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Identifying a cell wall ideotype for increased soil carbon contents associated with Miscanthus cultivation.
Full text linkDedicated biomass crops are widely accepted as an important part of decarbonising economies. Miscanthus is a leading dedicated biomass crop that embodies high yield with many co-benefits including soil carbon sequestration plus the benefits of perennial agronomy. Breeding programmes for Miscanthus are in their infancy but it is apposite to consider the potential for breeding improved soil carbon sequestration. We focussed on gross biomass inputs from leaf, roots and rhizome and examined both dry weight and cell wall composition as key factors that influence soil carbon sequestration. We measured lignin, cellulose, hemicellulose, carbon and nitrogen from all three tissues in different Miscanthus genotypes that had been grown in field plots and compared for soil carbon. There was a significant genotypic effect on most compositional traits from all three tissue types and composition also varied between tissue types. When combined with soil C data from field grown plants, lignin and lignin:N were shown to be useful predictive factors (along with soil depth) for total soil organic C and this combination of factors explained 86% of the model variance for Miscanthus derived soil C. Examples of trade-offs were observed but a high sequestering plant includes low root lignin and high belowground biomas
Valorisation of spent mushroom substrate by secondary microbial fermentation
Full text linkGlobal mushroom production exceeds 45 million tonnes, involving growth on a lignocellulosic substrate. More than 70% of these mushrooms are considered wild mushrooms that are grown on a lignocellulose substrate. At the end of the growth cycle, the remaining spent mushroom substrate (SMS) is considered waste with little value and is often discarded. The limited information available on the fibre content remaining in SMS indicates that different white-rot fungi can result in significant differences in the hemicellulose and lignin content, which in turn may impact the second fermentation step. Secondary fermentation has found uses in the production of biofuels, as a preserved ruminant feed, for enzyme production, in the formation of microbial compounds, and as an amended fertiliser. Finally, achieving secondary fermentation of SMS could involve the development and use of larger-scale solid-state fermentation. This review article has shown that research into secondary fermentation of SMS has been a relatively new field occurring over the past 14 years. Graphical abstract
Refining the timing of Middle Pleistocene ( MIS 12 to MIS 6) ice advances into northern central Europe:Sedimentological analysis and single‐grain luminescence dating of glaciotectonic complexes and tunnel‐valley fills
No full textThe timing of the Middle Pleistocene ice advances into northern central Europe is still disputed. In this study, we summarize the current state of knowledge on the age of the Middle Pleistocene Saalian and Elsterian ice advances into northern central Europe and provide new single‐grain luminescence ages of related meltwater deposits. Twenty‐five samples for luminescence dating were taken from five different Saalian ice‐marginal positions and (upthrusted) Elsterian tunnel‐valley fills in northern Germany. The sampled Elsterian deposits mainly comprise subaqueous fan and delta sediments, which were deposited in glacial lakes that formed in underfilled tunnel valleys and their marginal areas. The estimated luminescence ages range between >578 and 346±98 ka, probably correlating with Marine Isotope Stage (MIS) 12, although an older and/or younger age (MIS >14 to MIS 8) cannot be excluded. During MIS 6, four different ice advances are recorded from the study area. During the maximum extent of the first and second Saalian Drenthe ice advances, large ice‐dammed lakes formed along the Fennoscandian ice sheets, which catastrophically drained during ice‐margin retreat. Further north, glaciofluvial fans and/or larger glaciofluvial distributive systems formed along the ice sheets. The first Saalian Drenthe ice advance probably occurred during MIS 6e‐d. However, the estimated luminescence ages range between 293±59 and 209±37 ka, and therefore, we cannot rule out an earlier Saalian pre‐Drenthe ice advance into the north‐eastern part of the study area. After a phase of ice‐sheet retreat, fluvial erosion and soil formation, the second Saalian Drenthe ice advance probably occurred during late MIS 6c. The estimated luminescence ages range between 172±38 and 123±18 ka. Meltwater deposits that are related to the third Saalian Drenthe (Hondsrug ice stream) and/or Warthe ice advances have luminescence ages of 128±19 to 123±22 ka, correlating with MIS 6b‐a. The glaciotectonic complexes partly have a multiphase development related to the different Saalian ice advances. Smaller composite ridge systems with shallow detachments (20–60 m deep) evolved in areas with tunnel‐valley fills, probably controlled by the rheological contrasts between sandy meltwater deposits and underlying fine‐grained deposits of the uppermost Elsterian tunnel‐valley fills (Lauenburg Clay Complex). In contrast, larger glaciotectonic complexes with deep detachments (>100 m deep) formed further south (‘Rehburg line’) where large tunnel valleys are absent
DINOv3-Driven Semantic Segmentation for Landslide Mapping in Mountainous Regions
No full textLandslide hazard assessment increasingly demands the joint analysis of heterogeneous remote sensing data; however, automating this process remains difficult due to the pronounced resolution and texture discrepancies existing between satellite and aerial sensors. To address these limitations, this study proposes a robust segmentation framework capable of extracting sensor-robust representations. The framework leverages a DINOv3 transformer encoder and exploits representations from multiple transformer layers to capture complementary visual information, ranging from fine-grained surface textures to global semantic contexts, overcoming the receptive field constraints of conventional CNNs. Experiments on the Longxi satellite dataset achieve a Dice coefficient of 0.96 and an IoU of 0.938, and experiments on the Longxi UAV dataset achieve a Dice coefficient of 0.965 and an IoU of 0.941. These results show consistent segmentation performance on both the Longxi satellite and UAV datasets, despite differences in spatial resolution and surface appearance between acquisition platforms
Drought Response in Miscanthus:Breeding Increases Radiation and Water Use Efficiency Over Three Contrasting Years in Central Germany
No full textMore and new sources of biomass are needed for renewable energy and renewable products for the bioeconomy. A leading new source of biomass is the highly sustainable perennial grass crop Miscanthus. The majority of the Miscanthus crop comprises a clone of Miscanthus × giganteus (M × g) of limited genetic variation and poor yield under dry growth conditions. The parental species of M × g, M. sacchariflorus and M. sinensis , are distributed over a large geographical range in Eastern Asia and may be used to improve on M × g. From breeding trials, we selected seven novel hybrids and two control genotypes including M × g. We grew these in a field experiment on drought‐prone soil in Germany with and without irrigation. To identify superior Miscanthus types, we estimated radiation use efficiency (RUE), yield and water use efficiency (WUE) from within‐season measurements made over three contrasting growing seasons. Temporal variations in RUE and WUE for different genotypes varied significantly and two novel hybrids, WAT6 and WAT8, achieved the highest yields. To achieve goodness of fit to yield measurements, genotype‐specific parameters for process descriptions in the model MiscanFor were adjusted for the two superior genotypes. These parameters included earlier shooting and an increased threshold of overheating. When the model was run over ten years, despite generating the highest yield values, WAT8 accumulated less biomass than WAT6 over the longer term. The response of WUE to variation in soil capillary pressure and vapour pressure deficit was examined. WUE of M × g increased with the severity of water stress then declined again. The superior yielding genotypes were more able to sustain biomass accumulation and/or water use under the highest stress. We believe that combining physiology with crop modelling is a powerful way to inform genetic and agronomic improvements needed to secure the future supply of biomass for the bioeconomy
FarmLCA:A novel approach to assess agroecological innovations in Life Cycle Assessment
No full textContext: Agroecological innovations are seen as solutions to reduce environmental impacts of agriculture but can potentially lead to trade-offs with food production. Appropriate tools are needed to better understand synergies and trade-offs among environmental issues, resource efficiency and food production.Objective: This study presents the FarmLCA tool, which models farms as interconnected crop-livestock systems and assesses environmental impacts from farms and farm-inputs. A mixed beef farm serves as case study to assess synergies and trade-offs of avoiding human edible feed in beef production.Methods: FarmLCA allows the calculation of cradle-to-farm gate life cycle assessments (LCA). Emissions of environmentally harmful substances from crops and livestock are modelled based on the farm management. Upstream impacts from imported inputs (including fertilizer or feed) are accounted for with life cycle inventory data. Yields and nutrient requirements are checked for plausibility, based on management handbooks, while manure availability and composition are calculated based on livestock production. Environmental impacts, nutrient use efficiency and food production for a typical mixed beef farm in Scotland were calculated (baseline) and compared to alternative farm management scenarios: a Feed-no-Food scenario, avoiding concentrate feeds resulting in a smaller herd size and a circular Feed-no-Food scenario, additionally optimizing productivity and synergies between crop and livestock (e.g. more legumes in crop rotation, reduced replacement rate and feed waste).Results and conclusions: In the Feed-no-Food scenario, the beef production was reduced by 25 %, but more calories and protein were produced overall due to cereal and legumes now being available for direct human consumption. However, slower growth of livestock led to increased environmental impact of beef, whilst reduced livestock numbers required more mineral fertilizer for crop production to replace on-farm manure. In the circular Feed-noFood scenario, beef and overall calorie production were slightly reduced compared to the baseline, but 1.5 more high quality protein (expressed by the Digestible Indispensable Amino Acid Score, DIAAS), were produced. Environmental impacts of beef were reduced and nitrogen self-sufficiency improved due to increased legume share in the rotation.Significance: Existing LCA approaches often fail to capture the complex dynamics of integrated crop-livestock systems and agroecological practices. FarmLCA addresses this by modelling both on-farm processes and up-stream inputs, enabling a consistent assessment of environmental impacts, nutrient use efficiency, and food production. It offers a more holistic and systemic view of the consequences of agroecological innovations and enables the identification of synergies and trade-offs between environmental protection, resource efficiency, and food production
Refining Late Holocene explosive eruption histories of the Main Ethiopian Rift with lake sediment tephra records
No full textThe Main Ethiopian Rift (MER) hosts a rapidly growing population exposed to eruption hazards from ∼60 active Holocene volcanoes. The geological record preserves significant information about the nature and frequency of past explosive volcanism in the rift, but the Holocene eruption record remains incomplete and its implications for contemporary volcanic hazards are yet to be fully understood. Here we use lake sediments preserved at four sites: Babogaya (MER), Haro Kori and Wergoba (southeastern Ethiopian plateau), and Dendi (western Ethiopian plateau) to constrain the Late Holocene tephrostratigraphic record. We focus on Lake Babogaya in the Bishoftu Volcanic Field which preserves 5 visible and 2 cryptotephra layers dating between 0.4 and 4.5 ka. Distal ash in this record is chemically correlated by major element composition to at least three eruptions of the Boset Volcanic Complex and two eruptions of the Corbetti Volcanic System in the last 5 ka, providing the first absolute age control for recent explosive activity of Boset. Ashfall originating from the 1.3–1.9 ka VEI 5 Wendo Koshe Younger Pumice eruption of Corbetti is identified in three records allowing re-estimation of total erupted volume for this event with improved distal constraints. The total erupted volume is >1.3 times larger than previous estimates, dispersing ∼4.0 km3 (2.75–6.75 km3) of tephra over ∼90,000 km2, and predicts ashfall within range of Addis Ababa. An additional visible tephra preserved at Haro Kori, dating to 2.3 ka BP, indicates another large-magnitude eruption of Corbetti occurred within the last 2.5 ka. These findings demonstrate the value of distal lake records for improving the regional eruption record of the MER, providing crucial controls on the timing and magnitude of recent rift volcanism. Ash dispersal from central rift volcanism is capable of inundating populous areas across central Ethiopia; our work supports more informed preparation for future volcanic ash hazards in a region undergoing rapid development.</p
A place-based assessment of biodiversity intactness in sub-Saharan Africa
No full textMaintaining biodiversity is central to the sustainable development agenda1. However, a lack of context-specific biodiversity information at policy-relevant scales has posed major limitations to decision-makers2,3. To address this challenge, we undertook a comprehensive assessment of the biodiversity intactness of sub-Saharan Africa4 using place-based knowledge of 200 African biodiversity experts5. We estimate that the region has on average lost 24% of its pre-colonial and pre-industrial faunal and floral population abundances, ranging from losses of <20% for disturbance-adapted herbaceous plants to 80% for some large mammals. Rwanda and Nigeria are the least intact (<55%), whereas Namibia and Botswana are the most intact (>85%). Notably, most remaining organisms occur in unprotected, relatively untransformed rangelands and natural forests. Losses in biodiversity intactness in the worst-affected biomes are driven by land transformation into cropland in grasslands and fynbos (Mediterranean-type ecosystems), by non-agricultural degradation in forests and by a combination of the two drivers in savannas. This assessment provides decision-makers with multifaceted, contextually appropriate and policy-relevant information on the state of biodiversity in an understudied region of the world. Our approach could be used in other regions, including better-studied localities, to integrate contextual, place-based knowledge into multiscale assessments of biodiversity status and impacts.</p
Nonthermal Pressures:Key to Energy Balance and Structure Formation near Sgr A* in the Milky Way
No full textThe circumnuclear region of the Galactic center offers a unique laboratory to study energy balance and structure formation around Sgr A⋆. This work investigates thermal and nonthermal processes within a 7 pc distance from Sgr A⋆. Using MeerKAT 1.3 GHz radio continuum data and Atacama Large Millimeter/submillimeter Array H40α radio recombination line emission from the ACES survey, we separate free–free and synchrotron components at ∼0.2 pc resolution. With a thermal fraction of ≃13%, the 1.3 GHz emission shows tight correlations with the Herschel PACS IR data. The correlation between the equipartition magnetic field and molecular gas traced by JCMT 12CO (J = 3 → 2) observations reveals a balance between the magnetic field, cosmic rays, and molecular gas pressures south of the circumnuclear disk on ∼0.7 pc scales. Unlike the magnetic field and ionized gas, the molecular gas density declines in the cavity (R ≤ 2 pc) toward the center, likely due to feedback from Sgr A⋆. We find that nonthermal pressure from turbulent gas nearly balances magnetic and cosmic-ray pressures and exceeds the thermal pressure by 2 orders of magnitude. The medium surrounding Sgr A⋆ is filled by a low-β (thermal-to-magnetic energy ratio), supersonic plasma, with an Alfvén Mach number ≃ 4 (assuming equipartition). Analysis of the mass-to-magnetic flux ratio suggests that the circumnuclear region is mostly subcritical and, therefore, the magnetic field can help stabilize gas clouds against gravitational collapse
Uniformity of heating across sample holders during luminescence measurements
No full textFor luminescence research, samples are often heated prior to and/or during measurement to measure the thermoluminescence (TL) signal or to remove charge from shallow traps. The reproducibility and repeatability of luminescence measurements will be influenced by how consistently and uniformly the samples are heated, both within a single aliquot and between different readers or sample positions. While the effects of temperature lag during heating have been intensively studied, the spatial uniformity of temperature across samples has received less attention. This study presents spatially-resolved measurements of the temperature of the heating strip, a steel cup and an aluminium single grain disc in a Risø TL/OSL DA20 reader. Temperature is calculated using black body emissions from the three materials, detected with an Electron Multiplying Charge Coupled Device (EMCCD). The results show that temperature is not spatially uniform across any of the three materials, although the degree of variation differs between them. The largest temperature variation is observed across the steel cup (∼18 % at a temperature of 500 °C), followed by the heating strip (∼8 % at a temperature of 500 °C), and then the single grain disc (∼2 % at a temperature of 250 °C). The steel cup also has greater anisotropy in temperature compared to the single grain disc. This study suggests that spatial variation in temperature can be minimised by using sample holders made of materials with high thermal conductivity (e.g. aluminium or silver), and that the impact of thermal variation can be reduced by restricting samples to the central portion of a sample holder (e.g. the central 2 mm of a sample holder (i.e. ‘small aliquots’)).</p