How a class of students published a paper about plant cover’s relationship to biomass

The post provided by Xiaobin Pan, Nathan Ferris and Jan Lepš

This post refers to the article The convex relationship between plant cover and biomass: Implications for assessing species and community properties by Pan et al. published in the Journal of Vegetation Science (https://doi.org/10.1111/jvs.13288)

Šuspa (Jan Lepš, senior author, who designed and conducted the fieldwork):

In 1994, I established a management experiment in an oligotrophic wet meadow, which included a factorial combination of mowing, fertilization and dominant removal. In addition to management questions (showing the effect of mowing and fertilization), the main theoretical aim was to experimentally test if competition is stronger in high or low nutrient conditions, at this time hotly debated between J. Philip Grime and David Tilman. Originally, the experiment was planned for three years. Nevertheless, because we did not manage to publish the three years’ results before the fourth season, I decided to sample during the fourth season as well, and so it has gone on for 30 years (the project is still running). There are nice recommendations for how you should establish a long-term project. However, from what I have seen, long-term projects are often established as short-term ones, and continued on the initiative of individuals rather than institutions. I must admit that I would have done some things differently if I had planned it as a decades-long experiment.

One of the fundamental questions in the experiment was selection of the monitoring method. In my view, collecting and weighing biomass is the most objective method, but it is destructive. It can be used as a “simulation” of mowing, so we have biomass data from permanent mown plots, but not from unmown. Because we needed to compare mown and unmown plots, in all the plots, cover was estimated using a grid (as described in this new paper). Thus, in the mown plots, we have exactly the same quadrats monitored for many years with the two methods used most frequently in plant community monitoring. I had been aware for many years that their comparison would be useful, but other analyses always seemed more urgent. I was aware that the relationship could not be linear and thus, there must be some systematic differences in the results of the analyses. I sincerely hoped that most of the results would show similar outcomes, but at the same time, I was afraid, what if they didn’t :-)?

In 2011, we started to organize our Quantitative Ecology Module (https://botanika.prf.jcu.cz/quantecol), running the winter semester of odd years. The module is attended by students from universities around the world (EU students usually get Erasmus or similar support). One of the courses we started for the module is Creative Publishing in Community Ecology. In this course, senior tutors provide groups of students an “orphaned dataset” (i.e. data that they consider valuable but that, due to lack of time, simply sits in their drawer – or, more likely, on their hard disk). The tutors provide some ideas for questions that could be asked and how the data could be analysed, and let the students write a real manuscript under their supervision. All of this is in the spirit of practice being more valuable than theory for acquiring any skill. The manuscript is submitted and finally published with the basic rule that the first author must be a student. The course is quite popular and, since 2019, is also frequently attended by students of our international Master’s program in Ecology (https://www.prf.jcu.cz/ecology).

For the 2023 run, I recalled this topic comparing cover and biomass, as described above and thought it would be interesting not only for the students, but also for myself. We (me and fellow tutor Jenda Hrček) got an excellent group of students, and our paper is the twelfth published from this course (see https://botanika.prf.jcu.cz/suspa/vyuka/creative.php for a complete list).

Xiaobin (Xiaobin Pan, co-first author and PhD student attending the Quantitative Ecology module):

I was advised by my co-supervisor, Francesco de Bello, who is also one of the organizers (more information can be found at https://functionaldiversitylab.com/) to join the quantitative ecology module. Following his recommendation, I enrolled and found it incredibly interesting and immensely useful. This paper is actually a reward of the course ‘Creative Publishing in Community Ecology,’ which I participated in.

During the first class, the teachers presented three topics from which we could choose. Given that my PhD project focuses on species diversity and community stability, I opted for Šuspa’s topic. What made Šuspa’s topic particularly compelling was the availability of 14 years of cover and biomass data from the same plots. This long-term dataset provides a unique opportunity to explore numerous intriguing research questions.

Leveraging the comprehensive data and integrating the knowledge I gained from other courses in this module, my peers and I swiftly completed all necessary reviews of the literature, analyses, and writing. Our findings indicate that the relationship biomass = Function(cover) is a convex function. This insight is crucial for ecological research and contributes to a deeper understanding of how different methodologies can influence ecological metrics.I am deeply grateful for the opportunity to engage in this subproject during my PhD. Working alongside Suspa and other peers has been a rewarding experience, allowing me to broaden my research horizons and gain invaluable collaborative experience. This project not only enriched my academic journey but also provided practical insights that will be beneficial in my future research.

Nathan (Nathan Ferris, co-first author and Master of Ecology student):

Master of Ecology students at the University of South Bohemia have a somewhat unique opportunity in that we are offered a course about successfully publishing papers. As part of this course, our professors invite us to collaborate on papers outside of our thesis work. It’s a great opportunity to work in a new discipline, get feedback on our analysis and writing skills and, of course, potentially get published. This prospect was especially exciting to me because I was new to the field of ecology. My bachelor’s is in engineering so although I am no stranger to experimental design and the scientific method, the natural complexity and lack of complete environmental control found in ecology was relatively new to me. This year’s course offered three projects to choose from. When I asked to work with Šuspa, I was simply hoping to get some writing experience and gain a little confidence before attempting to compose my own thesis. I could not have predicted that I would become one of the first authors, nor the degree to which I would deepen my skills as a scientist and author. Most importantly, the subject matter of this paper turned out to be very relevant to my area of interest.

My main interest and motivation behind pursuing this field is ecological restoration and conservation, where monitoring is a crucial but often overlooked aspect. Without monitoring, there is no evidence to claim confidently that restoration or conservation has worked. Not only that, but it is often a requirement for access to various funding sources and permits. The findings of this paper will help people on both theoretical and practical sides of the discipline to better interpret and debate key metrics like community diversity, and I am very proud to have played a part in that.

Brief personal summaries:

Jan Lepš started his career as a student of vegetation ecology, studying old-field succession under the supervision of Marcel Rejmánek. He is an ecologist teaching at the Faculty of Science, University of South Bohemia, Czech Republic. He leads the Functional Plant Ecology group at the Department of Botany (https://botanika.prf.jcu.cz/fpe/), and is interested in a wide range of topics, which include species coexistence, mechanisms of maintenance of diversity, effects of diversity on community functioning, methods of ecological data analysis, and vegetation dynamics, among others. Besides his work in temperate species-rich grasslands, he has worked in the tropical forests of Papua New Guinea, and analysed data from a wide range of ecosystem types.

Xiaobin Pan is a PhD candidate of the Ecology and Biodiversity group from Utrecht University. With the help of plant functional traits, he aims to contribute to a better understanding of the complex relationship between plant diversity and ecosystem functional stability in the face of global environmental change, ultimately informing policies and management strategies aimed at safeguarding our planet’s precious biodiversity.

Nathan Ferris is a wetland ecologist and Master of Ecology student at the University of South Bohemia interested in ecological restoration and conservation. His current focus is the effects of wetland hydrology on the survival of wetland grasses and sedges. More general interests include riparian restoration, interactions between native and exotic invasive plants (allelopathy, legacy effects, plant-soil feedbacks), and the control of invasive species.