Phytochemical analysis and HPTLC finger-printing profile of roots of Alstonia scholaris (L.) R.Br (Saptaparṇa)

Abstract

A study was conducted in four major soils of Kerala namely red loam (Vellayani series), laterite (Trivandrum series), coastal sandy (Kazhakuttam series) and forest soil (Kallar series) to assess the impact of different agricultural land use systems on soil carbon dynamics. Surface soil samples (0-15 cm depth) were collected and analyzed for soil properties and carbon pools following standard procedures and carbon stock in soil was also calculated. The results indicated that various land use categories had a significant effect on soil properties and carbon pools. The soil organic carbon values ranged from 2.96 to 9.93 g kg-1. The highest value was recorded under rubber land use in Kallar soil, which is significantly higher (about 3.6 times) than the coconut land use in Kazhakuttam soil which had the least value. The highest carbon stock of 23.02 kg m-2 was recorded in rubber land use in Kallar soil. The total particulate organic carbon concentration was also found to be the highest in rubber land use (Kallar series). The highest concentrations of labile carbon were found in soils from coconut plantation site (2516 mg kg-1), followed by rice field (2187 mg kg-1), whereas the lowest concentration was detected in homestead site (940 mg kg-1). Hot water soluble carbon in soil ranged between 18.14 and 76.45 mg kg-1 Cumulative amount of carbon mineralized in 15 days of incubation ranged from 2.86 to 6.39 mg C kg-1 soil.