193
(3.90 ± 1.18) × 10
3
m
3
s
−1
, and the maximum of the order 4750 m
3
s
−1
during freshet
(September). Considerably lower discharge values were recorded during premonsoon
with an average of (1.19 ± 0.10) × 10
3
m
3
s
−1
, and the minimum of the order 861 m
3
s
−1
during May. During postmonsoon discharge, values were moderate with an average
of (2.03 ± 0.88) × 10
3
m
3
s
−1
almost similar to the data stated by earlier workers
(Mitra 2013; Mitra and Zaman 2015, 2016).
The central sector of Indian Sundarbans represents a hypersaline environment
due to complete obstruction of the fresh water flow from the upstream region owing
to Bidyadhari siltation since the late fifteenth century. Matla estuary in the central
Indian Sundarban cannot be referred to as an ideal estuary as there is no head on
discharge or dilution of the system with fresh water. Thus Matla can be designated
as a tidal channel, whose survival depends on the tidal flow from Bay of Bengal.
The eastern sector of Indian Sundarbans exhibits a low saline profile possibly
due to inter-connection with several creeks and channels of Harinbhanga estuary
(the aquatic border of India and Bangladesh Sundarbans) with the tributaries of
Bangladesh Sundarbans that originate from Padma – Meghna river system (Trivedi
et al. 2016).
In this chapter an attempt has been taken to develop a data bank on carbon and
nitrogen sequestration potential of dominant mangrove floral species distributed in 18
stations of the deltaic complex, 6 stations in each sector (W1–W6 in the western sector, C1–C6 in the central sector and E1–E6 in the eastern sector). For making the case
study easy to understand, the entire approach has been divided into 3 distinct phases.
Phase 1: Assessment of stored carbon and nitrogen in 1 year old seedlings of 5
dominant mangrove floral species (Assessment year was 2005).
Phase 2: Assessment of stored carbon and nitrogen in 11 years old trees of 5 similar
dominant mangrove floral species (Assessment year was 2015).
Phase 3: The difference between the results obtained in phases 1 and 2 has been
divided with the difference in years (here 10) to assess the carbon/nitrogen
sequestration (or carbon/nitrogen stored per year) of the selected species.
The methodologies adopted for these three phases along with the results and interpretations are discussed here separately.
Phase 1: Assessment of Stored Carbon and Nitrogen in 1 Year
Old Seedlings of 5 Dominant Mangrove Floral Species
Study Site Description
Deltaic complex of Indian Sundarbans has an area of 9630 sq. km and houses about
102 islands (Mitra 2000). 18 sampling sites were selected, 6 each in the western,
central and eastern sectors of Indian Sundarbans (Fig. 7.2). These three sectors of
Indian Sundarbans have been demarcated on the basis of secondary data on salinity
(Sengupta et al. 2013; Trivedi et al. 2016.).
Phase 1: Assessment of Stored Carbon and Nitrogen in 1 Year Old Seedlings of 5…
(3.90 ± 1.18) × 10
3
m
3
s
−1
, and the maximum of the order 4750 m
3
s
−1
during freshet
(September). Considerably lower discharge values were recorded during premonsoon
with an average of (1.19 ± 0.10) × 10
3
m
3
s
−1
, and the minimum of the order 861 m
3
s
−1
during May. During postmonsoon discharge, values were moderate with an average
of (2.03 ± 0.88) × 10
3
m
3
s
−1
almost similar to the data stated by earlier workers
(Mitra 2013; Mitra and Zaman 2015, 2016).
The central sector of Indian Sundarbans represents a hypersaline environment
due to complete obstruction of the fresh water flow from the upstream region owing
to Bidyadhari siltation since the late fifteenth century. Matla estuary in the central
Indian Sundarban cannot be referred to as an ideal estuary as there is no head on
discharge or dilution of the system with fresh water. Thus Matla can be designated
as a tidal channel, whose survival depends on the tidal flow from Bay of Bengal.
The eastern sector of Indian Sundarbans exhibits a low saline profile possibly
due to inter-connection with several creeks and channels of Harinbhanga estuary
(the aquatic border of India and Bangladesh Sundarbans) with the tributaries of
Bangladesh Sundarbans that originate from Padma – Meghna river system (Trivedi
et al. 2016).
In this chapter an attempt has been taken to develop a data bank on carbon and
nitrogen sequestration potential of dominant mangrove floral species distributed in 18
stations of the deltaic complex, 6 stations in each sector (W1–W6 in the western sector, C1–C6 in the central sector and E1–E6 in the eastern sector). For making the case
study easy to understand, the entire approach has been divided into 3 distinct phases.
Phase 1: Assessment of stored carbon and nitrogen in 1 year old seedlings of 5
dominant mangrove floral species (Assessment year was 2005).
Phase 2: Assessment of stored carbon and nitrogen in 11 years old trees of 5 similar
dominant mangrove floral species (Assessment year was 2015).
Phase 3: The difference between the results obtained in phases 1 and 2 has been
divided with the difference in years (here 10) to assess the carbon/nitrogen
sequestration (or carbon/nitrogen stored per year) of the selected species.
The methodologies adopted for these three phases along with the results and interpretations are discussed here separately.
Phase 1: Assessment of Stored Carbon and Nitrogen in 1 Year
Old Seedlings of 5 Dominant Mangrove Floral Species
Study Site Description
Deltaic complex of Indian Sundarbans has an area of 9630 sq. km and houses about
102 islands (Mitra 2000). 18 sampling sites were selected, 6 each in the western,
central and eastern sectors of Indian Sundarbans (Fig. 7.2). These three sectors of
Indian Sundarbans have been demarcated on the basis of secondary data on salinity
(Sengupta et al. 2013; Trivedi et al. 2016.).
Phase 1: Assessment of Stored Carbon and Nitrogen in 1 Year Old Seedlings of 5…