Carbon is the most important chemical element in all living things in the universe. Unlike most elements, it can form several types of bonds to form different compounds that are necessary for survival. Besides being an essential building block of life, carbon is also a component of all plants and animals on the planet. But there’s a lot more about carbon that may not be known to many, especially when it comes to agriculture.
Carbon is critical to soil function and productivity, and remains a key contributor to healthy soil conditions which promote plant growth and quality food production. During the photosynthesis process, plants draw carbon out of the air to create fuel – glucose and other sugars – to maintain soil structures and support plant growth. What is not needed for growth is released through the roots to feed soil organisms, whereby the carbon is humified or rendered stable. Being the main component of soil organic matter, carbon helps improve water-retention capacity of the soil as well as its structure and fertility.
Soil management and other agriculture practices play a crucial role in whether the carbon remains in the soil or is released to the atmosphere. When released into the atmosphere, carbon can contribute to one of the most critical issues facing the world – climate change and global warming. Agricultural practices can leave an impact on both the amount and the composition of soil organic carbon, thus affecting soil’s physical, biological, and chemical condition which together contributes to soil health. Therefore, farm practices that affect soil carbon will also impact agricultural productivity, the soil’s ability to deal with extreme weather conditions, and the carbon cycle itself.
WHAT EXACTLY IS SOIL ORGANIC CARBON?
Soil organic carbon (SOC) is a measurable component of the soil organic matter which affects the chemical and physical characteristics of the soil, such as such as nutrient availability, moisture holding capacity, water infiltration ability, and the biological activity of microorganisms. Soil organic matter (SOM) is composed of microbes present in the soil including bacteria and fungi, tissues from dead plants and animals, faecal waste, and materials formed from their decomposition. All the organic compounds that make up organic matter are highly enriched in carbon. That said, SOM turnover plays a crucial role in soil functions, ecosystem functioning and global warming.
IMPORTANCE OF CARBON SEQUESTRATION IN AGRICULTURE
While the agricultural sector is considered the biggest contributor to GhG (Greenhouse Gas) emissions due to its ability to impact the carbon cycle on a large scale through the release of carbon during various farm practices, farmers are showing a growing interest in retaining and increasing soil organic carbon for individual and environmental benefits. Agricultural lands and plants can act as huge carbon sinks for their ability to sequester greenhouse gasses such as carbon dioxide.
The increase in the levels of carbon dioxide and other harmful green house gases like methane and nitrous oxide causes extra heat to get trapped in the atmosphere, raise temperatures and warm the climate, increasing the rate of global warming. Global warming and climate change have the potential to stress ecosystems with serious alterations to the environment, such as temperature rises, water shortages, increased wildfires, drought, weed and pest outbreaks, crop diseases, intense storm damage and salt invasion, decreased sustainability of agricultural and food production systems, just to name a few. Furthermore, global warming impacts the air quality and causes the pollution to rise, eventually impacting human and animal health.
With agricultural sustainability and productivity significantly reliant on soil organic carbon and carbon cycling, it is important to implement agriculture and management practices to efficiently manage soil and fields. These practices mainly focus on using the potential of soil to sequestrate and store carbon, reducing carbon loss into the atmosphere and enhancing SOM levels to mitigate the effects of global warming and climate change. The aim is to create more sustainable and fertile farmlands and healthier ecosystems while creating better income opportunities for farmers and agribusinesses alike.
Here are some farm management practices that can improve soil organic carbon and help combat climate change and global warming by reducing carbon loss into the atmosphere.
- Conservation Tillage Practices:
Using no-tillage methods for cultivation helps store and increase soil organic carbon while keeping the physical stability of the soil intact. When combined with residue management and manure management, reduced-till systems can significantly increase soil organic carbon over time.
- Cover Crops
Cover crops can promote soil aggregation and improve the ability of soils to store carbon by adding both above-ground and root biomass. They also reduce the impact of rain drops on the soil surface of a farmland, decreasing the risk of soil erosion and the resulting loss of carbon with soil particles. Cover crops help enhance nutrient cycling by storing nutrients from manure, organic nitrogen or underutilised fertilisers until they can be used by the following years’ crops. This results in improved soil health over time.
- Crop Selection
Use perennial crops that automatically grow back after harvest, eliminating the need for yearly planting. These crops increase carbon sequestration through root and litter decomposition post-harvest. Planting high residue annual crops can also help minimise net carbon loss into the atmosphere from cropping systems.
Climate change is an ongoing challenge for farmers and agribusinesses alike. Soil carbon management is important for managing soil structure and health, increasing crop yields and reducing soil loss while also protecting the environment. Our KG2 team can assist you with best carbon farming solutions in Australia and data-driven advisory services that will help you make informed decisions about soil and farm management and create a sustainable and profitable agriculture business.