Common invasion of non-native plant species and their co-occurrence in an urban area of Ondo State, Nigeria

Abstract

Urban development is a significant contributor to the loss of biodiversity. Biological invasion is a consequence of urban development where invasive species appear singly or in multiple following unprecedented disturbance. The current study was carried out to assess the presence and impact of the prevailing invasive non-native plant species co-habiting in the Federal University of Technology, Akure, Nigeria. Thirty-two (32) quadrants were systematically laid out to measure the species diversity and species composition of non-native plants across the University landscape. The species abundance of invasive non-native plants found within the quadrants was measured using the diversity indices. The Shannon–Wiener index (H) value was low in all the sites except Centre for Research and Development (CERAD) which was relatively high with 0.31 values. A one-way ANOVA (Duncan, P>0.05) shows that the Shannon-Wiener value and the relative density of the invasive non-native species had no significant difference among the nine selected sites; Forest Plantation (FP), Wild Park (WP), Teaching and Research Farm (T&RF), West African Science Service Centre on Climate Change and Adapted Land Use (WASKA), Centre for Research and Development (CERAD), University Senate (US), New Undergraduate Hostel (NUH), New Postgraduate Hostel (NPH) and New Road (NR). It was observed from the result that ten different instances of invasive non-native species colonized and dominated a particular study area following disturbance. In summary, it was observed that the infestation of these plant species is currently affecting the indigenous plant growth and survival at every season of the year. However, the study shows that biological control is easier done when a single species forms a colony in a site than when it is systemically spread across all areas.