. Bulletin. Natural history; Natural history. 314 Illinois Natural History Survey Bulletin Vol. 28, Art. Table 4,—Champaign County stream habitats, the extent of their occurrence, and thei^ physical characteristics. Drainage Average Maximum Miles in Area Gradient Depth Current Habitat County (Square (Feet PER (Range in Miles) Mile) Inches) Rivulet and small creek 189 10 7 1-10 Variable Large creek 176 10-200 3 Riftle Sand and fine gravel 1-12 Swift Gravel and boulder 1-12 Swift Pool 4-24 Moderat Deep - 24-48 Sluggish Small river 58 200-400 2 Riffle Sand and gravel 3-18 Swift Boulder
. Bulletin. Natural history; Natural history. 314 Illinois Natural History Survey Bulletin Vol. 28, Art. Table 4,—Champaign County stream habitats, the extent of their occurrence, and thei^ physical characteristics. Drainage Average Maximum Miles in Area Gradient Depth Current Habitat County (Square (Feet PER (Range in Miles) Mile) Inches) Rivulet and small creek 189 10 7 1-10 Variable Large creek 176 10-200 3 Riftle Sand and fine gravel 1-12 Swift Gravel and boulder 1-12 Swift Pool 4-24 Moderat Deep - 24-48 Sluggish Small river 58 200-400 2 Riffle Sand and gravel 3-18 Swift Boulder and rubble - 3-18 Swift Pool Shallow- - - 18-36 Moderat Deep -- 36-96 Sluggish and riffles; moderately deep, smoothly flowing stretches; and long, deep pools. They described each habitat and listed characteristic species of fishes. We prefer a classification based on the same ecological characteristics but having divisions with more easily definable limits, table 4. Rivulets and Small Greeks. — Our rivulets and small creeks include the ver- nal rivulets of Thompson & Hunt and also intermittent streams of slightly greater size. They arise as small open gullies coming off the face of moraim slopes, as seeps in grass waterways, or as discharges at field tiles, fig. 7, draining flat marshy areas. The type that originates at a field tile may have an unusual be- ginning because of the large, and some- times surprisingly deep, hole that is scoured out at the base of the tile. In many cases, the pool contains a large con- centration of fish. Most rivulets and small creeks in Champaign County have been modified by dredging and straightening of the chan-. Fig. 7.—Drain tile mouth and pool on the East Branch of the Salt Fork of the Vermilion River. A tile mouth is Champaign County's analogue of a Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations m
Size: 2057px × 1215px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
