Fly Ash for Agriculture: Implications for Soil Properties, Nutrients, Heavy Metals, Plant Growth and Pest Control

Abstract

Annual fly ash production ranges from 2 MT in the Netherlands to 112 MT in India, whereas fly ash utilisation ranges from 100% in the Netherlands to 38% in India. Over the past few decades there has been interest in developing strategies to use fly ash in agriculture. It is indeed economical to use fly ash as a soil amendment. Reviews on fly ash in agriculture are scarce. The potential of fly ash as a resource material is due to its specific physical properties such as texture, water holding capacity, bulk density, and pH. Moreover fly ash contains almost all essential plant nutrients. Fly ash can be used as an amendment in soil. Fly ash can improve soils physical and chemical properties, reduce pest dammade on crops and increase crop yields. The amount and method of fly ash application to soil depend on the type of soil, the crop grown and fly ash characteristics. Besides positive effects fly ash may contain also toxic metals and radionuclides. Therefore use of fly ash should be done with care, notably by taking into account the uptake of metals by plants. This chapter describes the properties of fly ash, and the effect of fly ash on soil properties, nutrients, heavy metals uptake by plants, yields and pest control.