Results
Water used for irrigation
Deviance analysis resulting from the generalized linear
model approach showed no significant differences
between years, between seasons, nor between seasons
within each year in terms of AST presence. However, there
were significant differences between seasons when the
presence of both EV and RV were considered. The presence
of these pathogens was significantly more frequent
during the cold-dry season (0.75 and 0.35, respectively)
than in the warm-rainy season (0.10 and 0.05, respectively)
(Figure 1).
The presence of AST and RV showed no significant relationship
with either the environmental variables recorded
(pH, temperature, conductivity and dissolved oxygen concentration)
or with the abundance of bacterial indicators.
By contrast, EV presence was significantly related to temperature
(Figure 2) but not to the abundance of any of the
bacterial indicators.
As for bacterial indicators, all samples were positive for
the three bacterial groups, indicating continuous faecal
contamination of the water used for irrigation. Deviance