg/m³), medium (>1.25 to ≤1.75?kg/m³), and high (>1.75?kg/m³). For rice the global CWP categories were low (≤0.70?kg/m³), medium (>0.70 to ≤1.25?kg/m³), and high (>1.25?kg/m³). USA and China are the only two countries that have consistently high CWP for wheat, corn, and rice. Australia and India have medium CWP for wheat and rice. India’s corn, however, has low CWP. Egypt, Turkey, Netherlands, Mexico, and Israel have high CWP for wheat. Romania, Argentina, and Hungary have high CWP for corn, and Philippines has high CWP for rice. All other countries have either low or medium CWP for all three crops. Based on data in this study, the highest consumers of water for crop production also have the most potential for water savings. These countries are USA, India, and China for wheat; USA, China, and Brazil for corn; India, China, and Pakistan for rice. For example, even just a 10% increase in CWP of wheat grown in India can save 6974 billion liters of water. This is equivalent to creating 6974 lakes each of 100?m³ in volume that leads to many benefits such as acting as ‘water banks’ for lean season, recreation, and numerous ecological services. This study establishes the volume of water that can be saved for each crop in each country when there is an increase in CWP by 10%, 20%, and 30%. 相似文献
16.
水汽标高是一个反映水汽垂直分布特征的参数,也是全球导航卫星系统(global navigation satellite system,GNSS)对流层天顶湿延迟改正和GNSS水汽层析中的一个辅助参数。本文对2006—2012年水汽标高的时间序列进行频谱分析,发现水汽标高在时间上呈现出年周期和半年周期变化,因此利用包含年周期和半年周期的三角函数来表达水汽的时变规律,然后利用欧洲中尺度天气预报中心(European Centre for Medium-range Weather Forecasting,ECMWF)的数据在全球1°×1°的格网点上分别拟合了三角函数的系数。通过上述方法首次构建了一个全球适用的水汽标高模型GSH,该模型既体现了水汽标高的时变特性又考虑了其地理差异。以无线电探空数据为参考,GSH具有-0.19km的偏差(bias)和1.81km的均方根误差(root mean square error,RMSE);以ECMWF数据为参考,GSH具有0.04km的bias和1.52km的RMSE。GSH整体上表现出了比较稳定的精度,可服务于GNSS气象学研究,也可为其他相关气象研究提供水汽标高参考。 相似文献
17.
水质遥感监测方法的探讨 总被引:1,自引:0,他引:1
不同水质具有不同的光谱特征,可以利用遥感技术对水质进行监测.水质监测结果是水质评价与水污染防治的主要依据,随着水体污染问题的日渐严重,水质监测成为社会经济可持续发展必须解决的重大问题,无论内陆水体还是海洋水体,其水质影响到国民生产和人们的生活用水,准确、快捷的水质监测显得尤为重要.水质遥感监测具有监测范围广、速度快、成本低和便于进行长期动态监测的特殊优势,在水体水质监测中具有巨大的应用潜力.本文主要对水质遥感监测方法进行探讨. 相似文献
18.
19.