Climate change and soil carbon sequestration have a complex interplay, with each influencing the other in several ways:

Impacts of climate change on soil carbon sequestration:

• Warmer temperatures: Increased temperatures can accelerate the decomposition of organic matter in the soil, reducing the potential for carbon storage.
• Changes in precipitation: Both droughts and increased rainfall can affect soil carbon sequestration. Droughts can limit plant growth and reduce the amount of carbon entering the soil. Heavy rainfall can lead to soil erosion, causing the loss of valuable carbon-rich topsoil.
• Shifting plant communities: Climate change may cause changes in plant communities, which can affect the amount of carbon entering the soil. For example, if forests are replaced by grasslands, soil carbon storage may decrease.

Role of crop residues in improving soil fertility and its relation to climate change:

• Crop residues as a carbon source: Leaving crop residues on the field acts as a direct source of carbon for soil microbes, promoting their activity and increasing soil organic matter. This leads to improved soil fertility by enhancing nutrient retention and soil structure.
• Reduced emissions: Crop residues can also help to reduce greenhouse gas emissions by protecting the soil from erosion and by suppressing the growth of weeds, which compete with crops for resources.
• Adapting to climate change: Improved soil fertility through crop residues can make crops more resilient to climate change by improving their ability to withstand drought, heat stress, and other extremes.

Overall, the interaction between climate change and crop residues on soil carbon sequestration and fertility is complex:

• Climate change poses challenges to soil carbon sequestration, but practices like leaving crop residues on the field can help to mitigate these challenges by increasing soil organic matter and promoting microbial activity.
• Improved soil fertility, with the help of crop residues, can also make crops more resilient to the impacts of climate change.

Here are some additional things to consider:

• The type of crop residue and the way it is managed can affect its impact on soil carbon sequestration. For example, chopping or shredding residues can increase their surface area and make them decompose more quickly, while burying them can promote longer-term carbon storage.
• The effectiveness of crop residues in mitigating climate change will depend on other factors such as land use practices, soil type, and climate conditions.

By understanding the complex relationship between climate change, soil carbon sequestration, and crop residues, we can develop more effective strategies for mitigating climate change and improving soil health.

Dr Murtadha Shukur thank you for your contribution to discussion

Climate change has the potential to impact the sequestration of carbon in the soil, a crucial process involving the capture and storage of atmospheric carbon in the ground. The presence of soil organic carbon (SOC) plays a pivotal role in maintaining soil health, fertility, ecosystem services, and supporting food production. Soils enriched with a higher carbon content are likely to exhibit increased productivity and enhanced capabilities for filtering and purifying.

The incorporation of crop residues into the soil contributes to improved soil structure, heightened organic matter levels, reduced evaporation, and the effective sequestration of CO2 in the soil. Implementing sound residue management practices in agricultural settings can yield numerous positive effects on soil quality.

Dr Abdelhak Maghchiche thank you for your contribution to discussion

Some soils have lost as much as 20 to 80 tons C/ha, mostly emitted into the atmosphere. Severe depletion of the SOC pool degrades soil quality, reduces biomass productivity, and adversely impacts water quality, and the depletion may be exacerbated by projected global warming. Especially in colder climates where decomposition is slow, soils can store or “sequester” this carbon for a very long time. If not for soil, this carbon would return to the atmosphere as carbon dioxide (CO2), the main greenhouse gas causing climate change. Carbon sequestration secures carbon dioxide to prevent it from entering the Earth's atmosphere. The idea is to stabilize carbon in solid and dissolved forms so that it doesn't cause the atmosphere to warm. Increasing soil carbon is accomplished in various ways, including: (1) reducing soil disturbance by switching to low-till or no-till practices or planting perennial crops; (2) changing planting schedules or rotations, such as by planting cover crops or double crops instead of leaving fields fallow; (3) managed grazing. Crop residue mulches improve soil aeration by promoting free exchange of gases between soil and atmosphere. This is facilitated by increased soil structural stability, total porosity and macro porosity, decreased surface crusting, which all contribute to improved overall soil drainage. The increased soil temperature at the time of residue burning not only kills the soil microbes but also depletes soil organic carbon level which is vital for keeping soil living.Crop residue incorporation into the soil also increases infiltration rate, saturated hydraulic conductivity and regulation of soil temperature. Soil organic carbon content and aggregate stability also found increased because of crop residue incorporation. Whether grown as pulses for grain, as green manure, as pastures or as the tree components of agro-forestry systems, a key value of leguminous crops lies in their ability to fix atmospheric nitrogen, which helps reduce the use of commercial nitrogen fertilizer and enhances soil fertility. Changes in precipitation: Both droughts and increased rainfall can affect soil carbon sequestration. Droughts can limit plant growth and reduce the amount of carbon entering the soil. Heavy rainfall can lead to soil erosion, causing the loss of valuable carbon-rich topsoil. Carbon sequestration secures carbon dioxide to prevent it from entering the Earth's atmosphere. The idea is to stabilize carbon in solid and dissolved forms so that it doesn't cause the atmosphere to warm.