Agriculture Reference
In-Depth Information
4
M.communis C.incanus
Cistus under .Myrtus
3
2
1
a
0
4
Q.ilex:
CV
BSS
VES
3
2
1
b
0
0
200
400
600
800
1000
Decomposition time (days)
Figure 5. Fungal biomass during leaf litter decomposition of
Cistus
incanus
and
Myrtus
communis
on
top soil under their shrubs as well as of
Cistus
under
Myrtus
shrubs in a Mediterranean maquis (A) and
of
Quercus ilex
in three holm-oak woods (B) of South Italy. Data from Fioretto et al., 2000; Papa, 2000.
By comparing the mass-loss dynamics of
P. laricio
and
P. pinea
litters in the both
incubation stands, generally the decomposition rate occurred at a lower rate in the
P. laricio
than in
P. pinea
wood. This suggests that in
P. laricio
stand the dryness (P/T = 73)
superimposed the relatively low temperature, in particular in the winter (Virzo De Santo et
al., 1993).
On the other hand, the same litter of
P. sylvestris
incubated in the
P. laricio
and
P. pinea
stands as in other coniferous forest along a climatic transect North-South Europe (Berg et al.,
1993; 1995 a and b; Virzo De Santo et al., 1993) evidenced that the scarcity of precipitation
along the year and in particular in the hot summers negatively influences the decomposition
rate in Mediterranean area.
M
ICROCLIMATIC
E
FFECTS ON
D
ECOMPOSITION
R
ATE
Microbial community composition in the rhizosphere is affected by a complex interaction
between soil type, plant species and root zone location (Marschner et al., 2001). It is affected
by plant species (Pinzari et al., 1999; Miethling et al., 2000; Rutigliano et al., 2004; Fioretto
et al., 2005 b) depending on the composition of root cells and root exudates which, in turn, is
affected by root zone, plant age, N supply and mycorrhizal fungi infection (Merbach et al.,
1999). In addition, soil aeration and physical-chemical characteristics result in different
microbial communities and spatial variability (Gelsomino et al., 1999; Carelli et al., 2000).
