Field-independent carbon mapping and quantification in forest plantation through remote sensing

Figures & data

Figure 1. The study area (blue) and sample plots (red). Bottom-left, the density distribution of the CO₂ equivalent in the 20 plots measured on the ground.

Table 1. Parameters used in the different strategies by progressively increasing the level of plantation knowledge. The FI model requires the information available for user d. The information available for users a, b, and c are used to obtain the information available for user d as detailed below.

User	Plantation available information
a	Tree Species	Planting Density	Age	Site index
b	Tree Species	Planting Density	Average DBH
c	Tree Species	Planting Density	Average DBH	Average Height
d	Min, mean, and max CO2 equivalent

Table 2. Parameters for estimating the diameter of switenia macrophylla and cedrela odorata (INB, 2019a, 2019b).

Tree species	α	β	γ	δ
Switenia macrophylla	1.724193	2.74867	0.0838	0.000075
Cedrela odorata	2.186717	2.865757	0.079924	0.000238

Table 3. Data used for the different strategies by progressively increasing the level of plantation knowledge and thus of information available to calculate the parameters required by the FI approach: min, mean, and max CO₂ equivalent in the plantation. User d is not reported as it is the benchmark in which min, mean, and max CO₂ equivalent in the plantation are known.

User	Age	Tree Species	Density (N h^−1)	Site index	DBH (cm)	H (m)
a	21 months	S. macrophylla C. odorata	1111	14.7 12.4
b		S. macrophylla C. odorata	1111		4.34 4.10
c		S. macrophylla C. odorata	1111		4.34 4.10	3.81 3.69

Table 4. Comparison of the results achieved using the DB, MA, and FI carbon mapping and estimation methods. For the DB estimation methods RMSE% and r² are not available as it provides just estimates and not maps. For the FIs methods, confidence intervals are not available as they are based just on remote sensing data, and reference data is not used.

Estimation method	CO2 equivalent (MgC)	RMSE%	r^2
DB	100.5 ± 18.2*	–	–
MA	102.0 ± 8.2*	38.7	0.1
FIa	89.3	39.6	0.3
FIb	117.4	41.9
FIc	102.3	37.3
FId	108.5	34.1

*95% confidence interval estimates.

Figure 2. Top, map of CO₂ equivalent obtained with FI method with different CO₂ equivalent ranges (MgC ha⁻¹) depending on the FI case. Bottom, map of CO₂ equivalent obtained with the MA method. Empty pixels correspond to outliers and were masked out.

Figure 3. Medoid predictors’ importance assessment in terms of mean square error percentage increase.

INB. (2019a). Paquete Tecnologico Forestal Cedrela odorata L. Departamento de Investigación Forestal.

 Google Scholar

INB. (2019b). Paquete Tecnológico Forestal para Caoba de Petén Swietenia macrophylla King versión 1.0. Departamento de Investigación Forestal.

 Google Scholar