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Vegetation Update Title Page
tree_ftree_f Tables

Table 3.   Percent frequency of occurrence and abundance index of submersed aquatic vegetation by year, study reach, and aquatic strata (n = number of sites, Frq = percent frequency of occurrence, SE = standard error, AI = abundance index). In 1998, sites were selected from depths less than or equal to 3 m.  After 1998, the criteria was changed to less than or equal to 2.5 m; therefore, any sites between 2.5 and 3 m were dropped from the 1998 analysis for comparison purposes. A dash (–) indicates stratum was not sampled.

Pool 4
Contiguous backwater,
upper
Contiguous backwater, lower
Isolated backwater
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
74
32.4
5.5
4.3
0.8
157
68.8
3.7
14.2
1.2
31
87.1
6.1
25.7
3.5
1999
75
29.3
5.3
3.6
0.7
160
66.3
3.8
10.8
0.7
34
76.5
7.4
15.9
2.3
2000
100
18.0
3.9
2.0
0.5
179
64.2
3.6
10.7
0.8
32
81.3
7.0
26.7
4.9
2001
100
14.0
3.5
1.3
0.4
176
71.0
3.4
12.0
0.7
50
76.0
6.1
15.1
1.7
2002
100
16.0
3.7
2.1
0.5
180
67.2
3.5
10.2
0.6
30
83.3
6.9
17.5
2.1
2003a
92
13.0
3.5
1.8
0.5
165
66.7
3.7
16.2
1.3
–
–
–
–
–
2004
102
8.8
2.8
0.9
0.3
181
63.5
3.6
11.3
0.8
32
68.8
8.3
15.1
3.0
2005
90
14.4
3.7
2.2
0.6
108
81.5
3.8
25.2
2.1
20
50.0
11.5
10.6
2.5
2006
90
11.1
3.3
3.6
1.5
110
85.5
3.4
21.1
1.5
11
81.8
12.2
23.3
5.7
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 4
Lake Pepin,
upper
Lake Pepin,
lower
Main channel border, upper
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
57
21.1
5.4
2.3
0.7
29
6.9
4.8
1.0
0.7
9
0.0
0.0
0.0
0.0
1999
65
16.9
4.7
2.3
0.7
35
8.6
4.8
1.6
0.9
12
16.7
11.2
1.1
0.8
2000
75
14.7
4.1
1.3
0.4
75
46.7
5.8
6.4
0.9
30
3.3
3.3
0.2
0.2
2001
75
5.3
2.6
0.4
0.2
75
41.3
5.7
5.9
0.9
30
3.3
3.3
0.4
0.4
2002
75
8.0
3.2
0.7
0.3
75
25.3
5.1
4.0
0.8
30
3.3
3.3
0.6
0.6
2003a
–
–
–
–
–
–
–
–
–
–
26
0.0
0.0
0.0
0.0
2004
77
7.8
3.1
1.2
0.5
77
9.1
3.3
0.8
0.3
31
0.0
0.0
0.0
0.0
2005
59
10.2
4.0
1.0
0.4
50
8.0
3.9
0.9
0.5
20
0.0
0.0
0.0
0.0
2006
60
18.3
5.0
2.5
0.7
50
16.0
5.2
1.9
0.6
20
5.0
5.0
0.3
0.3
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 4
Main channel border,
lower
Secondary channel,
upper
Secondary channel,
lower
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
37
10.8
5.2
1.8
0.7
47
4.3
3.0
0.3
0.2
65
35.4
6.0
6.8
1.4
1999
48
20.8
5.9
2.4
0.8
61
0.0
0.0
0.0
0.0
59
37.3
6.3
5.2
1.0
2000
40
22.5
6.7
2.4
0.8
40
0.0
0.0
0.0
0.0
60
45.0
6.5
7.2
1.2
2001
40
22.5
6.7
4.9
1.5
40
0.0
0.0
0.0
0.0
60
31.7
6.1
5.2
1.1
2002
40
20.0
6.4
2.8
1.0
40
5.0
3.5
0.5
0.4
60
25.0
5.6
3.7
0.9
2003a
23
26.1
9.4
7.3
3.0
39
0.0
0.0
0.0
0.0
53
32.1
6.5
6.3
1.5
2004
41
14.6
5.6
1.9
0.8
41
0.0
0.0
0.0
0.0
61
34.4
6.1
5.4
1.0
2005
30
10.0
5.6
2.0
1.3
30
0.0
0.0
0.0
0.0
39
38.5
7.9
9.0
2.2
2006
30
10.0
5.6
1.6
1.0
30
3.3
3.3
0.2
0.2
40
55.0
8.0
9.6
1.6
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 8
Contiguous backwater
Isolated backwater
Impounded
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
172
82.0
2.9
19.6
1.3
28
96.4
3.6
25.5
3.1
170
33.5
3.6
5.2
0.7
1999
172
92.4
2.0
19.7
1.0
28
92.9
5.0
19.8
2.3
225
44.9
3.3
6.6
0.6
2000
175
74.9
3.3
14.4
0.9
30
93.3
4.6
23.2
3.2
225
34.7
3.2
5.3
0.5
2001
175
76.0
3.2
12.6
0.7
50
92.0
3.9
21.8
1.9
225
36.9
3.2
5.8
0.6
2002
174
76.4
3.2
14.8
0.8
26
88.5
6.4
23.6
3.4
224
47.3
3.3
9.3
0.8
2003
174
78.2
3.1
13.2
0.7
30
86.7
6.3
16.5
1.4
225
50.7
3.3
9.6
0.7
2004
175
80.0
3.0
17.0
1.0
29
86.2
6.5
16.1
1.8
225
56.0
3.3
11.0
0.8
2005
110
84.5
3.5
20.4
1.1
20
90.0
6.9
22.9
2.5
185
75.7
3.2
18.1
1.0
2006
108
88.9
3.0
21.0
1.1
16
87.5
8.5
20.9
3.5
185
71.4
3.3
17.5
1.0

 

Pool 8
Main channel border
Secondary channel
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
53
18.9
5.4
3.1
1.0
93
35.5
5.0
7.1
1.3
1999
70
25.7
5.3
3.8
0.9
100
36.0
4.8
5.2
0.8
2000
99
30.3
4.6
3.7
0.6
120
32.5
4.3
4.5
0.6
2001
100
24.0
4.3
3.5
0.8
120
22.5
3.8
3.1
0.6
2002
100
17.0
3.8
2.9
0.7
120
29.2
4.2
4.5
0.7
2003
100
15.0
3.6
2.7
0.7
120
28.3
4.1
4.8
0.8
2004
100
21.0
4.1
3.5
0.7
120
30.0
4.2
4.3
0.7
2005
70
24.3
5.2
4.4
1.1
65
32.3
5.8
6.2
1.2
2006
70
20.0
4.8
4.1
1.1
65
46.2
6.2
7.9
1.4

 

Pool 13
Contiguous backwater
Isolated backwater
Impounded
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
170
52.4
3.8
9.0
0.8
28
71.4
8.7
15.4
2.3
209
42.6
3.4
8.2
0.8
1999
170
51.8
3.8
9.0
0.8
30
56.7
9.2
18.1
4.3
210
42.4
3.4
8.0
0.8
2000
198
58.1
3.5
11.0
0.9
30
53.3
9.3
11.6
2.4
210
40.5
3.4
8.1
0.7
2001
198
55.6
3.5
12.2
1.1
59
57.6
6.5
11.1
1.7
209
38.3
3.4
9.4
1.0
2002
200
51.5
3.5
12.0
1.1
30
66.7
8.8
11.6
1.7
209
44.5
3.4
12.7
1.2
2003
200
56.0
3.5
13.3
1.0
30
53.3
9.3
19.5
4.6
210
36.7
3.3
8.6
0.9
2004
220
60.9
3.3
12.4
0.9
34
50.0
8.7
11.1
3.0
236
46.2
3.3
11.0
1.0
2005
120
67.5
4.3
15.7
1.4
25
72.0
9.2
22.6
3.8
175
59.4
3.7
14.8
1.2
2006
120
65.8
4.3
14.0
1.2
25
68.0
9.5
15.1
2.2
175
69.7
3.5
14.8
0.9

 

Pool 13
Main channel border
Secondary channel
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
62
8.1
3.5
0.9
0.4
62
14.5
4.5
1.7
0.6
1999
70
11.4
3.8
1.7
0.6
70
10.0
3.6
1.1
0.4
2000
70
14.3
4.2
2.3
0.8
70
4.3
2.4
0.3
0.2
2001
70
10.0
3.6
1.9
0.8
70
14.3
4.2
1.5
0.5
2002
70
7.1
3.1
1.0
0.5
70
10.0
3.6
1.1
0.4
2003
70
7.1
3.1
1.4
0.7
70
11.4
3.8
1.4
0.5
2004
79
12.7
3.8
1.3
0.4
79
10.1
3.4
1.3
0.5
2005
80
12.5
3.7
2.5
0.8
50
14.0
5.0
1.7
0.6
2006
80
20.0
4.5
3.0
0.7
50
18.0
5.5
3.2
1.3

 

Pool 26
Contiguous backwater
Isolated backwater,
Illinois River
Isolated backwater, Mississippi River
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
50
2.0
2.0
0.1
0.1
160
16.9
3.0
4.7
0.9
30
3.3
3.3
0.5
0.5
1999
80
0.0
0.0
0.0
0.0
160
1.3
0.9
0.1
0.1
50
0.0
0.0
0.0
0.0
2000
79
0.0
0.0
0.0
0.0
95
14.7
3.7
3.5
1.0
42
2.4
2.4
0.2
0.2
2001
80
0.0
0.0
0.0
0.0
94
6.4
2.5
0.8
0.3
60
0.0
0.0
0.0
0.0
2002
73
0.0
0.0
0.0
0.0
100
6.0
2.4
1.0
0.4
57
1.8
1.9
0.1
0.1
2003a
80
0.0
0.0
0.0
0.0
100
25.0
4.4
8.8
2.0
60
0.0
0.0
0.0
0.0
2004
110
0.0
0.0
0.0
0.0
132
1.5
1.1
0.2
0.2
58
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

Pool 26
Impounded
Main channel border,
Illinois River
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
27
0.0
0.0
0.0
0.0
47
0.0
0.0
0.0
0.0
1999
80
1.3
1.3
0.1
0.1
50
2.0
2.0
0.1
0.1
2000
39
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2001
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2002
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2003a
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2004
56
0.0
0.0
0.0
0.0
56
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

Pool 26
Main channel border,
Mississippi River
Secondary channel
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
121
0.0
0.0
0.0
0.0
84
0.0
0.0
0.0
0.0
1999
137
0.0
0.0
0.0
0.0
90
0.0
0.0
0.0
0.0
2000
47
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2001
49
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2002
50
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2003a
50
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2004
69
0.0
0.0
0.0
0.0
69
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

La Grange Pool
Contiguous backwater
Isolated backwater
Lakesa
Year
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
n
Frq
±SE
AI
±SE
1998
173
0.0
0.0
0.0
0.0
179
0.0
0.0
0.0
0.0
–
–
–
–
–
1999
190
0.0
0.0
0.0
0.0
188
0.0
0.0
0.0
0.0
–
–
–
–
–
2000
100
0.0
0.0
0.0
0.0
138
0.0
0.0
0.0
0.0
57
80.7
5.3
26.8
3.4
2001
100
0.0
0.0
0.0
0.0
129
0.0
0.0
0.0
0.0
57
77.2
5.6
21.9
2.8
2002
100
0.0
0.0
0.0
0.0
139
0.0
0.0
0.0
0.0
59
79.7
5.3
21.5
2.7
2003b
100
0.0
0.0
0.0
0.0
117
0.0
0.0
0.0
0.0
60
93.3
3.2
45.2
3.5
2004
128
0.0
0.0