C Chl , by 80%. The average C/Chl in both areas increased up to 369–397, but C/N
decreased (5.9–7.4). We assume a large part of the freshly transformed detritus in
SOM composition.
The weighted averages of the SOM components in the photosynthetic water
layer in the northern area decreased by 1.4–1.9 times, and in the western area, by
2.1–2.7 times, compared to those observed during the spring period. C Chl decreased
by 4.5 times. In comparison to the surface water layer, these values decreased by
1.1–1.7 times. The average C/N ratio did not change greatly (6.5–6.7). The C/Chl
ratio did not change either in the northern area in comparison, but, in the western
Table 10.1 Seasonal variability of the concentrations of SOM components and their ratios in the
surface water layer of different NWBS areas
Area
Sezon
С som , μM
N som , μM
С Chl , mg/m
3
C:N
C/Chl
Western Winter
12:8 Æ 7:8
10.0 Æ 3.7
1:63 Æ 1:15
1.27 Æ 0.56
1:83 Æ 1:48
1.42 Æ 1.08
8:4 Æ 1:9
8.2 Æ 2.3
140 Æ 83
137 Æ 47
Spring
71:4 Æ 39
51.7 Æ 46.5
7:93 Æ 5:73
8.8 Æ 8.15
10:31 Æ 7:27
7.2 Æ 4.3
7:7 Æ 1:2
6.6 Æ 0.5
150 Æ 48
138
Summer 28:4 Æ 16
25.2 Æ 20.1
2:84 Æ 3:66
3.83 Æ 3.24
2:2 Æ 2:4
1.59 Æ 1.76
7:4 Æ 2:3
6.7 Æ 1.8
433 Æ 312
590 Æ 448
Autumn 14:2 Æ 9:1
14.5 Æ 10.4
0:92 Æ 0:12
1.0 Æ 0.29
1:47 Æ 0:73
1.69 Æ 1.0
10:5 Æ 0:9
9.7 Æ 2.5
161 Æ 54
134 Æ 47
Northern Winter
10:0 Æ 2:0
9.4 Æ 1.7
1:7 Æ 0:7
1.41 Æ 0.19
2:01 Æ 1:2
1.34 Æ 0.02
7:6 Æ 4:4
7.0 Æ 2.1
99 Æ 28
84 Æ 16
Spring
87:7 Æ 67:6
77.9 Æ 53.9
13:05 Æ 8:94
11.16 Æ 6.7
8:5 Æ 12:1
6.73 Æ 6.25
6:8 Æ 1:6
6.4 Æ 1.0
265 Æ 178
287 Æ 165
Summer 39:2 Æ 29
56.1 Æ 18.5
10:2 Æ 3:23
6.7 Æ 5.12
3:54 Æ 2:2
3.6 Æ 2.26
5:9 Æ 1:2
6.5 Æ 1.5
369 Æ 171
293 Æ 45
Autumn 12:1 Æ 3:4
11.5 Æ 4.1
1:9 Æ 0:64
1.69 Æ 0.43
1:5 Æ 0:45
1.35 Æ 0.24
7:5 Æ 3:6
7.0 Æ 1.8
126 Æ 45
103 Æ 29
Central
Winter
7:6 Æ 2:1
7.1 Æ 2.4
0:98 Æ 0:45
0.86 Æ 0.26
1:07 Æ 0:71
1.0 Æ 0.68
9:17 Æ 3:8
9.0 Æ 1.9
146 Æ 71
126 Æ 33
Spring
15:3 Æ 7:9
12.8 Æ 5.8
2:35 Æ 1:55
1.87 Æ 0.96
0:56 Æ 0:4
0.65 Æ 0.37
7:6 Æ 1:9
6.9 Æ 2.4
396 Æ 264
274 Æ 159
Summer 15:1 Æ 8:4
17.7 Æ 6.4
1:4 Æ 1:33
2.26 Æ 0.82
0:9 Æ 1:2
0.61 Æ 0.45
10:2 Æ 6:5
8.3 Æ 1.8
802 Æ 602
770 Æ 478
Autumn 10:7 Æ 5:8
10.9 Æ 7.2
1:17 Æ 0:58
1.11 Æ 0.55
0:88 Æ 0:56
0.74 Æ 0.55
9:3 Æ 3:3
9.1 Æ 2.5
217 Æ 194
201 Æ 106
Eastern
Winter
8:9 Æ 2:0
10.3 Æ 2.0
1:05 Æ 0:1
1.3 Æ 0.06
0:57 Æ 0:24
0.56 Æ 0.06
8:7 Æ 2:8
8.1 Æ 2.2
173 Æ 48
207 Æ 32
Spring
14:5 Æ 6:9
11.7 Æ 4.4
2:18 Æ 1:02
1.96 Æ 0.76
0:49 Æ 0:28
0.51 Æ 0.24
7:0 Æ 2:2
6.1 Æ 0.8
600 Æ 599
302 Æ 105
Summer 18:9 Æ 7:5
17.8 Æ 8.9
2:85 Æ 1:34
3.38 Æ 1.22
1:1 Æ 0:97
0.86 Æ 0.65
8:9 Æ 3:3
6.7 Æ 2.3
826 Æ 398
475 Æ 167
Autumn 16:4 Æ 6:0
15.1 Æ 5.1
2:37 Æ 1:07
1.88 Æ 0.72
0:73 Æ 0:52
0.72 Æ 0.48
7:7 Æ 2:3
8.5 Æ 1.9
605 Æ 249
494 Æ 217
Note: The numbers above the line indicate the component values in the surface water layer, and the
numbers below the line, the values in the photosynthetic layer
10 Seasonal Changes of Hydrobiological and Bio-Optical Parameters in the. . .
161
decreased (5.9–7.4). We assume a large part of the freshly transformed detritus in
SOM composition.
The weighted averages of the SOM components in the photosynthetic water
layer in the northern area decreased by 1.4–1.9 times, and in the western area, by
2.1–2.7 times, compared to those observed during the spring period. C Chl decreased
by 4.5 times. In comparison to the surface water layer, these values decreased by
1.1–1.7 times. The average C/N ratio did not change greatly (6.5–6.7). The C/Chl
ratio did not change either in the northern area in comparison, but, in the western
Table 10.1 Seasonal variability of the concentrations of SOM components and their ratios in the
surface water layer of different NWBS areas
Area
Sezon
С som , μM
N som , μM
С Chl , mg/m
3
C:N
C/Chl
Western Winter
12:8 Æ 7:8
10.0 Æ 3.7
1:63 Æ 1:15
1.27 Æ 0.56
1:83 Æ 1:48
1.42 Æ 1.08
8:4 Æ 1:9
8.2 Æ 2.3
140 Æ 83
137 Æ 47
Spring
71:4 Æ 39
51.7 Æ 46.5
7:93 Æ 5:73
8.8 Æ 8.15
10:31 Æ 7:27
7.2 Æ 4.3
7:7 Æ 1:2
6.6 Æ 0.5
150 Æ 48
138
Summer 28:4 Æ 16
25.2 Æ 20.1
2:84 Æ 3:66
3.83 Æ 3.24
2:2 Æ 2:4
1.59 Æ 1.76
7:4 Æ 2:3
6.7 Æ 1.8
433 Æ 312
590 Æ 448
Autumn 14:2 Æ 9:1
14.5 Æ 10.4
0:92 Æ 0:12
1.0 Æ 0.29
1:47 Æ 0:73
1.69 Æ 1.0
10:5 Æ 0:9
9.7 Æ 2.5
161 Æ 54
134 Æ 47
Northern Winter
10:0 Æ 2:0
9.4 Æ 1.7
1:7 Æ 0:7
1.41 Æ 0.19
2:01 Æ 1:2
1.34 Æ 0.02
7:6 Æ 4:4
7.0 Æ 2.1
99 Æ 28
84 Æ 16
Spring
87:7 Æ 67:6
77.9 Æ 53.9
13:05 Æ 8:94
11.16 Æ 6.7
8:5 Æ 12:1
6.73 Æ 6.25
6:8 Æ 1:6
6.4 Æ 1.0
265 Æ 178
287 Æ 165
Summer 39:2 Æ 29
56.1 Æ 18.5
10:2 Æ 3:23
6.7 Æ 5.12
3:54 Æ 2:2
3.6 Æ 2.26
5:9 Æ 1:2
6.5 Æ 1.5
369 Æ 171
293 Æ 45
Autumn 12:1 Æ 3:4
11.5 Æ 4.1
1:9 Æ 0:64
1.69 Æ 0.43
1:5 Æ 0:45
1.35 Æ 0.24
7:5 Æ 3:6
7.0 Æ 1.8
126 Æ 45
103 Æ 29
Central
Winter
7:6 Æ 2:1
7.1 Æ 2.4
0:98 Æ 0:45
0.86 Æ 0.26
1:07 Æ 0:71
1.0 Æ 0.68
9:17 Æ 3:8
9.0 Æ 1.9
146 Æ 71
126 Æ 33
Spring
15:3 Æ 7:9
12.8 Æ 5.8
2:35 Æ 1:55
1.87 Æ 0.96
0:56 Æ 0:4
0.65 Æ 0.37
7:6 Æ 1:9
6.9 Æ 2.4
396 Æ 264
274 Æ 159
Summer 15:1 Æ 8:4
17.7 Æ 6.4
1:4 Æ 1:33
2.26 Æ 0.82
0:9 Æ 1:2
0.61 Æ 0.45
10:2 Æ 6:5
8.3 Æ 1.8
802 Æ 602
770 Æ 478
Autumn 10:7 Æ 5:8
10.9 Æ 7.2
1:17 Æ 0:58
1.11 Æ 0.55
0:88 Æ 0:56
0.74 Æ 0.55
9:3 Æ 3:3
9.1 Æ 2.5
217 Æ 194
201 Æ 106
Eastern
Winter
8:9 Æ 2:0
10.3 Æ 2.0
1:05 Æ 0:1
1.3 Æ 0.06
0:57 Æ 0:24
0.56 Æ 0.06
8:7 Æ 2:8
8.1 Æ 2.2
173 Æ 48
207 Æ 32
Spring
14:5 Æ 6:9
11.7 Æ 4.4
2:18 Æ 1:02
1.96 Æ 0.76
0:49 Æ 0:28
0.51 Æ 0.24
7:0 Æ 2:2
6.1 Æ 0.8
600 Æ 599
302 Æ 105
Summer 18:9 Æ 7:5
17.8 Æ 8.9
2:85 Æ 1:34
3.38 Æ 1.22
1:1 Æ 0:97
0.86 Æ 0.65
8:9 Æ 3:3
6.7 Æ 2.3
826 Æ 398
475 Æ 167
Autumn 16:4 Æ 6:0
15.1 Æ 5.1
2:37 Æ 1:07
1.88 Æ 0.72
0:73 Æ 0:52
0.72 Æ 0.48
7:7 Æ 2:3
8.5 Æ 1.9
605 Æ 249
494 Æ 217
Note: The numbers above the line indicate the component values in the surface water layer, and the
numbers below the line, the values in the photosynthetic layer
10 Seasonal Changes of Hydrobiological and Bio-Optical Parameters in the. . .
161