Table 1. Characteristics of sequence-based prokaryotic community data sets for analysis in this study.

Case	Targeted community	Study location	Scale	Sequencing approach	16S region (primers)	Read length	Subsampled read	Data point	Reference
1	Soil prokaryotes (surface)	North and South America	Global	Amplicon-454	V1–V2 (27F/338R)	312	400	88	Lauber et al. (2009)
2	Soil prokaryotes (surface)	Canadian, Alaskan, and European Arctic	Global	Amplicon-454	V1–V2 (27F/338R)	312	400	40	Chu et al. (2010)
3	Soil prokaryotes (surface)	New York City's Central Park, USA	Local	Amplicon-Illumina	V4–V5 (515F/806R)	292	37 000	580	Ramirez et al. (2014)
4	Soil prokaryotes (surface)	Long Island's vineyards, New York, USA	Local	Amplicon-Illumina	V4–V5 (515F/806R)	292	1500	94	Zarraonaindia et al. (2015)
5	Seawater prokaryotes (surface)	Tara Oceans (Atlantic, Pacific, Indian Oceans...)	Global	Metagenome-Illumina	Varied (shotgun)	164	35 000	59	Sunagawa et al. (2015)
6	Seawater prokaryotes (Chl maximum)	Tara Oceans (Atlantic, Pacific, Indian Oceans...)	Global	Metagenome-Illumina	Varied (shotgun)	164	35 000	39	Sunagawa et al. (2015)
7	Seawater prokaryotes (surface)	Station L4 of the Western English Channel	Local	Amplicon-454	V6 (967F/1064R)	98	4200	61	Gilbert et al. (2012)
8	Seawater prokaryotes (surface)	A short transect of the Southern East China Sea	Local	Amplicon-454	V6 (967F/1064R)	98	9800	27	Yeh et al. (2015)