Evaluating soil quality and bioefficacy study of Cajanus cajan L. in coal mine-degraded land

Abstract

Surface mining activities in past and recent times have resulted in the existence of a number of overburden dumps (mine spoils) through excavation and deposition of removed soil and rock debris. These spoils require environmental stabilization/restoration through proper revegetation. The present study was undertaken to examine the influence of various amendments to soil properties and the growth and yield of Cajanus cajan L. cultivation in mine-degraded soils. An experiment was conducted with nine combinations of various amendments to C. cajan L., a widely cultivating legume in India for its highly nutritious seeds. The physicochemical and biological properties of mine spoil before and after treatment were analyzed. Plant growth in terms of seed germination, shoot length, root length, total dry weight, number of leaves, root nodules, and yield components were measured. The experimental results revealed that combination of C 3 (mine spoil amended with biofertilizers, farmyard manure, and fly-ash) and C 8 (mine spoil amended with biofertilizers, vermicompost, and fly-ash) showed the best results to support vegetation. Percentage increases in crop growth, grain yield, and soil nutrients compared to the control were also observed. With C 3 , grain yield was found to be maximum (79.66 g/pot), with an increase of 215.95%. Number of pods per plant was found to be 27.50 and 27.75 in C 3 and C 8 treatments, respectively. All the physicochemical and biological properties were enhanced significantly (P ≤ 0.05) in all the combinations compared to the untreated control. C 8 exhibited significantly higher concentrations of nitrogen, phosphorous, and potassium of about 67.55, 5.16, and 58.33 mg kg -1 , proving it to be good at improving soil quality.