Pond Ecosystem

Components of Pond Ecosystem

Ponds are the small bodies of water which have very less or on currents. Ponds have a great deal of vegetation which increases with the age of ponds .They possess little water in the centre .The deepth of water varies from few in ches to about 10 metre or some times more. Ponds are not stratified as the farce of wind keeps the entire mass of water in circulation .It result in uniform distribution of O₂, CO₂ and temperature.

Though there is no stratification of pond, but some ecologists classified pond into several Zones—

On the basis of water depth:

On the basis of water depth and types of organisms, ponds are classified in to several zones –

(a) Littaral zone : Shallow water near the share , forms the littoral zone. It contains upper worm and oxggen reach circulating water layer which is called , epilimnior . It contains rooted vegetation .

(b) Sub littoral zone: It extends from rooted veretation to the non circulating cold water with comperatively poor oxygen zone. This layer is very rare in pond but sometimes found in extremely deep pond.

(c) Limnetic zone: Limnetic zone is the open water zone away from the shore. It is the zone upto the depth of effective light penetration where rate of photosynthesis is equal to the rate of respiration .

(d)Profundal zone: It is the deep water area beneath the limnetic zone and beyond the depth of effective light penetration.

Components of pond :

Like other ecosystem, components of pond ecosystem is categorized into two main components

(i) Abiotic or constructive components and (ii)biotic and assimilative or functional conponents .

(i) Abiotic component :

The abiotic components comprise water, oxygen, Phasphorus, nitrogen, calcium, amino acid, humic acid, soil etc. Producers take them or use them in a small amount in soluble form. Abiotic components are also called constructive component of ecosystem.

(ii)Biotic component :

In a pond , different organisms maintain the stability of ecosystem. However , the components of different zone are of different types .

(a)Biota of littaral zone :

Littaral zone of a pond contains maximum oxygen content and other natural resources and sufficient light and temperature. This zone is also known as productive zone as it reached in pedonic flora .At the shore proper ,vegetations are the emergent vegetation which remain firmly rooted in the shore substratum. But their tops with thin chlorophyll bearing regions are exposed. Certain rooted emerged plants are Ranunculus, Monochoria , Cyperus and Rumex Interspersed with these plants, there are some plants which contain comperatively more chlorophyll bearing structure like Typha, Scirpus, Sagittaria, etc. Slightly deeper , the rooted are found which have broad floating leaves, eg. Nymphaea, Nelumbo, Aponogeton and Marsilea. Further deeper submerged plant of pond includes Vallisneria, Isoetes, Hydrila, Chara, Elodea .

Except the above mention producer, littaral zone also contains some phytoplanktons, Diatoms (Navicula, Cyclotella ); blue green algae (Microcystic , Oscillatoria ); green algae (Cosmarium).

Littoral zone contains a huge concentration of animals. They feed on plants and animals of lower trophic level. In this zone, all the types of consumers i.e., primary consumers, secondary consumers and tertiary consumers are found. Some consumers are distributed in recognizable communities like Nymph, Dragon fly, Crey-fish, fsopod, worms, snails etc. Some of the animals like in on plants and other objects projecting upon the bottom. These includes protozoans such as Stenor, Vorticella and some leach like animal Glossophonic .

Except them, some crustaceans such as Cyclops, Daphnia etc., are also very common consumer of the pond. Some other animal which feeds on the smaller plants like Paramecium, Euglena, Ranadra, Corixa and larva of Culex. This animals are eaten by some faunal component of littoral zone like frogs, snakes, some crabs and some large fishes .

(b)Biota of limnetic zone:

Limnetic zone is the region of rapid variation with the water level, temperature and oxgen content varing from time to time. Generally it contains, optimum vegetation as it is characterized by P/R= 1 variour protozoans and phytoplanktons are the common consumer and producer respectively. The common producer organism are Volvox, Euglena, etc. Common primary consumers are Rotaria, Philodina, Snakes etc. Some vertibrates like frogs, fishes and some crabs act as secondary consumer.

Profundal zone is the zone where oxygen concentration and light penetration is extremely low. Due to this abiotic conditions, no aerobic organism colonises on this zone. Thus the zone contains only some detrivorous organism like anaerobic bacteria and saprophytic fungi. The detritus components obtain their energy from the rains out of the limnetic zone. The organisms obtain the energy by chemical degeneration. However some large fishes spend a sufficient time in this zone like Clarias, Batrachus, Heteropnenstis, fossilis etc .

Thus it is clear that four components maintain the stability of pond ecosystem i.e., abiotic components, producers, consumers, decomposer. Producer produces food by using abiotic components and the remnants of decomposer’s chemical degradation. Producer provides food to consumers of different zones of pond where as their dead body and dead remaining provides energy to the decomposers. The consumers are also serve as energy material for decomposers after their death .Imbalance or lack of co-operation in any stage of ecosystem completely destroy the whole pond ecosystem.