Carbon sequestration by horticultural plants in East Calcutta Wetlands ecosystem, a Ramsar Site in India

Abstract

East Calcutta Wetlands (ECW) located at the eastern fringe of Kolkata metropolitan, India designated as a Ramsar Site (No. 1208). ECW receives municipal solid wastes and composite wastewater from the city and local artisans use this for horticulture, agriculture and pisciculture practices. Horticulture designated as ‘green industry’ sequester significant amount of carbon (C) in plant biomass and in soil, therefore, helps to mitigate greenhouse gases and combat against global climate change. Six horticultural plant species commonly cultivated in ECW ecosystems were selected for present study. C sequestration potential of horticultural plants depends on plant biomass and plant density in cultivation fields. Highest amount of C was sequestered (40.76±6.73 ton ha-1) by ixora, a perennial plant in plant biomass. In case of basil, also a perennial plant, significant portion of the living plant biomass was exported from ECW as economically important parts which constitute 5.79±0.96 ton ha-1 C. Highest amount of soil organic carbon (SOC) was recorded from marigold fields (50.36±24.88 ton ha-1) which also constitute highest amount of C (34.37±5.67 ton ha-1) in residual parts (RP). Horticulture practices can sequester more amount of C in the ecosystem either by residual parts or remaining living plant biomass than agricultural practices.