Estuaries Ecosystem

PAPER

Arranged in partial fulfillment

Basic Ecology

that guided by Prof. Dr. Hj. Mimien Henie Irawati, M.S. and

Dr. Fatchur Rohman, M.Si.

Arranged by:

09th Group

Class A - Offering A

1. Lailatul Qodriah (100341400698)

2. Devi Nur Octaviandari (100341400704)

The Learning University

UNIVERSITY OF MALANG

FACULTY OF MATHEMATICS AND NATURAL SCIENCES

DEPARTMENT OF BIOLOGY

January 2012

PREFACE

Gratitude Praise presence writer prayed Allah SWT, because of the blessing

of his paper, entitled “Estuaries Ecosystem” this in turn can be resolved. The paper is

organized to fulfill the task of Histology course that guided by Prof. Dr. Hj. Mimien

Henie Irawati, M.S. and Dr. Fatchur Rohman, M.Si.

Furthermore, we say great thank to:

1. Prof. Dr. Hj. Mimien Henie Irawati, M.S. and Dr. Fatchur Rohman, M.Si.

guided course as lecturers and assistant lecturers are always accompanied

and guided us in preparing this paper.

2. Students Biology offering A years of 2010.

3. All those who have helped in the process of preparing this paper.

A part from all the shortcomings of writing this paper, both in composition

and writing the wrong, the author pleaded for forgiveness and hope that the writing of

this paper is useful especially for writers and the readers. We as authors are aware

that the writing of this paper is still far from perfection, and therefore, we always

expect criticism and constructive suggestions from you for improvements in the

preparation of the next paper.

Finally, may Allah Swt. always gives His guidance to anyone who loves

science and education. Amin Ya Robbal Alamin.

Malang, January 2012

The writers

CONTENTS

Cover ................................................................................................................... i

Preface ................................................................................................................. ii

A. Background ................................................................................................. 1

1.1 Problems ........................................................................................... 1

B. The Definition and Classification of Estuaries Ecosystem.......................

C. The Physical Characteristic of Estuaries Ecosystem................................

D. The Biological Features of Estuaries Ecosystem.......................................

E. The Important of Estuaries Ecosystem .....................................................

References

ESTUARIES ECOSYSTEM

A. BACKGROUND

Estuaries are unique transition ecosystems—complex, dynamic, productive, and

in many ways different from either the adjacent ocean or the river upstream.

Estuaries provide many goods and services to humans and other organisms.

Examples include fish and shellfish production, water purification, shoreline

stabilization, wildlife habitat, and recreational opportunities.

With a twice-daily ebb and flood of the tide, salt water and fresh water mixing,

and rapid fluctuations in temperature and salinity, estuaries can be difficult places

to live. But the plants and animals that thrive there have developed remarkable

adaptations to these difficult conditions—adaptations for feeding, reproducing,

rearing their young, avoiding predators, and regulating their bodies’ temperature

and salt concentration.

Estuarine ecosystems and their inhabitants thus are by nature resilient. At the

same time, however, past changes and present threats make them highly

vulnerable. Human history and economic development are intimately linked to

estuaries. Estuaries provide abundant, easy-to-access fish and shellfish. We build

cities on their shores and ports in their sheltered harbors. We come to the sea to

breathe the salt air and be renewed.

Some of the ways we use estuaries change these ecosystems, often significantly.

We selectively harvest plants and animals. We consciously or inadvertently

introduce nonnative organisms, including pest species. We dredge navigation

channels, build jetties, fill tidelands, dike salt marshes, dump wastes, and more.

Although some of these uses have economic and other benefits, they often

adversely affect the natural goods and services that estuaries provide to society.

So, here we will study more deeply about the estuaries ecosystem including what

is the estuary, kind of estuaries ecosystem, physic characteristics of it, and biota

or organisms which live in. And hopefully, we can maintain the estuaries

ecosystem that are not just exploit them.

1. Objectives

a. To know the definition and classification of estuary

ecosystem

b. To know the physical characteristics of estuary ecosystem

c. To know biological feature in estuary ecosystem

d. To know the important of estuary ecosystem

B. THE DEFINITION AND CLASSIFICATION OF ESTUARIES

ECOSYSTEM

Estuaries are semi-enclosed bodies of water where fresh water from rivers

or streams mingles with the salt water of the ocean. Estuaries trap nutrients and

sediment that is carried from the land by rivers and from the ocean by tides.

Estuaries are characterized by a constant mixing of these nutrients with the rise

and fall of the tide. These conditions create an enormous amount of plant and

animal life. Estuaries are therefore one of the most productive types of

ecosystems on earth.

Estuaries can be found in flat river deltas or steep-sided coastal fiords.

They may have different components, such as tidal mud flats, lagoons, salt

marshes and sand dunes. Although estuaries make up only 3% of the coastline in

BC, they are used by approximately 80% of all wildlife species on the coast.

Estuaries are also popular places for people, and unfortunately many of them have

been lost to urban and agricultural development.

C. PHYSICAL CHARACTERISTICS OF ESTUARIES ECOSYSTEM

1. Currents

In the estuary, river and tidal currents play very important roles in mixing

the lower and upper layers of water. This estuarine circulation, as we will see

later, is a crucial factor determining the high productivity of estuaries.

When sea-water enters an estuary in the northern hemisphere, it flows

clockwise to the 'right,' and freshwater flowing down-river moves also

clockwise, thus flowing to the other side. Due to this coriolis force, one side

in the estuary is often saltier than the other side.

2. Ice

Some of our more northern estuaries have ice cover for up to four months

of the year. Ice cover helps provide a constant temperature in the mud, which

is beneficial for many marine organisms. Once the ice melts, there is a very

sudden increase in freshwater content, contributing to the variability in

salinity.

3. Salt

Salinity constantly changes in estuaries. When freshwater mixes with

saltwater it is called brackish water. The water of estuaries and salt marshes

can be brackish.

4. Salinity

Salinity is an important feature of estuaries. Estuary water is a mixture of

freshwater and saltwater in proportions that vary according to the location in

the estuary. An out-going tide can reduce salinity slightly.

The degree of salinity can also be influenced by factors such as the level

and intensity of the tides, the melting of snow in the spring, heavy

precipitation, and dry periods during the summer season.

The salinity can be weak upstream in the estuary, about 0.5 ppt, and very high

downstream, up to 30 ppt. In the sea, the average salinity is 35 ppt. The zone

where freshwater changes to saltwater is called a pycnodine.

The freshwater from rivers is lighter than saltwater, so it has a tendency

to stay on top of the saltwater. If the estuary is deep enough, the saltwater

from the sea will travel up the estuary by passing under the freshwater while

the freshwater going down the river will stay above the saltwater layer and

enter the sea. This is called a salt-wedge estuary. This kind of estuary tends to

form in situations with low turbulences; therefore, little mixing occurs. It

often happens in certain places that there is virtually no salt content at the

water's surface, but the salinity is very high at the bottom. If the estuary is

shallow or where water turbulence is great, the salt and freshwater will mix

and the salinity change is gradual.

5. Sediment

An estuary is constantly changing and tends to accumulate sediments.

Sediments come from rivers, streams and brackish marshes located inland,

and salt marshes and sand dunes located near the mouth of the estuary.

Sediments can be composed of animal and plant matter, as well as inorganic

material, such as mud or sand.

6. Temperature

Temperature is one of the main elements influencing reproduction of

invertebrates and fish. Since estuaries are shallow and semi-enclosed,

temperatures can be slightly higher than in open areas, providing the levels

required for some species to lay their eggs. Cold temperatures can negatively

affect fish in their planktonic stages, slowing down the hatching and growth

of the young.

7. Tides

With the rise and fall of tides, nutrients are brought into the estuary. The

movement of tides also causes turbulence, resulting in an upwelling of water,

which brings nutrients from the bottom of the estuary to the surface.

The further up the estuary you go, the more delayed the tide becomes.

Since estuaries are usually funnel-shaped, incoming tides at the mouth tend to

increase in amplitude as the channel narrows. The frictional contact from the

shore and bottom act against the tide and tend to lower the height of the tide.

With these counteracting forces, it can be difficult to predict whether the tidal

range will be smaller or greater at the head of the estuary. The rise and fall of

tides can be felt far up-river, especially in bigger estuaries.

D. THE BIOLOGICAL FEATURES OF ESTUARIES ECOSYSTEM

In the summer there is an abundance of biological activity in the estuary. The

tides, currents, and wind bring nutrients to the water's surface (upwelling).

Plentiful nutrients combined with warm shallow waters set the stage for a

profusion of activities. Some invertebrate animals, birds, and fish are able to take

advantage of these factors. Estuaries and other coastal ecosystems tend to be in

areas of high productivity and therefore have high-quality habitats for many

species of wildlife (Anonym, 2009).

Plankton

Phytoplankton are minute plants such as dinoflagellates. Phytoplankton, along

with bacteria and fungi, are the basis of life in the estuary and are carried by the

currents. In order to survive, they must remain in a place where the salinity fits

their needs. They use the sun and the nutrients from rivers and salt marshes to

feed themselves.

Zooplankton are the tiny animal part of plankton. In estuaries, zooplankton

benefit from an abundant food supply: phytoplankton, microscopic algae,

bacteria, and detritus coming from dead plants and animals.

Plants

Plants modify coastal ecosystems by trapping sediments, slowing down currents,

producing food, and giving shelter to organisms. Eelgrass is a major source of

food for a whole community of animals and plants. Small fish such as the

Mummichog, Sticklebacks, and the fry of the Striped Bass and Gaspereau shelter

and feed in Eelgrass beds. This plant helps to stabilize the bottom with its roots,

allowing organisms such as Crabs and Lobsters to move around on it.

Accumulations of dead Eelgrass are often found along beaches, enriching other

ecosystems.

Molluscs

Molluscs are plentiful in estuaries. Some hide in the sediment while others live on

sediments or plants. Molluscs can be carnivores or can feed by filtering water.

Some graze on microscopic algae that live on the estuary bottom and on the

vegetation. Others feed on detritus from dead animals and plants. Molluscs are an

important source of food for other animals that live or stay in the estuary such as

the Winter Flounder, Mud Crab, Ducks (such as Scaup), and Raccoon.

Crustaceans

Lobster, Crabs, Sand Shrimp, and Amphipods (a type of small shrimp) are found

in estuaries. They can serve as food for birds, fish, and mammals.

Crab and lobster

Crabs and lobsters feed on molluscs and other living or dead organisms. They use

their claws to break shells. Lobsters can eat mussels, crabs, oysters, sea stars, and

worms. Crabs eat mussels. When mussels are cultivated using 'collectors' they are

the size of a grain of pepper when first installed. Crabs are often found on these

collectors.

Worms

Worms are prey for a great variety of animals, such as crustaceans, fish, and

birds. Some are carnivores, others eat seaweed or detritus (non-living materials).

Some worms, like the clam worm, move freely through the mud, while others

build permanent tubes through which they filter particles from the water.

Fish

Fish use the estuary for spawning, the development of fry (very small fish), and as

nursery areas for juveniles. Many species have migratory patterns that take

advantage of the plankton. Food, as well as shelter, is abundant in an estuary. The

estuary is a transition zone for marine species travelling from the sea to rivers,

and for freshwater species travelling from rivers to the ocean.

Birds

Birds are very mobile and their rhythm is associated with that of the tides, their

food, and the movement of the water. Some birds, such as the Canada Goose, feed

in the intertidal zone at low tide. Some, such as the Black Duck, feed in shallow

waters. Cormorants, mergansers, and scaups feed in deeper water by diving from

the surface. Terns, Osprey, and Kingfishers dive from above the surface.

E. THE IMPORTANT OF ESTUARY ECOSYSTEM

Estuaries provide many “ecosystem services.” These are functions performed by

natural systems that are necessary for human welfare. In the past, these functions

were often overlooked and estuaries were considered useful only after they were

“reclaimed” for human use. The following are some examples of how we benefit

from estuaries (Schuchardt, 2009).

Erosion control and storm surge protection: Vegetation in estuaries helps to

anchor sediment and soil along river banks and shorelines. This prevents stream

flows, rainwater and waves from scouring away the land. Estuaries also build up

deposits of mud, silt and sand. This natural barrier helps to dissipate the energy of

large waves that can otherwise inflict serious damage on human life and property

(Schuchardt, 2009).

Water Quality

Estuaries function as natural water purification systems. Vegetation and fine

sediments in estuaries filter water as it flows from the land to the ocean. Bacteria

living in the sediments of estuaries can also help to break down certain pollutants.

Atmospheric Gas Regulation

Estuaries tend to be “carbon sinks,” since carbon dioxide is absorbed in the

photosynthesis carried out by the prolific plant growth. Carbon dioxide is released

when wood or fossil fuel is burned, or when estuaries are filled in. It is one of the

greenhouse gases that are thought to be at least partly responsible for climate

change.

Nutrient Cycling

Estuaries help to regulate concentrations of nutrients such as nitrogen and

phosphorous in the marine environment. These nutrients are needed for plant

growth but in excess can cause harmful algae blooms and rob the water of

oxygen.

Habitat for Plants, Shorebirds & Other Animals

As described above, many species of animals spend all or a portion of their lives

in estuaries. Some of these species, such as Pacific Salmon, have direct

commercial value. Others are important as part of the overall function of many

ecosystems. Estuaries contribute greatly to the biodiversity of the marine

environment.

Education, Recreation & Tourism Opportunities

Estuaries are peaceful, beautiful landscapes. Artists, canoeists, bird/wildlife

watchers, hunters, fishers, photographers, scientists, children and teachers are all

attracted to estuaries. The special qualities of estuaries make them ideal study and

teaching environments.

Estuaries are not only one of the most biologically productive types of

ecosystems, they are also one of the most valuable. It is difficult to attach

monetary worth to these ecosystem services, especially since most are needed for

life on earth and are not replaceable with human-made systems, at any cost.

Nevertheless, some people believe that estimating the value of ecosystems, even

imperfectly, will help people to make better land use decisions. Thus in a 1997

study, a conservative estimate of the value of ecosystem services performed by

estuaries was US$22,832 per hectare per year (Anonym, 2009).

REFERENCE

Schuchard. Bastian, Scholle Jorg. 2009. Wadden Sea Ecosystem.

Netherland:Simon Associates, Inc. Publishers.

Odum, E.P., 1989. Ecology and Our Endangered Life-Support Systems. USA:

Sinauer Associates, Inc. Publishers.

PERNYATAAN :

1. Estuaria dapat dianggap sebagai zona transisi atau ekotone.

Estuaria merupakan daerah campuran antara air laut dan air tawar. Biasanya,

berupa teluk atau muara sungai. Jadi, salinitas air pada estuaria inipun tidak

asin dan tidak tawar.

2. Komunitas estuaria terdiri dari campuran antara jenis- jenis endemik dan

jenis- jenis yang datang dari laut ataupun dari air tawar.

Banyak sekali jenis- jenis komersial seperti tiram dan kepiting yang hidup di

daerah estuaria. Selain itu, ikan salmon dan belut juga sering bergantung pada

estuaria. Karena estuaria bisa dijadikan sebagai tenpat tinggal selama jangka

waktu tertentu saat mereka melakukan migrasi dari air asin ke air tawar.

3. Perairan estuaria merupakan salah satu alasan ekonomi utama untuk

melestarikan habitat ini.

Karena perairan ini merupakan merupakan tempat yang sangat produktif salah

satunya bagi beberapa jenis udang yang masuk ke perairan ini pada masa

mudanya (juvenile stage) dan tempat bertemunya biota air laut dan air tawar

yang memiliki nilai komersial.

4. Estuaria merupakan suatu perangkap nutrien yang sebagian bersifat fisik dan

sebagian lagi bersifat biologi.

Pada daerah estuaria ini terjadi terjadi pembentukan satuan- satuan organik

dan detritus serta perolehan kembali nutrien dari endapan dalam oleh aktivitas

mikroba, akar tumbuhan dan hewan penggali yang menciptakan suatu sistem

penyuburan sendiri

5. Estuaria digunakan sebagai tempat asuhan dalam daur kehidupan beberapa

jenis udang.

Udang dewasa bertelur di lepas pantai dan pada tahap larva muda, udang

bergerak ke arah pantai masuk ke dalam estuaria setengah tertutup. Pada

daerah estuaria inilah larva udang dan udang remaja menemukan makanan

dan perlindungan di dalam teluk-teluk dangkal sehingga mereka dapat

berkembang dengan cepat. Selanjutnya udang yang telah menjadi dewasa

bergerak kembali ke selat- selat dan lautan terdekat untuk di panen.

6. Estuaria memiliki keanekaragaman jenis produsen yang terprogram

berfotosintesis sepanjang tahun.

Estuaria sering sekali memiliki tiga jenis produsen yang menguasai dunia,

yaitu makrofit (alga, rumput laut dan rumput di paya- paya), mikrofit bentik

dan fitoplankton yang dapat berfotosintesis dan memberikan makanan pada

organisme lain yang hidup di daerah estuaria sehingga dapat menunjang

kehidupan organisme- organisme yang hidup di perairan ini.

7. Perairan estuaria merupakan suatu ekosistem yang dengan permukaan air

berfluktuasi yang bersubsidi.

Gerakan pasang surut air pada perairan estuaria dapat membuang limbah dan

membawa makanan serta nutrien, sehingga organisme yang hidup di

dalamnya dapat mempertahankan eksistensi sesilnya yang tidak memerlukan

banyak pengeluaran energi metabolisme untuk mengeluarkan kotoran badan

dan mengumpulkan makanan.

8. Dilihat dari sudut pandang manusia, estuari merupakan suatu lingkungan yang

multi guna.

Karena perairan estuaria secara umum dimanfaatkan manusia untuk tempat

pemukiman, tempat penangkapan dan budidaya sumberdaya ikan, jalur

transportasi, pelabuhan dan kawasan industri.

9. Organisme yang dapat hidup dan membentuk koloni di eustaria harus

memiliki kemampuan beradaptasi secara khusus agar bisa bertahan hidup.

Kemampuan adaptasi dapat berupa adaptasi morfologis, fisiologis maupun

tingkah laku. Contoh adaptasi fisiologis organisme estuaria yaitu memiliki

kemampuan osmoregulasi yang baik seperti pada hewan jenis Mollusca.

10. Ekotone adalah peralihan antara dua atau lebih komunitas yang berbeda.

Daerah ini adalah daerah pertemuan yang dapat berbentuk bentangan luas

tetapi masih lebih sempit/kecil jumlah populasinya dari komunitas sekitamya.

Komunitas ekotone biasanya banyak mengandung organisme dari masing-

masing komunitas yang saling tumpang tindih, dan sebagai tambahan, ataupun

sebagai organisme yang khas tidak terdapat pada masing-masing komunitas

pendampingnya. Seringkali terdapat kecenderungan jumlah jenis dan

kepadatan organisme di wilayah ekotone lebih besar daripada komunitas

sekitarnya Kecenderungan ini akhirnya akan meningkatkan keanekaragaman

dan kepadatan wilayah ekotone dibanding komunitas pendampingnya.

keadaan ini dikenal sebagai pengaruh tepi.

11. Estuaria jenis fyord adalah pantai yang dalam, berbentuk U melesak ke bawah

karena pengaruh glacial dan biasanya dengan bentuk yang dangkal pada

mulutnya yang terbentuk oleh timbunan glacial.

Pantai ini biasanya lebih dangkal namun dalam karena pengaruh dari glacial

tersebut.

12. Glasial adalah daerah es

Glacial itu sendiri merupakan dari bekas dari zaman es yang mungkin masih

terdapat pada bagian yang ada dalam bumi kita.

13. Estuaria hypersaline adalah aliran masuk air tawar kecil

Pada aliran ini membedakan pasang surut rendah yang mengalami penguapan

yang sangat tinggi dan salinitasnya dapat melebihi air laut

14. Goba-goba adalah nama sebutan untuk lahan bercocok tanam Rumput Laut di

laut.

Goba-goba ini merupakan suatu lahan yang memungkinkan dimanfaatkan

para warga dalam menghasilkan rumput laut yang nantinya akan dijual

dipasaran

15. Rawa bakau merupakan sekumpulan pohon bakau yang ada di suatu pantai

Rawa bakau ini dimanfaatkan masyarakat untuk menahan agrasi yang terjadi

pada pantai. Selain itu rawa ini juga dapat dimanfaatkan oleh para warga

untuk memperoleh kepiting

16. Dinoflagelata komunitas plankton yang terbiasa dengan intensitas cahaya.

Dinoflagelata ini tergolong sebagai komunitas makhluk hidup yang ada pada

daerah yang memiliki intensitas cahaya yang terang dan nutrient organic.