FW ecosystem z2 edited.pptx includes lentic and lotic ecosystem

Fresh water ecosystem is the type of aquatic ecosystem.. it includes lentic and lotic type of ecosystem.. it refers to the standing and flowing water systems..
All the rivers, pond, lake, stream etc can be studies in this type of ecosystem..hhiikbwft irak pain Betsey niddi kai Barbi nagti kicks jkd body whjhfcvbhusiiwihwbnnsmsksjttywiikkknnnnnnnnnnnnnnndkjwiwiollklllll

1. Fresh water habitat By Miss Shalini Rajput

2. Lentic Ecosystems Lentic comes from the Latin word lenis, meaning "calm“ These are stagnant water ecosystems that formed as a result of: Glacial erosion, when basins carved in the bedrock are filled with water as the glaciers retreated Geologic events such as mountain building or rock displacement create water filled basins Sunken craters (calderas) of extinct volcanoes can form lakes Man's activities Stagnant water ecosystems are expected to change over time, at a rate more or less inversely proportional to their size and depth. Common examples include lakes and ponds. Generally speaking, species diversity is low in freshwater communities, compared to marine or tropical ecosystem types.

3. Zoning and Stratification Zoning and distinctive stratification are characteristic features of large lakes and ponds. Zones based on Light Penetration 1. Littoral Zone (Zone of Emergent Vegetation, Zone of Floating Vegetation, Zone of Submersed Vegetation) 2. Limnetic Zone 3. Profundal Zone 4. Benthic Zone Zones based on Temperature Stratification 1. Epilimnion 2. Metalimnion (Thermocline) 3. Hypolimnion

4. Littoral Zone The littoral zone is the region near the shore where sufficient light reaches the bottom to support rooted plants. In many shallow lakes and ponds, this zone may extend completely across the basin. • There are usually distinct community. 3 Regions of the Littoral Zone: Zone of Emergent Vegetation Zone of Floating Vegetation Zone of Submersed Vegetation

5. Regions of the Littoral Zone 1. Zone of Emergent Vegetation Near the shoreline. This region is usually dominated by grasses, rushes, and sedges.. Cattail and arrowhead are common examples.The plants of the emergent zone utilize atmospheric carbon dioxide and oxygen.. Minerals and water however are derived from the lake substrate.. Emergent macrophytes are similar to terrestrial plants except that they are always rooted in deoxygenated mud rather than well-aerated soil. Roots, leaves, and stems of emergent macrophytes contain large air-filled spaces along which oxygen can travel to relieve the shortage (of oxygen) in the roots.

6. Regions of the Littoral Zone 2. Zone of Floating Vegetation As depth increases, a transition to plants with long stems or petioles, and floating leaves represents a transition from one environment to another and is known as zone of succession ( hydrosere ). This community includes water lilies (Nymphaea) and pond weeds ( Potamogeton ). Plants in this zone possess localized masses of spongy tissue to aid in buoyancy. Stomata are restricted primarily to the upper surface of the leaves where they have access to atmospheric gases. Absorption of ions takes place on theunderneath side of the leaf.

7. Regions of the Littoral Zone 3.Zone of Submersed Vegetation The innermost region of the littoral zone. These plants may be considered to be truly aquatic. Wholly submerged plants cannot obtain oxygen from the air and must extract all gases they need from water. They have very thin leaves and much of the oxygen released during photosynthesis goes to alleviate the shortage in the roots.Prominent submersed vegetation include stonewort ( Chara ), hornwort ( Ceratophyllum ), milfoil ( Myriophyllum ), waterweed (Elodea), and the introduced plant Hydrilla .

8. Other Flora within the Littoral Zone:. There are usually a number of non-rooted free-floating hydrophytes in this zone. Free-floating plants derive their nutrients from the water. Among the plants that float on the surface in sheltered places, the smallest are duckweeds ( Lemna ), and the largest include water hyacinth ( Eichhornia ) and floating fern ( Salvinia ).

9. Fauna in the Littoral Zone Animals in the littoral zone mostly live on the surface of leaves or stems or burrow among the plant roots. The only substrate for animals in this zone is rocks and the only food is algae either present in the water or attached to the rocks, and the detritus that is lodged among the stones. The advantage in this zone is that oxygen is never likely to be limited as water is constantly dissolving more oxygen from the air. Pond snails are a conspicuous group of littoral zone animals along with many species of freshwater crustacea (shrimps and crabs). Littoral zone provides habitat for insects like dragonflies ( Odonata ), mayflies ( Ephemeroptera ), stoneflies ( Plecoptera ), caddis flies ( Trichoptera ) and midges ( Diptera ).

10. Limnetic Zone Is the area of open water bounded by the littoral region. Trophogenic Zone - main photosynthetic zone which possesses sufficient sunlight for photosynthesis to exceed respiration (P > R). It is dominated by planktons and nektons which are distinguished based on their swimming ability. Planktons are suspended in water Nektons are active swimmers Neuston are organisms that attaches to the underside of the surface film of water through surface tension. Most birds feeding in this zone are fish eaters and either dive for their prey or catch it close to the surface.Birds (like geese and duck) are also attracted to these zones for refuge from terrestrial predators.

11. Profundal Zone Layer of deep, open water where it is too dark for photosynthesis. Tropholytic Zone - region where respiration is greater than photosynthesis (P < R). This typically contains the colder, darker, poorer oxygenated deep water of a lake. Relatively few organisms are adapted to the deeper profundal regions. The border between the limnetic zone and profundal zone is the light compensation point (light compensation level), the depth at which light intensity results in equal rates of photosynthesis and respiration (P = R).

12. Benthic Zone Deepest zone where nutrients come from dead organic matter from the upper zones or from sediments washed into lake. Benthic primary producers include cyanobacteria, and all higher taxa of eukaryotic algae. The larger inhabitants of this zone are mostly worms, larvae of chironomid flies, and molluscs . In addition there are numerous smaller animals like nematode and ostracods . Worms mostly have haemoglobin in the blood, which help trap oxygen, an advantage, as the benthic community suffers from lack of oxygen. Chironomids are very characteristic lakeside inhabitants, typical of many lake insects, with larvae living and growing in the water. The larvae are essential food for many fish and ducks. Bivalve Molluscs are important components of the benthic fauna. Mussels are important filter feeders and are usually the largest members of the lake community to feed directly on the smallest algae.

13. Zones based on Temperature Stratification. Epilimnion - The uppermost region of warm circulating water. Metalimnion The zone of rapid temperature change in between the two regions. The region of fluctuating temperature within the metalimnion is called a thermocline.The thermocline acts as a barrier between the warmer water above and the colder water below. Hypolimnion The deeper, colder, and relatively undisturbed bottom waters.This region corresponds roughly to the profundal zone.