Table 1 Topological properties of the empirical species-species co-occurrence networks of bacterial and archaeal communities and their associated random network

No. of original OTUs

300

300

300

300

300

300

300

300

300

300

Network size (nodes)

212

293

295

293

289

277

296

295

294

295

Sequence number

272,449

67,334

70,351

66,687

70,444

855,275

218,993

225,426

216,593

224,045

Links

1083

1700

2959

1824

2477

3721

4904

4298

3224

3952

Degree

10.217

11.604

13.281

12.451

17.142

26.866

33.135

29.139

21.932

26.793

Average clustering coefficient

0.504

0.39

0.377

0.399

0.46

0.544

0.56

0.527

0.468

0.528

Diameter

9

8

9

9

8

7

8

6

7

7

Density

0.048

0.04

0.045

0.043

0.06

0.097

0.112

0.099

0.075

0.091

Average path length

3.499

3.258

3.22

3.357

3.024

2.674

2.654

2.748

2.867

2.827

Modularity

0.52

0.544

0.512

0.53

0.549

0.39

0.382

0.399

0.455

0.419

R² of powerlaw

0.87

0.383

0.607

0.44

0.459

0.659

0.338

0.439

0.352

0.519

Average clustering coefficient

0.048

(± 0.040)

0.040

(± 0.002)

0.068

(± 0.002)

0.042

(± 0.002)

0.060

(± 0.002)

0.097

(± 0.002)

0.112

(± 0.001)

0.099

(± 0.001)

0.075

(± 0.002)

0.091

(± 0.001)

Average path length

2.554

(± 0.005)

2.583

(± 0.003)

2.169

(± 0.002)

2.526

(± 0.002)

2.280

(± 0.002)

1.968

(± 0.002)

1.909

(± 0.001)

1.951

(± 0.001)

2.104

(± 0.002)

1.988

(± 0.002)

Modularity

0.245

(± 0.011)

0.228

(± 0.008)

0.161

(± 0.006)

0.218

(± 0.008)

0.178

(± 0.007)

0.130

(± 0.005)

0.112

(± 0.005)

0.123

(± 0.005)

0.151

(± 0.006)

0.131

(± 0.005)