Can microclimate refugia save an iconic floral assemblage under climate change?

only can we improve our understanding of historical biological responses to climate change, but we can also improve our forecasts of change and inform meaningful actions to conserve species under environmental change.

Teesdale in the North Pennines of the UK represents a living laboratory and a nationally exceptional floral assemblage. The assemblage comprises southern species at their northern range limit juxtaposed with northern species at their southern range limit: in other words, ecologically remarkable species living at the margins of their suitable climatic envelope (3). As the climate warms, we would expect that the northern species would be lost and that southern species would advance, yet evidence suggests that this rarely happens as we expect and that microclimates provide refugia that buffer change (4,5). Given the variable microtopography and geology of this upland landscape, there likely exists microclimates that provide such refugia, but climate is not the only driver of change. The Teesdale fells have been grazed by sheep for generations, and as sheep numbers change, so does the vegetation and its distribution. The extent to which climate change and sheep grazing interact to determine the fate of the Teesdale flora is not understood and could hold the key to both conserving these rare plants on a local scale, and to a better understanding of climate/land-use interactions on a global scale.

An ambitious component of this project is establishing microclimate and vegetation monitoring plots in a fractal sampling design (6) that captures the full spectrum of microclimate space (7), following the guidelines of and feeding data into the MicroFractal Network: https://ecofracnetwork.github.io/protocol/. This study design is key in allowing us to identify not just biological and microclimatic variation across the landscape and through time, but also how these patterns change across scales. In this way, we can quantify the degree of spatial homogenisation, as well as the importance of microhabitats and microclimates for supporting unique flora that are otherwise rare at the landscape scale, which is likely to be those species at the limits of their climate niche.

Microclimate typically deviates from the ‘macroclimate’ of the landscape because of fine-scale variation in two factors: vegetation and topography. Thus, at the same monitoring plots we will use cutting edge techniques to quantify vegetation structure through time using phone-based LiDAR, potentially combined with drone-based LiDAR to assess vegetation structure and topography of the whole landscape. This will facilitate extrapolation of results from the plot-level, to characterise the spatiotemporal distribution of microclimates across the landscape and to identify possible refugia for rare plant species.

The final component of fieldwork requires monitoring sheep movement patterns across the site, to understand where they are spending time and the extent to which this may interact with microclimate to determine plant species distribution at fine scale. We will select a representative sample of sheep for tracking using combined GPS data loggers and triaxial accelerometers. GPS telemetry will provide data on fine scale movement and location, whilst accelerometry will provide scope for developing automatic classification of behaviours with respect to time and location.

It should also be noted that microclimate monitoring and botanical surveys have been underway in this landscape for decades, providing a rich and ready source of historical data. There are also long-running experimental plots investigating warming and grazing impacts. These existing datasets act to mitigate the risks of fieldwork, as well as providing exceptional historical data to complement newly collected data.

Throughout the project, the student will work closely with the Senior Reserve Manager at Natural England and with local landowners to ensure that the project not only runs smoothly but also retains local relevance for the end users who manage this landscape.

Funding Notes

This project is in competition with others for full funding (fees, stipend and a generous research support and training budget). Interested international applicants must contact the supervisor with a CV and covering letter by no later than Monday 7th December (12pm, UK time).

In order to address historical imbalances in the higher education sector, Iapetus is committed to recruiting a diverse, representative community of researchers in Environmental Science. The DTP has developed an Equality, Diversity and Inclusion policy to further this. This includes the Widening Participation Scheme, which identifies Home applicants from underrepresented groups. Also, we are pleased to introduce the Iapetus Diversifying Talent Scholarship Scheme, a separate competition designed for those from underrepresented groups. For more, please see the Iapetus website.

References

1. Maxwell, S.L., Fuller, R.A., Brooks, T.M., Watson, J.E.M., 2016. Biodiversity: The ravages of guns, nets and bulldozers. Nature News 536, 143. https://doi.org/10.1038/536143a
2. Kemppinen, J., Lembrechts, J.J., Van Meerbeek, K., Carnicer, J., Chardon, N.I., Kardol, P., Lenoir, J., Liu, D., Maclean, I., Pergl, J., Saccone, P., Senior, R.A., Shen, T., Słowińska, S., Vandvik, V., von Oppen, J., Aalto, J., Ayalew, B., Bates, O., Bertelsmeier, C., Bertrand, R., Beugnon, R., Borderieux, J., Brůna, J., Buckley, L., Bujan, J., Casanova-Katny, A., Christiansen, D.M., Collart, F., De Lombaerde, E., De Pauw, K., Depauw, L., Di Musciano, M., Díaz Borrego, R., Díaz-Calafat, J., Ellis-Soto, D., Esteban, R., de Jong, G.F., Gallois, E., Garcia, M.B., Gillerot, L., Greiser, C., Gril, E., Haesen, S., Hampe, A., Hedwall, P.-O., Hes, G., Hespanhol, H., Hoffrén, R., Hylander, K., Jiménez-Alfaro, B., Jucker, T., Klinges, D., Kolstela, J., Kopecký, M., Kovács, B., Maeda, E.E., Máliš, F., Man, M., Mathiak, C., Meineri, E., Naujokaitis-Lewis, I., Nijs, I., Normand, S., Nuñez, M., Orczewska, A., Peña-Aguilera, P., Pincebourde, S., Plichta, R., Quick, S., Renault, D., Ricci, L., Rissanen, T., Segura-Hernández, L., Selvi, F., Serra-Diaz, J.M., Soifer, L., Spicher, F., Svenning, J.-C., Tamian, A., Thomaes, A., Thoonen, M., Trew, B., Van de Vondel, S., van den Brink, L., Vangansbeke, P., Verdonck, S., Vitkova, M., Vives-Ingla, M., von Schmalensee, L., Wang, R., Wild, J., Williamson, J., Zellweger, F., Zhou, X., Zuza, E.J., De Frenne, P., 2024. Microclimate, an important part of ecology and biogeography. Global Ecology and Biogeography n/a, e13834. https://doi.org/10.1111/geb.13834
3. Bellamy, D.J., Bridgewater, P., Marshall, C., Tickle, W.M., 1969. Status of the Teesdale Rarities. Nature 222, 238–243. https://doi.org/10.1038/222238a0
4. Maclean, I.M.D., Early, R., 2023. Macroclimate data overestimate range shifts of plants in response to climate change. Nat. Clim. Chang. 1–7. https://doi.org/10.1038/s41558-023-01650-3
5. Suggitt, A.J., Wilson, R.J., Isaac, N.J.B., Beale, C.M., Auffret, A.G., August, T., Bennie, J.J., Crick, H.Q.P., Duffield, S., Fox, R., Hopkins, J.J., Macgregor, N.A., Morecroft, M.D., Walker, K.J., Maclean, I.M.D., 2018. Extinction risk from climate change is reduced by microclimatic buffering. Nature Climate Change 1. https://doi.org/10.1038/s41558-018-0231-9
6. Simpson, E.G., Pearse, W.D., 2021. Fractal triads efficiently sample ecological diversity and processes across spatial scales. Oikos 130, 2136–2147. https://doi.org/10.1111/oik.08272
7. Klinges, D.H., Lembrechts, J.J., Van de Vondel, S., Greenlee, E.J., Hayles-Cotton, K., Senior, R.A., 2025. A workflow for microclimate sensor networks: Integrating geographic tools, statistics, and local knowledge. Ecological Informatics 91, 103376. https://doi.org/10.1016/j.ecoinf.2025.103376