Paired plot experiments to assess impact of invasive species on native floral diversity in Pakistan

Abstract

The threat of invasion is growing globally and endangers biodiversity. Exotic invasive plants are putting a harm to the vegetation of Pakistan’s Pothwar region, which is a biodiversity hotspot. In the current study, the effects of Broussonetia papyrifera, Parthenium hysterophorus, Xanthium strumarium, and Lantana camara on the local flora in the Pothwar area were examined. Two categorical groups (invaded and non-invaded) were used in a dichotomized experimental design to collect data. Using the software PRIMER-7 and IBM SPSS v. 21, different diversity indices including Margalef’s index of species richness, Shannon index of diversity, and Simpson index of dominance were measured and compared between invaded and control plots. In comparison to the experimental plots, the control plots had an average of more individuals and diversity. On a multivariate scale, non-metric multidimensional scaling (nMDS) and analysis of similarity (ANOSIM) revealed higher species richness in control plots. The invasion effect of L. camara was the highest, followed by X. strumarium, P. hysterophorus, and B. papyrifera.

Plant Species Richness and Invasional Meltdown in Different Parts of Acer negundo L. Secondary Range

“…There are fewer works describing the opposite result when plant invasions did not decrease or even increase plant species richness in recipient communities [6]. The plant richness decrease was found both in paired block experimental designs, i.e., in works comparing invaded and non-invaded communities [65], and in designs assessing community responses to invasion throughout the invader abundance gradient [5,66]. In our case, the effect of A. negundo invasion was detected not only when comparing the dominated by A. negundo (invaded in our study) communities and the communities without its domination (non-invaded in our study).…”