Estimation of Carbon Storage and Sequestration by Tropical Urban Trees in Benin City, Edo State, Nigeria

Abstract

The present investigation was conducted to estimate carbon storage and sequestration by tropical urban trees in Benin City, Edo State, Nigeria. The non-destructive approach was adopted for the study with 65 trees out of 13 species randomly selected from Black Afara (Terminalia invorensis), Aridan (Tetrapleura tetraptera), Orange (Citrius sinensis), Ashoka (Polyathia longifolia), Teak (Tectona grandis), Oocarpa pine (Pinus oocarpa), Umbrella tree (Terminalia mantaly), Flame of the forest (Delonix regia), Opepe (Naucloa diderrichii), Dogoyaro (Azadirachta indica), Weeping fig (Ficus benjamina), Omo (Cordia melleni) and African Oil Bean (Pentacleethra macrophylla). Diameter at breast height, tree height and wood density were used as predicator variables to estimate total biomass, carbon storage and sequestration. The results revealed that estimations for total biomass were 797.23 kg while total carbon storage and total carbon dioxide sequestration were 398.67 kg and 1462.76 kg respectively. Out of the recorded 797.23 kg total biomass, above ground biomass was 632.76 kg while below ground biomass was 164.47 kg. The findings showed that Terminalia mantaly, Delonix regia and Cordia melleni had better carbon storage and sequestration capabilities. Our study recommended the cultivation of Terminalia mantaly, Delonix regia and Cordia melleni species in Benin City as a strategy for mitigating climate change effects and supporting environmental services. The findings of this investigation can offer significant data for urban forestry plans targeted at selecting suitable blend of tropical trees with superior carbon storage and sequestration performances.