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Seasonal Wetlands

Of the wetland delineations we made along 60 transects in seasonal wetlands (six transects in each of ten wetlands), 44 of the invertebrate delineations were within 2 m of the standard delineations (Figure 3). For the five seasonal wetlands in grassland, 12 of 30 of the invertebrate delineations were at the same location as the standard delineations, and 18 were closer to the wetland's center; not a single invertebrate delineation in grassland was on the upland side of the standard delineation (Figure 4). In the five cropland wetlands, six invertebrate delineations were at the same location as the standard delineations, while eight were on the wetland side and 16 were on the upland side (Figures 3 and 5). For both groups (seasonal wetlands in cropland and seasonal wetlands in grassland), the relative elevations of the invertebrate delineations were more consistent (i.e., had lower standard deviations) within wetlands than the elevations of the standard delineations (Figure 6). Even for individual wetlands, this held true with only one exception, a seasonal wetland in cropland.

Temporary Wetlands

Of the ten temporary wetlands we sampled, we were able to perform standard delineations in only seven, all five grassland wetlands and two cropland wetlands. We were unable to perform standard delineations in the three cropland wetlands due to severe disturbance of indicators by tillage. In two of these three wetlands, we were also unable to perform our invertebrate delineations due to an absence of invertebrate remains in our samples.

In the seven temporary wetlands in which we were able to perform both invertebrate and standard delineations, delineations followed the same general trends we observed for seasonal wetlands. Of the wetland delineations we made along the 42 transects (six transects in each of the seven temporary wetlands), 30 of the invertebrate delineations were within 1 m of the standard delineations and 37 were within 2 m (Figure 3). Just as for seasonal wetlands in grassland, all of the invertebrate delineations in the temporary wetlands in grassland were either at the same location as the standard delineations (6 of 30) or were closer to the wetland's center (the remaining 24). Once again, not a single invertebrate delineation was on the upland side of the standard delineation in grassland wetlands. In the two cropland wetlands for which we were able to perform the standard delineations, three of the invertebrate delineations were at the same location as the standard delineations, five were on the wetland side, and four were on the upland side (Figure 3). Without exception, the relative elevations from our invertebrate delineations of temporary wetlands in cropland and grassland had lower standard deviations within wetlands than the elevations from our standard delineations (Figure 6).