SUSTAINING ORGANIC CARBON IN FARMS

Organic carbon is the cornerstone of healthy soils, essential for sustainable farming and agricultural productivity. Effective management of organic carbon not only improves soil health but also fosters self-reliance for farmers and ensures long-term resilience against climate change and water scarcity.

C:N Ratio

The Carbon to Nitrogen (C:N) ratio is a crucial factor in composting and soil management. It measures the proportion of carbon to nitrogen in organic materials. The ideal C:N ratio for composting is around 25-30:1. A balanced C:N ratio ensures efficient decomposition and nutrient release. 

Current C:N Ratio in Indian Soils: Typically ranges from 10:1 to 12:1 in natural soils, often indicating a need for more carbon-rich organic inputs to balance nitrogen. 

Improving the C:N Ratio: To achieve a balanced ratio, adjust the compost materials: Add Carbon-Rich Materials: Include dry leaves, straw, or sawdust to raise the C:N ratio.

Add Nitrogen-Rich Materials: Include green plant residues, manure, or food scraps to lower the C:N ratio. Studies show that maintaining a C:N ratio of 25-30:1 during composting leads to a more effective decomposition process, with improvements in soil structure and fertility (Source : FAO Soil Health Guidelines).

STRATEGIES TO IMPROVE ORGANIC CARBON FROM 0.5% TO 3%
Reduced Tillage Practice: Minimizing soil disturbance through methods like no-till farming gradually increases soil organic carbon (SOC) by 0.1-0.2% per year. This approach preserves soil structure, reduces erosion, and enhances carbon sequestration. To implement this, use direct seeding techniques and avoid significant mechanical soil disturbances. 
Agroforestry: Integrating trees and shrubs into agricultural systems can enhance SOC by up to 0.5% over a decade. Agroforestry increases biodiversity, improves soil health, and enhances water retention. Plant trees or shrubs alongside crops or pasture lands and maintain them over time to reap these benefits.
Permanent Cover Crops: Using perennial plants for continuous soil cover builds SOC and reduces soil erosion over time. Establishing perennial crops like clover or alfalfa provides continuous soil coverage, reduces erosion, and improves SOC. Maintain these cover crops along with the primary crops, over multiple seasons for maximum impact. It is established that leaving land fallow impacts negatively on the microbiome population, and then needing rebuilding of the same. 
Long-Term Green Manuring: Regularly incorporating nitrogen fixing (mostly dicots) crops over several seasons significantly increases SOC. Rotate such crops each season and incorporate them into the soil to sustain these benefits.
Integrated Nutrient Management: Combining organic and inorganic fertilizers for balanced soil nutrition sustains SOC levels and improves soil health. Apply enriched organic compost and minimize use of chemical fertilizers based on soil test recommendations to optimize nutrient use and support long-term soil fertility. 
Perennial Grasses: Growing grasses that persist for multiple seasons builds SOC and reduces erosion. Establishing and managing perennial grass species like switchgrass or fescue maintains soil cover, improves SOC, and supports long-term soil health. This can be followed on bunds and boundaries.
                       
GOVERNMENT INITIATIVES AND RECOMMENDATIONS
Soil Health Card Scheme: To monitor soil health and provide recommendations for organic matter enhancement. It helps farmers understand their soils nutrient status and adopt appropriate measures to improve soil health and fertility. 
National Mission for Sustainable Agriculture: This mission promotes practices like cover cropping, crop rotation, and the use of organic amendments to improve soil health. These sustainable practices help enhance soil organic carbon, improve soil structure, and boost agricultural productivity. 
Composting Initiatives: State governments are encouraging composting of organic waste to produce nutrient-rich compost, which can be added to soils. Composting helps recycle organic matter, improve soil health, and reduce waste.
Natural Farming: This emphasizes use of on-farm natural inputs and processes to improve soil health and reduce reliance on external inputs. It promotes the use of biofertilizers, organic mulches, and other natural practices to enhance soil organic carbon and support sustainable agriculture.

Maintaining organic carbon in farms is vital for self-reliance, soil health, and sustainable agricultural productivity. Strategies such as composting, cover cropping, reduced tillage, crop rotation, agroforestry, and biochar application can effectively increase soil organic carbon (SOC) levels from 0.5% to 3% – we lose SOC faster than we can recover it!. Implementing crop rotation and cover cropping with specific carbon-sequestering crops, including legumes, deep-rooted plants, and perennials, can significantly enhance soil organic matter, improve soil structure, and ensure long-term soil health.