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Explanation of Size 3 Watershed System TWINSPAN Splits9,8,1,10,11,2,3,4 split from 7,12,14,19,5,6,17,15,16,13,18 due to elevation with 9,8,1,10,11,2,3,4all being in the low elevation while 7,12,14,19,5,6,17,15,16,13,18 were all primarily within themoderate to high elevation zone. Within 9,8,1,10,11,2,3,4 group, 9,8,1 split from 10,11,2,3,4because 9,8,1 were all entirely extremely low in elevation and dominated by flats while10,11,2,3,4 were dominated by gentle slopes and although they were low in elevation they didincluded some areas of moderate elevation. 9 split from 8,1 because 9 had less coarse sedimentflats and less wetflats and more gentle slopes, although all three had a large amount of coarsesediment flats and wet flats. 9 also had a greater proportion of acidic granitic bedrock. 8 splitfrom 1 because 8 had more fine grained sediment and less till, more acidic sedimentary bedrock,much fewer gentle slopes, and more moist wet/flats. 10,11 split from 2,3,4 primarily because ofdifferences in landform and drainage position; both had the same elevation and mixture ofbedrocks. 10,11 drained to Long Island Sound directly or through the Connecticut River and hadmore dry flats on till and more wetflats. 2,3,4 drained directly to the Atlantic coast and had moresummits, upper slopes, sideslopes, and slope bottoms. 10 split from 11 as 10 was coastal, morepredominantly in low elevation and had more acidic granitic bedrock. 11 drained to theConnecticut mainstem and had more had more mafic intermediate granitic bedrock, more coarsesediment, and more wet/moist flats. Although 2,3 and 4 all had predominantly acidic graniticbedrock, 2,3 split from 4 because 2,3 also had substantial amounts of calcareous and moderatelycalcareous bedrock while 4 had no moderately calcareous or calcareous bedrock. 2 split from 3as 3 was lower in elevation and had more moderately calcareous and less calcareous bedrock andless coarse sediment.Within 7,12,14,19,5,6,17,15,16,13,18 group, 7,12,14 split from 19, 5, 6, 17,15,16,13,18 as7,12,14 had a larger percentage of area in the low elevation and were dominated by gentle slopeswith substantial flats and little sideslopes and coves. 7 split from 12, 14 as 7 had some areas inhigher elevation zones, more acidic granitic, and more sideslopes/coves. 12 split from 14 as 14had more patchy surficial, less flats, and although both 12 and 14 had small areas of locallymoderately calcareous bedrock, 12.had larger amounts of these small areas. 19, 5, 6, 17 splitfrom 15,16,13,18 because 15,16,13,18 all had substantial large areas of moderately calcareous orcalcareous bedrock. 15, 16 split from 13, 18 again primarily because of the influence ofcalcareous bedrock and its associated features, with 13 and 18 having morecalcareous/moderately calcareous bedrock than 15, 16. 18 split from 13 as 18 had a much higherpercentage of calcareous/moderately calcareous bedrock (80%) than 13 (44%). 18 also had moresummits, steep slopes, sideslopes and coves. 15 split from 16 because 15 had more higherelevation areas and more acidic granitic bedrock while 16 had more moderatelycalcareous/calcareous bedrock and much more summits, steep slopes, and sideslopes.Summary System Physical DescriptionsThe systems were characterized by different landscape characteristics in elevation , geology,gradient, landform, and connectivity. See LNEsize2.xls and LNEsize3.xls for a more detaileddescription of the physical setting of each watershed system. A short textual summary of thephysical characteristics of each watershed system type is provided in Tables 5 and 6.REVISED 6/2003AQUA-RESULTS-15