Biodiversity of Lianas and Their Functional Traits in Tropical Forests of Peninsular India

Abstract

The present study was aimed to investigate the diversity and functional traits of lianas in four tropical forest types of peninsular India. The work also intended to study the variation in the proportion of lianas with trees along an altitudinal gradient and to compare the functional traits of lianas and trees sharing similar environmental conditions. All lianas ≥ 1.5 cm diameter and trees ≥ 10 cm diameter at breast height were measured and included the inventory. A total of 237 liana species were enumerated across the four forest types. The species richness of lianas per hectare was maximum at semi-evergreen forest (31 ± 5.3) and minimum at dry evergreen forest sites (21 ± 3.9). Semi-evergreen forest sites of Eastern Ghats also had the highest density (648 ± 152.7 ha−1) of liana stems and wet-evergreen forest sites of Western Ghats registered the lowest (261 ± 86.7 ha−1). Dry evergreen forest sites on the Coromandel Coast recorded the highest basal area (0.75 ± 0.44 m2 ha−1) and the above ground biomass (22.77 ± 19.1 Mg ha−1) of lianas across the study sites followed by the semi-evergreen forest sites (0.69 ± 0.3 m2 ha−1 and 10.01 ± 6.2 Mg ha−1). The proportion of liana species richness to total woody species decreased along the altitudinal gradient in the present study. Majority of lianas in the study sites were brevi-deciduous by plant type except in wet-evergreen forest sites. Stem twining was the chief climbing mechanism by species richness and scramblers formed the most abundant liana group by abundance. Majority of lianas had microphyllous leaves, whereas trees had mesophyllous leaves as their predominant leaf type. Flowers of SEF and SDF sites were mostly conspicuous, while the flowers of DEF sites were largely inconspicuous. Dispersal by animals (biotic) formed the major diaspore dispersal strategy of lianas in four tropical forest types of peninsular India.