Spatial analysis of grey water in Italian cereal crops production

•A series of test showed the presence of spatial dependence for the four cereal crops indicated.•The output reveals also significant presence of spatial heterogeneity.•Policy makers should include spatial considerations in the field of water pollution management. Explorative spatial data analysis (ESDA) is a set of tools to emphasise spatial structure in case of localised data and widely used for testing effects in the case of environmental data. Grey water indicator is considered as a reliable water pollution indicator able to show the quality of water, useful in agriculture and crops production. In this paper, an analysis on the presence of spatial effects in the grey water indicator for crops production is proposed. This analysis is carried out on four cereal crops (i.e., corn, barley, durum wheat and soft wheat) in Italian regions for the period 2011–2015. The output reveals the presence of spatial effects especially for corn which shows a high level of polarisation between South and North regions. ESDA analysis indicates that grey water descending from cereal crops production is characterised by a persistent presence of positive spatial dependence and spatial heterogeneity. Policy makers should take into account those effects to improve the bundle of policies in the field of water management.