The incidences of respiratory allergies are at an all-time high. Pollen aeroallergens can reflect changing climate, with recent studies in Europe showing some, but not all, pollen types are increasing in severity, season duration and experiencing an earlier onset. This study aimed to identify pollen trends in the UK over the last twenty-six years for a range of pollen sites, with a focus on the key pollen types of Poaceae (grass), Betula (birch) and Quercus (oak) and to examine the relationship of these trends with meteorological factors. Betula pollen seasons show no significant trends for onset, first high day or duration but increasing pollen production in the Midlands region of the UK is being driven by warmer temperatures in the previous June and July. Quercus pollen seasons are starting earlier, due to increasing temperature and sunshine totals in April, but are not becoming more severe. The seasons are lasting longer, although no significant climate drivers for this were identified. The first high day of the Poaceae pollen season is occurring earlier in central UK regions due to an increasing trend for all temperature variables in the previous December, January, April, May and June. Severity and duration of the season show no significant trends and are spatially and temporally variable. Important changes are occurring in the UK pollen seasons that will impact on the health of respiratory allergy sufferers, with more severe Betula pollen seasons and longer Quercus pollen seasons. Most of the changes identified were caused by climate drivers of increasing temperature and sunshine total. However, Poaceae pollen seasons are neither becoming more severe nor longer. The reasons for this included a lack of change in some monthly meteorological variables, or land-use change, such as grassland being replaced by urban areas or woodland.

Phases of rapid climate change throughout the early to mid Holocene coincide with regional human population expansion in Scotland and North-West Europe. Palaeoenvironmental signals of climate and anthropogenically driven vegetation changes can therefore be difficult to separate. To identify whether it is possible to distinguish potential signatures of anthropogenic clearance and agricultural activities from climatic drivers of landscape change in the early to mid Holocene in the region, two topographically contrasting sites on the Isle of Skye and the Isle of Bute were investigated. A multiproxy approach including pollen, spore, microcharcoal, loss on ignition and particle size analyses was adopted to investigate changes in vegetation and climate. There are subtle indications that the 8200 cal BP climate event had an effect on the vegetation composition at both sites. Signals of anthropogenic woodland clearance are apparent early in the sequence at Peat Hill (Bute), indicated by a peak in Poaceae (grass) cereal-type (7–14%) at 8592–8793 cal BP, alongside a decrease in arboreal pollen, which could not be associated with a regional episode of climate change. Early to mid Holocene vegetation changes at Lyndale House (Skye) occur alongside regional changes in precipitation and sea level and therefore cannot be readily separated. Continuous declines in arboreal pollen from ca. 5000 cal BP at Lyndale House indicates the onset of widespread clearance on Skye via felling and sustained grazing pressures.

Grass pollen is the world’s most harmful outdoor aeroallergen and sensitivity varies between species. Different species of grass flower at different times, but it is not known how airborne communities of grass pollen change in time and space. Persistence and high mobility of grass pollen could result in increasingly diverse seasonal pollen communities. Conversely, if grass pollen does not persist for an extended time in the air, shifting pollen communities would be predicted throughout the summer months. Here, using targeted high throughput sequencing, we tracked the seasonal progression of airborne Poaceae pollen biodiversity across Britain, throughout the grass allergy season. All grass genera displayed discrete, temporally restricted peaks of pollen incidence which varied with latitude, revealing that the taxonomic composition of grass pollen exposure changes substantially across the allergy season. By developing more refined aeroallergen profiling, we predict that our findings will facilitate the exploration of links between taxon-specific exposure of harmful grass pollen and disease, with concomitant socio-economic benefits.

This research investigated the impact of The Churchill Barriers on the coastal and marine environment through analysis of nearshore and terrestrial cores using geochemical and diatom analyses, ²¹⁰Pb and ¹³⁷Cs dating and field surveying. Analyses of a core taken from near barrier 1 showed that an eutrophic environment dominated throughout the sedimentary sequence. An increase in calcium carbonate, combined with increases in strontium and sodium and a small change in diatom composition, is thought to relate to barrier construction around 1940–1945. A similar pattern is revealed from a core taken near barrier 4 and also from Echna Loch (Burray). On the east side of barrier 4, a large area of sand deposition has occurred as a result of the sheltered environment offered by the barrier. Sediment has been transported northwards by longshore drift and moved onshore from offshore sand bars, forming an extensive sand dune environment. The sediment deposition can be seen to a lesser extent on the east side of the barriers 1, 2 and 3. These results suggest tentatively that barrier formation may have impacted on water flow patterns, and hence algal communities, leading to changes in floral composition. Furthermore, changes in sediment patterns, coastal geomorphology are evident from barrier emplacement.