Coal fly ash utilization in agriculture: its potential benefits and risks

Abstract

Over the past few decades there has been avid interest in developing the strategies for the utilization of Fly ash (FA). Major foci have been on its agricultural application. It is often economical to use FA as a soil amendment. The potential of FA as a resource material in agriculture is due to its specific physical properties like’s texture, water holding capacity, bulk density, pH etc., and contains almost all the essential plant nutrients. It can be used as in soil that cannot substitute the chemical fertilizers or organic manure it can be used in combination with these to get additional benefits in terms of improvement in soil physical characteristics, increased yields etc. The amount and method of FA application in soil would vary with the type of soil, the crop, grown, the prevailing agro climatic condition and also with the FA characteristics. Although, as an input material FA has many benefits for agriculture applications like, improvement of nutrient deficiency, effectively control various pests infesting etc., in contrast FA also contains number of toxic heavy metals and also have natural radioactivity materials in it. Therefore, proper attention should be given on some important areas related to FA utilization such as long term studies of impact of FA on soil health, heavy metal uptake, plant physiology and growth, crop quality, and continuous monitoring on the soil characteristics. While using FA in agriculture problem of heavy metal toxicity and leaching due to excess dose should also be kept in mind.