Abstract
BackgroundThis study investigated the variation of soil organic carbon in four land cover types: natural and mixed forest, cultivated land, Eucalyptus plantation and open bush land. The study was conducted in the Birr watershed of the upper Blue Nile (‘Abbay’) river basin.MethodsThe data was subjected to a two-way of ANOVA analysis using the general linear model (GLM) procedures of SAS. Pairwise comparison method was also used to assess the mean difference of the land uses and depth levels depending on soil properties. Total of 148 soil samples were collected from two depth layers: 0–10 and 10–20 cm.ResultsThe results showed that overall mean soil organic carbon stock was higher under natural and mixed forest land use compared with other land use types and at all depths (29.62 ± 1.95 Mg C ha− 1), which was 36.14, 28.36, and 27.63% more than in cultivated land, open bush land, and Eucalyptus plantation, respectively. This could be due to greater inputs of vegetation and reduced decomposition of organic matter. On the other hand, the lowest soil organic carbon stock under cultivated land could be due to reduced inputs of organic matter and frequent tillage which encouraged oxidation of organic matter. ConclusionsHence, carbon concentrations and stocks under natural and mixed forest and Eucalyptus plantation were higher than other land use types suggesting that two management strategies for improving soil conditions in the watershed: to maintain and preserve the forest in order to maintain carbon storage in the future and to recover abandoned crop land and degraded lands by establishing tree plantations to avoid overharvesting in natural forests.
Highlights
This study investigated the variation of soil organic carbon in four land cover types: natural and mixed forest, cultivated land, Eucalyptus plantation and open bush land
Soil organic carbon inventories are characterized by large uncertainties that may result from: (i) the large spatial variability of soil properties and resulting SOC stock (Don et al 2011, 2007), (ii) the imperfect knowledge of the link between environmental conditions and SOC stocks, and (iii) the limitation of regional data sets to represent the small variability of soil properties (Homann et al 1995)
Factors that may be important for increasing SOC storage include (i) litter production; (ii) litter quality; (iii) placing organic matter deeper in the soil either directly by increasing below-ground inputs or indirectly by enhancing surface mixing by soil organisms; (iv) increasing physical protection through either intra-aggregate or organic mineral complexes; and (v) microclimate change (Lemma et al 2006)
Summary
This study investigated the variation of soil organic carbon in four land cover types: natural and mixed forest, cultivated land, Eucalyptus plantation and open bush land. Soil organic carbon inventories are characterized by large uncertainties that may result from: (i) the large spatial variability of soil properties (such as large grain size, bulk density, soil thickness, and SOC concentration) and resulting SOC stock (Don et al 2011, 2007), (ii) the imperfect knowledge of the link between environmental conditions and SOC stocks, and (iii) the limitation of regional data sets (such as geological and soil maps) to represent the small variability of soil properties (Homann et al 1995) This is especially true in mountain environments, which are characterized by a greater geo-diversity than any other landscape (Slaymaker et al 2009; Korner 2003). Small changes in the SOC pool can have large implications for atmospheric CO2 concentrations (Simo et al 2010; Theurillat et al 1998)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
