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Item A continuous feast of bramble: Rubus fruticosus agg. is a key cross‐seasonal dietary resource for a fallow deer population(John Wiley & Sons, Inc., 2025-02-09) Gresham, Amy; Pillay, Kirthana; Healey, John R.; Eichhorn, Markus P.; Ellison, Amy M.; Lowe, Abigail; Cordes, Line S.; Creer, Simon; Shannon, Graeme; Natural Environment Research Council; Wales Biodiversity Partnership; European Regional Development FundContext: Deer (Cervidae) populations are increasing in many global regions, leading to concerns about their impacts on temperate forests. Advancing evidence-based management requires a detailed understanding of the dietary habits of deer and how these are shaped by resource availability. Methodology: We studied the diet of fallow deer (Dama dama) in North Wales (United Kingdom), using faecal DNA metabarcoding. Samples were collected monthly from three woodlands during 2019–2021. Tree surveys and seasonal ground flora surveys were conducted in these woodlands and seven additional woodlands. Preference analyses were used to assess the consumption of plant taxa relative to their availability. Results: The fallow deer consumed high proportions of bramble (Rubus fruticosus agg.) across the seasons, especially in the winter months. Diet diversity was significantly lower in winter compared to the other seasons, suggesting that the deer were bulk foraging on a widely available, predictable resource to conserve energy during winter. Grasses did not form a major component of the diet in any season. The preference analysis showed that spatially clustered woody taxa (e.g. Betula sp., Corylus sp. and Fraxinus sp.) occurred less often than expected in the diet, while widespread woody species occurred in the diet more often than expected (e.g. Rosa sp., Prunus sp. and Quercus sp.). Practical implication: The expansion of deer populations in the United Kingdom has occurred alongside the recovery and maturation of degraded or planted forests since the middle of the 20th century. Despite reduced light availability in these closed-canopy forests and increased herbivory pressure, bramble has remained a dominant understory plant compared to other less herbivory-tolerant plant species. Perhaps as a consequence, bramble has become the winter survival resource for this fallow deer population, remaining a prominent dietary component throughout the year. With increasing disturbance from extreme weather and tree diseases leading to a more open canopy structure, bramble cover is set to increase in European forests, which could support further expansion of deer populations. As we work to expand tree cover and enhance forest resilience and biodiversity, we should seek to understand the dynamic interactions of increasing deer populations with rapidly changing treescapes.Item The effect of seasonality on the foraging behaviour and breeding success of a tropical marine top predator(Elsevier Ltd., 2025-01-17) Saldanha, Sarah; Militão, Teresa; Cox, Sam L.; Llamas-Cano, Irene; Dinis, Herculano Andrade; Gomes, Ivandra S. G. C.; Lopes, Artur; dos Santos, Maldini; Brito, Vania; Hernández-Montero, Marcos; González-Solís, Jacob; MAVA Foundation; Ministerio de Economía, Comercio y Empresa; Ministerio de Ciencia e Innovación; British Ornithologists' Union; Generalitat de CatalunyaIn polar and temperate regions seasonality in environmental conditions is an important driver of animal phenology. In tropical systems, where the environment is relatively homogeneous year-round, the link between phenology and seasonality is weakened, and many species breed asynchronously or even year-round. This leads to the question of how these species adapt to seasonal changes, which remain present albeit to a lesser extent. To assess relationships between foraging plasticity and seasonal changes in oceanographic conditions and resource availability, we investigated the foraging ecology of the red-billed tropicbird (Phaethon aethereus), a poorly studied pantropical species that breeds year-round in Cabo Verde. From 2017 to 2022, we monitored tropicbird nests at three islands (Boavista, Sal and the Cima Islet) and GPS tracked 907 foraging trips from 329 adults to evaluate seasonality in nest occupancy, foraging patterns and efficiency, chick growth, chick and adult body condition, and breeding success, alongside links to seasonal changes in resource availability and environmental conditions. We found seasonal patterns in foraging behaviour, with individuals taking more distant and less sinuous foraging trips, using a larger core foraging area, spending more time foraging during twilight, and consuming more squid in the dry season (December-June), than in the wet season (July-November). Moreover, nest occupancy, chick body condition and breeding success were higher in the dry season. We suggest that the observed seasonal patterns are related to an increase in the availability of squid at the end of the dry season, and a decrease in the nest-site suitability and an increase in weather-related foraging costs in the wet season. Our results provide some of the first in-depth knowledge on the seasonal variation in foraging behaviour of a tropical seabird species, suggesting seasonality in tropical systems may be a stronger driver of the movements of top predators than previously thought.Item Acidogenic fermentation of Ulva in a fed-batch reactor system: tubular versus foliose biomass(Elsevier Ltd., 2025-01-08) Lawrence, James; Oliva, Armando; Murphy, Jerry D.; Lens, Piet N. L.; Science Foundatin IrelandThe present study proposes a biorefinery of the macroalgae Ulva, focusing on evaluating two different morphologies of the species (foliose and tubular) during acidogenic fermentation in fed-batch reactors. Stage 1 of the study evaluates lyophilised foliose and tubular Ulva, whilst Stage 2 analyses the impact of ulvan extraction on volatile fatty acids yield and changes in carbohydrate availability. Acetic, propionic, and butyric acids were produced from each substrate, with peak concentrations of total VFAs recorded at 2179.5 mg HAc/L (foliose Ulva) and 2029.3 mg HAc/L (tubular Ulva) when ulvan was present. After ulvan extraction, the acidogenic fermentation of the foliose morphotype was negatively affected, reaching at most 315.3 mg HAc/L. In contrast, the extraction showed no influence on the tubular morphotype, peaking at 2165.0 mg HAc/L. Additional variations were noted in the availability of carbohydrates in each substrate during the acidogenic fermentation process. The ulvan-extracted tubular morphotype exhibited the highest peak in carbohydrate concentration (9.8 g glucose/L), whilst the ulvan-extracted foliose morphotype yielded up to 8.5 g glucose/L. This study highlights the biorefinery potential of Ulva biomass, proposing a multiple cascading approach linking multiple energy and biomolecule applications to maximise the valorisation of the biomass.Item A low-carbon electricity transition for small island developing states: The case of Mauritius(Elsevier Ltd., 2024-12-20) Jaggeshar, Doorgeshwaree; Mao, Xianqiang; Guo, Zhi; Zusman, Eric; Tu, Kevin; Chen, Xing; Ma, Zhiyuan; Global Energy Interconnection GroupA clean energy transition can not only help rebuild the energy landscape of small island developing states (SIDS) but also boost their resilience and long-term development prospects. This study employs the Open-Source Energy Modeling System (OSeMOSYS) model to analyze low-carbon transition pathways for Mauritius, which are aligned with its nationally determined contribution (NDC) objectives to increase renewable energy to 60 % and phase out coal by 2030. The study applied key performance indicators to assess this pathway against energy self-sufficiency, economic, environmental and social criteria. The study showed that renewable energy sources, namely, solar, biomass, wind and waste-to-energy, can be game-changers for the island. The optimal transition pathway would achieve a renewable target of 76.8 % and reduce CO2 emissions by more than 67 % across the modeling period at an estimated cost of 1.94 billion USD by 2040. Finally, the study evaluated the implications of Mauritius' clean transition in terms of its effects on green jobs as well as whether there is sufficient infrastructure, administrative and financial capacity and energy pricing policies to support the optimal pathway. The study concludes that the experience modeling a low-carbon transition pathway for Mauritius could also offer useful lessons for other SIDS contemplating similar transitions.Item Rapid and high-precision cavity-enhanced spectroscopic measurement of HONO and NO2: Application to emissions from heavy-duty diesel vehicles in chassis dynamometer tests and in mobile monitoring(Elsevier B.V., 2025-12-16) Wang, Meng; Liu, Wenyang; Ding, Xiang; Liu, Tao; Zhou, Wenxin; Lou, Shengrong; Venables, Dean S.; Varma, Ravi; Huang, Cheng; Chen, Jun; National Natural Science Foundation of China; National Key Research and Development Program of China; Science Foundation IrelandNitrous acid (HONO) is crucial in atmospheric chemistry as it is a major precursor for hydroxyl radicals (OH), the dominant atmospheric oxidant. Hydroxyl radicals are essential in the formation of secondary air pollutants like ozone and particulate matter. This study presents a newly developed Incoherent Broadband Cavity Enhanced Absorption Spectroscopy (IBBCEAS) system for precise and rapid measurements of HONO and nitrogen dioxide (NO2) emissions. The instrument's optical cavity (formed by two mirrors separated by 96 cm and with reflectivity of 0.99955 at 378 nm) resulted in an effective optical path length of 1.4 km. With an integration time of 5 s, the 1σ measurement precisions for HONO and NO2 were 0.19 ppb and 0.48 ppb with overall measurement uncertainties of 10 % and 7 %, respectively. Comparative analysis of the IBBCEAS and a commercial cavity-attenuated phase shift (CAPS) systems under non-emission conditions demonstrated excellent agreement (slope = 1.01 and R2 = 0.98). The instrument was applied to study HONO and NO2 emissions from heavy-duty vehicles in chassis dynamometer tests and mobile monitoring. Chassis dynamometer tests revealed that HONO and NO2 emissions depend strongly on vehicle speed and driving conditions. We find a HONO/NOX ratio of 1.01 × 10−2 across the entire China-World Transient Vehicle Cycle (C-WTVC) driving cycle. Mobile monitoring in urban areas shows emission characteristics similar to those observed in chassis dynamometer tests. Frequent acceleration-deceleration patterns of diesel vehicles under congested traffic conditions lead to higher HONO and NO2 emissions compared to driving under steady speed conditions. Improving traffic flow conditions will help reduce HONO and NO2 emissions.