Table 2.

Models predicting total N concentration in NLA 2007 Lakes. All variables are significant (p<0.001).

Models and variables	R2adj	F-statistic	AIC	t value
log(Fertilizer Input)	0.18	200	−48.0	14.2
log(Total N Input)	0.22	249	−87.2	15.8
log(Depth)	0.35	486	−249.9	−22.1
E:I	0.31	406	−201.9	20.1
log(Fert)+Chironomid δ15N	0.21	115	−70.3
log(Fert)				11.4
Chironomid δ15N				5.0
log(Total N)* Chironomid δ15N	0.25	97	−107.8
log(Total N)				9.8
Chironomid δ15N				4.5
interaction				−3.1
log(Depth) + Chironomid δ15N	0.43	330	−353.6
log(Depth)				−22.8
Chironomid δ15N				10.6
E:I+ Chironomid δ15N	0.40	291	−313.8
E:I				21.2
Chironomid δ15N				11.0
E:I+ Chironomid δ15N+ log(Total N)	0.49	280	−456.7
E:I				20.7
Chironomid δ15N				6.6
log(Total N)				12.5
E:I+ Chironomid δ 15 N+ log(Total N)+ log(Depth)	0.61	337	−675.6
E:I				15.5
Chironomid δ15N				7.4
log(Total N)				11.5
log(Depth)				−16.0