Assessing Soil Fertility Dynamics and Carbon Sequestration Potential in Groundnut (Arachis hypogaea L.) Cultivation Areas of Sri Satya Sai District, Andhra Pradesh, India

Abstract

In 2021-2022, a study was conducted at the Agricultural Research Station in Anantapur, Andhra Pradesh, India, focusing on soil fertility changes and carbon storage potential in Sri Satya Sai district. A total of 300 soil samples were collected, 150 before and 150 after groundnut (Arachis hypogaea L.) cultivation in three blocks (i.e., Chennekothapalle, Ramagiri, and Roddam) of Sri Satya Sai District, Andhra Pradesh, India. Chennekothapalle exhibited a decline in pH from 6.83 to 6.53 after groundnut (Arachis hypogaea L.) cultivation, accompanied by a decrease in electrical conductivity (EC) levels from 0.22 to 0.18. Similarly, Ramagiri displayed a similar trend with a drop in pH from 7.03 to 6.63 and a decrease in EC from 0.22 to 0.20 dS/m. Roddam experienced a slight reduction in pH from 6.52 to 6.48 and a decrease in EC from 0.18 to 0.16 dS/m. Organic carbon (OC) content showed varying trends, with notable increases in Chennekothapalle (from 0.44% to 0.94%), Ramagiri (from 0.43% to 1.13%), and Roddam (from 0.3054% to 0.4454%) after cultivation. Nitrogen levels witnessed an increase in all three blocks, Chennekothapalle rising from 141.3 to 171.3 kgs/ha, Ramagiri from 162.11 to 192.11 kgs/ha, and Roddam from 129.44 to 154.44 kgs/ha. Additionally, Posphorus levels increased in Chennekothapalle (from 16.76 to 19.76 kgs/ha), Ramagiri (from 13.62 to 18.62 kgs/ha), and Roddam (from 30.24 to 35.24 kgs/ha) after cultivation. Similarly, Potassium levels showed increases in Chennekothapalle (from 159.07 to 184.07 kgs/ha), Ramagiri (from 161.04 to 195.04 kgs/ha), and Roddam (from 154.49 to 174.49 kgs/ha), indicating distinct patterns of soil fertility dynamics across these regions. In Chennekothapalle, the soil organic carbon content (TOC) increased from 0.004% to 0.009%, and there was a substantial rise in soil carbon stock (SCS) from 18.11 to 39.37 kgs/m². Carbon turnover, measured through mean CO2 levels, increased from 160.45 gms to 343.7 gms, and the Carbon Sequestration Potential (CSP) was 6900 Kgs. In Ramagiri, TOC saw an increase from 0.004% to 0.011%, with SCS improving from 30.92 to 37.38 kgs/m², indicating greater soil carbon storage. A significant rise in CO2 levels from 158.69 gms to 415.3 gms was observed, and CSP was 7700 Kgs. In Roddam, TOC increased from 0.003% to 0.004%, and SCS rose from 20.24 to 30.06 kgs/m², signaling improved soil carbon stocks. CO2 levels increased from 111.98 gms to 163.3 gms, reflecting enhanced carbon turnover, and remarkably, CSP was 3150 Kg. In comparing the three blocks, it's evident that Ramagiri exhibited the most substantial increase in soil fertility and carbon sequestration potential. While Chennekothapalle is showing significant improvements, Roddam experienced relatively modest changes in all parameters.