The study focuses on understorey–overstorey plant community dynamics in a dry tropical forest to facilitate appropriate management
decisions. We compare community composition and species diversity of the understorey vegetation among five dry tropical forest sites in
northern India. A total of 1500 quadrats distributed over 15 one-ha permanent plots in five sites differing in the degree of disturbance,
were used to enumerate the understorey tree species and the results were compared with overstorey tree layer. The non-metric
multidimensional scaling (NMS) ordination revealed that human disturbance intensity, as well as the overall disturbance regimes, and
soil water holding capacity controlled the organisation of dry tropical forest understorey composition through effects on soil organic
matter. The a-diversity and its components decreased with increasing human disturbance intensity, reflecting utilisation pressure and
decreased soil fertility, as also revealed by the analysis of overstorey tree layer. There was a significant positive relationship between
overstorey and understorey diversity. Results suggest that in the future, the existing understorey tree communities may replace the
current dry tropical forest communities under prevailing environmental conditions. The study also asserts that the rate of species
accumulation will be greater in more disturbed sites as well as at small spatial scale within each disturbance level.
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