Sea Grant Project R/ET-5
"Development of High Resolution Satellite and GIS Techniques
for Monitoring and
Assessment of Coastal Ecosystems"
| Principal Investigator |
Klemas, Victor V. |
| Co-principal Investigator |
Field, Richard |
| Associate Investigator 1 |
Hall, William |
| Associate Investigator 2 |
Yan, Xiao-Hai |
OBJECTIVES:
(1) To develop techniques for monitoring landscape level
environmental indicators using new high-resolution satellite imagery for
providing quantitative estimates of wetland and estuarine habitat conditions
and trends. (2) To determine what ancillary data and image analysis techniques
are required to reliably detect critical wetland health indicators, such
as biomass change, fragmentation, riparian buffers, invasive species, etc.
if medium resolution satellite imagery (Landsat TM) is combined with high
resolution imagery (IKONOS) (3) To work with the Marine Advisory Service
to prepare websites for high school students, teachers and the general
public illustrating the history of Delaware's tidal wetlands and how the
new remote sensing techniques help coastal managers to restore, enhance
and protect them.
METHODOLOGY:
We will analyze high-resolution imagery of several well-documented
sites, for which we have much ancillary data (e.g. Blackbird Creek and
St. Jones River National Estuarine Research Reserve Sites, Milford Neck
Wildlife area). About half the required satellite/aircraft imagery is already
on hand; the rest will be obtained from NRL and NASA. First we will analyze
the spatial variability of our test sites to determine if the spatial resolution
of the imagery is suitable for detecting the relevant coastal features.
Next we will perform multispectral analysis using the high-resolution images.
In addition to wetland loss, changes in critical environmental indicators,
such as biomass, will be studied. We will evaluate the accuracy of the
multispectral analysis results individually and when combined with ancillary
data in a GIS. Ancillary data layers will be used for interpreting the
multispectral analysis maps and comparing their accuracy to existing maps
and medium resolution satellite results.
During the first year we have performed spectral and
spatial analyses of existing satellite/aircraft imagery to determine the
spectral characteristics of the wetland classes and features at our test
site. We have acquired leaf-on high resolution satellite/aircraft data
from overflights and contemporaneous field observations on the ground.
During the second year, these first year multispectral observations will
be analyzed to map wetland health attributes. A preliminary analysis of
map accuracy will be performed. The second year of leaf-on high resolution
satellite/aircraft data will be acquired in association with intensive
ground observations. During the third year we will perform the final accuracy
assessment and will have wetland managers and researchers evaluate the
results. An educational computer module in software such as ArcExplorer
and/or PowerPoint, of the wetland remote sensing techniques will be completed
and tested for use in high schools and regional institutions. Reports and
papers will be prepared each year.
RATIONALE:
Many coastal features are small and have narrow, elongated
shapes, such as mud flats, riparian/shoreline buffers, monospecific wetland
stands or wetlands existing along edges of bays and rivers. Therefore they
are difficult to detect with 20-30 meter resolution satellite imagery.
Furthermore, wetland and water pollutants have complicated spectral reflectance
signatures and are difficult to identify with only the available 3 to 6
spectral bands. Recently new satellites are being launched which are providing
imagery with spatial resolutions of 1 to 4 meters (e.g. IKONOS). There
is an urgent need to develop mapping techniques, which use the spectral
and spatial content of these high-resolution images, to enable researchers
and managers to monitor wetland habitat cost-effectively. There is also
a need to get students educated about the history of Delaware?s wetlands
and these new technologies and to demonstrate to the public how these techniques
are helping us to restore, enhance and protect coastal ecosystems.
PROJECT RESULTS:
In our preliminary research we have shown that high-resolution
satellite or aircraft imagery can be used to classify wetlands and detect
habitat features (e.g. fragmentation, riparian buffers, mudflats, invasive
species, biomass) important to wildlife, including migratory birds. Specifically,
at 1 meter to 4 meter resolutions we have been able to differentiate wetland
types by their spatial, as well as spectral characteristics. It seems that
combining spatial and spectral analyses of high-resolution satellite imagery
will produce an effective approach for monitoring wetland type, extent
and health. We found that the Modified Soil Adjusted Vegetation Index give
best results for wetland biomass change determination. Our improved method
for mapping wetland biomass changes requires fewer field samples and corrects
for seasonal, tidal and soil reflectance variations without the need for
local correction factors.
ACCOMPLISHMENTS:
High resolution multispectral (4m) and panchromatic
(1m) IKONOS satellite imagery has been received from NASA for all three
test sites. The imagery has been processed and multispectral analysis initiated.
The test sites have been segmented between tidal and non-tidal areas. The
non-tidal areas are further segregated into upland, forested wetland, and
emergent wetland areas with the aid of such ancillary data as the NWI and
Delaware?s SWAMP data sets. Historical thematic mapper scenes from 1984
to 1997 are being subset for analysis of the study areas using the Modified
Soil Adjusted Vegetation Index to identify areas of wetland change. In
addition, a historical examination of the tidal wetlands of the Delaware
River and Estuary, which shows that all of the tidal wetlands have been
impacted by human use, has been completed and is being prepared for presentation
to the public on the World Wide Web.
BENEFITS:
The new remote sensing and GIS techniques being developed
provide reliable information on wetland habitat status and trends to local
and regional agencies and researchers. The high-resolution imagery enables
us to study wetlands fragmentation, riparian buffers, impervious areas,
invasive species, plant biomass and other landscape-level environmental
indicators which heretofore were difficult to detect from satellite altitudes.
The quality of the high-resolution wetland and related data products will
be evaluated by coastal planners, managers and researchers to see how well
they can be integrated with other data in a GIS to more effectively monitor
coastal ecosystems. If the results of this evaluation are positive the
new techniques will form the basis for designing a system for long-term
monitoring of Delaware Bay habitats.
The educational computer presentation will be such that
its format could be adopted by teachers of marine sciences, earth sciences
and physical sciences. SG Marine Advisory Service personnel will help to
implement this outreach component.
MARINE ADVISORY SERVICE INTERACTION:
The Marine Advisory Service (MAS) will guide us in the
application of our results to coastal resource management. The research
project will be carried out in conjunction with the Delaware Chapter of
The Nature Conservancy, Delaware Wildlands, Inc., the Delaware Department
of Natural Resources and environmental Control (see letter of support)
and the Delaware National Estuarine Research Reserve Program. All four
groups will make field sites available to our team and help in the field
data collection.
Other regional projects which have been collaborating
with us and will benefit from this research include:
1) The FWS GAP Analysis Project (FWS and DE, MD, NJ)
2) The Delaware Coastal Management Program (NOAA and
State of Delaware)
3) The Delaware Estuary Program (EPA and DE, NJ, PA)
4) The Delaware Inland Bays Estuary Program (EPA and
State of Delaware)
The Marine Advisory Service (MAS) will also help us develop
an educational computer presentation module for high school students, teachers
and the public illustrating how the new remote sensing techniques will
help protect, enhance and restore coastal ecosystems. We will explore commercial
software packages to determine the most appropriate media for the presentation.
Options include using an off-line web browser, Microsoft's PowerPoint,
or Adobe Acrobat. The presentation material will be tested by the MAS at
local schools and institutions. A final presentation version will be made
available on the Internet.
back to
the Sea Grant Research
Last modified: October 17, 2001
Xuebin Zhang --- xbzhang@newark.cms.udel.edu