Climate Change Mitigation - Soil Carbon: Science, Management and Policy for Multiple Benefits - page 128

field level, but might at the same time rep-
resent a good mitigation strategy at the
landscape, or even national, level. For ex-
ample, while agronomic intensification
at the field scale to increase production
could increase emissions locally, it is evi-
dent that at a regional level, increasing
production in areas capable of high crop
productivity will reduce conversion pres-
sure on other land (forest/savannah deg-
radation) and reduce GHG emissions at
the regional scale. Thus, at a regional level,
increased access to fertilizers for farmers
can be a candidate mitigation solution
compared to other alternatives (reduced in-
tensification, higher dependencies from
importation, additional land degradation).
This is particularly important in develop-
ing countries where, erroneously, nitrogen
fertilization is in most cases considered
only as an N 2 O emissions source. Burney
et al . (2010) demonstrated the importance
of taking into account a landscape dimen-
sion when identifying cost-effective ways
to avoid GHG emissions. Future agricul-
tural productivity is critical, as it will
shape emissions from the conversion of
native landscapes to food and biofuel
crops. However, the Burney et al . (2010)
analysis noted that investment in agricul-
tural research was rarely mentioned as a
mitigation strategy. Based on their esti-
mates of the net effect on GHG emissions
of historical agricultural intensification
between 1961 and 2005, they found that
while emissions from factors such as fer-
tilizer production and application had
increased, the net effect of higher yields
meant an overall decrease in GHG emis-
sions. Their figures show that each dollar
invested in agricultural yields has re-
sulted in 249 fewer kg CO 2 -eq emissions
relative to 1961 technology, and that in-
vestment in yield improvements compares
favourably with other commonly proposed
mitigation strategies. This analysis is par-
ticularly important for countries that need
to increase food productivity at the na-
tional level. However, the problem re-
mains of how to quantify the impact of
national policies or of the implementation
of field plot technical solutions at the

landscape level. The bioenergy debates
have shown that land-use change (LUC) is
critical for environmental assessment.
LUC includes direct LUC (dLUC), occur-
ring in the study area itself, and indirect
LUC (iLUC), occurring outside the study
area but resulting from changes within the
study area. Lapola et al . (2010) reported
that iLUC could, in certain cases, over-
come carbon savings from biofuels. Dur-
ing recent years there has therefore been
an increasing demand by project man-
agers and policy makers for suitable GHG
assessment tools to reap the benefits of a
landscape-scale approach. The IPCC has
published guidelines and good practices for
GHG accounting (Eggleston et al ., 2006),
and various tools have been developed to
help those performing GHG assessment
within these guidelines. Denef et al .
(2012) classified these tools into calcula-
tors, protocols, guidelines and models.
Two recent publications (Colomb et al .,
2013; Milne et al ., 2013) showed that
many calculators were available for
landscape-scale assessment to meet differ-
ent needs (and cover different parts of the
world). The level of uncertainty of the
appraisal performed with those tools re-
mains high, but is acceptable so long as
the aim is mainly to raise awareness,
guide policy decisions and demonstrate
synergy between development and mitiga-
tion (Branca et al ., 2013b).

Conclusion

SCS should be seen not only in a mitigation
perspective but also better in a wider ap-
proach considering other ecosystems bene-
fits and optimization of the trade-offs ( Fig. 9.3 ) .
Promoting better C management will be a
multiple-win solution: for the global scale
and the climate systems, for the local scales
and the fight against soil degradation, and
for the achievement of food security at all
levels. The mobilization of local solutions
for SCS will be possible at larger or even
global scales, only if SCS is considered for
all its co-benefits.