Comparative agroenvironmental risks of pesticides in different cropping systems: application of the I-Phy indicator

The green revolution laid the foundations of modern agriculture, by using science and technology to produce more from same resources. The pesticides contributed to agricultural output in the last decades; however, their use has resulted in environmental pollution, health problems, soil and water contamination and negative impact on biota. The impacts of agricultural activities to the environment depended on the practices adopted during the production process. Measurement tools to assess the impacts of those practices are necessary to improve agricultural systems and must be evaluated in different ecosystems. Different soils, climates and crops impose many phytosanitary arrangements. This complex network and the fact that most of the indicators and measurement tools are developed for temperate climates makes it difficult to quantify the environmental impacts under subtropical regions. The I-Phy index is a predictive indicator that assesses the risks of pesticide usage in agriculture and identifies as to which practices generate the main environmental impacts of pesticides. The objective of this study was to test the suitability of the I-Phy index for subtropical conditions and, if suitable, compare the pesticide risk between two regions. Five crops were assessed under three different cropping systems: no-tillage, minimal tillage and conventional tillage. The I-Phy index was sensitive in both regions and capable of identifying that no-tillage generally presented risks of environmental pollution slightly lower than the other tillage systems. The results of I-Phy index showed that high environmental vulnerability of the fields and the numerous applications of active ingredients with high risks resulted in high risks of general contamination. The application of I-Phy on these two case studies showed the indicator can be useful as a support tool to farmers, research and extension institutions pursuing management practices with lower impact on the environment.