Results and discussion
The above ground carbon stock in Guyana varied widely in different regions and riverine ecosystem. Black mangrove in Region 1 recorded the maximum carbon stock (3841±195.17 Mg/ha) of all other regions and ecosystem, followed by red mangrove in Demerara river (841.09±87.69) (Figure 5). The carbon stock (Mg/ha) in region 1 was approximately 31 times higher than the lowest carbon stock (Mg/ha) observed in Region 4. This could be attributed to having higher diameter trees in Region 1. In fact, historically region 1 is poulated by local Amerindians who cares for nature and as such the region is still in pristine condition. Region 4 had the lowest carbon stock of all regions and ecosystem. This is highly poulated, and country’s capital city Georgetown is located here. People used to use mangrove bark for medicinal purposes and tannin production.
Black mangrove registered higher carbon content (Mg/ha) than red mangrove. Provided black mangrove carbon contribution were not taken into consideration, mean red mangrove would have exceled black mangrove (Figure 6).
The tree densisty (ha) of red mangrove was clustered around (1000-2000 trees / ha), meanwhile the same for black mangrove was a lot higher (Figure 7). Interestingly tree density in Region 3 was the highest, the carbon stock (Mg/ha) was much lower, however.
According to Alder and Kujik (2009), the high forest in Guyana has an above-ground stock of 181 Mg/ha. However this study revealed that mean carbon stock for black and red mangrove respectively was 3.5 times and 5.5 times higher that of high forest. This research confirmed validity of scieentifc claim that mangroves are one of the most productive, if not the most, ecosystems in the world. Guyana’s participation to REDD+ and climate change issues has been very momentous to the rest of the world as it is one of the few leading tropical countries that showing the low carbon economic trajectory while conserving forest resources. Although high forest has got proper attention for their ability to sequester carbon stock, mangroves did not. No MRV project so far been developed and in fact, no such scientific data is present in the literature. Acknowledging the huge potentials of mangroves, Guyana REDD+ implementing agencies should ponder upon enahncement of mangroves carbon stock through assisted regneration and plantation. Some plantation initiatives had been in place through Guyana Mangrove Restoration Project, however, this efforts were inadequate, and in fact, it paid very little attention to lobbey policy makers concerning inclusion of mangrove forest into the payment for ecosystem services (carbon services).
The total estimated above-ground carbon stock of the red and black mangroves in Guyana is 45±3 Terrgram (Figure 8). Stretching only about 0.14% of the total forest area, it contributes approximately 2% of the countries carbon stock. This figure did not include below ground carbon stock, soil carbon stock and other less dominant mangrove trees. In addition, currently we did not have estimate of area covered by riverine mangroves. As such, the total carbon stock of riverine ecosystem was not estimated. Therefore, it could safely be conclude that the actual carbon stock of the Guyana's mangrove had been higher than the findings of the study. Importantly, Guyana’s mangrove aboveground carbon stock is much higher than many countries e.g., 20 to 230 Mg ha-1 in the Pacific; 257 Mg ha-1 in Palau; 190 - 430 Mg ha-1 in Solomon Island and global average 147 Mg ha-1.
The total estimated above-ground carbon stock of the red and black mangroves in Guyana is 45±3 Terrgram (Figure 8). Stretching only about 0.14% of the total forest area, it contributes approximately 2% of the countries carbon stock. This figure did not include below ground carbon stock, soil carbon stock and other less dominant mangrove trees. In addition, currently we did not have estimate of area covered by riverine mangroves. As such, the total carbon stock of riverine ecosystem was not estimated. Therefore, it could safely be conclude that the actual carbon stock of the Guyana's mangrove had been higher than the findings of the study. Importantly, Guyana’s mangrove aboveground carbon stock is much higher than many countries e.g., 20 to 230 Mg ha-1 in the Pacific; 257 Mg ha-1 in Palau; 190 - 430 Mg ha-1 in Solomon Island and global average 147 Mg ha-1.