Environmental Engineering Reference
In-Depth Information
Differences between observations and prediction were also expected to arise from
the fact that the flat area where the balloon measurements were made was rather
small and surrounded by steep slopes and hills. This limitation was impossible to
circumvent because there are no flat areas in Italy where strong sabinene emitters
grow. Forest areas dominated by
F. sylvatica
and
C. sativa
are, in fact, all located
in mountain areas higher than 1,000 m. By considering these limitations, the
agreement between observations and predictions can be considered quite good and
certainly sufficient to validate the model developed to predict BVOC emissions.
3.4 Conclusions
Table
3.1
summarizes the annual emission rates for different Italian ecosystems
that were provided by the model. The validation performed on two CarboItaly
sites indicates that the model is rather accurate, suggesting that previous estimates
(Steinbrecher et al.
2009
) might have overestimated the actual emission. Due
to the resolution used and the isoprenoid specific approach followed, the model
meets the requirements to assess the impact of BVOC in the formation of ozone
and SOA. It is also suitable to assess the fraction of NPP lost as reduced carbon.
In this respect, it seems that the carbon emission as BVOC does not account for a
substantial fraction of the NPP, as it ranges from 0.03 up to 1.90 %.
−
1
)
from Italian ecosystems
Table 3.1
Annual BVOCs emission rates of isoprenoids (Gg y
Vegetation type
Isoprene
Monoterpenes
Total
isoprenoids
0.06
29.68
29.74
Forest areas covered by evergreen oaks species
(mainly
Q. ilex, Q. suber, Q. coccifera)
29.70
0.09
29.79
Forest covered by deciduous oaks (mainly
Q. cerris, Q. pubescens, Q. frainetto, Q. petraea,
Q. robur
)
Mixed forest areas covered by autochthonous
broadleaf species (mainly
Fagus sylvatica,
Castanea sativa, Acer platanoides, Fraxinus
excelsior, Fraxinus ornus, Carpinus betulus
)
-
7.26
7.26
-
1.06
1.06
Forest covered Mediterranean conifers
(mainly
P. pinea, P. pinaster, P. halepensis
)
1.08
3.20
4.28
Mixed forest covered by Mountain conifers
(mainly
P. nigra, P. sylvestris, Abies alba,
Picea abies, Larix decidua and Pinus cembra
)
Plantation of
Populus sp., Eucaliptus
and Olea europea
0.55
0.01
0.56
31.39
41.29
72.68
Total Italy
