出版社：The International Institute for Science, Technology and Education (IISTE)
摘要：Trees in agroforestry systems are potential sinks of atmospheric carbon (C) due to their fast growth, productivity, high and long-term biomass C stock. Soil under forest and agroforestry also plays a major role in global C sequestration. This study was initiated to assess woody species and soil C sequestration of traditional agroforestry practices. Three study sites (namely: Buriketu, Chire and Erba) were systematically selected based on the presence of traditional agroforestry practices. Forty eight sample quadrats (16 quadrats in each site) having an area of 20m x 20m (400 m 2 ) were used for vegetation biomass estimation. Soil organic carbon (SOC) was sampled by using “X” design at depths of 0-30cm within each quadrats. Woody species biomass carbon stocks were estimated using an allometry equation of Y (Kg) = 34.4703 - 8.0671 DBH + 0.6589 DBH 2 . The types of agroforestry practices found in the study area are scattered trees in farm lands (parkland agroforestry), homegarden and live fence system. The mean AGBC stock showed an increasing trend from DBH ≥ 5 cm to 71 cm while a decreasing trend was noticed greater than 71 cm diameter classes. The mean carbon stocks (Means±Std) of different carbon pools in the indigenous agroforestry practice were 47.82±10.09, 11.96±2.52, 59.77±12.61, 150.61±6.9, 210.39±14.1 for AGBC stock, BGBC stock, TBC stock, SOC and TCSD, respectively. CO 2 assimilation by total biomass of woody species ≥ 5cm DBH in traditional agroforestry practices was estimated to be 219.15ton/ha. Estimation of CO 2 sequestration indicated that indigenous agroforestry practices of the area have been sequestered (772.02 ton/ha). The results of the present study confirmed that indigenous agroforestry practice play a major role in climate change mitigation. This study was focused on the biomass carbon stock of woody species ≥5 cm DBH, however, woody species <5cm DBH, dead wood, dead standing trees, fallen branches and litter-fine woody debris were also have a potential for C stock, thus further study on these components is recommended to provide reliable information. Keywords Biomass carbon, Ecosystem services , Global warming, Soil organic carbon. DOI : 10.7176/JEES/9-5-03 Publication date :May 31 st 2019
关键词：Biomass carbon; Ecosystem services ; Global warming; Soil organic carbon.
