东平湖水体透明度的遥感反演研究

Remote sensing inversion of water transparency in Dongping Lake

针对传统水体透明度测量方法不仅耗时费力,而且在时间和空间的监测中也会受到很大的限制,只能了解研究区域内点状剖面的透明度状况,但是遥感技术的发展为解决传统采样方法的局限性问题提供了可能。该文在分析内陆湖泊水体光学特征的基础上,利用三期Landsat8 OLI影像数据及准同期的地面实测数据,寻找与东平湖水体透明度敏感的波段,对东平湖丰、平、枯水期水体透明度的进行遥感反演研究。结果表明,OLI影像B3、B4波段的反射率与实测的透明度数据之间具有良好的相关关系,并以此为基础建立了该区域水体透明度遥感反演模型。结果表明:模拟值与实测值的总体相对误差为19.77%,均方根误差为19.35cm,模型精度在可以接受的范围之内;由于受围网养殖、叶绿素a含量等因素的影响,东平湖透明度总体呈现出南低北高的分布趋势。据此绘制了东平湖丰、平、枯水期水体透明度分布图。

Secchi disk depth（SDD）is an important component of water routine,which affects the optical properties and primary productivity of water body.The traditional measuring method is not only timeconsuming but also restricted terms of temporal and regional coverage,while remote sensing inversion can deal with these limitations.In this study,remote sensing inversion in Dongping Lake was carried out by using three Landsat8 OLI image data and quasi synchronous ground measured data.The results illustrate the band ratio model of Band3＋Band4 of OLI could be used to estimate secchi depth in this region,with RE of 19.77% and RMSE of 19.35 cm,respectively.In addition,SDD was deeper in north waters than in south waters.Based on these,the distribution of water transparency in Dongping lake during the rainy,flat and dry seasons was plotted,and its distribution trend and cause were analyzed.