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TEXT 24
LAMINARIA CULTURE IN JAPAN
The kelp, Laminaria japonica, is a temperature coldwater brown alga, naturally dis-
tributed in the northwest coastal areas of the Pacific Ocean. In the late 1920s, several
fronds of kelp were found growing under a pier, in Dalan, Liaoning Province. In the
early 1930 s the Northheast Fishery Company of Japan introduced Laminaria to Da-
lan for experimental culture. However, because of adverse natural conditions technic-
al problems, progress was slow. In the 1940 s, the highest annual output was only 60
odd tones dry weight. Since the founding of the People’s of China, the Government
has placed great emphasis on the development of Laminaria cultivation. Special insti-
tutions were established and systematic research was carried out on Laminaria biolo-
gy, seedling rearing, growout technology and so on. At the same time, investigations
were conducted on environmental conditions in culture waters. By the mid-1950 s,
successful raft culture methods were worked out. In this method, floating rafts are
installed in a suitable culture area and Laminaria seedlings are reared and cultured ar-
tificial substrates.
By 1957, the Laminaria culture area in Shandong and Liaoning Provinces had
reached 235 ha. In the late 1950 s, summer seedling rearing techniques were devel-
oped, in which light intensity, led in a special seedling-rearing room. Compared with
the method of rearing autumn seedling in the sea, the culturing of seedling in the
summer helped extend the growout period by 60 days. This technique not only in-
creased the yield per unit culture area immensely, but also made possible the large
scale culture of Laminaria off the Southern Chinese coast, where the seawater tem-
perature in summer is too high for Laminaria culture. Total culture area exceeded
14.000 ha by late 1980 s and annual production was more than 270.000 tones dry
weight, making China the largest producer of Laminaria in the world. Since 1970s
studies on Laminaria genetics and breeding have brought about many achievements.
Basically, there are two methods of growout for Laminaria. In areas where the sea-
water transparency is good, the vertical or hanging kelp rope culture method is used.
In areas where transparency is poor or the current is strong, the horizontal kelp rope
culture method is adopted. Technical management during the growout period in-
cludes adjustment of water depth and culture density, fertilisser application, repair of
damaged rafts and so on.
Fertiliser application (by splashing; spraying or by using plastic bags or clay
bottle attached to the kelp ropes) is necessary as seawater in many areas of northen
China is nutrient deficient. The main aim of management during growout is to utilise,
adjust and improve natural conditions so as to optimise the growth and development
of Laminaria.
71
TEXT 24
LAMINARIA CULTURE IN JAPAN
The kelp, Laminaria japonica, is a temperature coldwater brown alga, naturally dis-
tributed in the northwest coastal areas of the Pacific Ocean. In the late 1920s, several
fronds of kelp were found growing under a pier, in Dalan, Liaoning Province. In the
early 1930 s the Northheast Fishery Company of Japan introduced Laminaria to Da-
lan for experimental culture. However, because of adverse natural conditions technic-
al problems, progress was slow. In the 1940 s, the highest annual output was only 60
odd tones dry weight. Since the founding of the People’s of China, the Government
has placed great emphasis on the development of Laminaria cultivation. Special insti-
tutions were established and systematic research was carried out on Laminaria biolo-
gy, seedling rearing, growout technology and so on. At the same time, investigations
were conducted on environmental conditions in culture waters. By the mid-1950 s,
successful raft culture methods were worked out. In this method, floating rafts are
installed in a suitable culture area and Laminaria seedlings are reared and cultured ar-
tificial substrates.
By 1957, the Laminaria culture area in Shandong and Liaoning Provinces had
reached 235 ha. In the late 1950 s, summer seedling rearing techniques were devel-
oped, in which light intensity, led in a special seedling-rearing room. Compared with
the method of rearing autumn seedling in the sea, the culturing of seedling in the
summer helped extend the growout period by 60 days. This technique not only in-
creased the yield per unit culture area immensely, but also made possible the large
scale culture of Laminaria off the Southern Chinese coast, where the seawater tem-
perature in summer is too high for Laminaria culture. Total culture area exceeded
14.000 ha by late 1980 s and annual production was more than 270.000 tones dry
weight, making China the largest producer of Laminaria in the world. Since 1970s
studies on Laminaria genetics and breeding have brought about many achievements.
Basically, there are two methods of growout for Laminaria. In areas where the sea-
water transparency is good, the vertical or hanging kelp rope culture method is used.
In areas where transparency is poor or the current is strong, the horizontal kelp rope
culture method is adopted. Technical management during the growout period in-
cludes adjustment of water depth and culture density, fertilisser application, repair of
damaged rafts and so on.
Fertiliser application (by splashing; spraying or by using plastic bags or clay
bottle attached to the kelp ropes) is necessary as seawater in many areas of northen
China is nutrient deficient. The main aim of management during growout is to utilise,
adjust and improve natural conditions so as to optimise the growth and development
of Laminaria.
71
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