A review on biochar’s effect on soil properties and crop growth

Abstract

Intensive cultivation of agricultural soils causes soil degradation which emphasizes the need for sustainable soil management. Biochar, a pyrolysed carbon rich material has gained great interests among the researchers because of its eco-friendly benefits in addition to soil quality enhancement. Reviews on biochar, mainly confined to its environmental benefits like carbon sequestration and climate change. In this review, we summarize i) the effect of biochar application on soil properties (physical, chemical, biological), ii) remediation potential of biochar in heavy metal contaminated soils and iii) its impact on crop productivity. The properties of biochar like pH, greater surface area, cation exchange capacity, and nutrient content positively influences the soil properties and ultimately improves the soil fertility. Their effectiveness depends on biochar type, its dosage, soil type, etc. General trends from this review indicated that biochar as an effective amendment in acid soils than the alkaline or calcareous soils. Furthermore, the biochar effects are studied mostly under controlled conditions in laboratory, which needs to be validated under field conditions having varied soil types and agro-climatic zones.