The Cooperative Land Cover map integrates data from multiple sources.
All sources were crosswalked into the Florida Land Cover Classification System (Kawula 2009)
All source datasets were received and processed as vector data.
We used a set of standard geoprocessing and topology operations in ArcGIS 9.3 to
ensure no overlapping features within or among datasets. All data were projected
into the Florida Albers custom coordinate system with NAD 1983 HARN datum. We
applied a minimum mapping unit of 0.5 acres and dissolved each polygon <0.5
acres into its largest neighboring polygon except for scrub, pine rockland and
upland glade polygons for which we applied a minimum mapping unit of 0.1 acres.
Finally, lines between neighboring polygons with the same classification were
dissolved. Based on our review of each dataset, we sometimes made other
modifications as described in: Florida Natural Areas Inventory, 2010. Development
of a Cooperative Land Cover Map: Final Report (available from FNAI upon request).
Explanation of confidence categories:
We evaluated datasets based on metadata, discussions with data providers and a
general review of the spatial accuracy and classification. Based on this review we
assigned a confidence category to each dataset that indicated how or if the
dataset, or certain classes within the dataset, would be integrated into the final land
cover map. A confidence category of 1 indicates the highest level of confidence;
these data spatially superseded all other intersecting sources. Category 2 data took
precedence over statewide datasets (FLUCCS, FLVEG) but did not supersede
category 1. Category 3 data were used with review and revision. Category 4 data
were used to identify additional areas for aerial photo review and help interpret
classification during the review process; these data, however, were not directly
integrated into the final map.
Process Date:
Aerial Photography Review of Focal Communities:
Areas within existing source data in categories 1 through 3 (non-ancillary sources)
were excluded from the set of polygons to be reviewed. Scrub, scrubby flatwoods,
sandhill, dry prairie and mesic flatwoods (in SWF and SF only) were reviewed
simultaneously as a single set of review polygons. We inspected the review
polygons as well as proximal areas with the latest high resolution aerial photography
(2006 - 2009) and other ancillary data sources including aerial photography from
2004, 1999 and 1995, topographic maps, county soils maps and other land cover
datasets. We reviewed areas at a scale of 1:5000 with a minimum mapping unit of
0.5 acres with exception to include smaller polygons for scrub and pine rockland.
We spatially edited polygons and delineated new polygons where necessary to
identify focal communities and then assigned the polygon a land cover type. We
deleted polygons from the set of review polygons that did not represent priority
communities and were otherwise correctly classified. We always assigned a land
cover type to polygons classified as FLUCCS Coastal Scrub, Xeric Oak, Sand Pine,
or Longleaf Pine - Xeric Oak; in addition almost all review polygons in the SWF and
SF districts were assigned a land cover type. Any deleted polygon will default to its
FLUCCS class in the final land cover map.
FNAI biologists familiar with the focal communities both on the ground and through
aerial photo interpretation performed the initial polygon inspections. A second
reviewer then re-inspected the polygons that were assigned as one of the focal
communities. We also checked all locations from the FNAI element occurrence
database that reference scrub, scrubby flatwoods, sandhill or dry prairie.
We identified areas that appeared to be functioning as viable natural communities.
Areas that were historically scrub or sandhill but are now disturbed so that they likely
no longer support their characteristic ecological elements or that have succeeded
to another natural community type were excluded or classified as another land
cover type. We classified many former sandhills as successional hardwood forest.
We classified pine plantation as scrub or sandhill where it appeared to function
ecologically as a natural community. This was especially true of planted sand pine
scrub which can tolerate a high degree of disturbance. We examined aerial
photographs from 1995 and 1999 to help determine the level of past ground
disturbance. We did not include small patches within residential areas, although if
there appeared to be functional large patches within low density or rural residential
areas we included them. We mapped only obvious patches of scrubby flatwoods.
This community was sometimes difficult to distinguish from scrub and we did not
follow strict criteria for distinguishing the two. For dry prairie we strictly followed the
FNAI definition of treeless areas of low shrubs and grasses within the buffered
historic dry prairie extent. Many prairie-like areas are pine flatwoods in which trees
have been removed. To determine dry prairie from flatwoods we considered
geographic position, shrub patterns, proximity of wetlands and overall landscape
context.
For more details: Florida Natural Areas Inventory, 2010. Development of a
Cooperative Land Cover Map: Final Report (available from FNAI upon request).
Process Date:
Assemblage of Data Sources into Final Map:
We separated the data into 3 components for assembly into statewide land cover:
1) Local Source data, which consisted of all local sources with confidence category
1 through 3; 2) FNAI Review data, which consisted of all datasets that we
inspected and classified through aerial photo review; and 3) FLUCCS. The
SWFWMD published a new version of FLUCCS based on 2008 photography in
spring 2010. Although we used 2007 FLUCCS for aerial photo review and
comparative analyses in that district, we incorporated the 2008 data in the final land
cover map. We converted all datasets into 15 m ESRI grids and combined them
based on the following rules: 1) Local Source data with confidence category 1 and
2 superseded FNAI Review data; 2) FNAI Review data superseded Local Source
data with confidence category 3; 3) all Local Source 1 through 3 and FNAI Review
data superseded FLUCCS.
Process Date:
GeoPlan downloaded this layer from FNAI on December 15th, 2011. The data was
in shapefile format in Albers HPGN projection.
-Upcased all text fields
-Renamed from Focal_NC_Map_CLC_v1_1 to CLC_JUL10
-Added DESCRIPT field based on LCNAME field
-Added FGDLAQDATE and calculated based on date GeoPlan acquired data from source.
Process Date: 20120502
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