Agriculture Reference
In-Depth Information
a
b
Herbs
Trees
1.0
Goniothalamus macrophyllus
Diplazium cordifolium
0.8
0.6
0.4
0.2
0.0
Alocasia macrorrhiza
Cyathea contaminans
c
d
Climbers
Epiphytes
Elaphoglossum
sp.
1.0
0.8
0.6
0.4
Piper arcuatum
Asplenium cuneatum
Psychotria
sp.
0.2
0.0
0
5
10
15
20
25
30
0
5
10
15
20
25
30
Months after leaf flushing
Fig. 9.1
Leaf survivorship for 100 understory species co-occurring in a tropical montane forest
in Indonesia. Note that by exception the
Alocasia
plants that were censused grew along a riverside
opening less shaded than the other species. (
a
) Woody plants. (
b
) Herbaceous plants. (
c
) Climbing
plants and (
d
) Epipytic plants (From Shiodera et al. 2008)
species; survivorship, in turn, is consistently correlated with elements in the leaf
economic spectrum (Wright et al. 2004) as well as with aspects of foliar defense
such as condensed tannin content and leaf toughness (Shiodera et al. 2008). Ideally,
we might look for geographic pattern in the mean values of leaf longevity but the
comprehensive, community-based samples required to do so are too scarce. We turn
instead to the biogeography of foliar habit, which is rooted in leaf demography and
commands not only the long-standing interest of plant geographers but also the
attention of contemporary climate modelers.
Biogeography of Foliar Habit
As a prelude to this discussion, we should note that the geography of ecosystems
dominated by evergreen versus deciduous species has not been stable throughout
Earth's history. There are long-term influences on the patterns we see today that
are set by both the evolution of the global environment and the phylogenetic
history of contemporary plants. Both long-term changes in the global environ-
ment and the evolutionary diversification of the global flora have led to a tempo-
rally shifting mosaic in global land cover over Earth's history. Although there
