Table 4.

Coefficient of determination and Akaike (AIC) value between the variations in above-ground dry matter productivity in response to changes in N supply and cutting frequency and trait values or trait plasticity (Δtraits)

	Trait combination	r2	AIC
(A) With trait values on average of C−N+ treatment
N supply	SL, LL, LDMC, SLA, TD, BF	0·43	−20·52
Cutting frequency	VE, LL, SLA, CC, ME	0·64	−51·43
N supply and cutting frequency	NM, TD, ME	0·27	−27·87
(B) With traits plasticity (Δtraits)
N supply	ΔSL, ΔLDMC, ΔTD	0·60	−37·51
Cutting frequency	ΔNM, ΔLL, ΔLDMC, ΔEG	0·44	−37·72
N supply and cutting frequency	ΔNM, ΔSL, ΔTD, ΔLNCF	0·55	−43·17
(C) With all variables (traits values on average of C−N+ treatment and traits plasticity)
N supply	SL, LL, SLA, CC, ΔNM, ΔSL, ΔCC, ΔTD	0·89	−64·85
Cutting frequency	NM, CC, ADF, ME, ΔADF	0·66	−53·63
N supply and cutting frequency	SL, SLA, CC, ME, ΔNM, ΔSL, ΔTD	0·68	−46·17
(D) With only the significant variables in the two previous simple regression analyses (see Table 3)
N supply	ΔLDMC, ΔTD, BF	0·58	− 43·53
Cutting frequency	NM, CC, ADF, ME, ΔADF	0·66	− 53·63
N supply and cutting frequency	VE, ME, ΔNM, ΔSL, ΔTD	0·60	− 46·33

The models selected are shown in bold (with the lowest AIC value and with the lowest number of traits). See Materials and methods for calculation of variation in ANPP and trait plasticity.

For trait abbreviations, see Table 1.