Blue Carbon Financing of Mangrove Conservation in the Abidjan Convention Region: A Feasibility Study

Table 8: Blue carbon stocks in mangrove forests in West, Central and Southern Africa

Mean carbon storage (Mg/ha)

Total carbon storage (Tg)

Above- ground biomass

Top metre of soil

Below- ground biomass

Below- ground biomass

Above- ground biomass

Top metre of soil 354.4 317.1 324.2 321.4 321.6 321.6 340.8 368.3 343.4 320.2 317.5 316.3 322.2 333.5 322.0 ND 328.2 320.0 314.4

All stocks

All stocks

Mangrove area (ha)

Country

0.8 0.1 12.9

5.5 0.6 48.1

17.6 23.1 29.5 17.1 24.3 ND 24.4 20.9 20.2 22.3 29.3 23.7 28.6 ND 29.9 ND 22.0 26.9 ND

425.0 412.5 440.5 393.2 426.0 321.6 440.4 456.1 428.8 417.6 433.1 413.4 446.4 333.5 439.7 ND 414.2 428.1 314.4

0.3 0.0 4.4 0.0 0.1 ND 0.4 3.0 1.0 0.2 5.5 6.7 0.5 ND 25.6 ND 2.6 2.6 ND 53.1

6.5 0.7 65.3

53.0 72.3 86.9 54.7 80.1 ND 75.2 66.9 65.2 75.1 86.4 73.4 95.5 ND 87.8 ND 64.0 81.1 ND

Angola Benin Cameroon Congo Côte d’Ivoire D.R. Congo Eq. Guinea Gabon Gambia

15,400 1,800 148,300

0.1 0.3 ND 1.4 9.7 3.4 0.6

0.5 1.0 5.9 6.2

0.6 1.4 5.9 8.0

1,500 3,200

18,300 18,100 145,700 51,911 7,600

53.7 17.8 2.4 60.0 88.8

66.5 22.3 3.2 81.8 116.0 8.4 0.0 376.9 ND 49.7 40.9 0.1 854.1

Ghana Guinea Guinea-Bissau Liberia Mauritania Nigeria SãoTomé and Príncipe Senegal Sierra Leone

16.3 20.6 1.8 ND 75.3

188,900 280,600 18,900 40 857,300 ND 120,000 95,500 200 1,973,251

6.1 0.0 276.0 ND 39.4 30.6 0.1 642.4

ND 7.7 7.7 ND 158.6

Togo Total

Note: Above-ground biomass and below-ground biomass was calculated using biomass-to-carbon ratios of 1:0.46 and 1:0.39, respectively, after Howard, Hoyt et al. (2014), page 78 and 90, respectively. Total carbon storage was calculated by multiplying mangrove area by the mean carbon storage values in the table. Sources: Fatoyinbo and Simard (2013); Hutchison, Manica et al. (2014), Jardine and Siikamäki (2014).

Figure 7: Differences in reported mangrove area estimates, by source Sources: Corcoran, Ravilious et al. (2007); Spalding, Kainuma et al.( 2010); Giri, Ochieng et al. (2011); Fatoyinbo and Simard (2013); Hamilton and Casey (2016); Hutchison, Manica et al. (2014). Note: The figure illustrates the differences in the estimates presented in different sources, not changes in mangrove coverage over time.

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