354
L. Sifa
Stocking efficiency, e.g. mass weight gain times, expressed as :
K _ gross yield of one species
_
total stocking weight of one species
is shown for the Qingshan reservoir in Table 3. The criteria used to judge
stocking efficienct are : excellent, 10 %; good 5—10 %; less than 10 %, poor.
Table 3.
Stocking efficiency in Qingsham reservoir (Li, 1978)
_______________________________________.__________________…__________________
Stockingï
Yield
.
.
.
S
Year
(No/ha)
(kg/ha)
(kg/ha)
tock1ng eff1c1ency
1972
1
380
33
825
25.0
1973
2
685
63.75
740.25
11.6
1974
2
190
52.50
496.50
9.5
1975
1
425
33.75
605.25
17.6
1976
1
770
42.
565.50
13.5
1977
1
890
45.
646.50
14.4
x bighead and silver carp with a total length of 13.2 cm and weighing an
average of 23.8 g.
CONCLUSION
The problem of reservoir fish culture in China at present are: 35 % of
the suitable culture area is still unused; the yields of reservoir—cultured
fish vary greatly; the yields of most reservoirs cannot be sustained; there
is
a
shortage of fish techniciens and culturists; come new production techni—
ques,
such a cage culture and pen culture, still have to be adapted and
developed for application to reservoirs.
REFERENCES
CHU C., LIN T.,
FANG R.,
1976. On the food habit on erythroculter mongolicus
and
in lake Tung—hu, Wuchang, and the problem.of their
population control. Acta Hydrobiol. Sinica, ], 37—52.
HE Z., LI Y.,
1983.
Studies on the plankton in Qinghe reservoir. Acta
Hydrobiol. Sinica,_1, 71—84.
LI S.,
1980.
The design and the use of barrier net for
fish
escap1ng out of Shanme1 reservoir. Transaction of fishery production
of lakes
and reservoirs, 25, 151—155.
LI Y., 1983. Primary discussion on the ecosystem of fish pond and the role
of Silver carp.
Freshwater fisheries, 3, 8—11.
LIU A.,
1983. The
water
resources
and their exploitation and utilization in
China.
Sc1.Amer., 5, 1—10.
LIU Y-> CHEN $-, 1975: Oxygen consumption of 6 cultural fish fingerlings.
Transaction of fishery production of lakes and reservoirs, 25, 87—94-
L. Sifa
Stocking efficiency, e.g. mass weight gain times, expressed as :
K _ gross yield of one species
_
total stocking weight of one species
is shown for the Qingshan reservoir in Table 3. The criteria used to judge
stocking efficienct are : excellent, 10 %; good 5—10 %; less than 10 %, poor.
Table 3.
Stocking efficiency in Qingsham reservoir (Li, 1978)
_______________________________________.__________________…__________________
Stockingï
Yield
.
.
.
S
Year
(No/ha)
(kg/ha)
(kg/ha)
tock1ng eff1c1ency
1972
1
380
33
825
25.0
1973
2
685
63.75
740.25
11.6
1974
2
190
52.50
496.50
9.5
1975
1
425
33.75
605.25
17.6
1976
1
770
42.
565.50
13.5
1977
1
890
45.
646.50
14.4
x bighead and silver carp with a total length of 13.2 cm and weighing an
average of 23.8 g.
CONCLUSION
The problem of reservoir fish culture in China at present are: 35 % of
the suitable culture area is still unused; the yields of reservoir—cultured
fish vary greatly; the yields of most reservoirs cannot be sustained; there
is
a
shortage of fish techniciens and culturists; come new production techni—
ques,
such a cage culture and pen culture, still have to be adapted and
developed for application to reservoirs.
REFERENCES
CHU C., LIN T.,
FANG R.,
1976. On the food habit on erythroculter mongolicus
and
in lake Tung—hu, Wuchang, and the problem.of their
population control. Acta Hydrobiol. Sinica, ], 37—52.
HE Z., LI Y.,
1983.
Studies on the plankton in Qinghe reservoir. Acta
Hydrobiol. Sinica,_1, 71—84.
LI S.,
1980.
The design and the use of barrier net for
fish
escap1ng out of Shanme1 reservoir. Transaction of fishery production
of lakes
and reservoirs, 25, 151—155.
LI Y., 1983. Primary discussion on the ecosystem of fish pond and the role
of Silver carp.
Freshwater fisheries, 3, 8—11.
LIU A.,
1983. The
water
resources
and their exploitation and utilization in
China.
Sc1.Amer., 5, 1—10.
LIU Y-> CHEN $-, 1975: Oxygen consumption of 6 cultural fish fingerlings.
Transaction of fishery production of lakes and reservoirs, 25, 87—94-