Effect of Ammonia andPlants on Orthoptera species.

All variables analysed at the level of 10 km grid cells. Response variables (Plant richness change and Orthoptera richness change) were log transformed to normalize residuals: Orthoptera = log(orthoptera richness in post period/orthoptera richness in pre period); Plants = log (plant richness in post period/plant richness in pre period); Explanatory variables were: NHx (Ammonia deposition), Plants, Interaction NHx*Plants.The two most parsimonious models are listed according to AICc values and the equation of the best model (lowest AICc) is provided for each subset. P-values were obtained from a likelihood ratio test in which deviances with and without that term in the model were compared. n.s., P>0.05. Orthoptera species richness models and Nitrogen deposition models were corrected for spatial autocorrelation of residuals (exponential and spherical correlation structure, respectively). The residuals of plants species richness change models were not significantly spatially correlated. The symbol ‘–’ represents a variable not included in the model. n/a = not applicable.