Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics
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Mitigating ammonium and nitrate leaching in rice-wheat crop rotation: efficacy of neem coated urea and compost co-application
Get PDF•Introduction: Leaching losses of applied N are an indirect source of nitrous oxide (N2O) emission, a major greenhouse gas emitted from fertilized soils. Mineral nitrogen (N) leaching research has largely concentrated on nitrate (NO3−), while ammonium (NH4+) leaching remains understudied. The cultivation conditions for rice and wheat are distinctly different, impacting the leaching losses of both NH4+ and NO3−.
•Methods: This study investigated the influence of different N treatments, i.e., no-N control, neem coated urea (NCU-N 100%; 120 kgN ha-1), 60 kgN ha-1 Neem coated urea +30 kgN ha-1 compost (75% N); 90 kgN ha-1 Neem coated urea +30 kgN ha-1 compost (100% N) and 120 kgN ha-1 Neem coated urea +30 kgN ha-1 compost (125% N) in comparison with prilled urea (PU, 120 kgN ha-1). Compost was applied @ 2.6 tonnes ha-1 to all integrated treatments to provide 30 kgN ha-1.
•Results and discussion: The peak concentration of soil NH4+ and NO3− was delayed by two-three days in NCU and integrated NCU + compost compared to PU in both rice and wheat, due to the slow-release effect of neem oil coating in NCU. In rice, the percolation rate of water was almost half than in wheat soil. The mineral N leaching loss in rice ranged from 0.4 to 4.6 kg NH4+-N ha-1 and 0.46–5.12 kg NO3-N ha-1 during the 2 years. In an annual rice-wheat cycle, the total N leaching loss was 6.2%–7.0% of the applied N fertilizer. The total mineral N loss was higher in PU than NCU by 7.8% and 10% in rice and wheat, respectively. Substitution of 25% of mineral N with compost decreased the total N leaching by 14.8% and 10.3% in rice and wheat, respectively, compared to NCU (100%). The crop N uptake increased significantly (p<0.05) with NCU and integrated NCU + compost (100%) over PU. Application of 125%-N significantly increased the total mineral N leaching. The total mineral-N leaching loss was 15.9% higher in rice than wheat across the different treatments. The integrated N application, combining 75% NCU and 25% compost, can reduce mineral-N leaching, improve nitrogen uptake and maintain economic yields in rice-wheat cropping system
Solar farms as potential future refuges for bumblebees
Get PDFSolar farms offer an opportunity for habitat creation for wildlife, including insect pollinators, potentially simultaneously contributing to both low‐carbon energy and nature recovery. However, it is unknown whether cobenefits would persist under future land‐use change given that habitat value is context dependent. For the 1042 operational solar farms in Great Britain, we predict their ability to support bumblebee populations (both inside and outside the solar farm) under three different socioeconomic futures. These futures represent alternative 1 km scale landcover projections for the year 2050 with accompanying narratives. We downscale these to 10 m resolution, spatially allocating crop rotations, agri‐environment interventions and other habitat features consistent with the scenario narratives, to realistically represent fine‐scale landscape elements of relevance to bumblebee populations. We then input these detailed maps into a sophisticated process‐based model that simulates bumblebee foraging and population dynamics, enabling us to predict bumblebee density in and around Great Britain's solar farms, accounting for the effects of their changed habitat context and configuration in these different future scenarios. We isolate the drivers of bumblebee density change across scenarios and scales and show that solar farm management was the main driver of bumblebee density within solar farms, with ~120% higher densities inside florally enhanced compared to turf grass solar farms, although the exact figure was influenced by wider landcover changes. In foraging zones immediately surrounding solar farms, landscape changes had a greater impact on bumblebee densities, suggesting a single solar farm in isolation generally did not counteract the influence of wider land‐use changes expected under future scenarios. In addition to providing insights into the potential future value of pollinator habitat on solar farms, our methodology demonstrates how combining process‐based modelling with landcover projections that are downscaled to ecologically relevant resolutions can be used to better assess future effectiveness of habitat interventions. This represents a step change in our ability to account for species' interactions with socioeconomically driven futures, which can be extended and applied to other taxa and land‐use interventions
Online workshop on hydrological forecasting: training needs and opportunities
Get PDFReport on "Online Workshop on Hydrological Forecasting: Training Needs and Opportunities", held on 2 September 2025. This workshop was organised by UK Centre for Ecology & Hydrology and West African Science Service Centre on Climate Change and Adapted Land Use, under the NC for Global Challenges Programme
Distal cryptotephra records in the Falkland Islands refine South American tephrochronology
Get PDFCryptotephra (non-visible volcanic ash) deposits in the Falkland Islands (Islas Malvinas) provide a distal record of South American volcanism and ash dispersal into the South Atlantic Ocean. Here, we present three new cryptotephra records from peatlands in the archipelago and use these data to refine the age estimates of key regional tephra isochrons. Major-minor-trace element glass geochemistry and high-resolution radiocarbon chronologies were used to correlate cryptotephra deposits with known explosive eruptions at Reclus volcano (R1), Monte Burney and Hudson volcano (H2). We also identify cryptotephra deposits likely originating from Chaitén volcano, the Antillanca volcanic complex and two Mid Holocene eruptions of Aguilera volcano. Careful examination of major-minor element data from tephras linked with Monte Burney MB1 demonstrates discrepancies between medial and distal deposits preserved in Patagonia, Laguna Potrok Aike and the Falkland Islands. These suggest that two Early Holocene tephra deposits from Monte Burney may be widely distributed. Our integrated Bayesian age-depth model refines the median ages of Hudson H2 (4230–3775 calibrated years before present; cal yr BP), deposits from Monte Burney (as viewed from the Falkland Islands, 9540-9455 cal yr BP) and Reclus volcano R1 (14,800-14,060 cal yr BP). We also propose that the age of Aguilera A1 is older than previously suggested and dates to 4390-4150 cal yr BP. Our expanded geochemical dataset of volcanic glasses and new age constraints for these isochrons aid distal and near source tephra correlations and complement the current tephrochronological framework of the region
The role of Antarctic sea ice in the Earth system: Perspectives informed by 130,000 years of sea ice records [preprint]
No full textAntarctic sea-ice cover reached historically low levels in 2023, consistent with the simulated decrease in sea-ice extent in response to anthropogenic warming. Antarctic sea ice is closely linked to multiple components of the Earth system, thus its demise could precipitate widespread, cascading changes across the cryosphere, atmosphere, and ocean. However, the nature and strength of these interconnections are poorly understood, and they are often inadequately represented in models. In this review paper we use modern observations, models and paleoclimate archives covering the last glacial cycle to gain insights into how reductions in sea ice may affect other components of the Earth system. We review how Antarctic sea ice interacts with ocean and atmosphere circulation, ice sheets and ice shelves, marine productivity, and the carbon cycle over the last glacial cycle, for which we have the most robust sea-ice reconstructions. The review finds strong evidence from theory and models for impacts of Antarctic sea ice on the Earth system. Paleo-proxy reconstructions provide examples where changes in sea ice co-occur with changes in the carbon cycle, marine productivity, and ocean circulation. However, challenges remain in isolating the impact of sea ice in a highly interconnected system
Hydrological summary for the United Kingdom: July 2025
Get PDFThe monthly summary of hydrological conditions in the United Kingdom is compiled as part of the National Hydrological Monitoring Programme (a joint UKCEH and BGS enterprise). The report features contemporary data for rainfall, river flow, reservoir and groundwater levels in the form of maps and graphs. A commentary is provided on the status of the nation’s water resources and any notable hydrological events during the month. The National River Flow and National Groundwater Level Archives help provide an historical context for these contemporary assessments. Financial support for the production of the Hydrological Summaries is provided by Defra, the Environment Agency, the Scottish Environment Protection Agency, the Rivers Agency in Northern Ireland and the Office of Water Services
Evolution of dayside chorus into nightside plasmaspheric hiss
Get PDFPlasmaspheric hiss is an incoherent, broadband, whistler-mode emission that is found primarily in the Earth’s dense plasmasphere and is believed to be largely responsible for the formation of the slot region between the inner and outer radiation belts. Beginning with the earliest observations of plasmaspheric hiss in the 1970s, it was noticed that duskside hiss emissions tended to disappear during the main phase of geomagnetic storms, and reappear again during the recovery phase. Here, we perform extensive ray tracing in a realistic, three-dimensional cold plasma density model that evolves during the course of a storm. On the basis of these simulations, we show that the formation of a broad, dayside plasmaspheric plume during the main phase of the storm prevents access of dayside chorus rays to the plasmaspheric dusk-midnight region, which explains the observed disappearance of plasmaspheric hiss waves in this region. In the recovery phase of the storm, however, the narrow, rotated plume and eroded plasmasphere create the ideal conditions for dayside chorus rays to propagate into the plasmasphere, attain a large azimuthal propagation component, and ‘hop’ over the narrow plume, thus enabling them to access the dusk-midnight region and explaining the observed reappearance of duskside hiss waves in the storm recovery phase
Transformations in exposure to debris flows in post-earthquake Sichuan, China
Get PDFPost-earthquake debris flows can exceed volumes of 1 × 106 m3 and pose significant challenges to downslope recovery zones. These stochastic hazards form when intense rain remobilises coseismic landslide material. As communities recover from earthquakes, they mitigate the effects of these debris flows through modifications to catchments such as building check dams and levees. We investigate how different catchment interventions change the exposure and hazard of post-2008 debris flows in three gullies in the Sichuan Province, China. These were selected based on the number of post-earthquake check dams – Cutou (two), Chediguan (two), and Xiaojia (none). Using high-resolution satellite images, we developed a multitemporal building inventory from 2005 to 2019, comparing it to the spatial distribution of previous debris flows and future modelled events. Post-earthquake urban development in Cutou and Chediguan increased exposure to a major debris flow in 2019, with inundation impacting 40 % and 7 % of surveyed structures respectively. We simulated future debris flow runouts using LAHARZ to investigate the role of check dams in mitigating three flow volumes – 104 m3 (low), 105 m3 (high), and 106 m3 (extreme). Our simulations show check dams effectively mitigate exposure to low- and high-flow events but prove ineffective for extreme events, with 59 % of buildings in Cutou, 22 % in Chediguan, and 33 % in Xiaojia significantly affected. We verified our analyses by employing a statistical exposure model, adapted from a social vulnerability equation. Cutou's exposure increased by 64 % in 2019 and Chediguan's by 52 %, while Xiaojia's increased by only 2 % in 2011, highlighting that extensive grey infrastructure correlates with higher exposure to extreme debris flows but less so with smaller events. Our work suggests that the presence of check dams contributes to a perceived reduction in downstream exposure. However, this perception can lead to a levee effect, whereby exposure to larger, less frequent events is ultimately increased
Visions and plausible pathways for positive lake futures in the English Lake District, UK: report on the introductory PLURALAKES workshop in the Lake District National Park, UK. 20th May 2025.
Get PDF•This report details the discussions and narratives which emerged following an introductory workshop in the English Lake District National Park carried out by the PLURALAKES project team on the 20th of May 2025. A local graphic illustrator Bethan Thorsby, Sporadic illustration joined the day to capture the discussions.
•The PLURALAKES project seeks to improve the health of lake ecosystems, by including the multiple values and perspectives involved in lake ecosystem management, moving towards shared future visions for the lakes and the pathways on how to reach them.
This workshop was the first in a series, centred on activities and discussions supported by two frameworks: (1) the Nature Futures Framework and (2) the X-curve. The Nature Futures Framework (NFF) is a tool to guide exploration of the diverse values people hold towards nature and test and develop scenarios which incorporate these values and future visions. The X-curve is a tool used to support discussions on navigating the pathways or changes to these futures. At the start of the day, attendees were asked to share memories or their connections to a lake or lakes in the Lake District National Park. Following an introduction to the NFF, participants identified where within the framework their values most aligned resulting in three groups, associated with different values with nature. Discussion sessions on visioning positive lake futures, describing “seeds of change” or examples of positive practice and navigating tensions were then conducted, with notes and illustrations capturing the dialogue of the three groups. This report describes these discussions in more detail.
•Shared visions for positive lake futures included values of respect, responsibility and connection with restored shoreline and standing water habitats and increased diversity and abundance of lake species. However, as visions and pathways were further explored it became clear that tensions exist between two sets of the Nature Futures Framework values. The first, ‘nature for nature’, focusses on valuing nature for its own sake and having space for nature to function naturally in a way that increases resilience to pressure. The second, ‘nature for society’, emphasizes the importance of increasing human integration and activity, to promote connection and allow society to continue to utilise the resources and services needed from nature. It brought into question how, where and when can nature exist in the absence of human influence in a region such as the Lake District National Park which seeks to promote a prosperous economy, world class visitor experiences and vibrant communities, whilst sustaining its ecosystems (see Lake District National Park - The Lake District Foundation - Charity of the Lake District).
•Continued dialogue and investigation of pathways to the future using different scenarios for change will help to identify where compromise is most needed. Exploring these pathways and scenarios of change will form the next steps planned in the PLURALAKES project. Finally, it should be recognised that some important local voices were missing from the workshop, despite efforts to engage with these groups, including landowners, tourist, recreational and agricultural representatives, meaning a full diversity of perspectives are not included in these findings. The PLURALAKES team will continue to try and engage with members from these sectors/communities in future workshops
Trusted Research Environment: architecture and implementation, a case study
Get PDFThis report summarises a theoretical examination of the use of a Trusted Research Environment (TRE) for integrating static and dynamic environmental data sets. This work was funded through the UKRI Digital Research Infrastructure BOOST and AMPLIFY projects.
The project proposal was predicated that an environmental TRE would be implemented by the University of Manchester hosted Digital Solution infrastructure. For technical reasons beyond the scope of this report, this has not been implemented within the timescale of the AMPLIFY project.
Therefore, this report summarises the conceptual thinking for how a TRE might be implemented for a use case of provision of confidential water resource data. This requirement crosscuts data supplied by BGS, from the National Geoscience Data Centre (NGDC) and integrates it in combination with data supplied from a hypothetical and confidential water industry data source, and also a conceptual data source provided by an environmental regulator (such as the Environmental Agency for England or Scottish Environmental Protection Agency).
The project objective is to provide an understanding of how a hypothetical model incorporating both geospatial and sensor driven modelling data sources could be implemented within a specimen TRE to demonstrate how this could be developed from both an architecture and modelling standpoint
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