Variables related to nitrogen deposition improve defoliation models for European forests

Table 2 Spearman rank order correlation coefficient between N deposition and the other variables considered in the study

Variable	All plots	Beech	Norway spruce	Scots pine
Latitude	−0.34	0.58	−0.38	−0.71
Longitude	−0.34	0.23	−0.36	−0.70
Altitude	0.16	−0.38	0.28	0.02
Tree density	−0.25	−0.05	−0.28	−0.16
Pr	0.33	−0.23	0.53	0.18
Summer Pr	−0.18	0.00	−0.28	0.14
BADoAP	0.01	0.06	−0.04	−0.07
Foliar N/P	0.43	−0.14	0.48	0.74
Foliar N/Ca	0.18	0.55	0.62	−0.14
Foliar N/Mg	0.44	0.21	0.40	0.59
Foliar N/K	0.67	0.60	0.73	0.49
Soil pH	−0.46	−0.40	−0.51	−0.76
Soil C/N	−0.12	0.34	0.18	−0.33
Soil BCE	0.27	−0.24	0.07	0.63

ISSN: 1297-966X