Environmental impact of water resource use in the Fucino Plain (Central Italy) – second aspect: contamination from pesticides and fertilisers

The previous paper has already outlined the environmental features of this wide intermontane basin, as well as the first issue, i.e. possible water deficit. This paper deals with water contamination due to the use of pesticides and fertilisers.Surveys conducted in the last decade have shown that, in Winter and Spring, the local water (especially surface water) is particularly rich of nitrates. Nitrates are above 50 mg/L in the central and western sectors of the plain, but fall to 5-10 mg/L in its southern sector. However, these are not absolute values because, in Summer, nitrate concentrations tend to decrease owing to less use of pesticides. In some zones, concentrations depend more on municipal waste water or sewage water releases than on farming practices. Ammonium ion concentrations are not significantly variable on a seasonal basis: 1 mg/L on average, with peaks of some mg/L. The content of nitrites is always below 1 mg/L and significant only during the Winter sampling surveys: 0.44 mg/L on average vs. 0.21 mg/L in the other surveys.Pesticide analyses suggest that the content of the active principle Linuron, albeit with seasonal variations, is high (0.1 to 2.8 _g/L), while Dicloran and Carbaryl are lower (below 1 _g/L and below 1 _g/L, respectively). These findings infer that the dissemination of pesticides in the investigated water (especially in surface water) is extremely limited and concentrated in welldefined zones and periods The variability of the collected data depends, among others, on rainfall. Poor precipitation may induce particularly dry periods, during which the dilution of contaminants is lessened by the low flow of surface and spring water.

کلیدواژه ها:

Groundwater management ، Central Italy ، irrigation ، nitrates ، pollution risk