Data from: Changes in liana density over 30 years in a Bornean rain forest supports the escape hypothesis

In two permanent plots of lowland dipterocarp forest at Danum a liana
census in 1988 was repeated in 2018 using the same method. Trees ≥ 30 cm
gbh (girth at breast height) were recorded for number of lianas ≥ 2 cm gbh
on their stems. The forest was evidently in a late stage of recovery from
a large natural disturbance. Over the interval, mean number of lianas per
tree decreased by 22 and 34 % in plots 1 and 2. By 2018 there were
relatively more trees with few lianas and relatively fewer trees with many
lianas than in 1988. The redistribution was strongest for overstorey trees
of the Dipterocarpaceae (more with no lianas by 2018) and understorey
trees of the Euphorbiaceae (many losing high loads in plot 2). 
Proportion of trees with lianas rose overall by 3.5%.  Number of
lianas per tree showed a quadratic relationship with tree size (ln[gbh]):
maximal for large trees, fewer for smaller and very large trees. Tree
survival and stem growth rate were significantly negatively related to
number of lianas, after accounting for spatial autocorrelation. Monte
Carlo random samples of half of trees in 1988 were compared with the other
half of trees in 2018. Relative frequency distributions differed
significantly over time, but dipterocarps and euphorbs varied noticeably
in their liana dynamics between plots. Regressions achieved best
significant fits when number of lianas was a function of date, ln(gbh) and
ln(gbh)2, but differently in the plots reflecting complicated host-liana
dynamics. Analysis of most abundant trees species, individually,
highlighted a group of emergent dipterocarps with low liana counts
decreasing with time. Building on an earlier hypothesis, these trees lose
their lianas with branch shedding, as they move into, and emerge from, the
main canopy. They escape from the parasite. The process may in part
explain the uneven nature of the forest canopy at Danum. Change in liana
density was contingent on forest history and site succession, and
plot-level structure and dynamics. Liana promotion in intermittent dry
periods was seemingly being offset by closing of the forest and continued
dominance by the Dipterocarpaceae.