Agriculture Reference
In-Depth Information
Fig. 6.6
Relationships
between leaf longevity (leaf
lifespan) and other key ele-
ments of foliar function (
Lit
data
, data reported in the lit-
erature). (From Reich et al.
1997)
1000
c
Lit data
100
Field data
10
r
2
=0.78 b=−0.66 ± 0.03
r
2
=0.75 b=−0.69 ± 0.02
e
100
10
r
2
=0.59 b=−0.34 ± 0.03
r
2
=0.60 b=−0.32 ± 0.02
1
1000
f
100
r
2
=0.57 b=−0.46 ± 0.04
r
2
=0.49 b=−0.39 ± 0.03
10
1
10
100
Leaf life-span (months)
strong negative relationship between
A
max
and leaf longevity but also a negative
relationship of leaf longevity with foliar
N
and a positive relationship with LMA
(SLA in Fig.
6.6
). Longer-lived leaves consistently have more mass per unit area,
lower concentrations of foliar
N
, and lower photosynthetic capacity, which supports
the inclusion of leaf longevity as a cardinal trait affecting leaf function.
Leaf longevity within a single biome varies about 100-fold among species, but
the broad relationships with photosynthetic capacity, foliar
N
, and LMA persist
across biomes as diverse as lowland tropical rainforest in Venezuela, subtropical
lowland shore forest in South Carolina, montane cool temperate forest in North
Carolina, desert and shrubland in New Mexico, a combination of temperate for-
est, bogs, and prairie in Wisconsin, and a combination of alpine tundra and sub-
alpine forest in Colorado (USA) (Fig.
6.7
). These areas vary greatly in mean
