11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 17: Emerging Techniques in Remote Sensing and Geospatial Analysis
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Different Pigments Composition Can Influence The Remote Sensing Reflectance Of
Caribbean Shallow-Water Coral Species
Juan TORRES* 1 , Roy ARMSTRONG 2
1 Biology Department, University of Puerto Rico at Rio Piedras, San Juan, Puerto Rico,
2 Department of Marine Sciences, University of Puerto Rico at Mayaguez, Lajas, Puerto
Rico
The pigment composition of the Caribbean shallow-water coral species Acropora
cervicornis and Porites porites was determined using HPLC analysis. Nineteen different
pigments were identified including chlorophylls and carotenes. Of these, ten were
common in both species; six appeared only in A. cervicornis, and four appeared only in
P. porites. It is hypothesized this is the result of different zooxanthellae clades that
inhabit these coral species. The results showed how the differences in pigments
composition influence the remote sensing reflectance (Rrs) signal of both species. While
the Rrs appeared to be very similar in both species, derivative analysis showed marked
differences resulting from the absorption of the pigments, especially in the blue region of
the spectrum (400-500 nm). The combination of both techniques can be used to further
create a spectral library to identify shallow-water coral species in hyperspectral images.
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A New Method for Monitoring Along-Track Topographic Complexity
Monica PALASEANU-LOVEJOY* 1 , John BROCK 2 , Kristi FOSTER 3 , Amar
NAYEGANDHI 4 , David NAGLE 1
1 FISC, USGS / Jacobs, St. Petersburg, FL, 2 FISC, USGS, St. Petersburg, FL, 3 NOVA
University, Dania Beach, FL, 4 FISC, USGS / ETI, St. Petersburg, FL
Topographic variability is an important characteristic of habitat complexity that
influences the abundance and distribution of many reef organisms. One measure of
topographic variability is rugosity, defined as the ratio of the real distance between two
points and their projected distance on a horizontal plane. Traditionally, rugosity is
measured in the field using the chain transect method. In this study, we used Marimatech
sounder data collected at a nominal horizontal spacing of 2 to 10 cm to calculate alongtrack
rugosity. Concomitant, geo-located images were acquired via the Along-Track
Reef-Imaging System (ATRIS) placed opposite the Marimatech sounder transducer on
the survey vessel. The ATRIS Data Analysis and Processing Tool (ADAPT) allows
interactive geographic browsing, scalling, and classification of each image. We identified
six different habitats: seagrass, sand, hard ground / algae / turf, dense coral reef, sparse
coral reef, and dead coral. Each point for which rugosity was calculated was associated
with the closest classified image. The Welch t-test confirmed that the true divergence in
population means is different than zero. The f-test endorsed that the true population
variances are statistically dissimilar for each habitat class, although hardground, dense
coral and sparse coral variances were not essentially different than dead coral variances
in the Fligner - Killen test of homogeneity of variances. The mean habitat rugosity values
indicated that seagrass had the least complex topography, with complexity increasing
from dead corals to sand, hard-ground / algae/ turf, and sparse mixed reef. Probably sand
had a higher rugosity mean value due to dense ripples. The dense mixed reef had the
highest habitat complexity among the six identified classes.
17.567
Assessing Patterns Of Patch Reef Distribution in The Lower Florida Keys, Usa, Using
Ikonos Satellite Imagery
Melanie PETERS* 1 , David PALANDRO 1 , Pamela HALLOCK-MULLER 2 , Eugene SHINN 2
1 Florida Fish and Wildlife Research Institute, St. Petersburg, FL, 2 College of Marine Science,
University of South Florida, St. Petersburg, FL
Declines in overall coral cover throughout the Florida Keys are well-documented. However,
coral cover on patch reefs is variable, with high coral cover remaining on some patch reefs. As
live coral cover on the offshore bank reefs continues to decline, remaining shallow-water coral
assemblages may ultimately be concentrated in the large number of thriving patch reefs.
Previous efforts to determine the number of patch reefs in the Lower Keys utilized aerial survey
methods. A major study published in 1977 identified 420 reef structures from Big Pine to the
Marquesas Keys. Our study used IKONOS satellite imagery to find and map the size and
distribution of patch reefs; we identified approximately 2500 patch reefs in the same region.
Initial observations indicate that patch-reef distribution is non-random and appears to correlate
with geologic features. Patch reefs occur in three distinct cross-shelf zones, each with increasing
distance from shore. There is also clear segregation between patch-reef morphologies, with
different types rarely sharing a given zone. It is crucial to understand not only the spatial
distribution of patch reefs, but also why they originated and persist in specific geographic
locations. Previous studies cited Florida Bay water and mobile calcareous sands as primary
determinants of patch-reef growth, with patch-reef development focused on trough edges
bordering Hawk Channel. In addition to the patch reefs along Hawk Channel, we found a third
zone of thriving patch reefs near shore (0.3% - 52% coral cover, mean 17%). Key to our longterm
analysis will be to determine what affects, if any, environmental and geological influences
have on patch morphology and how this is manifested in the spatial arrangement of patch reefs.
17.568
Sea Surface Temperature Trend in The Coral Triangle in Two Decades
Eileen PEÑAFLOR* 1 , William SKIRVING 2 , Scott HERON 2 , Laura DAVID 1
1 Marine Science Institute, University of the Philippines, Quezon, Philippines, 2 Coral Reef
Watch, National Oceanographic and Atmospheric Administration, Townsville, Australia
Increasing ocean temperature has become one of the major concerns in the recent decades.
Pronounced increase in sea surface temperature (SST), for example, had caused massive coral
bleaching in many regions particularly during the 1997-98 ENSO event. This study focuses on
the Coral Triangle and utilizes the National Oceanographic and Atmospheric Administration-
Coral Reef Watch (NOAA-CRW) SST from 1985 to 2006 to investigate the SST condition in
the area during this period. Another NOAA-CRW product, Hotspot, is also used as a supporting
data to locate areas with anomalously warm surface waters. Results show that this region’s SST
has been increasing at the rate of 0.2 oC/decade on average from 1985-2006. Warming within
this region, however, is not uniform in space or time. Overall, sites located on the north and east
of the triangle show a faster warming trend. Also, although an overall increase has been seen
through the years, the eruption of Mount Pinatubo in the Philippines in 1991 had contributed to
a significant lowering down of SST in the region for at least 2 years after the eruption.
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