Vegetation - Suisun Marsh - 2006 [ds500] GIS Dataset

Topics and Keywords

Themes or categories of the resource environment, biota

* Content type Downloadable Data

Place keywords San Francisco Bay Delta, Bay Delta, Suisun Marsh, Solano County, California

Theme keywords wetland, land cover, Vegetation, tidal, marsh

Theme keywords environment, biota

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Citation

Title Vegetation - Suisun Marsh - 2006 [ds500]

Publication date 2014-08-22

Presentation formats digital map

FGDC geospatial presentation format vector digital data

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Citation Contacts

Responsible party

Organization's name California Department of Fish and Wildlife (CDFW)
Contact's role originator

Responsible party

Individual's name Vegetation Classification and Mapping Program
Organization's name California Department of Fish and Wildlife (CDFW)
Contact's position Program Lead
Contact's role point of contact

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Resource Details

Dataset languages English(UNITED STATES)

Dataset character set utf8 - 8 bit UCS Transfer Format

Status completed

Spatial representation type vector

Supplemental information

Orthorectified, true color imagery was flown in June 2006 to mimic as close as possible the June 1999 and June 2003 Suisun imagery time frame and plant phenology. This imagery was received as 427 high quality, individual, flight line ortho-photographs. The aerial imagery was interpreted and changes were made to the vegetation polygon shapefile using ArcMap 9.2 (ESRI). The criteria for a polygon to be considered "changed" were first laid out in the change detection report for 2003 (Vaghti and Keeler-Wolf 2004), and are repeated here: The following changes were considered significant and consistently interpretable, and were assessed: " A greater than 20% change in acreage of an exiting small polygon (<1 acre) " A greater than 10% change in acreage of a mid-sized polygon (1-5 acres) " A greater than 5% change in a large polygon (>5 acres) " A type conversion of a vegetation polygon dominated by perennial species. Type conversion, as defined here, occurs when a previously mapped vegetation type dominated by perennial species has changed based on the decision rules set forth in the vegetation mapping unit key defined in Table 5 of Vegetation Mapping of Suisun Marsh, Solano County (Keeler-Wolf et al. 2000), or when an annual species dominated vegetation type is converted to a perennial vegetation type. " A persistent physical change has altered any vegetation polygon and partially or entirely replaced it with a non-vegetated area (non-vegetated areas include buildings, dredged ditches, new levees, roads, or other human engineered structures). " A change in management style, which includes a conversion or restoration from an actively managed situation (annual burning, disking, plowing, flooding, or other management practice which annually disturbs the vegetation) to a passively managed, or un-managed, situation. The following changes were considered non-significant and/or unreliably interpretable and were not assessed: " Annual to annual type conversion were not considered because of the vagaries of climate on annual vegetation. Appendix 2 highlights these excluded types in yellow. " Polygons that are regularly heavily managed by annual burning, disking, flooding, or other means were not considered. These changes, unless they show some direction (e.g., from passive management to active, or vice versa), are considered regular management perturbations and maintain the same general vegetation pattern through regular disturbance. A copy of the 2003 vegetation polygon shapefile was made and modified for the 2003-2006 change detection and then it was linked to a new 2006 Microsoft Access table for data entry. For consistency the attributes and vegetation types for the 2006 change detection remained the same as in 2003. When changes in size or shape of polygons were detected, they were cut using the "Cut Polygon Features" task and then merged using the "Merge" option in ArcMap. 250 releve field samples were collected in 1999. 250 rapid assessment field samples were collected in 2000. 99 rapid assessment field samples were collected in 2003. 98 of the origional 250 releves were resampled in 2006. The complete report can be viewed at: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=48107. The attributes described in the 2006 Suisun Marsh Vegetation Change Detection report differ slightly to what is actually presented in this dataset. All reference to the 1999 and 2003 vegetation maps (see Appendix 1 in the report) have been removed from this dataset, which now only reflects data for the 2006 Suisun Marsh vegetation. This is the third update since the orginal map was made in 1999. The first update was conducted one year after the initial aerial photo-interpretation (see ds161), is described in Vegetation Mapping of Suisun Marsh, Solano County (Keeler-Wolf and Vaghti, 2000): https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=24570. The second update, done three years later in 2003 (see ds162), is summarized in Suisun Marsh Vegetation Mapping Change Detection 2003 (Vaghti and Keeler-Wolf 2004): https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18254. The fourth update, done in 2009 (see ds711), is summarized in 2009 Vegetation Map Update for Suisun Marsh, Solano County, California (Boul and Keeler-Wolf 2012): https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=48108. The fifth update was done in 2012 (the vegetation map and report are not yet available to the public).

* Processing environment Version 6.2 (Build 9200) ; Esri ArcGIS 10.5.1.7333

Credits

Vegetation Classification and Mapping Program (VegCAMP), Department of Fish and Wildlife.

ArcGIS item properties