Posts from the ‘Biodiversity’ Category

Nov 4

The dynamics of inselbergs – New paper in Biological Reviews

Since the start of my PhD in 2006, I’ve spent several years of my life walking on inselbergs (i.e. ancient isolated mountains with modest topography) mainly in Africa and Australia, studying the organisms that live there. It was an inspiring and productive endeavor, leading to a lot of published case studies. Yet, some broader insights take time to develop. I believe it’s only when you spend enough time working on a system and after endless discussions with local experts that deeper understanding emerges. In 2017, a meeting was arranged at the University of Rostock, home of Stefan Porembski, arguably the most influential inselberg researcher alive today. As a PhD student I eagerly read and re-read his landmark green book on Inselbergs.

Wouldn’t it be great if we could bundle the insights that emerged in the quarter century after this book? Together with Fernando Silveira and Luiza De Paula, two (at the time) young up and coming inselberg researchers from Brazil we started drawing up some first diagrams and distilled general patterns and processes from the different plant and animal groups we studied and from the different regions we studied: from the Atlantic forest to the Kalahari and back. The paper would not have been possible without the geomorphological and biogeographical insights of Tom Van der Stocken and Falko Buschke who helped to streamline the ideas through various phases and input from a running PhD project by Joren Snoeks. We are proud that this journey now resulted in a synthesis paper published in Biological Reviews. The ecological and evolutionary dynamics of inselbergs. Some pictures of inselbergs featured in the paper are provided below.

https://onlinelibrary.wiley.com/doi/full/10.1111/brv.13150

In the paper, we provide a new liberal definition of inselbergs from a biological perspective, stressing the old age (easily tens of millions of years, often more), unique microhabitats, and isolation as the main defining characteristics. Typical inselbergs are much lower than proper mountains (< 800m) and therefore typically lack strong altitudinal zonation. They also provide a template of habitats that is not limited to the exposed rock. The surrounding vegetation fringe is an integral part of the broader inselberg ecosystem. We also stress the importance of the landscape matrix in which inselbergs are embedded, which can be a source of inselberg species. Inselbergs can house a lot of endemics adapted to the often harsh inselberg conditions. But they can also be ecological refuges and evolutionary refugia for species from the landscape matrix, particularly over long time scales of cyclical environmental change. Finally, we argue that although they resemble islands, only a small subset of the organisms that can be found on inselbergs will experience them as islands. Inselberg specialists with poor dispersal abilities will experience them as islands, while for more mobile species, inselbergs and for generalists, inselbergs may simply provide habitat patches in the broader landscape that can be used. The landscape matrix, therefore, is not simply a barrier to dispersal (as is the case for oceanic islands) but provides a pool of species and habitats that interact with species and habitats on the inselbergs. At the end, we provide a list of major knowledge gaps that may inspire the next decade of inselberg research and can help us to understand the role of these amazing features in our landscapes.

Dec 3

Biodiversity and ecosystem functioning- new paper in Ecology Letters

We tend to assume that if there are more species in a given site that this typically leads to a better functioning ecosystem with for instance a higher production of biomass. In a new paper in Ecology Letters, we show that this is invalid. It’s not how many species that are present that matters, it’s how many species that had an opportunity to be present (the regional species pool) that determines functioning.

This illustrates that we need to conserve regional biodiversity to support our ecosystem services even when local biodiversity is not declining. https://onlinelibrary.wiley.com/doi/10.1111/ele.13874

The paper is lead by James Hagan, an ex MSc student from our department at VUB and Tropimundo alumnus.

Hagan, J., Vanschoenwinkel, B. & Gamfeldt, L. (2021) We should not necessarily expect positive relationships between biodiversity and ecosystem functioning in observational field data. Ecology Letters.

Sep 3

A process based metacommunity framework – new paper in Ecology Letters

Bram was part of a working group hosted by the German Integrative Biology Institute in Leipzig that had the ambition to better understand how communities interact in space by including a much needed temporal dimension. In a first paper lead by Patrick Thompson, we present a novel framework to understand (and study) how ecological communities can interact in space and how this leads to different temporal dynamics in community data. Instead of trying to infer process from community patterns, this framework explicitly varies three underlying processes (density dependent competition, density independent environmental filtering and dispersal) and shows that by doing this a whole range of possible metacommunity dynamics can be obtained including all currently known and described dynamics as well as a range of dynamics that have remained unconsidered and unstudied.

We believe it can be an important first step to achieve a much needed synthesis in the field of metacommunity ecology.

The study was published as an “Idea and perspectives” piece in the journal Ecology Letters

https://onlinelibrary.wiley.com/doi/full/10.1111/ele.13568

Aug 18

Where does land use matter most? – new paper in Sci. Tot. Env.

The lab is active in Tanzania in an inter university collaboration with the Nelson Mandela Institute for Science and Technology in Arusha. In one of the first papers of this project, Grite Nelson shows that studies of river quality and integrity should cautiously infer the influence of surrounding land use activities. Water quality and biota responded to land use at differentn scales. What is more, the spatial buffers used to calculate land use had a strong impact on the detected land use effects. The work stresses the need to standardize approaches to investigate effects of land use on different aspects of river quality.

The paper is out in the journal Science of the Total Environment

https://www.sciencedirect.com/science/article/abs/pii/S004896971934817X

Dec 21

Workshop: Uncoupling a meaningful life from the destruction of nature

Workshop picture

In a joint VUB Global Minds project between VUB and the University of the Free State, South Africa, we generated course material that can be used to organize workshops for university students (both in developing and in developed nations) to tackle the important question of whether it is possible to lead a meaningful life without destroying nature. Participants fill out standardized scientific questionnaires that test:

1. Meaning in life (how meaningful do you find your life?)

2. Ecocentricity (how is your life connected to nature?)

3. Ecological footprint (to what extent does your life style impact nature?)

By correlating the scores of participants on these different tests our aim is to raise awareness to what extent these life traits are correlated. What is more, if applied to a large number of participants from different backgrounds and cultures it can also allow to generate more generic insights in how these concepts are connected globally. A first work shop took place at VUB on December 4th.

The supporting electronic course material can be downloaded here

and here

Below are some photos from the event

Apr 2

Mossing around

Mosses are more than just plants, for a wild variety of tiny animals, moss patches are veritable jungles. Yet, few animal ecologists have ventured into this world (but see and see). We did a first field survey to study spatial variation in biodiversity on moss islands that form on tree trunks. It was a small project that formed the BSc thesis of Mario Driesen and under supervision of Hendrik Trekels. In this pilot study we wanted to test whether typical island biogeography principles apply to moss islands. Despite the insular structure, small scale variation in isolation and island size don’t seem to matter for biodiversity. Canopy cover was the most important environmental variable. However, overall, we conclude that invertebrate composition in moss patches may not only depend on local patch conditions, in a particular moss species. It also depended on the presence of other moss species in the direct vicinity which can be dispersal sources of other species.

The work has been published in Acta Oecologica

A moss island in the Sonian forest

Mario in the field (albeit not in the Sonian forest)

Sep 2

Expedition to the Australian outback 2013

Sunset at our campsite at Walga Rock

Where we are going we don’t need roads

During the 2013 expedition we sampled a total of 600 rock pools from 50 inselbergs in Western Australia. The dataset wil be used to get more insight in the drivers of diversity patterns across spatial scales.