Table 2.
Descriptive statistics (mean ± SD) of CO2 and NH3 concentrations at 4 different testing sampling locations (A, B, C, and D).
| Gases | Daily average ambient temperature range (°C) (days encountered this range) | Daily mean concentration (mean ± SD, ppm) |
TOUT × location interaction | |||
|---|---|---|---|---|---|---|
| Sampling point A | Sampling point B | Sampling point C | Sampling point D | |||
| CO2 | <0 (4 D) | 2,924 ± 416b,A | 3,352 ± 487a,A | 3,214 ± 421a,A | 3,046 ± 466b,A | 1 |
| 0 to 10 (8 D) | 1,896 ± 358c,B | 2,389 ± 395a,B | 2,239 ± 375b,B | 2,350 ± 448a,B | ||
| 10 to 20 (16 D) | 1,501 ± 357c,C | 1,786 ± 465a,C | 1,689 ± 410b,C | 1,789 ± 418a,C | ||
| >20 (20 D) | 707 ± 307c,D | 1,030 ± 284a,D | 917 ± 281b,D | 995 ± 363a,D | ||
| NH3 | <0 (4 D) | 7.8 ± 2.8d,A | 22.0 ± 5.2b,A | 20.4 ± 4.5c,A | 28.1 ± 4.7a,A | 1 |
| 0 to 10 (8 D) | 2.4 ± 2.2d,B | 14.6 ± 5.2a,B | 11.1 ± 4.1c,B | 12.8 ± 3.7b,B | ||
| 10 to 20 (16 D) | 1.4 ± 2.3c,B | 11.7 ± 6.0a,C | 9.5 ± 4.6b,C | 10.1 ± 5.1b,C | ||
| >20 (20 D) | 0.0 ± 0.0d,C | 2.0 ± 2.6a,D | 0.8 ± 1.9c,D | 1.2 ± 2.2b,D | ||
Results of the two-way ANOVA for effects of sampling location and TOUT categories and sampling location × TOUT on CO2 and NH3 concentrations are included.
Different superscript lowercase letters within the same row indicate that means under the same thermal category differ significantly (P < 0.05) using the Tukey test for difference of the means.
Different superscript uppercase letters within the same column indicate that means under the same sampling location differ significantly (P < 0.05) using the Tukey test for difference of the means.
There is a significant interaction effect of the outside temperature categories and the sampling locations (P < 0.001).