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1.
土壤盐渍化是新疆最常见的土地退化过程,已经严重威胁到了当地的农业生产、生态稳定和经济发展。通过对渭库绿洲土壤含盐量和土壤热红外光谱分析,探讨了土壤含盐量与热红外发射率之间的定量关系。结果表明：（1）盐渍化土壤的发射率随着含盐量的变化而发生变化,当土壤盐分增加时,发射率也随之增大。（2）土壤含盐量与热红外发射率光谱数据相关性在8.5～9.5 μm波段范围内表现尤为显著,相关系数超过0.8,最高为0.90,对应波段范围9.259～9.271 μm。（3）运用回归模型一阶导数变换形式下建模效果和预测精度都是最优的,R2达到了0.899,RMSE最小为1.734。热红外光谱技术可以反演土壤含盐量,为利用热红外遥感识别土壤盐分信息提供技术支撑。 相似文献
2.
遥感对地观测为理解陆地植被动态与全球环境变化规律提供了数据基础,基于卫星观测的全球植被遥感数据产品近年来层出不穷,但缺乏基于数据使用者视角的系统梳理。本文回顾了全球植被遥感数据产品的发展历程,梳理了相关卫星计划及对应数据产品,分析了从植被光谱指数到生物物理特征参量、传统光学遥感反演到叶绿素荧光及星载微波反演产品、从单一传感器生产到多数据源—多数据集融合产品的发展脉络,阐述了全球植被遥感数据产品的来源、特征与关联关系。认为当前全球植被遥感数据产品的生产与应用存在一定脱节,遥感产品精度制约了对地球系统的深入理解。全球植被遥感数据产品正从宏观状态监测向专业化、精细化、标准化转变,建议未来制备全球遥感数据产品应充分利用目前已积累的长时序观测数据,融合多源观测资料,提升现有数据集的时空分辨率、精度及连续性;注重提高特殊区域与特定类型生态系统的反演精度,加强多维植被特征的一体化监测;建立全球植被产品数据共享平台,提供标准的全流程数据处理与分发服务,将数据不确定性信息高效、清晰提供给用户。 相似文献
3.
G. GRAY TAPPAN DONALD G. MOORE WALTER I. KNAUSENBERGER 《International journal of geographical information science》2013,27(1):123-135
Abstract Development programmes in Sahelian Africa are beginning to use geographic information system (GIS) technology. One of the GIS and remote sensing programmes introduced to the region in the late 1980s was the use of seasonal vegetation maps made from satellite data to support grasshopper and locust control. Following serious outbreaks of these pests in 1987, the programme addressed a critical need, by national and international crop protection organizations, to monitor site-specific dynamic vegetation conditions associated with grasshopper and locust breeding. The primary products used in assessing vegetation conditions were vegetation index (greenness) image maps derived from National Oceanic and Atmospheric Administration satellite imagery. Vegetation index data were integrated in a GIS with digital cartographic data of individual Sahelian countries. These near-real-time image maps were used regularly in 10 countries for locating potential grasshopper and locust habitats. The programme to monitor vegetation conditions is currently being institutionalized in the Sahel. 相似文献
4.
植物物候遥感监测精度影响因素研究综述 总被引：5，自引：1，他引：4
基于植物物候的遥感监测对于研究植被对气候变化的响应具有重要的科学价值。本文在阐述植物物候遥感监测原理及其通用技术流程的基础上,分别从植被类型及其所处的地理条件、遥感数据源及其预处理、植物物候遥感识别方法和植物物候遥感监测结果评价4个方面分析了影响植物物候遥感监测精度的因素,并针对当前研究中存在的不足,探讨了提高植物物候遥感监测精度的可行性途径,即建立高分辨率的近地面遥感定点观测及数据共享网络,发展普适性更强的卫星遥感时序数据去噪及植被指数曲线重建方法,寻求稳定性更高的植物物候期遥感识别方法,探索综合运用地面观测、遥感监测与模型模拟实现物候观测空间尺度拓展的可能性。 相似文献
5.
GRAPES-SDM沙尘模式和卫星遥感监测是目前沙尘暴监测预报业务中重要的工具.本文使用天气学检验方法,对中国气象局兰州干旱气象研究所目前使用的GRAPES-SDM沙尘模式2012年春季沙尘天气预报情况以及FY-2D卫星遥感产品沙尘指数IDDI的监测效果进行检验评估.结果表明:沙尘模式在西北沙尘暴预报业务中具有很好的预报参考价值,卫星遥感沙尘指数也具有较好的监测效果,但两者均存在一定的问题.沙尘模式对大范围沙尘暴过程有较好的预报能力,但对沙尘强度预报偏强;卫星遥感沙尘指数虽然不能定性地表示沙尘强度,但是在一定程度上能够反映沙尘强度的变化,不过反映沙尘强度的数值及其分布区间还有待于进一步完善.卫星遥感在南疆盆地常会将大片深厚的沙尘气溶胶区域误判为云区,造成对沙尘天气特别是沙尘暴天气未能识别的现象,另外IDDI指数不能用于夜间沙尘监测. 相似文献
6.
The effects of armed conflict on cities constitute a large field of research in both conflict studies and urban studies. The topic of urban expansion is also explored by the domain of remote sensing, a sub-branch of geoinformation science. Remote sensing researchers analyze the spatial development of cities in conflict and non-conflict environments using satellite imagery.However, a dialogue or collaboration between these disciplines is virtually non-existent in the scientific discourse, mainly due to stark differences in their methodologies – namely, intensive on-the-ground field research in the case of conflict and urban studies and highly elaborate computer-based analysis of remotely-gathered data in the case of remote sensing.We aim to demonstrate a simple and thus feasible approach for the use of satellite imagery by non-experts of remote sensing, to add a spatio-temporal dimension to the results of in-depth field studies. We apply our approach to the city of Goma, in the eastern region of the Democratic Republic of the Congo, which is located at the center of protracted armed conflict that has raged for decades. With the support of local knowledge acquired during field visits, we visually analyze a time series of Landsat data and add our own results to those of existing research. Contextualizing the mapped results of Goma's urban expansion between 1986 and 2015, we show how urban growth is linked to particular waves of forced displacement caused by different stages of armed conflict and one particular natural disaster. 相似文献
7.
基于GF-1影像的洞庭湖区水体水质遥感监测 总被引：1，自引：0，他引：1
湖泊水质监测是有效开展湖泊水环境综合管理与水污染防治实施的基础,也是湖泊藻华风险评估与生态安全建设的重要依据。本文基于GF-1号影像对2014-2016年洞庭湖水体的叶绿素a浓度、悬浮物浓度和透明度展开遥感监测,结果表明：叶绿素a主要集中在水流速度较慢的安乐湖、大小西湖和东洞庭湖西部地区,其他区域水体扰动力大,叶绿素含量a较低。透明度从北到南递增,与悬浮物浓度的分布趋势相反,符合常规监测规律。东洞庭湖水质较南洞庭湖和西洞庭湖差,水污染程度处于全湖最高水平。GF-1数据可精确反映叶绿素a浓度、悬浮物浓度和透明度指数的空间变化规律,也为后续高分遥感影像湖泊水质监测的应用研究提供了重要参考。 相似文献
8.
年度监测是及时掌握荒漠化动态的有效方法。以MODIS卫星影像为数据源,依据荒漠化土地特征和荒漠化遥感监测指标选取原则,选取了能够基于中低分辨率MODIS卫星数据反演的4个遥感监测指标,将原国家林业局第三次荒漠化监测结果与MODIS反演的4个遥感监测指标的栅格图进行叠加,参照各监测指标在不同荒漠化程度等级下的像元值,得到各指标荒漠化程度判别值。根据原国家林业局荒漠化监测气候分区规定,基于各监测指标判别值,应用决策树分类方法,实现了中国不同气候区域2001-2017年的荒漠化状况年度监测。以2009年原国家林业局第四次中国荒漠化土地监测结果与本文年度监测结果对比,吻合度达92.62%。 相似文献
9.
无人机遥感在红树林资源调查中的应用 总被引：6，自引：0，他引：6
低空无人机（UAV,Unmanned Aerial Vehicles）遥感系统具有数据采集灵活、低成本且可快速获取超高分辨率影像的特色,是传统航空遥感和卫星遥感的重要补充。以广东省和广西壮族自治区交界处的英罗港港湾两侧为研究区域,将无人机遥感系统用于红树林资源的遥感调查,通过无人机航拍获取高分辨率影像,并且使用拼接的影像和目视解译方法提取红树林空间分布信息,进一步选择典型研究样地,采用面向对象的最近邻分类方法对红树林树种类型进行分类研究,并对比综述了无人机遥感和常规航空航天遥感技术对红树林资源调查监测的优缺点,无人机遥感系统非常适用于红树林资源调查。通过2 h 30 min的3架次无人机航飞工作,获取了研究区域25.29 km2的无人机影像,基于无人机影像和面向对象遥感分类方法提取的红树林空间分布信息精度超过了90%。未来无人机遥感系统将可成为调查和监测红树林资源的重要技术手段,可为相关管理部门对红树林资源的保护、管理、开发等方面的工作提供基础信息和技术支持。 相似文献
10.
《The Journal of geography》2012,111(2):75-79
Abstract Easier access to submeter imagery has fueled debates over ethical uses of remote sensing. Some have called for ethics instruction to counter undesired uses of the technology. Here, this article reports the results of a survey examining attitudes related to teaching ethics in remote sensing. It was found that 52 percent of respondents teaching remote sensing include ethical use discussions. Agreement on the importance of ethics instruction is statistically associated with the year the instructor received their degree, the highest degree awarded by their department, the number of remote sensing courses offered at their institution, and their prior exposure to ethical debates in remote sensing. 相似文献
11.
内陆水体水质参数光谱特征与定量遥感 总被引：2，自引：0，他引：2
该文在分析内陆水体及其主要水质参数的光谱特征的基础上 ,讨论了水质遥感监测常用的遥感数据和方法 ,对近年来国内外遥感技术特别是高光谱技术在内陆水体水质监测中的应用研究现状和进展进行了综述 ,并提出未来此领域的发展方向及研究工作的重点 相似文献
12.
应用遥感技术探测土壤侵蚀的研究进展 总被引：1，自引：1，他引：0
在全世界范围内土壤侵蚀对农业生产和水质量都有着负面影响, 因此区域尺度的土壤侵 蚀评估非常重要, 但是它往往会受可收集到观测数据的数量和质量的限制。在过去的30 年中, 遥 感技术已为土壤侵蚀研究提供了多方面有效空间数据, 这些数据常被直接用于探测土壤侵蚀和 土壤侵蚀沉积, 通过辨别土壤侵蚀的总体特征, 可以区分土壤侵蚀区域, 再根据经验评估土壤侵 蚀强度, 获得探测结果。本文介绍了可用于土壤侵蚀研究的多种卫星和传感器及应用遥感数据探 测土壤侵蚀特征, 土壤侵蚀区域和土壤侵蚀沉积的实例。 相似文献
13.
Freshwater environments in New Zealand provide a range of ecosystem services and contain important biodiversity. Managing these environments effectively requires a comprehensive inventory of the resource and cost-effective tools for regular monitoring. The complex and extensive margins of natural water bodies make them difficult to sample comprehensively. Problems thus occur with extrapolating point-specific sampling to accurately represent the diversity of vegetation in large freshwater bodies. Mapping freshwater vegetation using satellite remote sensing can overcome problems associated with access, scale and distribution, but it requires high-resolution images that have appropriate spectral characteristics. This paper provides an overview of the optical satellite data characteristics required for mapping riparian, submerged and emergent vegetation associated with freshwater environments in New Zealand. 相似文献
14.
干旱区农作物长势综合监测 总被引：17，自引：2，他引：17
大面积农作物生长状况的监测是一个比较复杂的问题 ,目前还没有较为成熟的办法。我国已经完成和正在开展的农作物遥感监测与估产主要是在华北平原和东北平原等大面积农作物种植区 ,而西北内陆特别是新疆这样的耕地零星分布、具有特殊的地理环境和气候特点的地区 ,很少有人涉足这方面的研究。本文以遥感信息为主 ,在地理信息系统和全球定位系统的支持下 ,以新疆北部为实验区 ,通过对相邻年份归一化植被指数 (NDVI)的对比 ,结合野外调查与历史产量的分析 ,实现大面积农作物长势监测。该方法将遥感技术的宏观快速、地理信息系统的信息管理和空间分析以及全球定位系统的精确定位监测有机地结合起来 ,取得良好的应用效果。 相似文献
15.
Tropical forest monitoring and remote sensing: A new era of transparency in forest governance? 总被引：3，自引：0，他引：3
Douglas O. Fuller 《Singapore journal of tropical geography》2006,27(1):15-29
The extent of tropical deforestation is now being tracked by actors in the nongovernmental, academic, private and government sectors using several different sources of satellite imagery. This paper presents an overview of the satellite systems that can be used for operational forest monitoring in the tropics and examines some recent trends in their use. It also reviews various satellite-based studies to map moist tropical forests and draws upon lessons learned from land cover mapping projects in several countries and regions. The case of Indonesia, examined as a nation undergoing rapid conversion of forest to other land uses, is contrasted with Brazil where satellite-based deforestation monitoring is fully operational. In Indonesia, the paper argues, the creation of a national monitoring system for tropical forest conversion is needed to create a source of transparent, reliable information on forest cover and condition. Such a system is likely to succeed if based on multitemporal, moderate-resolution optical data such as imagery provided by MODIS (Moderate Resolution Imaging Spectrometer). When MODIS images are complemented by radar and fine-resolution imagery from sensors such as IKONOS and QuickBird, areas of abrupt change can be identified and the causes potentially discerned. Thus, satellite imagery at multiple temporal and spatial resolutions can effectively increase transparency in the forestry sector by revealing the rate and extent of deforestation on an annual basis and identifying potential areas of illegal logging. 相似文献
16.
新疆荒漠地区植被覆盖度遥感估算模型十分缺乏,给荒漠化监测等相关工作带来很大不便,开展植被覆盖度遥感估算经验模型研究,对于促进和完善相关地区的生态监测及研究工作具有积极的现实意义。通过对阜康市北部沙漠南缘和克拉玛依市中部平原荒漠进行无人机航拍,利用无人机遥感提取（光合）植被信息,并将无人机航拍影像的植被覆盖度统计单元与高分辨率卫星影像像元在空间上直接相对应,获取在高分辨率卫星影像像元尺度上的植被盖度,然后通过植被覆盖度和空间上与其相对应的源自高分辨率卫星影像的NDVI数据的拟合关系,建立基于源自高分二号影像的NDVI的阜康北部沙漠植被覆盖度遥感估算线性模型以及基于源自ZY1-02C影像的NDVI的克拉玛依平原荒漠植被覆盖度遥感估算二次多项式模型。研究中所采用的无人机遥感与卫星遥感相结合、植被覆盖度统计单元与卫星像元在空间上直接对应的方法,可避免以往相关工作中常以点位测量数据代表卫星像元数据所带来的不确定性。由于所用卫星影像的NDVI数据稳定性相对不足等原因,所建立的遥感估算模型的估算精度尚相对偏低,有待于今后进一步的工作加以改进。 相似文献
17.
黄河三角洲刁口河流路湿地恢复遥感监测与评价 总被引：1，自引：0，他引：1
利用卫星遥感技术对生态调水及湿地恢复进行实时动态监测, 不仅可以及时掌握宏观地表的快速变化, 还可以为长期的区域生态效应评价提供支持。基于国产自主环境一号小卫星遥感数据, 对2010 年黄河三角洲生态调水暨刁口河流路恢复过水试验进行动态监测和初步评价。研究表明, 刁口河流路恢复过水后, 原废弃河道过流条件得到提高, 部分被开发利用的河滩地得到恢复, 水文条件好转, 河流水面面积总体上增加了526 hm2, 有利于河道生态条件的改善。通过对湿地引水修复, 自然保护区试验区块共有437 hm2的退化湿地得到了较大程度的改善。同时, 湿地景观多样性提高, 对维持区域景观多样性、改善鸟类栖息地质量具有重要意义。研究结果表明, 国产环境一号卫星遥感数据能提供丰富的地面信息, 其数据具有较高的时间分辨率, 可以作为中国湿地调查和监测的重要数据源。考虑到大尺度调水和湿地恢复对区域生态环境的影响是一个长期的过程, 今后应进一步挖掘环境一号卫星现有波段的光谱信息, 对湿地恢复进行长期跟踪监测, 为湿地恢复生态效应综合评估提供技术支撑。 相似文献
18.
As the world becomes increasingly urbanized, the need for fresh fruits and vegetables in urban areas grows while the difficulty of bringing these perishable products to these areas also increases. Small-scale agriculture located in urban areas is a highly effective and profitable way to provide these products to communities that are far from extensive commercial agricultural areas. Here we describe how remote sensing can be used with data mining approaches to monitor urban and peri-urban farms within cities in both developed and developing countries. Using very high resolution satellite imagery together with moderate and coarse resolution imagery and information from social media and the web, we analyze the usefulness of different methods to identify farms within urban boundaries in four countries. The analysis shows how a mixed-method approach is necessary in order to identify where urban farming is occurring and to monitor its change through time. Although remote sensing-based vegetation and water indices were useful, without ancillary data they are not effective at remotely mapping the locations of urban farms. However, remote sensing is a good way to monitor vegetation condition in locations where actively managed urban farms are known to exist. 相似文献
19.
土壤盐渍化严重制约土地生产力,实时监测土壤盐渍化有利于农业正常生产。选择新疆渭干河—库车河绿洲的光谱反射率数据,研究不同程度盐渍化土壤的光谱特征;并对绿洲所在的库车县的环境与灾害监测预报小卫星的高光谱数据进行盐渍化信息提取。提取步骤为：首先对土壤光谱反射率数据进行14种形式的变换,再与土壤含盐量进行相关分析、逐步回归分析,建立估算不同盐渍化程度的土壤含盐量方程,用均方根误差验证方程的精度;其次,建立植被和土壤波谱库;最后,在波谱库的数据基础上,使用波谱角分类法（SAM）对环境与灾害监测预报小卫星的高光谱数据进行分类。用同步实测数据对分类效果进行精度评价,效果较好,这一结果为今后该区域的高光谱应用奠定了基础,对区域农民耕作方式提出了警示,为区域可持续发展实践提供了参考。 相似文献
20.
Jan-Gunnar Winther Oddbjørn Bruland Knut Sand Sebastian Gerland David Marechal Boris Ivanov Piotr Gøowacki Max König 《Polar research》2003,22(2):125-144
This paper summarizes the most significant snow-related research that has been conducted in Svalbard. Most of the research has been performed during the 1990s and includes investigations of snow distribution, snow-melt, snow pack characteristics, remote sensing of snow and biological studies where snow conditions play an important role. For example, studies have shown regional trends with about 50% higher amounts of snow accumulation at the east coast of Spitsbergen compared to the west coast. Further, the accumulation rates are about twice as high in the south compared to the north. On average, the increase in accumulation with elevation is 97 mm water equivalents per 100 m increase in elevation. Several researchers reported melt rates, which are primarily driven by incoming short-wave radiation, in the range of 10-20 mm/day during spring. Maximum melt rates close to 70 mm/day have been measured. In addition to presenting an overview of research activities, we discuss new, unpublished results in areas where considerable progress is being made. These are i) modelling of snow distribution, ii) modelling of snowmelt runoff and iii) monitoring of snow coverage by satellite imagery. We also identify some weaknesses in current research activities. They are lacks of i) integration between various studies, ii) comparative studies with other Arctic regions, iii) applying local field studies in models that can be used to study larger areas of Svalbard and, finally, iv) using satellite remote sensing data for operational monitoring purposes. 相似文献