Table 4. Pearson’s correlation coefficients of PM_2.5 and its components.

	PM2.5	Sulfate	Nitrate	Chloride	Ammonium	Sodium	Potassium	Magnesium	Calcium	Elemental carbon	Organic carbon
PM2.5	1
Sulfate	0.73	1
Nitrate	0.61	0.17	1
Chloride	0.45	−0.06	0.57	1
Ammonium	0.89	0.87	0.57	0.27	1
Sodium	0.26	0.18	0.15	0.20	0.22	1
Potassium	0.74	0.57	0.44	0.36	0.68	0.37	1
Magnesium	0.34	0.44	0.07	−0.04	0.37	0.62	0.48	1
Calcium	0.32	0.24	0.16	0.06	0.25	0.28	0.44	0.49	1
Elemental carbon	0.73	0.30	0.52	0.56	0.49	0.10	0.43	0.02	0.08	1
Organic carbon	0.78	0.39	0.43	0.45	0.54	0.19	0.59	0.17	0.19	0.75	1

PM_2.5, fine particulate matter.