Monitoring South Florida Wetlands Using ERS-1 SAR Imagery
Monitoring South Florida Wetlands Using ERS-1 SAR Imagery
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DOI：
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发表时间：
1997
影响因子：
1.3
通讯作者：
E. Kasischke;L. Bourgeau-Chavez
中科院分区：
文献类型：
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作者：
E. Kasischke;L. Bourgeau-Chavez
本研究评估了ERS-1卫星收集的合成孔径雷达（SAR）图像在佛罗里达州西南部湿地植被群落监测中的效用。分析了两幅图像，一幅是在1994年4月旱季结束时收集的，另一幅是在1994年10月雨季结束时收集的。不同测试点的图像强度值范围在旱季ERS-1 SAR图像上变化了6.2倍（7.9 dB），在雨季ERS-1 SAR图像上变化了2.6倍（4.1 dB）。雷达观测结果与理论微波散射模型一致，该模型预测后向散射的变化是植被结构、土壤湿度、表面粗糙度和有无积水的函数。雷达数据和模式均表明，在草本植被为主的湿地，静水的存在导致后向散射减弱。相反，在有木本植物（树木和灌木）的湿地，雷达数据和模式显示，水的存在导致反向散射增加。本研究的结果表明，雷达图像非常适合于探测和监测这些湿地生态系统中土壤湿度、洪水和地上生物量的变化。
This study evaluates the utility of synthetic aperture radar (SAR) imagery collected by the ERS-1 satellite for monitoring wetland vegetation communities in southwestern Florida. Two images were analyzed, one collected at the end of the dry season in April 1994 and one collected at the end of the wet season in October 1994. The range of image intensity values from the different test sites varied by a factor of 6.2 (7.9 dB) on the dry season ERS-I SAR image and by a factor of 2.6 (4.1 dB) for the wet season ERS-1 SAR image. The results from the radar observations were found to be consistent with theoretical micro wave scattering models that predict variations in backscatter as a function of vegetation structure, soil moisture, surface roughness, and the presence or absence of standing water. Both the radar data and models show that, in wetlands dominated by herbaceous vegetation, the presence of standing water results in a decrease in backscatter. Conversely, in wetlands with woody plants (trees and shrubs), the radar data and models show that the presence of water results in an increase in backscatter. The results of this study illustrate that radar imagery is uniquely suited to detect and monitor changes in soil moisture, flooding, and aboveground biomass in these wetland ecosystems.