Photogrammetry

This research develops a new pipeline for large-scale point cloud registration by integrating chunked-based data processing within feature-based deep learning models to align aerial LiDAR and UAV photogrammetric data. By processing data in manageable chunks, this approach optimizes memory usage while retaining the spatial continuity essential for precise alignment across expansive datasets. Three models—DeepGMR, FMR, and PointNetLK—were evaluated within this framework, demonstrating the pipeline’s robustness in handling datasets with up to 49.73 million points. The models achieved average epoch times of 35 seconds for DeepGMR, 112 seconds for FMR, and 333 seconds for PointNetLK. Accuracy in alignment was also reliable, with rotation errors averaging 2.955, 1.966, and 1.918 degrees, and translation errors at 0.174, 0.191, and 0.175 meters, respectively. This scalable, high-performance pipeline offers a practical solution for spatial data processing, making it suitable for applications that require precise alignment in large, cross-source datasets, such as mapping, urban planning, and environmental analysis.

Quantifying and understanding coral community dynamics, including recruitment, is critical for developing effective ecosystem management strategies, particularly in areas that have experienced significant coral losses such as Southeast Florida’s Kristin Jacobs Coral Reef Ecosystem Conservation Area. While several federal, state, and regional efforts effectively track annual changes in juvenile and adult coral colonies, few coral reef monitoring programs are designed to track new coral recruitment. This study’s aims were to assess potential differences in community composition of adult and recruit stony corals in southeast Florida using phototransects, and to test the efficacy of eDNA approaches for monitoring coral recruitment. Replicate phototransects demonstrated significant differences in recruit density and community composition across sites. This photogrammetry approach was more applicable than eDNA and indicates that site specific management and restoration strategies in a regional context may be warranted for the study area.

Since 2014 stony coral tissue loss disease (SCTLD) has contributed substantially to declines of reef-building corals in Florida. Monthly surveys were conducted throughout the northern Florida reef tract to monitor the spread and impacts of SCTLD on a larger spatial scale. SCTLD disease prevalence was lower in Palm Beach County than in Broward or Martin County, but there were no significant changes in prevalence over time. To assess colony level impacts of the disease, this study optimized a 3D photogrammetry technique for fate-tracking infected Montastraea cavernosa coral colonies with a low-cost, rapid protocol that measured tissue area over three time points. Total colony area and healthy tissue area decreased significantly over time, while disease area did not significantly vary. Traditional coral surveys combined with the 3D photogrammetry method provide greater insights into the spatial/temporal dynamics and impacts of this disease on individual corals and reef populations than surveys alone.