COVER
Culture of Kelp
(Laminaria japonica)
in China



TABLE OF CONTENTS


(RAS/86/024)
Training Manual 89/5

Prepared for the Laminaria Polyculture with Mollusc Training Course conducted by the
Yellow Sea Fisheries Research Institute in Qingdao,
People's Republic of China
(15 June – 31 July 1989)
and organized by the
Regional Seafarming Development and Demonstration Project (RAS/86/024)

June 1989

Training Manual 89/5
(RAS/86/024)

LAMINARIA SEAFARMING
IN CHINA

Prepared by the Yellow Sea Fisheries Research Institute for the
Training and Demonstration Course on Laminaria Seafarming,
conducted on 15 June – 31 July 1989 in Qingdao, People's Republic of China

Organized by the
UNDP/FAO Regional Seafarming Project
RAS/86/024

April 1989

PREFACE

The important commercial seaweed Laminaria japonica was introduced into China in the late 1920s from Hokkaido, Japan. Although commercial production of kelp harvested from its natural habitat has been carried out in Japan for over a century, mariculture of this algae on a very large commercial scale was realized in China in the 1950s. Between the 1950s and the 1980s kelp production in China increased from about 60 to over 250,000 dry weight metric tons annually, making China the largest producer of Laminaria.

The success of the kelp cultivation industry has mainly depended on the adoption of three important techniques: (1) the floating raft method of cultivation in which young sporophytes are attached to culture ropes which are fastened to long floating rafts in suitable coastal waters, (2) low temperature cultivation of summer seedlings in which Laminaria sporelings are cultivated over the summer months in cooled water whose temperature is kept below 10° C, and (c) application of nitrogen fertilizer in the open sea.

The chief extracts from Laminaria are algin, iodine and mannitol, products widely used in textile, printing, medical and food manufacturing industries. Laminaria is also used to manufacture a variety of products for human consumption and for making various kinds of health foods.

The techniques of raft culture and seedling-rearing used for Laminaria production may also be used for cultivating other species of seaweeds, such as Undaria, Gelidium and Eucheuma, as well as for mariculture of scallops, abalone and mussels. Though Laminaria is a cold water species, these growing techniques may be adapted for growing commercial seaweeds in countries located in warmer climates.

This manual was specially prepared for the “Training and Demonstration Course on Laminaria Sefarming,” an activity under the UNDP/FAO/NACA Regional Seafarming Development Project (RAS/86/024). The course will be given at the Yellow Sea Fisheries Research Institute at Qingdao in the summer of 1989. The manual is largely a translation of the book Laminaria Seafarming by Professor Suo Ruying, published in Chinese in May 1988 (Agricultural Press, Beijing). The contents of this manual include the biology and ecology of Laminaria, techniques for seedling rearing, raft culture, harvesting and raw processing methods, control and prevention of disease, and polyculture with other species.

The team of translators included Mr. Wang Zhefu, Mr. Wang Qingyin, Mr. Hua Du, Mrs. Cao Shuli and Mr. Sun Feng. Mr. Wang Yizhong assisted with illustrations.

Final production of the manual which included proofreading, some editing, and printing was done at the NACA Project coordinating unit.

The editors wish to thank leaders at the Yellow Sea Fisheries Research Institute for their generous support of this project. In particular, we wish to thank Mr. Deng Jingyao, Director, and Mr. Yang Conghai, Deputy Director of scientific affairs. Mr. Yang Conghai is also director of the newly established Sino-Canadian Mariculture Research and Training Centre at the Yellow Sea Fisheries Research Institute.

Dr. John Scoggan's work at the Yellow Sea Fisheries Research Institute has been supported by the International Development Research Centre (IDRC), Canada.

Editors

John Scoggan
Zhuang Zhimeng
Wang Feijiu

April 1989

Yellow Sea Fisheries Research Institute
19 Laiyang Road
Qingdao, Shandong Province
People's Republic of China

Notes to the reader

Text format:

The text was composed using a “Word Perfect” word processing programme. Unfortunately, a printer driver programme for the 24-pin printer used to print-out hard copy was lacking. Therefore all superscripts and subscripts are printed in normal letter format. For example, “15 degrees Centigrade” reads “15° C”. The same is true for chemical formulae: CO2, O2, PO4, NO4, NH4, etc. This problem will be corrected in future editions. The editors apologize for any inconvenience to readers.

Use of equivalent terms:

sporeling = seedling
sporeling rope = seedling rope
seedling-rearing station = sporeling-rearing station = seedling station
sporophyte = kelp plant = frond = thallus
spermatangium = antheridium
kelp rope = kelp culture rope
raft rope = floating raft rope = raft

Dimensions:

The Chines “mu”=667 m2
1 ha (hectare)=10,000 m2 = 15 mu
1 acre = approx. 4,000 m2

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.

This electronic document has been scanned using optical character recognition (OCR) software. FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.


TABLE OF CONTENTS

CHAPTER 1: BIOLOGY AND ECOLOGY OF LAMINARIA

1. Range Extension of Laminaria to China

2. Uses of Laminaria

3. Taxonomy of Laminaria

4. Distribution of Laminaria

5. Life History of Laminaria

6. Limiting Effects of Seawater Temperature on Laminaria Growth and Reproduction

7. Morphology of the Sporophyte Plant

8. Anatomy of the Sporophyte Plant

9. Detailed Life History of the Gametophyte Plant

10. Stages of Kelp Culture

11. Culture of Autumn Seedlings

12. Culture of Summer Seedlings

13. Use of Fertilizer

14. Extension of Laminaria Seafarming to Southern China

CHAPTER II: AN INTRODUCTION TO RAFT MARICULTURE METHODS

1. Selecting a Sea Region for Laminaria Culture

2. Classification of Seawater Regions

3. Utilization of Seafarming Regions

4. Main Components of the Basic Floating Raft Unit

5. Types of Rafts Used in Laminaria Seafarming

6. Raft Mariculture Techniques

7. Single Raft - Block - Plantation Unit

8. Management of the Seafarming Plantation Area

CHAPTER III: SPORELING CULTURE OF LAMINARIA

1. Methods Used for Sporeling Culture

2. Construction of the Seedling-rearing Station

3. Cultivation of Parent Laminaria Stock

4. Substrates Used for Collecting Spores

5. Collecting Zoospores

6. Arrangement of Substrates in Sporeling Culture Tanks

7. Management of Factors Affecting Sporeling Culture in Seedling Stations

8. Cleaning Procedures

9. Transfer of Young Sporelings to Intermediate Culture

CHAPTER IV: INTERMEDIATE CULTURE AND TRANSPLANTATION

1. Definition of Terms

2. Intermediate Culture of Young Sporophytes

2.1 Selection of Sea Regions for Intermediate Culture

2.2 Intermediate Culture Methods

2.3 Water Depth Control for Intermediate Culture

2.4 Fertilizer Application

2.5 Preventive Measures: Washing Sporophytes

3. Transplantation of Young Sporophytes

3.1 Materials and Equipment Required for Transplantation

3.2 Timing of Transplantation

3.3 Time Schedule for Transplantation Operations

3.4 Length of Sporophytes for Transplantation

3.5 Transplantation Procedures

CHAPTER V: RAFT CULTURE METHODS USED FOR GROW-OUT

1. Vertical or Hanging Kelp Rope Raft Culture Method

2. Horizontal Kelp Rope Raft Culture Method

3. Mixed Vertical / Horizontal Kelp Rope Raft Culture Method

4. One-Dragon Kelp Rope Raft Culture Method

5. Horizontal Kelp Rope Raft Culture Using Bamboo Pole Floats

6. Horizontal Kelp Rope Raft Culture Using Auxiliary Bamboo Floats

7. Hanging Kelp Rope Culture Using Double Raft Ropes

8. Horizontal Kelp Rope Culture Using Double Raft Ropes

9. Horizontal Kelp Rope Method Without a Floating Raft Rope

CHAPTER VI: MANAGEMENT OF THE GROW-OUT STAGE

1. Management of Cultivation Density

2. Adjusting Water Depth During Grow-out

3. Fertilization Procedures

4. Blade Tip Cutting

CHAPTER VII: HARVESTING AND PROCESSING OF LAMINARIA

1. Harvesting Laminaria

2. When to Harvest: Thickening of the Blades

3. Interval Harvesting Methods

4. Kelp Processing Methods

5. Classifying and Packing of Laminaria

6. Calculating Net Biomass of Kelp Product

CHAPTER VIII: INTEGRATED SEAFARMING - POLYCULTURE

1. Polyculture Systems

2. Hanging Raft Polyculture

3. Hanging / Horizontal Raft Polyculture

4. Mussel and Laminaria Polyculture

5. Integrated Seafarming

6. Selection of a Sea Region for Polyculture

7. Mussel Seedling Preparation

8. Advantages of Polyculture: Increased Output of Higher Quality Products

9. Natural Fertilization in Polyculture

10. Exchange of Gases in Polyculture

11. Plankton Utilization in Polyculture

12. Polyculture of Laminaria and Undaria

13. Polyculture of Scallops and Laminaria

CHAPTER IX: DISEASE PREVENTION AND CONTROL

1. Environmental and Pathogenic Diseases

2. Green Rot Disease

3. White Rot Disease

4. Blister Disease

5. Twisted Blade Disease

6. Malformation Disease

7. Prevention of Sporeling Malformation Disease

8. Sporeling Rot Disease

9. Swollen Stipe / Twisted Frond Disease

10. Disease Associated with Red Tide

CHAPTER X: ARTIFICIAL ENHANCEMENT OF NATURAL LAMINARIA STOCKS

1. Ecological Benefits of Enhancement

2. Commercial Benefits: Low Investment / High Return

3. Conditions Favourable for Laminaria Enhancement

4. Enhancement Methods

4.1 Sinking Stones Covered with Laminaria Spores

4.2 Sinking Parent Laminaria to Produce Spores

5. Submerged Kelp Raft Rope

TABLES

GLOSSARY

FIGURES

SR = cross-indexing to Suo Ruying's book, Laminaria Seafarming (1988)

CHAPTER I:

Fig. 1.1 Range distribution of Laminaria japonica in the Asian Pacific region.

Fig. 1.2 Provinces in northern and southern China where Laminaria seafarming is carried out.

Fig. 1.3 Schematic representation of the life history of Laminaria showing alternation of generations (N--2N).

Fig. 1.4 Terminology used to refer to stages in the life history of Laminaria.

Fig. 1.5 Life history of Laminaria. (SR#9)

Fig. 1.6 Effect of seawater temperature on the formation of sporangial sori. (SR#10)

Fig. 1.7 Monthly seawater temperature ranges at Qingdao in northern China.

Fig. 1.8 Morphology of the Laminaria sporophyte plant. (SR#1)

Fig. 1.9 Transverse section through a sporangial sorus. (SR#4)

Fig. 1.10 Internal anatomy of the Laminaria frond. (SR#3)

Fig. 1.11 Stages of kelp cultivation in northern China.

Fig. 1.12 Seasonal clocks showing timing of the stages of kelp culture in northern China.

Fig. 1.13 Correlation between seawater nutrient levels and area of sporangial sori formed on mature Laminaria blades.(SR#13)

CHAPTER II:

Fig. 2.1 Hanging kelp rope raft culture method.

Fig. 2.2 Horizontal kelp rope raft culture method.

Fig. 2.3 Equipment for anchoring floating raft ropes. (SR#17, SR#18, SR#19)

Fig. 2.4 Single floating rope raft. (SR#14)

Fig. 2.5 Square block of floating rafts. (SR#15)

Fig. 2.6. Outlay of rafts in a seafarming plantation area.

CHAPTER III:

Fig. 3.1 Bamboo rod substrates used for collecting zoospores from naturally growing parent Laminaria beds.

Fig. 3.2 Layout of seedling station culture room.

Fig. 3.3 Water circulation system of the seedling-rearing station.

Fig. 3.4 Rate of formation of sporangial sori on mature Laminaria blades grown at different depths. (SR#12)

Fig. 3.5 Outline of procedures used in southern China for culturing parent Laminaria stock.

Fig. 3.6 Palm rope substrate curtains or mats. (SR#21)

Fig. 3.7 Bamboo culture boards suspended in a culture tank. (SR#22)

Fig. 3.8 Flat plane arrangement of culture mats. (SR#24)

Fig. 3.9 Inclined plane arrangement of culture mats. (SR#25)

CHAPTER IV:

Fig. 4.1 Gripping board used for transplanting. (SR#26)

CHAPTER V:

Fig. 5.1 Vertical or hanging kelp rope raft culture. (SR#27)

Fig. 5.2 Horizontal kelp rope raft culture method. (SR#30)

Fig. 5.3 Mixed vertical / horizontal kelp rope raft culture method. (SR#29)

Fig. 5.4 One-dragon kelp rope raft culture method. (SR#32)

Fig. 5.5 Horizontal kelp rope raft culture using bamboo pole floats. (SR#28)

Fig. 5.6 Horizontal kelp rope raft culture using auxiliary bamboo pole floats. (SR#31)

Fig. 5.7 Double floating/submerged raft unit with hanging kelp culture ropes. (SR#20)

Fig. 5.8 Horizontal kelp rope raft culture using double floating/submerged raft ropes. (SR#33)

Fig. 8.1 Comparison of plankton growth in Laminaria and mussel monoculture and polyculture systems. (SR#35)

Fig. 8.2 Hanging net cage used for growing scallops in a Laminaria and scallop polyculture system.

Fig. 9.1 Effects of varying H2S concentration on zoospores, gametophytes and sporelings. (SR#36)

Fig. 9.2. Characteristic symptoms of the swollen stipe / twisted frond disease. (SR#37)

Fig. 10.1. Hanging Rope Enhancement Method. (SR#38)