Soil Carbon Sequestration - A Biological Negative Emission Strategy

Soil carbon sequestration is one of three major ways of carbon dioxide removal and storage through terrestrial ecosystem management.

Soil carbon sequestration depends on better management methods that enhance the amount of carbon stored as soil organic matter, especially in crops and grazing fields.

These carbon sequestering strategies work by increasing the input rate of plant-derived residues into soils and/or decreasing the turnover rates of organic carbon stocks already present in the soil.

Increases in soil organic matter/carbon content are particularly favorable regarding soil health, fertility, and carbon dioxide removal capability.

Well-known, tried-and-true procedures or "best management practices" for increasing soil carbon stocks are among the strategies for increasing soil carbon stocks.

COPYRIGHT_SZ: Published on https://stationzilla.com/soil-carbon-sequestration/ by Suleman Shah on 2022-08-04T19:04:00.809Z

A second group comprises frontier technologies, which have major technical and economic obstacles today but have the potential for higher sequestration in the long run and financial incentives.

Management Techniques For Increasing Soil Carbon Storage And Net CO2 Removals

According to the National Academies study, soil carbon sequestering management approaches are classified into two major groups.

The first group contains recognized, established conservation management methods and strategies that may improve soil carbon on current crops.

The second category is "border technologies," which are systems or practices that face severe technical and economic constraints.

With the right incentives, such best management practices may be promptly implemented to raise soil carbon stock in the short run.

Conventional Soil Carbon Sequestration Techniques

Numerous field tests and comparative observations have shown conventional conservation measures that may lead to increased soil carbon reserves.

Crop Rotations And Cover Cropping: Farmers may choose various agricultural options that boost soil carbon inputs. Farmers in many arid areas leave croplands fallow yearly to save soil moisture and stabilize grain output. In such systems, intensifying and diversifying crop rotations may enhance average annual carbon imports. Adding 2-3 years of perennial hay/forage crops to rows in moister settings will improve carbon inputs from fine roots and raise soil organic carbon levels.

Manure And Compost: Organic matter additions like compost and manures may boost soil carbon levels. One challenge in determining the total effect of organic amendments on net CO2 reductions is that modifications often originate "off-site." A thorough life cycle assessment is required to account for carbon accrual and net greenhouse gas emissions reductions. Composting is a potentially appealing approach that requires more research to determine the entire spectrum of environmental costs and benefits.

Tillage: Farmers use tillage to manage crop wastes and prepare seed beds for crops. Tillage technology and agronomic practice advancements have enabled farmers to minimize tillage frequency and intensity. Some farmers have abandoned tillage, a practice known as "no-till." The Global Warming Potential of no-till systems is 66% lower than that of traditionally tilled systems. One-time deep inversion tillage in humid and subhumid croplands may be particularly successful in promoting a considerable rise in soil carbon stores. Burial of carbon-rich surface soil has been shown to delay decomposition significantly. "Traditional" carbon sequestration procedures can potentially create new carbon stores in surface soil layers quickly.

Perennial Grasses and Legumes Conversion: Croplands converted to perennial vegetation (grasses and trees) have increased carbon inputs and soil disturbance. The Conservation Reserve Program in the United States compensates farmers for retiring marginal and erodible croplands. Long-term field research has shown that accumulations may last for decades.

Rewetting of Organic Soils: Organic soils are peat and muck-derived soils whose total bulk is mainly composed of organic materials. Organic soils do not experience saturation in the same manner as mineral soils do. High CO2 and N2O emissions may be reduced by removing organic soils from cultivation and restoring hydrological conditions.

Grazing Land Management: Non-forested grazing areas in the United States are usually classified into two types: pastures and rangelands. Increasing soil organic carbon mostly depends on increasing carbon inputs from plant roots and residues. Ranchers may do this by regulating the loss of plant biomass through grazing or improving fodder production via enhanced species, irrigation, and fertilizer. Intensive grazing methods use high animal stocking rates for short periods on a pasture. Various terminologies are used, such as rotation grazing, mob grazing, and adaptive multi-paddock grazing. Some research indicates that adaptive multi-paddock grazing systems significantly impact soil production and physical qualities.

Non-Conventional Soil Carbon Sequestration Techniques

Non-forested grazing areas in the United States are generally classified into pastures and rangelands.

Increasing soil organic carbon depends mainly on increasing carbon inputs from plant roots and residues.

Ranchers may do this by regulating the loss of plant biomass through grazing or improving fodder production via enhanced species, irrigation, and fertilizer.

Intensive grazing methods use high animal stocking rates for short periods on a pasture.

Various terminologies are used, such as rotation grazing, mob grazing, and adaptive multi-paddock grazing.

Some research indicates that adaptive multi-paddock grazing systems significantly impact soil production and physical qualities.

• Biochar: Biochar is a carbon-rich solid made from biomass by pyrolysis, a thermochemical conversion process. Many fire-prone environments, such as grasslands, savannas, and forests, include biochar in their soils. It may account for up to 35% of the total organic carbon in these systems. Biochar is a carbon stock that, once applied to earth, has a long shelf life. Biochar additions may potentially interact with existing organic matter in soils. These interactions might affect soil water retention, hydration, pH, or nutrient availability. The principal influence of biochar on greenhouse gaseous balance is connected with the biochar's long-term storage when applied to the soil. There is a growing agreement that biochar treatments assist in lowering N2O emissions on average. The reduction depends on the biochar life cycle, biomass feedstock production, and harvesting emissions.
• Deeper and Larger Root Annual Crops: future crops may have higher soil carbon inputs and deeper root dispersion, which will boost soil carbon storage. Kell presented an argument in 2012 for the possibility of directing plant breeding efforts toward generating types for our key grain crops with more carbon delivery to roots and deeper root spread. In present agriculture, widespread adoption of annual crop genotypes might result in soil carbon stock increases of 0.5 gt co2/ha/year.
• Perennial Grain Crops: perennial crops would eliminate the requirement for tillage, as well as the detrimental consequences on soil organic carbon stocks and soil erosion. More extensive and deeper root systems may also help to prevent nitrate leakage into streams. Perennial grains might sequester roughly one tc/ha/y over the years. When grown on a large scale, perennial grains have unclear economic viability. Intermediate wheatgrass yields are approximately 1,000 kg/ha, which is 5-10 times lower than annual wheat yields. Other difficulties include grain cracking, lodging, and reduced seed size. Perennial grains promise to expand the range of ecosystem services given by agriculture. Still, more effort has to be made to develop cultivars with consistent regrowth and acceptable grain yields. The possibility for combined grain and forage production opens the door to the successful commercialization of perennial grain crops.

Soil CO2 Sequestration And Removal Potential

There are different estimates of how much carbon can be stored in soils worldwide and in the US.

Most estimates are based on large amounts of data about the total area by land use type, which are then grouped into broad climate categories.

Estimates worldwide are close to each other, suggesting that a technical soil carbon sequestration potential of 2–5 Gt CO2 per year is possible.

There seems to be good support for an estimate of 4–5 Gt CO2 per year for widespread adoption of a wide range of best management practices (BMPs) for soil carbon sequestration on grassland and cropland around the world.

These carbon storage rates could be kept up for only a short time, on 2–3 decades.

Most estimates are based on large amounts of data about the total area by land use type, which are then grouped into broad climate categories.

Assessments at the lower end of this range take into account either a smaller amount of land or a smaller number of practices.

There is good evidence that a wide range of BMPs could save as much as 4–5 Gt CO2 per year if everyone used them.

People Also Ask

What Is The Process Of Carbon Sequestration?

The method of absorbing and storing atmospheric carbon dioxide is known as carbon sequestration. It is one way of decreasing carbon dioxide levels in the atmosphere to slow global climate change.

What Are Two Benefits Of Carbon Sequestration In Soil?

Tilling prepares land for new crops and helps manage weeds by breaking up the soil, but it also releases a lot of stored carbon.

According to supporters, farming techniques that store more carbon may boost soil health and food output.

How Do You Sequester Carbon Into The Soil?

Plants sequester carbon in soil via photosynthesis, which may be stored as soil organic carbon.

Although agroecosystems may deteriorate and deplete soil organic carbon levels, the carbon deficit provides an opportunity to store carbon via novel land management methods. Carbonates may also be stored in the soil.

How Much Carbon Do Soils Sequester?

Soils are expected to store roughly 20 Pg carbon every 25 years, accounting for more than 10% of human emissions.

At the same time, this method delivers significant advantages for soil, agricultural, and environmental quality, erosion and desertification avoidance, and bio-diversity promotion.

Final Words

There is compelling scientific evidence that agricultural soils will serve as a large carbon sink in the following decades.

Several carbon sequestering strategies may be used, and the optimal solutions differ depending on climate, soil, and agricultural practices.

The strong policy might be implemented right once to kickstart a worldwide effort to boost soil carbon sequestration using current technology.

Many nations may apply negative emission solutions in agriculture while improving soil health and resilience.

This would promote and support world-scale actions to reduce average global temperature rises to 2°C.

About The Authors

Suleman Shah - Suleman Shah is a researcher and freelance writer. As a researcher, he has worked with MNS University of Agriculture, Multan (Pakistan) and Texas A & M University (USA). He regularly writes science articles and blogs for science news website immersse.com and open access publishers OA Publishing London and Scientific Times. He loves to keep himself updated on scientific developments and convert these developments into everyday language to update the readers about the developments in the scientific era. His primary research focus is Plant sciences, and he contributed to this field by publishing his research in scientific journals and presenting his work at many Conferences. Shah graduated from the University of Agriculture Faisalabad (Pakistan) and started his professional carrier with Jaffer Agro Services and later with the Agriculture Department of the Government of Pakistan. His research interest compelled and attracted him to proceed with his carrier in Plant sciences research. So, he started his Ph.D. in Soil Science at MNS University of Agriculture Multan (Pakistan). Later, he started working as a visiting scholar with Texas A&M University (USA). Shah’s experience with big Open Excess publishers like Springers, Frontiers, MDPI, etc., testified to his belief in Open Access as a barrier-removing mechanism between researchers and the readers of their research. Shah believes that Open Access is revolutionizing the publication process and benefitting research in all fields.