COASTAL MARINE ECOSYSTEM

Assessment of Macrobenthic Flora and Fauna in the Intertidal Area at Dalipuga Beach, Iligan City, Philippines

A Scientific Paper Presented to Prof. Karyl Marie F. Dagocof the Department of Biological Sciences

College of Science and MathematicsMSU-Iligan Institute of Technology

Iligan City

In Partial Fulfillment of the Requirements inBio 107.2 – General Ecology Laboratory

Second Semester 2015-2016

Presented byMitchelle Dawn E. Paye

May 19, 2016

ACKNOWLEDGEMENTS

The researcher would like to express her heartfelt gratitude to all the people, who in one

way or another have guide, assisted, and helped her in the success of this scientific paper;

To Professor Karyl Marie Fabricante - Dagoc for the guidance and help in doing the field

sampling.

And above all, to the Almighty Father, for giving His strength, hope, and wisdom all throughout

the process of making this scientific paper.

Mitch

ABSTRACT

Marine ecosystems are a complex of habitats defined by the wide range of physical,

chemical, and geological variations that are found in the sea. Marine ecosystems are important to

humankind both ecologically and economically, providing numerous vital goods and services, and

supporting the processes that sustain the entire biosphere. Unfortunately, in spite of their widely

recognized value, human activities are putting marine ecosystems under pressure. The objectives

of this study is to assess the macrobenthic flora and fauna species to correlate its relative

abundance to the physico-chemical parameters and to determine the ecological indices of the

area. By the use of transect line and quadrat, this study was being conducted. Two quadrats (

1m2) was laid in the transect line. One quadrat was placed in the 2-meters and the other one is in

the 6-meters transect line. The species found were collected for identification. The physico-

chemical parameters were measured with two repeated trials using a thermometer for the water

and soil temperature,slingshot psychrometer for humidity, and pH paper for the pH. Sediment

grain size analysis was conducted. Water and soil temperature was found to be 26°C -27°C and

25°C -26°C, respectively. Humidity is 26%, it was sand and gravel, and the water has a pH of 7

and 8. Salinity is 31 part per thousand. Thus, it was normal. Results in microbenthic flora show

that only one species of algae was found in the area (Phaeophyta) and seagrass were also

found. Macrobenthic fauna was absent. Ecological indices acquired an unsatisfying result due to

the limitation of data.

INTRODUCTION

Zisenis, M. (2010) defines marine ecosystems as a complex of habitats with wide range

of physical, chemical, and geological variations that are found in the sea. Habitats range from

highly productive near-shore regions to the deep sea floor inhabited only by highly specialized

organismsThe marine ecosystem is the largest ecosystem after the whole of Planet Earth

because water accounts for more than 70 % of Earth’s surface.  The marine environment, our

oceans and seas, account for more than 97 % of that. The marine ecosystem, in addition to the

temperate and tropical oceans, includes the shorelines, with mud flats, rocky and sandy shores,

tide pools, barrier islands, estuaries, salt marshes, and mangrove forests making up the shoreline

segment. It also includes intertidal zones, lagoons, coral reefs, the deep sea, and the sea floor.

They can be contrasted with freshwater considered ecosystems because it supports a great

diversity of life and variety of habitats.

Coastal ecosystems are areas where land and water join to create an environment with a

distinct structure, diversity, and flow of energy. They are home to many different types of plants

and animals.

However, coastal ecosystems are also very sensitive to changes in the environment, and

there is concern that some areas are now struggling to maintain their diversity due to human

activity, the introduction of non-native species, and other factors. In addition, Cinches, V. (2013)

conclude that destructive fishing activities such as dynamite and cyanide fishing, muro-ami,

bottom trawling and overfishing are depleting our sea’s resources without giving it time to recover.

Marine life is also being threatened by climate change which causes coral bleaching and

acidification.it also encounters pollution and eutrophication.

According to Kingsford, M. (2016), marine organisms are not distributed evenly

throughout the oceans. Variations in characteristics of the marine environment create different

habitats and influence what types of organisms will inhabit them. The availability of light, water

depth, proximity to land, and topographic complexity all affect marine habitats.

The availability of light affects which organisms can inhabit a certain area of a marine

ecosystem. The greater the depth of the water, the less light can penetrate until below a certain

depth there is no light whatsoever. The physical and chemical properties of seawater vary

according to latitude, depth, nearness to land, and input of fresh water. Approximately 3.5 percent

of seawater is composed of dissolved compounds, while the other 96.5 percent is pure water.

The chemical composition of seawater reflects such processes as erosion of rock and sediments,

volcanic activity, gas exchange with the atmosphere, the metabolic and breakdown products of

organisms, and rain (Kingsford, M. 2016).

Using plot and transect sampling, the composition and relative abundance of

macrobenthic flora and fauna will be determined. Williams C.B. (1950) stresses that the relation

between the distributions of species and individuals in the original population and in a series of

quadrats depends on three variables which are the sizes of quadrat, number of quadrats and

richness of flora. Through the use also of some instruments such as thermometer and

refractometer, the physico-chemical paramaters will be measured.

The aim of this study is to determine the composition and relative abundance of

macrobenthic flora (red, green, brown algae and seagrass), determine the sediment type in each

sampling area, correlation between relative abundance of the flora and fauna to the physico-

chemical parameters and ecological indices (Index of dominance, similarity, evenness, and

diversity).

MATERIALS AND METHODS

The field study was conducted at Dalipuga beach, Iligan City for coastal marine ecosystem

sampling on April 15, 2016. The weather condition was good.

Figure 1.a. Location of the sampling site, Dalipuga, Iligan City

Figure 1.b. View of the sampling site, Dalipuga beach, Iligan City, Philippines

I. Installation of the transect line and quadrat

The transect line was laid perpendicular to the shoreline with one end fixed the peg and

the other end tied to the coralline rocks in the subtidal area near the ledge. The transect line is a

rope which was 10 meters calibrated at 1 meter- interval.

The quadrat is 1m2 made of small square nylon. The quadrat is divided equally by 10

continuous bars horizontally and vertically.

II. Assessment proper

A. Macrobenthic algae and seagrass

Two quadrats (1m2) was laid in the transect line. The transect line was laid and was

selected randomly. One quadrat was placed in the 2-meters and the other one is in the 6-meters

transect line. The number of squares with a particular algal group (red, green, or brown) were

counted. The same procedure was conducted for the seagrass. Some photos were taken for

documentation. It was then recorded to the data notebook. The representative samples for every

species were collected and put in a close container with adequate seawater to immerse the

specimen.

B. Determination of Physico-chemical parameters

A thermometer was used in measuring the soil and water temperature. For the

temperature of soil, the bulb of the thermometer was placed 5cm from the soil surface. For the

water temperature, the bulb of the thermometer was touched in the water and read its

temperature. Three trials were conducted.

In identifying its humidity, slingshot psychrometer was used. It is composed of two

thermometers, the wet and dry bulb. The cloth wrapped around the wet bulb was moisten with

water. It was then rotated in the air for two minutes. A conversion table is used to determine the

relative humidity based on temperature readings.

Whereas in measuring the water pH, dip a pH paper into the water. Just a few seconds

will suffice. It was then compared to pH indicator color chart.

In measuring salinity, handheld refractometer was used. Open the plate near the angled

end of the refractometer. Add a couple drops of the liquid onto the exposed prism. Take the liquid

you wish to measure, and use an eyedropper to pick up a couple drops of it. Carefully close the

plate. Cover the prism again by gently pushing the plate back into position. The parts on a

refractometer may be small and delicate, so try not to apply much force even if they become

slightly stuck. Instead, wiggle the plate back and forth with your finger until it moves smoothly

again. Look through the device to see the salinity reading. 

Sediment Grain Size Analysis was also conducted. A soil sample was collected

(approximately 25o mL) on the coastal environment. The samples were placed in a closed

container. It was then added with water and after putting the cap on, the container was shook.

After five days, the samples were observed and recorded.

The ecological indices were determined by using the PAST software. This includes

dominance, evenness and species diversity. In calculating the Diversity indices using PAST, a

new file was open first then input the corresponding data in the spreadsheet. Next, the area that

was wished to analyzed was then highlighted and the “Diversity indices” under the Diversity menu

was clicked to run the data. The Shannon—Weiner index was used for the diversity. Since

relative abundance cannot be computed using this software, it has to be calculated manually. It

can be computed as:

RA (Pi) = Ni/N x 100%

With Ni, the abundance of the i-th species in the sample, and

SN=∑ Ni

i=1with S as the total number of species in the sample

RESULTS AND DISCUSSIONS

Table 1 shows the macrobenthic flora found in each quadrat. The second quadrat was

entirely covered with macrobenthic flora. Thus, its relative abundance is obviously higher than the

first quadrat.

Table 1. Relative abundance of macrobenthic flora

Quadrat No. No. of Squares Percentage Relative abundance

1 8 8 7.4

2 100 100 92.6

The percentage abundance of a species in second quadrat is much higher relative to the

total numbers of individuals of all species sampled. The relative abundance of species in quadrat

2 is 13th times higher compared to quadrat 1. It is inevitable that in such areas in a community,

there are organisms who dominate. In the first quadrat, only algae were present. In contrast,

seagrass was also found in the second quadrat. This is due to some common factors that can

affect their abundance such as abiotic factors and availability of resources. The distribution of an

organism may depend on the adaptations of the organisms. Also, it depends on the area in which

they are most suitable. The particular combination of influences that determine abundance and

distribution are usually unique.

On the identification of the relative abundance of macrobenthic fauna, table 2 shows the

absence of microbenthic fauna such as fishes,

Table 2. Relative abundance of macrobenthic fauna

Quadrat No. Animal Species Count Relative abundance

1 0 0 0

2 0 0 0

There was no macrobenthic fauna found in the quadrat. Maybe this is due to some

factors. According to Tyrone, T. (2016), one causes of the destruction of ocean habitat is climate

change. Perhaps the most devastating of all habitat-altering agents. As Earth's temperature rises,

it is primarily the oceans that absorb the extra heat. Even small temperature changes can have

far-reaching effects on the life cycles of marine animals from corals to whales.

Table 3 shows the different physico-chemical parameters such as temperature, humidity,

pH and salinity. It was obtained from the area of the two quadrats along with the transect line.

Table 3. Physico- chemical parameters

Quadrat No. Temperature Humidity Sediment type

pH Salinity

Water Soil1 27°C 25°C 26 Sand &

gravel 7 31 ppt

2 26°C 26°C 26 Sand & gravel

8 31 ppt

The water temperature in quadrat 1 and quadrat 2 are 27°C and 26°, respectively. Hoyle

B., & Duncan, L. (2009) explains that the water temperature of tropical oceans typically exceeds

20°C (68°F) and stays relatively constant throughout the year. This is because the Sun lies

almost directly overhead for the entire year in the tropics. Thus, it can be deduced from the data

that the water temperature is normal.

Based on the data, the soil temperature ranges from 25°C-26°C. It indicates a good

weather condition. The humidity is 26 in both quadrat areas. In the study of Villaroza, S.M.(2015),

the humidity is also 26 and she concluded that it is normal. Therefore, our humidity is also

normal.

The sediment type of the sampling site is sand and gravel since it is a coastal marine

ecosystem. The pH level is 7 and 8. Since seawater is salty, it is obvious that its ph level is also 7

just like tha pH of salt which means neutral- not acid nor base. However, it possesses small

measurements of basicity.

The salinity is 31ppt which is low compared to the normal salinity which is 35 ppt. This is

because of several factors that affect the salinity. The most common factor is the relative amount

of evaporation or precipitation in an area. If there is more evaporation than precipitation, then the

salinity increases (since salt is not evaporated into the atmosphere). If there is more precipitation

(rain) than evaporation, then the salinity decreases. Another factor that can change the salinity in

the ocean is due to a very large river emptying into the ocean. The runoff from smallest streams

and rivers is quickly mixed with ocean water by the currents and has little effect on salinity

(Anderson G., 2008).

Although there were two trials being conducted, it is possible that the researcher has

commit some errors in getting the salinity. Nansen, F. (2014) concludes that it is impossible to

decide whether the errors are chiefly due to errors in temperature or in the salinity.

Table 4 shows the summary of the algae and seagrass found in the quadrat.

Quadrat

no.

Chlorophyta Phaeophyta Rhodophyta Seagrass

Count Relative

abundance

Count Relative

abundance

Count Relative

abundance

Count Relative

abundance

1 0 0 8 7.4 0 0 0 0

2 0 0 0 0 0 0 100 92.6

Table 4. Summary table

Based on the table, only the algae group chlorophyta is present. Seagrass was found to

be abundant in the second quadrat. Kennedy J. (2014) explains that there are three

classifications of algae- Chlorophyta, Phaeophyta and Rhodophyta. Brown algae is the largest

type of algae. Brown algae is in the phylum Phaeophyta, which means "dusky plants." Brown

algae is brown or yellow-brown in color and found in temperate or arctic waters. Brown algae

typically have a root-like structure called a "holdfast" to anchor the algae to a surface.

Rhodophyta has its often brilliant color due to the pigment phycoerythrin. This alga can live at

greater depths than brown and green algae because it absorbs blue light. Coralline algae, a

group of red algae, is important in the formation of coral reefs. There are more than 4,000 species

of green algae (chlorophyta). Green algae may be found in marine or freshwater habitats, and

some even thrive in moist soil.

Only Phaeophyta class was found and it was identified as Padina gymnospora based on

its physical characteristics. Thallus was yellow-brown color, and became dark-brown color when

dried. Thallus was upright with rhizoid holdfast, fan shape, thick membrane-like texture, 5-20 cm

in height and 4-17 cm in width. White hairs were concentric arranged on the two surfaces of

thallus, and brown fluffs were covered over the base to middle part of thallus. According to the

study of Wei-Lung Wang (2010), it can be found in 2-3 m depth of water. It is distributed in Japan,

Korea, China, Hong Kong, Philippines, Taiwan and India.

Seagrass was also abundant. It was identified as Heterozostera tasmanica based on its physical

characteristics. Usually occurs subtidally in shallow coastal waters to about 8 m deep but also

found in deeper, clear oceanic water (Robertson 1984). Den Hartog (1970) described branching

of the rhizome in H. tasmanica as sympodial and used this as a diagnostic character. 

The presence of seagrass indicates that the water is not polluted and disturbed. The vast

biodiversity and sensitivity to changes in water quality inherent in seagrass communities makes

seagrasses an important species to help determine the overall health of coastal ecosystems.

Seagrasses provide food, habitat, and nursery areas for numerous vertebrate and invertebrate

species. Seagrasses help to stabilize fine sediments with their leaf and root systems and maintain

water quality.

Marine grasses, succulents and algae have a vital role in providing shelter and food for

foraging aquatic species such as fish and crabs. They also help hold the soil together, reduce the

impact of wind and waves and act as a buffer to nutrients coming from the land.

Table 5 shows the result of ecological indices from the computation using PAST

software.

Table 5. Ecological indices

Ecological indices Station 1 Station 2

Diversity (1-D) 0 0

Similarity 0 0

Evenness 1 1

Dominance 1 1

Simpson’s index of diversity(1-D) computed that the probability of two individuals belong

to the same category. It ranges from 0-1 and the greater the value, the greater the diversity.

Therefore, there is no diversity between the organism from station 1 and station 2 since in station

1, only one species was found and in station 2 as well. It was found out that there is also no

similarity between the species in two stations. The evenness pertains to how similar the

abundance between the organisms. This study is limited because the data that we have gathered

is very limited and not enough, then errors must arise. The result showed that the evenness

between organism are very similar since it has the value of 1. Both of them have also equal

dominance in the area.

CONCLUSION

Plot and transect sampling is very important in conducting an ecological study.

Paleontological Statistics(PAST) software also can be used in measuring ecological diversity.

The physico-chemical parameters results were in good condition (salinity,pH,

temperature, humidity) and the weather were in good condition too. This simply implies that the

ecosystem is not disturbed by some factors such as global warming and human activities.

Seagrass is very numerous and dominates the area and this will indicate that the water is very

healthy. However, based on the factors mentioned, the species found in the area does not show

the expected result since only macrobenthic flora was present and the macrobenthic fauna was

absent. Although there was no macrobenthic fauna that was found, it does not mean that the area

is not suitable for their survival.

In studying ecological communities, some indices are used to help assess the overall

health of the ecosystem. This includes species richness, dominance, similarity, and evenness.

There is a weakness in this study since the data that was gathered for ecological diversity are not

sufficient and is very limited. Thus, it is very possible that when the proper sampling was

conducted, there could be a macrobenthic fauna that was found.

A sufficient data must be gathered in order to achieve a better result. Ecologists must

ensure that in the gathering of data, one has to observed the proper sampling in order to avoid

some errors and biases on the study.

REFERENCES

Anderson, G. (2008). Seawater Composition. Marine Science

Cinches, V. (2013). Philippine Seas. Ocean Defender, 1

Hoyle B., & Duncan, L. (2009). Oceans, Tropical. Water Encyclopedia: Science and Issues

Kennedy J. (2014). 3 Types of Marine Algae: Seaweeds come in brown, red and green

Kingsford, M. J. (2016). Marine ecosystem . Encyclopedia Britannica .

Robertson, E.L. (1984). Seagrasses. In: The marine benthic flora of Southern Australia. Part 1. 

Tyrone, T. (2016). Marine Habitat Destruction. National Geographic.

Villaroza, S.M.(2015). Coastal Marine Ecosystem Scientific Paper

Williams, C. B. (1950). The application of the logarithmic series to the frequency of occurence of plant species in quadrats. Journal of Ecology, 38: 107-138

Wei-Lung Wang (2010). Padina Gymnospora (Kutzing) Sonder. Algae of Taiwan

Zisenis, M. (2010). Marine ecosystems. European Environment Agency, 2-3.