Assessment of Biomass and Carbon Stocks in Mangroves of Thalassery Estuarine Wetland of Kerala, South West Coast of India

Abstract

The mangrove ecosystems render many goods and services ranging from coastal protection to climate regulation. These ecosystems are also reservoirs of carbon stocks, due to their ability to sequester and store carbon in their biomass and the underlying sediment, and therefore significant in view of the climate change mitigation. The present study attempted to assess the biomass and carbon stock of mangroves of Thalassery estuarine wetland of Kerala, south-west coast of India. We assessed the carbon stocks of three carbon pools viz., above-ground, below-ground (root) and sediment. A total of eight species of mangroves were recorded from the Thalassery estuarine wetland, and of these, Avicennia officinalis was the dominant species with an average tree density of 729.37 individuals ha -1 and contributed most (45.05±23.79 t ha -1 ) to the total carbon. The overall mean above-ground biomass was 189.26±97.80 t ha -1 , while the overall mean root biomass was 83.06±40.48 t ha -1 . The estimated mean above-ground carbon was 94.63±48.90 t C ha -1 , while the mean carbon stock in root and sediment were 41.53±20.24 t C ha -1 and 17.48±7.30 t C ha -1 , respectively. In the present study, the estimates of mean combined C-stocks in mangrove and sediment showed that the mangroves of Thalassery estuarine wetland stored 153.64 t C ha -1 which was equivalent to 563.86 t CO2 ha -1 . The mangroves of Thalassery wetland cover an area of approximately 5.8 ha and thus it can be assumed that this wetland has the potential to sequester and store 891.11 t C, equivalent to an estimated amount of 3270.37 t CO2. The study reinforces the importance of mangrove forests as useful carbon sinks and the need for protection of these critical habitats in the light of climate change mitigation.

Biomass and vegetation carbon stock in mangrove forests of the Andaman Islands, India

“…This ratio is consistent with the global mean value, which is generally between 2.0 and 3.0 (Komiyama et al, 2008). The estimated T/R ratio in mangroves of Andaman Islands is comparable to that of Mahanadi Delta (T/R ratio of 2.3; Sahu et al, 2016), Kadalundi (T/R ratio of 2.38, Vinod et al, 2018) and Thalassery Wetland of Kerala (T/R ratio of 2.28; Vinod et al, 2019) and entire Kerala (T/R ratio of 2.17; Harishma et al, 2020); whereas the present study value is higher than that of Bangladesh (1.84; Kamruzzaman et al, 2017b), Thailand (1.05; Komiyama et al, 2000), New South Wales (1.3-2.0; Saintilan, 1997), and Japan (1.3;Kamruzzaman et al, 2017a). The T/R ratio of mangroves is often lower than trees of the terrestrial inland forest of tropical areas (5.1-10.7; Ogawa et al, 1965;Hozumi et al, 1969).…”

A contribution to understanding blue carbon sequestration and forest structure in mangroves of different ages in a small island (Mauritius)

“…The mean carbon storage for this study (642.56 t haˉ¹) falls within the global range of 55-1376 t haˉ¹ (Howard et al 2014b). The mean carbon stock obtained during this study was higher compared to the mean value obtained from a mangrove stand in Kerala, India consisting of eight different species (153.64 t haˉ¹: Vinod et al 2019) and in Farasan Islands in Saudi Arabia consisting of Rhizophora mucronata forest having 108 t haˉ¹ of organic carbon (Eid et al 2019). Comparing to other countries with different species, the mangrove Avicennia marina in Qatar had a total carbon stock of 45.70 t haˉ¹ which was very low compared to Mauritian mangrove forest (Chatting et al 2020) and a study in Berau and Segara Anakan Lagoon in Central Java, each site had a mean total organic carbon of 615 t haˉ¹ and 298 t haˉ¹ respectively (Kusumaningtyas et al 2018).…”

Evaluation of biomass and carbon storage potential of a natural mangrove stand in Muzhappilangad, Kerala, southwest coast of India

“…The tree density of Avicennia officinalis obtained in the present study was also higher when compared to the tree density of the same species in Mahanadi wetland reported by Sahu et al (2016). In Thalassery estuary which lies in close proximity to Muzhappilangad, A. officinalis was the predominant species with a tree density of 729.37 individuals ha -1 followed by A. marina which recorded a tree density of 471.43 individuals ha -1 (Vinod et al, 2019).…”