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coastal wetland and its thereats

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Wetlands provide important ecosystem services but face many threats. On-site threats include draining wetlands for agriculture, dumping waste, and pollution from nearby activities. Off-site threats involve upstream deforestation, dams altering water flows, and pollution from distant sources. A key threat is conversion to aquaculture through draining or filling wetlands. Wetlands are drained and filled to make way for shrimp or fish farms, eliminating natural habitat.

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COASTAL WETLANDS & ITS THREATS shaik umme salma Aem MFK 1710
Wetlands are... A wetland is a distinct ecosystem that is inundated by water, either permanently or seasonally, where oxygen-free processes prevail. The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil.
Under the Ramsar international wetland conservation treaty, wetlands are defined as follows: Article 1.1: "...wetlands are areas of marsh, fen, peat land or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six meters." Article 2.1: "[Wetlands] may incorporate riparian and coastal zones adjacent to the wetlands, and islands or bodies of marine water deeper than six meters at low tide lying within the wetlands." Ramsar Convention definition @1971
Wetlands – lands covered with water all or part of a year Hydric (saturated) soils – saturated long enough to create an anaerobic state in the soil horizon Hydrophytic plants – adapted to thrive in wetlands despite the stresses of an anaerobic and flooded environment Hydrologic regime – dynamic or dominant presence of water
General Types of Aquatic Macrophytes Submergent – Plants that grow entirely under water. Most are rooted at the bottom and some may have flowers that extend above the water surface. Floating-leaved – Plants rooted to the bottom with leaves that float on the water surface. Flowers are normally above water. Free Floating – Plants not rooted to the bottom and float on the surface. Emergent – herbaceous or woody plants that have the majority of their vegetative parts above the surface of the water.
Plant zone according to water depth in a freshwater marsh
Hydrilla Coontail Parrotfeather
Floating-Leaved Plants
Free Floating Plants
Emergent Plants
Benefits of Aquatic Plants Primary Production Wildlife Food Oxygen Production Shelter Protection from predation for small fish Fish Spawning Several fish attach eggs to aquatic macrophytes Some fish build nests in plant beds Water Treatment Wetland plants are very effective at removing nitrogen and phosphorous from polluted waters
Submerged macrophytes can provide shelter for young fish as well as house an abundant food supply.
Some fish will attach their eggs to aquatic vegetation. Alligators also build nests from vegetation.
Wetlands of Rajasthan Name Designated Area(km2) Keoladeo National Park 01/10/1981 28.73 Sambhar Lake 23/03/1990 240
Land birds  Among land birds are a rich assortment consisting of warblers, babblers, bee- eaters, bulbuls, buntings, chats, partridges and quails. Grey hornbill and Marshall's iora are also present.  There are many birds of prey including the osprey, peregrine, Pallas' sea eagle, short-toed eagle, etc..  Greater spotted eagle has recently been recorded breeding here, a new breeding record for the species in India.
The Sambhar Lake, India's largest inland salt lake, a bowl shape lake encircles historical Sambhar Lake Town located 96 km south west of the city of Jaipur (Northwest India) and 64 km north east ofAjmer.
Economic importance It is India's largest saline lake and is the source of most of Rajasthan's salt production. It produces 196,000 tones of clean salt every year, which equates to around 9% of India's salt production. Salt is produced by evaporation process of brine and is mostly managed by Sambhar Salts Ltd.(SSL), a joint venture of the Hindustan Salts Ltd. and the state government. Ecological importance Sambhar has been designated as a Ramsar site (recognized wetland of international importance) because the wetland is a key wintering area for tens of thousands of flamingos and other birds that migrate from northernAsia. The specialized algae and bacteria growing in the lake provide striking water colors and support the lake ecology that, in turn, sustains the migrating waterfowl.
VID-20190111-WA0010.mp4
CAUSES Natural threats Human threats • On-site • Off-site
Natural threats : On site/Off site •Global warming, climate change : temperature rise, shifting rainfallpatterns/distribution/intensity •Sea level rise •Extremes : droughts, floods •Storms, winds, waves, currents, tsunami •Landslides, subsidence, erosion, earthquakes, volcanoes •Biotic effects : floral decay, diseases •Others ………….
Human threats : On site On site Drainage for agriculture, forestry •Control of mosquitoes/diseases •Dredging, channelization •Filling for solid waste disposal, commercial, residential, industrial areas •Conversion for aquaculture and other land uses •Discharges of pesticides, herbicides, nutrients, sediment, toxicants from domestic sewage, agricultural, aquaculture & livestock runoff, industries •Inappropriate restoration techniques
• Mining of wetland soils for peat, coal, clay, sand, gravel, minerals, gemstones, phosphate and other materials •Introduction of alien invasive species •Groundwater abstraction •Non-wise use activities / patterns, illegal hunting, inappropriate fishing practices, over-exploitation of wetland resource •Changing life style, cultural perception and behavior towards wetland conservation •Tourism •Burning, fires •Construction of roads, dikes, dams, etc. •Others ……………..
Human actions : Off site • Deforestation, degradation of upper-watershed •Inappropriate land uses in upper-watershed •Sediment diversion by dams, deep channels •Hydrological alterations by roads, barriers encircling wetlands •Pollution of all forms e.g. from industries, agriculture, communities, urbans, etc. •Over-extraction of groundwater •Minings(inland & off-shore), sand pumping, mineral, oil/gas extraction subsidence •Mega-projects, infrastructures development e.g. dams, roads, power plants, etc. •Population growth pressure on wetlands
CONVERSION TO AQUACULTURE
coastal wetland and its thereats
coastal wetland and its thereats

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coastal wetland and its thereats

  • 1. COASTAL WETLANDS & ITS THREATS shaik umme salma Aem MFK 1710
  • 2. Wetlands are... A wetland is a distinct ecosystem that is inundated by water, either permanently or seasonally, where oxygen-free processes prevail. The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil.
  • 3. Under the Ramsar international wetland conservation treaty, wetlands are defined as follows: Article 1.1: "...wetlands are areas of marsh, fen, peat land or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six meters." Article 2.1: "[Wetlands] may incorporate riparian and coastal zones adjacent to the wetlands, and islands or bodies of marine water deeper than six meters at low tide lying within the wetlands." Ramsar Convention definition @1971
  • 4. Wetlands – lands covered with water all or part of a year Hydric (saturated) soils – saturated long enough to create an anaerobic state in the soil horizon Hydrophytic plants – adapted to thrive in wetlands despite the stresses of an anaerobic and flooded environment Hydrologic regime – dynamic or dominant presence of water
  • 5. General Types of Aquatic Macrophytes Submergent – Plants that grow entirely under water. Most are rooted at the bottom and some may have flowers that extend above the water surface. Floating-leaved – Plants rooted to the bottom with leaves that float on the water surface. Flowers are normally above water. Free Floating – Plants not rooted to the bottom and float on the surface. Emergent – herbaceous or woody plants that have the majority of their vegetative parts above the surface of the water.
  • 6. Plant zone according to water depth in a freshwater marsh
  • 11. Benefits of Aquatic Plants Primary Production Wildlife Food Oxygen Production Shelter Protection from predation for small fish Fish Spawning Several fish attach eggs to aquatic macrophytes Some fish build nests in plant beds Water Treatment Wetland plants are very effective at removing nitrogen and phosphorous from polluted waters
  • 12. Submerged macrophytes can provide shelter for young fish as well as house an abundant food supply.
  • 13. Some fish will attach their eggs to aquatic vegetation. Alligators also build nests from vegetation.
  • 14. Wetlands of Rajasthan Name Designated Area(km2) Keoladeo National Park 01/10/1981 28.73 Sambhar Lake 23/03/1990 240
  • 15. Land birds  Among land birds are a rich assortment consisting of warblers, babblers, bee- eaters, bulbuls, buntings, chats, partridges and quails. Grey hornbill and Marshall's iora are also present.  There are many birds of prey including the osprey, peregrine, Pallas' sea eagle, short-toed eagle, etc..  Greater spotted eagle has recently been recorded breeding here, a new breeding record for the species in India.
  • 16. The Sambhar Lake, India's largest inland salt lake, a bowl shape lake encircles historical Sambhar Lake Town located 96 km south west of the city of Jaipur (Northwest India) and 64 km north east ofAjmer.
  • 17. Economic importance It is India's largest saline lake and is the source of most of Rajasthan's salt production. It produces 196,000 tones of clean salt every year, which equates to around 9% of India's salt production. Salt is produced by evaporation process of brine and is mostly managed by Sambhar Salts Ltd.(SSL), a joint venture of the Hindustan Salts Ltd. and the state government. Ecological importance Sambhar has been designated as a Ramsar site (recognized wetland of international importance) because the wetland is a key wintering area for tens of thousands of flamingos and other birds that migrate from northernAsia. The specialized algae and bacteria growing in the lake provide striking water colors and support the lake ecology that, in turn, sustains the migrating waterfowl.
  • 20. Natural threats : On site/Off site •Global warming, climate change : temperature rise, shifting rainfallpatterns/distribution/intensity •Sea level rise •Extremes : droughts, floods •Storms, winds, waves, currents, tsunami •Landslides, subsidence, erosion, earthquakes, volcanoes •Biotic effects : floral decay, diseases •Others ………….
  • 21. Human threats : On site On site Drainage for agriculture, forestry •Control of mosquitoes/diseases •Dredging, channelization •Filling for solid waste disposal, commercial, residential, industrial areas •Conversion for aquaculture and other land uses •Discharges of pesticides, herbicides, nutrients, sediment, toxicants from domestic sewage, agricultural, aquaculture & livestock runoff, industries •Inappropriate restoration techniques
  • 22. • Mining of wetland soils for peat, coal, clay, sand, gravel, minerals, gemstones, phosphate and other materials •Introduction of alien invasive species •Groundwater abstraction •Non-wise use activities / patterns, illegal hunting, inappropriate fishing practices, over-exploitation of wetland resource •Changing life style, cultural perception and behavior towards wetland conservation •Tourism •Burning, fires •Construction of roads, dikes, dams, etc. •Others ……………..
  • 23. Human actions : Off site • Deforestation, degradation of upper-watershed •Inappropriate land uses in upper-watershed •Sediment diversion by dams, deep channels •Hydrological alterations by roads, barriers encircling wetlands •Pollution of all forms e.g. from industries, agriculture, communities, urbans, etc. •Over-extraction of groundwater •Minings(inland & off-shore), sand pumping, mineral, oil/gas extraction subsidence •Mega-projects, infrastructures development e.g. dams, roads, power plants, etc. •Population growth pressure on wetlands