Table 1.

Shifts in whether a positive net biodiversity effect is explained by (A) complementarity effects at a local scale, but selection effects at a larger scale $\left(NB{E}_{\gamma }={\displaystyle {\sum }_k^{P}C{E}_{\alpha }=S{E}_{\gamma }}\right)$ or (B) selection effects at a local scale, but complementarity effects at a larger scale $\left(NB{E}_{\gamma }={\displaystyle {\sum }_k^{P}S{E}_{\alpha }=C{E}_{\gamma }}\right).$ Example levels of ecosystem functioning (arbitrary units) in monoculture (M_ik) and mixture (Y_ik) for species i at place k. Biodiversity effects are quantified by Equations E1 and E2 in Box 2, assuming equal initial proportions RY_E,ik = 0.5 for all i and k. For simplicity, only one time is considered. Values shown in B are approximate.

		A		B
Place (k)	Species (i)	Mik	Yik	Mik	Yik
1	1	200	200	50	8.15
1	2	200	200	350	291.7
2	1	100	0	0.44	0.88
2	2	100	0	1	0
Net Biodiversity Effect: $NB{E}_{\gamma }={\displaystyle {\sum }_k^{P}NB{E}_{\alpha }}$		100		100
Local complementarity effects: ${\displaystyle {\sum }_k^{P}C{E}_{\alpha }}$		100		0
Local selection effects: ${\displaystyle {\sum }_k^{P}S{E}_{\alpha }}$		0		100
Total complementarity effects: CEγ		0		100
Total selection effects: SEγ		100		0