seedlings recruitment: the case of sundarbans
TRANSCRIPT
International Review of Business Research Papers Vol. 16. No. 1. , March 2020 Issue, Pp. 55– 76
Seedlings Recruitment: The Case of Sundarbans
A.S.M. Helal Siddiqui1 and M. Masudur Rahman2
The Sundarbans is the single tract largest mangrove forest in the whole world. The forest occupies the south-west corner of Bangladesh. The forest cover an area of 6,017 km2, of which 4143 km2 are landmass and remaining 1874 km2 are under water bodies. The Sundarbans has a high biodiversity value in which is tidally inundated twice a day. Prain (1903) reported 334 species belonging to 245 genera of spermatophytes and pteridophytes. Chaffey et al. (1985) listed 66 species. Helalsiddiqui (1998) listed 130 species and 230 species (Helalsiddiqui , 2009) which are not all the mangroves. As regards plants, Bangladesh has 28 true mangrove species against occurrence of 70 species in the world. The seedlings recruitments in different periods of the major mangrove species vary significantly. The regeneration density after Chaffey et al., (1985) showed 38,390 per hectare. The result of regeneration study during the year 1996 to 2001 showed that yearly seedlings recruitment were 42,857, 29,129 and 25,324 per hectare per year in the less, moderately and strongly saline zones respectively. According to Siddiqi (1994), the seedlings recruitment was 27,750 per hectare per year. The another report by Hasnin the regeneration was 31,420 seedlings per hectare per year. Average seedlings recruitment in the year 2010 was found 33,133/ha/year. On the other hand the average total regeneration in the 2012 was 29,444 /ha/year of different major mangrove species. It was observed that the newly recruited regeneration in the different permanent sample plots (33 PSPs of Mangrove Silviculture Division of the Bangladesh Forest Research Institute) total regeneration was26,774(2015) to 35,566(2017) per /year/ha. of different major mangrove species from analyzed data in 2010 to 2019.The lowest regeneration recruitment of the different species was 27,750 per hectare per year. On the other hand the highest recruitment was 38,390 per hectare per year. In the Sundarbans the regeneration depends on the salinity zone and differs from location to location.
1. Introduction: The Sundarbans is the single tract largest mangrove forest in the whole world. The forest occupies the south-west corner of Bangladesh. The forest cover an area of 6,017 km2, of which 4143 km2 are landmass and remaining 1874 km2 are under water bodies. The Sundarbans has a high biodiversity value in which is tidally inundated twice a day. Prain (1903) reported 334 species belonging to 245 genera of spermatophytes and pteridophytes. Chaffey et al. (1985) listed 66 species. Helal Siddiqui (1998) listed 130 and 230 species (Helal Siddiqui, 2009) which are not all the mangroves. As regards _____________________________ 1Dr. A.S.M. Helal Siddiqui, Divisional Officer, Mangrove Silviculture Division, Mangrove Bhaban, Muzgunni, Khulna-9000.Bangladesh Forest Research Institute, Ministry of Environment, Forest & Climate Change, Chittagong, Bangladesh, Email: [email protected] 2Dr. M. Masudur Rahman, Director, Bangladesh Forest Research Institute, Ministry of Environment, Forest & Climate Change, Chittagong, Bangladesh, Email: [email protected]
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plants, Bangladesh has 28 true mangrove species against occurrence of 70 species in the world. Thus Bangladesh is represented by 40% of the world true mangrove species (Siddiqi, 2001). H. fomes, the dominant mangrove species is available only in the Indian Sundarban, Bangladesh and Myanmar. The species appears to be in stressed condition by over exploitation and environmental causes. In addition, Siddiqi (2001) stated that Bangladesh has lost 10% of the true mangrove species in recent years. A total of 334 species of plants were identified (Prain 1903, Heining 1892) belonging to 245 genera of Spermatophytes and Pteridophytes from the Sundarban forest and the adjoining areas. Whereas, Helal Siddiqui (2016) reported about 230 floral species in Sundarbans. There has been a change in the species composition of Sundarban mangrove flora (Khatun and Alam, 1987). But at present nearly about 66 Angiospermic and Pteriodophytic species are found in the Sundarban (Chaffey et al 1985). The Sundarban flora belongs to Indo-Malaysian Sub group (Rahman,M.M.2004) and characterized by the abundance of H. fomes, E. agallocha, Ceriops spp., Bruguiera spp., Sonneratiaapetala etc. Sundari (Heritierafomes) and gewa (Excoecariaagallocha) are the major tree species in the forest. The other important species are pasur (Xylocarpusmekongensis), goran (Ceriopsdecandra), keora (Sonneratiaapetala), amur (Amooracucullata), baen (Avicennia officinalis), kankra (Bruguiera sp.), shingra (Cynometraramiflora), khalshi (Aegicerascorniculatum), kirpa (Lumnitzeraracemosa), golpata (Nypafruticans), garjan (Rhizophora mucronata), dhundul (X. granatum). Due to overuse of the resources of the Sundarban, increase in salinity of soil and water, siltation of river lands, water pollution, inadequacy of regeneration in some areas etc., the floral and faunal species diversity has greatly been affected(Rahman, 2004).To know the real situation of the floral composition of Sundarbans this assignment has initiated the following case study. Floral composition of Sundarbans: Plenty of seedlings are recruited each year in the Sundarbans. The Mangrove Silviculture Division of the Bangladesh Forest Research Institute has been studying the regeneration status from 1980 by establishing Permanent Sample Plots (PSPs). There is a great variation in the appearance of seedlings of different species in three salinity zones of the Sundarbans. An article named Major ‘’Mangrove Species in the Permanent Sample Plots of the Sundarbans’’ by Dr. A.S.M. Helal Siddiqui, Divisional Officer, Mangrove Silviculture Division, Bangladesh Forest Research Institute and M. Masudur Rahman, Dtector, Bangladesh Forest Research Institute (BFRI)was published in 9th Global Business Research Conference 21-22 December, 2018 at Shangri-La Hotel, Kathmandu, Nepal and got following results as discussed here. Average seedlings recruitment in the year 2010 was found 33,133/ha/year. Among them, Heritierafomes constituted 43.16%, Excoecariaagallocha 31.89%, Ceriopsdecandra 10.76%, Bruguierasexangula3.52%, Avicenniaofficinalis 1.01%, Aegicerascorniculatum3.92%, Xylocarpusmekongensis 0.91%, Sonneratiaapetala 0.20%, Amooracuculata2.41%, Cynometraramiflora 1.21%, Nypafruticans 0.10%, Phoenixpaludosa 0.20%, Rhizophora mucronata 0.31%, Acanthus illicifolius 0.10% and Brownlowiatersa 0.30%. Sundari (H. fomes) shows better survival (9.4%) in less saline zone compared to the strong saline zone (4.05%) whereas gewa (E. agallocha) shows better survivability
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(17.84%) in the strongly saline zone compared to the less saline zone. Percentage of mangrove regeneration at different places in the Sundarbans varies year to year and location to location. It was observed that the newly recruited regeneration in the different PSP locations (Table 1) total regeneration per hectare was 29,444 of different major mangrove species, from analyzed data in 2012. Among them sundri constitutes 28%, gewa 21%, goran18%, kankra14%, and others 19%. Water salinity data differs location to location and season to season in the Sundarbans.
Table 1: Salinity Wise PSPs in the Sundarbans
Salinity Zone Sl no.
Location No. PSP’s
No. of Compt. Soil salinity (ppt)
Soil pH
Less Saline Zone
1 Nandabala 1 26 16.0 6.6
2 Jongra 3 30 17.0 6.4 3 Supoti(East) 4 3 6.0 5.2 4 Supoti(West) 5 5 6.0 6.4 5 Sarankhola 26 24 6.0 5.7 6 Mirgamari 25 28 13.0 6.2 7 Bagi 6 1 5.0 5.6 8 Dhangmari 13 31 17.0 6.5 9 Koramjol 14 31 18.0 6.6
10 Mora bhola 28 2 5.0 5.6 11 Supoti Khal 33 04 6.0 6.4
Moderate Saline Zone
12 Charaputia 2 15 19.0 5.2 13 Baniakhali 7 35 27.0 6.6 14 Kashiabad 8 36 25.0 6.6 15 Alkidives(East) 15 17 25.0 6.6 16 Alkidives(West) 16 17 25.0 6.2 17 Bosboja(East) 22 37 27.0 5.9 18 Bosboja(West) 23 37 27.0 6.0 19 Kalabogi 24 32 23.0 6.5 20 Katka 27 7 15.0 5.0 21 Bhadra 29 29 18 5.6 22 Charaputia 32 21 17.0 6.3
Strong Saline Zone
23 Gewakhali(W) 11 38 27.0 5.7 24 Sonamukhikhal 12 41 27.0 5.0 25 Ball River 17 41 26.0 6.0 26 Kadamtala 18 46 27.0 6.1 27 Chunkuri(East) 19 47 27.0 6.6 28 Chunkuri(West) 20 47 27.0 6.6 29 Kateshor 21 46 17.0 6.0 30 Koikhali 30 47 27.0 5.2 31 Burigoalini 9 46 28.0 6.2 32 Gewakhali(E) 10 20 19.0 5.0 33 Andermanik 31 41 26.0 6.6
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At the same, from a contemporary survey of 2018 in Permanent Sample Plots (PSPs) Mangrove Silviculture Division of the Bangladesh Forest Research Institute the following number of seedlings and salinity zone wise regeneration pattern (Figure-A, B&C) were observed in three salinity zones of Sundarbans.
19970
10939
15182
0
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Less Salinity Zone Moderate Salinity Zone Strong Salinity Zone
Num
ber o
f sap
lings
Figure A: Salinity zone wise sapling per/ha50
51
3818
3475
212
1374
91 71
343
222
121 33
3
141
111
0
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Num
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f sap
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Name of species
Figure B: Average % of saplings per/ha.
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Seedlings Recruitment in Different Zones of the Sundarbans A detailed survey was carried out on natural regeneration in 1983 by ODA. Three size classes (seedling, sapling and pole) were considered to count regeneration in the laid temporary sample plots (TSPs) (Table 2). The regeneration density was 38,390/ha of which seedling constituted approximately 75%, sampling 20% and pole 5% Chaffey et al.(1985)
1687
9
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242
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iera
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ecar
ia
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riops
de
cand
raXy
loca
rpus
m
ekon
gens
isBr
ugui
era
gym
norr
hiza
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erat
ia
apet
ala
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enni
a of
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alis
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iflor
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a ap
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ata
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a fr
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of s
eedl
ings
per
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Species
Figure C: Salinity zonewise regeneration pattern of mangrove species of the
Sundarban in October' 2018
Less Salinity Zone (> 5ppt)
Moderate Salinity Zone (5-18 ppt)
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Table 2: Regeneration (by Number per Hectare and Percent) of Seedlings, Saplings, and Poles for the Entire Sundarbans Covering Less, Moderate and
Strongly Saline Zones.
Species Regeneration Seedling
(Ht<1.3m) Sapling(Ht<1.3m, dbh<2.5 cm)
Pole (Ht>1.3m, dbh 2.5-4.9 cm)
Total
H.. fomes 11,960 (41.12%) 1,910 (25.30%) 450 (25.71%) 14,320 (37.30%)
E.. agallocha 13,080 (44.96%) 1,840 (24.37%) 610 (34.86%) 15,530 (40,45%)
Other species
4,050 (13.92%) 3,800 (50.33%) 690 (39.43%) 8,450 (22.25%)
Total 29,090 7,550 1,750 38,390 Source: Extracted from Chaffey et al.(1985) The seedlings recruitments in different periods of the major mangrove species vary significantly. The regeneration density after Chaffey et al., (1985) showed 38,390 per hectare. The result of regeneration study during the year 1996 to 2001 showed that yearly seedlings recruitment were 42,857, 29,129 and 25,324 per hectare per year in the less, moderately and strongly saline zones respectively. Hence the average number opined by Siddiqui (2001) 36,096 per/ha. According to Siddiqi (1994), the seedlings recruitment was 27,750 per hectare per year. On the basis of data collected from the temporary Sample Plots, Chaffey et al. recorded 29,090 seedlings/ha/year. The another report by Hasnin the regeneration was 31,420 seedlings per hectare per year. Average seedlings recruitment in the year 2010 was found 33,133/ha/year. On the other hand the average total regeneration in the 2012 was 29,444 /ha/year of different major mangrove species. The lowest regeneration recruitment of the different species was 27,750 per hectare per year. On the other hand the highest recruitment was 38,390 per hectare per year. The trees are a source of seed supply and may also help in the anchorage of seeds or propagules in the substratum. So, seedlings recruitment is expected to be dependent on tree density. But mangrove species in the Sundarban are non-viviparous with buoyant seeds, which after falling on the forest floor either washed away by tides fail to germinate elsewhere. Regeneration of the Sundarbans last ten years It was observed that the newly recruited regeneration in the different permanent sample plots (33 PSPs of Mangrove Silviculture Division of the Bangladesh Forest Research Institute) total regeneration was26,774(2015) to 35,566(2017) per /year/ha. Of different major mangrove species from analyzed data in 2010 to 2019. Actually the seedlings growing in the Sundarabns vary year to year depending on the availability of fruits and seeds. The survival number of newly recruited seedlings is very poor. The new seedlings are browsed by deer and in winter season the browsed seedlings become
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dead without inundation in the forest floor. It is given the seedlings recruitment in different zones of the Sundarbans last 10 years in table-3 & Fig-D.
Table 3: Seedlings Recruitment in Different Zones of the Sundarbans Year Name of
Species Salinity Zones Total
(Av. per/ha.) Less Moderate Strong
2010
Sundri 6667 6667 3333 5556 Gewa 4000 6333 15200 8511 Goran 2000 10000 16667 9556 Passur 333 433 1733 833 Kankra 400 8333 3500 4078 Keora 67 33 100 67 Baen 67 867 5933 2289 Amoor 833 1967 367 1056 Singra 233 233 67 178 Khalshi 100 233 500 278 Hantal 133 100 400 211 Hargoza 200 167 167 178 Hormoi 333 167 33 178 Batul 333 133 33 167 33133
2011
Sundri 13333 8333 6667 9444 Gewa 2633 13333 10000 8656 Goran 6667 5733 10000 7467 Passur 167 433 1733 778 Kankra 67 8333 2767 3722 Keora 67 33 100 67 Baen 67 867 5933 2289 Amoor 833 1967 367 1056 Singra 233 233 67 178 Khalshi 100 233 500 278 Hantal 133 100 400 211 Hargoza 200 167 167 178 Hormoi 333 167 33 178 Batul 333 133 33 167 34667
2012
Sundri 8833 5000 3333 5722 Gewa 3333 2867 6667 4289 Goran 200 767 25233 8733 Passur 400 1067 5433 2300 Kankra 33 11900 1067 4333 Baen 33 200 1300 511 Amoor 333 433 133 300 Singra 300 433 33 256 Khalshi 67 333 5967 2122 Jhana 167 333 267 256 Hantal 67 100 300 156 Golpata 500 333 167 333 Bhatkathi 67 167 167 133 14333 23933 50067 29444
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2013
Sundri 10000 6667 2167 6278 Gewa 10000 5000 1833 5611 Goran 33 1500 6233 2589 Passur 33 2833 5133 2667 Kankra 67 6367 3533 3322 Keora 67 0 0 22 Baen 67 4100 3333 2500 Amur 0 1667 67 578 Singra 200 233 167 200 Hantal 67 200 4000 1422 Khalshi 0 333 1567 633 Jhana 0 3333 1667 1667
20533 32233 29700 27489
2014
Sundri 13700 8567 8533 10267 Gewa 3000 11767 0 4922 Goran 33 533 18300 6289 Passur 267 33 300 200 Kankra 10667 4833 100 5200 Baen 100 267 0 122 Singra 500 33 0 178 Khalshi 0 67 3533 1200 Jhana 0 333 0 111 Amur 100 133 400 211 Hantal 200 0 0 67 28567 26567 31167 28767
2015
Sundri 822 933 822 859 Gewa 39244 5222 7544 17337 Goran 11 278 5944 2078 Passur 111 744 300 385 Kankra 1833 3667 111 1870 Baen 789 1033 711 844 Singra 211 0 0 70 Khalshi 11 0 9589 3200 Jhana 0 133 0 44 Amur 89 100 33 74 Hantal 22 11 0 11 43144 12122 25056 26774
2016
Sundri 21182 15606 12879 16556 Gewa 1576 1121 2879 1859 Goran 212 1818 5636 2556 Passur 1515 2424 1061 1667 Kankra 5879 4364 152 3465 Baen 455 1636 2576 1556 Singra 485 1667 0 717 Khalshi 0 0 545 182 Amur 152 30 303 162 Hantal 91 30 0 40 31545 28697 26030 28758
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2017
Sundri 6879 4758 485 4040 Gewa 8242 39636 3091 16990 Goran 61 636 14758 5152 Passur 667 909 2333 1303 Kankra 2788 8303 152 3747 Baen 455 636 30 374 Singra 758 30 0 263 Khalshi 0 30 9909 3313 Amur 394 394 182 323 Hantal 121 0 0 40 Golpata 0 61 0 20 20364 55394 30939 35566
2018 Sundri 16879 5091 636 7535 Gewa 788 3879 1061 1909 Goran 242 1152 30879 10758 Passur 364 121 2091 859 Kankra 7364 3182 667 3737 Keora 0 667 0 222 Baen 758 788 2212 1253 Singra 788 30 0 273 Khalshi 0 30 455 162 Jhana 0 364 91 152 Amoor 91 242 182 172 Hantal 0 0 576 192 Golpata 424 152 0 192 27697 15697 38848 27414
2019
Sundri 8515 3606 455 4192 Gewa 22212 37909 273 20131 Goran 364 515 9606 3495 Passur 242 424 242 303 Kankra 4394 3394 303 2697 Keora 0 91 0 30 Baen 909 121 970 667 Singra 1242 30 0 424 Khalshi 0 152 485 212 Jhana 0 30 0 10 Amoor 152 273 182 202 Hantal 61 0 0 20 Golpata 182 0 0 61 38273 46545 12515 32444
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The floristic composition of the Sundarbans is very rich in biodiversity compared to other mangrove forests of the world. The species composition of Sundarbans varies from location to location and salinity zones as well. An article that was published in 2016 named Flora and Faunal Resources and Ecosystem Conservation in the Sundarbans by Helal Siddiqui in International Journal of Agriculture Innovations and Research and result showed that 230 numbers of floral species was present in Sundarbans which all are not true mangroves. All of these species are given in Table-4.
3313
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2011
2012
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2017
2018
2019
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of s
eedl
ings
per
ha.
Year
Figure D: Regeneration Status from 33 PSPs in the Sundarbans
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
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Table 4: Vegetation of the Sundarbans and Adjacent Areas
Sl. No.
Scientific Name Family Vernacular Name Type of plant
1. Acacia nilotikaWilld. Leguminosae Babla Tree 2. Acalyphagodseffiana Linn. Euphorbiaceae Muktajhuri Small shurb 3. AcalyphaindicaLinn. Euphorbiaceae Muktajhuri Small herb 4. Acanthus ilicifoliusLinn. Acanthaceae Hargoza Scrambling, thorny herb 5. Achyranthesaspara Linn. Amaranthaceae Upang Rough chaff shrub 6. Acrostichumaureum Linn. Polypodiaceae Hodo,Tiger fern Gregarious fern 7. AegialitisrotundifoliaRoxb. Plumbaginaceae Dhalchaka Small tree 8. Aegicerascorniculatum Bl. Myrsinaceae Khalisha, khalshi Shrub or small tree 9. Aeschynomeneaspara Linn. Leguminosae Joloz Shola Grass 10. Aeschynomeneindica Linn. Leguminosae Joloz Shola Grass 11. AlbizialebbeckBenth. Leguminosae Kala koroy Tree 12. AlbiziaproceraBenth. Leguminosae Sadakoroy Tree 13. Albiziarichardiana King &Prain Leguminosae Raj koroy Tree 14. Amaranthus spinosus Linn. Amaranthaceae Kantanote Small spinusshurb 15. AmooracucullataRoxb. Meliaceae Amur Small tree 16. Aponogetonnatans Engl. Aponogetonaceae Swampy herb Swampy herb 17. Argemone maxicanaLinn. Papaveraceae Shialkanta Thorny weed 18. Argemone maxicana Linn. Papaveraceae Shialkata Thorny herb 19. Asparagus racemosusLinn. Lilliaceae Satamuli Climber 20. Avcennia officinalis Linn. Avicenniaceae Baen Tree 21. Avicennia alba Bl. Avicenniaceae Morchabaen Small tree 22. Avicennia marina Vierh. Avicenniaceae Sadabaen Small tree 23. BarringtoniaacutangulaGaertl. Barringtoniaceae Hijal Small tree 24. BarringtoniaracemosaSpreng. Barringtoniaceae Kumba, kumbi Small tree 25. BlumealaceraBurm. Compositae Bon gash Aromatic herb 26. Boerhaaviadiffusa Linn. Nyctaginaceae Punarnava Small herb 27. Borassusflabellifer Linn. Palmae Tal Palm tree 28. Boueahurmanica Griff. Anacardiaceae Muriam Small tree 29. BrownlowiatersaBenth. Tiliaceae Sundrilata Scandent shrub 30. BruguieragymnorrhizaLamk. Rhizophoraceae Kankra Tree 31. Bruguiera parviflora W. & A. Rhizophoraceae Kankra Tree 32. Bruguierasexangula Lam. Rhizophoraceae Kankra Medium tree 33. BuettneriaherbaceaRoxb. Sterculiaceae Kamraj Climber 34. BuettneriapilosaRoxb. Sterculiaceae Harjora Climber 35. Caesalpinia crista Linn. Leguminosae Kutumkatta Scandent, armed shrub 36. Caesalpiniasappan Linn. Caesalpinoidae Gulmo Scandent, armed shrub 37. Calamus tenuisRoxb. Palmae Bet Climber 38. Calophylluminophyllum Linn. Guttiferae Puinal Small tree 39. Calotropis proceraBr. Asclepiadaceae Akanda Shrub with coppices 40. Casiaalata Linn. Leguminosae Dadmordon Shrub 41. Casiafustula Linn. Leguminosae Sonalu Medium tree 42. Casiaoccidentalis Linn. Leguminosae Kalkasunda Shrub 43. Cassia sophera Linn. Leguminosae Kalkisinde Shrub 44. Casuarina littorea Linn. Casuarinaceae Jhau Tree 45. Cayratiapadata Linn. Vitaceae Gulialata Climber 46. Cayratia trifoliate Linn. Vitaceae Amal lata Climber 47. Celosia argentea Linn. Amaranthaceae Swampy weed Weed 48. Celosia cristata Linn. Amaranthaceae Swampy weed herb 49. Centalaasiatica Linn. Unbellifera Thakuni Small creeper 50. CerberamanghasGaertn. Apocynaceae Dagor Small tree
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51. CeriopsdecandraGriff. Rhizophoraceae Goran Small tree with coppices 52. CeriopstagalRobins. Rhizophoraceae Moth goran Small tree with coppices 53. Cissusquadrangularis Linn. Vitaceae Harvhangalata Climber 54. CissusRepens Lam. Vitaceae Marmarialata Climber 55. Clerodendrumviscosum Vent. Verbenaceae Ghetu Herb 56. ClerodendruminermeGaertn. Verbenaceae Sitka, sitki Scandent shrub 57. CocciniacordifoliaCogn. Cucurbitaceae Telakuchha Climber 58. Coixlachrymajobi Linn. Gramineae Kunce Weed 59. ColocasianymphaefoliaKunt. Araceae JongliKachu Herb 60. CrotolariasaltianaAndr. Papilionoideae Jhunjana Shrub 61. Croton bonplandianum Euphorbiaceae Putri Weed 62. Curcuma zedoria Rose. Zingiberceae Sothi Tuber like herb 63. CuscutareflexaRoxb. Convolvulaceae Swarnolata Parasite 64. Cymbopogon martiniRoxb. Graminae Gandhabena Herb 65. Cynodondactylon Linn. Graminae Durba grass Grass 66. Cynometraramiflora Linn. Leguminosae Shingra Shrub 67. CyperuscorymbosusRoxb. Cyperaceae Bon Mathi Grass like herb (sedge) 68. Cyperusdifformis Linn. Cyperaceae Behua Fodder grass 69. Cyperusiria Linn. Cyperaceae Motha grass Grass 70. DalbergiacandenatensisPrain. Leguminosae Chanda lota Scrambling climber 71. Dalbergia spinosaRoxb. Leguminosae Kalilota Scandent, armed shrub 72. Datura fastuosa Linn. Solanaceae Dhutra Shurb 73. Datura innoxia Mill. Solanaceae Dhutra Shurb 74. Delimasarmentosa Linn. Delliniaceae Salialata Climber 75. Dendrophthoe falcateEtt. Loranthaceae Porgassa Woody parasite in tree crown 76. Derris sinuataBenth. Leguminosae Mahajonilata Climber 77. Derris scandensBenth. Leguminosae Pan lota Climber 78. Derris trifoliata Lour. Leguminosae Gila lota Climber 79. Diospyros peregrine Gur. Ebenaceae Gub Tree 80. Doemia extensa Linn. Asclepiadaceae Dodhilata Climber 81. DrypetesroxburghiiHur. Euphorbiaceae Achet Scandent shrub 82. Echinochloacolonum Link. Graminae Grass Herb 83. Eclipta albaHassk. Compositae Keshraj Herb 84. EichorniacrassipesSolms. Lemnaceae Kachuripana Floating species 85. Eliocharis sp. JolGhash Basket making grass 86. Emilia sonchifolia DC. Compositae Sadhimodi Herb 87. Entada phaseoloidesMerr. Leguminosae Gila lata Climber 88. Equisetum arvenseRoxb. Equisitaceae Calamophyta Horse tail fern 89. Equisetum debile Roxb. Equisitaceae Calamophyta Horse tail fern 90. EriochloaproceraHubb. Gramineae Nol gash Grass 91. Erythrina variegate Linn. Leguminosae Bonmander Soft thorny tree 92. Eugenia fruticosaRoxb. Myrtaceae Ban jam Small tree 93. Eugenia lancaefoliaaRoxb. Myrtaceae Pania jam Medium tree 94. Eugenia operculataRoxb. Myrtaceae Tepa jam Medium tree 95. Eupatorium odoratumLinn. Compositae Asamlota Climber 96. Euphorbia antiquorum Linn. Euphorbiaceae Dudhia Herb 97. Euphorbia nivulia Ham. Euphorbiaceae sij Shurb 98. ExcoecariaagallochaLinn. Euphorbiaceae Gewa Tree 99. ExcoecariaindicaMuell. Euphorbiaceae Batla, batul Small tree 100. Ficusbengalensis Linn. Moraceae Bot Tree 101. Ficushispida L.F. Moraceae kakdumur Tree 102. Ficusmicrocarpa La. Moraceae Jir Tree with aerial roots 103. Ficusracemosa Linn. Moraceae Jogdumur Tree 104. Flagellariaindica Flagellariaceae Abetaa Climber
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105. Flueggeamycrocarpa Bl. Euphorbiaceae Sitka, sitki Scandent shrub 106. GirardianaheterophyllaDecene
. Urticaceae Gulmo Shurb
107. HedyotiscorymbosaLinn. Rubiaceae Khetpapra Grass 108. Heritierafomes Buch.-Ham. Sterculiaceae Sundri Tree 109. Hibiscus tiliaceous Linn. Malvaceae Bhola Shrub 110. HolarrhenaantidyssentericaWall
. Apocynaceae Kuriz Shrub
111. Hoya parasiticaWall. Asclepiadaceae Pargacha Epiphyte 112. Hydrilla sp. Joloz plant Fern 113. HydrocotylesibthorpiodesLam. Umbellifera Thankuni Herb 114. HygroryzaaristataNees. Gramineae Uridhan Grass 115. ImperataarundinaceaeLinn. Gramineae Songash Grass 116. Imperata cylindrical Beauv. Gramineae Dhanshi/ ulu Grass 117. IntsiabijugaKunt. Leguminosae Bhaela, bharal Small tree 118. IntsiaretusaKunt. Leguminosae Hinge Small tree 119. Ipomoea alba Linn. Convolvulaceae Dudhkalmi Succulent, herb 120. Ipomoea aquaticaForsk. Convolvulaceae Kalmisak Swamp creeper 121. Ipomoea fistulosa Mart.ex Convolvulaceae Dholkalmi Succulent, herb 122. Ipomoea hediraceaJack. Convolvulaceae Dudhkalmi Succulent, creeper 123. Ipomoea pescaprae Linn. Convolvulaceae Sagolkuri Succulent, herb 124. Ipomoea quamoclit Linn. Convolvulaceae Tarulata Cupid’s flower, creeper 125. Ixora arboreaRoxb. Rubiaceae Bon bakul Small tree 126. Jatrophacurcas Linn. Euphorbiaceae Bonveranda Shrub 127. Kaempferia rotunda Linn. Zingiberaceae Bhuichapa Tuber 128. KandeliacandelW. and A. Rhizophoraceae Gura, gurae, gural Small tree 129. Lagerastroemiaspeciosa Linn. Lythraceae Jarul Tree 130. LanneacoromandelicaMerr. Anacardiaceae Jiga Small 67eciduous tree 131. Lantana camara Linn. Verenaceae Chotra Lantana herb 132. Leeaaequata DC. Vitaaceae Kagjanga Shrub 133. LeersiahexandraSwartz. Leguminosae Arali Herb 134. LemnapaucicostataHegelm. Lemnaceae Khudipana Duck weed 135. LepisanthesrubiginosaLee. Sapindaceae Bon lichu Tree 136. LudwigiaadscendensHara. Onagraceae Keshordam Floting herb 137. LumnitzeraracemosaWilld. Combretaceae Kirpa, kripa Small tree 138. Lycopodium clavatum Lycopodiaceae Club moss Herb like fern 139. Macrosolencochinchinensis Loranthaceae Porgassa Woody parasite on crowns 140. Macuna gigantea Leguminosae Doyal Climber 141. MagniferaindicaLinn. Anacardiaceae Aam Tree 142. MallotusrepandusMuell.Arg. Euphorbiaceae Bon notoy Scandent shrub 143. Marsileapilularia Marsiliaceae Joloz fern Swampy soft plant 144. Marsileaquaadrifolia Marsiliaceae Joloz plant Swampy soft plant 145. Melochiacorchorifolia Linn. Sterculiaceae Tikiokra Herb 146. Mikania cordataRoxb. Compositae Asamlata Climbing hemp weed 147. Mikania scandensCI.. Compositae Tara lata Climbing hemp weed 148. MimusapudicaLinn. Leguminosae Lazzabati Shrub 149. Monochoria hastate Linn. Pontederiaceae Swampy weed Swampy grass 150. Mucunapruriens DC. Leguminosae Bilaiasra Climber 151. MyriostachyawightianaHook.f. Gramineae Dhanshi Grass, on new accretions 152. Nelumbo nuciferaGaertn. Nymphaeaceae Paddo Floating flower 153. Nymphaea nouchalliBurm. f. Nymphaeaceae Sadasapla Water lily 154. Nymphaea stellataWilld. Nymphaeaceae Shaluk Water vegetation 155. NypafruticansWurmb. Palmae Golpata Palm, underground stem 156. Ocimumamericanum Linn. Labiatae Bon tulshi Herb
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157. Ocimumbasilicum Linn. Labiatae Vuitulshi Shrubby basil 158. OperculinaterpethumSilva.Ma
nso. Convolvulaceae Dudhkalmi Climber, grass
159. Oryza coaractataRoxb. Gramineae Uridhan/ dhanshi Grass 160. Paederiafoetida Linn. Rubiaceae Ganda vadali Grass 161. Pandanus foetidusRoxb. Pandanaceae Kewakatta Prickly succulent pine 162. ParamignyacitrifoliaHk.f. Rubiaceae Bonlebu Shurb 163. PergulariadaemiaChiov. Asclepiadaceae Dudhialata Creeper 164. Petungaroxburghii DC. Rubiaceae Narikili Small tree 165. Phoenix paludosaRoxb. Palmae Hantal Thorny palm 166. Phoenix sylvestrisRoxb. Palmae Khejur Date palm 167. Phragmites karkaRtz. Gramineae Nolkagra Grass 168. Pistia stratiotes Linn. Araceae Topapana Water lettuce 169. Polygonum hydropiper Linn. Polygonaceae Panimoris Herb 170. Polygonum lanigerum Br. Polygonaceae Sadakukri Herb 171. Polygonum orientale Linn. Polygonaceae Bishkathali Herb 172. Polygonum plebejumBr.var. Polygonaceae Chemti sag Herb 173. Polypodium cuculatum Polypodiaceae Polypodium Fern 174. Polypodium parasiticum Polypodiaceae Polypodium Fern 175. Pongamiapinnata Pierre. Leguminosae Karanj, karanja Small tree 176. Potresia sp. Leguminosae Bunodhan Herb 177. Premnacorymbosa Linn. Verbenaceae Serpoli, setpoli Shrub or small tree 178. Psilotum nudum Psilotaceae Pteridophyte Rootless parasite 179. Pteris longifoliata Polipodiaceae Sun fern Sub aerial fern 180. RhinacanthuscommunisNees. Acanthaceae Juipana Floating pana 181. Rhizophora apiculata Bl. Rhizophoraceae Jhana Tree with stilt roots 182. Rhizophora mucronataLamk. Rhizophoraceae Garjan, Tree with stilt roots 183. Saccaharumbengalense Linn. Gramineae Jhati/Munda grass Grass 184. Saccaharum officinalis Linn. Gramineae Son Grass 185. SaccaharumspontaneumLinn. Gramineae Kash Grass 186. SagittariasagittifoliaLinn. Alismataceae Chotokut Tuber 187. Salacia chinensis Celastraceae Choytbarai Small tree 188. Salvi plebej Br. Labiatae BhuiTulshi Herb 189. SarcolobusglobosusWall. Asclepiadaceae Bowalilota Climber 190. Sargassum nereocystis Sargassaceae Brown shaibal Shaibal 191. Selaginellarupestris Selaginellaceae Club moss Prennial moss 192. SesbaniasesbanMerr. Liguminosae Katshola Common sesban 193. SidaacutaBurm. Malvaceae Kureta/Ban methi, Herb 194. Smilax zeylanica Linn. Liliaceae Kumari lata Creeper 195. Solanum indicumLinn. Solanaceae Bon begun Shurb 196. SonneratiaapetalaHam. Sonneratiaceae Keora Tree 197. SonneratiacaseolarisEngl. Sonneratiaceae Choyla Tree 198. Stenochlaenapaludosa Blechnaceae Dhekilata Climber 199. Stenochlaenapalustris Blechnaceae Dekilota Climbing fern 200. SyzygiumcuminiSkeels. Myrtaceae Jam Medium tree 201. SyzygiumoperculataRoxb. Myrtaceae Butijam Medium tree 202. TamarindusindicaLinn. Leguminosae Tentul Tree 203. Tamarix gallica Linn. Tamaricaceae Jhao, nonajhao Small tree 204. Terislongifoliata Polipodiaceae Common fern Sub aerial fern 205. Tetrastigmabracteslatum Vitidiaceae Golgotilota Climber 206. Thumbergia sp. Thumbergiaceae Jermanilota Climber 207. TinosporacordifoliaMiers. Menispermaceae Gulancha Creeper 208. Tragiainvoluerata Linn. Euphorbiaceae Bisuti Perennial hairy twinner 209. TrapabispinosaRoxb. Trapaceae Paniphal Floating plant
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210. TrewiapolycarpaBenth. Euphorbiaceae Pithali Small tree 211. Trichossanthescucumerina Cucurbitaceae Banchichinga Herbacious climber 212. Typha elephantianaRoxb. Typhaceae Hogla Grass used mat making 213. Typhoniumtrilobatum Schott. Araceae Ghetkachu Tuber 214. Urenalobota Linn. Malvaceae Banokra Small shurb 215. UtriculariaaureaLaur. Utriculariaceae Swampy weed Herb 216. Vallisueriaspirlis Linn. Hydrocharitaceae Bicha Climber 217. Vanda roxburghii Br. Orchidaceae Rashna Parasite 218. Vangueria spinosaRoxb. Rubiaceae Maina Small grass 219. Vetiveriazizanioides Hash. Gramineae Bena Grass 220. ViciahirsutaCoch. Leguminosae Bon lota Climber 221. Vigna radiata (L.)Wilizek. Leguminosae Arohilata Climber 222. Viscum album Linn. Loranthaceae Banda lota Woody parasite in tree crowns 223. Viscum orientaleWilld Loranthaceae Shamu lota Woody parasite in tree crowns 224. Vitex negundo Linn. Verbenaceae Nishanda Small shurb 225. Vitislanceolaria Laws. Vitaceae Harinialata Climber 226. Vitisquadrangularis Wall. Vitaceae Harjora Climber 227. Vitis trifoliate Linn. Vitaceae Anal lata Climber 228. Wolffia arrhiza Lemnaceae Shuzipana Floating duck weed 229. XylocarpusgranatumKoen. Meliaceae Dhundul Small tree 230. Xylocarpusmekongensis
Pierre. Meliaceae Passur Tree
However to formulate a study named ‘’Centralization and conservation of mangrove vegetation in three salinity zones of the Sundarbans’’ a midterm survey was conducted by Mangrove Silviculture Division of the Bangladesh Forest Research Institute and the following floral species was found from three salinity zones in Sundarbans (Table-5, 6 & 7).
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Name of Location: Munshiganj Name of compartment-46
Name of salinity zone-Strong saline water zone Table 5: Floral Species of Strong saline water zone in the Sundarbans.
Sl.No
Scientific Name Family Vernacular Name
Type of plant
1. Acanthus ilicifolius Acanthaceae Hargoza Scrambling, woody, thorny herb
2. Acrostichumaureum Pteridaceae Hodo,Tiger fern Gregarious fern 3. Aegicerascorniculatum Myrsinaceae Khalisha,
khalshi Shrub or small tree
4. Amooracucullata Meliaceae Amur Small tree 5. Avcenniaofficinalis Avicenniaceae Baen Tree 6. Brownlowiatersa Tiliaceae Sundrilata Scandent shrub 7. Bruguieragymnorrhiza Rhizophoraceae Kankra Tree 8. Ccriopsdecandra Rhizophoraceae Goran Shrub or small tree 9. Cuscutareflexa Convolvulaceae Swarnolata Parasite 10. Cynometraramiflora Leguminosae Shingra Shrub 11. Derris trifoliata Leguminosae Gila lota Climber 12. Excoecariaagallocha Euphorbiaceae Gewa Tree 13. Heritierafomes Sterculiaceae Sundri Tree 14. Hygroryzaaristata Gramineae Uridhan Grass 15. Imperatacylindrica Gramineae Dhanshi/ ulu Grass 16. Nypafruticans Palmae Golpata Palm 17. Phoenix paludosa Palmae Hantal Thorny palm 18. Sonneratiaapetala Sonneratiaceae Keora Tree 19. S. caseolaris Sonneratiaceae Choyla, ora Small tree 20. Typha elephantiana Typhaceae Hogla Grass used mat
making 21. Vanda roxburghii Orchidaceae Rashna Parasite 22. Xylocarpusmekongens
is Meliaceae Passur Tree
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Name of Location: Dhangmari Name of compartment-31
Name of salinity zone-Moderate saline water zone Table 6: Floral Species of Moderate Saline Water Zone in the Sundarbans.
Sl.No
Scientific Name Family Vernacular Name
Type of plant
1. Acanthus ilicifolius Acanthaceae Hargoza Scrambling, woody, thorny herb
2. Acrostichumaureum Pteridaceae Hodo,Tiger fern Gregarious fern 3. Aegicerascorniculatum Myrsinaceae Khalisha,
khalshi Shrub or small tree
4. Amooracucullata Meliaceae Amur Small tree 5. Avcennia officinalis Avicenniaceae Baen Tree 6. Brownlowiatersa Tiliaceae Sundrilata Scandent shrub 7. Bruguieragymnorrhiza Rhizophoraceae Kankra Tree 8. Caesalpinia crista Leguminosae Kutumkatta Scandent, armed
shrub 9. Ccriopsdecandra Rhizophoraceae Goran Shrub or small tree 10. Cuscutareflexa Convolvulaceae Swarnolata Parasite 11. Cynodondactylon Graminae Durba grass Grass 12. Cynometraramiflora Leguminosae Shingra Shrub 13. Dalbergia spinosa Leguminosae Kalilota Scandent, armed
shrub 14. Derris trifoliata Leguminosae Gila lota Climber 15. Eriochloaprocera Gramineae Nol gash Grass 16. Excoecariaagallocha Euphorbiaceae Gewa Tree 17. Heritierafomes Sterculiaceae Sundri Tree 18. Hibiscus tiliaceous Malvaceae Bhola Shrub 19. Hygroryzaaristata Gramineae Uridhan Grass 20. Imperatacylindrica Gramineae Dhanshi/ ulu Grass 21. Ipomoea aquatica Convolvulaceae Kalmisak Swamp creeper 22. Lumnitzeraracemosa Combretaceae Kirpa, kripa Small tree 23. Nypafruticans Palmae Golpata Palm 24. Phoenix paludosa Palmae Hantal Thorny palm 25. Rhizophora mucronata Rhizophoraceae Garjan, jhana Tree with stilt roots 26. Sonneratiaapetala Sonneratiaceae Keora Tree 27. S. caseolaris Sonneratiaceae Choyla, ora Small tree 28 Typha elephantiana Typhaceae Hogla Grass used mat
making 29 Vanda roxburghii Orchidaceae Rashna Parasite 30. Xylocarpusmekongens
is Meliaceae Passur Tree
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Name of Location: Sarankhola Name of compartment- 01
Name of salinity zone-Less salinity zone Table 7: Floral Species of Less salinity zone in the Sundarbans
Sl.No
Scientific Name Family Vernacular Name Type of plant
1. Acanthus ilicifolius Acanthaceae Hargoza Scrambling, woody, thorny herb
2. Acrostichumaureum Pteridaceae Hodo,Tiger fern Gregarious fern 3. Amooracucullata Meliaceae Amur Small tree 4. Avcennia officinalis Avicenniaceae Baen Tree 5. Brownlowiatersa Tiliaceae Sundrilata Scandent shrub 6. Bruguieragymnorrhiza Rhizophoraceae Kankra Tree 7. Buettneriapilosa Sterculiaceae Harjora Climber 8. Caesalpinia crista Leguminosae Kutumkatta Scandent, armed shrub 9. Cayratiapadata Vitaceae Gulialata Climber 10. Ccriopsdecandra Rhizophoraceae Goran Shrub or small tree 11. Cuscutareflexa Convolvulaceae Swarnolata Parasite 12. Cynodondactylon Graminae Durba grass Grass 13. Cynometraramiflora Leguminosae Shingra Shrub 14. Dalbergiacandenatensis Leguminosae Chanda lota Scrambling climber 15. Dalbergia spinosa Leguminosae Kalilota Scandent, armed shrub 16. Derris sinuata Leguminosae Mahajonilata Climber 17. Derris trifoliata Leguminosae Gila lota Climber 18. Eriochloaprocera Gramineae Nol gash Grass 19. Excoecariaagallocha Euphorbiaceae Gewa Tree 20 Excoecariaindica Euphorbiaceae Batla, batul Small tree 21. Flueggiavirosa Euphorbiaceae Sitka, sitki Scandent shrub 22. Heritierafomes Sterculiaceae Sundri Tree 23. Hibiscus tiliaceous Malvaceae Bhola Shrub 24. Hoya parasitica Asclepiadaceae Pargacha Epiphyte 25. Hygroryzaaristata Gramineae Uridhan Grass 26. Imperataarundinaceae Gramineae Songash Grass 27. Imperatacylindrica Gramineae Dhanshi/ ulu Grass 28. Ipomoea aquatica Convolvulaceae Kalmisak Swamp creeper 29. Kandeliacandel Rhizophoraceae Gura, gurae, gural Small tree 30. Lumnitzeraracemosa Combretaceae Kirpa, kripa Small tree 31. Nypafruticans Palmae Golpata Palm 32. Phoenix paludosa Palmae Hantal Thorny palm 33. Sonneratiaapetala Sonneratiaceae Keora Tree 34. S. caseolaris Sonneratiaceae Choyla, ora Small tree 35. Typha elephantiana Typhaceae Hogla Grass used mat making 36. Vanda roxburghii Orchidaceae Rashna Parasite 37. Vitisquadrangularis Vitaceae Harjora Climber 38. Vitis trifoliata Vitaceae Anal lata Climber 39. Xylocarpusmekongensis Meliaceae Passur Tree
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Threats and Problems of the Flora in Sundarbans The major mangrove tree species are facing different threats and Problems which being dead and decay last few decades. In the Sundarbans the major tree species are affected by different disorders as well as diseases. Forest diseases constituted one of the main biological determinants of forest productivity. They acquire increasing importance with changing emphasis from conservation to production in the forest. Disease and disaster may cause catastrophic damage to the forest. Various factors and pathogens causing disease to the major mangrove tree species(Helal Siddiqui,2009a). Considering the diseases and infestations of the economic important species in the Sundarbans it needs integrated research to overcome and to detect infestations of the problems in the Sundarbans. In the Sundarbans Sundri has been affected severely causing death of the trees from top down wards. It occurs throughout whole of the Sundarbans of Bangladesh more or less. At least 38% of Sundri trees are affected in the Sundarbans. Many probable causes have been mentioned for top dying problem but no real cause has been ascertained by the scientists. The disorders and diseases caused by different fungal pathogen. About 40% of the sundri population and more than 50% passur trees are affected by heart rot problem. The factors which causing these diseases is still not clearly identified but some biotic and abiotic factors are responsible for the causes. The wood loss becomes a very high rate which shall reflect the total loss of economy and the Sundarbans ecosystem. So, to overcome these disorders and diseases special monitoring, care, multi disciplinary research with field study, introduction of proper management system are to be required to formulate and eradicate these problems in the Sundarbans. General features and Disease condition Top Dying Problem of Sundri Sundri (Heritier fomes) is the most important tree species in the Sundarbans covering about 64% of the standing tree volume and constituting 52.7% of the area. Sundri, the most important tree species in the Sundarbans is not sound now. It is affected by top dying diseases. Top dying is generally regarded as a condition known as dieback or decline. The condition is characterized by a gradual loss of tree vigor which can lead to tree death. In another study the regeneration composition of the major species were measured and the vegetation with a view to evaluate the stand density within three salinity zones of the Sundarbans (Helal Siddiqui, 1999). Sundri (Heritierafomes) status and composition of trees and saplings in the fresh water zone of the Sundarbans were 48.58 % and 64.84% then followed by Gewa (Excoecariaagallocha) 30.41% and 34.80% respectively. Sundri (Heritierafomes) status and composition of trees and saplings in the Moderate Saline water zone of the Sundarbans was 20.23% and 29.18%. Gewa (Excoecariaagallocha) 12.97%, 37.85 Goran (Ceriopsdecandra) 9.02%, 0.08% and Passur (Xylocarpus mekongensis) 4.67%, 0.05% respectively. Sundri (Heritierafomes) status and composition of trees and saplings in the Saline water zone of the Sundarbans were 3.96% and 48.77%, Gewa (Excoecariaagallocha) 67.92% and 29.75% and Goran (Ceriopsdecandra) 16.53% and 2.25% respectively.
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Heart Rot Disease of Passur Passur is a valuable and highly useful tree species in the Sundarbans. It has a great commercial value. The natural vegetation of this species has been declined in a large scale in the Sundarbans due to disorder namely heart rot disease(Helal Siddiqui, 1998, 2009a, 2009b, 2010). The affected wood changes reddish to dark gray in colour and finally damages the timber. The causes of this disease have not been identified till to date. The infestation status of heart rot disease of pasur differ place to place and different locations of the Sundarbans. The analyzed result shows that it is heavily infested at Kalabogi then it is followed at Baniakhali. It was observed and enumerated heart rot infestation status of different locations in the SundarbansHelal Siddiqui and Khair (2012, Helal Siddiqui et al.2013). It is affected (Less than 50% top dead and more than 50% top dead or heart rot (Dhor observed) severely at Kalabogy, Baniakhali and Bozbosa are heavily affected in the moderately saline water zone. The result shows that the percentage is 64%, 62% and 60% respectively (Helal Siddiqui et al.,2013). Then followed by Kasiabad 54% and Chunkuri 48%.Very low number of trees are affected at Supati covering 17% in the fresh water zone of the Sundarbans. The results also show that in all the locations of the Sundarbans diameter at breast height (dbh.) Class III (31-40cm) is highly affected 51%, then followed by dbh Class II (21-30cm) 24% and Class IV (>40cm) 18% and the lowest only 7% in the Class I (<20cm). Water salinity data showed that the highest salinity found to occur at Chunkuri and lowest at Supati during May to November water salinity level decreases at all the locations and these raise up to 4 ppt at Supati. Die back of Gewa Gewa (Excoecariaagallocha) is second in importance. It constitutes about 16% 0f the forest. Root rot and die back of Gewa: About 15-20% of the (KNM) felled trees seems to be the cause of suffering die back of gewa, recently from root rot. Thus results in gradual death and lolling of affected trees. Mortality of Keora Keora( Sonneratiaappetala ), is one of the fast growing pionner tree species on the newly accreted land and along the river banks. Keora stands are heavily silted up covering the pneumatophores, Massive dieback and death of keora is seen to suffer near Kotka and Kochikhali (Helal Siddiqui, 2009a). Mortality of Baen Baen( Avicennia officinalis ), Die back and holling is another problem of baen. Most of old baen trees are affected by the problems. This is a great loss to the forest ecosystem and the country. The species is baen affected by mortality in the eastren zone of the Sundarbans (Helal Siddiqui,2002). Near the river banks the large trees are fying due to uneventual causes. The death may be caused by bark boring insects and wild lives and in turn destroying the jungle. To overcome this problen, it should be
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harvested properly before affected by top dying, old aged. So, management practices of those species must be changed. Conclusion The Sundarbans mangrove forest constitutes about 45% of total forest area and 4.2% of the total land area of the country (Islam 1993).To restore the Sundarbans ecosystem it needs increasing its productivity and conserve the resources and remaining unchanged of these species. Sundarbans biodiversity and its ecosystem are more essential commodities for the ecological point of view. The flora, fauna and the other factors of the Sundarbans are highly responsible for its ecotype protection and minimize natural calamities. Biodiversity of the Sundarbans is a great source of food, fodder, fuel wood, and medicine and shelter belt. Now the Sundarbans is deteriorating and degraded its biodiversity by different manmade and natural causes. Water salinity, water pollution, air pollution, green house effect as well as climate change and thus global warming are the causes of biodiversity loss and degradation of the Sundarbans. Illicit harvesting, poaching and weak management are responsible for degradation of the biodiversity. The continuous worldwide Biodiversity degradation is alarming. The dynamic nature of the ecosystem needs to be considered and an integrated management approach on a sustained yield basis needs to be initiated with the creation of true mangrove reserves to conserve the biodiversity at large. The status of the Sundarbans mangroves is still encouraging, considering tremendous biotic and abiotic interference on all the natural resources and consequent shrinkage of vegetation under other forest types. It is, therefore, imperative to carry out research for finding out more viable mangrove species which are susceptible to natural disasters, more suitable to the communities of Sundarbans as well as to combat adverse effect of climate change and to manage ecosystem on a sustainable basis in this delta for attaining sustainable development goals, vision-2021 and Delta plan in Bangladesh considering global perspectives. Increasing water salinity and decreasing up stream water flow of the Ganges (Farakka barrage) and other river the floral regenerations differ from zone to zone and location to location in the Sundarbans. The situation is not effective for the ecosystem of the Sundarbans. Sufficient fresh water flow with the upstream river is safe for the Sundarbans and its biodiversity. References Chaffey,D.R.; Millar, F.R. and Sandom, J.H. (1985). A Forest Inventory of the
Sundarbans, Bangladesh: Main Report. Project Report No. 140, Overseas Development Administration, London. 196 pp.
HelalSiddiqui, ASM (1999).Status of the Major Mangrove Species in the Sundarbans of Bangladesh.Indian Journal of Forestry. Voll.22. No.3: 197-202pp.
Helal Siddiqui, A.S.M. (2009a).The Disease and Disorder of the Mangrove Species in the Sundarbans. Abstract, Section II, Twenty First Bangladesh Science Conferene, BARI, Gazipur, 18-20 February,2009 23-24pp.
Helal Siddiqui, A.S.M. (2009b).Sundarbans and Visit to the Sundarbans.Published by AngikarProkashoni, 38 BanglaBazar, Dhaka. 287pp.
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Helal Siddiqui, A.S.M.(1998). EkPolock –A Sundarban(Sundarbans at a glance) Published by Rezina Begum .RiphatKuthir, Bhat ghara ,Kaliganj,Jhenaidah,ISBN-948-31-0272-2;64pp.
Helal Siddiqui, A.S.M.(2010).Heart Rot Scenarios of Passur (Xylocarpusmekongensis), an Important Mangrove Timber Species in the Sundarbans. In Badabon, Published by Sundarban Academy, Faraji para Lane, 29/1Sher E Bangla Road, Khulna-9100, 39-52 pp.
Helal Siddiqui, A.S.M., Dr. Abul Khair, DR. M. Masudur Rahman and S.M. MosfekaHasnin,(2013).Silvicultural aspect of passur (xylocarpusmekongensis) tree in the sundarbans with special reference to heart rot disease. Paper published; Pakistan Journal of Forestry, Pakistan Forest Institute, Peshawar 25120, Khyber Pakhtunkhwa, Pakistan, vol. 63(1).2013.
Helal Siddiqui, A.S.M.(2002). Silvicultural Aspect of Baen (Avecennia spp.)-The Pioneer tree species in the Sundarbans. Silver Jubilee Supplement of Indian Journal of Non-Timber Forest Products, Vol. 9(3/4):156-162 pp.
Helal Siddiqui, A.S.M.(2004). Plantation Establishment with Mangrove Tree Species in the Poorly Regenerated Areas of the Sundarban (Enrichment planting). Proceedings of the seminar, Organised by Mangrove Silviculture, Division, Bangladesh Forest Research Institute, Muzgunnni, Khulna-9000.123-129pp.
Helal Siddiqui, A.S.M.(2016). Flora andFaunal Resources and Ecosystem Conservation in the Sundarbans. International Journal of Agriculture Innovations and Research.Voluve 5, issue 3.
Helal Siddiqui, ASM and Khair. A.(2012).Infestation Status of Heart Rot Disease of Pasur (xylocarpus Mekongensis), Tree in the Sundarbans. Indian Forester, vol 138(2).
Khan, M.A.R.(1987).Wildlife in Bangladesh mangrove ecosystem. Journal of Bombay Natural History Society 83: 32-48.
Prain,D.(1903).Flora of the Sundarban. Records of the Botanical Survey of India. Periodical Expert Book Agency, Delhi.231-370 pp.
Rahman, M.M.(2004).Biodiversity Degradation in Mangrove Forest of Bangladesh. Proceedings of the seminar, Organised by Mangrove Silviculture Division, Bangladesh Forest Research Institute. Muzgunnni, Khulna-9000.21-37pp.
Siddiqi, N.A. (2001).Mangrove Forestry in Bangladesh. Institute of Forestry and Environmental Science, University of Chittagong, Chittagong.201 pp.
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