Biology Reference
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the 10 fragments (since these patches and landscape metrics had no variance in
Coimbra forest). Normality of all response variables were checked using Lilliefors
tests; for GLMs the percentage-expressed dependent variables were arcsine trans-
formed as suggested by Sokal & Rohlf [58].
Additionally, to examine the effect of habitat and soil type on species similar-
ity between plots these variables were considered as factors in Analysis of Simi-
larities (ANOSIM) tests [59]. Plots were ordered according to their Bray-Curtis
dissimilarities of species composition [54]. Species abundance were square-root
transformed and standardized [59] to avoid any bias resulting from very abundant
species and differences in the sample size of individuals recorded within each plot.
We also performed a Mantel test with Weighted Spearman rank correlations to
address the effect of plot geographic location on levels of taxonomic similarity.
Straight-line distances between plots were ln-transformed, as suggested by Con-
dit et al. [60] and Jones et al. [61]. The Mantel test was carried out considering
a group of 20 fragments and 75 0.1-ha plots from which information on tree
species composition is available [19], [39]. Here we assume that the lack of sig-
nificant relationships between soil type, plot location and plot floristic similarity
discard soil and plot location as variables driving the frequency of tree reproduc-
tive traits in the landscape. All analyses were carried out using SYSTAT 6.0 [62],
PRIMER v. 5 [63], and PC-ORD 4.36 [64].
Results
Reproductive Traits of Tree Species
Fragments and control plots differed significantly in more than 50% of the cat-
egories of reproductive traits investigated, but differences were much more no-
table when evaluating individuals within categories (over 60% of the categories
differed) than species (ca. 40%).
For pollination systems, fragments and control plots markedly differed in
50% of all categories (6 out of 12 categories) (Table 2; Figure 2A). The most con-
spicuous differences concerning species richness within categories of pollination
systems can be summarized in four aspects. First, fragments lacked three catego-
ries of pollination systems-pollination by birds, flies and non-flying mammals.
Second, scores for hawkmoth- and bat-mediated pollination in fragments were
about half of the scores recorded in the control plots. Third, when comparing
pollination by vertebrates as whole (birds, bats, and non-flying mammals) frag-
ments had a ca. threefold decreased frequency than control plots. Finally, frag-
ments had a 33% increase in the proportion of tree species pollinated by diverse
small insects (DSI) in comparison to control plots (Table 2). The proportion of
