| Lianas(woody vines) are woody climbing plants typical of tropical and subtropical forest that rely on trees for support in order to forest canopy.They contribute significantly to forest biodiversity and dynamics.Much of their influence on forest is likely due to their interaction with trees which are their main host plant. In the other hand, trees may represent a variety of niches to lianas, as affect lianas establishment and distribution at individual, community and ecosystem levels. The main objective of this dissertation is to explore the ecological relationships between lianas and trees.In a tropical motane rain forest in Bawangling Nature Reserve of Hainan Island (900-1000 m elevation), we investigated trees>5cm in diameter and lianas distributing on them, as well as lianas >5cm in diameter and trees climbed by them, along eight ridge transects. First, I describe the tree and liana communities in this forest.Second, I explore the association of individual tree characteristics(e.g., family, species, diameter) with liana loads on trees. Third, I analyzed the effect of liana climbing mechanisms on this association. and association between liana climbing types in pairs.The main results were as follows:(1)Mean tree (≥10cm dbh [diameter at breast height]) density at the study site(783 trees/ha) was a little higher than that of neotropical forest, but mean liana (≥2cm dbh) density (319 lianas/ha)was much lower. Basal area of trees≥10cm dbh was high (57.4 m2/ha) in comparison to other tropical forests(range=17-75m2/ha). In total 802 liana≥0.5cm individuals and 1366 tree≥5cm individuals, belonging to 48 species of 24 families and 119 species of 42 families, respectively, were found. Liana diversity, as expressed by the ratio of liana/tree species (0.4), was high in this forest in comparison to other tropical forests (0.1-0.78). Stem twining was the chief climbing mechanism, both in terms of species diversity and abundance.40.5 percent of trees>10cm in diameter carried at least one lianas, and mean number of lianas per tree≥5cm was 0.59 lianas (range 0-9, modal=1). Mean number of trees a liana≥0.5cm climbed was 1.4(range 0-9, modal=1).(2) Of 12 relatively common tree families, at least one have significantly greater and one significantly lower liana infestation rates than expected based on the mean infestation rate in this forest. Of 31 relatively common tree species,at least one have significantly greater and two significantly lower liana infestation rates than expected based on the mean infestation rate in this forest, and at least four species have significantly lower mean number of lianas per tree than mean number of lianas per tree in this forest. The probability of trees being colonized by lianas was higher in large diameter-class trees than in small diameter-classes. The mean number of lianas per tree was positively correlated with the mean branch bole height of trees.(3)Large lianas were likely to climb more host trees, as the relationship between liana dbh and host tree number was significantly correlated.The number of host trees infested by stem twiners and branch twiners was significntly related to liana dbh, but this trend was not present in tendril climbers, scramblers, or root climbers. Lianas with each climbing mechanisms climbed a similar number of trees. Root climbers climbed larger and higher tree hosts than other climbing types. Stem twiners showed a significant, positive association with other climbing types except root climbers, While, tendril climbers showed a significant, positive association with branch twiners.although, these association indices were low. Positive association between two climbing types showed a great frequency in a mechanic facilitation process in which new lianas use already established ones to climb trees.
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