Utilizing Underwater Three-Dimensional Modeling to Enhance Ecological and Biological Studies of Coral Reefs

Abstract

ABSTRACT:The structural complexity of coral reefs profoundly affects the biodiversity, productivity, and overall functionality of reef ecosystems. Conventional survey techniques utilize 2-dimensional metrics that are inadequate for accurately capturing and quantifying the intricate structural complexity of scleractinian corals. A 3-dimensional (3D) approach improves the capacity to accurately measure architectural complexity, topography, rugosity, volume, and other structural characteristics that play a significant role in habitat facilitation and ecosystem processes. This study utilized Structure-from-Motion (SfM) photogrammetry techniques to create 3D mesh models for several Hawaiian corals that represent distinct morphological phenotypes. The orthophotos and digital elevation models generated from the SfM process were imported into geospatial analysis software in order to quantify several metrics pertaining to 3D complexity that are known to affect ecosystem biodiversity and productivity. The 3D structural properties of the reconstructed coral colonies were statistically analyzed to determine if the each species represents a unique morpho-functional group. The SfM reconstruction techniques described in this paper can be utilized for an array of research purposes to improve our understanding of how changes in coral composition affect habitat structure and ecological processes in coral reef ecosystems.

Underwater photogrammetry in Antarctica: long-term observations in benthic ecosystems and legacy data rescue

“…Seascape, Teixidò et al 2011, and photoQuad, Trygonis and Sini, 2012). Underwater photogrammetry has then been exploited in hostile environments or remote areas (Westoby et al, 2012), in applications where accuracy, high level of details and minimum environmental impact are fundamental, such as, for example, in coral reef (Burns et al, 2015a;2015b;Annelli et al, 2017) and seafloor mapping and monitoring (Friedman et al, 2012;Guo et al, 2016).…”

Photogrammetric Surveys and Geometric Processes to Analyse and Monitor Red Coral Colonies

“…See, for example, Refs. [27][28][29] or the study of structural complexity of underwater seafloor [30][31][32]. GIS software is also coupled with photogrammetry in [33] for a deep coral survey.…”

Low-Cost 3d Laser Scanning in Air Orwater Using Self-Calibrating Structured Light

“…For example, the development of coral reefs is an important indicator of the wellbeing of the marine ecosystem. Having accurate measurements of the structural complexity of corals gives scientiests an indicator of the genetic diversity and spreading of diseases (Burns et al, 2015). Simple, low-cost 3D underwater sensors can have a significant impact on our ability to study the oceans.…”

“…Today, low-cost action cameras provide easy access to suitable technology for acquiring underwater images and videos. Subsequently, photogrammetry has become a popular technique for creating 3D models of submerged environments and has been applied to diverse scientific and industrial applications, such as marine ecosystem monitoring (Burns et al, 2015), non-destructive documentation of archaeological sites (Drap et al, 2007), or surveys of ship accidents (Menna et al, 2013).…”