Fig. S1

1. a b Highways 0 20 40 Other roads Urban area Kilometers Fig. S1

2. 0 0 0 0 0 0 0 0 20 20 20 20 20 20 20 20 40 40 40 40 40 40 40 40 Kilometers Kilometers Kilometers Kilometers Kilometers Kilometers Kilometers Kilometers a c b 9.0 103 3.5 104 2.7 105 7.0 103 2.5 104 1.3 105 5.0 103 0 20 40 1.5 104 7.5 104 3.0 103 0.5 104 1.0 103 2.5 104 Kilometers d e f 9.0 103 2.7 104 7.0 103 7.0 103 1.7 104 5.0 103 5.0 103 1.2 104 3.0 103 3.0 103 7.5 103 1.0 103 1.0 103 2.5 103 g h i 2.2 103 1.7 103 9.0 104 5.0 104 1.2 103 5.0 104 3.0 104 7.5 102 1.0 104 1.0 104 2.5 102

3. 105 104 Crenrachaeal 16S gene copy ng-1 DNA 103 102 10 102 103 104 105 Crenarchaeal amoA gene copy number ng-1 DNA Fig S3

4. 0 0 0 0 0 0 0 20 20 20 20 20 20 20 40 40 40 40 40 40 40 Kilometers Kilometers Kilometers Kilometers Kilometers Kilometers Kilometers a b c 0.11 0.045 0.07 0.35 0.035 0.05 0.025 0.25 0 20 40 0.03 0.015 0.15 Kilometers 0.01 0.05 0.005 d e f 0.009 0.27 0.0175 0.007 0.17 0.0125 0.005 0.12 0.0075 0.003 0.075 0.025 0.001 0.0025 g h Fig. S4 2.75 450 2.25 350 1.75 250 1.25 150 0.75 50 0.25

5. a c b 0.285 0.0048 0.0058 0 20 40 0 20 40 0 20 40 0.059 0.0009 0.0017 Kilometers Kilometers Kilometers Fig. S5