Assessment of Conservation Agricultural Practices on Soil Nutrient’s Strati ication Ratio, Carbon Sequestration Rate, Management Indices and Crop Productivity in Southern Telangana India

The impending crisis for food production is the biggest threat in sustenance of soil resources due
to industrial farming practices adopted by multitudes of the farmers on all parts of the the world inclusive of
Southern Telangana Zone (STZ) in India. This can extensively degrade the soil if not substituted by soil
resource saving agricultural systems. This present experiment is implemented to assess the impact of
contrasting tillage practices and weed control tactics on soil quality parameters (SQPs) and monitor the grain
yield of maize after three-years in CA with cotton-maize-Sesbania rostrata cropping system. Three tillage
practices (main-plots); T 1 : CT(C)-CT(M)-fallow (NSr), T 2 : CT(C)-ZT(M)-ZT(Sr) and T 3 :ZT(C)+SrR-
ZT(M)+CR-ZT(Sr)+MS and weed control tactics (sub-plots) involved; W 1 -chemical weed control, W 2 –
Herbicide rotation, W 3 – Integrated weed management (IWM) and W 4 – single hand-weeded control in split-
plot design. Sampling of the soil in the 0 –15 and 15 – 30 cm, subsequent to harvesting of maize, was
analyzed for pH, EC, soil macronutrient’s availability, soil organic carbon (SOC), and computed for
stratification ratio (SR), C-sequestration rate (CSR), carbon management indices (CMI) and carbon retention
efficiency (CRE) duly following the standard procedures. The salient findings indicated that 9.1%, 15.3% of
SOC, 10.2%, 15.1% of available soil N, 12.2%, 19.6% of available soil P in the 0–15 cm and SR of 1.20 for
SOC, 2.0 – 6.5% of active carbon (C ACT ) pool in the 0 –30 cm was higher under T 3 relative to T 2 , T 1 ,
respectively. Similarly, 36.0%, 58.1% of cumulative CSR, 29.4%, 58.8% of CRE in the 0 –30 cm, and 17.0%,
30.3% of CMI in the 15–30 cm was higher T 3 compared to T 2 , T 1 , respectively. The C PSV was the dominant
contributor of SOC to total SOC over C ACT in the 0-30 cm soil layer. The 49.0% and 52.0% of C ACT pool was
observed to be higher under T 3 and single hand-weeded control, respectively. The T 3 had higher Kernel yield
(KY) of 8.4%, 11.6% in comparison with T 2 , T 1 , respectively. KY was also 23.4-43.1% greater under W 1 ,
W 2 , W 3 over W 4 . The ZT with crop residue retention (T 3 ), and IWM alternative to chemical weed control/
herbicide can slow-down the soil degradation process and enhance productivity in this zone.