Airborne and Satellite Imaging for Shallow-Water Habitats

transcript

Survey Methods for Shallow-Water Habitat Mapping in New England Dept. of Interior Holdings and

Estuarine Research Reserves Workshop30 Sep. 2009

Mark Finkbeiner

What is It?Optical energy- UV through NIR

Analog – Aerial

photography

Digital – Aerial multi-

spectral imagery

– Digital camera imagery

Aerial Sensors

• DMC (Z/I Imaging)• UltraCam XP (Vexcel- Microsoft)• ADS-80 (Leica)

• GeoScanner (GeoVantage)• DMSC (Ocean Imaging)• DSS (Applanix)• Others

Satellite Sensors

• GeoEye-1 (GeoEye)• Orbview-2• IKONOS (Space Imaging/GeoEye)• Quickbird (Digital Globe)• WorldView- 2 (Digital Globe)

• SPOT

Advantages• Comprehensive data• Familiar data structure• Amenable to both simple and advanced analysis methods• Captures land-water interface• Broad area coverage possible• Effective in shallow waters• Effective in complex landscapes• Being collected routinely for various other applications

Disadvantages

• Ineffective in deeper water• Limited by water clarity• Environmental considerations

– Atmospheric conditions–Sea state– Turbidity– Sun angle – Tide

Disadvantages

– Atmospheric conditions– Sea state– Turbidity– Sun angle – Tide

Disadvantages

Habitats Amenable to this Technology

• Coastal emergent marsh• Seagrass meadows• Intertidal and shallow-subtidal shellfish beds• Macro algae • Shoreline condition (rocky

shores, beaches, artificial)

• Level of tidal control• Ferry/Staging time• Sensor selection• Flight line complexity• Spatial resolution• Spatial accuracy• Coverage area

Drivers of Acquisition Cost

Aerial• Licensing• Reseller• Rectification order• Vintage• Specific tasking (off-nadir, cloud

restrictions, etc.)• Coverage area

Satellite

• South Carolina Coast $284/sq. mi.

• North Carolina Coast $682/sq. mi.

• Texas Coast $

Costs and ExamplesAerial Image Acquisition Avg. $200 - $500/sq. mi.

Satellite Image Acquisition Avg. $300 - $500/sq. mi.*• Quickbird $72/sq. mi. min. $7,616

• IKONOS $57/sq. mi. min $5,700

• Classification detail• Mapping method• Required accuracy• Coverage area• Minimum Mapping Unit

Drivers of Mapping Cost

Mapping Methods

• Manual digitization High High Low• Spectral clustering Med. Med. Med.• Feature analysis Low Med. High• Image segmentation Low High High

Method Time Effort Logistics

• Manual digitization Low Low• Spectral clustering Med. Med.• Feature analysis High High• Image segmentation High High

Method Precision Repeatability

Costs and Case Studies

Mapping $200 - $500/sq. mi.

• South Carolina Coast $143/sq. mi.

• Long Island South Shore $674/sq. mi.*

• Texas Coast $207/sq. mi.

• Film is going away

• Digital sensors provide additional bands, improved spatial accuracy, greater dynamic range, and a more streamlined process

• Number and availability of airborne digital sensors is increasing

• Satellite resolution is increasing dramatically

• Satellite revisit cycles are decreasing

Emerging Issues and Trends

Airborne and Satellite Imaging for Shallow-Water Habitats

Documents