|
|
Metadata
Each GIS file on this DVD includes an
FGDC
compliant XML metadata file. These
are easily viewed using the metadata tab under ESRI ArcCatalog, or in a web
browser such as Microsoft Internet Explorer. Below are links to generic metadata
files for the data located on this DVD. Additionally, short descriptions
of the types of plots created for each patch reef can be found below.
Links to generic metadata:
- Biological Community and Physical Structure Shapefile -
Contains all the Reef and Fish Community data in standard ESRI shapefile
format. Data parameters are stored as individual parameters within the
shapefile.
- Submerged Elevation DEMs -
DEMs stored as standard single band geotiffs readable
in GIS software packages
such as ESRI ArcGIS.
- Rugosity Maps -
Rugosity (Topographic Complexity) maps stored as standard single band geotiffs
readable in GIS software packages such as ESRI ArcGIS.
- Contours -
Contour lines for the Submerged Elevation DEMs
stored in standard ESRI shapefile
format. These data were used in the main map graphic.
Description of Map Types
- Submerged Elevation (Topographic Digital Elevation Map)
- Lidar Rugosity (Topographic Complexity Map)
Description of Plot Types
- Acanthuridae (Surgeonfish) - Adults
- Acanthuridae (Surgeonfish) - Juveniles
- Chain Rugosity
- Dictyota spp.
- Encrusting Invertebrates
- Gorgonian Volume and Abundance (Gorgonians)
- Haemulidae Adults (Adult Grunts)
- Haemulidae Juveniles (Juvenile Grunts)
- Halimeda tuna
- Live Coral
- Lutjanidae (Snappers)
- Pomacentridae (Damselfishes)
- Scaridae Adults (Adult Parrotfishes)
- Scaridae Juveniles (Juvenile Parrotfishes)
- Serranidae (Groupers)
- Species Richness
- Substratum Coverage
- Total Fish Abundance and Richness
- Submerged Elevation (Topographic Digital Elevation Map)
Elevation data were collected by NASA
using a Cessna 310 aircraft. The NASA
Experimental Advanced Airborne Research Lidar (EAARL) laser scanner collects the data using a green
(532nm) raster scanning laser, while a digital camera acquires a visual record of the flight.
The navigational and raw data, stored on hard drives at the USGS
office in St. Petersburg and
the NASA office at Wallops
Flight Facility, are downloaded into the Airborne Lidar Processing
System (ALPS). Data are then converted from units of time to x,y,z points and the resulting
derived surface data are then converted into gridded raster data. Maps are transverse mercator
projections spatially referenced to the North American Datum of 1983 and vertically referenced
to the North American Vertical Datum of 1988. Elevation measurements have been determined to
be within 1 meter horizontal accuracy and 15 cm vertical accuracy.
- Lidar Rugosity (Topographic Complexity Map)
Rugosity maps are derived from the submerged elevation data. Each data point of the digital
elevation map is analyzed using a 10m by 10m area kernel centered on the point and a synaptic
rugosity value is determined from the ratio: surface area to flat planar map area. Rugosity
values are unit-less.
- Acanthuridae (Surgeonfishes) - Adults
The size of the plotted circle for each station describes the number of adult surgeonfish
observed. The precise values are displayed directly above the plotted circles. Surgeonfish
abundance was measured at each station within 7.5 meter radius imaginary cylinders from
seafloor to water surface using the Bohnsack-Bannerot method.
- Acanthuridae (Surgeonfishes) - Juveniles
The size of the plotted circle for each station describes the number of juvenile surgeonfish
observed. The precise values are displayed directly above the plotted circles. Surgeonfish
abundance was measured at each station within 7.5 meter radius imaginary cylinders from
seafloor to water surface using the Bohnsack-Bannerot method.
- Chain Rugosity
Chain rugosity was determined in situ by divers using the traditional chain-transect
method over a distance of 10 meters. Data are unit-less ratios of contoured distance
versus linear distance. The plot shows the chain rugosity measured at each station on
the patch reef over either the submerged elevation map for the region or the lidar
derived rugosity map.
- Dictyota spp.
The size of the plotted circle for each station represents the percent cover of
Dictyota spp. The precise values are displayed directly above the plotted circles.
Percent cover of Dictyota spp. was estimated in 25 x 25 cm quadrats.
- Encrusting Invertebrates
The size of the plotted circle for each station is determined by the percent cover of
encrusted invertebrates. Encrusted invertebrates is a composite variable representing a
community that negligibly contributes to reef building or sediment production. It includes
Erythropodium caribaeorum, Briareum asbestinum, Palythoa caribaeorum,
Millepora spp., and sponges, but excludes scleractinians. All individual components of
this variable were estimated in 25 x 25 cm quadrats.
- Gorgonian Volume and Abundance
The size of the plotted circle for each station represents the volume of gorgonians
(cm3 per m2). The color of the plotted circle represents the abundance (number of
gorgonians per m2). These data were gathered using 50 x 50 cm quadrats and scaled
up to standard units. These data also exclude the prostrate gorgonians Erythropodium
and Briareum.
- Haemulidae (Grunts) - Adults
The size of the plotted circle for each station describes the number of adult grunts
observed. The precise values are displayed directly above the plotted circles. Grunt
abundance was measured at each station within 7.5 meter radius imaginary cylinders
from seafloor to water surface using the Bohnsack-Bannerot method.
- Haemulidae (Grunts) - Juveniles
The size of the plotted circle for each station describes the number of juvenile grunts
observed. The precise values are displayed directly above the plotted circles. Grunt
abundance was measured at each station within 7.5 meter radius imaginary cylinders
from seafloor to water surface using the Bohnsack-Bannerot method.
- Halimeda tuna
The size of the plotted circle for each station represents the percent cover of Halimeda
tuna. Percent cover of Halimeda tuna was estimated in 25 x 25 cm quadrats.
- Live Coral
The size of the plotted circle for each station is determined by the percent cover of live
corals. Live coral cover was estimated in 25 x 25 cm quadrats.
- Lutjanidae (Snappers)
The size of the plotted circle for each station describes the number of snappers
observed. This plot combines individual measurements for adults and juveniles to
give the total number of snappers observed. The precise values are displayed directly
above the plotted circles. Snapper abundance was measured at each station within 7.5
meter radius imaginary cylinders from seafloor to water surface using the Bohnsack-Bannerot
method.
- Pomacentridae (Damselfishes)
The size of the plotted circle for each station describes the number of damselfish observed.
The precise values are displayed directly above the plotted circles. Damselfish abundance
was measured at each station within 7.5 meter radius imaginary cylinders from seafloor to
water surface using the Bohnsack-Bannerot method.
- Scaridae (Parrotfishes) - Adults
The size of the plotted circle for each station describes the number of adult parrotfish
observed. The precise values are displayed directly above the plotted circles.
Parrotfish abundance was measured at each station within 7.5 meter radius imaginary
cylinders from seafloor to water surface using the Bohnsack-Bannerot method.
- Scaridae (Parrotfishes) - Juveniles
The size of the plotted circle for each station describes the number of juvenile parrotfish
observed. The precise values are displayed directly above the plotted circles.
Parrotfish abundance was measured at each station within 7.5 meter radius imaginary
cylinders from seafloor to water surface using the Bohnsack-Bannerot method.
- Serranidae (Groupers)
The size of the plotted circle for each station describes the number of groupers observed.
The precise values are displayed directly above the plotted circles. Grouper abundance
was measured at each station within 7.5 meter radius imaginary cylinders from seafloor
to water surface using the Bohnsack-Bannerot method.
- Species Richness
The size of the plotted circle for each station describes species richness, defined
as the number of fish species observed. The precise values are displayed directly
above the plotted circles. Species richness was measured at each station within 7.5
meter radius imaginary cylinders from seafloor to water surface using the Bohnsack-Bannerot
method.
- Substratum Coverage
All substratum data are percent cover, estimated in 1 x 1 meter quadrats. The plot
shows pie graphs for each station representing 100 percent cover divided into the
percent individual components observed. Rubble was classified as large when grain
size was between 30 to 40 cm, medium when between 15 to 30 cm, and small when between
1 and 15 cm. Sand was classified here as loose sediment with grain sizes smaller
than 1 cm.
- Total Fish Abundance
This plot shows total fish abundance. The size of the plotted circle for each station
describes the total fish abundance observed. Total fish abundance is the total number
of observed fish. The precise values are displayed directly above the plotted circles.
Fish abundance was measured at each station within 7.5 meter radius imaginary cylinders
from seafloor to water surface using the Bohnsack-Bannerot method.
|