TABLE 1.

Summary table of pairwise cooccurrence analyses for each environment and dilution

Dilution	No. of samples	No. of species	Total no. of species pair combinations	No. of analyzed combinationsa	No. of positive interactionsb	No. of negative interactionsb	Median powerc	FDR (%)d
NO3-10−1	94	230	26,335	802	58	47	6.2	1.53
NO3-10−2	96	124	7,626	317	12	9	7.5	3.02
NO3-10−3	54	91	4,095	37	1	0	8.2	7.40
NO3-10−4	0	0	NAe	NA	NA	NA	NA	NA
NO3-10−5	1	1	NA	NA	NA	NA	NA	NA
O2-10−1	96	164	13,366	1,303	8	8	9.75	16.29
O2-10−2	96	109	5,886	564	15	3	9.85	6.27
O2-10−3	79	65	2,080	74	2	0	7.7	7.40
O2-10−4	22	37	666	12	0	0	NA	NA
O2-10−5	3	6	NA	NA	NA	NA	NA	NA

^aAnalyzed combinations represent only those species pairs expected to have 1 or more cooccurrences.

^bSignificance at the threshold of a P value of <0.001.

^cCalculated as |observed interactions − expected interactions|.

^dFDR, false-discovery rate.

^eNA, not applicable.