The point cloud data obtained from LiDAR surveys are processed to generate topographic and bathymetric derivative layers. These derivative layers provide continuous surface representations of elevation, point cloud metrics, statistics and other relevant parameters. The quality of the derivative layers to be used in feature extraction is critical in attaining the desired accuracy of results.
Creation of rulesets for the extraction of aquaculture features and mangrove areas is considerably the most tedious part of the entire resource mapping process. The goal is to develop a suitable set of semi-automated procedures using the most appropriate data layers to obtain the maximum classification accuracy possible. Final rulesets to be applied may vary depending on the extent of area to be processed, surface characteristics, and completeness of data layers to be used among other things.
Conduct of field validation is necessary to determine the validity and accuracy of output maps resulting from the application of rulesets and subsequent processing. Field validation techniques for aquatic and coastal resource mapping include collection of ground feature points using GPS and underwater video tows. Only the validated resource maps can be utilized as official references.
CoastMap is one of the five (5) project components of the Detailed Resources Assessment using LiDAR or Phil-LiDAR 2 Program. The Project commenced on July 2014 bearing the official title “Aquatic Resources Extraction using LiDAR Surveys”. It aims to provide an updated and detailed inventory of high-value coastal resources in the Philippines. It is specifically concerned with the development of algorithms and workflows for extracting and characterizing coastal resources using LiDAR and other remotely sensed data, and field measurements; production of high resolution and high accuracy maps of coastal resources; and vulnerability assessment of different coastal resources. Among the expected outputs of the Project are the algorithms and workflows for data processing, output maps, geodatabases, and spectral library of various coastal resources such as mangroves, corals and seagrass.
CoastMap is driven by the collaborative efforts between fourteen (14) participating state universities and colleges and higher educational institutions (SUCs & HEIs), and the support of various government agencies and institutions. The University of the Philippines Training Center for Applied Geodesy and Photogrammetry (UP TCAGP) spearheads the development of methodologies and workflow, enhances the capability of research teams through training and mentoring sessions, evaluates the Project outputs, and builds a web-based platform for the compilation and dissemination of validated output maps together with other technical information. The SUCs & HEIs on the other hand are responsible for the processing of datasets, field validation, and map generation in their respective target areas.
In the span of three years, CoastMap is able to develop a comprehensive methodology for the extraction of aquatic and coastal resources using LiDAR and other geographic datasets. This encompasses all stages of resource mapping, from conduct of case studies and actual data processing to field validation and output maps generation. The processes involved have undergone several iterations to ensure the quality of outputs. Ultimately, the Project is able to produce hundreds of resource maps which are readily accessible through this web portal. These resource maps were initially turned over to the local government units and government agencies concerned.
The Project officially closes at the end of December 2017. With the mechanisms in place, it is the hope of the CoastMap research team that the outputs be fully accessed and utilized for the advancement of aquatic and coastal resources in the country. It is only then can the Project be considered a complete success.