漂浮大型藻运移高分辨率遥感观测:以黄海浒苔绿潮为例  

High-resolution remote sensing of the transportation of floating macroalgae: Case studies with the Ulva prolifera green tide

作　　者：刘海龙 邢前国[1,2,3] 丁静 刘建强[4] 郑向阳[1,2] 吴玲娟[5] 李琳 陆应诚[6] LIU Hailong;XING Qianguo;DING Jing;LIU Jianqiang;ZHENG Xiangyang;WU Lingjuan;LI Lin;LU Yingcheng(CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation,Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences,Yantai 264003,China;Shandong Key Laboratory of Coastal Environmental Processes,Yantai 264003,China;University of Chinese Academy of Sciences,Beijing 100049,China;National Satellite Ocean Application Service,Ministry of Natural Resources Beijing 100081,China;North China Sea Marine Forecasting Center,State Oceanic Administrator,Qingdao 264061,China;International Institute for Earth System Science,Nanjing University,Nanjing 210023,China)

机构地区：[1]中国科学院烟台海岸带研究所中国科学院海岸带环境过程与生态修复重点实验室,烟台264003 [2]山东省海岸带环境过程重点实验室,烟台264003 [3]中国科学院大学,北京100049 [4]自然资源部国家卫星海洋应用中心,北京100081 [5]国家海洋局北海预报中心,青岛264061 [6]南京大学国际地球系统科学研究所,南京210023

出　　处：《遥感学报》2023年第1期187-196,共10页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家自然科学基金(编号:42076188,41676171,4181101363);中国科学院战略性先导科技专项(A类)(编号:XDA19060203,XDA19060501);中国科学院仪器研制(编号:YJKYYQ20170048)。

摘　　要：遥感是海表漂浮大型藻监测的重要手段。本研究基于无人机、高分辨率卫星(Sentinel-2 MSI、GF-6 WVF、HY-1C/D CZI)获取的3组像对,对不同尺度的黄海漂浮大型藻浒苔斑块及其精细化运移过程进行了观测。其中,基于HY-1C/D双星组网实现了2.45 h内50 m分辨率级别的斑块点对点跟踪,在观测时段,风与海洋潮流的方向较为一致,二者效应叠加,使得浒苔的运移速度相对较高,平均运移速度为0.380 m/s。在10 m级分辨率的MSI、WVF影像上,浒苔斑块的水团锋面或辐聚区在不同观测角下,会导致更多或更少的入瞳太阳耀光呈现出亮、暗的区域由太阳耀光异常表征的这类辐聚区在近30 min内持续存在,且发生了明显迁移,其平均速度约为0.2 m/s。基于厘米级超高分辨率无人机图像可实现秒级至分钟级别的漂浮大型藻运移观测,平均速度为0.066 m/s,小斑块浒苔受风的影响,沿风向呈链条状分布特征,两者夹角小于15°。结果显示,浒苔斑块多呈条状,其延伸方向在不同尺度上表现出与风向的一致性,显示出风对浒苔斑块运移的影响;基于太阳海表耀光表征的海流辐聚区及浒苔斑块的空间位置变化,体现了海流动力过程对浒苔运移的影响。本研究显示,通过高时空分辨率的光学像对可对海表漂浮大型藻的运移精准观测,可望用于其运移物理动力机制的研究。Remote sensing is an important tool for monitoring floating macroalgae over the sea surface. In this study, three pairs of images obtained by a drone and high-resolution satellites(Sentinel-2 MSI, GF-6 WVF, HY-1C/D CZI) were selected to monitor the movements of floating green tide macroalgae(Ulva prolifera) in the Yellow Sea with multiple spatial scales. Based on the HY-1C/D double-star network,the point-to-point tracking of patches with a resolution level of 50 m within 2.45 hours is realized. During the observation period, the direction of wind and ocean current is relatively consistent and the superposition of the two effects makes the movement speed of macroalgae relatively high, with an average speed of 0.380 m/s. On the 10 m resolution MSI and WVF images, the water mass front or convergence area of macroalgae patches at different observation angles will lead to more or less bright and dark areas of the incoming pupil solar flare. This kind of convergence area characterized by solar flare anomaly has continued to exist 30 minutes, and has undergone significant movement, with an average velocity of about 0.2 m/s. Based on centimeter-level ultra-high-resolution UAV images, the movement observation of floating macroalgae can be realized from seconds to minutes, with an average speed of 0.066 m/s. Influenced by wind, small patches of macroalgae are distributed in a chain shape along the wind direction, and the angle between them is less than 15°. The results suggested that the orientations of macroalgae patches were consistent with wind directions, indicating the influence of wind on the movement of floating macroalgae. The convergent zones and the position changes of macroalgae patches identified from sun glitter reflected the influence of ocean hydrodynamics on the movement of macroalgae patches. This study demonstrates that high-resolution optical images can be applied for accurately monitoring the movement of floating macroalgae, as well as the investigation of the corresponding physical dynamic mechanisms.

关 键 词：HY-1C/D CZI GF-6 Sentinel-2 无人机 运移 漂浮大型藻 绿潮 浒苔 黄海 

分 类 号：P2[天文地球—测绘科学与技术]