Decoupling pollution-agricultural growth and predicting climate change impacts on decoupling index using Bayesian network in different climatic regions

Applying the principles of healthy products through agriculture practices has become an important issue due to significant environmental impacts of agrochemicals application. The agrochemicals have been recognized as an essential component of modern agriculture, but they are also an important source of environmental pollution that threatens the human’s health and are main sources of carbon emissions. Pesticides and fertilizers application are important in the process of Iran’s food production. In Iran, intensifying the agricultural production has led to overuse of chemical fertilizers and pesticides. This work is the first effort to quantify and compare the decoupling index pollution from agricultural sector using Tapio decoupling indicator and predict climate change impacts on this index by using Bayesian network across the whole country of Iran. For this purpose, required annual data of predictor variables for the period of 2008 to 2018 was used to calculate the decoupling index. For projecting climate change impacts on this index by using Bayesian network, monthly mean values of climatic variables were used. While Iranian farmers are criticized for pesticide overuse, these study findings showed that during the period of 2008–2018, decoupling index for pesticides (agricultural pollution by using pesticide) and decoupling index for fertilizer (agricultural pollution by using fertilizer) in the selected provinces fluctuate between RD-SD, SD-SD, SD-SD, and RD-SD. Therefore, the decoupling states show that in most study years, there is a strong decoupling of agricultural growth in selected provinces. This means that in the selected provinces, pollutant emissions of chemical fertilizer and pesticides use for agricultural productions have decreased and it has been well controlled. Therefore, by expansion of agricultural sector, the situation of agricultural pollution in these provinces in most years has not been intensified. Control of agricultural pollution in these provinces has shown a positive and significant impact on public health. In selected provinces, the cleaner agricultural products and application of organic fertilizers have been increased. This study results also showed that the climate change will accelerate increment of pests population and thus pesticides application in different climatic regions.