SEAWEED

S 25/1

SMITH, I.R.
The economics of small-scale seaweed production in the South China Sea region.
1987 26 pp
FAO Fish. Circ., no. 806, 1987, 26 pp

This paper reviews available economic data and previous publications on the four major seaweed species cultivated in the South China Sea region. These are the red seaweeds Eucheuma, Gracilaria and Porphyra and, to a much lesser extent, the green seaweed Caulerpa. Available economic data on seaweed farming is very scanty and fails to address key issues with respect to yield and profit variability among farms. Because of these data inadequacies, the future of small farms in the seaweed industry of the South China Sea region remains a matter of conjecture.

S 25/2

DOTY, M.S., CADDY, J.F. and B. SANTELICES (Eds.)
Case studies of seven commercial seaweed resources.
1986 311 pp
FAO Fish. Tech. Pap., no. 281, 1986, 311 pp

Seven case studies are presented on commercial seaweed resources; five on wild crops, respectively Ascophyllum nodosum, Chondrus crispus, Gelidium, Laminaria longicruris and Macrocystis, are provided along with case studies of the farmed crops of Eucheuma and Laminaria japonica. Individually the cases range from descriptions of the wild crops and their management to the managed production of farmed crops including, in several examples, some information on economics and/or processing. These initial seven cases range from those emphasizing but one species from but one part of one country, to studies of a genus as it occurs commercially throughout the world.

S 25/3

DOTY, M.S., CADDY, J.F. and B. SANTELICES (Eds.)
Laminaria mariculture in China.
1986 25 pp
FAO Fish. Tech. Pap., no. 281, 1986, 239–263

Mariculture of Laminaria on artificial floating rafts started in 1952 and commercial production increased steadily until 1980 when the peak production 252,907 tons of the dry product was produced.

S 25/4

DOTY, M.S., CADDY, J.F. and B. SANTELICES (Eds.)
The wild harvest and culture of Laminaria longicruris in Eastern Canada.
1986 45 pp
FAO Fish. Tech. Pap. no. 281. 1986, 193–237

Laminaria longicruris was harvested as a source a alginate through the 1940's. Peak harvests were 5–6000 T/year. Since 1949 the species has been cultured sporadically for human consumption with a peak harvest of 300 tons in 1979. The standing crop is at least 1,000,000 tons with a conservative yield estimate of about 300,000 T/year. Determinants of distribution, abundance and production are well studied for this underutilized species.

S 25/5

DOTY, M.S., CADDY, J.F. and B. SANTELICES (Eds.)
The production and use of Eucheuma.
1986 41 pp
FAO Fish. Tech. Pap., no. 281, 1986, 123–164

Three commercial kinds of Eucheuma are being used for their carrageenans. The three kinds, the annual production of each and their specific carrageenans are respectively: cottonii, 30,000 tons producing kappa carrageenan; spinosum, over 6,000 tons producing iota carrageenan; and gelatinae, about 100 tons producing a mixture of gamma, beta and kappa carrageenans. The principal carrageenan uses are as suspensoid in dairy, luxury human and pet foods and drug products. Over 95% of the annual commercial Eucheuma crop is from farms in the tropical far western Pacific.

S 25/6

GUIST, G.G.Jr., DAWES, C.J. and J.R. CASTLE
Mariculture of the red seaweed Eucheuma isiforme.
1985 2 pp
Pla. Sci., vol. 48, no. 1, 56–58

The growth rate and iota carrageenan content of an ecotype of Eucheuma isiforme found near Bahia Honda Key, Florida and cultivated in outdoor tanks were observed for 7 months during 1975. Cultivated plants fertilized with 34 mu M nitrogen and 3.2 mu M phosphate daily had an average growth rate of 9.8 g salt-free dry matter/m super (2) of lighted surface area of culture tank/day. Unfertilized cultivars averaged 2.9 g SFDM/m super (2)/day. The average iota carageenan content, expressed as percent of salt-free dry seaweed weight, of fertilized unfertilized and wild plants was 53.9%, 56.2% and 61.0%, respectively.

S 25/7

DJAMAL, R., SOSELISA, Y. and S. MARZUKI
Survey on culture location of macroscopic marine algae in the Karimun Jawa Island.
1985 7 pp
J. Pen. Perikanan/J. Mar. Fish. Res., no. 33, 27–34

A survey was carried out in December 1981, of the 26 islands in Karimun Jawa, and 16 could grow seaweeds. Those seaweeds are Eucheuma spinosum with standing crop of 548.5 gr/m super (2), Gracilaria lichenoides 52.7 gr/m super (2), Gracilaria euchemoides 63.4 gr/m super (2) and Gelidium amanisi 0.1 gr/m super (2). Karimun Jawa, Kemujan, Menjangan Besar and Menjangan Kecil Island are suitable for culture experiments.

S 25/8

COTE, G.L. and M.D. HANISAK
Production and properties of native agars from Gracilaria tikvahiae and other red algae.
1986 7 pp
Bot. Mar., vol. 29, no. 4, 359–366

Native agars were extracted from a number of wild and cultured samples of Gracilaria spp., as well as two samples of Terocladia pinnata, and analyzed for gel strength, gelling and melting temperatures, sulfate content, and 3,6-anhydrogalactose content. In addition, the amounts of polysaccharide extracted by hot methanol, cold water, and boiling water were measured. At least four strains of cultured Gracilaria were found to contain native agars worthy of further consideration as commercial sources. It was evident that agar quality and composition can vary, depending not only on the particular strain or species, but also with variations in nutrient levels, light levels, and season.

S 25/9

HODGSON, L.M.
Photosynthesis and pigment content of strain of Gracilaria tikvahiae in continuos outdoor cultivation.
1985 15 pp
J. Phycol., vol. 21, no. suppl., 1985, p 15

Various studies of nutrient dynamics, biomass production, agar, quality etc. have been carried out over the years by the aquaculture groups at Harbor Branch. New mutant forms as well as strains, which have been cultured for years, have been subjected to comparative monitoring of growth carbon-hydrogen-nitrogen ratios, and dry to wet weight ratios. The author discusses measurements of photosynthesis, respiration, chlorophyll a and phycobilin content of these strains, and relate those factors to observed growth rates. Chlorophyll to phycobilin ratios (and, hence, color) were not correlated with photosynthesis or growth.

S 25/10

DEBUSK, T.A., HANISAK, M.D., LAPOINTE, B.E. and J.H. RYTHER
Cultivation of unattached macroalgae in Florida.
1985 15 pp
J. Phycol., vol. 21, no. suppl., 1985, p 15

Research is summarized on the cultivation of sterile populations of Gracilaria tikvahiae, Ulva sp. and Sargassum spp. in outdoor experimental systems under natural environmental conditions. Comparative organic yields are discussed as functions of mixing, water exchange rate, culture density and nutrient enrichment.

S 25/11

LEVINE, H.G. and B.H. BRINKHUIS
Size-specific growth in Laminaria saccharina; a criterion for genetic selection.
1985 11 pp
J. Phycol., vol. 21, no. suppl., 1985, p 11

The authors recorded blade dimensions and elongation rates throughout the annual growth cycle of hundreds of Laminaria saccharina plants cultivated in the field and within greenhouse tanks. Plants encompassing a blade length range of 1–200 cm were used. Normalizing growth rates for blade length has been found to substantially reduce data set variability and provides a solid basis for determining size-specific growth rates. The size-specific growth rate relationship (slope) changes throughout the year, reflecting changes in ambient irradiance, temperature and nutrient conditions. The authors are using these relationships to screen for plants that exhibit higher than average growth rates and atypical morphological characteristics in an effort to examine heritability of these traits.

S 25/12

BIRD, K.T.
Economics of macroalgal production.
1985 7 pp
J. Phycol. vol. 21, no. suppl., 1985, p 7

Calculating and comparing the costs of cultivating marine macroalgae is complicated by a number of factors: location, manpower costs, taxes, stage of commercial development, differing cultivation technologies, and variable algae productivities. Several simple methods are available for calculating production costs: present worth, uniform annual costs, and rate of return. One method, uniform annual costs, is simple although it can lead to higher cost estimates than more complicated financial models. Using the uniform annual cost method, algal production costs are reviewed and compared for site specific technologies: Eucheuma farms, Macrocystis farms, Taiwanese Gracilaria pond culture, Florida Raceway seaweed culture, New York Laminaria farms, and Washington Porphyra cultivation. These costs are then compared on a standardized basis such as a common labor cost/manhour for all technologies.

S 25/13

ANON
Proven technology. Technology of cultured seaweed production.
1983 2 pp
Mar. Fish. Inf. Serv. Tech. Ext. Ser., no. 54, 19–20

Details are given of the culture of seaweeds (Gracilaria edulis) in India, describing the techniques used.

S 25/14

BEAVIS, A., CHARLIER, R.H. and C. DE-MEYER
Laminaria spp. as energy source.
1986 6 pp
Oceans 86. Conf. Rec: Sci-Eng-Adv. vol. 2. Data management, instrumentation & economics, Oceans 86, 1986, 621–626

The basic structural option to accommodate the seaweed plants lay between an offshore or onshore facility. The most promising coastal structure is described. This paper analyzes the commercial maturity of such structures. Two main themes are developed: 1. What are the possible economic and environmental advantages of such a cultivation for a country such as Belgium: 2. Can one draw on research into the extraction of methane gas from such algae using anaerobic digestion? Possibilities for electricity production from biomass are also touched upon. Conclusions are then drawn as to the economic justification of such projects. Are they a viable alternative to traditional beach collection natural seaweed stands?

S 25/15

SHINOHARA, M. and T. SUGIYAMA
Actual production of seedlings of wakame Undaria pinnatifida.
1984 181 pp
Bull. Fish. Exp. Stn. Okayama Prefect. 1983, 1984, 181 p

This paper describes methods developed for the production of Undaria pinnatifida seedlings.

S 25/16

AMANIEU, M., LAUBIER, L. and A. GUILLE (Eds.)
Experimental processes of hybridization in the Laminariales of French coasts.
1985 4 pp
Actes Colloq. INFREMER, no. 1, 15–18

The research has shown that interspecific and intergeneric hybridization is possible in the Laminariales with variable rates according to the species use and these rates were determined precisely only following preliminary study where the rate of parthenogenetic development was evaluated for each particular species. Besides, the results obtained concerning the ecophysiology of the Laminariales and especially the effect of temperature and light on the fertility of the gametophytes, prompt to undertake experimental cultures of the hybrids in order to obtain algae with qualities superior to those of the parents, particularly regarding alginic acid content and growth. The experiments carried out in 1983 concern together the rearing ashore of isolate gametophytes belonging to different species of Laminariales, the realization of crossings in order to obtain hybrid sporophytes, and their transfer into the sea on ropes or nets.

S 25/17

MAIRH, O.P., SOE-HTUN, U. and M. OHNO
Culture of Eucheuma striatum (Rhodophyta, Solieriaceae) in sub-tropical water of Shikoku, Japan.
1986 6 pp
Bot. Mar., vol. 29, no. 2, 185–191

Eucheuma striatum Schmitz was transplanted from the Philippines into the subtropical waters of Tosa Bay, Shikoku Island, Japan. The yearly variation in temperature of the seawater at the culture site was 10.2 to 31.2 degree c, turbidity was 0.1 to 3.7 ppm, and salinity was 31.17 ppt to 33.86 ppt. Plants were grown using a monoline method at a depth of ca 1.0 m below the water surface. Plants could be grown from May to October, when the seawater temperature ranged from 20.9 to 31.2 degree C, with a growth rate of 1.4 to 5.9% day super(-1). The most favourable growth period was from August to October. Maximum biomass production, ca 9100% over the initial weight, was obtained after 5.5 months in October. In the laboratory, plants were grown in artificial seawater made from synthetic sea salt Jamarin U and enriched with a fertilizer (Norimax) under ranges of salinity, temperature, illumination and photoperiod. Maximum growth, as well as fruiting, occurred in culture at 24 degree C, 6 k lux illumination, 12:12 h L/D cycle and culture media of 35.11 ppt salinity.

S 25/18

LIAO, I.C and R. HIRANO (Eds.)
Seaweed aquaculture in Japan. Its present status and future prospects.
1984 117 pp
Proc. of ROC-Japan Symp. Maric., December 14–15, 1981, Taipei, Taiwan, ROC., TML Conf. Proc., no. 1, 1984, 11–128

The total seaweed production in Japan from natural bed and from cultivation was recently estimated to be about 640 thousand tons annually. Among this Konbu (Laminaria), Wakame (Undaria), Nori (including Amanori, (Porphyra), Hitoegusa (Monostroma), Aonori (Enteromorpha) and other edible seaweeds constitute more than 90% of the production. This paper describes in brief the present trend of production and cultivation of seaweeds in Japan and their future prospects.

S 25/19

LIAO, I.C. and R. HIRANO (Eds.)
Seaweed aquaculture and its associated problems in the Republic of China.
1984 10 pp
Proc. of ROC-Japan Symp. Maric., December 14–15, 1981, Taipei, Taiwan, ROC., TML Conf. Proc., no. 1, 1984, 99–109

Two red algal genera, Gracilaria and Porphyra and one species of brown alga, Laminaria japonica are cultivated in the Republic of China. Among them 3 species of Gracilaria, especially G. verrucosa are now extensively cultivated in brackish water ponds in southern parts of Taiwan. The method used in cultivation of Gracilaria in polyculture system, that is, fronds of this alga are freely spread in the pond in which milkfish, Chanos chanos and shrimps or crabs are cultivated. The procedures of cultivation are: a) drying the pond, b) introduction of water, c) seeding and d) introduction of milk fish to control epiphytes. For further development of aquaculture of seaweeds more scientific studies on those economically important marine algae are needed, however, lack of man power in this field may be the most urgent problem to be solved.

S 25/20

WU, C.Y., WEN, Z.C., ZHANG, J.P. and Z.S. PENG
A preliminary comparative study on the productivity of three economic seaweeds.
1984 5 pp
Chin. J. Oceanol. Limnol., vol. 2, no. 1, 97–101

The rates of photosynthesis and respiration of Porphyra, Laminaria and Undaria were determined with an oxygenemeter at different temperatures in an enclosed continuous-flow system. The temperature coefficients of respiration and the net primary productivities for the three species were calculated. The spectacular rates of primary production were found to be as high as 270 g C m super(-2) for P. yezoensis, 2200 g C m super(-2) for L. japonica and 160 g C m super(-2) for U. pinnatifida annually. The low respiratory rates of these three species as well as low light compensation points especially at low temperatures are considered as a reason to save heat energy, resulting in a high productivity, especially in case of Laminaria.

S 25/21

RYTHER, J.H., DEBUSK, T.A. and M. BLAKESLEE
Cultivation and conversion of marine macroalgae.
1984 88 pp
Harbor Branch Foundation, Inc., Fort Pierce, Fl (USA), 1984, 88 pp

Research was conducted on the development of an alternative ocean energy farm concept that would not be dependent upon deep ocean water or other extraneous sources for its nutrient supply and that could be located in shallow, near shore, and protected coastal ocean areas. There are five tasks reported in the document: determination of the annual yield of Ulva in non-intensive cultures; evaluation of the effect of carbon concentration on Gracilaria and Ulva yield; evaluation of spray/mist culture of Ulva and Gracilaria; species screening for the production of petroleum replacement products; and synthesis analysis, and economic energy evaluation of culture data.

S 25/22

LIU, S.J., XIANG, S.G., LIN, B.S. and S.F. ZENG
Study on photosynthesis of Gracilaria. 1. Effect of various light intensity on photosynthesis.
1985 6 pp
J. Fish. China/Shuichan Xuebao., vol. 9, no. 1, 29–35

The relation between light intensity and photosynthesis activity of 4 species of Gracilaria (G. tenuistipitata, G. sp. -Hainan, G. verrucosa, and G. sp. -Haifeng) in Guangdong province, were measured in May and Dec. of 1983 and in Feb. of 1984. In the early summer, the common light compensation point of the species is 1,000 Lux. From Dec. of the second year, the light saturation point of G. verrucosa and G. tenuistipitata is 12,000 Lux and 14,000 Lux respectively. The net photosynthetic rate of Gracilaria was comparatively low in the early summer, but was very high in Dec. and Feb. of second year. The net photosynthetic rate of the sub-branches were higher than that of the main branches. The net photosynthetic rate on the apical part of the sporophyte of G. tenuistipitata was higher than that on the middle and lower parts which show the same rate. The results will provide a scientific basis for cutting and for increasing production technique of Gracilaria. To obtain a good harvest the culturing-raft should be set in the upper layer of seawater during their fast growing period so that the algae can receive strong light to strenthen photosynthesis, and for the algae to grow to the late stage, the raft should be set in the lower layer in order to avoid the strong light and to minimize the adherence of miscellaneous algae.

S 25/23

WAALAND, J.R.
Cloning marine algae for mariculture.
1983 10 pp
J. World Maricult. Soc., vol. 14, 404–414

Traditional marine algal mariculture relies on spores or gametes for inoculation of artificial substrates on which the algae are grown to harvest size in open waters. In the case of Porphyra and Laminaria mariculture, this process has reached a high level of sophistication. Newly established seaweed mariculture industries growing Eucheuma and Gracilaria have employed vegetative propagation techniques successfully in artificial substrate or pond culture of these algae. Methods of fragment production and their inoculation on artificial substrates are described. Early development, transplantation to the field, survival in the field and subsequent growth and longevity are also described. Strain selection and maintenance of genetic stocks of cultivars can be greatly facilitated if spore or gamete reproduction can be bypassed by cloning methods.

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HANSEN, J.E.
A physiological approach to mariculture of red algae.
1983 11 pp
J. World Maricult. Soc., vol 14, 380–391

Initial ecological studies focused on seasonal growth and life history pattern of Gelidium and Gracilaria. The results provided the clues for selection of experimental tolerance ranges for key physical and chemical parameters to be studied. Plant vigor and the algal products of interest were the primary criteria in the strain selection program. The metabolic response patterns for net photosynthesis of the species were then studied to characterize the presumptive environmental optima and tolerance ranges for these red algal cultures. The results from this critical pathway approach were: 1) selected, vigorous strains; 2) basic requirements for cultivation of the species; 3) predictions of how the species will respond in culture; 4) production estimate for use in mariculture feasibility models; and 5) a definition of conditions which must be met by a specific culture technique.

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BRINKHUIS, B.H., BREDA, V.A., TOBIN, S. and B.A. MACLER.
New York marine biomass program. Culture of Laminaria saccharina.
1983 19 pp
J. World Maricult. Soc., vol. 14, 360–379

Preliminary screening studies indicated that Laminaria saccharina L. is a good candidate for growth in seaweed/rope culturing systems. Laminaria sporophytes appear in the field during the spring and late summer. Maximum growth rate (up to 8% multiplied by day super(-1) occurs in the fall and spring. During the winter months, growth continues at 0.5 to 1% multiplied by day super (-1) while temperatures range from -1 to 4 degree C. A rapid increase in growth rate is observed when temperatures approach 6 degree in late March. Growth ceases during the summer months and mature blades erode from distal portions. Much of the field population disappears during the summer months, while plants on raft show greater survival. During the summer months of 1983, a small-scale rope culture farm will be deployed and stocked with young Laminaria sporophytes.

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TSUDA, R.T. and Y.M. CHIANG (Eds.)
Seasonal variation of the quality of agar-agar produced in Taiwan.
1982 15 pp
Proc. of ROC-US Coop. Sci. Sem. on cultivation & utilization of economic algae, 1982, 65–80

This paper describes studies related to variation of the quality of agar-agar produced in Taiwan.