盐城候鸟栖息地岸线变化特征及其对候鸟栖息地影响

Shoreline Changes in the Migratory Bird Habitat in Yancheng and Their Impact on the Habitat of Migratory Birds

近年来,黄(渤)海候鸟栖息地侵蚀严重,岸线分布变化迅速,这对海岸带生态与经济带来了挑战。本文基于2013—2022年8期Sentinel-2及Landsat 8多源卫星遥感影像,利用人机交互方法解译提取候鸟栖息地岸线,通过ArcGIS平台数字岸线分析系统(Digital Shoreline Analysis System,DSAS)将岸线数字化,计算得到年际与年内岸线变迁时空分布,并探讨了蚀淤变化的成因及影响。结果表明:2014—2022年候鸟栖息地侵蚀特征由原先的侵蚀范围广但侵蚀速率小,转变为侵蚀范围集中且侵蚀速率大幅增加,侵蚀危害严重加剧。侵蚀集中在春季及夏季。研究区域岸线变迁受到多种因素的综合影响,包括泥沙来源、近岸海流、沿岸地物类型、人工建筑及风暴潮等。明确近年候鸟栖息地重点侵蚀岸段动态变化并分析其成因,对当地海岸带的生态经济保护及管理具有重要意义。

In recent years the migratory bird habitat in the Yellow(Bohai)Sea has been eroded so seriously that the shoreline distribution in the habitat changes rapidly.This poses ecological and economic challenges to the coastal zones.Based on 8 phases of Sentinel-2 and Landsat 8 satellite remote sensing images obtained from 2013 to 2022,the shorelines in the migratory bird habitat are extracted by using the human-computer interaction methods and digitized through the Digital Shoreline Analysis System(DSAS)of the ArcGIS platform.And then,the spatial and temporal distributions of interannual and intraannual shoreline changes are calculated out and the causes and influences of erosion-silting change are discussed.The results indicate that from 2014 to 2022,the erosion of the migratory bird habitat changed from original wide range but small erosion rate to a concentrated range but large increase in erosion rate,indicating a seriously aggravaed erosion harm,and the erosion occurred mainly in spring and summer.The shoreline changes in the study area are comprehensively affected by multiple factors such as sediment sources,nearshore currents,coastal feature types,artificial structures and storm surges.It is of great significance to the ecological and economic protection and management of local coastal zone to clarify the dynamic changes of key eroded coast segments in the migratory bird habitat in recent years and analyze their causes.