Blue Carbon Stock of the Bangladesh Sundarban Mangroves: What could Be the Scenario after a Century?

Abstract

The total blue carbon stock of the Bangladesh Sundarban mangroves was evaluated and the probable future status after a century was predicted based on the recent trend of changes in the last 30 years and implementing a hybrid model of Markov Chain and Cellular automata. At present 36.24 Tg C and 54.95 Tg C are stored in the above-ground and below-ground compartments respectively resulting in total blue carbon stock of 91.19 Tg C. According to the prediction 15.88 Tg C would be lost from this region by the year 2115. The low saline species composition classes dominated mainly by Heritiera spp. accounts for the major portion of the carbon sock at present (45.60 Tg C), while the highly saline regions stores only 14.90 Tg C. The prediction shows that after a hundred years almost 22.42 Tg C would be lost from the low saline regions accompanied by an increase of 8.20 Tg C in the high saline regions dominated mainly by Excoecaria sp. and Avicennia spp. The net carbon loss would be due to both mangrove area loss (~510 km 2 ) and change in species composition leading to 58.28 Tg of potential CO 2 emission within the year 2115.

Biomass and net primary productivity of mangrove communities along the Oligohaline zone of Sundarbans, Bangladesh

“…This value was higher than those reported for subtropical mixed mangrove forest at Ishigaki Island, southern Japan (78.6 Mg•ha −1 ; Suzuki and Tagawa 1983). The present value of accumulation of mean aboveground biomass was within the converted range of AGB from aboveground biomass carbon for Sundarbans mangrove forests (55.3-153.4 Mg•ha −1 C; Chanda et al 2016). Compared to the previous studies, the present study indicates that biomass productivity of the mangrove species in the present study was relatively high among the mangrove forests in the tropical and subtropical areas, showing that mean annual wood production of 7.1 Mg•ha −1 •yr −1 .…”

Is soil organic carbon underestimated in the largest mangrove forest ecosystems? Evidence from the Bangladesh Sundarbans

“…The Bangladesh Sundarbans is situated between 21º30' N and 22º30' N and 89º00' E and 89º55' E. The climate of the Sundarbans is warm, humid, and tropical, where annual precipitation varies from 1474 to 2265 mm and mean annual minimum and maximum temperature is between 29 o C to 31 o C (Chowdhury et al, 2016;Sarker et al, 2016). Based on the salinity variation, the Sundarbans naturally divides into three distinct zones based on the soil salinity; i) Oligohaline (LSZ) (<2 dS/m, ii) Mesohaline (2-4 dS/m) and iii) Polyhaline (>4 dS/m) (Siddiqi, 2001;Chanda et al, 2016b). Several studies have identified a relationship between tree species abundance along the east-west salinity gradient (Iftekhar and Saenger, 2008;Aziz and Paul, 2015;Sarker et al, 2016;Sarker et al, 2019a).…”

“…Sundarbans mangrove forest, Bangladesh. Legend colour represents three major salinity zones (Chanda et al, 2016b). ESRI Basemap Sources: Esri, HERE, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community.…”

State of research on carbon sequestration in Bangladesh: a comprehensive review

“…Detailed data on district-wise spatial distribution of existing carbon studies have been provided in Supplementary material 3. (Chanda et al, 2016). Even though species richness limits the use of species-specific allometric equations (Mizanur, Khan, Hoque, & Ahmed, 2015), the use of common equations of other countries will yield unreasonable estimates which posed doubt on the accuracy of national estimation (Ahiduzzaman and Islam, 2016;Mizanur et al, 2015).…”