Comparison Of Soil Carbon Stocks And Carbon Dioxide Effluxes In Different Forest Management Regimes In Eastern Mau Forest Reserve, Kenya

ABSTRACT

The attainment of green economy and low carbon climate resilient development in Kenya may be

hindered by competing human interest on forests and other natural resources. Eastern Mau forest

has experienced anthropogenic disturbance through encroachment and forest fires; that situation

prompted the deployment of heterogeneous forest management. This study aimed at comparing

the soil carbon stocks and soil CO2 effluxes in different forest management regimes on as well as

how soil temperature and soil moisture impacts on carbon stocks and soil CO2 effluxes in the study

area. The study was conducted between January and June 2016 in Sururu block of Eastern Mau

forest reserve, Kenya. A nested experimental design was used in data collection; where thirty two

sample plots were nested into four blocks (disturbed (fire) natural, undisturbed natural, plantation

and glades) established on the basis of forest management types. Ina 10m2 plot, data was collected

on soil carbon stocks, soil CO2 efflux and environmental controls (soil temperature and soil

moisture). The results indicated that estimated soil carbon stocks were as follows: undisturbed

natural (135.17± 35.99.0 Mg C-ha), disturbed natural forest by fire ( 134.52± 38.11 Mg C-ha) glades

(122.4 ±64.9 Mg C-ha), and plantation forest (116.51± 39.77 Mg C-ha ). However, there were no

significant differences in the mean carbon stocks between the four forest management regimes (F4,

16. =0.61, p=0.613). The mean soil CO2 efflux between the four forest management types was

significantly difference (F1 32. =3.01, p=0.033). The soil CO2 efflux levels recorded were as

follows; plantation forest (9.219 ± 3.067 g C M-2day-1), undisturbed natural forest (8.665 ± 4.818

g C M-2day-1), glades (8.592 ± 3.253 g C M-2day-1) and fire disturbed natural forest (7.198 ± 3.457

g C M-2day-1). Based on the results; forest disturbance impacts on soil stocks and therefore for

Kenya to achieves its Nationally Determined Contribution (NDC) targets of reducing Green House

Gases(GHG) emission by 30% relative to business as usual (BAU) emissions of 22 MtCO2e in

2030, natural forests and glades management regimes presented the best options. Therefore the

use of natural forest management regimes in the conservation of soil carbon stocks and in reducing

carbon dioxide efflux from the forests is recommended. Additionally a paradigm shift in forest

management to include management for non wood forest products and service such as carbon

stocks and climate stabilization is needed. Finally REDD+ process in Kenya should consider the

carbon stored by forests in its reference level establishment