Abstract
The present study was based on the hypothesis that "the use of classical farming techniques is the cause of emission of greenhouse gases (GHGs) in the study area, which can be mitigated by employing smart agricultural practices (SAPs)". The study comprises experimental trials, which were carried out over two consecutive years (2020-2021) on two experimental areas (site 1: Koel, site 2: Moel) in District Bhimber of Azad Jammu and Kashmir, Pakistan. Wheat cv. Punjab-2018 was used in the experiment. The experiment was performed in a split-plot factorial arrangement with the main experimental plot bisected into two subplots. Within the two halves of the experimental plot, one side experienced the original tillage practice (PT--by ploughing at a depth of 4-6 cm; HT--by harrowing at 12-15 cm; NT--no tillage, of subsoil or soil ploughing). The subsoiling technique applied included subsoiling ploughing tillage (SPT), subsoiling harrow tillage (SHT), and subsoiling of no-tillage (SNT). Subsoiling was performed by means of ploughing land utilizing a vibrating subsoil trowel to a depth of 14 to 14.5 inches. As a result, each subplot was divided into three replicates. So, a total of six replicates, each 35 m in length and 4 m in width were chosen for the experiment. The results depicted that the influx of COx uptake increased in all subsoiling treatments: that is, SPT, SHT, and SNT. The uptake of COx was comparatively lower in HT, RT, and NT. In the same manner, GWP for NOx was recorded to increase when the soil was subjected to subsoiling, that is, HTS, RTS, and NTS. Along with this, the trend of soil temperature and soil content also fluctuated with R-2 = 0.78 at p < 0.01 from February to April and R-2 = 0.66 from December to January, which shows that SAP causes higher emission of NOx and more uptake of COx. Subsoiling maintains soil moisture content (SMC) and soil organic carbon (SOC), which allows limited release of NOx from soil, maintaining the soil nitrogen content. In the case of SOC and pH, it was found that higher pH causes reduced absorption of COx into soil and NOx emission from soil while higher SOC causes more absorption of COx into soil and more emission of NOx. The application of smart agriculture in the form of subsoiling leads to an increase in the yield of wheat crops and is recommended in agriculture in the context of climate change.