237
To sum up the entire discussion in this chapter, it is logical to state that population
density and biomass of mangroves are the two vital indicators on which the carbon
and nitrogen sequestration potential stands. On the basis of my observations on the
biomass of 1-year old mangrove seedlings, 11 year old trees (matured stage) and
population density of the seedlings/matured trees, the core findings are listed here in
points.
1. The salinity preference of mangroves is highly species – specific. Low saline
regions are preferred by Sonneratia apetala as reflected from high population
density (mean = 1.667 No.m
−2
± 0.594) and biomass of the species in the eastern
sector (mean value = 0.320 tonnes ha
−1
± 0.065) compared to the biomass of the
species in the western sector (mean value = 0.255 tonnes ha
−1
± 0.056) and the
central sector (mean value = 0.130 tonnes ha
−1
± 0.052).
2. Avicennia marina, Avicennia alba, Avicennia officinalis and Excoecaria agallocha have preference for high salinity. The order of mean biomass of A. marina is
highest in the central sector (0.422 tonnes ha
−1
± 0.095) followed by the western
sector (0.233 tonnes ha
−1
± 0.086) and the eastern sector (0.175 tonnes
ha
−1
± 0.062). The mean biomass of A. alba followed the order central sector
(0.545 tonnes ha
−1
± 0.136) > western sector (0.357 tonnes ha
−1
± 0.083) > eastern sector (0.245 tonnes ha
−1
± 0.099). Similar trend is observed in the mean
biomass of A. officinalis with highest value in the central sector (0.723 tonnes
ha
−1
± 0.165) followed by the western sector (0.456 tonnes ha
−1
± 0.060) and the
eastern sector (0.236 tonnes ha
−1
± 0.074). The mean biomass of E. agallocha is
0.219 tonnes ha
−1
± 0.075 in the central sector followed by 0.193 tonnes
ha
−1
± 0.070 in the western sector and 0.149 tonnes ha
−1
± 0.054 in the eastern
sector.
3. Considering the landscape of entire Indian Sundarban Biosphere Reserve area of
9630 sq. km and salinity as primary criteria, it is worthy to select Sonneratia
apetala for plantation in the western and eastern sectors of Indian Sundarbans,
whereas for central Indian Sundarbans the preferred species are Avicennia
marina, Avicennia alba and Avicennia officinalis.
4. Carbon and nitrogen sequestration is highly salinity-specific for mangrove species. A. marina, A. alba, and A. officinalis can store carbon and nitrogen efficiently in regions with high salinity (20–30 psu), whereas Sonneratia apetala
prefers low saline regions (2–10 psu) to store optimum carbon and nitrogen in
their vegetative parts.
In addition to true mangroves, the mangrove associate species are also noted for
their unique carbon storage potential. Porteresia coarctata [Roxb.] Tateoka, a perennial halophytic wild grass, relative of rice, member of Poaceae acts as a pioneer
species in the succession process of mangrove formation along the estuaries of India
(Jagtap 1985; Chaudhuri and Choudhury 1994; Mitra and Banerjee 2005). The species establishes on the newly deposited sediments and helps enhance sedimentation,
developing favourable substratum for the growth of other mangrove floral species.
A spatio-temporal study was done to evaluate the carbon storage potential of the
species in the east and west coasts of Indian sub – continent during 2001–2012.
Phase 3: Species – Wise Carbon and Nitrogen Sequestration Potential of Mangroves…
To sum up the entire discussion in this chapter, it is logical to state that population
density and biomass of mangroves are the two vital indicators on which the carbon
and nitrogen sequestration potential stands. On the basis of my observations on the
biomass of 1-year old mangrove seedlings, 11 year old trees (matured stage) and
population density of the seedlings/matured trees, the core findings are listed here in
points.
1. The salinity preference of mangroves is highly species – specific. Low saline
regions are preferred by Sonneratia apetala as reflected from high population
density (mean = 1.667 No.m
−2
± 0.594) and biomass of the species in the eastern
sector (mean value = 0.320 tonnes ha
−1
± 0.065) compared to the biomass of the
species in the western sector (mean value = 0.255 tonnes ha
−1
± 0.056) and the
central sector (mean value = 0.130 tonnes ha
−1
± 0.052).
2. Avicennia marina, Avicennia alba, Avicennia officinalis and Excoecaria agallocha have preference for high salinity. The order of mean biomass of A. marina is
highest in the central sector (0.422 tonnes ha
−1
± 0.095) followed by the western
sector (0.233 tonnes ha
−1
± 0.086) and the eastern sector (0.175 tonnes
ha
−1
± 0.062). The mean biomass of A. alba followed the order central sector
(0.545 tonnes ha
−1
± 0.136) > western sector (0.357 tonnes ha
−1
± 0.083) > eastern sector (0.245 tonnes ha
−1
± 0.099). Similar trend is observed in the mean
biomass of A. officinalis with highest value in the central sector (0.723 tonnes
ha
−1
± 0.165) followed by the western sector (0.456 tonnes ha
−1
± 0.060) and the
eastern sector (0.236 tonnes ha
−1
± 0.074). The mean biomass of E. agallocha is
0.219 tonnes ha
−1
± 0.075 in the central sector followed by 0.193 tonnes
ha
−1
± 0.070 in the western sector and 0.149 tonnes ha
−1
± 0.054 in the eastern
sector.
3. Considering the landscape of entire Indian Sundarban Biosphere Reserve area of
9630 sq. km and salinity as primary criteria, it is worthy to select Sonneratia
apetala for plantation in the western and eastern sectors of Indian Sundarbans,
whereas for central Indian Sundarbans the preferred species are Avicennia
marina, Avicennia alba and Avicennia officinalis.
4. Carbon and nitrogen sequestration is highly salinity-specific for mangrove species. A. marina, A. alba, and A. officinalis can store carbon and nitrogen efficiently in regions with high salinity (20–30 psu), whereas Sonneratia apetala
prefers low saline regions (2–10 psu) to store optimum carbon and nitrogen in
their vegetative parts.
In addition to true mangroves, the mangrove associate species are also noted for
their unique carbon storage potential. Porteresia coarctata [Roxb.] Tateoka, a perennial halophytic wild grass, relative of rice, member of Poaceae acts as a pioneer
species in the succession process of mangrove formation along the estuaries of India
(Jagtap 1985; Chaudhuri and Choudhury 1994; Mitra and Banerjee 2005). The species establishes on the newly deposited sediments and helps enhance sedimentation,
developing favourable substratum for the growth of other mangrove floral species.
A spatio-temporal study was done to evaluate the carbon storage potential of the
species in the east and west coasts of Indian sub – continent during 2001–2012.
Phase 3: Species – Wise Carbon and Nitrogen Sequestration Potential of Mangroves…