Using Global Positioning Systems in Submerged Aquatic Vegetation Mapping

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Using Global Positioning Systems in Submerged
Aquatic Vegetation Mapping

• Shakira D. Turner

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• A leading innovator of Global Positioning System
  (GPS) technology.
• Augments GPS with other positioning technologies
  as well as wireless communications and software.
• Trimble's applications include surveying,
  automobile navigation, machine guidance, asset
  tracking, wireless platforms, and
  telecommunications infrastructure.
• Founded in 1978 and headquartered in Sunnyvale,
  Calif., Trimble has more than 2,000 employees in
  more than 20 countries worldwide.

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What is GPS

• A worldwide radio - navigation system formed
  from a constellation of 24 satellites and their
  ground stations.
• Uses these "man-made stars" as reference points
  to calculate positions accurate to a matter of
  meters. In a sense it's like giving every square
  meter on the planet a unique address.
• These days GPS is finding its way into cars,
  boats, planes, construction equipment, movie
  making gear, farm machinery, even laptop
  computers.
• Soon GPS will become almost as basic as the
  telephone.

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Here's how GPS works in five logical steps

• The basis of GPS is triangulation" from
  satellites.
• To "triangulate," a GPS receiver measures
  distance using the travel time of radio signals.
• To measure travel time, GPS needs very accurate
  timing which it achieves with some tricks.
• Along with distance, you need to know exactly
  where the satellites are in space. High orbits
  and careful monitoring are the secret.
• Finally you must correct for any delays the
  signal experiences as it travels through the
  atmosphere.

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GeoXT Handheld
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GeoXT Handheld

• The Geo XT is a submeter receiver with EVEREST
  multipath rejection technology. It's ideal for
  working under canopy, in urban canyons, or
  anywhere that require high-accuracy data
  collection and maintenance.
• Runs multiple applications and has a familiar
  user interfaceall the advantages to expect from
  a GeoExplorer series handheld.

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Trimble Beacon-on-a-Belt
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Trimble Beacon-on-a-Belt

• Is a robust, compact, real-time differential
  correction receiver.
• Works by receiving GPS differential correction
  information from local MSK beacons and
  transmitting that information to your GPS
  receiver.
• The system includes a beacon receiver, antenna,
  and battery in one system that you wear on your
  belt.
• Built for the rigors of fieldwork, the receiver
  is ergonomic, shockproof, and water-resistant.
• With the receiver, you save time by correcting
  data in real-time as you work.
• You can locate existing assets more quickly, and
  transfer your data directly into your GISwithout
  the need for post processing.

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GPS Pathfinder Office
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GPS Pathfinder Office Software

• The GPS Pathfinder Office software enables you to
  pre-plan your field sessions for more productive
  field work.
• The data dictionary editor creates custom
  pick-lists, automatic repeat feature, and numeric
  values so that collecting many features and
  attributes is easy and accurate.
• In the field, the data dictionary prompts the
  field crew to enter specific information-ensuring
  data integrity and compatibility with your GIS or
  database.

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ECSU SAV Habitat Cooperative Mapping Project

• Photo rectification and interpretation
• GPS and ArcGIS Image Analysis and Spatial Analyst
• Maintain data integrity allowing for survey
  replication
• Field surveys
• Water clarity sampling, temperature, salinity,
  DO, pH
• Distribution, density and species composition of
  SAV
• Signature development and spatial accuracy
  assessment
• Comparative analyses
• Historical database - Ferguson and Wood (1991)
• Refuge staff and local knowledge
• GIS database development
• Digitize polygons
• Map production

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Application of GPS to coastal habitat Research

• Navigating to SAV transect surveying sampling
  stations
• Control Points for Geo-rectification and
  Signature Development
• SAV hunt
• Spatial accuracy assessments

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Mapping and Navigating with Kyle
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Norfolk
Back Bay
Currituck Sound
Elizabeth City
Kitty Hawk Bay
Albemarle Sound
Oregon Inlet
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1000 Meter TransectsCurrituck Sound
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1000 Meter TransectsCurrituck Sound
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1000 Meter TransectsCurrituck Sound
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USFWS National Wildlife RefugesBack Bay and
Mackey Island

• Water Clarity and Water Level
• Control Points for Geo-rectification
• Signature Development
• SAV Hunts
• Back Bay NWR
• Back Bay Restoration Foundation
• False Cape State Park

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Accuracy Assessment Attributes
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Why Use GPS and GIS

• To Protect, enhance and conserve coastal
  fisheries and wildlife habitat
• Ecological value of SAV
• Food
• Refuge
• Improved water quality and clarity

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QUESTIONS?