Why we need plant data from the Afromontane grasslands of Maloti-Drakensberg, South Africa?
The Afromontane region supports a global biodiversity hotspot with high levels of endemism. These mountain ecosystems have served as biodiversity refugia during periods of past climate variations, but are now under threat from the compounding effects of biological invasions, land-use change, and climate change. Our data provide the first recorded trait data for 47 vascular plant species and more than double the trait data coverage from the Maloti-Drakensberg (106% increase). This study offers insights into plant and ecosystem functioning, provides a baseline for assessing impacts of environmental change, builds local competence, and aligns with similar data from China, Svalbard, Peru, and Norway. This dataset was collected as part of an international Plant Functional Traits Course.
What are the main contents of the dataset?
In 2023, we collected comprehensive trait data in five sites along a 800 m elevation gradient from 2000–2800 m a.s.l. and in a climate warming experiment at 3064 m a.s.l.. This paper reports on 1 038 plant observations, 24 405 aboveground and 94 root trait measurements from 171 vascular plant taxa paired with 11 other datasets reflecting vegetation and structure, leaf and ecosystem carbon and water fluxes, leaf hyperspectral reflectance, and microclimatic and environmental data. This research follows best-practice approaches for open and reproducible research planning, execution, reporting, and management. The experimental design and data collection follows community-approved standards. The data are cleaned and managed using script-based workflows that ensure reproducibility and transparency.
How does this study relate to biodiversity change?
By making these data available, we aim to contribute towards a better ecological understanding of Afromontane grassland ecosystems and facilitate research on the Maloti-Drakensberg socio-ecological system. The course provided opportunities for local capacity building, contributing to a regional community of practice for southern African mountain research, conservation, and management, including to the Mont-aux-Sources Long-term Social-Ecological Research Site (MaS LTSER) in the northern Maloti-Drakensberg, the Maloti-Drakensberg Transfrontier Programme, and local conservation and livelihood creation initiatives such as the proposed indigenous community-led Witsieshoek Community Conservation Area.
The data set has been peer reviewed and it is published as an open access article, which is available in the link below.
Author of the blog post: Julia Kemppinen
Why plant trait values and species abundances should be jointly modelled?
Plants respond to their surrounding environmental conditions. This response is reflected in their traits, such as height and leaf properties, and all this contributes to within-species variation. Within-species trait variation can play a major role in driving the assembly of plant communities, however, the links between this trait variation and community assembly remain insufficiently understood. More importantly, we have lacked models that could jointly predict and statistically link trait values and species abundances. Such models would be much needed to better understand the complexity of the mechanisms through which within-species trait variation shapes plant communities.
What are the main results of the study?
We extend the joint species distribution modeling (JSDM) framework into the joint species-trait distribution modeling (JSTDM) framework to explicitly link species abundances to phenotypic variation in traits for multiple species simultaneously. We used trait and abundance data of 65 tundra plant species to show how the JSTDM approach (1) estimates the statistical associations among species abundances, species-level traits, and site-level traits, relative to environmental variation; (2) improves predictions on trait variation by using information on species abundances; and (3) generates hypotheses about trait-driven community assembly mechanisms.
How does this study relate to biodiversity change?
JSTDM allows assessing the interplay between species abundances and traits at the community level, providing the much needed modeling tools to quantify the role of phenotypic trait variation in eco-evolutionary community assembly. We applied JSTDM also for investigating if traits influenced the abundances and richness of the neighboring species. Here, we used Empetrum nigrum as an example species, as it is well known to affect the performance and composition of the neighboring plant communities and its abundance as profoundly increased in northern European tundra as a consequence of rapid climate change.
The study has been peer reviewed and it is published as an open access article, which is available in the link below.
Author of the blog post: Julia Kemppinen
What is a functional composition of a plant community?
Plant communities consist of individuals and species that occur together. Each individual and species of the community can be quantified based on its functional traits, such as height or leaf area. So, the functional composition of a plant community refers to the variety and abundance of plant species based on their functional traits, rather than just their taxonomic identity (their species names). Functional traits influence how plants grow, survive, and reproduce, and how they interact with their environment, such as nutrients.
What are the main results of the study?
We compared the functional composition of plant communities between two sites in Svalbard. One site was heavily influenced by the nutrient input from a seabird colony that was nesting above the site. We assessed 13 different functional traits and found that plants closest to the colony, were taller and had higher resource-acquisitive trait values, such as larger and thicker leaves and higher leaf nutrient contents. At the site close to the colony, we found different species with different functional traits, and overall, we found a lot of within species variation based on their functional traits.
How does this study relate to biodiversity change?
Seabird populations are globally declining, and this has been a very rapid and dramatic decline in the Arctic. Declining bird populations affect the marine-derived nutrient input that birds bring from the sea to land. This in turn influences the vegetation at and nearby seabird colonies, and if bird populations continue declining, so will their nutrient inputs. Arctic plants are already showing responses to increasing warming, and one of the key indicators of this are their functional traits, such as plant height. As the climate changes in the Arctic, this will have consequences to plants not only directly through warming, but also through the declining nutrient input from seabirds.
The study has been peer reviewed and it is published as an open access article, which is available in the link below.
Author of the blog post: Julia Kemppinen
What is microclimate?
Microclimate refers to the local climatic conditions that matter to all organisms from humans to other animals and plants. For instance, in heat waves and storms, animals seek for shade or shelter to accommodate their microclimate preferences. Even in less dramatic settings such as in an office space, the local temperature and moisture conditions really do affect how the office plants and humans live and survive. This is why microclimates are important to measure and there are many ways to do so.
What are the main results of the study?
This article is a review of the most useful ways to measure microclimates. The article explains why, what, how, when, and where to measure microclimates and it also summarises what to consider when analysing and publishing microclimate data. These matters are important to evaluate, because there is no one-solution-fits-all when it comes to measuring microclimates. Microclimates should be always measured considering the specific study object, the study area, and the study question. For instance, an elephant in the savanna and a tiny plant in the tundra are both dependent on the local temperature conditions around them. But the same measurement techniques and scales do not necessarily work on both study objects because the ecology of an elephant and a plant is very different and because the savanna and the tundra are such different ecosystems.
How does this study relate to biodiversity change?
Biodiversity refers to the diversity of all living things, including for instance genetic variability and the diversity of species and ecosystems. All this biodiversity on Earth is affected by climate change, and measuring microclimates is an important tool in research for understanding how exactly things are responding to climate change. Because after all, all living things are affected by their surrounding conditions, including their microclimates. So, as the overall climate changes, it also changes the microclimates in which all organisms live.
The study has been peer reviewed and it is published as an open access article, which is available in the link below.
Author of the blog post: Julia Kemppinen