129
during premonsoon to 36.98 ± 3.15 ppm dry wt. (at Kakdwip) during monsoon in
stem and 18.12  ±  1.34  ppm dry wt. (at Bagmara) during premonsoon to
30.68 ± 2.18 ppm dry wt. (at Kakdwip) in leaf. During premonsoon in 2013, available Pb values in root, stem and leaf ranged from 3.34  ±  0.06  ppm dry wt. (at
Bagmara) during premonsoon to 17.66  ±  1.23  ppm dry wt. (at Kakdwip) during
monsoon in root, 2.56  ±  0.31  ppm dry wt. (at Bagmara) during premonsoon to
14.98 ± 1.32 ppm dry wt. (at Kakdwip) during monsoon in stem and 1.08 ± 0.02 ppm
dry wt. (at Bagmara) during premonsoon to 9.09 ± 0.09 ppm dry wt. (at Kakdwip)
in leaf of A. marina. In 2014, for the same species the values ranged from
4.46 ± 0.31 ppm dry wt. (at Bagmara) during premonsoon to 18.57 ± 1.32 ppm dry
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Concentration of Pb (ppm dry wt.)
Root Premonsoon
18
16
14
12
10
8
6
4
2
0
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
Fig. 5.21 Spatio-temporal variations of Pb (in ppm dry wt) in vegetative parts of Avicennia alba
during 2013
Kakdwip
Harinbari
Chemaguri
Sagar south
Lothian island
Jambu island
Frasergunj
Gosaba
Chotomollakhali
Bali island
Sajnekhali
Bagmara
Concentration of Pb (ppm dry wt.)
Root Premonsoon
25
15
5
0
10
20
Stem Premonsoon
Leaf Premonsoon
Leaf Monsoon
Stem Postmonsoon
Leaf Postmonsoon
Stem Monsoon
Root Postmonsoon
Root Monsoon
Fig. 5.22 Spatio-temporal variations of Pb (in ppm dry wt) in the vegetative parts of Avicennia
alba during 2014
5 Mangroves: A Sink of Heavy Metals