Figure 1. Monthly variations in richness in
microcrustacea
Figure 2. Hierarchical cluster analysis of microcrustacea
(2002-03)
Figure 3. Hierarchical cluster analysis of microcrustacea
(2003-04)
Figure 4. Abundance of Copepoda, Cladocera and
microcrustacea (2002-03)
Figure 5. Abundance of Copepoda, Cladocera and microcrustacea (2003-04)
Figure 6. Monthly variations
in species diversity of microcrustacea
Figure 7. Monthly variations in evenness of microcrustacea
Figure 8. Monthly variations in dominance of microcrustacea
Table 1. Abiotic factors of
Loktak Lake
|
|
2002-03 |
2003-04 |
Study period |
|
Parameters |
Mean ± SD |
Mean ± SD |
Mean ± SD |
|
|
|
|
|
|
Water temperature
ºC |
21.4 ± 4.0 |
22.2 ± 4.1 |
21.8 ± 4.2 |
|
Rainfall mm |
112.1 ± 116.8 |
164.4 ± 183.7 |
138.2 ± 154.8 |
|
pH |
6.38 ± 0.23 |
6.25 ± 0.39 |
6.31 ± 0.32 |
|
Specific
conductivity µS/cm |
98.9 ± 19.7 |
87.9 ± 11.1 |
93.3 ± 17.1 |
|
Dissolved O2 mg/l |
6.2 ± 1.1 |
5.3 ± 0.7 |
5.7 ± 1.1 |
|
Free CO2 mg/l |
9.5 ± 2.1 |
8.9 ± 2.0 |
9.2 ± 2.0 |
|
Alkalinity mg/l |
16.0 ± 4.4 |
22.1 ± 8.1 |
19.1 ± 7.1 |
|
Hardness mg/l |
38.1 ± 8.2 |
38.4 ± 7.2 |
38.3 ± 7.8 |
|
Phosphate mg/l |
0.23 ± 0.12 |
0.21 ± 0.04 |
0.22 ± 0.10 |
|
Nitrate mg/l |
0.34 ± 0.04 |
0.30 ± 0.03 |
0.32 ± 0.04 |
|
Sulphate mg/l |
0.86 ± 0.12 |
0.87 ± 0.12 |
0.86 ± 0.12 |
|
Silica mg/l |
10.4 ± 1.2 |
9.7 ± 1.6 |
10.1 ± 1.4 |
|
Chloride mg/l |
14.9 ± 3.1 |
16.6 ± 2.7 |
15.8 ± 3.0 |
|
Dissolved organic
matter mg/l |
1.38 ± 0.40 |
1.29 ± 0.39 |
1.34 ± 0.39 |
|
Total dissolved
solids mg/l |
0.46 ± 0.22 |
0.43 ± 0.17 |
0.44 ± 0.19 |
Table 2. Temporal variations of microcrustacea
|
|
2002-03 |
2003-2004 |
|
|
|
|
|
QUALITATIVE |
|
|
|
Micro-Crustacea 57 species |
26-47 33± 6 |
24-46 32± 6 |
|
Community similarity % |
51.8-87.3 |
54.2-90.9 |
|
Cladocera 51 species |
22-42 29±5 |
20-41 28± 5 |
|
Community similarity % |
51.7-82.3 |
53.6-90.0 |
|
|
|
|
|
QUANTITATIVE |
|
|
|
Zooplankton (n/l) |
204-319 246 ± 35 |
256-314 287 ± 34 |
|
Micro-Crustacea (n/l) |
86-145 112 ± 17 |
108-154 124 ± 13 |
|
Percentage |
39.8-54.7 45.7 ± 4.9 |
36.6-48.0 43.3 ± 3.7 |
|
Species Diversity |
2.305-3.331 2.927±0.334 |
2.615-3.526 2.904±0.246 |
|
Evenness |
0.746-0.983 0.883±0.077 |
0.832-0.999 0.905±0.041 |
|
Dominance |
0.084-0.344 0.187±0.074 |
0.111-0.193 0.155±0.023 |
|
|
|
|
|
Different Groups |
|
|
|
Cladocera (n/l) |
42-108 66 ± 20 |
69-103 79± 9 |
|
Percentage |
32.6-82.4 56.8 ± 14.0 |
51.1-771.7 64.7 ± 7.3 |
|
Species Diversity |
2.518-3.211 2.875± 0.212 |
2.311-0.390 2.769± 0.273 |
|
Dominance |
0.093-0.189 0.137± 0.028 |
0.093-0.189 0.137± 0.028 |
|
Evenness |
0.832-0.985 0.914± 0.043 |
0.816-0.996 0.909± 0.042 |
|
Copepoda (n/l) |
19-87 48 ± 21 |
26-64 44 ± 11 |
|
Percentage |
17.4-67.4 41.3 ± 15.8 |
22.0-47.4 34.9 ± 6.8 |
|
Ostracoda (n/l) |
0-3 1 ± 1 |
0-2 1 ± 1 |
|
Conchostraca (n/l) |
0 -1 |
0-1 |
|
|
|
|
|
Important families |
|
|
|
Cladocera |
|
|
|
Chydoridae (n/l) |
34 ± 11 |
39 ± 7 |
|
Daphniidae (n/l) |
14 ± 6 |
26 ± 5 |
|
Sidiidae (n/l) |
12 ± 4 |
11 ± 3 |
|
|
|
|
|
Copepoda |
|
|
|
Cyclopidae (n/l) |
25 ± 13 |
23 ± 7 |
|
|
|
|
|
Important species |
|
|
|
Cladocera |
|
|
|
Mesocyclops leuckarti (n/l) |
17 ± 11 |
16 ± 8 |
|
Microcyclops hyalinus (n/l) |
8 ± 5 |
7 ± 2 |
|
|
|
|
|
Copepoda |
|
|
|
Chydorus sphaericus (n/l) |
7 ± 5 |
8 ± 2 |
|
Ceriodaphnia cornuta (n/l) |
6 ± 4 |
10 ± 5 |
|
Scapholeberis kingi (n/l) |
6 ± 3 |
8 ± 2 |
Table 3. Percentage similarities of microcrustacea (2002-03)
|
Months |
Nov |
Dec |
Jan |
Feb |
March |
April |
May |
June |
July |
Aug |
Sept |
Oct |
|
Nov |
- |
87.3 |
79.4 |
67.7 |
70.2 |
71.0 |
71.4 |
77.2 |
80.0 |
76.2 |
82.5 |
81.8 |
|
Dec |
|
- |
81.7 |
70.8 |
70.0 |
76.9 |
71.2 |
73.3 |
69.8 |
76.7 |
78.8 |
84.1 |
|
Jan |
|
|
- |
80.6 |
70.2 |
67.7 |
67.9 |
67.7 |
70.0 |
82.5 |
76.2 |
78.8 |
|
Feb |
|
|
|
- |
74.5 |
64.3 |
64.0 |
72.7 |
70.4 |
77.2 |
73.7 |
66.7 |
|
March |
|
|
|
|
- |
70.6 |
71.1 |
65.2 |
57.1 |
69.2 |
73.1 |
80.0 |
|
April |
|
|
|
|
|
- |
76.0 |
66.7 |
51.8 |
66.7 |
77.2 |
76.7 |
|
May |
|
|
|
|
|
|
- |
75.6 |
58.3 |
66.7 |
70.6 |
74.1 |
|
June |
|
|
|
|
|
|
|
- |
69.4 |
65.4 |
69.2 |
76.4 |
|
July |
|
|
|
|
|
|
|
|
- |
69.1 |
69.1 |
62.1 |
|
Aug |
|
|
|
|
|
|
|
|
|
- |
75.9 |
72.1 |
|
Sept |
|
|
|
|
|
|
|
|
|
|
- |
78.7 |
|
Oct |
|
|
|
|
|
|
|
|
|
|
|
- |
Table 4. Percentage similarities of microcrustacea (2003-04)
|
Months |
Nov |
Dec |
Jan |
Feb |
March |
April |
May |
June |
July |
Aug |
Sept |
Oct |
|
Nov |
- |
59.4 |
59.6 |
62.1 |
66.7 |
63.5 |
65.6 |
58.0 |
55.2 |
56.1 |
67.7 |
79.4 |
|
Dec |
|
- |
65.3 |
56.0 |
61.5 |
65.4 |
82.1 |
74.1 |
68.0 |
65.3 |
74.1 |
63.3 |
|
Jan |
|
|
- |
79.1 |
57.8 |
54.2 |
65.3 |
72.3 |
69.8 |
76.2 |
76.6 |
67.9 |
|
Feb |
|
|
|
- |
69.6 |
61.2 |
56.0 |
66.7 |
73.8 |
72.7 |
75.0 |
74.1 |
|
March |
|
|
|
|
- |
90.2 |
96.9 |
64.0 |
73.9 |
75.5 |
80.0 |
82.1 |
|
April |
|
|
|
|
|
- |
83.6 |
67.9 |
73.5 |
75.0 |
79.2 |
81.4 |
|
May |
|
|
|
|
|
|
- |
74.1 |
72.0 |
69.4 |
81.5 |
76.7 |
|
June |
|
|
|
|
|
|
|
- |
79.2 |
68.1 |
73.1 |
65.5 |
|
July |
|
|
|
|
|
|
|
|
- |
83.7 |
79.2 |
70.4 |
|
Aug |
|
|
|
|
|
|
|
|
|
- |
89.4 |
75.5 |
|
Sept |
|
|
|
|
|
|
|
|
|
|
- |
79.3 |
|
Oct |
|
|
|
|
|
|
|
|
|
|
|
- |