Drought response of upland oak (Quercus L.) species in Appalachian hardwood forests of the southeastern USA

Table 5 Model fit statistics associated with BAI_resistance, BAI_recovery, and BAI_resilience during the second drought for northern red oak, black oak, chestnut oak, and white oak

	AIC_C	ΔAIC_C	w _i		AIC_C	ΔAIC_C	w _i		AIC_C	ΔAIC_C	w _i
Northern red oak	Drought 2—BAI _resistance				Drought 2—BAI _recovery				Drought 2—BAI _resilience
SI^b	−27.2	0.0	0.63	SI^a	−16.4	0.0	0.76	Null	26.0	0.0	0.44
Null	−24.7	2.5	0.18	DBH + RD + SI^a	−13.0	3.4	0.14	RD	27.2	1.2	0.24
DBH	−22.9	4.3	0.07	Null	−11.1	5.3	0.05	SI	28.1	2.1	0.15
RD	−22.6	4.6	0.06	RD	−10.4	6.3	0.03	DBH	28.2	2.2	0.15
DBH + RD + SI	−22.5	4.7	0.06	DBH	−9.0	7.4	0.02	DBH + RD + SI	31.6	5.6	0.03
Black oak
DBH^a	−10.3	0.0	0.80	Null	−10.2	0.0	0.48	DBH	−2.8	0.0	0.40
Null	−6.2	4.1	0.10	RD	−8.5	1.7	0.21	Null	−1.6	1.2	0.22
DBH^a + RD + SI	−4.6	5.7	0.05	SI	−8.0	2.2	0.16	DBH^a + RD + SI^a	−1.3	1.5	0.19
RD	−3.5	6.8	0.03	DBH	−7.6	2.6	0.13	RD	0.1	2.9	0.09
SI	−3.3	7.0	0.02	DBH + RD + SI	−3.7	6.5	0.02	SI	0.2	3.0	0.09
Chestnut oak
DBH	−12.5	0.0	0.45	Null	−15.7	0.0	0.49	Null	27.2	0.0	0.34
Null	−11.2	1.3	0.23	SI	−13.6	2.1	0.17	DBH	27.2	0.0	0.34
RD	−10.2	2.3	0.14	RD	−13.5	2.2	0.16	RD	28.5	1.3	0.18
SI	−9.3	3.2	0.09	DBH	−13.4	2.3	0.16	SI	29.5	2.3	0.11
DBH + RD + SI	−9.3	3.2	0.09	DBH + RD + SI	−8.8	6.9	0.02	DBH + RD + SI	31.3	4.1	0.04
White oak
Null	−26.8	0.0	0.42	Null	−22.4	0.0	0.48	Null	−10.6	0.0	0.35
DBH	−25.6	1.2	0.23	SI	−20.6	1.8	0.20	SI	−10.1	0.5	0.27
SI	−24.9	1.9	0.16	DBH	−20.2	2.2	0.16	DBH	−9.7	0.9	0.22
RD	−24.8	2.0	0.16	RD	−20.0	2.4	0.15	RD	−8.5	2.1	0.12
DBH + RD + SI	−21.0	5.8	0.02	DBH + RD + SI	−15.7	6.7	0.02	DBH + RD + SI	−6.2	4.4	0.04

DBH is tree-level diameter at breast height (cm), RD is plot-level relative density (%), and SI is plot-level site index (m). ΔAIC_C refers to the change in AIC_C compared to the best overall model (i.e., the model corresponding to the lowest AIC_C), and w _i is Akaike weight.
^aInformative (i.e., 95 % confidence interval that does not contain zero) and negative parameter estimate
^bInformative and positive parameter estimate

ISSN: 1297-966X