Food Webs in Wetlands

8/6/2019 Food Webs in Wetlands

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Food Webs in Wetlands

(The introductory material on general ecology and food webs is mostly from:

Caduto, M.J. 1985. Pond and Brook. Hanover, N.H.: University Press of New England.276p.)

What is Ecology?

The word ecology comes from the Greek word oikos which means "home" andso ecology is the study of organisms with themselves, each other, and theirhabitattheir home.

A population is a group of the same species living in the same place at thesame time.

In ecologicial terms, a community refers to all the organisms interacting withone another and sharing available resources within a defined area.

An ecosystem encompasses all communities in a particular area as well as allthe abiotic factors affecting that area.

Ecosystems sort of fade into one another as them meet. They are not sharplydefined. These in-between zones are calledecotones or ectones.

Energy and the Food Web

Just like any other sort of system, an ecosystem requires energy to operate. Energyfor an ecosystem comes from the sun in the form of photons. When a photon ofenergy from the sun hits a green plant or an algae, it triggers a complicated chemicalreaction in the chlorophyll pigments: photosynthesis. This is the only way on earththat living organic matter can be created out of sunlight and except for somebacteria, all living things depend on this energy. Organisms which can create their

own organic material from the sun (or some other source as some bacteria can do)are called autotrophs.

Photosynthetic Equation: H2O + CO2 --> O2 + CHOs

Since plants/algaes are the only organisms that can make organic energy out of thesuns light, they are considered the primary producers in an ecosystem.

Lets say that our incoming photons create 100 kilograms of algae in a pond. Whyalgae since you cant even see it unless there is a lot? Most animal life in a pondeither eats algae directly or eats smaller organisms that eat algae. Thus algae isthe producerand everyone else is a consumer. Consumers which get their energy by

eating (in other words they do not make their own energy) are heterotrophs.Consumers can be plant eaters (herbivores), meat eaters(carnivores), scavengers which eat dead things or detritus (detritivores), or they caneat just about anything (omnivoreshumans, for example, are typically omnivores).

So you have 100 kilograms of algae to pass on to the algae eaters. About 90% of thatavailable energy will be used up by those algae eaters just by their having to live:growth, respiration, energy lost as heat, energy required for movement, etc. So your100 kilograms of algae can produce 10 kilograms of algae eaters. In other words,


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only 10% of the energy produced gets passed on from on trophic level (or level in thefood web) to the next. Thus the more trophic levels you have, the less energy isavailable at the top. This is depicted as the trophic pyramid.

(from: Caduto, 1985)

Food Webs in Specific Wetland Types

1. Salt Marsh


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killifish, and mummichogs, however most marsh fish are transients, typically startingout their life histories in the marsh and then moving on. In fact about 90% of thecommercially important fish and shellfish in the southeast Atlantic and Gulf coastsdepend on marshes.

d. Avian Consumers

This includes many ducks and wading birds. Like the fish, many of these depend onmarshes along their migration routes and are not year round residents.

e. Mammals

Raccoons and muskrats use salt marshes extensively as a food source

2. Mangroves

Because of the salt, there is less variety of producers here, but very high biomassbecause of the constant tidal influx of nutrients. Mangroves themselves are notrequired to live in salt, but they are good at it, so they outcompete anything else.

There is a wide diversity of consumers feed in the mangrove forest, especially filterfeeders and detritivores. Here again it is the detrital web that accounts for most ofthe production (see the figure-the wider arrow indicates the larger input). Barnaclesand oysters filter feed and fiddler crabs scavenge, among lots of other invertebrates,especially juveniles. These juveniles include the commercially important spinylobster, shrimp, mullet, and tarpon. These all provide food for a vast array of wadingbirds.


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(from: Mitsch and Gosselink, 1993)

3. Tidal Freshwater Marshes

a. Producers

Like in a saltmarsh or mangrove, the plants in a tidal freshwater marsh are arrangedin zones according to how wet they like to be. Pondweed, waterweed, and pickerelweed dominate the submerged areas. In the higher areas you have a mixed aquaticcommunity of cattails, wild rice and cordgrass, among others. Since most of thevarieties you find here would grow in just about any marsh, their distribution dependson the flooding pattern and which plants can germinate best (or at all) underwater.

Then theres competition due to shading or chemical defense. Cattails, for example,release chemicals which inhibit seed germination of many other plants.

Algae has less biomass that these vascular plants, but it has a higher turnover rateand since again most production in this wetland is based on the detrital food web, the

algae is very important.

b. Consumers

Here the food web is predominantly detrital with the benthic invertebrates being theimportant link. The smallest eat bacteria and nematodes (microscopic worms) andprobably make up most of the living biomass of the anaerobic sediments. As theseeat bacteria, they package it into bitesize pieces for the next consumers up the line


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which would be amoebas and other plankton which are then eaten by snails, worms,and insect larvae.

i. Nekton

If "benthic" refers to whats on the bottom, and plankton is everything microscopic

and drifting in the water, nekton is everything else in the water, in this case, fish.Typical fish are sunfish, bass, crappies, minnows, shiners, carp, and catfish. You alsoget some estuarine fish such as killifish, mummichogs and anchovies. There arealso anadromous fish (those which live in the ocean but spawn in freshwater) such asshad, herring, and striped bass. Occasionally you find juveniles of saltwater speciessuch as spot, flounder, croaker, and drum. They can physically withstand thefreshwater at these early life stages and presumably take advantage of the relativelack of predators and the food availabilityor they just get washed in.

ii. Birds

Of the wetland types, the tidal freshwater wetlands have the largest and mostdiverse population of birds. Waterfowl, wading birds, ducks, gulls, birds of prey,

shorebirds, plus birds typical of a forest or shrubby area all find satisfactory habitathere.

iii. Reptiles

Population is dominated by turtles, snakes, and alligators.

iv. Mammals

These include deer, rabbits, muskrats, beavers, otters, and nutria (the latter are notfound in coastal Georgia, S.C. or Florida although they are common elsewhere in thesoutheast)

4. Freshwater Marshes

Reed grasses, cattails, rice, sedges, and ragweed are common to most temperatefreshwater marshes, although distribution varies with latitude. These are distributedin zones according to how flooded they get.


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Remember that it is these wetlands that are the most affected by "alien species,"those introduced from elsewhere. The water hyacinth, for example is a problem inthe southeast but on the up side, it is very good at water filtering and then holdingonto the excess nutrients or chemicals. Thus it's often suggested as a valuableaddition to natural wastewater treatment programs. Hydrilla and purple loosestrifeare two other trouble-makers in our area. Note that these are not necessarily "bad"but since they lack natural controls they tend to overtake habitats and outcompetethe natives. This can mean trouble for the consumers that depended on thosenatives.

As with the producers, there is high diversity among the consumers, often becausethese marshes serve as oases in the middle of seas of farmlands.

The decomposers are extremely important here, as is the case with other wetlands,but little is known about them.

The most abundant invertebrates are true flies, including mosquitoes.

With a high diversity of invertebrates there is a high diversity of birds. Note in thefigure below how the birds share the habitat (or in ecological terms, partition theresources). Muskrats are probably the most typical mammal although lots of othersmay pass through.

Fish diversity depends on how big an area we're talking about and how wet it stays.


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5. Peatlands

The dominant plant in a peatland is, of course, moss, especially Sphagnum moss. Itgrows in cushionlike spongy mats with very high water content. Sphagnum moss canhold 15-23 times its dry weight in water. The moss only grows actively at the surface,and the lower layers die off and decompose into peat. Other plants may includeheathers, cranberry, blueberry, some pines, spruce, and tamarack trees.

Remember that these wetlands have the lowest productivity and the lowest nutrientlevels of all the wetlands. For this reason several carnivorous plants are found here.

They get their extra nutrients from insects. These include pitcher plants, sundews,and venus flytraps.

Animal density is fairly low in these wetlands because they are acidic and not mucheats moss. They do serve as trails and shelters for large mammals.

Lots of birds pass through these areas on their migration routes and there are severalthat absolutely depend on them: sandhill cranes, short-eared and great gray owls,sharp-tailed sparrow.

6. Southern Deepwater Swamps

Cypress and tupelo trees dominate these ecosystems and there may or may not bean understory, depending on how dense the canopy is. The more light that getsthrough, the more vegetation beneath. This understory may include red bay, sweetbay, ash, maple, and some pines. There is also always lots of Spanish moss (which isnot actually moss but is an epiphyte related to pineapples-it hangs on the trees butdoes not take anything from them). If the water is constant in these, you also getfloating mats of algae.

There is a high diversity and high biomass o invertebrates which depend on theabundant detritus available. Once again, this is the major source of nutrients for thefood web.


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Reptiles and amphibians are quite diverse because they can adapt to changing floodlevels. These habitats are frequently deep enough and stable enough to supportalligators. If they are that deep and stable, there is probably also a diverse fishpopulation.

7. Riparian Wetlands

The forest you get here depends on how wet it gets. Typically in the south you findred maples, willow, willow oaks, and sweet gum closest to the water. As you moveback from the water, these would give way to other oaks, hickories, and pines.

There is high animal diversity due to the edge effect.

a. predominance of woody plants

sometimes these are the only woods left so they shade the water, stabilizethe bank, and produce leaf litter

b. surface water

this is especially important out west where there is very little water availableabove ground; this directly supports aquatic species plus those that live onthem

c. diversity of habitat

permanently to only occasionally flooded

d. corridors for dispersal and migration

The otter civet weighs 3 - 5 kg (6.6 - 11 lb). It is found in and near streams, rivers andwetlands, eating fish, frogs, crustaceans (e.g. crayfish, crabs, and shrimp).,freshwater molluscs, and to a lesser extent, small mammals, birds and fruit.
http://www.animalinfo.org/glossc.htm#crustaceanhttp://www.animalinfo.org/glossc.htm#crustacean


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The otter civet is found in Peninsular Malaysia, southernThailand, Sumatra and Borneo, and possibly Vietnam.Although widespread it is rare throughout most of itsrange. It is threatened by the loss of wetlands and otheraquatic habitat to development, siltation from mines,persistent pesticides in the food chain, and other kinds of

water pollution.

Mangroves

Mangroves are woody trees or shrubs that grow in mangrove habitats or mangal

(Hogarth, 1999). Mangroves grow only in tropical and subtropical tidelands, which are

frequently inundated with salt water, such as estuaries and marine shorelines.

Mangrove trees form a specific ecological community, denominated as mangroves.

Mangroves can thrive in salt water inundation thanks to their specialized root

structures, as well as their highly adapted and specialised reproductive cycle.

Crucially they have also evolved to be able to excrete salt from their system.Mangrove forests occupy about 17 million hectares of tropical coast worldwide:

across Africa, Australia, Asia and the Americas.

The mangrove ecosystems provide protection against extreme weather events, such

as storm winds and floods, as well as tsunamis. This is due to their capacity to

absorband dissipate the tidal surges that are associated with these events. They also

contribute to the functioning of adjacent ecosystems, including terrestrial wetlands,

peat swamps, salt marshes, sea grass beds and coral reefs.Biodiversity

Rich in biodiversity, mangrove ecosystems provide a habitat for wide varieties of

animal and plant species. According to Hogarth, mangrove areas contain some 54

species of trees in 20 genera, belonging to 16 families that constitute the "truemangroves" species that occur exclusively in mangrove habitats and rarely

elsewhere (Hogarth, 1999).

Moreover, mangroves are home to many kinds of animal species due to the richness

in food and form dynamic ecosystems. Live and decaying mangrove leaves and roots

provide nutrients that nourish plankton, algae, shellfish, fish, crabs and shrimp. Many

of the fish caught commercially in tropical regions reporduce, spend some time in the

mangroves as juveniles or adults or depend on food chains linked to these coastal

ecosystems. Mangroves are also home to many birds and mammals such as

mangrove monkeys in South Asia.

http://www.ppj.gov.my/portal/page?_pageid=311,481604&_dad=portal&_schema=PORTAL

PUTRAJAYA LAKES AND WETLAND
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(An Introduction)

BackgroundPutrajaya is a city planned and built to meet the challenges of the new millennium. Itis A City in a Garden that turns to nature for inspiration, resulting in a landscapedominated by the picturesque Putrajaya Lake. A high standard of lake water quality is

one of the most important factors for the success of this scenic centerpiece, and thesolution was found in simulating yet another gift of nature - with the construction ofPutrajaya Wetland.

Malaysia's new Federal Government Administrative Centre of Putrajaya is not just anew city. It also represents the coming-of-age of Malaysia as a dynamic andprogressive member of the global community committed to the concept ofsustainable development.

Wetland - definitionWetland are defined by the Convention of wetland of International Importance (theRamsar Convention 1971) as; "Land inundated with temporary or permanent water

that is usually slow moving or stationary, shallow, fresh, brackish or saline, where theinundation determines the type and productivity of soils and the plant and animalcommunities".

Constructed wetlandThe role of wetland in water resource management is fast gaining ground resulting inthe construction wetland in most developed countries. Constructed wetland are man-made system that involves altering the existing terrain to simulate wetlandconditions. They primarily attempt to replicate the treatment that has been observedto occur when polluted water enters the natural wetland. These wetland have beenseen to purify water by removing organic compounds and oxidizing ammonia,reducing nitrates and removing phosphorus. The mechanisms are complex and

involve bacterial oxidation, filtration, sedimentation and chemical precipitation.

Most constructed wetland attempt to imitate the ecosystem's biochemical function asfiltration and cleansing agents, followed closely by the hydrological function that iscentred on flood mitigation.

Functions of wetlandThe use of constructed wetland to treat urban surface runoff and remove nutrientsfrom diverse sources in rural catchments has received much attention lately. Thus,wetland are essentially the filtering area, the 'kidneys' of the catchment, interceptingwater flow, trapping sediment and pollutants, removing toxic substances (pesticides,herbicides, metals) and assimilating nutrients and energy derived from the upstreamcatchment area.

Wetland has the ability to filter nutrients from inflowing waters which represent thebase of many food chains that not only start and finish within the wetland but extendbeyond the wetland complex itself. Where there is food there is life, and hencewetland act as breeding grounds, nurseries and homes to numerous plants,invertebrates, frogs, reptiles, fish and waterbirds. In fact, wetland are best known ashabitats for fish and waterbirds.


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Wetland are becoming increasingly popular as ecotourist destinations. Theirbiodiversity, open space, aesthetics and the development of public amenities makethem attractive propositions for passive recreational activities and social pursuit.

It is generally accepted that wetland have the potential to attenuate flooding.Wetland provide retention storage for storm water by spreading the water over a

wide flat area. Wetland vegetation retards surface water flow to varying extentsdepending on the type, density and water depth.

Wetland are a fertile ground for scientific study and research. In fact, there is also agrowing interest in wetland among school children who are beginning to embark on avoyage of discovery of their environment by being introduced to this dynamicecosystem. This may well be the first step in public education of wetland, which arethe collective responsibilities of all users.

Putrajaya LakeThe 400 hectares Putrajaya Lake was created by inundating the valleys of Sungai

Chuau and Sungai Bisa. Construction was undertaken in two phases. The first phaseof approximately 110 hectares involved the construction of a temporary dam acrossSungai Chuau.

The dam was completed in May 1998 and the impoundment of the Phase 1A Lakecommenced in September 1998 and was fully inundated in January 1999. The lakehas been primarily designed to enhance the aesthetic appeal of Putrajaya. It is alsoplanned to be used for sport and recreation as well as a tourist attraction.

Studies of the Putrajaya catchment, however, showed that the water carried elevatedlevel of pollutants derived from upstream sources and outside of the Putrajayadevelopment boundary. Future development of the Sungai Chuau catchment isexpected to increase run-off and pollutant concentration will either be maintained orincreased.

This is expected to result in increased pollutant loadings in Sungai Chuau and SungaiBisa which drain into Putrajaya Lake. As a result, the use of constructed wetland as anatural treatment system was recommended to treat primary upstream inflow to thelake. The wetland is to be complemented by riparian parks and gross pollutant traps.

Putrajaya wetland is the first man-made wetland in Malaysia and one of the largestfully constructed freshwater wetland in the tropics. The 197 hectare project resultedin transforming an oil palm site into wetland ecosystem with the helps of moderntechnology and stringent environmental management methods in design andconstruction.

The wetland straddle the water courses of Sungai Chuau, Sungai Bisa and threetributaries. Their primary function is to ensure that the water entering the lake meetsthe standard set by Perbadanan Putrajaya.

To achieve this, the wetland have been planted with a variety of aquatic plants thatact as a natural filtration system, removing nutrients and pollutants from thecatchment water. They treat natural run-off from the 50.9 sq km Sungai Chuaucatchment.


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In addition to being a water cleansing and filtration system, the wetland also help inflood mitigation, nature conservation, ecotourism, recreation, research and educationand protection against soil erosion. Construction of Putrajaya wetland began in March1997 and was completed in August 1998.

How To Get To Wetland Park PutrajayaFrom Kuala Lumpur, take a Cityliner bus No 868 in front of Sinar Kota near Puduraya.

The bus costs you RM2.70 and you can directly stop at the main entrance of theWetland.

Visiting Hours: Park : Daily 7.00 am - 7.00 pm (including public holidays) Nature Interpretation Centre : Daily 9.00 am - 6.00 pm (including public holidays).

Contact Number : 03-8887 7773

Putrajaya Wetlands is divided into 2 components - Taman Wetland Putrajaya andLake Recreational Centre. Taman Wetland Putrajaya is very much the public face ofthe wetlands and serves as a gateway to Putrajaya Wetlands while the LakeRecreational Centre serves as a water recreational spot.

In his paper Recreational and Educational Opportunities at Putrajaya Wetlands,Richard Lim Szu Ang, Director of Operation, Stagno Vic Sdn Bhd, said both TamanWetland Putrajaya and Lake Recreational Centre offered various recreational andeducational activities and have attracted numerous people who visited the places fordifferent reasons. The most visited spots are the Look-out Tower, Nature Interpretive

Centre and Flamingo Pond.

The Putrajaya Lake & Wetland

The Wetland

The Putrajaya constructed wetland system comprises of six arms with 23 cells asdescribed in Figure 1. All the arms (except of Upper Bisa) eventually discharge to theCentral Wetland, which make the 24 cells in all, before the water flows down into thePutrajaya Lake. They straddle the water courses of Sungai Chuau, Sungai Bisa andthree tributaries. A series of rockfilled weirs was constructed along the six arms ofthe wetland to divide the 24 cells. Although all the six arms are connected, they

differ in size, depths, plant communities and pollutant loads that it is designed tohandle.


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Figure 1 : The Putrajaya Wetland Cells and its location

The basic processes happening in the cell zones are illustrated in Figure 2. Typical longitudinal csection and typical layout of a wetland cell are shown in Figure 3 and Figure 4 respectively.

The design features a multi-cell multi-stage system with flood retention capability to maximize tavailable for colonisation by water plants. The roles of the plants are to intercept pollutants and a root zone where bacteria and microorganisms can flourish to assist in filtering and removing wpollutants.

Figure 2 : Various reactions happening in the wetland cells


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Figure 3: Longitudinal section of a typical wetland cell showing the Zone of Intermittent InundatF1), Wetland Zone (Zone 1, 2 and 3) and the Open Pond

Figure 4 : Typical Layout Of A Wetland Cell

The Putrajaya Wetland cells and its structural components are the keys to the

functioning of the wetlands for cleansing the river water. They are important inmaintaining the broader 'functional capacity' and objectives of the wetlands, whichinclude providing a habitat for local fauna, primarily mammals, water birds, reptiles,amphibians, fish and invertebrates; hydrological modification (by providing flooddetention area and reducing peak discharges and flow velocities) and recreation (thewetlands are used for both passive and active recreation, and parkland for aestheticand recreational value).


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The principle features of the wetland are shown below :

Principal Features of Putrajaya Wetlands (Area in hectares)

Total AreaPlanted

AreaOpenWater

Weirs &Islands

Zone of IntermittentInundation

MaintenanceTracks

197.20 77.70 76.80 9.60 23.70 9.40

Details of the wetland cell structural components and the wetland vegetationspecies and its proper location within the cell are explained and summarized below :

The Wetland Cell Structural Components And Its Function

Zone Component FunctionsInlet Inlet

Energydissipater

Allows water to flow into the wetland cell

Protects the bed of chnnels and inlet andreduces erosion by reducing the energy ofincoming water. May be applicable to anypart of the wetlands where there arepotential erosion problems.

Macrophyte Reed beds

Sedimentationforebay

Waterplants provide support for microbialbiofilms which facilitate nutrienttransformation, organic flocculation,filtration of pollutants, inhancesedimentation and provide oxygen tosediments.

Enhances bacterial decomposition of organicmatter.

Increases biodiversity. Provides a range of habitats for macro and

micro fauna. Provides visual contrast through different

textures, sizes, shapes and colours.

Enhances settling of finer soil and sedimentparticles (that would otherwise pass througha GPT) and associated pollutants such asheavy metals, nutrients and pesticidesadsorbed by the sediments.

Reduces sediment loads to reed bedsensuring higher clarity for effective plantgrowth.

Improves water quality both within anddownstream of the cell and, in turn, theecosystem health.

Open water Open water Allows UV (sunlight) penetration into thewater for disinfection.

Enhances mixing of the water and reducesshort circuiting of flows.

Provides a deep water habitat for fauna,


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refuge during drought, landing and securearea for waterfowl. Meshes into the plantedareas thereby enhancing visual beauty.

Island Provides isolated habitats for birds.

Provides a visual focus for the wetlands.ZII Zone Edge water

plants Create habitat divesity along the shoreline

for invertebrates and wading birds.

Improve water quality.

Physical barrier to human intrusion to thewater.

Outlet ZoneWater levelcontrolstructure

Trash racks

Weir

Allows capture of highly polluted flows for retrievalor recycling.Allows water level control for severalpurposes including:

Operation and maintenance;

Maintaining predetermined water regimesfor greater habitat diversity or to specificallyencourage particular species of flora/fauna;

Manipulation of water level for waterplantestablishment.

Prevent litter and debris entering thecell. Impounds stream flows to create a pool. Setsnormal predetermined designed operating waterlevel in wetland.

The Wetland Vegetation Species And Its Proper Location Within The StructuralComponents Of A Wetland Cell

Wetland

StrucuralComponent

Typical

WaterDepth

Vegetation Typical Species

Shallow Marsh (~0.3m) Shallow marshes can beexpected to have a regulardrying cycle or dry out insome years. Under this typeof hydrological regime adiverse vegetation willdevelop (rushes, sedges andleafy herbs). The actualcomposition of the vegetationcan be expected to change asa response to fluctuations in

water level. Vegetation covercan also vary from sparse todense depending on thespecies and the water cycle.

Eleocharis spiralis, E.variegata, Scleriacyathophora, Carexindica, Cyperus

pulcherrimus,Fimbristylis spp.. Anumber ofdicotyledonous specieswill also occur in thiszone, eg. Clerodendron

spp., Lagerstroemiaspp., Polygonum spp.,Ludwigia spp.

Marsh (~0.6m) As depth of inundation andduration increases vegetationdiversity tends to decrease.Permanently inundatedmarshes with water depths

Scirpus mucronatus,Eleocharis dolcis,Scirpodendron ghaeri,Fuirena umbellata,Lipocarpha chinesis.


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greater than 0.6m arefrequently dominated just afew species which will oftenform a very dense cover ofvegetation. The actualspecies will tend to differ

from marsh to marsh.However the species thattend to dominate thesehabitats are nearly alwaysclonal species with largeunderground rhizomes.

Deep Marsh (~1.0m) As water depth increases thediversity of emergent marshvegetation is further limitedby the size of the plant. Tosurvive in deep water plantsmust be able to grow to abouttwice the water depth. Thevegetation of deep marshesis generally of medium tosparse cover and dominatedby just a few species. Thespecies that tend to dominatethese habitats are alwayslarge clonal species withsubstantial undergroundrhizome systems.

Lepironia articulata,Eleocharisochrostachys,Eleocharis retroreflexa,Phragmites karka,Phragmites australis.

Pond (~ 1.5m) Water depths greater than1.5m will restrict mostemergent aquaticmacrophytes and thus resultin open water zones. Manysubmerged and floatingplants are capable ofcolonising and growing in thistype of environment.Depending on the turbidity itis almost inevitable that thiszone will be colonised bysome aquatic plants. Regularmonitoring of these zones willbe required to ensure anyinvasion of an undesirableweed species is quicklydetected and controlled.

Colonisation of these zonesby acceptable species abenefit as they contribute toenhanced sedimentation andfine particle filtration andprovide habitat for aquaticinvertebrates and fish.

Myriophyllum,Potamogeton,Vallisneria,Nymphaea WeedRisks: Salvinia molesta,Eichhornia crassipes,Pistia stratiotes,Ipomea aquatica.

WetlandStrucural

TypicalWater

Vegetation Typical Species


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Component DepthDeepPond/Sediment

Trap

(~ 2.5m)Water depths greater than2.5m will restrict most rootedemergent and submergedaquatic macrophytesparticularly in constructed

wetlands designed for waterquality control where waterturbidity becomes a limitingfactor. Typically only floatingplants will occur in thesezones. As for ponds, regularmonitoring of these zones willbe required to ensureundesirable weed species aredetected and controlled.

Where these zones arepositioned at the inlet to a

wetland they are the primarysediment traps for thetreatment system so anyvegetation that does happento establish or develop will beregularly disturbed whensediment is being removedfrom the pond.

Myriophyllum,Potamogeton,Vallisneria, Nymphaea.

Weed Risks: The

likelihood of significantsubmerged plantgrowth in these zone isrelatively low but therisk of floating weedinvasion is very high.For exampleSalviniamolesta, Eichhorniacrassipes, Pistiastratiotes, Ipomeaaquatica.

WetlandFringing Zones

The edges and surroundingarea of wetlands typicallyexperience large variations ininundation depth, frequencyand duration. The zone

immediately above and belownormal water level usuallyexperiences the greatestvariation. This zonecommonly supports fringingmarsh and swamp vegetationadapted to regular but shortduration inundation. Withincreasing elevationinundation frequency andduration in particulardecreases. Under these lessrestrictive conditions for plantgrowth a range of woodyvegetation can develop.

Typical examples are riparianand floodplain swamp forests.

FringingMarsh/Swamp

aboveNWL

(~ 0.3m)

Hydrologically this zone hassimilar inundation depths asthe Shallow Marsh zone butnormally increased frequencyand reduced duration. As aresult there are a very great

This zone can support agreat number ofspecies and suitableplants can be selectedfrom the followinggenera, eg. Cyperus,


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number of plants that canoccur in this zone rangingfrom sedges and rushesthrough leafy herbs to woodyshrubs and trees.

Eleocharis, Limnophila,Ludwigia, Polygonum,Pandanus, Eugenia,Barringtonia.

Swamp Forest above

NWL

(~ 0-1.5m)

Hydrologically this zone isvery well watered withregular inundation periodsbut is also regularly drainedwell enough to support largewoody vegetation. Tropicalswamp forests are typicallyvery diverse systems bothfloristically and structurallyand dominated by small tomedium sized trees.

This zone can support a

great number ofspecies and suitableplants can be selectedfrom the followinggenera, Eugenia,Dipterocarpus,Fagraea, Ficus, Ixora,Lithocarpus, Litsea,Pandanus, Podocarpus,Shorea, Tarenna,Tristania,

Xanthophyllum.

The Putrajaya Lake

The lake is at the southern part of the wetland. About 60% of the lake water flowfrom the wetland and the remaining 40% is the direct discharge from borderingpromenade. The 20 m width promenade is the buffer feature along the lakeshorelines. The water surface area of the whole lake is about 400 hectares. The totalvolume of the whole lake water is about 23.5 million cubic meters and the waterdepth is in the range of 3 to 14 meters. The lake has been planned to cater for multi-functional uses, including recreation, fishing, water sports and water transport. Thelake and its foreshores also form Putrajaya's most popular resource for informalrecreation as a waterfront city.

The principle features of the lake are shown below.

Principal Features of Putrajaya Lake

CatchmentsArea

WaterLevel

SurfaceArea

StorageVolume

AverageDepth

AverageCatchments

Inflow

AverageRetention

Time

50.90 KM2RL 21.00

M

400 ha

(4 K M2 )

23.50mil. M3

6.60 M200 million

liters132 days


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Putra Wetlands

Covering a total area of 335ha, the wetland environment comprises Taman Wetland(138ha) and the wetland areas (197ha). One of the most popular tourist attractions inPutrajaya, the wetlands consist of 24 wetland cells built along the arms of the Chuaand Bisa rivers.

Marshes and swamps were developed in there cells by transplanting more than 70species of wetland plants form the Putrajaya Wetland Nursery. Twenty-four species ofindigenous fish were later introduced into the wetland cells to enhance theirbiological diversity.

A good starting point to explore Putrajaya Wetlands is to visit Taman Wetland. As thegateway to the wetlands area, Taman Wetland house a Nature Interpretation Centreand a 25 meter high look-out tower which offers a bird's eye view of Putrajaya. Withinthe park, there are two marked trails with interpretative boards, a flamingo pond,picnic areas and other public amenities.

Taman Wetland is also a wildlife sanctuary, attracting a wide variety of animals to the

combined terrestrial-aquatic wetland environment. Several species of localmarshland birds and water birds including the Little Egret, the Little Green Heron andCinnamon Bittern, and migratory birds form Northern Hemisphere have been spottedthere. A pair of binoculars will come in handy for bird watching. Visitors to the parkcan also enjoy a leisurely walk, jog or cycle along its bicycle track.Putra Wetland

In the Nature Interpretation Centre, there is a souvenir shop, a wetland diorama,wetland handicraft displays, an AV room and Wetland Caf. The Centre, being thefocal point for public education on ecotourism, provides information about thewetland plant bed filtration system, conservation of wetland habitats and alsofocuses on the uses of wetland products.

Putrajaya Wetlands, believed to be the largest constructed freshwater wetlands inthe tropics, is the first one of its kind in Malaysia. Where geology, hydrology andbiology have created natural wetlands, the Putrajaya Wetland carved out from rubberand oil palm plantations is the result of human ingenuity and technology.

Read more: Putrajaya Wetlands - Kuala Lumpur Hotels & TravelGuidehttp://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7

Putrajaya Wetlands in Putrajaya, Malaysia is believed to be the largest constructed

freshwater wetlands in the tropics .It has a total area of 200 hactares (3.35 km).

Putrajaya Wetlands consists of 24 wetland cells, Wetlands Park (Taman Wetland) and

the other Wetlands areas. The Wetland now is also a wildlife sanctuary which attracts

a huge variety of animals to the combined terrestrial-aquatic wetland environment.
http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://en.wikipedia.org/wiki/Putrajayahttp://en.wikipedia.org/wiki/Malaysiahttp://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://www.kuala-lumpur.ws/putrajaya/wetland.htm#ixzz1Hmwk1Ok7http://en.wikipedia.org/wiki/Putrajayahttp://en.wikipedia.org/wiki/Malaysia


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Several species of localmarshland birds and water birds including the Little Egret,

the Little Green Heron and Cinnamon Bittern, and migratory birds form Northern

Hemisphere have been spotted there. Binoculars will come in handy for bird

watching. The visitors can also enjoy a leisurely walk, jog or cycle along its bicycle

track.

The Little Egret (Egretta garzetta) is a small white heron. It is the Old Worldcounterpart to the very similar New WorldSnowy Egret.

Little Egrets eat fish, insects, amphibians, crustaceans, and reptiles. They stalk theirprey in shallow water, often running with raised wings or shuffling its feet to disturbsmall fish. They may also stand still and wait to ambush prey.

The Green Heron (Butorides virescens) is a smallheron ofNorth andCentral America.It was long considered conspecific with its sister species theStriated Heron (Butoridesstriata), and together they were called "Green-backed Heron". Birds of thenominatesubspecies(no matter which taxonomicarrangement is preferred) are extremely rarevagrants to western Europe; individuals from the Pacific coast of North America maysimilarly stray as far as Hawaii.[2]

The habitat of the Green Heron is small wetlands in low-lying areas. The species ismost conspicuous during dusk and dawn, and if anything these birdsarenocturnalrather than diurnal, preferring to retreate to sheltered areas indaytime. They feed actively during the day, however, if hungry or provisioning young.
http://en.wikipedia.org/wiki/Marshlandhttp://en.wikipedia.org/wiki/Marshlandhttp://en.wikipedia.org/wiki/Little_Egrethttp://en.wikipedia.org/wiki/Green_Heronhttp://en.wikipedia.org/wiki/Cinnamon_Bitternhttp://en.wikipedia.org/wiki/Heronhttp://en.wikipedia.org/wiki/Snowy_Egrethttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Amphibianshttp://en.wikipedia.org/wiki/Crustaceanhttp://en.wikipedia.org/wiki/Reptileshttp://en.wikipedia.org/wiki/Heronhttp://en.wikipedia.org/wiki/North_Americahttp://en.wikipedia.org/wiki/Central_Americahttp://en.wikipedia.org/wiki/Central_Americahttp://en.wikipedia.org/wiki/Conspecifichttp://en.wikipedia.org/wiki/Sister_specieshttp://en.wikipedia.org/wiki/Striated_Heronhttp://en.wikipedia.org/wiki/Green-backed_Heronhttp://en.wikipedia.org/wiki/Nominate_subspecieshttp://en.wikipedia.org/wiki/Nominate_subspecieshttp://en.wikipedia.org/wiki/Nominate_subspecieshttp://en.wikipedia.org/wiki/Taxonomichttp://en.wikipedia.org/wiki/Europehttp://en.wikipedia.org/wiki/Europehttp://en.wikipedia.org/wiki/Pacifichttp://en.wikipedia.org/wiki/Hawaiihttp://en.wikipedia.org/wiki/Hawaiihttp://en.wikipedia.org/wiki/Green_Heron#cite_note-hbw-clo-adw-1http://en.wikipedia.org/wiki/Habitathttp://en.wikipedia.org/wiki/Nocturnalhttp://en.wikipedia.org/wiki/Nocturnalhttp://en.wikipedia.org/wiki/Nocturnalhttp://en.wikipedia.org/wiki/Diurnalityhttp://en.wikipedia.org/wiki/Marshlandhttp://en.wikipedia.org/wiki/Little_Egrethttp://en.wikipedia.org/wiki/Green_Heronhttp://en.wikipedia.org/wiki/Cinnamon_Bitternhttp://en.wikipedia.org/wiki/Heronhttp://en.wikipedia.org/wiki/Snowy_Egrethttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Amphibianshttp://en.wikipedia.org/wiki/Crustaceanhttp://en.wikipedia.org/wiki/Reptileshttp://en.wikipedia.org/wiki/Heronhttp://en.wikipedia.org/wiki/North_Americahttp://en.wikipedia.org/wiki/Central_Americahttp://en.wikipedia.org/wiki/Conspecifichttp://en.wikipedia.org/wiki/Sister_specieshttp://en.wikipedia.org/wiki/Striated_Heronhttp://en.wikipedia.org/wiki/Green-backed_Heronhttp://en.wikipedia.org/wiki/Nominate_subspecieshttp://en.wikipedia.org/wiki/Nominate_subspecieshttp://en.wikipedia.org/wiki/Taxonomichttp://en.wikipedia.org/wiki/Europehttp://en.wikipedia.org/wiki/Pacifichttp://en.wikipedia.org/wiki/Hawaiihttp://en.wikipedia.org/wiki/Green_Heron#cite_note-hbw-clo-adw-1http://en.wikipedia.org/wiki/Habitathttp://en.wikipedia.org/wiki/Nocturnalhttp://en.wikipedia.org/wiki/Diurnality


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Shore-living individuals adapt to the rhythm of the tides. They mainly eat small fish,frogs and aquatic arthropods, but may take any invertebrate orvertebrate prey theycan catch, including such animals likeleechesand mice. Green Herons are intolerantof other birds - including conspecifics - when feeding and are not seen to forage ingroups. They typically stand still on shore or in shallow water or perch upon branchesand await prey. Sometimes they drop food, insects, or other small objects on the

water's surface to attract fish, making them one of the few known tool-using species.They are able to hover briefly to catch prey.[2]

The Cinnamon Bittern or Chestnut Bittern (Ixobrychus cinnamomeus) is a

small bittern. It is of Old World origins, breeding in tropical Asiafrom Pakistan to Sri

Lanka east toChina andIndonesia. It is mainly resident, but some northernbirds migrateshort distances.

This is a small species at 38 cm length, with a short neck and longish bill. The male is

uniformly cinnamon above and buff below. The female's back and crown are brown,

and the juvenile is like the female but heavily streaked brown below.

When surprised on its nest or concerned, it assumes the characteristic attitude

ofbitterns, aptly termed the On-Guard. The neck is stretched perpendicularly, bill

pointing skyward, while the bird freezes, becoming astonishingly obliterated amongst

its reedy environment.[2]

Their breeding habitat is reedbeds. They nest on platforms of reeds in shrubs. 4-6

eggs are laid. They can be difficult to see, given theirskulking lifestyle and reedbed

habitat, but tend to emerge at dusk, when they can be seen creeping almost cat-like

in search offrogs.
http://en.wikipedia.org/wiki/Arthropodhttp://en.wikipedia.org/wiki/Invertebratehttp://en.wikipedia.org/wiki/Vertebratehttp://en.wikipedia.org/wiki/Leechhttp://en.wikipedia.org/wiki/Leechhttp://en.wikipedia.org/wiki/Conspecifichttp://en.wikipedia.org/wiki/Category:Tool-using_specieshttp://en.wikipedia.org/wiki/Green_Heron#cite_note-hbw-clo-adw-1http://en.wikipedia.org/wiki/Bitternhttp://en.wikipedia.org/wiki/Asiahttp://en.wikipedia.org/wiki/Asiahttp://en.wikipedia.org/wiki/Pakistanhttp://en.wikipedia.org/wiki/Sri_Lankahttp://en.wikipedia.org/wiki/Sri_Lankahttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/Indonesiahttp://en.wikipedia.org/wiki/Indonesiahttp://en.wikipedia.org/wiki/Bird_migrationhttp://en.wikipedia.org/wiki/Bird_migrationhttp://en.wikipedia.org/wiki/Bitternhttp://en.wikipedia.org/wiki/Cinnamon_Bittern#cite_note-ali-daniel-1http://en.wikipedia.org/wiki/Skulkinghttp://en.wikipedia.org/wiki/Skulkinghttp://en.wikipedia.org/wiki/Froghttp://en.wikipedia.org/wiki/Arthropodhttp://en.wikipedia.org/wiki/Invertebratehttp://en.wikipedia.org/wiki/Vertebratehttp://en.wikipedia.org/wiki/Leechhttp://en.wikipedia.org/wiki/Conspecifichttp://en.wikipedia.org/wiki/Category:Tool-using_specieshttp://en.wikipedia.org/wiki/Green_Heron#cite_note-hbw-clo-adw-1http://en.wikipedia.org/wiki/Bitternhttp://en.wikipedia.org/wiki/Asiahttp://en.wikipedia.org/wiki/Pakistanhttp://en.wikipedia.org/wiki/Sri_Lankahttp://en.wikipedia.org/wiki/Sri_Lankahttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/Indonesiahttp://en.wikipedia.org/wiki/Bird_migrationhttp://en.wikipedia.org/wiki/Bitternhttp://en.wikipedia.org/wiki/Cinnamon_Bittern#cite_note-ali-daniel-1http://en.wikipedia.org/wiki/Skulkinghttp://en.wikipedia.org/wiki/Frog


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Cinnamon Bitterns feed on insects, fish and amphibians.

[edit]
http://en.wikipedia.org/wiki/Insecthttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Amphibiahttp://en.wikipedia.org/w/index.php?title=Cinnamon_Bittern&action=edit&section=1http://en.wikipedia.org/wiki/Insecthttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Amphibiahttp://en.wikipedia.org/w/index.php?title=Cinnamon_Bittern&action=edit&section=1

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Food Webs in Wetlands

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