4. IN THE YEAR 2002 EAST KOLKATA WETLANDS HAS BEEN
RECOGNIZED AS WETLAND OF INTERNATIONAL SIGNIFICANCE
(RAMSAR SITE NO. 1208) TO UNDERSTAND THE CONCEPT OF
"WISE USE". IN THE PAST IT WAS RICH OF WILDERNESS AND WAS
WELL-KNOWN FOR ITS RICH FLORAL & FAUNAL DIVERSITY. TODAY
THIS VALUABLE NATURAL ASSET IS HIGHLY THREATENED DUE TO
THEPHENOMENON OFURBANIZATION.
5. • THE EAST CALCUTTA WETLANDS, ALSO KNOWN AS THE EAST KOLKATA
WETLANDS (22 0 27’ N 88 0 27’ E), ARE A COMPLEX OF NATURAL AND HUMAN-
MADE WETLANDS LYING EAST OF THE CITY OF KOLKATA, WEST BENGAL IN INDIA.
• THE WETLANDS COVER 125 SQUARE KILOMETERS, AND INCLUDE SALT MARSHES
AND SALT MEADOWS, AS WELL AS SEWAGE FARMS AND SETTLING PONDS.
• THE WETLANDS ARE USED TO TREAT KOLKATA'S SEWAGE, AND THE NUTRIENTS
CONTAINED IN THE WASTE WATER SUSTAIN FISH FARMS AND AGRICULTURE.
6. FLORA
• 30 GENERA OF PHYTOPLANKTON, 1) MYXOPHYCEAE, 2)
CHOLOPHYCEAE, 3) BACILLIARIOPHYCEAE, COINED
11,12,7 GENERAS.
• FROM DIFFERENT AREA 96 SPECIES OF VASCULAR
PLANT WERE FOUND WHICH MAINLY GROWS IN
WETLANDS & BANK REGION THIS SPECIES WERE UNDER
79 GENERA, 38 FAMILY.
• VASCULAR PLANTS COINED 62 SPECIES UNDER 53
GENERA & 25 FAMILIES OF DICOTYLEDON, 31 SPECIES
UNDER 23 GENERA & 10 FAMILY OF MONOCOTYLEDON &
ONLY 3 SPECIES UNDER PTERIDOPHYTES. ALL TOTAL
11. FAUNA
• THE PLANKTONIC DIVERSITY STUDY REVEALS 17 SPECIES OF
ZOOPLANKTONS, WHICH ARE COMMONLY FOUND.
• 3 CLADOCERAN SPECIES ARE COMMON TO FRESH WATER AND NOT
FOUND IN THE SEWAGE FED FISHERIES.
• 5 ROTIFER SPECIES ARE COMMON TO SEWAGE FED FISHERIES.
• 4 ORDER OF AQUATIC INSECT ARE BELONGING IN EKW VIZ.
HEMIPTERA, COLEPTERA, ODANATA AND DIPTERA.
• THIS AREA IS ALSO WELKNOWN FOR MIGRATORY BIRDS.
18. BIOREMIDIATION:-
PURIFICATION OF BHERI:
• BY A SEAWING CHANNEL WATER COMES TO THE BHERI. WHERE THE
SUSPENDED AND CORE SUSPENDED METERIAL IS REDUCED. THE DEPTH OD
THE BHERI IS 50-150 CM.
• NOW WATER TREATED WITH ALKALI AND LIME WHICH MAIMTAIN ALKALINE PH
WHICH MUST TO REDUCE COLIFORM COUNT.
• NOW THE WATER RICH IN ORGANIC CONTENT WILL BE
MANUALLY EROTED & O2 CONCENTRATION GET HIGHER.
• NOW SUNLIGHT RICH TILL BOTTOM THROUGH AND THROUGH
EROTION AND PLANKTON GROWS.
19. SEWAGE WATER TREATMENT:
• PLANKTONS ARE ALLOWED TO GROW FOR INDEFINIT TIME, BEFORE REACHING THE
PLANKTON BLOOM THE FISHES RELEASE WHICH FED UPON THE PRIMARY
PLANKTON.
• AGAIN THE NO. OF PHYTOPLANKTONS ARE GROWING AND FISH RELEASE WHICH
FED ZOOPLANKTON AS WELL AS PHYTOPLANKTON.
• THE ENTIRE ORGANIC MATTER WHICH CAME WITH RAW SEWAGE WAS CONSUMED
BY PLANKTON AND PLANKTONS ARE FURTHER CONSUMED BY FISHES.
• IN COMPARE TO RAW SEWAGE WITH BHERI AFETR TREATMENT 90-96% COLIFORM
COUNT ARE DECREASES.
• THERE IS LARGE DECREASE IN METAL
CONTENT.
20. • DURING BIOREMEDIATION FISHES ARE GROWN. WHICH IS ONE THIRED,
SOURSE OF FISH REQUIRED IN THE MARKETS OF KOLKATA.
21. • AFTER TERATED THE RAW SEWAGE, WATER OF BHARI USED FOR IRRIGATION
PURPOSE TO THE ADJOINING AREAS OF THE BHARI.
• EACH BHARI HAS ITS SURROUNDING FIELS.
• IT IS NOT WATER WHICH IS USED, AFTER EVERY ROUND OF CULTIVATION
BHARI IS NEED TO DRY. THE SILT IS DEPOSITED AT THE BOTTOM WHICH IS
ABSOLUTELY FERTILE SPREAD ON THE SURROUNDING FIELDS.
• AND DEPTH OF THE BHARI IS MAINTAINED.
• A MEJOR PORTION OF VEGETABLE PRODUCE
WHICH IS REQUIRED BY ENTIRE CITY.
23. • THIS WETLAND WORK AS A FREE SEWAGE TREATMENT PLANT OF KOLKATA
CITY, A FERTILE AQUATIC GARDEN AND, MOST IMPORTANTLY A FLOOD
DEFENCE – BUT IT IS UNDER THREAT FROM DEVELOPERS. 91.53 HECTARE
AREA URBANIZED.
24. • TTHEFT IS A MAJOR PROBLEM OF FISHERY. THE FISHES PRODUCE IN THE
FISHERY IT WAS STOLEN. SO THE OWNERS OF FISHERY FACED A HUGE
DAMAGE.
25. • DHAPA IS A DUMPING SITE NEAREST TO THE EKW. JUST BESIDE THE
IRRIGATION FIELD A GARBAGE MOUNTAIN IS STANDING.
26.
27. • IT IS ONE OF THE BEST INTEGRATED RESOURCE
RECOVERY IN THE WORLD.
• NOT ONLY SEWAGE TREATMENT, FISHERY, IRRIGATION,
IT GENERATE LOTS OF HUMAN RESOURCE IN TERMS OF
EMPLOYMENT ALONG WITH ENVIRONMENTAL DAMAGE
PREVENTION.
• THIS IS THE BOON OF CITY KOLKATA AND IT IS
ABSOLUTELY NEED TO BE PRESURVED. WITHOUT
WHICH THE DETOXIFICATION OR BIOREMEDIATION