This document discusses seaweed cultivation and utilization. It begins with an introduction to seaweeds, their structure, and the three main types: red, brown, and green algae. It then covers methods for cultivating seaweeds, including site selection, culture preparation using anchors and ropes, and harvesting. The document concludes by outlining various uses of seaweeds as phyco-colloids, food, medicine, agriculture, and industry. It also proposes using seaweed cultivation to help restore damage to the Great Barrier Reef by providing food and nutrients to help balance nitrogen levels.

1. CENTURION UNIVERSITY OF
TECHNOLOGY AND MANAGEMENT
Under Guidance:-
Submitted by:-
Name: mr. BPN
Reg. No.: 001
Year & Sem.: 1st year [ 1st Sem.]
Programme: Botany
Presentation
On
“Seaweeds cultivation and utilization”

2. CONTENTS
1. Introduction
2. Structure
3. Types
4. Cultivation
5. Utilization

3. INTRODUCTION
 Seaweed or benthic marine algae are the group of plants that live either
in marine or brackish water environment.
 Like the land plants seaweed contain photosynthetic pigments and with
the help of sunlight and nutrient present in the sea water, they
photosynthesize and produce food.
 Seaweeds are found in the coastal region between high tide to low tide
and in the sub-tidal region where 0.01% photosynthetic light is
available.
 They occur abundantly along the coasts of Tamilnadu, Gujarat,
Lakshadweep and Andaman- Nicobar islands.
 It belongs to the primitive group of non-flowering, photosynthetic
plants known as thallophyta and thus, have similar ecological roles as
that of other plants.
 Seaweeds - the only source of agar, algin and carrageenan –
Phytochemicals that have wide application in food, confectionary,
pharmaceuticals, dairy and paper industries as gelling, stabilizing and
thickening agents.

4. Cont…
 In India about720 species seaweeds are available, of which 60 are
commercially important.
 The first seaweed that had been, described from the Indian Ocean was a
specimen of Amphiroa (Rhodophyta) collected by Hermann in 1672 .
Linnaeus further recorded Turbinaria turbinate and Sargassum granulatum
from Indian waters.
 High protein content (35.6% in dried nori- Porphyra spp.), high levels of
vitamins A, B, B2, B6, B12, C and biotin.
 Contain higher amounts of important minerals like calcium and iron than
vegetables and fruits
 They are basically classified according to colour into three main group i.e
green(Chlorophyta),brown(Phaeophyta),and red(Rhodophyta).

5.  Seaweeds, especially the brown algae, are generally made up of three
distinctly recognisable parts.
 At the bottom there is a root like structure ,the holdfast, which as the
name implies secure the organism to its habitat.
 It is usually joined by a stipe (stem)to the leaf like blades.They have
one or more blades and have different shapes.In some cases the blade
have a distinct midrib and where, photosynthesis takes place primarily.
 Some species have air-filled bladders, but not all seaweeds share this
structure,consisting only of filaments of cells,which may or may not be
branched. Holdfast:specialized basal structure providing attachment to
a surface,often a rock or another alga.
 The stipe and blade are collectively known as the frond.
structure

6. Fig.1 seaweed Fig.2 Seaweed vs. land plant

7. Types
The main groups of algae cultivated for food are:
• Red algae (Rhodophycea) – e.g. GRACILARIA
• Brown algae (Phaeophyceae)-e.g. FUCUS SERRATUS
• Green algae (Chlorophyceae) – e.g. Enteromorpha
compressa, Monostroma
GRACILARIA FUCUS SERRATUS Enteromorpha compressa

8. Culture preparation-
 1.Prepare the necessary materials such as anchors, soft ties, nylon rope etc.
 2.Seedlings to be planted shall be around 100-200g each.
 3.Careful selection of cuttings is important for successful farming.
Site selection-
 Location, where there is a rapid water turnover.
 Area should be sheltered from very strong wave action,current and winds.
 Tributaries- salinity lower than 30ppt
 Avoid areas that are near the mouth of river or where there is a heavy
freshwater runoff.
 Clear the area of sea-grasses.
 Consider also the availability of labour and materials as well.
CULTIVATION

9. Harvesting-
Two types-1. partial harvesting [Done by pruning the initial seedlings planted to
fill up the allocated planting area after 2-3 weeks period]
2. Total harvesting[Done after 45-60 days culture]
Culture methods-
1.Short stake and line method-
60cm long, short stakes erected on seabed and arranged in a rows.
2.Long stake and long line with float-
1-1.5m long, stakes erected on seabed & arranged wide distance between rows.
3. Bamboo raft-
use bamboo poles as floats and weights as anchors
4.Spider web method-
10-20m, similar to raft method without bamboo
5. Suspended rope and line with rope-
1.5 or more, use ropes suspended by floats and anchored by weights

10. Suspended Rope method

11. Utilization
1. Seaweeds as phyco-colloids-
I. Agar
II. Alginic acid
III. Carrageenan
2. Seaweeds as major food-
I. Nori
II. Kombu
III.Wakam
IV.Salad
3.Seaweeds as medicines
4. In agriculture
5.In papermanufacturing industries
6.Used as energy collectors and potentially useful substances may be
extracted by fermentation and pyrolysis.

13. SEAWEED is a hope for Great Barrier Reef
• One of the largest sea eco system is detoriating day by day due
to marine pollution cause by industries.
• Some of the rarest species population get affected due to coral
reef damage
such as:- 1) Green Sea Turtle
2) Leatherback Turtle
3) Dugong
4) Humpback Whale
If we cultivate seaweed in that place then it has some following
benefits
1) Seaweed is an major source of food for sea turtles & dugong.
2) as a algae it grows upon nitrogen and so can help in balancing
the nitrogen toxicity of the reef area.
3) Creating bushes which can be used by fishes for their living &
etc.

15. References…
1. Wikipidia
2. Research articles{Seaweed resources
in India – current status of diversity
and cultivation: prospects and
challenges (degruyter.com)}