BAT 213

MARINE AND COASTAL ECOSYSTEMS

MANGROVES OF BALIK PULAU

TO : DR MAHADI

17TH MAY 2012

EDWARD LEE KUAN MUNHAN WAN YINONG WEI LIANPOI KHOYYEN

Introduction

Mangroves are trees and shrubs found in tropical and sub-tropical intertidal zones and

estuarine margins that have adaptations to live in saline water. The genera Avicennia, Rhizophora

and Bruguiera are widespread and characterized by modifications of the root systems for support

and gas exchange in order to tolerate harsh environment conditions such as variable salinity,

exposure to wind action and emersion period. The mangroves provide many ecosystem services,

such as stabilizing land facing the sea by trapping sediments, nutrients cycling and process

pollutants. (Hassan, Scholes, & Ash, 2005) Here, the large trees act as a surface for attachment of

sessile marine invertebrates and the organically rich sediments around prop roots and

pneumatophores support large numbers of crustaceans, molluscs and polychaetes. This area also

serves as important nurseries for the young stages of commercial fishes and shellfish. The tree

canopies also serve to support diverse insect communities, larger mammals and crocodiles. (Raffaelli

& Hawkins, 1996) The animal association with mangrove trees is regarded to be fortuitous and their

distribution is dependent on various factors. (Perkins, 1974)

Balik Pulau is the main town in the southwest of the island of Penang. It has a population of

about 120,000. As a tourist spot, it is well known for its durians and laksa. (Bindloss & Brash, 2008)

Methodology

The class was divided into groups of 4. Each group was tasked to carry out a survey on

mangrove ecosystem in Kuala Sungai Burung and Pantai Acheh. Characteristics that were observed

include;

1. Social characteristics of Balik Pulau area

2. Economic activities that involve the mangrove systems

3. Biological aspects of mangrove

- Identification of mangrove trees

- Observation of trees in association with mangrove trees

- Observation of fauna (marine and terrestrial invertebrates, larger mammals,

avifauna and insects)

Log

8.00 am : Group meet in USM.

8.15 am : Depart for Balik Pulau

9.00 am : Visit the Balik Pulau’s market

10.00 am : Journey to Pantai Acheh

12.00 pm : Journey to Kuala Sungai Burung

2.00 pm : Journey back to Balik Pulau town for lunch

3.00 pm : Depart for USM

Results

Economic uses of mangrove

Mangroves are highly valued by coastal communities. They are used for shelter, securing

food and fuel wood and in agriculture, such as rice production.

1. Trunks of the Black mangrove are used as fuel wood for cooking, thus provide good

income to nearby villagers that are involved in the wood cutting industry. It is important

to local hawkers as charcoals processed from mangrove trees are cheaper than natural

gas.

2. Mangrove trunks, can be use to construct jetties and other submerged structures

because they are resistant to rotting and to attack by fungi. The mangroves, being locally

available also makes it a cheaper construction material for the locals.

3. Fronds of Nypa fruticans, a species of palm living in association with mangroves are used

in the cottage industry in the manufacture of shingles for roof thatching. (The Australian

Institute of Marine Science, 2010)

4. “Sagu” is taken form the mangrove palm tree Metroxylon sp. (The Australian Institute of

Marine Science, 2010)

5. Hypocotyts of Bruguiera are accepted food items. (The Australian Institute of Marine

Science, 2010)

6. The bark, leaf shoots and roots of the Red mangrove trees supply tannin used for dyes,

leather preservatives and furniture stains. Mangrove tannin is important economically as

agents for the synthesis of astringents. (Kolodziej & Kiderlen, 2005) (Souza , et al., 2006)

However, the importance of bark tannins in Asian countries has declined. (The Australian

Institute of Marine Science, 2010)

7. In traditional medicine, mangrove extracts are used against human, animal and plant

pathogens. They are also used as remedy for angina, asthma, backache, leprosy and

constipation.

8. Leaves for tea and animal feed and the fruit for food. It is important to maintain local

food web and habitat for nearby animal

9. Mangrove forests can be promoted as areas for recreation and eco-tourism. (Global

significance of Malaysian mangroves, 2005) It will bring about development of nearby

areas and generate income and creating job opportunities to local industries like

hospitality, food and beverage and transport.

Economic use of organisms in association with mangroves

A variety of organisms live in association with mangrove communities. Diverse marine

organisms inhabit underwater prop roots complexes and tidal channels. Commercially important

fishes and shellfishes utilize mangrove habitat at some point in their life. Terrestrial organisms and

birds utilize the forest floor, root complex and tree canopy. (Newfound Harbor Marine Institute)

1. Fishes are among the many organisms that rely on mangroves at some point in their

lives. At the study areas, commercially important fishes such as

Scientific name Local nameArius sagor Ikan duriArius. argyropleuron Ikan duriStolephorus insularis Ikan bilisStolephorus commersoni Ikan bilisLiza subviridis BelanakSelaroides leptolepis SelarScomberoides commersonianus TalangRastrelliger kanagurta Ikan kembungChiloscyllium punctatum Ikan yuDasyatis zugei Pari ketukaPampus chinensis BawalMegalaspis cordyla CencaruCynoglossus kops Ikan LidahCynoglossus lingua Ikan lidah

Note: Fish in bold are fishes actually observed in the market.

Table derived from “Table 2. Distribution of Species by Sampling Stations and Sampling Date During the Study,’ by Amir

Shah Ruddin, Yusri Yusuf and Siti Azizah, 2006, Ecological Survey on Mangrove Forests : A Case Study of Balik Pulau and

Pantai Acheh, p. 84. Copyright 2006 by Penerbit Universiti Sains Malaysia and “Table 5. Fishes Recorded from the Pantai

Acheh Mangrove Area,” by Amirrudin Ahmad, Yusri Yusuf and Siti Azizah, 2006, Ecological Survey on Mangrove Forests : A

Case Study of Balik Pulau and Pantai Acheh, p 104. Copyright 2006 by Penerbit Universiti Sains Malaysia.

Other species of fish common to the mangrove swamps is ikan belacak, Periophthalmus

chrysospilos.

2. Gastropods and crustaceans are also important members of the mangrove ecosystem

here. Some are harvested and sold in the market as food items.

A list of gastropods that can be found in the study areas include

Scientific name Local nameCerthidea obtuse Siput BelitungTelescopium telescopium Siput BelitungLittorarina conica Mangrove periwinkleNasarius olivaceus Mud whelk(Ahmad, Yusuf, & Siti Azizah, 2006)

Note: Gastropods in bold are observed in market

Crustaceans that can be found in the study area are

Scientific name Local nameScylla olivacea Mud crab*/ Ketam bakauPortunus pelagicus Flower crabUca spp. Fiddler crabs / Ketam RebabUca rosea Rosy fiddler / Ketam RebabEpisarma spp. Vinegar crabSelatium sp. Mangrove tree-dwelling crabVaruna sp. Paddler crabBalanus sp. BarnaclesPerisesarma sp. Sesarmine crabs(Ahmad, Yusuf, & Siti Azizah, 2006)

Note: Items in bold were actually observed in the study area.

*Indicate that crabs are sold in market

Discussion

1. Avicennia spp. is a flowering plant, commonly

known as api-api in Malay which means fire.

There are vertical roots called pneumatophores

projecting from the mud. It is used for gas

exchange. The flowers are fragrant and rich in

nectar and are pollinated by insects.

2. Bruguiera spp. is a small genus and commonly known as white mangrove. It grows well in

areas which are inundated by spring

tides.

3. Rhizophora spp. is a tropical mangrove

tree and sometimes called true

mangrove. It has stilt-roots that

elevate the plant above the water and

allow them to take in oxygen during

inundated by tides.

Figure 1. Avicennia spp.

Figure 2. Bruguiera spp.

4. Nypa fruticans commonly known

as nipa palm, it is a species of

palm. The nipa palm has a

horizontal tree trunk that grows

beneath the trunk and only leaves

and flowers grow upwards above

the surface. It germinates by

water.

5. Acrostichum spp. is a fern species. It is commonly

known as leather fern or leather swamp fern. It

does not withstand prolonged immersion, but it

needs wet roots. It can tolerate with high saltwater.

Figure 4. Nypa fruticans

Figure 5. Acrostichum spp.

Mangroves are remarkably uniform communities. Only a few types of trees grow together

and are usually rather similar in habit and appearances. Different types of mangrove species have

adaptations that allow them to live in various kinds of soil. This contributes to the formation of

different vegetation zone in a mangrove community. The presence of different zones is a unique

feature of the mangrove forest. (Mansor, Sulaiman, Jaafar, & Mansor, 2006)

According the same study, about 25 families and 38 species of mangrove plants have been

identified at four locations in Balik Pulau and Pantai Acheh mangrove forests. Eight families of

mangrove plant were recorded, each represented by a species.

Family Species

Acanthaceae Acanthus ilicifolius

Pteridaceae Acrostichum aureum

Avicenniaceae Avicennia marina

Rhizophoraceae Bruguiera cylindrica

Leguminosae Derris trifoliata

Compositae Pluchea indica

Combretaceae Terminalia catappa

Meliaceae Xylocarpus granatum

23 families and 39 species of mangrove plants were observed in the locality of Kuala Sungai

Burung according to the same study. Species common to both areas are from the family

Avicenniaceae and Rhizophoraceae. The most common mangrove plant species found was Avicennia

marina. The colonies of A.marina were recorded from 10m of the sea front up to 500m inland.

Mangrove crabs seek cover, from predation and desiccation on the swamp floor. They may

dig burrows or inhabit communal “crab-runs” and some adult species may even climb trees e.g

Aratus pisoni. Swimming crabs, Scylla serrata, make burrows in the bank from which they pounce

upon prey. (Perkins, 1974)

Polychaetes are a rare occurrence in tropical mangrove mud. (Perkins, 1974) But a study

Amir Shah, Yusri Yusuf and Siti Azizah (2006) identified Limnodrilus sp. (Family : Tubificidae) and 5

species of polychaetes along the Balik Pulau Forest Reserve.

Reproduction strategies of mangroves;

Mangrove reproduction has adapted to be successful in salt water environment. Most

species of mangroves possess small, sticky pollen grains; pollination agents include bees, bats and

birds. The fruits and seedlings of mangroves float and this is the main mechanism of dispersal.

Most mangroves such as species of Rhizophora, Bruguiera, and Avicennia are reproduced by

vivipary. Vivipary is the precocious and continuous growth of off-spring whilst still attached to the

maternal plant; the fertilized seed germinate at the same time still attached to the parent plant.

Once germinated, the seedling grows either within the fruit or out of the fruit to form a

propagule which can produce it own food through photosynthesis. Propagule mostly can see in

Rhizophora spp. and Bruguiera spp. The mature propagule will drop into water and it can travel in a

great distances. Propagule can survive desiccation and remain dormant for a year before it get a

suitable environment to root. Once is suitable to root, it changes its density and float vertically

rather than horizontally.

Most of the mangroves do produce large seeds and fruits. The food reserve in the large seed

provides the seedling with energy to help it through the early stages of establishment. Most of the

mangroves produce many seeds. Many seedlings have been produce annually to increase the rate of

survival.

Mangroves in land stabilization and storm protection.

Mangrove act as pervention of the coastal erosion. It minimise the action of waves and thus

prevent the coast from erosion by waves action. The root systems of the plants hold substrate firm,

prevent it from being washed away by waves action. Another work has proved that mangroves form

‘live seawalls’, and are very cost effective as compared to the concrete seawall and other sturucutes

for the protection of coastal erosion ( Harada et al., 2002 ). Compared to seadyke, mangrove are

more effective in protecting the coastal land from erosion as even seadyke is not durable from wave

erosion and it require maintainence cost as proved in the Red River Delta, Vietnam. The planting of

mangrove has cost of US$ 1.1 million but has helped reduce maintenance cost of the seadyke by US$

7.3 million per year (World Disaster report, 2002). So it is estimated the same at Balik Pulau.

For storm protection, like any other forest mangrove protect the coastal area from storm by

reducing the wind and wave force when it hits the vegetation in the mangrove. We can also say that

the mangrove act as a green wall that protect us from strom. The best example on finds is the super‐

cyclone which occurred on the 29th October 1999 with a wind speed of 310 km/hr along the Orissa

coast (India) and played havoc largely in the areas devoid of mangroves. On the contrary, practically

no damage occurred in regions with luxuriant mangrove growth ( K. Kathiresan, 2005 ). We do not

have large storm and cyclone at Balik Pulau as we are protected in straits of Melacca, but it do

protect us from tsunami by reflect and resists tsunami energy, thus reducing the inudation depth

and area. It also trap driftwood and other debris, thus reducing human injuries and property

damage. Last but not least, it also prevent people from being washed out to the sea ( Tan Cheng Li,

2005 ).

Importance of mangroves to marine organisms.

Mangroves shed and drop a few ton of leaf litter per acre per year. The dropped leaves are

quickly broken down by bacteria and fungi into the water and provide food for the sea-life.

Mangroves are also providing shelter for the marine organisms. For example, the trunks and roots of

mangroves which are regularly submerged by tides are a good place for bivalves like oyster and

barnacles to attach. The mud is the perfect medium to create burrows in crabs and snapping

shrimps.

Mangroves also act as a natural nursery ground. This is because in the mangrove areas, the

water level is shallow, warm water temperature due to various decaying activities and water current

is low. Many fishes lay eggs in tangled root of mangroves tree and later hatch and grow with needed

nutrients available.

Mangrove trap debris and silt, stabilizing the near shore environment and clarifying adjacent

open water, which facilitates photosynthesis in marine plants. The fringing network on mangrove

buffers natural forces such as hurricanes, wave action, tidal change and run-off, preventing soil loss

with its firm, flexible barrier and protecting the marine organisms. Mangrove forest is also an ideal

sanctuary for avifauna. It protects avifauna from harsh condition during migration.

Like many natural ecosystems, mangroves (of Balik Pulau in particular) face many threats in

this time.

Urbanisation caused coastal mangroves to be cleared for human inhabitation (K.Kathiresan,

2005). During past few years, as the land at the east coast of Penang Island had been fully used.

People start to develop the west coast of the island especially along coastal area of Balik Pulau. This

becomes a threat to the mangrove forest as this activity need to clear off the mangrove forest first

before buliding anything on it. Some new housing area include Taman Jelita, Taman Nelayan Kuala

Sungai Pinang, Kampung Pantai Acheh, Kampung Permatang Pasia, Kampung Sungai Rusa and so on

(Wikimapia.org ).

Agriculture and aquaculture activity are important causes of the loss of mangroves (Hassan,

Scholes, & Ash, 2005). There are no major agriculture activities in Balik Pulau but there are still minor

ones such as agriculture project that conducted on Permatang Pasir and paddy plantation along the

river before Kuala Sungai Burung. But aquaculture activity causes the highest damage to the

mangrove forest. There are several aquaculture farms for both shrimp and fish along the coast such

as DEW SEAFOOD Grouper Farm, Lim Kooi Hak’s Prawn Farm, and lots more at Kuala Sungai Pinang.

Overexploitation of mangroves for timber, fuel and charcoal is also a threat to mangroves.

There are also no compulsory replantation to replace those that been chopped off.

Pollution also causes the destruction of mangrove. There are no large factory or industrial

area at Balik Pulau so the pollution is caused mainly by domestic and agriculture waste that flows

along the river and accumulate at the river mouth where the mangrove are found. Prevention of

freshwater flow and tidal flow also caused the destruction of the mangrove forest. The mangroves

thrive on area that are exposed to freshwater from stream at the same time being washed by sea

water. Building the dam at Teluk Bahang caused poor flow of freshwater which exposes the

mangrove area to high salinity and cause poor growth of mangrove.

Great tidal fluctuations bring about greater tidal range which can help mangrove forests to

colonize extensively. A greater tidal range increases the intertidal area and encourages the growth of

mangroves if the slope is smooth. (Kathiseran)

Also, tidal fluctuations reduce competition due to alternate wetting and dryness. The tides

also transport clean water and nutrients into the system, export wastes, detritus and at the same

time, help dispersal of propagules. The tides flush excess salt away during periods of high

evaporation thus preventing highly saline soil. (Mangrove Morphology & Physiology)

Large tidal ranges can affect the root systems of mangroves. Mangroves prefer large tidal

range, which causes little undercurrent wave action. (Guyana Mangrove Restoration Project)

Anaerobic environment is an environment with little available oxygen.

Every part of the plant need oxygen for respiration and anaerobic condition of soil is a

challenge for mangrove. Although the mangrove produce oxygen by photosysnthesis but it is

confined to the leaves. The oxygen is blocked from entering the soil by the water on top of soil

blocks.

The soil, in waterlogged conditions will use up the soil oxygen and it will become anaerobic.

To overcome this challenge, pneumatophores, prop root is used by mangrove to transport oxygen

from the air to the root below the ground.

Red mangroves have prop roots that extend from the trunk while the black mangroves have

small air roots (pneumatophores) that grow vertically from the soil, surrounding the parent tree.

During periods of low tide, these structures take up air through its open passages and transport the

air to root tissues. Lenticels, cover the surface of the roots and facilitate air absorption into spongy

tissue (aerenchyma). The spongy tissue then distributes oxygen throughout the plant via the osmotic

pathway. (Environmental factors and adaptations) (Lenticel, 2012)

Fauna found in study area;

1. Crustaceans

Figure 6. Fiddler crab

Figure 7. Fiddler crab

Figure 8. Barnacles

Figure 9. Sesarmine crabs

2. Mudskipper

Figure 10. Periophthalmus chrysospilos

3. Birds

Figure 11. Unidentified bird species

Conclusion

Mangroves are highly valued by a large group of communities, as it provides, among others, livelihood, storm protection, ecosystem services and habitat. However, many mangrove areas have been degraded worldwide and habitat conversion of mangroves is widespread. Estimates of the loss of mangroves form countries show that 35% of mangrove forests have disappeared in the last two decades. As such, measures must be taken to sustain the mangroves and one method is by holistic implementation of management.

Bibliography

(n.d.). Retrieved May 15, 2012, from Mangrove Morphology & Physiology: http://www.nhmi.org/mangroves/phy.htm

Global significance of Malaysian mangroves. (2005, October 18). Retrieved from The Star: http://thestar.com.my/lifestyle/story.asp?file=/2005/10/18/lifefocus/12218662&sec=lifefocus

The Australian Institute of Marine Science. (2010, May 10). Retrieved from Mangrove uses.

Lenticel. (2012, April 10). Retrieved May 14, 2012, from Wikipedia: http://en.wikipedia.org/wiki/Lenticel

Ahmad, A., Yusuf, Y., & Siti Azizah. (2006). Fishes and Other Invertebrates Fauna in Pantai Acheh Forest Reserve. Penerbit Universiti Sains Malaysia.

Bindloss, J., & Brash, C. (2008). Kuala Lumpur, Melaka & Penang. Lonely Planet.

Environmental factors and adaptations. (n.d.). Retrieved May 14, 2012, from School of Forest Resources & Conservation.

Friends Of Mangrove. (n.d.). Retrieved from http://www.friendsofmangrove.org.my/view_file.cfm?fileid=5

Guyana Mangrove Restoration Project. (n.d.). Retrieved May 15, 2012, from Distribution of Mangroves: http://www.mangrovesgy.org/index.php?option=com_content&view=article&id=90&Itemid=73

Hassan, R., Scholes, R., & Ash, N. (Eds.). (2005). Ecosystems and Human Well-Being : Current State and Trends (Vol. 1). Island Press.

Kathiseran, K. (n.d.). Ecology and Environment of Mangrove Ecosystems. In K. Kathiseran.

Kolodziej, H., & Kiderlen, A. F. (2005). Antileishmanial activity and immune modulatory effects of tannins and related compounds on Leishmania parasitised RAW 264.7 cells.

Mansor, M., Sulaiman, B., Jaafar, A., & Mansor, A. (2006). Mangrove survey in Balik Pulau and Pantai Acheh Mangrove Forests. Penerbit Universiti Sains Malaysia.

Newfound Harbor Marine Institute. (n.d.). Retrieved May 14, 2012, from Seacamp Association Inc web site: http://www.nhmi.org/mangroves/index.htm

Perkins, E. J. (1974). The Biology of Estuaries and Coastal Waters. New York: Academic Press Inc, (London) Ltd.

Raffaelli, D., & Hawkins, S. (1996). Intertidal Ecology. London: Chapman & Hall.

Souza , S. M., Aquino, L. C., Milach Jr, A. C., Bandeira, M. A., Nobre, M. E., & Viana, G. S. (2006). Antiinflammatory and antiulcer properties of tannins from Myracrodruon urundeuva Allemão (Anacardiaceae) in Rodents. Phytotherapy Research.

Wikimapia.org

Prof. K. Kathiresan. (2005) .Biodiversity of Mangrove Ecosystems Centre of Advanced Study in Marine Biology, Annamalai University

Spalding, M. (1997). The global distribution and status of mangrove ecosystems. International Newsletter of Coastal Management

Mastaller, M. (1989). Rehabilitation der Lagune Ciengaga Grande de Santa Marta, Kolumbien.