Table 4. Comparison of Barrow soil metagenomes presented in this study (all layers combined) with published Waseca farm soil metagenome [6].

	Waseca (%)	Barrow (%)	Pearsona χ2	Pa
Functional genes
Anaerobic reductases	0.248	0.266	1.299	0.2545
Terminal cytochrome C oxidases	0.168	0.080	82.819	0.0001
Terminal cytochrome d ubiquinol oxidases	0.023	0.047	14.289	0.0002
Methanogenesis	0.035	0.164	131.527	0.0001
Acetogenesis	0.080	0.080	0	1
Fermentation	1.239	1.115	14.346	0.0002
Decaheme cytochromes	0.009	0.018	5.897	0.0152
Denitrification	0.095	0.029	103.052	0.0001
Sulfate reduction	0.009	0.020	6.535	0.0106
TMAO reduction	0.012	0.009	0.892	0.3449
DMSO reduction	0.016	0.011	2.905	0.0883
As reduction	0.025	0.019	2.277	0.1313
Dehalorespiration	0.000	0.002	2.8	0.0943
Oxidative stress	0.770	0.564	73.088	0.0001
Catalase	0.041	0.049	1.28	0.258
SOD	0.020	0.023	0.173	0.6775
Peroxidase	0.020	0.018	0.467	0.4943
Aerotolerance (Bacteroides)	0.048	0.039	1.85	0.1738
Genomes
Methanogens	0.765	1.377	322.21	0.0001
Fe reducing bacteria	4.070	3.954	3.578	0.0586
Dehalorespirers	2.232	1.214	758.443	0.0001
Sulfate reducing bacteria	0.860	1.316	182.283	0.0001
Syntrophic bacteria	0.502	1.168	464.345	0.0001
Strict Fermenters (Clostridiales and Bacteroides)	2.350	2.484	7.848	0.0051

^aPearson chi-squared statistic (χ², and corresponding P value) compares proportions of sequences between the two soils.