The document provides information on seaweeds or macroalgae. It discusses their taxonomy, structure, ecology, common genera and uses. Seaweeds are a source of food, hydrocolloids like agar and carrageenan used in food production, and have applications in medicine, fertilizer, and other industrial uses. The Philippines cultivates various seaweed species like Eucheuma and Kappaphycus which are sources of carrageenan, an emulsifier used in food and other industries. Seaweed farming involves selecting a suitable pollution-free site and using culture methods like stakes, suspended ropes, or raft and spider web systems to grow the seaweeds.
2. SEA WEEDS Seaweed is a loose colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae. Seaweeds can also be classified by use (as food, medicine, fertilizer, industrial, etc.). Most people know two general categories of seaweeds: wracks (members of the brown algal order Fucales such as Fucus) and kelps (members of the brown algal order Laminariales such as Laminaria), and some have heard of Carrageen or Irish Moss (a red alga, Chondrus crispus) and Dulse or Dillisk (also a red alga, Palmaria palmata).
3. SEA WEEDS Seaweeds are particularly important ecologically: they dominate the rocky intertidal in most oceans, and in temperate and polar regions cover rock surfaces in the shallow subtidal. Although only penetrating to 8-40 m in most oceans, some are found to depths of 250 m in particularly clear waters
4. SEA WEEDS Taxonomy A seaweed may belong to one of several groups of multicellular algae: the red algae, green algae, and brown algae. As these three groups are not thought to have a common multicellular ancestor, the seaweeds are a paraphyletic group. In addition, some tuft-forming bluegreen algae (Cyanobacteria) are sometimes considered as seaweeds — "seaweed" is a colloquial term and lacks a formal definition.
6. SEA WEEDS Structure Seaweeds' appearance somewhat resembles non-arboreal terrestrial plants. thallus: the algal body lamina: a flattened structure that is somewhat leaf-like sorus: spore cluster on Fucus, air bladders : float-assist organ (on blade) on kelp, floats : float-assist organ (between lamina and stipe) stipe: a stem-like structure, may be absent
7. SEA WEEDS Structure Seaweeds' appearance somewhat resembles non-arboreal terrestrial plants. holdfast: specialized basal structure providing attachment to a surface, often a rock or another alga. haptera: finger-like extensions of holdfast anchoring to benthic substrate The stipe and blade are collectively known as the frond .
9. SEA WEEDS Ecology The ecology of seaweeds is dominated by two specific environmental requirements. These are the presence of seawater (or at least brackish water) and the presence of light sufficient to drive photosynthesis. A very common requirement is also to have a firm point of attachment. As a result, seaweeds are most commonly found in the littoral zone and within that zone more frequently on rocky shores than on sand or shingle. The ecological niches utilised by seaweeds are wide ranging. At the highest level are those that inhabit the zone that is only wetted by the tops of sea spray, the deepest living are those that are attached to the seabed under several meters of water.
10. SEA WEEDS In some parts of the world, the area colonized by littoral seaweeds can extend for several miles away from the shore. The limiting factor in such cases is the availability of sufficient sun-light to support photosynthesis. The deepest living seaweeds are the various kelps. In addition to the familiar seashore seaweeds, a number of species have adapted to a fully planktonic niche and are free-floating, often with the assistance of gas filled sacs. Sargassum is one of the better known examples of this type of seaweed. A number of species have adapted to the specialised environment of tidal rock pools. In this niche seaweeds are able to withstand rapidly changing temperature and salinity and even occasional drying.
11. SEA WEEDS Uses Seaweed has a variety of purposes, for which it is farmed, or foraged from the wild. Food Seaweeds are extensively used as food by coastal people, particularly in East Asia, e.g. Japan, China, Korea, Taiwan, Thailand, and Vietnam, but also in Indonesia, Belize, Peru, the Canadian Maritimes, Scandinavia, Ireland, Wales, Philippines, and Scotland, among other places. Tiwi, Albay residents discovered a new pancit or noodles made from seaweed, which has health benefits. It is rich in calcium and magnesium and the seaweed noodles can be cooked into pancit canton, pancit luglug, spaghetti or carbonara.
12. SEA WEEDS Seaweeds are also harvested or cultivated for the extraction of alginate, agar and carrageenan, gelatinous substances collectively known as hydrocolloids or phycocolloids. Hydrocolloids have attained commercial significance, especially in food production as food additives. The food industry exploits the gelling, water-retention, emulsifying and other physical properties of these hydrocolloids. Agar is used in foods such as confectionery, meats and poultry products, desserts and beverages and moulded foods. Carrageenan is used in preparation of salad dressings and sauces, dietetic foods, and as a preservative in meat and fish products, dairy items and baked goods. Alginates enjoy many of the same uses as carrageenan, but are also used in production of industrial products such as paper coatings, adhesives, dyes, gels, explosives and in processes such as paper sizing, textile printing, hydro-mulching and drilling.
13. SEA WEEDS Medicine In the biomedicine and pharmaceutical industries, alginates are used in wound dressings, and production of dental moulds and have a host of other applications. In microbiology research, agar is extensively used as culture medium. Carrageenans, alginates and agaroses (the latter are prepared from agar by purification), together with other lesser-known macroalgal polysaccharides, also have several important biological activities or applications in biomedicine.
14. SEA WEEDS Seaweed is also a known source of iodine, an element necessary for thyroid function with deficiencies leading to goitre. It has been asserted that seaweeds may have curative properties for tuberculosis, arthritis, colds and influenza, worm infestations and even tumors. [dubious – discuss] A number of research studies have been conducted to investigate these claims and other effects of seaweed on human health
15. SEA WEEDS Other uses Other seaweeds may be used as seaweed fertilizer. Seaweed is currently being researched as a potential source of biofuel in the form of bioethanol. Seaweed is also an ingredient in some toothpaste, cosmetics and paints.
16. SEA WEEDS Phaeophyceae: Brown Algae Examples: Laminaria and Saccharina, Fucus, Sargassum muticum The brown colour of these algae results from the dominance of the xanthophyll pigment fucoxanthin, which masks the other pigments, Chlorophyll a and c (no Chlorophyll b), beta-carotene and other xanthophylls. Food reserves are typically complex polysaccharides, sugars and higher alcohols. The principal carbohydrate reserve is laminaran, and true starch is absent (compare with the green algae). The walls are made of cellulose and alginic acid, a long-chained heteropolysaccharide.
17. SEA WEEDS There are no known unicellular or colonial representatives; the simplest plant form is a branched, filamentous thallus. The kelps are the largest (up to 70 m long) and perhaps the most complex brown algae, and they are the only algae known to have internal tissue differentiation into conducting tissue; there is, however, no true xylem tissue as found in the 'higher' plants. There are about 1800 species of brown algae, and most are marine. In general, brown algae are larger and more species are found in colder waters. Virtually all the biomass worldwide comes from a relatively small number of species in the orders Laminariales and Fucales. The total wholesale value of dried brown algae worldwide collected in the wild or cultivated is less than $100 million dollars.
18. SEA WEEDS Chlorophyta: Green Algae Examples: Chlamydomonas, Spirogyra, Ulva. Characteristics: Green colour from chlorophyll a and b in the same proportions as the 'higher' plants; beta-carotene (a yellow pigment); and various characteristic xanthophylls (yellowish or brownish pigments). Food reserves starch, some fats or oils like higher plants. Some green algae are to be the progenitors of the higher green plants but there is currently some debate on this point.
19. SEA WEEDS Green algae may be unicellular (one cell), multicellular (many cells), colonial (living as a loose aggregation of cells) or Coenocytic (composed of one large cell without cross-walls; the cell may be uninucleate or multinucleate). They have membrane-bound chloroplasts and nuclei. Most green are aquatic and are found commonly in freshwater (mainly Charophytes) and marine habitats (mainly chlorophytes); some are terrestrial, growing on soil, trees, or rocks. Some are symbiotic with fungi giving lichens. Others are symbiotic with animals, e.g. the freshwater coelentrate Hydra has a symbiotic species of Chlorella as does Paramecium bursaria, a protozoan. Chlorella is now grown and sold as a health supplement and Dunaliella is grown as a source of beta-carotene.
20. SEA WEEDS A number of freshwater green algae (charophytes, desmids and Spirogyra) are now included in the Charophyta (charophytes), a phylum of mostly freshwater and terrestrial algae, which are more closely related to the higher plants than the marine green algae belonging to the Chlorophyta (known as chlorophytes).
21. SEA WEEDS Rhodophyta: Red algae Examples: Palmaria, Coralline algae Characteristics: The red colour of these algae results from the pigments phycoerythrin and phycocyanin; this masks the other pigments, Chlorophyll a (no Chlorophyll b), beta-carotene and a number of unique xanthophylls. The main reserves are typically floridean starch, and floridoside; true starch like that of higher plants and green algae is absent. The walls are made of cellulose and agars and carrageenans, both long-chained polysaccharide in widespread commercial use. There are some unicellular representatives of diverse origin; more complex thalli are built up of filaments.
22. SEA WEEDS A very important group of red algae is the coralline algae, which secrete calcium carbonate onto the surface of their cells. Some of these corallines are articulated (right, Corallina, with flexible erect branches; others are crustose. These corallines have been used in bone-replacement therapies. Coralline algae were used in ancient times as vermifuges, thus the binomial Corallina officinalis.
23. SEA WEEDS Seaweeds in the Philippines The Philippines is an archipelago comprising numerous islands and is endowed with a high level of biodiversity which includes aquatic marine plants and animals. Among the aquatic plants which are economically valuable both locally or internationally are the following: Caulerpa, Eucheuma, Gelidiella, Gracilaria, Kappaphycus, Porphyra and Sargassum. With the exception of Gelidiella, Porphyra and Sargassum, the rest are cultivated, however, the cultivation of Kappaphycus is the most expensive.
24. SEA WEEDS The economic importance of seaweeds or algae, lies on its utilization as food, in industry, pharmacy and medicine. Eucheuma is a source of carrageenen, a natural gum used as additive, binder, and emulsifier on food, pharmaceutical, beverage and cosmetic industries. The major products derived from the utilization of seaweeds are: agar, algin or sodium alginate and carrageenan.
25. SEA WEEDS Site Selection Characteristics of sites suitable for culture: *Pollution free environment (domestic, agriculture and industrial waste) *Farm area must be far away from river system or any freshwater tributaries (salinities lower than 30 ppt – parts per thousand, are detrimental to the normal growth and development of the plant) *Moderate water movement or current to ensure significant nutrient supply *Sandy or rocky bottom *Protected coves or bay areas in order to maximize production *Site should not be exposed during low tide
26. SEA WEEDS Site Preparation *Clear the area of seagrasses, seaweeds, large stones and corals, and other obstacles *Remove or kill the sea urchins in the area because they will eat the seaweeds
28. SEA WEEDS Short Stake and Line Method Characteristics: - Uses short stakes (60cm long) erected on seabed and arranged in rows -Seeded line has no floats Advisable for use: -Exposed or very shallow area at spring low tide Advantage: -Structure easy to construct Disadvantages : -Cannot be farmed on rocky seabeds -Supply of stakes getting low -Minimal surface water movement hardly affects the seaweed susceotible to grazing
29. SEA WEEDS Long Stake and Longline with Float Characteristics: -Uses long stakes (1-1.5m long) erected on seabed & arranged wide distance between rows -Uses long seeded lines with floats Advisable for use: -Submerged areas with 0.5-1.5m water depth at spring low tide Advantages : -Good water movement even with light wave action -Seaweed distance from water surface is constant Disadvantages: -Cannot be farmed on rocky seabed -Supply of stakes getting low -Susceptible to grazing
30. SEA WEEDS Suspended Rope and Line with Rope Characteristics: -Uses ropes suspended by floats and anchored by weights -Seeded lines have floats Advisable for use: -Water depth of 1.5m or more at spring low tide Advantages : -Good water movement even with light wave action -Seaweed distance from water surface is constant -Less susceptible to grazing Disadvantages: -Construction of structure is rather complicates
31. SEA WEEDS Bamboo Raft Characteristics: -Uses bamboo poles as floats and weights as anchors -Seeded lines may or may not have floats Advisable for use: -Water depth of 1.0m or more at spring low tide Advantages : -Good water movement even with light wave action -Seaweed distance from water surface is constant -Less susceptible to grazing Disadvantages: -Bamboos are scarse and expensive -Construction of structure is rather complicated
32. SEA WEEDS Raft Method Characteristics: -Uses bamboo poles as floats and iron stakes asanchors -Styrofoam balls to keep seaweeds at desired level Advisable for use: -Water depth of 10-20m -Wide channels and open bodies of water -Moderately strong waves and water current -Common in areas like Zamboanga and Sulu
33. SEA WEEDS Advantages : -Utilize area efficiently and units can be set-up in an orderly manner -Transferable compact production units which gives high yield -Strong and flexible to ride with waves during rough season -Fewer anchorage per meter, environment-friendly Disadvantages: -Capital and labor intensive
34. SEA WEEDS Spider Web Method Characteristics: -Similar to raft method without bamboo Advisable for use: -Open bodies of water with depth of 10-20m -Moderately strong waves and water current -Group of farment or cooperative farming Advantages : -High yield and greater flexibility -No rigid component making it highly resistant -Self-cleaning and environment-friendly Disadvantages: -Capital and labor intensive -Difficult toset-up -Serious hazard to navigation
35. SEA WEEDS Lantay Method Characteristics: -Uses bamboo as frames -Uses nets to cover the whole structure Advisable for use: -For nursery/ holding purposes Advantages : -Transferable and resistant to strong waves Disadvantages: -Capital and labor intensive -Difficult to maintain -Not applicable for commercial production
36. SEA WEEDS Culture Preparation *Prepare the necessary materials such as banca, anchors, soft ties, nylon ropes and then install the needed structures whether stalking or floating method prior to planting. *Source out quality seedlings from the vicinity to ensure easy transport to the farm site and propagules must be protected from direct exposure to sun and rain.Transport containers like Styrofoam box is best recommended although ordinary jute sacks will suffice. *Seedlings must be immersed in seawater upon arrival preferably in the seedling bin
37. SEA WEEDS Culture Preparation *Seedlings or propagules to be planted shall be around 100-200 g each Only young portion of the plant must be selected for planting to ensure faster growth *Careful selection of cuttings is important for successful farming. Choose healthy and strong branches for planting. *These are usually found at the center and near tips of a healthy plant. Use a clean, sharp stainless steel knife for cutting branches to leave a smooth surface.
38. SEA WEEDS General Farm Management *Visit farm daily *Keep plants always clean (mud, rough seaweeds, sargassum, etc.) *Check and prune the “ice-ice” infected portion of the plants *Tighten loose lines and tie-ties (plastic straw) *Repair or replace all broken/damaged materials such as bamboos or monolines *Adjust the monolines if necessary (slow growth, discoloration, etc.)
39. SEA WEEDS Harvesting There are two types of harvesting : Partial Harvesting - Done by pruning the initial seedlings planted to fill-up the allocated planting area after 2-3 weeks period. Harvested after 45-60 days culture for expansion purposes. Total Harvesting - Total harvesting after 45-60 days culture. Initial or total seedlings requirement are left behind for the next crop.
40. SEA WEEDS The most common practice of farmers is to harvest the whole plant, rather than prune the plant. From the harvested plants, the best-looking plants are selected for use as seedlings for the next crop. These may be stored in the seedbed if these cannot be planted immediately. Harvested seaweeds are placed in bamboo baskets in the banca then brought to the farmhouse drying station.
41. SEA WEEDS Marketing Buying and selling of dried seaweeds are mostly done in the farmers’ house. These practices are common in all seaweed growing areas. Cash basis is the mode of payment in the coastal areas. Farm gate price varies depending on the location and variety.
42. SEA WEEDS Post-Harvest Preparation Cleaning - before drying the seaweeds it’s a must to clean thoroughly the materials to ensure good quality product. Cleaning should include removal of all foreign material such as plastic straws, stones, woods, and most important,any sand sticking to the thalli. Sand causes severe problems during carrageenan extraction due to its abrasive properties. Drying - Seaweeds should be dried immediately after harvest, kept clean and not allowed to come in contact with fresh water. Solar drying is the most popular and low cost option, taking 2-3 days under ideal conditions. The wet to dry ratio for Kapphycus or Eucheuma cottonii is about 7:1 kilos.
43. SEA WEEDS Seaweed is an important component of the marine ecosystem along with the mangrove and coral reefs and can be viewed in two perspectives, from its ecological value as well as its economic uses. Seaweed contributed about 27% to the total 2002 fisheries production, with Regions IV, IX and ARMM as major producers. The steady increase in production for the past five (5) years (1997-2002) can be attributed to high market demand, better price and good weather condition that encourage farmers to expand their areas for seaweed culture. The industry employs between 100,000-120,000 manpower where 90% are seaweed farmers and the rest are seaweed processors and traders
44. SEA WEEDS The Philippines is one of the top producers of seaweeds in the world, specifically the red seaweeds - next to China and Japan. Seaweeds are exported either in raw forms (fresh or dried seaweeds) or processed forms (semi-refined chips/carrageenan and refined carrageenan). The major importing countries of seaweeds and its natural products are France, Korea, China, USA and Hong Kong. Despite the continuous increase in seaweed production and share in the world market, the industry is beseeched with existing problems and constraints. To address these problems and constraints, the DA-BFAR will provide strategies and interventions for the next fifteen (15) months which include, among others the, e.g. establishment of additional seaweed nurseries, promotion of seaweed health management, provision of post-harvest facilities and establishment of a pilot semi-processing plant.
45. SEA WEEDS The Philippines is one of the top producers of seaweeds in the world, specifically the red seaweeds - next to China and Japan. Seaweeds are exported either in raw forms (fresh or dried seaweeds) or processed forms (semi-refined chips/carrageenan and refined carrageenan). The major importing countries of seaweeds and its natural products are France, Korea, China, USA and Hong Kong. Despite the continuous increase in seaweed production and share in the world market, the industry is beseeched with existing problems and constraints. To address these problems and constraints, the DA-BFAR will provide strategies and interventions for the next fifteen (15) months which include, among others the, e.g. establishment of additional seaweed nurseries, promotion of seaweed health management, provision of post-harvest facilities and establishment of a pilot semi-processing plant.