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Abstract: The South Florida Water Management District (District or SFWMD) and the U.S. Army Corps of Engineers have built six large treatment wetlands, referred to as Stormwater Treatment Wetlands (STAs), in the Everglades Agricultural Area (EAA) as part of a State and Federal initiative to protect the Everglades (Chimney and Goforth, 2001; Sklar et al., 2005). These treatment wetlands are intended to reduce high phosphorus concentrations in surface runoff coming from the EAA before this water reaches the northern portion of the present-day Everglades, i.e., the Water Conservations Areas. Each STA is subdivided into a number of treatment cells by interior levees. Treatment wetlands reduce the concentration of water-borne pollutants through natural bio-geochemical processes (Kadlec and Wallace, 2009). Wetland biogeochemistry, in turn, is intimately associated with the extent and condition of the wetland’s vegetation community (Reddy and DeLaune, 2009). Because of the important relationship between wetland treatment performance and vegetation, the vegetation communities in the STAs have been monitored throughout their operational histories. This effort was mandated as a condition of STA operating permits and by the Process Development and Engineering section of the District’s Long Term Plan (Burns & McDonnell, 2003). The vegetation communities in the STAs have been monitored using two different approaches: (1) vegetation maps were prepared for each STA based on the spatial distribution of different vegetation types interpreted from aerial photographs and (2) field surveys were conducted at a network of sites within each wetland to catalog plant taxa and assess vegetation areal coverage of the dominant taxa. The field-survey program was initiated as a cost-effective alternative to mapping for characterizing the plant community. For information about the imagery collection access this file: 2014Imagery Collection in STAsFor details how the data was processed see the Lineage section.
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Purpose: This polygon feature class defines the extent and type of vegetation within the Stormwater Treatment Areas (STA -1E, STA -1W, STA-2, STA-3/4, STA-5, and STA-6) using aerial photography flown on March 6 to 7, 2014. The data were collected with the intent of relating the treatment effectiveness of the STAs to the composition of their vegetation communities. The 2014 digital imagery was obtained on May 6 (STA-5/6), and May 17, 2014 [STA-1 East (STA-1E), STA-1 West (STA-1W), STA-2, and STA-3/4] by Aerial Cartographics of America Inc. utilizing a Microsoft UltraCam Eagle digital camera mounted on a Cessna 206 aircraft. The aircraft was flying at an approximate altitude of 15,650 feet above ground level, with 60 percent end lap and 40 percent side lap. The images were collected under conditions minimizing shadows, maximizing light penetration within water bodies, and minimizing sun glare from water surface. The images are free of smoke, clouds, and cloud shadows. Acquisition took place when the sun angle was between 25 and 55 degrees above the horizon. The raw imagery has a ground sampling distance of 12 inches. Raw images were processed using Vexcel UltraMap (version 3.0, Microsoft Corporation, Redmond, Washington) to Level 3 TIFFs. The four color bands are a four-band stack (red, green, blue, and intensity) of level 3 images. Vegetation cover maps for the six STAs were produced using unsupervised classification of the color infrared bands of this imagery. Image processing software (ERDAS Imagine, 2011, Intergraph Corporation, Huntsville, Alabama) was used to reclassify, filter, and aggregate the initial classification. Expert knowledge and ground-truthing of vegetation composition were employed to conduct final edits, calculate acreage, and output results cartographically using geographic information system software (ArcGIS version 10.2, ESRI, Redlands, California).