An Environmental Monitoring System for Lakes and Mashes by Using Aircraft Remote Sensing

利用植物色素叶绿素a的特定反射光谱的波长范围，对可能引起绿藻或赤潮的浮游植物进行遥感技术，通过几个不同波长的反射率的差异来确定叶绿素浓度。认为在较短的时间范围内发生的环境变化以及在较长的时间范围内环境的恶化是一个严重的问题。因此，连续的监测对于了解当前的环境变化和利用积累的数据来评价长期的变化是非常重要的。陆地卫星的数据已经积累了20年，虽然陆地卫星没有能力测量叶绿素的光谱特征，但可以从卫星上获得水的洁净度和颜色的可见光图像数据。飞机(直升机)的观测被认为可以获得基础数据，以补偿大气对卫星数据的影响，因为它可以忽略大气影响。然而，由于测量过程中观测点的变化，机载遥感需要对每一帧进行几何补偿，目前还没有对数据进行快速、准确自动补偿的有效方法。本文介绍了一种对机载数据进行初步的自动数据补偿的过程：1.采用滤波方法，使地面上的实测点与机载探测到的地面点有较好的匹配性。一种叠加多个不同图片数据的方法。

Wave length range of the specific reflection spectrum of plant pigment chlorophyll a is used for the remote sensing technology for plant plankton which may cause the green algae or red tide and the chlorophyll density could be determined with the difference of reflection ratio of several different wave lengths.The problem of environment change which happens in relatively short range in time as well as the aggravation of the environment in a long range of time frame is considered as a serious matter. Therefore, a consecutive monitoring is important for knowing current environment change and utilizing the accumulated data for the appreciation of the change in long term range is desired.The data from LANDSAT have been accumulated for the last 20 years Although LANDSAT does not have the capability to measure the spectrum characteristic from chlorophyll, the visible image data of water cleanliness and color from the satellite are available.The observation from aircraft (helicopter) is considered that it could acquire the fundamental data for compensating the atmosphere effect to the data from satellite because it could ignore the atmosphere effect. However, the remote sensing from aircraft needs geometrical compensation to each frame due to the change of the observatin point during the measurement.Effective method for automatic compensation to the data in fast and accurate manner is not still available, yet.We introduce a preliminary automatic data compensation process to the data from aircraft with introducing ;1. a filtering method to obtain a good matching between the actual points on land and the detected land points from airborne.2. a method to overlay the several different pictorial data.