2.4. Statistical analysis
Statistical analysis was performed using SPSS 16.0 (SPSS for
Windows, Version 16.0, USA). Correlation analysis was used to test
the linear correlation coefficients of the chemical, odor, and theoretical
odor concentrations. r2 was obtained using values calculated
at the 95% and 99% confidence levels by the regression model.
3. Results and discussion
3.1. Odor concentration on the working face and its temporal variation
The results of olfactometric analysis and meteorological data
during the sampling are given in Table 3. Odor concentration on
the working face of the landfill fluctuated significantly in different
sampling periods (Fig. 1). Serious odor pollution occurred in spring
(2012) and autumn (2012 and 2013), while overall low odor concentrations
were found in summer and winter (2012 and 2013).
Odor pollution on the working face is caused by odorous compounds
(OCs) that exceed their threshold concentrations.
Correlations between odor concentration and total OCs concentration
were found with r2 = 0.41 (n = 42, P < 0.01), which indicated
that 41% of the variance in odor concentrations can be explained
by the total OCs concentrations. The result is highly consistent
with the results of Dincer et al. (2006), who also showed a correlation
between odor concentration and total concentration of volatile
organic compounds on the working face of a landfill with r2 = 0.41