Throughout April, we are featuring the articles shortlisted for the 2021 Harper Prize. The Harper Prize is an annual award for the best early career research paper published in Journal of Ecology.

Nicole Kinlock’s article ‘Uncovering structural features that underlie coexistence in an invaded woody plant community with interaction networks at multiple life stages‘ was one of those shortlisted for this year’s award.

⭐️About me

I grew up in Central New York in the U.S. and pursued a B.S. in Biology nearby at Rochester Institute of Technology. There, I had my first experiences with research in aquatic ecology and wetland restoration. A summer spent in the field sparked my interest in plant interactions, and I began to wonder about the ways neighboring plants influence one another and the community as a whole. After that, I began my doctoral studies at Stony Brook University, where I was supervised by Jessica Gurevitch.

🔎About the shortlisted paper

The shortlisted paper is a chapter of my dissertation work. In my dissertation, I sought to understand the structure of plant-plant interactions in communities in a deeper sense than could be gained by looking at pairwise interactions independently. For this chapter, I set up a field/garden experiment in an old field at the Yale Myers Forest in northeastern Connecticut in order to measure all interactions between woody species. I measured interactions at multiple life stages: between seedlings and between seedlings and adults. I used these pairwise interactions as the basis for an analysis of the network-level structure of the community.

Using this old field community as a case study, this paper highlights and maps the course for a shift in the field of plant ecology from viewing plant-plant interactions as the sum of competitive effects and responses in a community, to a more complex system of network interactions at multiple scales. I translated mechanisms for species coexistence into the corresponding network structural features that would be expected if these mechanisms are operating in plant communities. In this way, I feel the paper provides guidance for plant ecologists to adapt methods from network ecology into their work understanding the maintenance of diversity in plant communities.

Specifically, by characterizing the architecture of plant interaction networks at the scale of an entire community (comparing interactions at different life stages), the substructures that compose the network, and species’ roles within substructures, I found a mixture of both stabilizing and destabilizing network structures, involving intransitive and transitive substructures of different sizes and with different intensities among seedlings (Figure 1a,b) and nestedness in the relationships between seedlings and adults (Figure 1c,d). I also found that intransitive substructures were not exclusively stabilizing, transitive structures were not exclusively destabilizing, and the expected outcomes of interactions among species at one life stage were contrary to the expected outcomes at a different life stage. Assessing coexistence mechanisms focusing only on competitive effects or responses, only on intransitive substructures of one size, or only on a single life stage may then fail to capture the true underlying complexity in communities. Thus, the paper can provide a useful explanatory framework for understanding community stability and species coexistence.

🌱What’s next?

I am currently a postdoc at the University of Konstanz in Germany working with Mark van Kleunen. Lately, my research has been focused on broader scale phenomena—investigating the role of human influences, introduction and cultivation in particular, in determining whether plants introduced to a new area can invade (e.g., Kinlock et al. 2022). We are compiling an array of historical and present-day records of cultivated species in order to investigate these questions. Knowing the historical, human context in which naturalization and invasion take place, we are then better able to determine the influence of traits, climate, habitat, and other more fundamental ecological factors in driving invasion.

Find Nicole on Twitter and Google Scholar.

Read the full list of articles shortlisted for the 2021 Harper Prize here.