Clay Content, Clay Chemistry, and Carbon Sequestration from Piedmont Farmland: Part One of a Long Term Study
Abstract
Globally, soils hold more than three times the amount of carbon in the atmosphere and four times the amount of carbon stored in all living plants and animals combined, making it the largest carbon reservoir on the surface of the earth. In the past 300 years in North America, much of the topsoil has been lost to erosion due to poor agricultural practices and deforestation, creating the need to improve management of topsoil in farmland. The purpose of this project is to understand the processes that regulate carbon storage in soils in traditional piedmont farmland and how those processes can be used to increase carbon sequestration from the atmosphere and store carbon long term. We sampled several soil transects across a historic farm in Sharon, SC that has not been in crop rotation in several decades. The purpose was to create a baseline study of the existing carbon content and clay relationships on the farm in order to monitor the fluctuations of carbon storage on site long term at this location. The clay chemistry was dominated by kaolinite and montmorillonite. Clay content increased in the samples as expected from the upper elevations to the lower elevations of the farm. However, contrary to the traditional positive correlation between clay content and carbon content, the upper elevations contained higher concentrations of organic carbon than the lower. The likely reason for this is due to longer term amendments and tall grass growth during agricultural activities upslope vs at the lower elevations. Going forward, we hope to sample various plots of the farm that undergo new plantings and soil amendments in order to assess which methods increase carbon storage long term in that location.
Clay Content, Clay Chemistry, and Carbon Sequestration from Piedmont Farmland: Part One of a Long Term Study
Globally, soils hold more than three times the amount of carbon in the atmosphere and four times the amount of carbon stored in all living plants and animals combined, making it the largest carbon reservoir on the surface of the earth. In the past 300 years in North America, much of the topsoil has been lost to erosion due to poor agricultural practices and deforestation, creating the need to improve management of topsoil in farmland. The purpose of this project is to understand the processes that regulate carbon storage in soils in traditional piedmont farmland and how those processes can be used to increase carbon sequestration from the atmosphere and store carbon long term. We sampled several soil transects across a historic farm in Sharon, SC that has not been in crop rotation in several decades. The purpose was to create a baseline study of the existing carbon content and clay relationships on the farm in order to monitor the fluctuations of carbon storage on site long term at this location. The clay chemistry was dominated by kaolinite and montmorillonite. Clay content increased in the samples as expected from the upper elevations to the lower elevations of the farm. However, contrary to the traditional positive correlation between clay content and carbon content, the upper elevations contained higher concentrations of organic carbon than the lower. The likely reason for this is due to longer term amendments and tall grass growth during agricultural activities upslope vs at the lower elevations. Going forward, we hope to sample various plots of the farm that undergo new plantings and soil amendments in order to assess which methods increase carbon storage long term in that location.
