130
wt. (at Kakdwip) during monsoon in root, 3.69 ± 0.88 ppm dry wt. (at Bagmara)
during premonsoon to 15.89 ± 1.03 ppm dry wt. (at Kakdwip) during monsoon in
stem and 2.71 ± 0.08 ppm dry wt. (at Bagmara) during premonsoon to
11.06 ± 0.69 ppm dry wt. (at Kakdwip) in leaf respectively. During premonsoon in
2013, available Hg values in root, stem and leaf ranged from 0.02 ± 0.009 ppm dry
wt. (at Bagmara) during premonsoon to 0.08 ± 0.005 ppm dry wt. (at Kakdwip) during monsoon in root, 0.02 ± 0.001 ppm dry wt. (at Bagmara) during premonsoon to
0.07 ± 0.004 ppm dry wt. (at Kakdwip) during monsoon in stem and 0.02 ± 0.009 ppm
dry wt. (at Bagmara) during premonsoon to 0.06 ± 0.002 ppm dry wt. (at Kakdwip)
in leaf of A. marina. In 2014, for the same species the values ranged from
0.03 ± 0.006 ppm dry wt. (at Bagmara) during premonsoon to 0.09 ± 0.002 ppm dry
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Concentration of Hg (ppm dry wt.)
Root Premonsoon
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
Fig. 5.24 Spatio-temporal variations of Hg (in ppm dry wt) in the vegetative parts of Avicennia
alba during 2014
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Root Premonsoon
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Fig. 5.23 Spatio-temporal variations of Hg (in ppm dry wt) in the vegetative parts of Avicennia
alba during 2013
5 Mangroves: A Sink of Heavy Metals
wt. (at Kakdwip) during monsoon in root, 3.69 ± 0.88 ppm dry wt. (at Bagmara)
during premonsoon to 15.89 ± 1.03 ppm dry wt. (at Kakdwip) during monsoon in
stem and 2.71 ± 0.08 ppm dry wt. (at Bagmara) during premonsoon to
11.06 ± 0.69 ppm dry wt. (at Kakdwip) in leaf respectively. During premonsoon in
2013, available Hg values in root, stem and leaf ranged from 0.02 ± 0.009 ppm dry
wt. (at Bagmara) during premonsoon to 0.08 ± 0.005 ppm dry wt. (at Kakdwip) during monsoon in root, 0.02 ± 0.001 ppm dry wt. (at Bagmara) during premonsoon to
0.07 ± 0.004 ppm dry wt. (at Kakdwip) during monsoon in stem and 0.02 ± 0.009 ppm
dry wt. (at Bagmara) during premonsoon to 0.06 ± 0.002 ppm dry wt. (at Kakdwip)
in leaf of A. marina. In 2014, for the same species the values ranged from
0.03 ± 0.006 ppm dry wt. (at Bagmara) during premonsoon to 0.09 ± 0.002 ppm dry
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Concentration of Hg (ppm dry wt.)
Root Premonsoon
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
Fig. 5.24 Spatio-temporal variations of Hg (in ppm dry wt) in the vegetative parts of Avicennia
alba during 2014
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Root Premonsoon
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Fig. 5.23 Spatio-temporal variations of Hg (in ppm dry wt) in the vegetative parts of Avicennia
alba during 2013
5 Mangroves: A Sink of Heavy Metals