Guild, Liane: NASA ARC (Project Lead)
Project Funding:
2007 - 2010
NRA: 2006 NASA: Interdisciplinary Research in Earth Science
Funded by NASA
Abstract:
In response to the most devastating regional-scale coral bleaching events on record in the US Caribbean, scientists from NASA Ames and the University of Puerto Rico teamed in December 2005 to rapidly assess the extent of coral bleaching, mortality, recovery, and ecological impact in Puerto Rico (PR). The bleaching event resulted from sustained increased seawater temperatures between September-October 2005. This assessment was part of a larger multi-agency effort in a partnership with NOAA and the US Coral Reef Task Force to evaluate the effects of this Caribbean-wide bleaching event. The PR assessment included both the acquisition of hyperspectral imagery using NASA's Airborne Visible Infrared Imaging Spectrometer (AVIRIS) onboard the NASA Twin Otter as well as the collection of field data by NASA Ames and University of Puerto Rico coral reef researchers.
The goal of the proposed research is to study how coral reefs respond following a bleaching event of this magnitude by using hyperspectral and field data to assess coral recovery, mortality, and possible overgrowth of macroalgae. To investigate the response, we will test practical applications in remote sensing for describing and monitoring biological and physical properties of reefs following bleaching, concentrating on aspects that enhance both understanding and prediction of reef biodiversity and degradation.
We propose integrating satellite imagery (multiple dates of multispectral Ikonos and hyperspectral Hyperion) and airborne imagery (hyperspectral AVIRIS from 2004 and 2005) over PR with a wealth of long-term biological field data in PR collected prior to and following the bleaching event to contribute to research on the ecological structure and benthic habitat biodiversity of coral reefs. We will compare the AVIRIS imagery, which has high spatial and spectral resolution information, with Ikonos and Hyperion satellite data and integrate the image processing results with in situ measurements from diving surveys and autonomous underwater vehicle (AUV) photo transects. Biological information collected for the study area includes bio-optical properties of reef bottom types and their variations due to disturbance (i.e., bleaching, disease), percent cover of benthic types, coral patchiness, distance between patch reefs, rugosity, and species abundance and distribution. Spatial patterns and connectivity of patch reefs and associations with other benthic habitats will be revealed through analyses of remote sensing and in situ data for characterizing ecological structure. Plot and AUV transect measurements of biodiversity will be scaled up to the resolution of the remote sensing data with particular attention to error propagation in scaling. A critical contribution of this work is to map the distribution of the declining Acropora species (elkhorn and staghorn coral), which have been proposed for listing under the US Endangered Species Act and are an important dominant reef builder in the Caribbean and Florida. Further, the presence of macroalgae overgrowth on coral is of special interest for monitoring ecological phase shifts. The proposed team is well positioned to succeed in this research, having already obtained a unique data set together with long-term research data acquired in the area and possess extensive experience in the analysis of remote sensing data. This research supports the US Climate Change Science Program and the US Ocean Action Plan objectives. This work also has direct significance to research subelement 3 of the Interdisciplinary Research Themes, "Biodiversity and Disturbance", by improving our understanding of the threats to reef biodiversity posed by increased seawater temperatures, the resulting coral reef bleaching, and the response of reef communities to bleaching and disease.
2011 NASA Carbon Cycle & Ecosystems Joint Science Workshop Poster(s)
- Imaging Spectroscopy, Spectral Analysis, and Radiative Transfer Modeling in Support of Coral Reef Ecosystem Biodiversity Research for Coral Patch Reefs in Puerto Rico
-- (Liane Guild, Roy Armstrong, Bradley Lobitz, James Goodman, Fernando Gilbes, Randall Berthold, Juan Torres, Yasmin Detres, Carmen Zayas, Jeremy Kerr, Orian Tzadik)
[abstract]
[poster]
More details may be found in the following project profile(s):
