Performance Evaluation of Real-time Soil pH Measuring System in Different Tillage Conditions

Soil pH is affected by various soil-forming factors such as parent material, time, relief or topography, climate, mineral content, rainfall, soil texture and organisms, etc. Considering the extent of precision agriculture in India, the present study was planned to evaluate the performance of developed real-time soil pH measuring system in field and study the effect of tillage and residue management on soil pH measurement. The developed system was operated in field in three tillage treatments i.e. conventional tillage (T1), no tillage (T2) and residue incorporation (T3) and at three forward speeds of 1.1, 1.5 and 2.9 km/h at periodic interval of 10, 20, 30, 40, 50 and 60 days, respectively. The soil pH in field measurement varied from 7.98–8.18 in T1, 7.60–7.94 in T2 and 8.01–8.21 in T3 throughout the experiment. The error (%) in measuring soil pH varied from 0.12%-1.75% in T1, 1.37%-3.78% in T2 and zero to 1.37% in T3 throughout the experiment. The tillage treatments had significant effect on soil pH measurement and error (%). The error (%) was more in T2 because the soil was untilled, unpulverized and presence of clods in the field caused inappropriate engagement of pH sensor with the topsoil. The results showed that field had variable soil pH and the developed system was capable to measure the spatial variation in soil pH in the field.