CIRS Blog about Rural California
The University of Florida's Institute of Food and Agricultural Sciences (UF/IFAS) is a federal, state, and county partnership dedicated to developing knowledge in agriculture, human and natural resources, and the life sciences and to making that knowledge accessible to sustain and enhance the quality of human life.
Carbon Sequestration in Grazing Land Ecosystems1
Maria Silveira, Ed Hanlon, Mariana Azenha, and Hiran M. da Silva2
This publication provides basic information about the important role of native and improved pastures (referred to as grazing land) in sequestering carbon from the atmosphere. Because of the relatively high sequestration rates and extensive area, grazing land represents an important component of terrestrial carbon dioxide (CO2) offset and is a significant sink for long-term carbon sequestration and greenhouse gas mitigation. This publication contains information for stakeholders, students, scientists, and environmental agencies interested in enhancing ecosystems services provided by grazing lands.
Global Carbon Cycle
The global carbon cycle consists of complex processes that control the movement of carbon between the atmosphere, land, and oceans. Although natural processes dominate the carbon cycle, human-induced activities can also alter these carbon transfers. In the atmosphere, carbon is mainly present as carbon dioxide (CO2). Large amounts of carbon are also present in the soil, primarily as soil organic matter. Soil organic matter plays a key role in determining soil quality and its potential to produce food, fiber, and fuel. During the past two decades, the global carbon cycle has received significant attention because of its role in global climate change.
Two important global topics are the rising atmospheric CO2 concentrations caused by human-induced activities (primarily combustion of fossil fuels) and the potential effects on climate change. In addition to CO2, increased atmospheric concentrations of nitrous oxides (N2O and NO) and methane (CH4) are also believed to cause global warming. Carbon dioxide, nitrous oxides, and methane (also known as greenhouse gases) can trap heat in the atmosphere and contribute to global warming. Levels of several important greenhouse gases have increased by 25% since large-scale industrialization began approximately 150 years ago, and this increase is primarily caused by energy use.
Plants remove carbon from the atmosphere during photosynthesis, a process done without human intervention. However, to address the contributions made by humans, the carbon must be stored or sequestered. Typically, carbon in plants undergoes several conversions. Some conversions are rapid, such as the addition of fresh plant material to the soil, while others may take long periods of time. For example, a large amount of carbon is already sequestered in our soil.