淤泥质潮滩高程的遥感监测机理与方法研究

Elevation of muddy intertidal flat is a prerequisite and indispensible data resource for topographic evolution analysis and coastal hydrodynamic numerical simulation. However, it is not easy for traditional ways such as shipborne depthometer and RTK-GPS to measure topography of intertidal flats because of the difficult access and limitation of exposure time. As a result, we propose a new way, called remote sensing moisture method, to retrieve intertidal elevation. When the tide ebbs, the intertidal surface exposes gradually from the land to the sea, thus forming a phenomenon of “low moisture in high-lying areas and high moisture in low-lying areas.” Accordingly we put forward to a hypothesis that moisture has a negative correlation with elevation of exposed intertidal flats. If the hypothesis is true, remote sensing can be used to obtain intertidal elevation indirectly based on a successful moisture estimation on exposed intertidal surface. For this purpose, this project intends to (1) achieve moisture retrieval by remote sensing image through analyzing the relationship between reflectance and moisture; (2) prove the authenticity of original assumption through analyzing the relationship between the moisture and the elevation; (3) based on the relationship between reflectance and moisture and the relationship between moisture and elevation, moisture as the intermediate variable was used to build the elevation retrieval model. Remote sensing moisture method is a new way to monitor muddy intertidal elevation and its potential contribution is able to enrich the remote sensing methodology system of coastal information extraction.

淤泥质潮滩高程是冲淤演变分析、海岸水动力数值模拟等研究必需的基础资料。由于淤泥质潮滩滩面泥泞、潮沟纵横分布，传统的船舶与陆地测绘方法都很难测量潮滩高程。本申请提出利用“遥感含水量法”反演潮滩高程的思路。退潮后潮滩表面由陆向海逐渐出露，形成了“地势高的区域含水量低，地势低的区域含水量高”的现象。据此提出研究假设：“出露滩面含水量与高程呈负相关关系”。若假设成立，就可以利用遥感影像反演滩面含水量，从而间接获得潮滩高程。本项目拟通过：（1）研究光谱与含水量的关系，实现滩面含水量的遥感反演；（2）分析含水量与高程的关系，论证研究假设；（3）若假设成立，则以含水量为中间变量，建立光谱与高程的关系模型，实现潮滩高程的遥感反演。“遥感含水量法”反演淤泥质潮滩高程的研究思路具有创新性，预期成果可充实海岸带遥感信息提取方法体系，能为研究潮滩动态演变规律提供基础地理数据和技术支撑。

淤泥质潮滩高程是冲淤演变分析、海岸水动力数值模拟等研究必需的基础资料。由于淤泥质潮滩滩面泥泞、潮沟纵横分布，传统的船舶与陆地测绘方法都很难测量潮滩高程。本申请提出利用“遥感含水量法”反演潮滩高程的思路。退潮后潮滩表面由陆向海逐渐出露，形成了“地势高的区域含水量低，地势低的区域含水量高”的现象。本项目通过研究光谱与含水量的关系，实现滩面含水量的遥感反演；分析含水量与高程的关系，证实潮滩含水量和高程存在负相关关系，进一步以含水量为中间变量，建立光谱与高程的关系模型，实现了潮滩高程的遥感反演。“遥感含水量法”反演淤泥质潮滩高程的研究思路具有创新性，本研究成果可充实海岸带遥感信息提取方法体系，能为研究潮滩动态演变规律提供基础地理数据和技术支撑。