Mountain birch genetics and recovery in Scotland

About the Project

This project will investigate the genetic diversity and adaptive potential of mountain birch to inform upland restoration in Scotland, collaborating with both industry and conservation stakeholders.

Montane woodlands in Scotland have undergone extensive decline and fragmentation, in part due to historical land use, such as overgrazing. Remaining populations are small and isolated, increasing vulnerability to stochastic events and inbreeding. Despite this, these habitats are of high conservation value, supporting biodiversity, slope stabilisation and flood mitigation.

Mountain birch, primarily downy birch (Betula pubescens), now persists in scattered upland populations across Scotland, often alongside dwarf birch (Betula nana) and hybrids. This fragmented distribution contrasts with more continuous distributions elsewhere in Europe, raising questions about its historical extent in Scotland. Hybridisation and morphological variation complicate identification, although cytometry will enable reliable differentiation between species.

Genetic diversity is key to resilience and adaptation yet remains poorly understood in Scottish upland birch. Observed variation in morphology and phenology across environmental gradients may reflect genetic adaptation or phenotypic plasticity, but to what extent remains unknown. Addressing these knowledge gaps is critical for restoration, particularly in guiding seed sourcing strategies and supporting recovery montane woodland ecosystems.

Research questions

• Are there genetic and morphological differences between higher and lower altitude populations?
• What is the state of genetic diversity within and between populations in Scotland? How does this compare to other European mountain birch populations?
• How much adaptive diversity is present and how is it distributed within and between populations?
• What is the role of environmental and ecological drivers in determining population differences in adaptive variation?

Methods

Focusing primarily on downy birch (Betula pubescens), the study will utilise field assessments, reciprocal transplant trials and genetic analyses.

• Genetic analysis – morphological and genetic variation will be assessed between populations along an altitudinal gradient. Flow cytometry will distinguish B. pubescens, B. nana, and hybrids. Neutral genetic variation (e.g. microsatellites or SNPs) will be used to quantify diversity, population structure, gene flow, and inbreeding.
• Reciprocal transplant trials – a recently established reciprocal transplant trial (high and low altitude trial sites), including seed collected from populations along an altitudinal gradient, will be assessed for traits such as growth and phenology to test local adaptation and phenotypic plasticity.
• Environmental and spatial analysis – fine-scale mapping of species and hybrids will be linked to environmental variables (e.g. climate, soils, topography, vegetation). Tissue sampling, cytometry, and genotyping will be combined with assessments of reproduction (seed production and viability) to evaluate how environmental and ecological factors shape population structure.

Supervisors

Core team: Prof. Alistair Jump (University of Stirling), Dr. Alastair Skeffington (University of Stirling) and Dr. Tom Sim (Forest Research).

Wider team: Dr. Joan Cottrell (Forest Research), Sarah Watts (Corrour Estate), Dr. Shaila Rao (National Trust for Scotland), Dr. Stephen Cavers (UKCEH) and Dr. Aline Finger (Royal Botanic Garden Edinburgh).

Training and skills

The successful candidate will benefit from access to state-of-the-art laboratory facilities and collaborate with industry and conservation stakeholders. The student will receive project-specific training including cytometry, DNA extraction and molecular genotyping, assessment of adaptive traits and ecological site assessment. Training will also be provided in the analysis of molecular, ecological and adaptive trait data and in scientific writing. The successful candidate would further benefit from a wide range of researcher development opportunities and support at the University of Stirling.

Entry Requirements

We are looking for a motivated and enthusiastic graduate with a strong background in a relevant discipline, e.g. ecology, evolutionary biology, plant sciences, forestry, environmental science, conservation biology, genetics, or a related field. A relevant MSc and/or significant experience in molecular laboratory work, ecological fieldwork, data analysis and scientific writing/publication is highly desirable.

You will need to hold a full driving license.

How to apply

To apply, please send a CV along with a covering letter setting out your motivation, experience and suitability for the PhD to a.s.jump@stir.ac.uk and thomas.sim@forestresearch.gov.uk, including the project title in your email subject line.