Soil organic carbon stock in natural and restored mangrove forests in Pichavaram south-east coast of India

Abstract

Mangrove ecosystem is one of the important coastal ecosystems providing ecological security of the coastal area and livelihood security to the coastal fishermen. Besides it plays an important role in carbon sequestration as large amount of carbon is stored in the below ground biomass. The role of mangrove restoration in carbon stocking has not been studied comprehensively either globally or nationally. The aim of the present study is to quantify the soil organic carbon stock and carbon sequestration rate of the different age groups of restored and natural stands of Pichavaram mangroves forest. The soil organic carbon stock of the upper soil layer (0–90 cm) of six different sites from natural mangrove stands, 21years, 17 years, 16 years, 15 years and 12 years old stands were 146.1(Mg C ha^-1), 99.29 (Mg C ha^-1), 93.18 (Mg C ha^-1), 57.41 (Mg C ha^-1), 95.54 (Mg C ha^-1) and 84.84 (Mg C ha^-1), respectively. Carbon sequestration rate of Pichavaram mangrove forests ranged from 2.33 to 4.44 g C m^-2 year^-1. The result of the study reveals that soil organic carbon stock and burial rate were high in natural mangrove area than the restored areas. In this regard, restoration and rehabilitation of mangroves is required for preserving the ecologically important mangroves ecosystem to mitigate the impacts of climate change.