Probing Acid Sulphate Soils for Sustainable Rice Production in Kuttanad: Challenges and Solutions

Acid sulphate soils of Kuttanad region in Kerala belongs to the category of problem soils, where crop production can be achieved through extensive soil management. Existence of jarosites, Fe, Al and Mn causes severe acidity in soil, while saline water intrusion due to nearness of sea can add salinity concerns. In addition, these soils were carbon rich with the existence of profound organic matter content, but biased with nutrient status of soil. Hence rice (Oryza sativa L.) is difficult to grow in this soil. Apart from the conventional practice of liming, use of organic amendments including rice husk ash, biochar, green manures and more could manage the acidic nature of soil to an extent and impart consistent nutrition without deterioration. Use of newly introduced genetic tolerant varieties, adaption of phyto-mining techniques and other critical land amendment practices can efficiently manage these soils for rice cultivation. The purpose of this review is to comprehend the soil properties and management strategies of acid sulphate soils of Kuttanad in order to produce rice as well as support further researches.