Table 15 Statistical analysis for fluctuated concentration rate of shrub structure type

a. Group statistics(winter)
Classification	Number of samples (N)		Mean value (%)		Std. deviation (%)		Std. error (%)		Min (%)		Max (%)
Single layer	32		88.788		19.4664		3.4412		49.2		116.7
Double layer	192		81.160		19.4769		1.4056		44.3		132.0
Multi layer	32		68.925		24.5723		4.3438		35.6		116.7
Total/mean	256		80.584		20.7211		1.2951		35.6		132.0
b. Levene's test for equality of variances (winter)
Levene's statistics		df1				df2		Sig.
2.258		2				253		0.107
c. Analysis of variance (ANOVA) (winter)
Classification		Sum of squares		df		Mean squares		F		Sig.
Between groups		6,567.143		2		3,283.572		8.072		0.000
Within groups		102,920.434		253		406.800
Total		109,487.578		255