Michoacán—where most of the Cuitzeo basin belongs—equivalent to
77778 tDMeq (equivalent metric tons of woody biomass in dry matter
or equivalent woody biomass suitable for charcoal making (WSC)), assuming
an average yield of kilns of about 18% (half that measured in
the study area of 31% (Ghilardi et al., in preparation). Urban population
in the Cuitzeo basin represents 26% of the State's urban total (INEGI,
2010), so we can estimate a basin's consumption of about 3640 tCh, or
an equivalent in dry woody biomass (WSC) between 11742 to 20222 t
depending on the assumed kiln's yield: 31% to 18% respectively.
The second reference comes from an ongoing study in which a
survey on charcoal use by the residential sector only (sample size=
309 households, stratified by income class) have been conducted in
the city of Morelia (Ghilardi et al., in preparation). The extrapolated
value for the whole city is around 2270 tCh, and for the entire basin
is 2806 tCh (WSC=9052–15590 t), not considering packed and
branded charcoal that necessarily comes from outside the study
area as a forest management registry is needed for branding and commercialization.
The residential charcoal consumption could be about
50% to 75% of total consumption which include restaurants and street
food vendors. Total consumption should range between 11,315
(9052×1.25) and (15590×1.50) 23385 t of WSC. Both independent
studies estimates coincide fairly well, although the second one only
considers non-branded charcoal (i.e. the first one must be a sub estimation)
and is still ongoing meaning that the uncertainty range will
be narrowed in the end. Fig. 2 shows some examples within the
study area of clearing activities for charcoal making followed by the
coppicing of oaks.