Nigeria: pelagic primary production in Kainji Lake

LAKE LEVEL, VOLUME AND AREA

Level (m asl)	Volume (km³)	Area (km²)
141.7	15.2	1260
140.2	13.3	1160
138.7	11.5	1075
137.2	9.8	1000
135.6	8.5	920
134.1	7.2	830
132.6	6.0	755
131.1	4.9	680
129.5	3.95	600
128.0	3.1	520
126.5	2.3	440
125.0	1.8	370
123.4	1.3	280
121.9	1.0	210

Table 2

DAM CONSTRUCTION

	m asl
Crest elevation	145.0
Emergency spillway	143.4
Normal max. level	141.7
Normal min. level	131.1
Min. water level	129.0
Spillways	126.5
Turbine intakes	100.6
Normal max. tailwater	106.8

Table 3

SOME PHOTOSYNTHETIC CHARACTERISTICS OF THE MEASUREMENTS

Date	Station Σ P (mg O₂/m²/d)	P max. (mg O₂/m³)	Transp. (m)	V/O	Duration	ε
6. 1.71	D 2050	725	1.2	0.59	4 h 10'
26. 1.	9 2217	638	1.2	O.48	4 h 5'	1.07
27. 1.	14 3160	1500	1.3	0.47	8 h	1.23
28. 1.	15 2517	625	1.4	O.41	3 h 50'	1.25
9. 3.	9 2933	738	1.5	0.42	4 h	1.10
10. 3.	14 1600	413	1.7	0.43	4 h	0.86
11. 3.	15 1233	740	1.9	O.47	4 h	0.84
20. 4.	11 3900	1225	1.0	O.52	4 h 5'	1.35
21. 4.	14 2200	375	2.5	0.28	4 h	0.51
22. 4.	15 2883	588	2.5	0.34	4 h 8'	0.34
29. 4.	D 2317	450	3.7	0.30	4 h 20'
19. 5.	D 3153	463	4.5	0.23	4 h 20'
7. 7.	11 2458	888	0.6	0.60	4 h	1.23
8. 7.	14 2493	713	1.0	0.48	4 h	1.43
9. 7.	6 3938	975	1.6	0.41	4 h	1.08
13. 7.	D 4563	950	1.9	0.34	4 h 8'
18. 8.	11 458	250	0.1	0.91	4 h
19. 8.	14 1675	888	0.35	O.92	3 h 50'	3.51
20. 8.	6 1940	900	0.4	0.77	4 h	2.51
26. 8.	D 1563	575	0.8	0.61	4 h	1.53
28. 9.	11 1713	966	0.25	0.94	4 h	3.24
29. 9.	14 1217	697	0.25	0.95	4 h	3.66
30. 9.	6 888	275	0.25	0.91	2 h
4.10.	D 640	378	0.3	0.97	4 h	2.63
27.10.	11 1313	659	0.35	O.84	4 h	3.17
28.10	14 1125	613	0.4	0.91	4 h	3.10
29.10.	6 3140	1679	0.3	0.90	4 h	3.81
2.11.	D 1443	781	0.4	0.83	4 h 20'	3.07
1.12.	11 2953	1478	0.5	0.83	4 h	2.75
2.12.	14 963	416	0.6	O.72	4 h	2.14
3.12.	6 1385	666	0.6	0.80	4 h	2.08
15.12.	D 432	138	0.6	0.53	4 h	2.30
12. 1.	11 1402	453	1.0	O.54	4 h	1.55
13. 1.	14 948	356	1.0	0.63	4 h	1.95
14. 1.	6 1897	694	0.9	0.61	4 h	1.80
17. 1.	D 1245	578	0.7	0.72	4 h	2.27
16. 2.	11 2000	681	0.9	O.57	4 h	1.72
17. 2.	14 2355	563	1.2	0.40	4 h	1.35
18. 2.	6 1838	531	1.5	O.48	4 h	1.35
21. 2.	D 2848	663	1.4	0.39	4 h	1.34
15. 3.	11 2750	725	1.6	0.44	4 h	1.09
16. 3	14 2635	579	2.0	0.37	4 h
17. 3.	6 2725	531	1.9	0.32	4 h	1.00
20. 3.	D 1938	454	2.0	0.39	4 h	1.03
12. 4.	11 4260	1300	1.5	O.52	3 h 53'	1.14
13. 4.	14 4105	788	2.0	0.32	4 h	0.80
14. 4.	6 2177	444	2.4	0.34	4 h	O.69
17. 4.	D 3397	625	2.6	0.30	4 h 8'	O.69
24. 5.	11 4333	1388	1.0	0.53	4 h	1.58
25. 5.	14 3885	963	1.5	O.41	4 h	O.98
26. 5.	6 2313	781	2.0	O.56	4 h	0.84
29. 5.	D 3522	759	3.2	0.36	4 h	O.67
20. 9.	11 527		0.1		4 h
21. 9.	14 833		0.1		4 h
22. 9.	6 222		0.2		3 h 51'

Table 4

WEEKLY DATA FOR SOLAR RADIATION AT PROJECT SITE, MEW BUSSA

Date (1972)	Weekly Total (cal/cm²)	Date (1972)	Weekly Total (cal/cm²)
13. 3.	3499	31. 7.	2975
20. 3.	3492	7. 8.	2547
27. 3.	3850	14. 8.	2547
4. 4.	3510	21. 8.	2290
10. 4.	3870	29. 8.	2782
17. 4.	3603	4. 9.	2996
24. 4.	3429	11. 9.	3124
1. 5.	3277	18. 9.	2846
8. 5.	3277	25. 9.	2761
15. 5.	3274	2.10.	3167
22. 5.	3060	9.10.	2996
29. 5.	2953	16.10.	3274
5. 6.	3296	23.10.	2761
12. 6.	3296	30.10.	3060
19. 6.	3231	8.11.	3259
26. 6.	3231	13.11.	3216
3. 7.	3403
10. 7.	3360
17. 7.	2696
24. 7.	2354

162552 cal/cm²/a

Table 5

EFFICIENCY OF UTILISATION OF SOLAR RADIATION

Date	Station ΣP+ 3.68		cal/cm²	%
15.3.72	11	2750	211	0.47
16.	14	2635	205	0.47
17.	6	2725	221	0.45
20.	D	1938	119	0.59
12.4.	11	4260	250	0.62
13.	14	4150	245	0.61
14.	6	2177	161	0.49
17.	D	3397	234	0.53
24.5.	11	4333	200	0.79
25.	14	3885	217	O.65
26.	6	2313	104	0.81
29.	D	3522	172	0.75
20.9.	11	527	135	0.14
21.	14	833	199	0.15
22.	6	428	199	0.09

Table 6

DATA OF PRIMARY PRODUCTION IN SOME TROPICAL AND SUBTROPICAL LAKES AND PONDS

	Primary production				No. of measurements
Lake	average			range	No. of measurements
Albert	7.1	g O₂/m²/d		2.7 – 12.2	3	¹
Amaravathi Reservoir	5.54	"		1.29 – 19.17	9	²
Bunyoni	4.8	"		-	1	¹
Chad	7.1	"		-	10	³
Edku	6800	kg/ha/a	freshweight	-	-	⁴
Edku	1	g C/m²/d		-	-	⁵
Edward	13.8	"		-	1	¹
Fort Moat Chingleput	21.96	"		12.16 – 27.08	9	²
Fort Moat Vellore a.	25.36	"		15.78 – 46.64	5	²
Fort Moat Vellore b.	29.53	"		9.45 – 54.78	5	²
George	14.0	"		12.3 – 15.7	2	¹
George Kazinga Cha.	15.0	"		-	1	¹
Hydrodrome	2100	kg/ha/a	freshweight	-	-	⁴
Hydrodrome	320	mg C/m²/d		250 – 500	-	⁵
K.C Kulam	23.81	g O₂/m²/d		8.33 – 30.18	9	²
Mariut South	34000	kg/ha/a	freshweight	-	-	⁴
Mariut Muhmarn Bay	64000	"	"	-	-	⁴
Mariut Centre North	110000	"	"	-	-	⁴
Mariut North	215000	"	"	-	-	⁴
Mariut North	-			4.4 – 9.6 g c/m²/d	-	⁵
Mariut	4.481	g C/m²/d		0.01 – 10.57	200	⁶
Mulehe	2.3			-	1	¹
Nasser	4.405	"		3.21 – 5.23	4	⁷
Stanley Reservoir	2.88	g O₂/m²/d		1.07 – 5.99	9	²
Tamarai Kulam	13.07	"		5.98 – 20.02	5	²
Victoria, offshore	7.3	"		4.9 – 11.4	14	¹
Victoria Pilkington Bay	-	"		4.3 – 6.8	2	⁸
Victoria Pilkington Bay	10.6	"		10.2 – 11.0	2	¹
Victoria Grant Bay	8.5	"		6.3 – 10.7	2	¹
Volta	6.8	"		2.1 – 14.0	6	⁹
White Nile Lagoon	4.0	"		-	1	⁸
White Nile Jebel Aulia	4.3	"		2.4 – 6.2	2	⁸

¹	Tailing, 1965	-	measurements	made	1960–61
²	Ganapati-Sreenivasan, 1970	-	"	"	1962–68
³	Lemoalle, 1969	-	"	"	1968
⁴	Vollenweider, 1958	-	"	"	1957–58
⁵	Elster-Vollenweider, 1961	-	"	"	1957–58
⁶	Aleem-Samaan, 1969	-	"	"	1959–62
⁷	Samaan, 1971	-	"	"	1971
⁸	Tailing, 1957	-	"	"	1954–56
⁹	Viner, 1970	-	"	"	1966