INVENTORY ON THE SEAGRASS VEGETATION, ASSOCIATED FAUNA AND FLORAOFSITIO CABU, TAMBLER, GENERAL SANTOS CITY

BY:

BAYBAYON, JOHMAR M.

MAMBALING, DAHLIA F.

OMBANA, MARY GRACE E.

PACOMO, ABEL L.

MARCH, 2014

1. INTRODUCTION

1.1 Rationale

Philippine archipelago has been designated as one of the World’s top 19

biodiversity hotspots, and in fact is in the top five in this elite

group (Philippines’ Biodiversity: A Conservation Imperative, 1992).

Unfortunately, the Philippines is also the world leader in degree of

endangerment, with only 6-8% of natural vegetation remaining and for

less than that in primary condition—leading to the dubious distinction

of generally being considered the hottest of the hotspots and the most

severely endangered of the Mega diversity countries.

Sea grass meadows provide ecosystem services that rank among the

highest of all ecosystems on earth. Sea grass beds have long been

identified as an important habitat for fishes and invertebrates (Orth et

al., 1984). Experimental studies investigating some of the mechanisms

thought to make sea grass a preferred habitat found that food

availability, refuge from predation, increased living space, and habitat

richness were important (Jordan et al., 1996). There are only about 50

species of sea grass in the world and the Philippines has 16 taxa

recorded where Fortes added three new taxa to the list holding a record

of second to Australia which has 17.Sea grasses provide protective

shelter for many animals, including fish, and can also be a direct food

source for manatees and dugongs, turtles, some herbivorous fish and sea

urchins. The roots and rhizomes of sea grasses also stabilize sediments

and prevent erosion while the leaves filter suspended sediments and

nutrients from the water column (Costanza, 1997).

Macro algae play important roles in the ecology of coral reefs.

They are the major food source for a wide variety of herbivores and are

the basis of the reef food-web, they are major reef formers, and they

create habitat for invertebrates and vertebrates of ecological and

economic importance (Costanza, 1997). They also play critical roles in

reef degradation, when abundant corals are often replaced by abundant

macro algae. This may result from over-fishing of herbivorous fish or

from pollution by excess nutrients and sediments. Increased macro algae

on a coral reef are often undesirable, indicating reef degradation,

although this depends on the type of algae (Duarte, 1999).

There is a degrading seagrass and seaweed beds due to human

interventions and their importance to ecosystem is still of issue mainly

due to lack of information. This assessment is done to identify the

species of seagrasses and seaweeds that can be found in the area. Data

in this assessment and inventory is a significant contribution for the

conservation of remaining vegetation.

1.2. Objectives of the study

1.2.1 General Objective

The study aims to assess the species diversity of sea grasses as well as

those associated seaweeds. Also, todetermine its frequency, relative

frequency, density, relative density, dominance and percent cover of sea

grasses beds.

1.2.2 Specific Objective

The study aims to identify and determine the species composition of sea

grasses and its associated fauna and flora. In addition, it also aims to

determine the specific substrates where a specific species thrives as a

result of a zonational pattern.

1.3. Significance of the Study

This assessment is a significant tool for evaluating the ecological

indices of the sea grass vegetation in Sitio Cabu, Barangay Tambler,

Santos City. In addition, it is also significant in determination

of different plants and marine invertebrates that thrive in sea

grasses. This would also serve as a baseline data for future study in

the area. Furthermore, the results can be used as a reference for future

related researches and studies. It could also be used as a tool for a

large scale coastal management.

1.4 Scope and limitation

The assessment would only in the Stio Cabu, Tambler, General Santos

City. It is limited only in assessment of seagrass and the

identification of associated fauna and flora. Furthermore, the

identification of sea grass and seaweeds are up to species level. In

addition, the substrates where the floras are found are recorded in the

slate board.

2. REVIEW OF RELATED LITERATURE

2.1 Seagrass

Seagrasses are not grasses at all. They are flowering plants but they

are not closely related. Close family of seagrass are the lilies. Most

of the species are found in tropical waters. Meadows are especially well

developed in Caribbean coral reefs, where they play an important role in

the stabilization of sediments on less exposed side of the reef.

Seagrass are important, but their role has often been overlooked due

largely to their submerged state. Thayer, Wolfe, and Williams (1975)

state that sea grass bed is more productive than of the cultivated corn.

It also supports a large number of epiphytic organisms, with a total

biomass perhaps approaching that of the sea grass itself. It helps in

active sulfur cycle and initiates sulfate reduction. It also serves as

defense in erosion, thereby preserving the microbial flora of the

sediment and the sediment- water interface. Its leaves the current that

give nutrients within its area. According to den Hartog (1984) sea

grasses are marine angiosperms with a worldwide distribution.

Taxonomically it is quite a small group with only a total of around 60

species. However, their ecological importance is undisputed.

Seagrass ecosystems are one of the main components within the

tropical seascape (Moberg and Rönnbäck 2003) and their presence causes a

dramatic increase in biodiversity of both plants and animals as they act

both as shelter for juvenile animals and as a foraging and nursery area

for many animal species (Larkum et al. 1989, Duarte 2002). Furthermore,

they have a main function as stabilizers of tropical coastal habitats as

they trap nutrients and sediments carried from terrestrial effluents,

protecting coral reefs from turbid waters and beaches from wave erosion.

Sea grass beds also play an important role as indicators of

coastal ecosystem health. Because they are highly sensitive to changes

in environmental, physical, chemical and biological conditions, sea

grass health is used as a sensitive index of the impact of the

activities developed in the area. Short et al. (2007) stated that Sea

grasses represent the dominant component of many shallow marine

habitats. Many sea grass meadows consist only of one sea grass species,

although mixed stands containing up to 14 species may be found in the

tropics, particularly in the Indo-Pacific region which has the highest

sea grass biodiversity on earth. Sea grass meadows are, on an area

basis, very productive ecosystems with an average standing stock sea

grass dry weight of 460 g per m2 and an average growth rate of 5 g dry

weight per m2 per day (Duarte and Chiscano 1999).

2.2 Seaweed

Algae are defined as oxygenic photo synthesizers other than embryophyte

land plants (Cavalier and Smith, 2007). In recent years our knowledge of

these organisms has greatly advanced, thanks to new types of data

(mainly electron microscopy observations and DNA sequence data). Based

on these data, we know now that algae represent an artificial and

unnatural agglomeration of very different organisms, sharing the only

common characteristic of living in aquatic habitats. Algae living in the

sea are typically subdivided in plankton (the complex of microscopic

algae not visible with unaided eye, which live floating in the water)

and benthos (the collectivity of the algae that live attached to the sea

bottom).The seaweeds exhibit an astonishing variety of aesthetic and

diverse life forms throughout the shallow seas of the world. While it is

estimated that there are c. 10,000 species of red, brown and green

seaweed, a great deal more knowledge is needed on how much diversity

exists and where species are distributed. Seaweeds are particularly

useful organisms for studying diversity patterns and planning the

conservation and sustainable use of inshore marine resources, and are

also useful as indicators of climatic change (Van der Strate et al.

2002). They are relatively easy to collect, fixed to the substratum,

often form relatively stable assemblages, and have relatively similar

species numbers in richer temperate and tropical regions. The algae that

form the benthos are plant-like organisms, very diverse and very

different in size, shape and color; they are typically designated with

the term seaweeds. Despite of the undeserved negative connotation

associated with such a name, seaweeds play fundamental role marine

ecosystems, where they have a multitude of beneficial effects. Seaweeds

occur on any shore where a hard bottom or any other types of stable

surfaces are present.

It was reported that seaweeds are an ecologically and economically

important component of marine ecosystems worldwide (Prathep et.al.

2006). They are primary producers and provide shelter, nursery grounds,

and food sources for marine organisms. Around the world they are also

used as foods and fertilizers, as well as for the extraction of valuable

commercial products including cosmetics. Recent research has pointed to

new opportunities, particularly in the field of medicine, associated

with bioactive properties of molecules extracted from seaweeds, using

them as a CO2 sink or even as bio-fuel.

3. MATERIALS AND METHODS

3.1 Study area

Fig.1. Study area: Sitio Cabu, Tambler, General Santos City

3.1.1. General description

The area has sandy and rubbles substrates with outcropping stones

in the area. The area is composed of different species of sea grasses

including Syringodium isoetifolium, Halophila ovalis, Cymodocea serrulata, Cymodocea

rotundata, Halodule pinifolia. The firstseagrass and seaweed vegetations are

approximately 38 meters away from the shoreline as measured from the

highest tide (flotsam).

3.2. Methods

The transect-quadrat technique method (Saito and Atobe, 1970) was used

in assessing sea grass and seaweed. A transect line of 50-meter

fiberglass tape was used to setacross the seagrasses vegetation

perpendicular to the shore at each designated station. The starting

point is at 06.018680 N and 125.139470 E then it ends at 06. 01825 N and

125.13959 E. A four quadrat measuring 50x50cm (0.25 m2) shall be set

along the transect line in each station at10-meter interval. Surface and

bottom temperatures and salinities were determined on each transect. The

number of shoots of every sea grass species was counted on 5

representative grids on each quadrat established on every station. The

number of grids on which each sea grass species was present was also

counted (English et al., 1994).

3.2.1. Materials

The following are important materials used in the assessment with

their specific functions:

Table 1. List of material and their uses

Materials Uses

Transect line measuring the distanceQuadrat Parameter or area for

counting the shoots of sea grass and seaweeds.

slate board recording of data

snorkel and mask Snorkeling

3.3. Data analysis

After the data was gathered, the following computations are going to be

used in order to correlate the data afterwards (English et al., 1994).

a.) Frequency

Total no. of segments in whichSpecies A occurs

f = ---------------------------------------------x 100Total no. of segments sampled

b.) Relative Frequency (RF)

f value of Species ARf= ----------------------------------x 100Total f value of all sp.

c.) Density (Den)

No. of individuals ofSpecies ADen = ------------------------------------------------x 100

Total no. of individuals for all sp.

d.) Relative Density (RDen)

RDen=Density of species Ax100Total Density of all species

e.) Percent cover

Adapted from Saito and Atobe (1970)

4. RESULTS AND DISCUSSION

The following are the data gathered after the assessment. Different

species of seagrass and associated fauna and flora were observed present

on the area of study.

4.1 Result of the Assessment of Sea grass Species Coverage

Species Family Substrates

Halophilaovalis

(Spoon Seagrass)

Hydrocharitaceae Sandy, rubbles

Halophila minor Hydrocharitacea sandy

Cymodoceaserrulata Hydrocharitaceae coarse sand mixed with coraland shell debris

Halodulepinifolia Potamogetonaceae Sandy near the shoreline

Table 2. Sea grass substrates preference

Syringodiumisoetifolium Potamogetonaceae Sandy,muddy,rubbles

Figure 2. Percent Cover of the Sea grass Species of Sitio Cabu, Tambler,General Santos City

Figure 3. Frequency of the Seagrass Species of Sitio Cabu, Tambler,General Santos City

Figure 4. Relative Frequency of Sea grass Species of Sitio Cabu,Tambler, General Santos City

Figure 5. Density of the Seagrass Species of Sitio Cabu, Tambler,General Santos City

Figure 6. Relative density of the Seagrass Species of Sitio Cabu, Tambler, General Santos City

Figure 7. Dominance indices of the Seagrass Species of Sitio Cabu,Tambler, General Santos City

4.2.2 Sea grass Species Compositions of Sitio Cabu, Tambler, GeneralSantosCity

Fig 8. Halophila ovalis (R. Brown, 1858)

Kingdom: PlantaePhylum: TracheophytaSubphylum: EuphyllophytinaInfraphylum: SpermatophytaeSuperclass:  AngiospermaeClass: MonocotsOrder:  AlismatalesFamily: HydrocharitaceaeGenus: Halophila

Halophilaovalis is typically found growing from mid-tidal range to

depths down to 12 meters. Its preferred substrate type is sand and mud

bottoms, but spoon grass has been observed in a variety of substrates

ranging from soft mud to coarse coral rubble. Itsleaves are oblong-

elliptic with rounded tips and occur in pairs. The leaf blades measure

approximately 1-4cm long with lengths sometimes reaching up to 7cm and

0.5-2mm wide. The rhizomes are thin, up to 2mm in diameter, with one or

more roots at each node.

Fig.9.Cymodocea serrulata(Asch. & Magnus)

Kingdom:  PlantaePhylum:  TracheophytaSubphylum:  EuphyllophytinaInfraphylum:  SpermatophytaeSuperclass : AngiospermaeClass : MonocotsOrder:  AlismatalesFamily:  HydrocharitaceaeGenus: Cymodocea

It grows on muddy sand, fine sand or sand with coral

rubble substrates in the intertidal zone. It is a mid-

successional species, and can colonize very quickly once

established. This species can quickly recover or return after a

disturbance.Linear strap-like leaves, 5-9mm wideand serrated leaf

tip.

Fig. 10.Halophila minor (den Hartog, 1985)

Kingdom : PlantaePhylum : TracheophytaSubphylum:  EuphyllophytinaInfraphylum:  SpermatophytaeSuperclass:  AngiospermaeClass: MonocotsOrder:  AlismatalesFamily : HydrocharitaceaeGenus:  Halophila

.This species normally grows on coral sand or muddy sand together

with H. ovalis or with other tropical seagrasses in shallow water. It

also extends into deeper water down to seven m where it forms sparse

patches with other species such as Halodule pinifolia (Kuo et al. 2006).

Fig. 11.Halodulepinifolia (Miki, 1964)Kingdom:  PlantaePhylum:  TracheophytaSubphylum : EuphyllophytinaInfraphylum:  SpermatophytaeSuperclass:  AngiospermaeClass : MonocotsOrder:  AlismatalesFamily:   CymodoceaceaeGenus:  Halodule

This species occurs in the sublittoral zone, typically growing on

sandy or muddy bottoms. It has been observed in both high and low energy

environments, but mostly resides in sheltered bays and pools.

Halodulepinifolia is characterized by long, narrow leaf blades measuring 5-

20cm in length and 0.6-1.2mm in width. The leaf tip is widely rounded

and serrated. The leaf sheaths are approximately 1-4cm long.

Halodulepinifolia has a creeping rhizome with 2-3 roots at each node.

Fig.12Syringodiumisoetifolium (Ascherson, 1939)

Kingdom:  PlantaePhylum:  TracheophytaSubphylum : EuphyllophytinaInfraphylum:  SpermatophytaeSuperclass : AngiospermaeClass: MonocotsOrder:  AlismatalesFamily:  CymodoceaceaeGenus:  Syringodium

Noodle sea grass typically occurs on muddy substrates in depths

down to 6 meters, but has been observed on sandy bottoms in depths down

to 15 meters.Syringodiumisoetifolium can form monospecific meadows; however,

it is usually associated with other seagrasses, including

Cymodocearotundata, Cymodoceaserrulata, Haloduleuninervis and Thalassiahemprichii.

This sea grass has a thin rhizome with 1-3 slightly branched or

unbranched roots at each node. A short stem is also present at each node

bearing 2-3 leaves. Leaf blades are cylindrical approximately 7-30cm

long and 1-22mm wide and narrow towards the base. There is a central

vascular bundle within the leaf blade surrounded by a circle of 6-8 air

channels and 7-15 pericentral vascular bundles.

4.2. Associated Flora

Sitio Cabu, Tambler, General Santos City has also a diverse array of

seaweeds associated with the sea grass bed. It has a sandy substrate on

shallow area with some rocky portion and scattered rubbles.

4.2.1 Seaweeds Species Compositions of Stio Cabu, Tambler, general

Santos City

Fig 13.Acanthophora spicifera (Vahl) Børgesen, 1910

Kingdom: PlantaeDivision: RhodophytaClass:

FlorideophyceaeOrder: CeramialesFamily:RhodomelaceaeGenus: Acanthophora

It has a large, irregularly shaped holdfast for attachment to hard

bottoms. From the holdfast, erect fronds begin to branch out. The main

branches have short, determinate branchlets that are irregularly shaped

and spinose. Branchlets are hook-like, brittle and fragment easily under

heavy wave action. Color is highly variable, and can be shades of red,

purple, or brown (Littler and Littler, 1989).

Fig 14.Bornetella oligospora

Kingdom:  PlantaePhylum:  ChlorophytaClass:  DasycladophyceaeOrder:  DasycladalesFamily: DasycladaceaeGenus:  Bornetella

Thallus bright green, clavate, to 2–4 cm in height, 3–6

mm in diameter. Structure with 24–30 primary laterals per

whorl, each branching into (3–)4(–5) secondary segments that

form a faceted cortex. Each facet with one dichotomously

branched, eventually deciduous, hair.Epilithic in the shallow

subtidal and lower intertidal, often occurring in dense

clusters.

Fig 15. Caulerpasertularioides (J. Agardh,1847)

Kingdom:  PlantaePhylum:  ChlorophytaClass:  UlvophyceaeOrder:  BryopsidalesFamily:  CaulerpaceaeGenus:  Caulerpa

Frond: erect, feather-like, occasionally branched, to 20 cm high,

1-2 cm wide, light green. Branchlets opposite, cylindrical, needle-

shaped, 180-330 µm diam., 3-11 mm long, upcurved or straight; apices

bluntly pointed. Central axes cylindrical, 1.0-1.5 mm diam. Stolons

creeping, extensive, 2.0-2.5 mm diam., to 2 m long, generally shorter;

rhizoids thickly stalked, to 2 mm diam. at stolon, branching to slender

apices.

Fig 16.Halimedaincrassata(J. Ellis, 1816)

Kingdom: PlantaePhylum: ChlorophytaClass:  UlvophyceaeOrder:  BryopsidalesFamily:  HalimedaceaeGenus:  Halimeda

The plants are erect and grow to a height of about 20 to 24 cm.

They have a well-developed, thick, heavily calcified stalk above which

the branches are more or less in one plane. The segments are flat and

usually 3-lobed. They are dull green in the upper portions and whitish

near the base. Most commonly found in shallow sandy areas, including

seagrass beds.

Fig 18. Gracilaria cervicornis (Turner, 1852)

Kingdom: PlantaePhylum: Rhodophyta

Subphylum:  EurhodophytinaClass:  FlorideophyceaeSubclass: RhodymeniophycidaeOrder:  GracilarialesFamily: GracilariaceaeGenus:  Gracilaria

Plants of the largest species can reach 60 cm in length. Thalli

range from erect to prostrate and from terete to broadly flatten. Some

species form articulated fronds composed of cylindrical or irregularly

shaped units..

Fig 19.Halimedaopuntia (Linnaeus, 1816)

Kingdom:  PlantaePhylum: ChlorophytaClass: UlvophyceaeOrder:  BryopsidalesFamily:  HalimedaceaeGenus: Halimeda

They have hick, profusely branched clumps of rounded three-lobed

or ribbed leaf-like segments, between 10 and 25 cm in height. The

branches are numerous and are in different planes, rather than nearly in

a single plane as some other species are. This alga can cover larger

areas with a dense mat so that individual plants are indistinguishable.

They grow in shallow depressions, cracks and crevices, between hard

corals and other somewhat protected areas of the reef, down to 55 m.

Fig 20. Turbinaria ornata (Turner) J. Agardh

Kingdom: PlantaeDivision: PhaeophytaClass: PhaeophyceaeOrder: FucalesGenus: Turbinaria

Found primarily in tropical marine waters. It generally grows on

rocky substrates. In tropical Turbinaria species that are often

preferentially consumed by herbivorous fishes and echinoids, there is a

relatively low level of phenolics and tannins.

Fig. 21 Gracilariaverrucosa (Hudson, 1950)

Kingdom:  PlantaePhylum:  RhodophytaSubphylum:  EurhodophytinaClass:  FlorideophyceaeSubclass:  RhodymeniophycidaeOrder:  GracilarialesFamily:  GracilariaceaeGenus:  Gracilaria

Fig.22 Eucheuma cottonii

Kingdom: PlanrtaePhylum: RhodophytaClass: RhodophyceaeOrder: GigartinalesFamily: SolieriaceaeGenus: Eucheuma

This alga grows to two meters long and is green or yellow in

color. Eucheuma are typically found below the low tide mark to

the upper subtidal zone of a reef, growing on sand to rocky

seafloor areas along a coral reef, where water movement is slow

to moderate.Their growth is similar to terrestrial plant species,

where eucheuma have a growing tip, or apical meristem, which is

also capable of dividing to form new growing branches.

Fig 23. Galaxaura oblongata (J.Ellis & Solander) J.V.Lamouroux, 1816 

Kingdom: PlantaePhylum: RhodophytaClass: FlorideophyceaeOrder: NemalesFamily: GalaxauraceaeGenus: Galaxaura

Red algae that grows on rocks, coral rubbles. Dredged from

rocky substrata at depths of 13 to 18 meter plus another record

at 37 m depth

Fig 24 Gracilaria canaliculata

Kingdom: Plantae Phylum: Rhodophyta Class: Florideophyceae Order: Gracilariales Family: Gracilariaceae Genus: Gracilaria

Thalli are terete, 5-13 cm in height, attached to the substratum

by a large discoid holdfast and by secondary holdfasts formed on

lower portion of branches. Branches are subdichotomously,

unconstricted with obtuse apices. Fresh plants firm in texture

and are light to bright red in color. Surface of the branches are

usually covered with many translucent white spots throughout.

Hair cell is present, borne in clusters visible as white spots on

the frond surface.

4.3 DISCUSSION

Sitio Cabu, Tambler, General Santos City has a sea grass bed with a

sandy substrate with outcropping stone and rubbles. The area is composed

of different seagrass species that seems to have a zonation pattern .It

is composed of two sea grass families, Potamogetonaceae (2 genera, 2

species) and Hydrocharitaceae (3 genera, 3 species). Evidently, sea

grasses are very susceptible to change in physical and chemical

properties of the ocean and with global warming, which is changing the

temperature of the ocean.

As shown on Figure 2, S. isoetifolium (29.45%) has the most highest

percent cover, followed by Halodule pinifolia (25.83%), Cymodocea serrulata

(24.13%) and Halophila ovalis (18.73%) respectively. On the other hand, H.

minor (14.45%) has the lowest percent cover among all species in the

area.

In terms of frequency, Halophila ovalis is the most frequent species

(54.17%), followed by Halodule pinifolia (50%), Cymodocea serulata (37.5%),

Syringodium isoetifolium (33.3%) mand Halophila minor (20%) has the lowest

frequency (see fig 5). Meanwhile, in relative frequency Halophila ovalis is

the most frequent species (27.77%), followed by Halodule pinifolia (27.7%),

Cymodocea serulata (19.22%), Syringodium isoetifolium (17.1%) and Halophila minor

(10.3%) has the lowest realative frequency (see fig 4).

Furthermore, theS. isoetifolium (36.53%) has the highest density among

all the species, followed by H.pinifolia(27.7%),H. ovalis (19.22%)cymodocea

serrulata (15.8%). On the other hand, Halophila minor (0.8%) has the

lowestdensity (See figure 5).

In terms of dominance, Halophila ovalis (74.09%) got the highest dominance among

all species, followed by Halodule pinifolia (64.49%), Syringodium isoetifolium

(52.34%). Halophila minor (20.8%). While, cymodocea serrulata(5.33%) got the

lowest dominance (see figure 7). The area is dominanted by Halophila

ovalisdue to the strong current that was present in the area.

Most seagrasses are limited in their distribution at the

intertidal to the shallow subtidal zone in the marine environment

although a few may be found high in the supratidal zone (spray zone).

The difference in their distributional patterns is reflective of their

ability to adapt to the ambient ecological condition in their habitat.

The presence of a species in a certain habitat is dependent on their

ability to adapt to the synergistic effects of the different ecological

factors in the environment.

In the study area seagrassess thrive at different substrates. Some could

be seen in outcropped stones and rubbles while moist of the species

could be seen in sandy portion. It was observed that sea grass beds

harbor a wide array of flora and fauna. Plant-animal interaction in the

sea grass beds is one of the major areas of expanding near shore

research that emphasize the importance of seagrass in the structuring of

faunal assemblages in the seagrass communities (Nakaoka, 2005). In some

station, sea cucumber juvenile could be seen sheltered in the leaves of

sea grasses especially on species with wide leaves. Other invertebrates

could also be seen in seagrass beds such as hermit crab, polychaete

worm, crinoids, and brittle star. A variety of seaweeds also thrives

with the sea grasses.

5. SUMMARY AND CONCLUSIONS

This chapter includes the summary of findings, conclusions and

recommendations made by the researcher based on the results of the

study.

5.1 Summary

Sitio Cabu, Tambler, General Santos City has a sea grass bed

with a sandy substrate with outcropping stone and rubbles.There are two

seagrass families, viz. Potamogetonaceae (2 genera, 2 species) and

Hydrocharitaceae (3 genera, 3 species) identified in the study area.

Halophila ovalis yields the greatest frequency (54.17%) and relative

frequency (27.77%) and the most dominant species with (74.09%).

Meanwhile, Syringodium isoetifolim is the densest species in the area with

adensity of 36.53% and relative density 19.04%. On the other hand, it

also has the highest percent cover in the area.

The area is of mostly sandy substrates with rubbles teeming with

algae and other marine invertebrates such as juvenile sea cucumber,

hermit crab, polychaete worm, crinoids, and brittle star.

5.2 Conclusion

Based on the data presented the following conclusions were drawn:

The study area is composed of two sea grass families,

Potamogetonaceae (2 genera, 2 species) and Hydrocharitaceae (3

genera, 3 species).

Halophila ovalis yields the greatest frequency and relative frequency,

relative density and the highest percent cover.

Syringodium isoetifolium has the highest percent cover in the area

making it the densest species.

The associated flora (marine algae) in the area is composed of

eight species (5 Rhodphyta, 2 chlorohyta and 1 Phaeophyta).

Halophila ovalis yields the greatest frequency and relative

frequencyand the most dominant species in the area due to the

physical properties of the study area.

The seagrass vegetation of the area is a mixed bed of seagrasses

and is a home for various marine invertebrates as well as the

juvenile fishes and different species of seaweeds.

6. RECOMMENDATIONS

Based on the result of this study the researchers recommended as a

force of action to be taken to have atleast an annual or periodic

assessment of the sea grass and its associated flora and fauna Sitio

Cabu, Tambler, General Santos City. It is for the purpose monitoring the

diversity of the marine flora as well as the faunal assemblages that

thrives in the area.

For further studies, the researchers also recommended an in depth

study on how the physical and chemical parameters of the area affects

the diversity of sea grasses and seaweeds as well as their associated

fauna that thrive in the area. In addition, It was also recommended by

the researchers to extend the assessment to the other coastal area of

the General Santos City.

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7. APPENDICES

Transect 1stations

Species present

No. of grids present

No. of shoot per 1x5 grid per quadrat

Associated fauna

Station 1 Syringodium isoetifolium

Q1=23Q2=22Q3=25Q4=25

59, 35, 38, 45, 4532, 36, 37, 35, 3654, 62, 51, 50, 5759, 58, 70, 68, 64

Hermit crabAlgaePolychaete worm Sea cucumber

Halophila ovalis

Q1=23Q2= 23Q3= 24Q4= 24

27, 19, 29. 22, 1619, 12, 21, 22, 2822, 29, 19, 29, 2117, 29, 26, 25, 27

Cymodocea Q1= 17Q2= 20Q3= 23Q4= 23

13, 24, 35, 13, 1718, 14, 14, 9, 1532, 35, 19, 15, 2318, 18, 38, 35, 32

Halodule Q1=1Q2= 2Q3=9Q4=5

277527

Station 2 Syringodium Q1=14Q2=15Q3= 8Q4= 12

14, 17, 2, 13, 2017, 0, 11, 18, 183, 16, 10, 7,24, 5, 6, 13,

crinoidshermit crabbrittle starhydroids galaxauraturbinaria

10 halimedaHalophila Q1= 13

Q2= 16Q3= 13Q4= 19

21, 17, 12, 17, 1527, 47, 36, 16, 4016, 14, 21, 26, 3234, 25 38, 41, 31

Halodule Q1= 17Q2= 6Q3= 7Q4= 6

69, 46, 46, 21, 225, 7, 3, 6, 08, 10, 11, 0,820, 7, 7, 0, 6

Station 3 Halophila Q1= 0Q2= 0Q3= 0Q4= 3

0003

Halodule Q1= 0Q2= 2Q3= 0Q4= 0

0400

Station 4 Halophila ovalis

Q1= 9Q2= 5Q3= 10Q4= 6

5, 0, 6, 3, 04, 1, 1, 0, 00, 0, 9, 4, 20, 0, 0, 5, 3

Halophila minor

Q1= 4Q2= 7Q3= 0Q4= 10

0,2, 2, 6, 66, 2, 0, 2, 000, 0, 0, 5, 5

Station 5 Halodule Q1= 16Q2= 24Q3= 5Q4= 4

5, 4, 10, 4, 65, 5, 6, 7, 71, 1, 1, 1, 10 ,0, 0, 6, 2

Cymodocea serrulata

Q1= 9Q2= 0Q3= 12Q4= 2

3, 3, 2, 3, 400, 2, 2, 6, 60, 0, 0, 2, 0

GROUP 2SEA GRASS ASSESSMENT38M FROM SHORESTART N 06.018680 E 125.139470END N 06. 01825 E 125.13959STATION 1 0-5 MSTATION 2 10-15 MSTATION 3 25-20 MSTATION 4 30-35 MSTATION 5 45-50 M