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The UK sixth carbon budget has recommended domestic biomass supply should increase to meet growing demand, planting a minimum of 30,000 hectares of perennial energy crops a year by 2035, with a view to establishing 700,000 hectares by 2050 to meet the requirements of the balanced net zero pathway. Miscanthus is a key biomass crop to scale up domestic biomass production in the United Kingdom. A cohesive land management strategy, based on robust evidence, will be required to ensure upscaling of miscanthus cultivation maximizes the environmental and economic benefits and minimizes undesirable consequences. This review examines research into available land areas, environmental impacts, barriers to uptake, and the challenges, benefits, and trade‐offs required to upscale miscanthus production on arable land and grassland in the United Kingdom. Expansion of perennial biomass crops has been considered best restricted to marginal land, less suited to food production. The review identifies a trade‐off between avoiding competition with food production and a risk of encroaching on areas containing high‐biodiversity or high‐carbon stocks, such as semi‐natural grasslands. If areas of land suitable for food production are needed to produce the biomass required for emission reduction, the review indicates there are multiple strategies for miscanthus to complement long‐term food security rather than compete with it. On arable land, a miscanthus rotation with a cycle length of 10–20 years can be employed as fallow period for fields experiencing yield decline, soil fatigue, or persistent weed problems. On improved grassland areas, miscanthus presents an option for diversification, flood mitigation, and water quality improvement. Strategies need to be developed to integrate miscanthus into farming systems in a way that is profitable, sensitive to local demand, climate, and geography, and complements rather than competes with food production by increasing overall farm profitability and resilience. [ABSTRACT FROM AUTHOR]

Presents information on a study wherein the number of density of neutral ground state barium atoms desorbed from an operating dispenser cathode was measured using intracavity laser absorption spectroscopy. Methods; Results; Discussion.

Discusses a study conducted on oxygen-doped, semi-insulating layers of (aluminum-gallium) indium phosphide grown on gallium arsenide using organometallic vapor phase epitaxy. Effect of oxygen doping on semi-insulating layers of the substance; Secondary-ion mass spectrometry measurements; Measured concentration of oxygen in the layers of the substance in samples used in the study.

In this present study the ability of the SimSphere Soil Vegetation Atmosphere Transfer (SVAT) model in estimating key parameters characterising land surface interactions was evaluated. Specifically, SimSphere's performance in predicting Net Radiation (Rnet), Latent Heat (LE), Sensible Heat (H) and Air Temperature (Tair) at 1.3 and 50m was examined. Model simulations were validated by ground-based measurements of the corresponding parameters for a total of 70 days of the year 2011 from 7 CarboEurope network sites. These included a variety of biomes, environmental and climatic conditions in the models evaluation. Overall, model performance can largely be described as satisfactory for most of the experimental sites and evaluated parameters. For all model parameters compared, predicted H fluxes consistently obtained the highest agreement to the in-situ data in all ecosystems, with an average RMSD of 55.36Wm-2. LE fluxes and Rnet also agreed well with the in-situ data with RSMDs of 62.75 and 64.65Wm-2 respectively. A good agreement between modelled and measured LE and H fluxes was found, especially for smoothed daily flux trends. For both Tair 1.3m and Tair 50m a mean RMSD of 4.14 and 3.54 °C was reported respectively. This work presents the first all-inclusive evaluation of SimSphere, particularly so in a European setting. Results of this study contribute decisively towards obtaining a bet ter understanding of the model's structure and its correspondence to the real world system. Findings also further establish the model's capability as a useful teaching and research tool in modelling Earth's land surface interactions. This is of considerable importance in the light of the rapidly expanding use of the model worldwide, including ongoing research by various Space Agencies examining its synergistic use with Earth Observation data towards the development of operational products at a global scale. [ABSTRACT FROM AUTHOR]

Unintentionally doped layers of (AlxGa1-x)y In1-y P with energy gaps of approximately 2.0 eV were grown lattice matched to GaAs by organometallic vapor phase epitaxy. These layers were high resistivity. Current-voltage (I-V) and capacitance-voltage (C-V) measurements were made on Cr/Au (AlxGa1-x)y In1-y P-GaAs metal-insulator-semiconductor capacitors. These measurements gave a ln I variation with V1/2 as observed for insulators such as Si3N4 on Si. This conduction behavior is characteristic of the Frenkel–Poole effect which is the electric field enhanced thermal excitation of trapped electrons into the conduction band. The C-V measurements were similar to the small hysteresis behavior of high-resistivity oxygen-doped AlxGa1-xAs on GaAs. [ABSTRACT FROM AUTHOR]

Growing Miscanthus species and hybrids has received strong scientific and commercial support, with the majority of the carbon (C) modelling predictions having focused on the high-yield, sterile and noninvasive hybrid Miscanthus × giganteus. However, the potential of other species with contrasting phenotypic and physiological traits has been seldom explored. To better understand the mechanisms underlying C allocation dynamics in these bioenergy crops, we pulse-labelled ( 13 CO 2 ) intact plant-soil systems of Miscanthus × giganteus (GIG), Miscanthus sinensis (SIN) and Miscanthus lutarioriparius (LUT) and regularly analysed soil respiration, leaves, stems, rhizomes, roots and soils for up to 190 days until leaf senescence. A rapid isotopic enrichment of all three species was observed after 4 h, with the amount of 13 C fixed into plant biomass being inversely related to their respective standing biomass prior to pulse-labelling (i.e., GIG < SIN < LUT). However, both GIG and LUT allocated more photoassimilates in the aboveground biomass (leaves+stems = 78 % and 74 %, respectively) than SIN, which transferred 30% of fixed 13 C in its belowground biomass (rhizomes+roots). Although less fixed 13 C was recovered from the soils (<1 %), both rhizospheric and bulk soils were signficantly more enriched under SIN and LUT than under GIG. Importantly, the soils under SIN emitted less CO 2 , which suggests it could be the best choice for reaching C neutrality. These results from this unique large-scale study indicate that careful species selection may hold the success for reaching net GHG mitigation., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: N.P. McNamara, D.M.O. Elias reports financial support was provided by Natural Environment Research Council. K. Farrar, I. Donninson reports financial support was provided by Biotechnology and Biological Sciences Research Council., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Afforestation and reforestation to meet 'Net Zero' emissions targets are considered a necessary policy by many countries. Their potential benefits are usually assessed through forest carbon and growth models. The implementation of vegetation demography gives scope to represent forest management and other size-dependent processes within land surface models (LSMs). In this paper, we evaluate the impact of including management within an LSM that represents demography, using both in-situ and reanalysis climate drivers at a mature, upland Sitka spruce plantation in Northumberland, UK. We compare historical simulations with fixed and variable CO 2 concentrations, and with and without tree thinning implemented. Simulations are evaluated against the observed vegetation structure and carbon fluxes. Including thinning and the impact of increasing CO 2 concentration ('CO 2 fertilisation') gave more realistic estimates of stand-structure and physical characteristics. Historical CO 2 fertilisation had a noticeable effect on the Gross Primary Productivity seasonal-diurnal cycle and contributed to approximately 7% higher stand biomass by 2018. The net effect of both processes resulted in a decrease of tree density and biomass, but an increase in tree height and leaf area index., (© 2023. Springer Nature Limited.)

Demand for sustainably produced biomass is expected to increase with the need to provide renewable commodities, improve resource security and reduce greenhouse gas emissions in line with COP26 commitments. Studies have demonstrated additional environmental benefits of using perennial biomass crops (PBCs), when produced appropriately, as a feedstock for the growing bioeconomy, including utilisation for bioenergy (with or without carbon capture and storage). PBCs can potentially contribute to Common Agricultural Policy (CAP) (2023-27) objectives provided they are carefully integrated into farming systems and landscapes. Despite significant research and development (R&D) investment over decades in herbaceous and coppiced woody PBCs, deployment has largely stagnated due to social, economic and policy uncertainties. This paper identifies the challenges in creating policies that are acceptable to all actors. Development will need to be informed by measurement, reporting and verification (MRV) of greenhouse gas emissions reductions and other environmental, economic and social metrics. It discusses interlinked issues that must be considered in the expansion of PBC production: (i) available land; (ii) yield potential; (iii) integration into farming systems; (iv) R&D requirements; (v) utilisation options; and (vi) market systems and the socio-economic environment. It makes policy recommendations that would enable greater PBC deployment: (1) incentivise farmers and land managers through specific policy measures, including carbon pricing, to allocate their less productive and less profitable land for uses which deliver demonstrable greenhouse gas reductions; (2) enable greenhouse gas mitigation markets to develop and offer secure contracts for commercial developers of verifiable low-carbon bioenergy and bioproducts; (3) support innovation in biomass utilisation value chains; and (4) continue long-term, strategic R&D and education for positive environmental, economic and social sustainability impacts., Competing Interests: The authors declare that progress reported in this paper, which includes input from industrial partners, is not biased by their business interests., (© 2023 The Authors. GCB Bioenergy Published by John Wiley & Sons Ltd.)

While existing moratoria in Indonesia and Malaysia should preclude continued large-scale expansion of palm oil production into new areas of South-East Asian tropical peatland, existing plantations in the region remain a globally significant source of atmospheric carbon due to drainage driven decomposition of peatland soils. Previous studies have made clear the direct link between drainage depth and peat carbon decomposition and significant reductions in the emission rate of CO 2 can be made by raising water tables nearer to the soil surface. However, the impact of such changes on palm fruit yield is not well understood and will be a critical consideration for plantation managers. Here we take advantage of very high frequency, long-term monitoring of canopy-scale carbon exchange at a mature oil palm plantation in Malaysian Borneo to investigate the relationship between drainage level and photosynthetic uptake and consider the confounding effects of light quality and atmospheric vapour pressure deficit. Canopy modelling from our dataset demonstrated that palms were exerting significantly greater stomatal control at deeper water table depths (WTD) and the optimum WTD for photosynthesis was found to be between 0.3 and 0.4 m below the soil surface. Raising WTD to this level, from the industry typical drainage level of 0.6 m, could increase photosynthetic uptake by 3.6 % and reduce soil surface emission of CO 2 by 11 %. Our study site further showed that despite being poorly drained compared to other planting blocks at the same plantation, monthly fruit bunch yield was, on average, 14 % greater. While these results are encouraging, and at least suggest that raising WTD closer to the soil surface to reduce emissions is unlikely to produce significant yield penalties, our results are limited to a single study site and more work is urgently needed to confirm these results at other plantations., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The research was carried out as part of a project funded by the Malaysian Palm Oil Board (MPOB). Lip Khoon Kho and Elisa Rumpang are both employees of MPOB. The research was carried out with the support of Sarawak Oil Palm Berhad (SOPB) on whose land the research project was based., (Copyright © 2022. Published by Elsevier B.V.)

Need for regional economic development and global demand for agro-industrial commodities have resulted in large-scale conversion of forested landscapes to industrial agriculture across South East Asia. However, net emissions of CO 2 from tropical peatland conversions may be significant and remain poorly quantified, resulting in controversy around the magnitude of carbon release following conversion. Here we present long-term, whole ecosystem monitoring of carbon exchange from two oil palm plantations on converted tropical peat swamp forest. Our sites compare a newly converted oil palm plantation (OPnew) to a mature oil palm plantation (OPmature) and combine them in the context of existing emission factors. Mean annual net emission (NEE) of CO 2 measured at OPnew during the conversion period (137.8 Mg CO 2  ha -1  year -1 ) was an order of magnitude lower during the measurement period at OPmature (17.5 Mg CO 2  ha -1  year -1 ). However, mean water table depth (WTD) was shallower (0.26 m) than a typical drainage target of 0.6 m suggesting our emissions may be a conservative estimate for mature plantations, mean WTD at OPnew was more typical at 0.54 m. Reductions in net emissions were primarily driven by increasing biomass accumulation into highly productive palms. Further analysis suggested annual peat carbon losses of 24.9 Mg CO 2 -C ha -1  year -1 over the first 6 years, lower than previous estimates for this early period from subsidence studies, losses reduced to 12.8 Mg CO 2 -C ha -1  year -1 in the later, mature phase. Despite reductions in NEE and carbon loss over time, the system remained a large net source of carbon to the atmosphere after 12 years with the remaining 8 years of a typical plantation's rotation unlikely to recoup losses. These results emphasize the need for effective protection of tropical peatlands globally and strengthening of legislative enforcement where moratoria on peatland conversion already exist., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

The recent expansion of oil palm (OP, Elaeis guineensis) plantations into tropical forest peatlands has resulted in ecosystem carbon emissions. However, estimates of net carbon flux from biomass changes require accurate estimates of the above ground biomass (AGB) accumulation rate of OP on peat. We quantify the AGB stocks of an OP plantation on drained peat in Malaysia from 3 to 12 years after planting using destructive harvests supported by non-destructive surveys of a further 902 palms. Peat specific allometric equations for palm (R 2  = 0.92) and frond biomass are developed and contrasted to existing allometries for OP on mineral soils. Allometries are used to upscale AGB estimates to the plantation block-level. Aboveground biomass stocks on peat accumulated at ~6.39 ± 1.12 Mg ha -1 per year in the first 12 years after planting, increasing to ~7.99 ± 0.95 Mg ha -1 yr -1 when a 'perfect' plantation was modelled. High inter-palm and inter-block AGB variability was observed in mature classes as a result of variations in palm leaning and mortality. Validation of the allometries defined and expansion of non-destructive inventories across alternative plantations and age classes on peat would further strengthen our understanding of peat OP AGB accumulation rates.

Background: Many older adults live with serious illness for years before their death. Nurse-led primary palliative care could improve their quality of life and ability to stay in their community., Objectives: To assess feasibility and acceptability of a nurse-led Transitional Palliative Care (TPC) program for older adults with serious illness., Methods: The study was a pilot trial of the TPC program in which registered nurses assisted patients with symptom management, communication with care providers, and advance care planning. Forty-one older adults with chronic conditions were enrolled in TPC or standard care groups. Feasibility was assessed through enrollment and attrition rates and degree of intervention execution. Acceptability was assessed through surveys and exit interviews with participants and intervention nurses., Results: Enrollment rate for those approached was 68%, and completion rate for those enrolled was 71%. The TPC group found the intervention acceptable and helpful and was more satisfied with care received than the control group. However, one-third of participants perceived that TPC was more than they needed, despite the number of symptoms they experienced and the burdensomeness of their symptoms. More than half of the participants had little to no difficulty participating in daily activities., Conclusion: This study demonstrated that the nurse-led TPC program is feasible, acceptable, and perceived as helpful. However, further refinement is needed in selection criteria to identify the population who would most benefit from primary palliative care before future test of the efficacy of this intervention.

Growth in planted areas of Miscanthus for biomass in Europe has stagnated since 2010 due to technical challenges, economic barriers and environmental concerns. These limitations need to be overcome before biomass production from Miscanthus can expand to several million hectares. In this paper, we consider the economic and environmental effects of introducing seed based hybrids as an alternative to clonal M. x giganteus ( Mxg ). The impact of seed based propagation and novel agronomy was compared with current Mxg cultivation and used in 10 commercially relevant, field scale experiments planted between 2012 and 2014 in the United Kingdom, Germany, and Ukraine. Economic and greenhouse gas (GHG) emissions costs were quantified for the following production chain: propagation, establishment, harvest, transportation, storage, and fuel preparation (excluding soil carbon changes). The production and utilization efficiency of seed and rhizome propagation were compared. Results show that new hybrid seed propagation significantly reduces establishment cost to below £900 ha -1 . Calculated GHG emission costs for the seeds established via plugs, though relatively small, was higher than rhizomes because fossil fuels were assumed to heat glasshouses for raising seedling plugs (5.3 and 1.5 kg CO 2 eq. C Mg [dry matter (DM)] -1 ), respectively. Plastic mulch film reduced establishment time, improving crop economics. The breakeven yield was calculated to be 6 Mg DM ha -1 y -1 , which is about half average United Kingdom yield for Mxg ; with newer seeded hybrids reaching 16 Mg DM ha -1 in second year United Kingdom trials. These combined improvements will significantly increase crop profitability. The trade-offs between costs of production for the preparation of different feedstock formats show that bales are the best option for direct firing with the lowest transport costs (£0.04 Mg -1 km -1 ) and easy on-farm storage. However, if pelleted fuel is required then chip harvesting is more economic. We show how current seed based propagation methods can increase the rate at which Miscanthus can be scaled up; ∼×100 those of current rhizome propagation. These rapid ramp rates for biomass production are required to deliver a scalable and economic Miscanthus biomass fuel whose GHG emissions are ∼1/20th those of natural gas per unit of heat.

The scalar Huygens-Fresnel principle is reformulated to take into account the vector nature of light and its associated directed electric and magnetic fields. Based on Maxwell's equations, a vector Huygens secondary source is developed in terms of the fundamental radiating units of electromagnetism: the electric and magnetic dipoles. The formulation is in terms of the vector potential from which the fields are derived uniquely. Vector wave propagation and diffraction formulated in this way are entirely consistent with Huygens's principle. The theory is applicable to apertures larger than a wavelength situated in dark, perfectly absorbing screens and for points of observation in the right half-space at distances greater than a wavelength beyond the aperture. Alternatively, a formulation in terms of the fields is also developed; it is referred to as a vector Huygens-Fresnel theory. The proposed method permits the determination of the diffracted electromagnetic fields along with the detected irradiance.