126
dry wt. (at Kakdwip) during monsoon in stem and 10.23 ± 1.24 ppm dry wt. (at
Bagmara) during premonsoon to 21.66 ± 2.05 ppm dry wt. (at Kakdwip) in leaf of
A. alba. In 2014, for the same species the values ranged from 16.74 ± 1.11 ppm dry
wt. (at Bagmara) during premonsoon to 39.97 ± 3.34 ppm dry wt. (at Kakdwip) during monsoon in root, 12.39 ± 1.64 ppm dry wt. (at Bagmara) during premonsoon to
30.95 ± 2.68 ppm dry wt. (at Kakdwip) during monsoon in stem and 9.26 ± 1.02 ppm
dry wt. (at Bagmara) during premonsoon to 21.69 ± 1.35 ppm dry wt. (at Kakdwip)
in leaf. During premonsoon in 2013, available Pb values in root, stem and leaf
ranged from 2.99 ± 0.05 ppm dry wt. (at Bagmara) during premonsoon to
15.98 ± 1.06 ppm dry wt. (at Sagar south) during monsoon in root, 1.91 ± 0.06 ppm
dry wt. (at Bagmara) during premonsoon to 13.98 ± 0.91 ppm dry wt. (at Lothian
Island) during monsoon in stem and 1.08 ± 0.11 ppm dry wt. (at Bagmara) during
premonsoon to 11.98 ± 1.03 ppm dry wt. (at Kakdwip) in leaf of A. alba. In 2014,
for the same species the values ranged from 4.57 ± 0.44 ppm dry wt. (at Bagmara)
during premonsoon to 19.46 ± 1.32 ppm dry wt. (at Kakdwip) during monsoon in
root, 3.35 ± 0.09 ppm dry wt. (at Bagmara) during premonsoon to 15.99 ± 1.30 ppm
dry wt. (at Kakdwip) during monsoon in stem and 2.97 ± 0.14 ppm dry wt. (at
Bagmara) during premonsoon to 9.08 ± 1.02 ppm dry wt. (at Kakdwip) in leaf
respectively. During premonsoon in 2013, available Hg values in root, stem and leaf
ranged from 0.02 ± 0.002 ppm dry wt. (at Bagmara) during premonsoon to
0.07 ± 0.001 ppm dry wt. (at Kakdwip) during monsoon in root, 0.02 ± 0.008 ppm
dry wt. (at Bagmara) during premonsoon to 0.06 ± 0.003 ppm dry wt. (at Lothian
Island) during monsoon in stem and 0.01 ± 0.006 ppm dry wt. (at Bagmara) during
premonsoon to 0.05 ± 0.001 ppm dry wt. (at Kakdwip) in leaf of A. alba. In 2014,
for the same species the values ranged from 0.03 ± 0.005 ppm dry wt. (at Bagmara)
during premonsoon to 0.08 ± 0.004 ppm dry wt. (at Kakdwip) during monsoon in
root, 0.02 ± 0.004 ppm dry wt. (at Bagmara) during premonsoon to 0.07 ± 0.001 ppm
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
2013 Premonsoon
2013 Postmonsoon
2013 Monsoon
2013 Premonsoon
2014 Postmonsoon
2014 Monsoon
Concentration of Hg (ppm dry wt.)
2.5
1.5
0.5
0
1
2
Fig. 5.16 Spatio-temporal variations of biologically available Hg for the years 2013 and 2014 in
the selected stations
5 Mangroves: A Sink of Heavy Metals
dry wt. (at Kakdwip) during monsoon in stem and 10.23 ± 1.24 ppm dry wt. (at
Bagmara) during premonsoon to 21.66 ± 2.05 ppm dry wt. (at Kakdwip) in leaf of
A. alba. In 2014, for the same species the values ranged from 16.74 ± 1.11 ppm dry
wt. (at Bagmara) during premonsoon to 39.97 ± 3.34 ppm dry wt. (at Kakdwip) during monsoon in root, 12.39 ± 1.64 ppm dry wt. (at Bagmara) during premonsoon to
30.95 ± 2.68 ppm dry wt. (at Kakdwip) during monsoon in stem and 9.26 ± 1.02 ppm
dry wt. (at Bagmara) during premonsoon to 21.69 ± 1.35 ppm dry wt. (at Kakdwip)
in leaf. During premonsoon in 2013, available Pb values in root, stem and leaf
ranged from 2.99 ± 0.05 ppm dry wt. (at Bagmara) during premonsoon to
15.98 ± 1.06 ppm dry wt. (at Sagar south) during monsoon in root, 1.91 ± 0.06 ppm
dry wt. (at Bagmara) during premonsoon to 13.98 ± 0.91 ppm dry wt. (at Lothian
Island) during monsoon in stem and 1.08 ± 0.11 ppm dry wt. (at Bagmara) during
premonsoon to 11.98 ± 1.03 ppm dry wt. (at Kakdwip) in leaf of A. alba. In 2014,
for the same species the values ranged from 4.57 ± 0.44 ppm dry wt. (at Bagmara)
during premonsoon to 19.46 ± 1.32 ppm dry wt. (at Kakdwip) during monsoon in
root, 3.35 ± 0.09 ppm dry wt. (at Bagmara) during premonsoon to 15.99 ± 1.30 ppm
dry wt. (at Kakdwip) during monsoon in stem and 2.97 ± 0.14 ppm dry wt. (at
Bagmara) during premonsoon to 9.08 ± 1.02 ppm dry wt. (at Kakdwip) in leaf
respectively. During premonsoon in 2013, available Hg values in root, stem and leaf
ranged from 0.02 ± 0.002 ppm dry wt. (at Bagmara) during premonsoon to
0.07 ± 0.001 ppm dry wt. (at Kakdwip) during monsoon in root, 0.02 ± 0.008 ppm
dry wt. (at Bagmara) during premonsoon to 0.06 ± 0.003 ppm dry wt. (at Lothian
Island) during monsoon in stem and 0.01 ± 0.006 ppm dry wt. (at Bagmara) during
premonsoon to 0.05 ± 0.001 ppm dry wt. (at Kakdwip) in leaf of A. alba. In 2014,
for the same species the values ranged from 0.03 ± 0.005 ppm dry wt. (at Bagmara)
during premonsoon to 0.08 ± 0.004 ppm dry wt. (at Kakdwip) during monsoon in
root, 0.02 ± 0.004 ppm dry wt. (at Bagmara) during premonsoon to 0.07 ± 0.001 ppm
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
2013 Premonsoon
2013 Postmonsoon
2013 Monsoon
2013 Premonsoon
2014 Postmonsoon
2014 Monsoon
Concentration of Hg (ppm dry wt.)
2.5
1.5
0.5
0
1
2
Fig. 5.16 Spatio-temporal variations of biologically available Hg for the years 2013 and 2014 in
the selected stations
5 Mangroves: A Sink of Heavy Metals