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06-bioresourcesstatu.. - M. S. Swaminathan Research Foundation

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Gulf of Kachchh<br />

same coast Spongomorpha indica has been<br />

reported for the first time by Thivy & Visalakhmi<br />

(1963b). The elegant looking Caulerpa<br />

verticillata has been recorded from Okha reef by<br />

Thivy & Visalakhmi (1963a). Thivy & Sreenivasa<br />

Rao (1963) reported the occurrence of<br />

Polysiphonia gopnathensis from the reef at<br />

Gopnath. Chondria armata has been reported<br />

from Port Okha from the lower mid-littoral levels of<br />

Adatra by Thivy & Sreenivasa Rao (1963). A<br />

detailed description of the different species of<br />

Ulva has been given by Krishamurthy & Joshi<br />

(1968). The species of Enteromorpha from India,<br />

many of which one existed in the Gulf of Kachchh,<br />

have been described in detail by Joshi and<br />

Krishnamurthy (1972). An analysis of the seaweed<br />

drift on the Saurashtra coast and its constituents<br />

, have been given by Krishnamurthy (1967). A<br />

survey of the alginate producing seaweeds from<br />

Adatra reef (Okha) has been done by Sreenivasa<br />

Rao et al. (1964).<br />

Murthy et al. (1987) made an ecological study on<br />

the intertidal algae at Okha wherein they have<br />

described the fluctuations in mean monthly<br />

biomass and the environmental factors. According<br />

to them Sargassum is the only genus which was<br />

present in the sampling units throughout the year.<br />

Further, they observed that the contribution of<br />

Chlorophyceae to the total biomass was less as<br />

compared to that by Phaeophyceae or<br />

Rhodophyceae.<br />

There exists a definite contrast between the two<br />

coasts of the Gulf as regards species diversity and<br />

biomass, with luxuriant growth on the southern<br />

shores. The inter-tidal expanse varies from 1-5 kID<br />

with gradual slope and mostly coralline<br />

substratum on the south, very conducive for algal<br />

growth. The MNP area houses 89 species. Species<br />

recorded from a few island were 79 from Bet<br />

Dwarka, 43 from Kalubhar and 40 from Pirotan.<br />

Red algal species (Rhodophycease) dominated<br />

with 39 species, followed by 25 green algae<br />

(Chlorophyceae), 21 brown (Phaeophyceae) and<br />

only 3 blue-green (Cynophyceae)(Sen Gupta et al.,<br />

1999).<br />

The northern shore of the Gulf, on the other hand,<br />

has very poor algal biodiversity. The substratum<br />

being sandy/muddy it does not support algal<br />

growth. Only Enteromorpha (Chlorophyceae) and<br />

some blue-green algae were found in the mangrove<br />

region of Mundra.<br />

8<br />

The supra-littoral zone of the southern shores was<br />

dominated by Ulva sp. Other common algae in this<br />

region were green algae Ernodesmis, Struvea<br />

and Microdictyon and non-articulated coralline<br />

algae-Melobasia(red algae): Brown algae Padina,<br />

Dictyota, Colopomenia, Iyengaria dominated<br />

the mid-littoral zone. Red algae Kjellimania,<br />

Halymenia, Griffisthsia, etc. were dominant in<br />

the lower mid-littoral and sub-tidal zones. Subtidal<br />

region (below 5 meter water depth) was<br />

dominated by Sargassum, Turbinaria and<br />

Kjellimania (Sen Gupta et al., 1999).<br />

c. Sea grass :<br />

Seagrass species exist in the subtidal regions of a<br />

few islands. Two Halophila species exist off<br />

Kalubhar and H. ovalis and Thalassia can be<br />

found off Pirotan. Rich sea grass beds off Kalubhar<br />

islands indicate high prospects of the presence of<br />

the rare and endangered species Dugong dugon,<br />

the sea cow.<br />

d. Mangroves :<br />

The area under mangrove cover along the Gujarat<br />

coast is the second largest in India, next to the<br />

Sunderbans. Of the 1031 km' for State, the Gulf of<br />

Kachchh region with 994 km' mangrove cover<br />

forms 96% of the total. Majority of this mangrove<br />

cover belongs to the Kachchh district,<br />

encompassing an area of 854 kID' (86% of Gulf) of<br />

which over 800 kID'borders the Kori creek (Forest<br />

Statistics, 1998). The coast of Jamnagar and<br />

Rajkot district cover an area of 141 kID' (14%). The<br />

notified mangrove forest ,area is 1324.4 km' for<br />

Kachchh, Jamnagar and Rajkot district together.<br />

Although this region has the maximum mangrove<br />

cover in the State, it displays the low diversity<br />

with only one dominating species Avicennia<br />

marina (Cher) along with mangrove associated<br />

species, like Salvadora per sica, Salicornia<br />

brachaiata, Sueda sp. and Alueropus grass<br />

(Chavan, 1985). On the other hand, Jamnagar<br />

region houses 7 species, e.g. A. marina,<br />

A.officinalis, A.alba, Rhizopora mucronata,<br />

Ceriops tagal and Aegiceras comuculatum<br />

(Singh, 2000, GEER <strong>Foundation</strong> 2002. These<br />

mangroves were having the associate halophytes<br />

as above, (Singh, 2000).<br />

Due to high salinity, grazing and cutting pressure<br />

on the Kachchh mangroves, they have stunted<br />

growth (1-2 m tall). However, trees in some<br />

untouched patches gain a height of 4-5 m on<br />

Pirotan island and 5-10 m in Kori Creek with fairly

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