Ecological Archives A025-135-A1

Ecological Archives A025-135-A1

Aditya Singh, Shawn P. Serbin, Brenden E. McNeil, Clayton C. Kingdon, and Philip A. Townsend. 2015. Imaging spectroscopy algorithms for mapping canopy foliar chemical and morphological traits and their uncertainties. Ecological Applications 25:2180–2197. http://dx.doi.org/10.1890/14-2098.1

Appendix A. Comparisons of model accuracies with literature, species-wise estimates of canopy foliar traits,comparisons of models built with different canopy weighing schemes, comparisons of spatial predictions of foliar traits.

Table A1. Review of recent literature on the application of imaging spectroscopy to map foliar chemistry. Note that in order to conform to the analytical methods presented in this study, we do not include studies that employ inversion of radiative transfer models to map canopy chemical properties.

Trait	Vegetation type	Location	Sensor	Plots	Images	Method	R2Cal	RMSECal	R2Val	RMSEVal	Source
C	Mixed needleleaf-broadleaf	Switzerland	HyMap	28	4	B&B	0.31	1.21 (RMSE)			Huber et al. (2008)

Lig	Oak, Pine	Wisconsin	AIS	20	1	MLR	0.85	1.9 (SE)			Wessman et al. (1989)
Lig	Juniper - Coastal rainforest	West-central Oregon	AVIRIS	17	4	MLR	0.93	277.80 (SEC)			Johnson et al. (1994)
Lig	N Hardwood and needleleaf	Harvard Forest, MA	AVIRIS	21	1	MLR	0.70	2.38 (SECV)	0.27	3.87 (SEP)	Martin and Aber (1997)
Lig	N Hardwood and needleleaf	Blackhawk Island, WI	AVIRIS	20	1	MLR	0.90	0.85 (SECV)	0.01	4.33 (SEP)	Martin and Aber (1997)
Lig:N	N Hardwood and needleleaf	White Mountain NF, NH	AVIRIS	81	56	PLSR	0.69	0.23 (SEC)		0.23 (SECV)	Ollinger et al. (2002)
Lignin	Juniper - Coastal rainforest	West-central Oregon	AVIRIS	9	1	MLR	0.75	17.90 (SEE)			Matson et al. (1994)
Lignin	Slash Pine	Gainesville, FL	AVIRIS	14	4	MLR	0.98				Curran et al. (1997)
Lignin	Chaparral	Santa Monica, CA	AVIRIS	23	1	MLR	0.81	5.39 (RMSE)			Serrano et al. (2002)

N	N Hardwood and needleleaf	Wisconsin	AIS	20	1	MLR	0.83	0.04 (SE)			Wessman et al. (1989)
N	Juniper - Coastal rainforest	West-central Oregon	AVIRIS	9	1	MLR	0.72	2.40 (SEE)			Matson et al. (1994)
N	Juniper - Coastal rainforest	West-central Oregon	AVIRIS	25	4	MLR	0.90	0.70 (SEC)			Johnson et al.(1994)
N	Slash Pine	Gainesville, FL	AVIRIS	14	4	MLR	0.98				Curran et al. (1997)
N	N Hardwood and needleleaf	Harvard Forest, MA	AVIRIS	21	1	MLR	0.87	0.23 (SECV)	0.83	0.27 (SEP)	Martin and Aber (1997)
N	N Hardwood and needleleaf	Blackhawk Island, WI	AVIRIS	20	1	MLR	0.85	0.15 (SECV)	0.75	1.32 (SEP)	Martin and Aber (1997)
N	Chaparral	Santa Monica, CA	AVIRIS	23	1	MLR	0.75	0.55 (RMSE)			Serrano et al. (2002)
N	N Hardwood and needleleaf	White Mountain NF, NH	AVIRIS	53	36	PLSR	0.82			0.23 (SECV)	Smith et al. (2002)
N	Eucalyptus spp.	Tumbarumba, Australia	Hyperion	14	1	PLSR	0.95	0.11 (SEC)	0.68	0.27 (SECV)	Coops et al. (2003)
N	Eucalyptus spp.	Tumbarumba, Australia	Hyperion	14	1	MLR	0.83	0.10 (SEC)			Coops et al. (2003)
N	N Hardwood and needleleaf	Bartlett Exp. Forest, NH	AVIRIS	49	1	PLSR	0.83	0.17 (SEC)	0.79	0.19 (RMSEP)	Smith et al. (2003)
N	N Hardwood and needleleaf	Bartlett Exp. Forest, NH	Hyperion	49	1	PLSR	0.82	0.17 (SEC)	0.60	0.25 (RMSEP)	Smith et al. (2003)
N	Deciduous Oak	Green Ridge SF, MD	Hyperion	20	1	PLSR	0.97				Townsend et al. (2003)
N	Deciduous Oak	Green Ridge SF, MD	AVIRIS	17	1	PLSR	0.84				Townsend et al. (2003)
N	N Hardwood and needleleaf	Bartlett Exp. Forest, NH	AVIRIS	56	1	PLSR	0.83	0.17(SEC)	0.70	0.19(RMSEP)	Ollinger and Smith (2005)
N	N Hardwood and needleleaf	Bartlett Exp. Forest, NH	Hyperion	56	1	PLSR	0.82	0.17(SEC)	0.25	0.25(RMSEP)	Ollinger and Smith (2005)
N	N Hardwood and boreal	Adirondacks, NY	Hyperion	28	2	PLSR	0.93	0.28(%)			McNeil et al. (2008)
N	Mixed needleleaf-broadleaf	Switzerland	HyMap	28	4	B&B	0.53	0.38 (RMSE)			Huber et al. (2008)
N	Various	USA, Costa Rica, Australia	AVIRIS	42-75	5	PLSR	0.83	0.14 (SEC)		0.19 (SECV)	Martin et al. (2008)
N	Various	USA, Costa Rica, Australia	Hyperion	42-75	6	PLSR	0.82	0.22 (SEC)		0.25 (SECV)	Martin et al. (2008)
N	Picea abies	Gerolstein, Germany	HyMap	13	1	MLR	0.57	0.05 (RMSE)			Schlerf et al. (2010)
N	Needleleaf	Vancouver Island, Canada	AVIRIS	17	1	PLSR	0.77	0.21 (SECV)			Hilker et al. (2012)
N	Needleleaf, Eucalyptus spp.	Tumut, NSW, Australia	HyMap	80	5	PLSR	0.54	0.90 (SEC)		0.11 (SECV)	Youngentob et al. (2012)
N	Needleleaf, Eucalyptus spp.	Tumut, NSW, Australia	HyMap	80	5	MLR	0.60	0.10 (SEC)		0.10 (SECV)	Youngentob et al. (2012)
N	Needleleaf, Eucalyptus spp.	Tumut, NSW, Australia	HyMap	80	5	MLR	0.58	0.10 (SEC)		0.10 (SECV)	Youngentob et al. (2012)
N	Sagebrush	Eastern Idaho	HyMap	35	1	PLSR	0.95		0.56	0.25 (PRESS)	Mitchell et al. (2012)

Table A2. Estimates of foliar traits measured in this study stratified by dominant canopy species. Species sorted by leaf habit (needleleaf, deciduous), and by relative frequency (%) in the overall dataset. Estimates of mean traits are presented along with standard deviations.

			N%		Marea		C%		ADF%		ADL%		Cellulose%		δ15N‰
Sp. Code	Species	Rel. Freq (%)	Mean	S.D.	Mean	S.D.	Mean	S.D.	Mean	S.D.	Mean	S.D.	Mean	S.D.	Mean	S.D.
Needleleaf
PIST	Pinus stroba	13.41	1.70	0.220	156.12	33.128	50.84	0.600	43.31	3.943	26.17	2.941	17.12	1.525	-1.11	1.172
PIRE	Pinus resinosa	7.66	1.43	0.211	190.70	15.563	50.87	0.581	46.50	2.129	26.68	1.316	18.81	1.343	-1.59	0.859
TSCA	Tsuga canadensis	4.21	1.75	0.272	116.14	16.517	49.95	0.308	30.23	4.271	15.95	2.572	13.79	1.910	-4.97	0.832
PIBA	Pinus banksiana	4.21	1.61	0.241	177.29	12.403	50.76	0.510	50.33	2.469	28.92	1.423	21.02	1.072	-4.48	0.350
ABBA	Abies balsamifera	2.68	1.64	0.148	149.74	23.107	51.79	1.113	40.02	3.409	23.42	2.140	14.87	1.568	-3.65	1.396
PIRU	Pinus rubens	1.92	1.40	0.262	150.87	6.423	50.71	0.742	44.28	5.162	24.68	1.637	17.80	4.043	-6.05	1.184
THOC	Thuja occidentalis	1.92	1.44	0.364	168.69	20.953	49.86	0.610	39.56	2.622	24.48	2.587	15.47	1.181	-3.91	1.277
PIMA	Pinus mariana	1.15	1.02	0.047	201.82	22.306	50.68	0.169	46.88	4.283	25.18	2.393	21.28	1.332	-6.03	0.215
JUVI	Juniperous virginiana	0.77	2.16	0.029	205.90	5.781	48.73	0.042	40.51	0.618	26.86	0.480	17.01	0.151	-1.91	0.146
LALA	Larix larcinia	0.77	1.50	0.103	168.59	7.197	50.16	0.031	50.17	0.650	30.58	0.075	19.50	0.713	-6.01	0.289
PISY	Pinus sylvatica	0.77	2.14	0.108	161.53	5.096	50.42	0.162	42.62	0.685	23.81	0.620	18.42	0.022	-1.86	0.056
PIAB	Picea abies	0.38	2.48	-	134.14	-	49.48	-	35.53	-	21.51	-	14.98	-	-3.00	-
PIVI	Pnius virginiana	0.38	1.71	-	136.64	-	50.54	-	39.34	-	22.06	-	18.31	-	-3.43	-
Broadleaf
ACSM	Acer saccharum	17.62	2.48	0.321	77.60	12.999	49.03	0.840	32.10	5.034	17.58	3.457	14.70	2.079	-3.72	1.141
QUAL	Quercus alba	6.90	2.86	0.212	92.66	10.772	49.44	0.478	33.40	1.951	19.29	1.319	15.33	0.521	-3.48	0.469
QURU	Quercus rubrum	6.51	2.75	0.184	97.14	9.028	49.78	0.835	36.47	3.005	22.51	2.541	15.70	1.393	-3.16	0.782
FAGR	Fagus grandifolia	4.21	2.20	0.332	82.02	12.634	50.21	0.567	43.01	2.940	24.93	1.973	17.91	1.929	-5.79	0.743
ACRU	Acer rubrum	3.45	2.28	0.264	82.25	12.101	49.81	0.877	34.84	5.373	19.72	3.178	15.40	2.698	-4.39	1.202
POTR	Populus tremuloides	3.07	2.56	0.243	79.84	13.786	50.35	0.804	35.60	3.292	25.51	3.653	17.62	1.491	-2.45	0.534
ACSN	Acer saccharinium	2.68	2.52	0.110	85.61	4.615	49.68	0.648	24.71	4.436	15.07	2.182	10.83	2.063	-2.17	0.838
QUPR	Quercus prinoides	1.92	2.30	0.321	92.94	16.650	49.70	0.578	36.74	2.525	21.74	1.882	16.09	0.935	-2.99	0.832
LITU	Liriodendron tulipifera	1.53	2.60	0.132	91.43	15.222	48.69	0.648	32.95	1.183	19.55	0.825	13.77	0.903	-1.88	0.766
PODE	Populus deltoides	1.53	2.64	0.147	82.53	1.982	48.98	0.251	30.81	1.718	19.42	0.920	12.20	0.838	-1.05	0.399
CAOV	Carya ovata	1.15	2.86	0.328	84.70	29.652	47.65	0.881	36.88	0.506	20.10	2.372	16.99	1.327	-2.80	0.975
FRNI	Fraxinus nigra	1.15	2.80	0.050	85.87	7.002	47.85	0.345	28.21	4.989	16.93	1.729	11.71	2.805	-1.29	0.807
QUMA	Quercues macrocarpa	1.15	2.82	0.198	103.91	7.179	48.91	0.465	35.61	0.766	20.87	0.793	16.09	0.144	-3.16	0.729
ROPS	Robinia pseudoacacia	1.15	3.21	0.167	64.32	6.954	48.26	0.651	35.86	1.992	23.15	1.306	16.81	0.392	-1.11	0.439
TIAM	Tilia americana	1.15	2.82	0.194	88.82	2.871	48.49	0.762	35.18	1.665	21.36	0.832	15.70	0.827	-2.50	0.417
CEOC	Celtis occidentalis	0.77	2.98	0.033	66.71	2.060	46.59	0.286	28.84	1.282	17.46	0.423	13.78	0.816	-0.74	0.208
FRPE	Fraxinus pennsylvanica	0.77	2.68	0.269	70.37	13.070	47.23	0.278	31.64	0.688	18.56	0.075	14.82	0.940	-2.99	1.068
NYSY	Nyssa sylvatica	0.77	2.40	0.065	81.28	0.948	49.62	0.358	32.22	0.217	18.00	0.034	14.22	0.224	-3.67	0.032
QUEL	Quercues ellipsoides	0.77	2.96	0.187	94.99	14.752	49.84	0.253	33.95	0.157	20.52	1.474	15.25	0.259	-3.19	0.918
CASP	Carya spp.	0.38	2.27	-	129.13	-	49.47	-	37.12	-	23.16	-	15.26	-	-1.86	-
JUNI	Juglans nigra	0.38	2.55	-	82.34	-	47.96	-	18.02	-	8.27	-	9.75	-	-1.72	-
PRSE	Prunus serotina	0.38	3.04	-	99.55	-	47.98	-	32.70	-	20.44	-	13.86	-	-1.53	-
RHCA	Rhamnus cathartica	0.38	3.22	-	84.95	-	48.11	-	33.43	-	21.59	-	14.20	-	-1.19	-

Table A3. Leaf to canopy trait aggregation schemes used in model building. Note that results from aggregation scheme A (Top of canopy) are reported in detail in the manuscript.

		Canopy weighting
Scheme	Weight	Top	Mid	Bottom
A	Top of canopy	90%	9%	1%
B	Mid-weighted canopy	64.5%	32.3%	3.2%
C	Whole canopy	40%	40%	20%
D	Only top canopy	100%	0%	0%

Fig. A1. Comparisons of PLSR coefficients obtained by fitting models to foliar traits aggregated according to different schemes described in Table A3; A (green), B (magenta), C (red), D (blue). Overlapping lines (and error estimates) indicate close agreement between all models regardless of aggregation scheme.

Fig. A2. Model fits obtained by using aggregations scheme A.

Fig. A3. Model fits obtained by using aggregations scheme B.

Fig. A4. Model fits obtained by using aggregations scheme C.

Fig. A5. Model fits obtained by using aggregations scheme D.

Fig. A6. False color composites of foliar traits (left panels; R/G/B = %ADL/Marea/%N) compared with NLCD 2006 landcover maps (right panels). Foliar trait association maps provide richer information on foliar traits across forest ecotones than discrete classes. Subplot locations are 1: Ottawa NF, MI, 2: Green Ridge SF, MD; 3: Porcupine Mountains SF, MI (boxes B, F and A in Fig. 1, Landcover classification legend is Figure A9).

Fig. A7. Foliar trait association maps (subplot 1: false color composite R/G/B = %ADL/ Marea/%Nitrogen) provide richer detail than NLCD 2006 landcover classifications (subplot 6), or from fall aerial imagery (subplot 2; 11/08/2010 GoogleEarth™). While leaf-off aerial imagery (subplot D; 4/14/2005 GoogleEarth™) clearly identifies needleleaf forest stands (also see high lignin+Marea [yellow] areas in subplot 1), color enhancement of fall aerial imagery (subplot 3) shows phenological differences (subplot 4) between dominant deciduous species (Quercus rubrum, Acer saccharum) corresponding to spatial patterns of foliar traits in subplot A. Subplot 5 indicates high confidence in mapping traits (%N, S.D. shown) across deciduous forest landcover. High prediction uncertainties are only observed in edges or non-forest areas.

Fig. A8. Recently disturbed regions show up as sharp boundaries in trait association maps (subplot 1: false color composite R/G/B = %ADL/Marea/%Nitrogen, compare with subplot 2: landcover from NLCD 2006). Changes in foliar nutrient content (%N subplot 3) and elevated uncertainties (subplot 4) capture logging activities (pre-cut subplot 5: 8/24/2007, post-logging subplot 6 10/19/2009, images from GoogleEarth™) near the Fernow Experimental Forest, WV.

Fig. A9. Legend from the National Land Cover Database 2006 (www.mrlc.gov/nlcd06_leg.php‎).

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