Invasion impact analysis of broussonetia papyrifera in Pakistan

Abstract

Phytosociological studies help to understand extent of biological invasion. The current study assessed impact of Broussonetia papyrifera invasion on native vegetation in Pothwar region of Pakistan. The approach used for study was random samplings with two categorical factors; invaded and non-invaded (control) under same habitat conditions. Differences in number of species (S), abundance (N), species richness (R), evenness (J’), Shannon diversity index (H’) and Simpson index of dominance (λ) were compared between invaded and control plots by t-test series. Control plots harbored by average of 1.28 more species per 10 m2. The control category was diverse (H’ = 2.15) than invaded category (H’ = 1.65). The higher value of species richness in control plots shows heterogeneous nature of communities and vice versa in invaded plots. The lower value of index of dominance in invaded plots shows less sample diversity than control ones. This decrease in number of species directly affects α-diversity in invaded plots. At multivariate scale, ordination (nMDS) and ANOSIM showed significant magnitude of differences between invaded and control plots in all sites. The decrease in diversity indices in invaded indicated that plant communities become less productive due to Paper mulberry invasion. This makes B. papyrifera candidate of consideration for appropriate control measures.