Abstract
There has been increased interest in soil organic carbon in recent times because of its role in carbon sequestration. Different parent materials affect soil properties and hence will influence how much carbon is sequestered by soil. The study was conducted in June 2019 to investigate soil carbon stock in forest soils with respect to their parent materials in three States in South-eastern Nigeria. Sampling was aided by the location map of the area and free soil survey method was used to locate sampling points. 0ne profile was dug in each location and described using the Food and Agricultural Organization guideline. A total of twelve soil samples were collected and analyzed for selected properties. Results showed that sand content was significantly higher in soils under coastal plain sands (851.96 g·kg−1) and was lowest in soils of Imo clay shale (605.60 g·kg−1). Clay content was higher in soils of Imo clay shale (277.34 g·kg−1) and was lowest in coastal plain sand (118.80 g·kg−1). Silt and clay had moderate variation in coastal plain sand (>15 ≤ 35%) and high variations in Asu River and Imo clay shale (CV > 35%). The soils studied were generally acidic with values ranging (3.52) in soils formed from coastal plain sand, followed by forest soils of Imo clay shale (3.64) and Asu river group (3.85). Soil organic carbon decreased with increase in soil depth in all soil parent materials studied. Mean values ranged from 6.14 g·kg−1 in soil underlain by coastal plain sand to 10.62 g·kg−1) in soils of Imo clay shale. Soil carbon sequestered under the three different parent materials ranged from 1575 - 4676.41 (g·cm−2). Also, soil depth had a notable impact on carbon sequestration with values ranging from 1529.42 - 4374.0541 (g·cm−2) and the thicker the horizon, the more carbon sequestered. Hence, the study concluded that more carbon is sequestered in the subsurface horizons of the soil pedons than in the epipedons.
Highlights
Some parts of the world are experiencing shortage of food due to climate change impacts (Aticho, 2013) and the rate of soil carbon decline in tropical soils is alarming because soil carbon is a principal factor in measuring the overall quality of a biome
The soils studied were generally acidic with values ranging (3.52) in soils formed from coastal plain sand, followed by forest soils of Imo clay shale (3.64) and Asu river group (3.85)
Bulk density differed in respect to parent materials studied and increased down the profile pits with mean values ranging from 1.14 in soils of coastal plain sand to 1.40 g∙cm−3 in soils derived from Asu river group
Summary
Some parts of the world are experiencing shortage of food due to climate change impacts (Aticho, 2013) and the rate of soil carbon decline in tropical soils is alarming because soil carbon is a principal factor in measuring the overall quality of a biome. Soil acts as a sink for carbon dioxide in exchange with the atmosphere in terrestrial ecosystems. According to Alexander et al (2015), more than 60% of soil carbon in the world is held in the soil (more than 40%) and the atmosphere (as carbon dioxide; 20%). Forest ecosystems store more than 80% of all terrestrial above-ground carbon and more than 70% of soil organic carbon (Batjes, 1996). Ahukaemere (2015) reported that conversion of native ecosystems like forests, wetlands and grasslands to agricultural uses, and continuous harvesting of plant materials caused significant losses of plant biomass and carbon, thereby increasing the carbon dioxide (CO2) level in the atmosphere. Resck et al (2008) observed that the use of native forests for cultivation is usually followed by a decline in organic carbon and soil structure deterioration Forest ecosystems store more than 80% of all terrestrial above-ground carbon and more than 70% of soil organic carbon (Batjes, 1996). Ahukaemere (2015) reported that conversion of native ecosystems like forests, wetlands and grasslands to agricultural uses, and continuous harvesting of plant materials caused significant losses of plant biomass and carbon, thereby increasing the carbon dioxide (CO2) level in the atmosphere. Resck et al (2008) observed that the use of native forests for cultivation is usually followed by a decline in organic carbon and soil structure deterioration
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
