A Field Investigation into the Effects of Anthropogenic Disturbances on Biodiversity and Alien Invasions of Plant Communities

Oct 15, 2026

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Biodiversity underpins ecosystem services essential to human well-being, yet human activity can alter it through anthropogenic disturbances. This paper presents a field-activity protocol and results from a non-majors’ biology course where students surveyed plant species across five sites with different disturbance regimes. Disturbances reduced species richness, evenness, and diversity, and increased vulnerability to alien plant invasions. The approach is presented as adaptable for ecology, conservation, and botany instruction.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages12

Reading Time30 min

AccessFree to download

Abstract

Introduction

Biodiversity and conservation biology

Disturbances and their ecological role

Natural vs. anthropogenic disturbances

Effects on community diversity

Disturbances and alien invasions

ARTICLE A Field Investigation into the Effects of Anthropogenic Disturbances on Biodiversity and Alien Invasions of Plant Communities Michael J. Wise1 1Department of Biology, Roanoke College, Salem, VA 24153 [Corresponding Author:](Corresponding Author: wise@roanoke.edu)[ wise@roanoke.edu](Corresponding Author: wise@roanoke.edu) Abstract: The importance of biodiversity to the health of our planet is increasingly being discussed, not only by scientists, but by the public at large. Therefore, an understanding of how human activities are affecting biodiversity is vital for informed participation in society, and thus it is an important topic for liberal arts education. Here, I present the protocol and results for afield activity that I have used in a non-majors ’ biology course to investigate the influence of anthropogenic disturbances on plant communities. Students surveyed plant-species abundancesin five sites that had experienced a range of disturbance regimes, including protected nature trails, mowed fields, and a ruderal (waste) site. Disturbances had a negative impact on measures of species richness, evenness, and diversity; moreover, disturbances made the plant communities much more susceptible to invasion by alien species. While the approach taken in this study worked very well in my non-majors’course, it could easily be adapted and refined for use in ecology, conservation, and botany courses for biology majors. Keywords: biodiversity, conservation, disturbance, evenness, invasive plants, Simpson’s index, species richness INTRODUCTION The scientific focus of conservation biology is on principles related to the protection of biological diversity, or“biodiversity.” Biodiversity can be studied on a wide range of scales, from genetic variation among individuals of a species to the diversity of biomes across the globe. A particularly important scale is the community level, or the mixture of individuals of different species that occur together in the same location. The identities and relative abundances ofthe species within a community define the community’s“structure,” and the co-occurring species plus the abiotic aspects of the location constitute an “ecosystem.” This paper reports on a field study conducted by a nonmajors’ biology course in which students measured plant-community structures and investigated how biodiversity was related to anthropogenic activities. Biodiversity is a central focus of conservation largely because of its influence on the processes needed to maintain ecosystems so that they can provide services necessary for human well-being (Sekercioglu, 2010; Cardinale et al., 2011; Hooper et al., 2012; Liu, 2016; Thom & Seidl, 2016) . These ecosystem services include water purification, flood control, pest control, carbon sequestration, decomposition, and pollination. Ecosystems also provide goods to humans, such as food, timber, biofuels, and medicine. More abstractly, biodiversity in ecosystems provides aesthetic, recreational, cultural, and even spiritual value to humans. Because biodiversity affects so many different aspects of our lives, even students with minimal interest in biology can find some reason to care about biodiversity. Foremost among the factors believed to drive changes in biodiversity are what ecologists call “disturbances,”which are defined as events that cause abrupt changes in the physical and biotic characteristics of an ecosystem, displacing or killing some or all of the individuals of some species and creating new opportunities for others (Sousa, 1984; Pickett & White, 1985; van der Maarel, 1993) . Disturbances can be natural in origin (e.g., winds, floods, fires, waves, ungulate browsing, and pest outbreaks) or anthropogenic (e.g., logging, mining, agriculture, fires, dredging, and pollution) . In addition, anthropogenic changes to the environment are increasing the frequency and severity of some natural disturbances, such as hurricanes, floods, and extremetemperat

FAQs

What question does the study investigate?

The study investigates how anthropogenic disturbances influence plant-community biodiversity and how those disturbances affect susceptibility to alien plant invasions.

How was the field activity conducted?

Students surveyed plant-species abundances at five sites representing a range of disturbance regimes, including protected trails, mowed fields, and a ruderal (waste) site.

What were the main findings about biodiversity?

Disturbances had negative effects on species richness, evenness, and diversity, and they made plant communities more susceptible to invasion by alien species.

Oct 15, 2026

Upload by Ben