LAND COVER INVESTIGATION

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LAND COVER INVESTIGATION
Mapping
Data Collection
Manual and Computer-aided Mapping and Change Over
Time Protocols
Land Cover Sample Site and Biometry Protocols
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LAND COVER INVESTIGATION

• Collect MANY Land Cover Sample Sites.
• Map your GLOBE Study Site using the data and
  topographic maps, aerial photos, etc. with manual
  mapping or computer-aided mapping.
• Carry out an accuracy assessment.
• Analyze change in two images several years apart.

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LAND COVER SAMPLE SITE PROTOCOL
What you need in the field

• GPS
• compass
• MUC Field Guide or MUC System Table and MUC
  Glossary of Terms
• camera
• pen or pencil
• Land Cover Sample Site and GPS Data Sheets
• clipboard

• Student Field Guides for Land Cover Sample Site,
  GPS and Biometry Protocol
• knowledge of your individual pace
• vegetation field guides
• markers for permanent sites
• 50m tape measure
• flags

MUC-A-THON (no Biometry) quick and easy minimum.
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LAND COVER SAMPLE SITE PROTOCOL

• 90m X 90m
• Homogeneous land cover (same MUC throughout)
• At least one per land cover type found in your
  Study Site
• Three observations
• latitude, longitude, elevation (GPS)
• MUC
• photos

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LAND COVER SAMPLE SITE PROTOCOL
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LAND COVER SAMPLE SITES

• The thorough study in a homogeneous site
• mark the four corners of your 90m x 90m site and
  the four corners of the center 30m x 30m pixel
• pace both diagonals and collect canopy and ground
  cover data
• measure the heights of the dominant land cover(s)
  (trees, shrubs and/or graminoids)
• determine MUC
• take GPS measurements
• take photos in the four cardinal directions

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LAND COVER SAMPLE SITES

• The MUC-A-THON quick and easy
• pace (N, W, E, S) into the center of a
  homogeneous site (at least 45m) from a different
  land cover type (ex. road)
• take GPS measurements
• take photos in the four cardinal directions
• determine MUC
• Cannot determine MUC?
• pace the diagonals, collect canopy and ground
  cover data, take any height measurements that you
  need OR
• find another site where you do not need to take
  measurements

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USING GPS IN A LAND COVER SAMPLE SITE
We need to compare each Land Cover Sample Site on
the ground to the corresponding area on the image.

• If we take the average of 5 minutes of GPS
  readings, our position is accurate to about 5m.
• It is impossible to determine the exact corner
  location of a single pixel on the ground.
• By collecting GPS data in the center of the site,
  we know that within the positional accuracy of
  the imagery and ground, the center pixel is
  within the 90m x 90m Land Cover Sample.

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GPS PROTOCOL

• Stand at the center of the site
• Record the GPS measurements (to the highest
  number of decimal places for your GPS) once per
  minute for 5 minutes
• Average the readings
• Report to the highest decimal place (at least 4)
• Use the offset GPS Protocol if you cannot get a
  reading from the center of the site

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BIOMETRY PROTOCOL

• Vegetation measurements
• canopy (tree and/or shrub) and ground cover
• tree, shrub and/or graminoid height
• tree circumference
• graminoid biomass
• All relevant Biometry measurements should be
  taken in order to determine and/or verify the
  correct land cover class.
• After that, its up to you!

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BIOMETRY EXAMPLES
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SITE SELECTION AND SET-UP

• Determine if it is 90m x 90m
• Take biometry measurements along diagonals of
  center 30m x 30m pixel
• four student groups
• one along each diagonal
• combine data

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PACING

• Convenient measurement of distance - no need to
  take along a meter tape
• One pace 2 steps
• To find key number of paces
• stretch out a 50m tape
• walk along it three times and average the number
  of paces you find for each of these measurements
• 30m length of one side of a sampling pixel
• 45m distance to the center of a Land Cover
  Sample Site from one side
• 21.2m one-half of the center pixel diagonal
  (gives you how many canopy and ground cover
  measurements to make)

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PACING
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MARKING YOUR SITE (optional)
Establish the center of your square by pacing the
diagonal transects of the square and placing a
marker where the two paths intersect. You may use
string to make these diagonals. Also note that
the two diagonals should be of equal length.
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MAKING AND USING A DENSIOMETER
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MAKING AND USING A DENSIOMETER
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GROUND AND CANOPY COVER

• What you need in the field
• tubular densiometer
• Tree and/or Shrub Canopy Cover and Ground Cover
  Data Sheet(s)
• pen or pencil
• compass
• species ID keys or local species guides
• clipboard

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GROUND AND CANOPY COVER

• From the center, at every pace along the
  half-diagonal

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GROUND AND CANOPY COVER

• look up through densiometer crosshairs
• record a (), T or SB if you see canopy
• record if it is E or D
• record species or common name
• no canopy, record (-)
• look down for vegetation touching your legs or
  feet below the knee
• record B or G for rooted (live) veg.
• record GD, FB, OG, SB, DS
• forb examples clover, sunflowers, ferns, and
  milkweeds
• record (-) for no ground cover

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MAKING AND USING A CLINOMETER
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MAKING AND USING A CLINOMETER
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VEGETATION HEIGHT

• What you need in the field
• 50 m measuring tape
• flexible measuring tape
• small bean bag
• Graminoid, Tree and Shrub Height Data Sheet
• pen or pencil
• permanent tree markers (optional)
• clinometer
• species ID keys or other local species guides
• blindfold

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VEGETATION HEIGHT

• Graminoid and shrub height
• use a bean bag to choose samples
• average three measurements
• Tree height (for level ground)
• choose tallest tree shortest tree that reaches
  canopy, three in between
• dominant and co-dominant species
• be at least as far away as it is tall
• clinometer close to 30?

Note When the tree base and your feet are not
at the same height, see the field guides for
other methods!
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VEGETATION HEIGHT

• measure three times
• average must be within 1m of the heights
• measure the same trees, report heights
  circumferences in the same order

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TREE CIRCUMFERENCE

• What you need in the field
• flexible measuring tape
• Tree Circumference Data Sheet
• pen or pencil
• species ID keys or other local species guides

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TREE CIRCUMFERENCE

• Tree circumference
• same trees as tree height
• measured at 1.35m

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GRAMINOID BIOMASS

• What you need in the field
• small bean bag
• Graminoid Biomass Data Sheet
• pen or pencil
• blindfold
• grass clippers or strong scissors
• small brown paper bags
• species ID keys or other local species guides
• IN THE CLASSROOM balance and drying oven

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GRAMINOID BIOMASS

• Within random 1m square
• clip all attached graminoid vegetation at ground
• discard leaves, twigs, non-grasses
• sort into brown (senescent) and green (living)
  clippings
• place separately into brown paper bags
• repeat twice for a total of 3 samples
• In the classroom
• dry the bags in a drying oven (50-70 C) until
  mass no longer changes
• calculate mass of brown and green graminoids

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MAPPING

• Manual Mapping
• satellite image (print)
• transparency markers
• tranparency
• reference data, maps, aerial photos, etc.
• Computer-aided Mapping (Advanced)

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MAP USES

• studying the habitat of a certain animal or plant
• looking at the succession of fields to forests
• studying the rate of growth of a particular
  village, town or city
• looking at the amount of undeveloped land
• deciding how to protect water resources
• deciding where to plant certain crops during the
  next growing season.
• deciding new school boundaries
• choosing where to connect recreational trails to
  create one continuous system
• deciding how to efficiently run public
  transportation
• studying another specific question

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MAPPING
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MAPPING
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MAPPING
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LANDSAT IMAGE
Using the Land Cover data entry pages, you can
request your GLOBE Study Site image once you have
reported 250 measurements and submitted the GPS
coordinates of your school location.
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MANUAL MAPPING

• Assemble your materials
• Place transparency over the satellite image
• Using topographic maps and aerial photographs,
  start to outline areas
• To start, use common names but work up to MUC
  classes!

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MANUAL MAPPING

• Identify Water Bodies

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MANUAL MAPPING

• Transportation Features Are Added

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MANUAL MAPPING

• Buildings and Developed Areas are Added

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MANUAL MAPPING

• Vegetated Areas and Other Features are Added

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MANUAL MAPPING

• Final Product - Student Classified Land Cover Map

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MANUAL MAPPING
Outline Roads
Outline Water
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MANUAL MAPPING
Outline Other Classes
Final Land Cover Map
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MANUAL MAPPING
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MANUAL MAPPING
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ACCURACY ASSESSMENT
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ACCURACY ASSESSMENT
After we collect many Land Cover Sample Sites
throughout the GLOBE Study Site, perform an
accuracy assessment on the land cover type map.
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ACCURACY ASSESSMENT
Using the Land Cover Sample Site data, complete
the Accuracy Assessment Work Sheet.
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ACCURACY ASSESSMENT
Build an empty difference/error matrix.
Label the matrix with the titles and MUC classes.
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ACCURACY ASSESSMENT
Tally each row of data.
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ACCURACY ASSESSMENT
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ACCURACY ASSESSMENT

• Calculate
• Row Totals
• Column Totals
• Total Data Samples

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ACCURACY ASSESSMENT
Overall Accuracy indicates how well the map
identifies all land cover types on the ground.
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ACCURACY ASSESSMENT
Producers Accuracy indicates what percentage of
the time a particular land cover type on the
ground was identified as that land cover type on
the map. It expresses how well the map producer
identified a land cover type on the map from the
satellite imagery data.
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ACCURACY ASSESSMENT
Users Accuracy indicates what percentage of the
time a particular land cover type on the map is
really that land cover type on the ground. It
expresses how well a person using the map will
find that land cover type on the ground.
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ACCURACY ASSESSMENT
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ACCURACY ASSESSMENT
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ACCURACY ASSESSMENT