Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis of raw and composted coir pith as soilless media

Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis of raw and composted coir pith as soilless media Anbarasu Mariyappillai Kumaresan Marappan Manibharathi Sekar Vijai Ananth Arumugam

Coir pith, an abundant agro-industrial by-product of coconut processing, is increasingly explored as a sustainable alternative to peat-based substrates in soilless cultivation. However, its direct application is constrained by a high carbon-to-nitrogen (C: N) ratio, the complexity of lignocellulose, and potential phytotoxicity. Composting is commonly employed to improve its physicochemical properties and enhance its usability as a growing medium. The present study aimed to evaluate changes in chemical composition, elemental characteristics, and functional group properties of raw and composted coir pith using advanced analytical techniques. Composting was carried out for 30 days using a layered method with microbial inoculation (Pleurotus sajor-caju-based formulation) and urea supplementation. Results indicated a reduction in C:N ratio from 70.7:1 to 32.7:1 and a decrease in total organic carbon from 59.39% to 30.80%. Nutrient contents increased, with total nitrogen rising from 0.84% to 0.94%, phosphorus from 0.02% to 0.86%, and potassium from 1.84% to 1.96%. SEM analysis revealed structural degradation and altered pore architecture, while EDX showed a reduction in carbon (from 71% to 60%) and an increase in oxygen (from 25% to 32%). FTIR analysis indicated qualitative changes in functional groups associated with lignocellulosic components. These findings demonstrate that composting induces significant physicochemical and structural modifications in coir pith, suggesting its potential suitability as a soilless substrate. However, the contribution of external nitrogen inputs and the lack of plant-based validation highlight the need for further investigation.
06 21 2026 939 945 http://creativecommons.org/licenses/by-nc/4.0 10.31018/jans.v18i2.7673 https://journals.ansfoundation.org/index.php/jans/article/view/7673 https://journals.ansfoundation.org/index.php/jans/article/download/7673/3185 https://journals.ansfoundation.org/index.php/jans/article/download/7673/3185