Comparative Study of Soil Properties and Organic Matter Fractions in Organic and Conventional Farms of Kerala, India

Aims: Assessing various soil properties as influenced by organic farming in the selected certified organic and conventional farms of Kerala.

Study Design: Ten pairs of certified organic farms and nearby conventional farms were identified from different agroecological zones of Kerala and were analysed for physical, chemical and biological properties.

Place and Duration of Study: The research was conducted at College of Agriculture Vellayani, between December 2020 – June 2021.

Methodology: Soil samples were collected from these farms and analyzed for soil physical, chemical and biological properties, organic carbon, total nitrogen, C: N ratio and organic matter fractions.

Results: Organic farms exhibited lower bulk density (1.15 Mg m-3) and higher values in porosity (41.32%), water holding capacity (52.68%), mean weight diameter (1.87%), and water stable aggregates (73.59%) compared to conventional farms. Additionally, organic farms were found to be higher in electrical conductivity (0.09 dS m-1), cation exchange capacity (5.98 C mol(p+) kg-1), total organic carbon (7.59%), total nitrogen (0.46%), and C:N ratio (16.14) in comparison to conventional farms. The concentrations of fulvic acid, humic acid, and humin are also greater in organic farms, with mean values of 5.45%, 3.56%, and 0.47%, respectively.

Conclusion: Organic farming has a significant role in improving the physical, chemical and biological properties of the soil and also total carbon, total nitrogen and the organic matter fractions.