Climate and intertidal zonation drive variability in the carbon stocks of Sri Lankan mangrove forests

Abstract

is at the forefront of global mangrove conservation. It is the first country to officially protect all its remaining mangrove forests and has embarked on an ambitious plan to restore 10,000 ha of wetland during the United Nations Decade of Ecosystem Restoration. One incentive for this conservation effort is a recognition, based on research mostly done elsewhere, of the importance of mangroves for carbon sequestration and storage. However, a lack of data on Sri Lankan mangrove carbon pools, especially on soil organic carbon, has been recognized as a major impediment to national climate change mitigation strategies. The current work examined both above and below-ground carbon stocks of five important mangrove forests in Sri Lanka (Rekawa, Puttalam-Kalpitiya, Pambala-Chilaw, Batticaloa and Negombo) which are situated in the three major climate zones (dry, intermediate and wet) and therefore sample the main climatic drivers of spatial variability. Above-ground carbon, below-ground root carbon and soil carbon stocks of mangroves in Sri Lanka ranged from 75.5 to 189.1 Mg C ha − 1 , 7.9 to 14.3 Mg C ha − 1 and 643.6 to 1253.6 Mg C ha − 1 , respectively. The highest total mangrove carbon stock was recorded from the Rekawa lagoon which is in the intermediate climate zone (1455.4 Mg C ha − 1 ) while the lowest was found in the Batticaloa lagoon in the dry zone (734.7 Mg C ha − 1 ). Soil carbon stocks were substantially higher in the places where vegetation biomass and stand densities are high. Soil comprised 83-90% of the total mangrove carbon stocks at all sites, highlighting the large potential for release into the atmosphere as carbon dioxide if these habitats are disturbed. Overall, our study contributes important data that broadens our current understanding of how mangrove organic carbon pools vary spatially and with climatic zone.

Carbon stock at several types of mangrove ecosystems in Bregasmalang, Central Java, Indonesia

“…This research's average aboveground carbon stock is also within the range obtained in four Chinese provinces, from 12.0 to 150.2 Mg ha -1 (Meng et al 2021). Meanwhile, the below-ground carbon stock is within the range in Sri Lanka, according to Cooray et al (2021), i.e., 7.9-14.3 Mg ha -1 . The vegetation in conservation mangrove forests is also in the range obtained in Rufiji Delta (Tanzania), namely 28.18-299.43 Mg ha -1 and 16-164.51 Mg ha -1 (Monga et al 2022).…”

“…Mahmoudi et al (2022) also examined sediment carbon stocks in two other mangrove forests in the northern Persian Gulf, which showed higher yields than this research, at 867.4 Mg ha -1 and 728.4 Mg ha -1 , respectively. However, the value in this research is still within the range of soil carbon in Sri Lanka, according to Cooray et al (2021), which is 643.6-1253.6 Mg ha -1 . Furthermore, Cooray et al (2021) explained that soil carbon stocks are substantially higher in places where vegetation biomass and stand density are high.…”

“…However, the value in this research is still within the range of soil carbon in Sri Lanka, according to Cooray et al (2021), which is 643.6-1253.6 Mg ha -1 . Furthermore, Cooray et al (2021) explained that soil carbon stocks are substantially higher in places where vegetation biomass and stand density are high. Soil comprises 83-90% of the total mangrove carbon stock at all sites and has a high potential for release into the atmosphere as carbon dioxide when this habitat is disturbed.…”

Estimation of carbon stock at the mangrove forest of Sangkulirang District, East Kutai Regency, East Kalimantan Province

“…The complex mangrove root structures and waterlogged soils trap allochthonous organic material on top of deep carbon-rich peat composed primarily of dead root material [5]. Soil carbon can comprise up to 90% of mangrove organic carbon stocks [6]. the optimal function of carbon sequestration by mangroves reaches 77.9%, where the carbon absorbed is stored in mangrove biomass parts [4] and can absorb three times more carbon than other forest groups [5].…”

Morphological characteristics and biodiversity of mudskipper fish (Periophthalmus: Gobiidae) in mangrove ecosystem of coastal Bay of Tomini, Boalemo, Gorontalo Province, Indonesia

“…Tomini Bay is the largest bay in Indonesia and is located in the coral triangle initiative. One of the parts of the bay which has rich biodiversity is the mangrove ecosystem which plays an important role in improving coastal sea productivity, spawning area, and nutrient supply needed by various species of fish (Nguyen and Parnel 2017;Lapolo et al 2018), and potential of biodiversity (Cooray et al 2021). In addition, Sellang (2020) stated that the mangrove ecosystem is one of the most important and productive environments for fish species in tropical areas and subtropical estuaries, which can improve the fertility and productivity of the coastal area.…”