SWAMP FORESTS OF BANGLADESH.pptx

Swamp forest, Sylhet, Mangrove Forest, Ratargul forest, mangrove species, Swamp Forest definition, Types of Swamp Forest, Bangladesh wetlands vegetation. The Ratargul Swamp Forest, located in the Gowainghat area of Sylhet, is the only freshwater swamp forest in Bangladesh123. This unique ecosystem is naturally conserved under the Department of Forestry, Government of Bangladesh13.

The forest spans an area of 3,325.61 acres, including 504 acres declared as an animal sanctuary in 20151. It’s often referred to as the “Sundarbans of Sylhet” due to its rich biodiversity and unique landscape14.

The forest’s name comes from the word “Rata” or “Pati” tree, used by the locals of Sylhet14. The evergreen forest is situated by the river Goain and linked with the channel Chengir Khal14. Most of the trees growing here are the Dalbergia reniformis (করচ গাছ Koroch tree)1.

During the rainy season, the forest is submerged under 20–30 ft (6.1–9.1 m) water1. For the rest of the year, the water level is about 10 ft (3.0 m) deep1. The forest is flooded by water coming from the hills of India only in the monsoon period and makes a swamp2. Other times, it remains dry2.

The water level never remains at the same level in this forest. It depends on the number of rainfalls. The water level could be 15-20 feet in the forest on the time of heavy rainfall2. The main trees of this forest are zigzag-style Koroch and Hizal tree. The root of these trees is in two-level. One in the ground, and another in the mid-level which is used while the forest is flooded in the monsoon time2.

Among wildlife, monkeys, snakes, frogs, and many types of birds are seen here2. Four months in the monsoon period is considered as the best time to explore this forest2. You can hire a local wooden boat and spend a whole day wandering and relaxing in this beautiful green mystery2.

The Ratargul Swamp Forest is not just a place of natural beauty but also a testament to nature’s resilience and adaptability. It’s a living reminder that even in conditions that may seem inhospitable to us, life finds a way to thrive and flourish.

1. SWAMP FORESTS OF BANGLADESH -FLORISTIC COMPOSITION -STRATIFICATION -LIFE FORMS -ADAPTIVE AND CHARACTERISTIC SPECIES OF SWAMP FOREST OF BANGLADESH

2. WHAT IS SWAMP FOREST? Swamp forests are found on peat-poor soils that are permanently waterlogged. They may be created and maintained by land topography (basin swamps), hydrological barriers, and/or high water tables. Aquatic habitats in swamp forests may be sporadic, seasonal, or permanent.

3. TYPES OF SWAMP FOREST IN BANGLADESH Beach forests Fresh water swamp forest Mangrove forest or Tidal forest or saline water swamp forest

4. 1.BEACH FOREST Sea forests are found all over the sea beaches and river side. The soil is sandy having large amount of lime and salts but poor in nitrogen and other mineral nutrients. Saint Martin`s island is the perfect example of sea forest in Bangladesh. Dominant plants of beach forests are: Cocos nucifera Acanthus ilicifolius Pandansa foetida Borassus flabellifer Phoenix dactylifera

5. 2. FRESH WATER SWAMP FOREST Freshwater swamp forests, or flooded forests, are forests which are inundated with freshwater, either permanently or seasonally . They normally occur along the lower reaches of rivers and around freshwater lakes. Freshwater swamp forests are found in a range of climate zones, from boreal through temperate and subtropical to tropical . Plant species are- Cordia dichotoma Crataeva nurvala

6. 3 . MARINE WATER SWAMP FOREST Mangrove forests, also called mangrove swamps, mangrove thickets or mangals , are productive wetlands that occur in coastal intertidal zones . Mangrove forests grow mainly at tropical and subtropical latitudes because mangrove trees cannot withstand freezing temperatures . There are about 80 different species of mangrove trees. All of these trees grow in areas with low-oxygen soil, where slow-moving waters allow fine sediments to accumulate Main example of marine water swamp forest is S undarban in Bangladesh Plant species are- Nypa fruticans Heriteria fomes

7. FRESH WATER SWAMP FOREST Freshwater swamp forests, or flooded forests, are forests which are inundated with freshwater, either permanently or seasonally. Ratargul Swamp Forest is a freshwater swamp forest located in Gowain River, Fatehpur Union, Gowainghat , Sylhet , Bangladesh. Ratargul was once thought to be the only swamp forest in Bangladesh, and one of the few freshwater swamp forests in the world. Later, more swamp forests namely Jugirkandi Mayabon , Bujir Bon and Lokkhi Baor swamp forest were discovered in Bangladesh . The forest is naturally conserved under the Department of Forestry, Government of Bangladesh . Its area is 3, 325.61 acre including 504 acre declared as the animal sanctuary in 2015. It is known as the Sundarbans of Sylhet . This only swamp forest in Bangladesh is located 26 kilometres (16 mi) far from Sylhet . The forest's name comes from the word, "Rata" or " Pati " tree, used by the locals of Sylhet .

8. CLIMATE CONDITION OF RATARGUL SWAMP FOREST Tropical air from the northwest of Sylhet causes heavy rainfall. According to Sylhet Weather Centre, average annual rainfall is 4162 millimeters. July hosts the most rainfall, with measures averaging 1250 millimeters. December is the driest season with 74% relative density, compared to more than 90% in July and August. The forest is linked with the Gowain River through the lake Chengir Khal . During the rainy season, water from India overflows into the lake from the Gowain River and the forest becomes flooded. This continues through the wet season from May to early October. During this time of the year, the average high temperature hits 32° Celsius (~90° Fahrenheit), and In January, the coolest month, the average high sits around 12°C (~54°F). During the rainy season, the trees of the swamp submerge about 10 ft (somewhere even 15–20 ft ) under water but the forest emerges during the dry season.

9. PLANT DIVERSITY IN RATARGUL SWAMP FOREST 73 species of plants could be found in the forest till now. 80 percent of the forest area is covered with umbrella of the trees . Two layer of plants can be seen in the swamp forest. The upper layer consists of trees and the lower one consists of intense Schumannianthus dichotomus . The canopy of the plants spreads up to 15 meters of height . Though the forest is natural, the Forestry Department of Bangladesh has planted some watery plants like- Calamus tenuis , Neolamarckia cadamba , Barringtonia acutangula , Calamus tenuis . Banyan Tree is very common in the forest . Besides that, Barringtonia acutangula , Dalbergia reniformis , Crateva religiosa or Hygrophila (plant), Alstonia scholaris can also be seen .

10. MARINE WATER (SUNDARBAN) SWAMP FOREST Mangrove forests, also called mangrove swamps, mangrove thickets or mangals , are productive wetlands that occur in coastal intertidal zones Sundarbans is a mangrove area in the delta formed by the confluence of the Padma, Brahmaputra and Meghna Rivers in the Bay of Bengal. It spans the area from the Baleswar River in Bangladesh's division of Khulna to the Hooghly River in India's state of West Bengal. It comprises closed and open mangrove forests, land used for agricultural purpose, mudflats and barren land, and is intersected by multiple tidal streams and channels. Sundarbans is home to the world's largest area of mangrove forests . Four protected areas in the Sundarbans are enlisted as UNESCO World Heritage Sites, viz. Sundarbans West (Bangladesh), Sundarbans South (Bangladesh), Sundarbans East (Bangladesh) and Sundarbans National Park

11. CLIMATE OF SUNDARBAN SWAMP FOREST The climate in shundarbans is generally very pleasant and soothing. Ordinarily, the climate in sundarban ranges from 34 and 20 degree celcius and the rainfall is extreamly high. So, the waeather is almost moist and with the humid air from the Bay Of Bengal blowing constantly carrying 80% humidity. From October to March N orth E asterlies blow here. Where from March to September , the Westerly prevails.

12. PHYSIOGRAPHY OF SUNDARBAN SWAMP FOREST The Sundarbans mangrove forest covers an area of about 10,000 km2 (3,900 sq mi), of which forests in Bangladesh's Khulna Division extend over 6,017 km2 (2,323 sq mi) and in West Bengal, they extend over 4,260 km2 (1,640 sq mi) across the South 24 Parganas and North 24 Parganas districts . The mangrove-dominated Ganges Delta – the Sundarbans – is a complex ecosystem comprising one of the three largest single tracts of mangrove forests of the world. The larger part is situated in Bangladesh, a smaller portion of it lies in India. The Indian part of the forest is estimated to be about 40 percent, while the Bangladeshi part is 60 percent. The Sundarbans was originally measured (about 200 years ago) to be of about 16,700 square kilometres (6,400 sq mi). Now it has dwindled into about one-third of its original size. The total land area today is 4,143 square kilometres (1,600 sq mi), including exposed sandbars with a total area of 42 square kilometres (16 sq mi); the remaining water area of 1,874 square kilometres (724 sq mi )

13. LIFE FORMS OF SUNDARBAN SWAMP FOREST( ANIMAL) TYPE OF ANIMAL NUMBER OF SPECIES DOMINANT SPECIES Mamals 42 Panthera tigris , Axis axis , Sus scrofa Birds 315 Larus argentatus , Gallus gallus Snakes 18 Python molurus , Ophiophagus hannah Reptiles 35 Crocodile, ghorial , lizards Amphibians 8 Green toad, golden toad Fishes 219 Koral , loitta , rup chanda , churri

14. In general, the northern boundary and new depositions are characterized by Baen ( Avicennia marina , A. alba, A. officinalis ) flanked by foreshore grassland of Oryza coarctata ( Dhani grass). Baen is gradually replaced by Genwa ( Excoecaria agallocha ) and then Goran ( Ceriops spp .). The southern and eastern associates include Garjan ( Rhizophora spp .), Kankra ( Bruguiera spp .), and few patches of Sundari ( Heritiera fomes ). Hental ( Phoenix spp .) forest exists in relatively high land and compact soil. Dhundul ( Xylocarpus granatum ), Passur ( Xylocarpus mekongensis ) and Nipa fruticans ( Golpata ) palm swamps are extremely limited True Mangrove species = 26 Mangrove associates = 29 Family = 40 Genera = 60 Back mangrove species= 29 Total Species = 84 PLANTS OF SUNDARBAN SWAMP FOREST OR, FLORISTIC COMPOSTION OF SUNDARBAN

15. CLASSIFICATION OF SUNDARBAN SWAMP FOREST ( ON THE BASIS OF SALINITY) MILD SALINE AREA -Southern part of Sundarban -In rainy season silt are accumulated -content of salt is mild - humus are high Dominant species is: H eriteria fomes ( sundori ) Other species: E xcoecaria agollcha , X ylocarpus granatum , A moora cacullata , N ypa fruticans , X ylocarpus moluccensis

16. CLASSIFICATION OF SUNDARBAN SWAMP FOREST ( ON THE BASIS OF SALINITY) MID SALINE AREA -middle are of Sundarban -In rainy season silt are less accumulated -content of salt is mid - humus are lesser than mild Dominant species is: Excoecaria agollcha Other species: Pongamia globra , A vicennia alba, E rythrina indica , Acanthus ilicifolius

17. CLASSIFICATION OF SUNDARBAN SWAMP FOREST ( ON THE BASIS OF SALINITY) HIGH SALINE AREA -Moribund western delta of Sundarban -vegetation is low in this region -content of salt is very high all over the year - humus are absent there Dominant species is: Avicennia alba Other species: F lacourtia sepiaria , P remna integrifolia , P ongamia globra

18. PREPARED BY, MD. ABU DAUD ID: 18602121 DEPARTMENT OF BOTANY,CU

19. STUDENT LIST OF GROUP 4 SL NO NAME ID 01 MOHAMMAD MAHAMUDUR RAHAMAN 18602108 02 SHIAKAT UDDIN 18602109 03 SAHADAT HOSSAIN 18602111 04 NABILA CHOWDHURY SATO 18602112 05 UMMA SALMA NIZUM 18602113 06 MD. ABDUL ALIM 18602114 07 SUMAIYA AKTER 18602115 08 NUR ALAM 1860 2116 09 SABBIR KHAN 18602117

20. STUDENT LIST OF GROUP 4 END SL NO NAME ID 10 AFIA NAWAR TAHA 18602118 11 MASUM BILLHA 18602119 12 MD. SHOHAG HOSSEN 18602120 13 MD . ABU DAUD 18602121 14 RIMU DEVI 18602124 15 ABDULLAH FAISAL 18602125 16 SHANJIDHA ISLAM RIFAH 18602126 17 MST . UMMA SALMA SHANTY 18602127 18 SHARMIN AKTER 18602128