Biology Reference
In-Depth Information
Table 3.
Summary of the nectar attributes related to ecosystem post-fire succession. (Data are
from Petanidou and Ellis (1996), Potts et al. (2003, 2004), Petanidou and Lamborn (2005)).
Attributes
Freshly burnt site
(1-2 year
phrygana
)
Intermediate age
Mature pine forest
(>50 years)
(15-25 year scrub)
Nectar component
Volume*
low-medium-high
medium-low
medium
Per flower volume
relatively low
higher
higher
Concentration*
medium-high
medium
medium-low
Water content*
low-medium-high
medium-low
medium
Nectar niche diversity
high
lower
low
Energy reward*
Pollen
high
medium
low
Nectar
medium-high
medium-high
medium
Pollen: nectar
high
medium
low
Plant component
Plant diversity
high
medium
medium
Floral abundance
high
medium
medium
Plant groups
many annuals
fewer annuals
more perennials
Bee component
Diversity
high
medium
low
Abundance
high
medium
low
Guilds
Mainly short-tongued
bees; many Andreni-
dae and Apidae
Mixed guilds inclu-
ding long-tongued
bees (Megachili-
dae); fewer
Andrenidae and
Apidae
Mixed guilds; many
Andrenidae and
Apidae
* per unit habitat area
1995). Dissimilar flower shapes, therefore, differ in their nectar volume,
with gullet types secreting the highest and bowl- and head-shaped secreting
the lowest volumes. Bowl-shaped flowers possess more concentrated nectars
compared to gullet-shaped flowers (Petanidou & Smets, 1995).
Structural traits of flowers appear to play a major role in shaping nectar
characteristics, at least within a phylogenetically related group of plants.
This is true for flower size (i.e., corolla length and width) that is related to
nectary size (cf. also Chapters 3 and 4 in this volume) and nectar yield (Dafni
et al., 1988; Dafni, 1991; Petanidou et al., 2000; Galetto & Bernardello, 2004).
The size of the nectaries and nectarostomata (i.e., the openings on the nectary
