Assesment of Carbon Sequestration and Biomass Accumulation of Managed and Natural Mangrove Plantations of Mida Creek, Kilifi County Kenya
No Thumbnail Available
Date
2021
Authors
Omollo, Kevin, Ogolla
Journal Title
Journal ISSN
Volume Title
Publisher
Kenyatta University
Abstract
Mangrove forests play a significant role along the coastal environment throughout the tropical coast. They provide ecosystem services that are able to sustain both flora and faunal organisms found in such ecosystems. They are stores of large quantities of carbon in their biomass hence referred to as carbon sinks. This carbon can be emitted into the atmosphere when mangrove forests are degraded through unsustainable utilization. With accurate quantification of carbon stocks in these forests, it will be easy to define their potential role in global climate regulation through their carbon sequestration ability. Since the sequestration potential of the replanted managed mangrove species of Mida Creek is unknown, this indicates an information gap which calls for bridging to help develop a baseline inventory data for effective forest conservation and management. The main objective of this study is to quantify the amount of carbon sequestered by the managed mangrove forest of the Mida Creek, Kenya. Three sites were selected for this study; 15 year-old Kibusa Plantation, 20 year-old Green Island Plantation, and a Natural Stand. Fifty Plots in the plantations and sixty plots in the natural stand of (10 x10) m2 were selected in each study site. Three carbon pools were investigated; aboveground carbon, belowground carbon, and soil organic carbon. Biomass for carbon determination in Kibusa and Natural Stands was estimated using a general allometric equation. Aboveground carbon was determined by measuring the diameter at breast height using a DBH meter. Belowground biomass and soil organic carbon was determined through root coring method using a soil corer at different depth profiles. Mean total carbon stocks in Kibusa and Green Island Plantations was 424.52±11.68 Mg C/ha and 958.57±50.01 Mg C/ha while the natural stand contained significantly higher total Carbon stocks of 2159.77±31.09Mg C/ha. There was no significant difference in the amount of soil organic carbon among the three different sites (F0.05(1)2,15=0.35, p>0.05). This study indicates that reforestation enhances structural development of replanted mangroves and that replanted mangroves are significant carbon stores. Rhizophora mucronata species was found to be the most abundant species compared to all the other species in all the three study sites, with an Importance Value Index of 117.1. In addition, Ammonium, Phosphates and Nitrates from the soil were also determined. Ammonium was the most abundant nutrient in all the three study sites. High Ammonium concentration in the mangrove sediment led to high amount of carbon sequestered in the root biomass. Therefore high ammonium concentration in the soil leads to increase in amount of carbon sequestered in the root biomass. From these results, we can deduce that awareness should be raised among the community members on the need for conservation and reforestation that will increase the amount of carbon sequestered since more mangroves increase the amount of carbon (IV) oxide capture. This will help in mitigating the issue of global warming at local levels.
Description
A Thesis Submitted in Partial Fulfillment of the Requirements for the Award of the Degree of Masters of Sciences (Plant Ecology) in the School of Pure and Applied Sciences of Kenyatta University
Keywords
Carbon Sequestration, Biomass Accumulation, Mida Creek, Kenya, Kilifi County