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Tables |
Table 5. |
Mean number of midges per square meter by study reach and aquatic strata. For sample sizes, refer to Table 1. SE=standard error. |
|
Study reach
|
Year
|
Backwater
contiguous |
±
1 SE |
Impoundeda
|
±
1 SE |
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| Pool 4 |
1993
|
203
|
32
|
364
|
38
|
87
|
50
|
40
|
34
|
|
1994
|
233
|
61
|
182
|
22
|
135
|
80
|
23
|
21
|
|
|
1995
|
116
|
17
|
78
|
14
|
12
|
5
|
10
|
6
|
|
|
1996
|
47
|
12
|
37
|
11
|
33
|
17
|
25
|
13
|
|
|
1997
|
81
|
20
|
190
|
43
|
5
|
4
|
7
|
7
|
|
|
1998
|
98
|
12
|
324
|
51
|
24
|
14
|
2
|
2
|
|
|
1999
|
107
|
22
|
243
|
36
|
33
|
17
|
56
|
46
|
|
|
2000
|
82
|
14
|
59
|
12
|
77
|
22
|
77
|
65
|
|
|
|
2001
|
32
|
9
|
88
|
15
|
31
|
20
|
0
|
0
|
|
2002
|
90
|
20
|
68
|
15
|
52
|
36
|
0
|
0
|
|
|
2003b
|
—
|
—
|
—
|
—
|
—
|
—
|
—
|
—
|
|
|
2004
|
89
|
15
|
113
|
20
|
44
|
28
|
64
|
30
|
|
| aImpounded
area for Pool 4 is Lake Pepin, a Tributary Delta Lake. bSampling not conducted in 2003 because of budget constraints. |
|||||||||
|
Study reach
|
Year
|
Backwater
contiguous |
±
1 SE |
Impounded
|
±
1 SE |
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| Pool 8 |
1993
|
40
|
11
|
66
|
8
|
42
|
13
|
10
|
8
|
|
1994
|
38
|
11
|
12
|
7
|
57
|
50
|
3
|
2
|
|
|
1995
|
12
|
4
|
13
|
4
|
9
|
7
|
0
|
0
|
|
|
1996
|
19
|
6
|
20
|
5
|
1
|
1
|
4
|
3
|
|
|
1997
|
20
|
7
|
39
|
7
|
10
|
6
|
6
|
6
|
|
|
1998
|
100
|
18
|
82
|
11
|
83
|
40
|
33
|
15
|
|
|
1999
|
46
|
16
|
53
|
14
|
24
|
7
|
38
|
34
|
|
|
2000
|
84
|
23
|
20
|
7
|
32
|
13
|
19
|
12
|
|
|
2001
|
97
|
25
|
26
|
7
|
8
|
4
|
0
|
0
|
|
| 2002 |
72
|
13
|
68
|
17
|
36
|
18
|
54
|
32
|
|
| 2003 |
92
|
32
|
13
|
3
|
6
|
2
|
2
|
2
|
|
|
2004
|
87
|
25
|
625
|
138
|
141
|
67
|
4
|
4
|
|
Study reach
|
Year
|
Backwater
contiguous |
±
1 SE |
Impounded
|
±
1 SE |
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| Pool 13 |
1993
|
237
|
56
|
916
|
130
|
18
|
9
|
190
|
135
|
|
1994
|
144
|
43
|
43
|
33
|
8
|
4
|
50
|
40
|
|
|
1995
|
93
|
18
|
19
|
7
|
2
|
2
|
3
|
2
|
|
|
1996
|
53
|
14
|
5
|
3
|
12
|
8
|
4
|
4
|
|
|
1997
|
213
|
99
|
19
|
6
|
0
|
0
|
10
|
9
|
|
|
1998
|
148
|
37
|
61
|
29
|
3
|
2
|
33
|
22
|
|
|
1999
|
698
|
220
|
11
|
4
|
5
|
4
|
4
|
4
|
|
|
2000
|
1664
|
223
|
63
|
30
|
25
|
18
|
8
|
4
|
|
|
|
2001
|
56
|
14
|
22
|
21
|
3
|
3
|
0
|
0
|
|
2002
|
570
|
137
|
12
|
6
|
3
|
2
|
0
|
0
|
|
|
2003
|
416
|
80
|
4
|
2
|
0
|
0
|
0
|
0
|
|
|
2004
|
625
|
135
|
137
|
67
|
11
|
4
|
0
|
0
|
|
Study reach
|
Year
|
Backwater
contiguous |
±
1 SE |
Impounded
|
±
1 SE |
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| Pool 26 |
1993
|
81
|
17
|
136
|
26
|
0
|
0
|
0
|
0
|
|
1994
|
90
|
26
|
46
|
15
|
2
|
1
|
9
|
8
|
|
|
1995
|
48
|
18
|
31
|
15
|
—a
|
—
|
—a
|
—
|
|
|
1996
|
112
|
37
|
48
|
10
|
6
|
4
|
11
|
7
|
|
|
1997
|
106
|
46
|
39
|
11
|
0
|
0
|
6
|
4
|
|
|
1998
|
34
|
11
|
30
|
12
|
1
|
1
|
1
|
1
|
|
|
1999
|
59
|
19
|
42
|
10
|
9
|
6
|
1
|
1
|
|
|
2000
|
82
|
14
|
78
|
15
|
27
|
8
|
17
|
6
|
|
|
|
2001
|
267
|
68
|
149
|
22
|
18
|
6
|
0
|
0
|
|
2002
|
255
|
58
|
313
|
52
|
19
|
9
|
28
|
9
|
|
|
2003b
|
—
|
—
|
—
|
—
|
—
|
—
|
—
|
—
|
|
|
2004
|
104
|
24
|
453
|
53
|
14
|
11
|
15
|
8
|
|
| aSampling
not completed because of high water. bSampling not conducted in 2003 because of budget constraints. |
|||||||||
|
Study reach
|
Year
|
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| Open River Reach |
1993a
|
—
|
—
|
—
|
—
|
|
1994
|
4
|
2
|
8
|
4
|
|
|
1995
|
41
|
12
|
10
|
4
|
|
|
1996
|
21
|
4
|
3
|
2
|
|
|
1997a
|
—
|
—
|
—
|
—
|
|
|
1998
|
5
|
2
|
4
|
2
|
|
|
1999
|
2
|
1
|
6
|
3
|
|
|
2000
|
119
|
30
|
9
|
4
|
|
|
2001b
|
—
|
—
|
—
|
—
|
|
| aSampling
not conducted in 1993 or 1997 because of high water. bSampling discontinued in 2001. |
|||||
|
Study reach
|
Year
|
Backwater
contiguous |
±
1 SE |
Side channel
|
±
1 SE |
Main channel
border |
±
1 SE |
| La Grange Pool |
1993
|
92
|
22
|
26
|
5
|
27
|
10
|
|
1994
|
51
|
9
|
75
|
14
|
58
|
10
|
|
|
1995
|
54
|
24
|
50
|
14
|
15
|
4
|
|
|
1996
|
97
|
21
|
136
|
38
|
175
|
64
|
|
|
1997
|
188
|
58
|
55
|
27
|
64
|
22
|
|
|
1998
|
244
|
68
|
21
|
9
|
25
|
6
|
|
|
1999
|
120
|
43
|
25
|
7
|
13
|
4
|
|
|
2000
|
177
|
62
|
25
|
6
|
18
|
4
|
|
|
|
2001
|
132
|
30
|
73
|
26
|
12
|
4
|
|
2002
|
264
|
51
|
90
|
31
|
21
|
5
|
|
|
2003a
|
—
|
—
|
—
|
—
|
—
|
—
|
|
|
2004
|
167
|
41
|
110
|
27
|
30
|
8
|
|
| aSampling not conducted in 2003 because of budget constraints. | |||||||
Content manager: Jennie Sauer
U.S. Department of the Interior |
U.S. Geological Survey
URL: http://www.umesc.usgs.gov/reports_publications/ltrmp/macro/tables/table05_mean_midges.html
Page Contact Information: Contacting the Upper Midwest Environmental Sciences Center
Page Last Modified:
October 2, 2007
