Summary of optimal models for vegetation responses in relation to N deposition and climate variables.

(+/−)  =  direction of response; x  =  interaction; P values  =  * <0.05, **<0.001, ***<0.001; gdd  =  growing degree days; ht  =  Calluna canopy height.

(±) 代表反应方向；x 代表交互作用；P值标注标准如下：* 表示P<0.05，**表示P<0.001，***表示P<0.001；gdd 为生长度日（growing degree days）；ht 为帚石楠（Calluna）冠层高度。