Atlantic coast joint venture waterfowl implementation plan
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Figure 3.1. Percent change of palustrine forested wetlands in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. 
points that need to be considered when examining the spatial pattern of change for any of the wetland classes. First, model fit, although statistically significant, was better for some classes than others. Specifically, Koneff and Royle (2004) state that model fit was best for estuarine emergent, lacustrine, and palustrine forested wetland classes. Model fit was poorer for palustrine emergent, scrub-shrub, and unconsolidated bottom classes. Second, spatially the model fit was poorer in the mountainous regions of the JV where there were fewer sample plots. Patterns from the Appalachian, Green and White Mountain regions should be viewed with caution and would require field validation before broad generalizations can be made. Maps depicting percent change between the 1970s and 1990s are presented (Figs 3.1 – 3.6). These spatially explicit maps also allow us to summarize wetland changes by any administrative or eco-regional boundary within the ACJV. For example, wetland change can be summarized by Bird Conservation Regions (BCRs, Table 3.2). 3.2 Status and Trends of Other Habitat Types Unfortunately, there have been no comparable monitoring efforts in the United States to monitor changes in other habitat types (i.e., uplands) as has been done with wetlands. Fortunately, two data sets exist that allowed us to assess changes to other habitat types using coarse land use/land cover classifications (Anderson Level II). We used USGS Land Use and Land Cover (LULC) data derived from circa mid-1970s to mid-1980s aerial photo-interpretation to represent the baseline condition for the ACJV that corresponds to the time period that NAWMP assumes provided adequate waterfowl populations. Minimum mapping units for LULC vary from 4 ha (10 acres) for man-made features to 16 ha (40 acres) for natural features (http://edc.usgs.gov/products/landcover/lulc.html). The original classification had 21 categories of land cover (Table 3.3). The most recent comprehensive land cover data available for the ACJV is the USGSs 1992 National Land Cover Data (NLCD, http://landcover.usgs.gov/prodescription.asp). These data were derived from early- to mid-1990s Landsat Thematic Mapper (TM) satellite imagery. A modified Anderson Level II classification scheme resulting in 21 land cover classes were mapped consistently across the U.S. (Table 3.4). Unlike the LULC that was mapped as polygons, the NLCD is a raster data set with a spatial resolution of 0.09 ha (0.22 acre). In order to conduct these analyses the LULC data were converted to a raster data set with a spatial resolution of 0.09 ha (0.22 acre) to match the NLCD. The different classification schemes of the LULC and NLCD were cross-walked to yield a common classification of 15 land cover types. Each resulting class in the re-coded LULC data set was used as a mask to determine how that specific land cover type had changed between the mid-1970s to mid-1990s (Table 3.5). It is important to note that not all land cover categories were able to be reconciled between the two data sets. Specifically, the NLCD data set had a category for Urban/Recreational Grasses; however, it was not clear how such pixels had been classified in the LULC data set. F  igure 3.2. Percent change of estuarine emergent wetlands in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes.
Figure 3.3. Percent change of lacustrine wetlands in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Figure 3.4. Percent change of palustrine emergent wetlands in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Figure 3.5. Percent change of palustrine scrub-shrub wetlands in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Figure 3.6. Percent change of palustrine unconsolidate bottom wetlands (e.g., ponds) in the ACJV at a resolution of 10.36 km2. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Table 3.2. Predicted area (ha) and percent change of six wetlands classes in the ACJV for between the 1970s and 1990s summarized by Bird Conservation Region (BCR). Bold values are standard errors of the predictions expressed as percentage of predicted wetland area. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Taken from Koneff and Royle (2004).
1 BCR Abbreviations – LGL: Lower Great Lakes / St. Lawrence Plain (13), ANF: Atlantic Northern Forest (14), SCP: Southeastern Coastal Plain (27), AMT: Appalachian Mountains (28), PMT: Piedmont (29), NMC: New England / Mid-Atlantic Coast (30), PFL: Peninsular Florida (31) Table 3.2 (cont.). Predicted area (ha) and percent change of six wetlands classes in the ACJV for between the 1970s and 1990s summarized by Bird Conservation Region (BCR). Bold values are standard errors of the predictions expressed as percentage of predicted wetland area. Predicted percent change reflects a combination of conversion both to and from upland as well as to and from other wetland classes. Taken from Koneff and Royle (2004).
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