Geoclimatic modelling of pesticides in India

This study visualizes emerging patterns in pesticide accumulation in 19,573 Indian farms based on Soil Health Card data (available from the Indian government’s public database) and high-resolution climate data. Modellign with BRTSim was conducted to predict the pesticide concentrations over time for a hypothetical scenario in which a constant pesticide application rate was maintained across all farms. 

Annual variations of predicted leaching from the topsoil to below root zone (100-200 cm) are shown for 46 pesticides used in India. Each dot represents a unique village: 3,861 dots cover 19,573 Indian farms in total.

During a 20-year simulation, the dot color gradually turns from yellow to blue (low to high). Pesticides that leach into below root zone tend to persist longer, posing potential risks to groundwater quality and overall soil health. The video shows that pesticide accumulation (specifically leaching to below root zone) varies across locations, and it differs from pesticide to pesticide.

This work identified regional hotspots of pesticide accumulation. Notably, potential hotspots are found in several areas with high biodiversity and unique agricultural practices such as organic farming regions. For example, Sikkim emerged as a hotspot with exceptionally high pesticide leaching ratios (Fig. 2, Area w). Since its designation as an “Organic State” in January 2016, pesticide application has ceased in Sikkim.  Further studies are recommended to assess residual leaching from past pesticide applications