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381.
This article investigates how remotely sensed lawn characteristics, such as parcel lawn area and parcel lawn greenness, combined with household characteristics, can be used to predict household lawn fertilization practices on private residential lands. This study involves two watersheds, Glyndon and Baisman’s Run, in Baltimore County, Maryland, USA. Parcel lawn area and lawn greenness were derived from high-resolution aerial imagery using an object-oriented classification approach. Four indicators of household characteristics, including lot size, square footage of the house, housing value, and housing age were obtained from a property database. Residential lawn care survey data combined with remotely sensed parcel lawn area and greenness data were used to estimate two measures of household lawn fertilization practices, household annual fertilizer nitrogen application amount (N_yr) and household annual fertilizer nitrogen application rate (N_ha_yr). Using multiple regression with multi-model inferential procedures, we found that a combination of parcel lawn area and parcel lawn greenness best predicts N_yr, whereas a combination of parcel lawn greenness and lot size best predicts variation in N_ha_yr. Our analyses show that household fertilization practices can be effectively predicted by remotely sensed lawn indices and household characteristics. This has significant implications for urban watershed managers and modelers.  相似文献   
382.
Abstract: Arctic lakes are significant emitters of methane (CH4), a potent greenhouse gas, to the atmosphere; yet no rigorous quantification of the magnitude and variability of pan‐Arctic lake emissions exists. In this study, we demonstrate the potential for a new method using synthetic aperture radar (SAR) imagery to detect methane bubbles in lake ice to scale up whole‐lake measurements of CH4 ebullition (bubbling) to regional scales. We estimated ebullition from lakes, which is often the dominant mode of lake emissions, by mapping the distribution of bubble clusters frozen in early winter ice across surfaces of seven tundra lakes and one boreal forest lake in Alaska. Applying previously measured ebullition rates associated with four distinct classes of bubble clusters found in lake ice, we estimated whole‐lake emissions from individual lakes. The percent surface area of lake ice covered with bubbles (R2 = 0.68) and CH4 ebullition rates from lakes (R2 = 0.59) and were correlated with radar return values from RADARSAT‐1 Standard Beam mode 3 for the tundra lakes, suggesting that with appropriate scaling and consideration for variability in lake‐ice conditions, this technique has the potential to be used for estimating broader‐scale regional and pan‐Arctic lake methane emissions.  相似文献   
383.
洪水灾害的遥感监测分析系统研究   总被引:5,自引:1,他引:4  
张金存  魏文秋  马巍 《灾害学》2001,16(1):39-44
给出了洪水灾害的遥感监测分析系统,该系统利用遥感信息资料,应用遥感图像处理软件为主要工具,辅助地理信息,分析洪水水情,确定洪灾量级、危害区域及其土地利用类型等,并可比较真实地再现洪灾场景,为防洪规划提供可靠的辅助决策依据。  相似文献   
384.
Water quality monitoring using remote sensing has been studied in Finland for many years. But there are still few discussions on water quality monitoring using remote sensing technology in support of water policy and legislation in Finland under the WFD. In this study, we present water quality monitoring using remote sensing in the Gulf of Finland, and focus on the spatial distribution of water quality information from satellite-based observations in support of water policy by a case study of nitrate concentrations in surface waters. In addition, we briefly describe instruments using a system of river basin districts (RBD), highlighting the importance of integrated water resources and river-basin management in the WFD, and discuss the role of water quality monitoring using remote sensing in the implementation of water policy in Finland under the WFD.  相似文献   
385.
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   
386.
Understanding the historical dynamics, composition, and environmental disturbances of forest landscapes provides a context for monitoring changes, describing trends, and establishing reference conditions. This study analyses the temporal changes in forest ecosystem structure in Artvin Forest Planning Unit (AFPU), Turkey, during 1972–2002 period based on digitized forest stand type maps using geographic information system (GIS) and interpretation of satellite data. The results showed that there was a net decrease of 450 ha in total forested areas between 1972 and 2002. Forest ecosystem structure changed over time depending on a few factors such as demographic movements, insect outbreaks, dam and road construction, unregulated management actions, and social pressure. In conclusion, temporal changes and the factors affecting these changes should be determined for sustainable management of natural resources.  相似文献   
387.
为加强环境自动监测系统的建设,提供了一个支持多种类型现场信息宽接入的信息采集、支持有线和无线信息传输的开放式在线数据采集传输装置.装置用标准化的工控机作为控制核心,具备模拟信号、LonWorks信号、视频信号、RS-485信号输入接口,网络通信和GPRS远程通信方式,采用Windows操作系统和数据库技术,应用方便灵活,有助于提供有效、客观的现场环境信息,实现环境自动监测与管理.  相似文献   
388.
面对水体富营养化愈来愈严重,水华爆发越来越频繁的严峻形式;为减少水华发生频率及由此造成的损失,开展水华预警已成当务之急。水华爆发是水体中营养盐的累积、气候条件与水力条件等众多因素非线性共同作用的产物;为此,有必要在众多水华影响因素的动态监测信息的融合基础上,寻求水华爆发与这些影响因素间的影射关系,这就需要信息融合技术。通过归纳总结多源信息融合技术在内陆湖库水华预警中应用的研究进展,结合目前我国水华预警的具体需求,提出建立基于多源信息融合技术的水华预警决策支持系统的研究前景与初步设想。信息融合技术为水华预警提供了一个良好的平台,它将与水华相关的不同信息源(水文、气象、水环境质量与环境遥感)所提供的局部不完整的观测信息加以集成与互补,消除多源信息之间存在的冗余和矛盾,形成对水华爆发环境相对完整的感知与描述;从而提高水华预警与应急响应决策的效率,提高预警信息的时间与空间分辨率,扩展信息的时空监测范围。  相似文献   
389.
本文以遥感为技术手段,利用ERl、ASⅢAGINE8.5和FRAGSTATS3.3软件针对项目区在景观总体格局和各类型斑块两个层次计算出十几种景观指数,对该区域的景观格局分布做出了较为全面的定量分析.结果表明:草地景观面积最大,斑块数最多,是评价区的基质.乔木林地在各项指数分析中均较低.文中探讨了遥感与地面调查的优缺点,得出结论:以遥感技术为手段,结合地面调查是评价区域生态环境的有效工具.  相似文献   
390.
河北省海洋灾害遥感动态监测系统简介   总被引:2,自引:0,他引:2  
为及时获取海洋灾害发生及其影响的监测信息,并为当地政府和有关部门提供决策服务,根据渤海湾海洋灾害发生的特点,从风暴潮、赤潮、海冰、海域污染等海洋灾害的遥感监测技术方法研究入手,介绍了河北省海洋灾害遥感动态监测系统的功能。应用服务情况表明,该系统对渤海的风暴潮、赤潮、海冰、海域污染的遥感监测效果良好。重点对利用NOAA/AVHRR数据开展的1998—2006年春季渤海海域污染遥感监测情况进行了客观的分析,结果表明,渤海湾近海水域从1999年开始出现大范围污染,其中,2002年最为严重,2003年以后有所好转,但是近两年的污染状况又趋严重。  相似文献   
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