Biomass burning contributions to urban PM_2.5 along the coastal lines of southeastern China

Figures & data

Fig. 1.  Administrative division of Fujian province and location of the four sampling sites (solid point in Xiamen, Quanzhou, Putian and Fuzhou).

Fig. 2 Temporal variations of LG concentration and rainfall measured at (a) XM, (b) QZ, (c) PT and (d) FZ sites during the eight sampling periods. The two orange dashed bars represent high biomass burning activities around the traditional Ching-Ming festival.

Fig. 3 Variations of LG and K⁺ average concentrations and MODIS fire counts in Fujian province.

Fig. 4 Correlations between LG and nss-K⁺ for all samples at each site.

Fig. 5 (a) Seasonal variations of WSOC concentration, and ratios of (b) LG/nss-K⁺, (c) WSOC/OC, (d) SOC/OC, (e) LG/OC, (f) LG/WSOC, (g) OC_BB/OC and (h) WSOC_BB/WSOC in PM_2.5 at the four urban sites.

Table 1. Correlation coefficient between species (n=60)

Sampling period	LG vs Abs365	LG vs OC	LG vs WSOC	LG vs EC	LG vs nss-K^+	WSOC vs Abs	WSOC vs OC	WSOC vs nss-	WSOC vs	WSOC vs SOC
2011.11	0.432**	0.564**	0.432**	0.529**	0.420*	0.889**	0.792**	0.757**	0.573**	0.670**
2012.1	0.283*	0.322**	0.307**	0.491**	0.254*	0.693**	0.650**	0.676**	0.604**	0.595**
2012.4	0.482**	0.475**	0.380**	0.227*	0.358**	0.690**	0.713**	0.548**	0.488**	0.552**
2012.7	0.418**	0.635**	0.253*	0.486**	0.358**	0.829**	0.886**	0.478**	0.401**	0.605**
2012.11	0.403**	0.348**	0.276*	0.266*	0.353**	0.838**	0.715**	0.726**	0.422**	0.697**
2013.1	0.485**	0.750**	0.596**	0.677**	0.384**	0.700**	0.663**	0.682**	0.527**	0.686**
2013.4	0.477**	0.389**	0.269**	0.435**	0.570**	0.706**	0.659**	0.584**	0.634**	0.620**
2013.6/7	0.312*	0.444**	0.453**	0.598**	0.575**	0.763**	0.746**	0.485**	0.346**	0.682**

**Correlation is significant at the 0.01 level (one-tailed). *Correlation is significant at the 0.05 level (one-tailed).

Fig. 6 (a) Mass contributions and (b) relative mass contributions of biomass burning on PM_2.5 between LG-predicted and PMF-predicted analysis.

Fig. 7 Pie-charts showing the source apportionment of PM_2.5 at (a) XM, (b) QZ, (c) PT and (d) FZ. The sources include biomass burning (F1), fuel oil (F2), vehicular emission (F3), secondary nitrate and sulphate aerosol (F4), crustal dust (F5), metallurgical emission at XM and QZ or mixed source of metallurgical emission and secondary sulphate aerosol at PT and FZ (F6), secondary sulphate and organic aerosol at XM and QZ or waste incineration emission at PT and FZ (F7).