Textural Influence on Moisture Holding Capacity of Soil and Fly Ash: A Laboratory Investigation

Soil moisture represents the quantity of water contained within the soil matrix and plays a crucial role in determining its suitability as a growing medium for plants. The capacity of a soil to retain and transmit water influences its storage capabilities and percolation behavior, thereby affecting plant development and productivity. Understanding the soil water retention characteristics is essential for assessing the amount of water accessible to crops. Since water dynamics in soils - such as infiltration, root absorption and evaporation - are governed by energy gradients, these interactions are typically described in terms of soil water potential. In light of this, a laboratory investigation was undertaken at the Department of Soil Science and Agricultural Chemistry, Faculty of Agriculture, Annamalai University, Annamalai Nagar. The aim was to evaluate the moisture retention properties of soils with varying textures and different fly ash samples using a pressure plate apparatus. The findings indicated that fly ash demonstrated a higher moisture retention capacity than soils. Among the soil types, clay loam exhibited greater water-holding ability in comparison to loam and loamy sand. Additionally, a notable decline in moisture retention was observed across all samples as the applied pressure increased from 0.3 to 15 bars.