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Bioenergy with Carbon Capture and Storage (BECCS) features heavily in the energy scenarios designed to meet the Paris Agreement targets, but the models used to generate these scenarios do not address environmental and social implications of BECCS at the regional scale. We integrate ecosystem service values into a land-use optimization tool to determine the favourability of six potential UK locations for a 500 MW BECCS power plant operating on local biomass resources. Annually, each BECCS plant requires 2.33 Mt of biomass and generates 2.99 Mt CO2 of negative emissions and 3.72 TWh of electricity. We make three important discoveries: (a) the impacts of BECCS on ecosystem services are spatially discrete, with the most favourable locations for UK BECCS identified at Drax and Easington, where net annual welfare values (from the basket of ecosystems services quantified) of £39 and £25 million were generated, respectively, with notably lower annual welfare values at Barrow (-£6 million) and Thames (£2 million); (b) larger BECCS deployment beyond 500 MW reduces net social welfare values, with a 1 GW BECCS plant at Drax generating a net annual welfare value of £19 million (a 50% decline compared with the 500 MW deployment), and a welfare loss at all other sites; (c) BECCS can be deployed to generate net welfare gains, but trade-offs and co-benefits between ecosystem services are highly site and context specific, and these landscape-scale, sitespecific impacts should be central to future BECCS policy developments. For the United Kingdom, meeting the Paris Agreement targets through reliance on BECCS requires over 1 GW at each of the six locations considered here and is likely, therefore, to result in a significant welfare loss. This implies that an increased number of smaller BECCS deployments will be needed to ensure a win-win for energy, negative emissions and ecosystem services. [ABSTRACT FROM AUTHOR]

We present the first assessment of the impact of land use change ( LUC) to second-generation (2G) bioenergy crops on ecosystem services ( ES) resolved spatially for Great Britain ( GB). A systematic approach was used to assess available evidence on the impacts of LUC from arable, semi-improved grassland or woodland/forest, to 2G bioenergy crops, for which a quantitative 'threat matrix' was developed. The threat matrix was used to estimate potential impacts of transitions to either Miscanthus, short-rotation coppice ( SRC, willow and poplar) or short-rotation forestry ( SRF). The ES effects were found to be largely dependent on previous land uses rather than the choice of 2G crop when assessing the technical potential of available biomass with a transition from arable crops resulting in the most positive effect on ES. Combining these data with constraint masks and available land for SRC and Miscanthus ( SRF omitted from this stage due to lack of data), south-west and north-west England were identified as areas where Miscanthus and SRC could be grown, respectively, with favourable combinations of economic viability, carbon sequestration, high yield and positive ES benefits. This study also suggests that not all prospective planting of Miscanthus and SRC can be allocated to agricultural land class (ALC) ALC 3 and ALC 4 and suitable areas of ALC 5 are only minimally available. Beneficial impacts were found on 146 583 and 71 890 ha when planting Miscanthus or SRC, respectively, under baseline planting conditions rising to 293 247 and 91 318 ha, respectively, under 2020 planting scenarios. The results provide an insight into the interplay between land availability, original land uses, bioenergy crop type and yield in determining overall positive or negative impacts of bioenergy cropping on ecosystems services and go some way towards developing a framework for quantifying wider ES impacts of this important LUC. [ABSTRACT FROM AUTHOR]

The paper estimates the potential contribution of Miscanthus × giganteus (Miscanthus) and short rotation coppice (SRC; in Great Britain often willow and poplar species, e.g. Salix. viminalis L. x S. viminalis var Joruun) to the heat and electricity needs in Great Britain to 2050 under climate change, using a model system which is composed of a partial equilibrium model and two process-based terrestrial biogeochemistry models. If the whole available area of land suitable for Miscanthus and SRC of 8 Mha is considered, results show that the contribution of Miscanthus and SRC to the heat and electricity supply would be significant. Under the projected climate and an imposed energy policy to 2050, the potential contribution would range from 139, 291 GWh to 230, 605 GWh for heat and from 112, 481 GWh to 127, 868 GWh for electricity by 2050. This would provide over 60 % of total heat and electricity needs in Great Britain. Using realistic implementation scenarios on just 0.4 Mha of land, Miscanthus and SRC could still contribute more than 5 % of heat and electricity needs in Great Britain. We conclude that Miscanthus and SRC have the potential to form part of a diverse renewable energy portfolio for Great Britain. In addition to climate and energy policy, the contribution of Miscanthus and SRC to heat and electricity will be impacted by the efficiency of combined heat and power (CHP) and alternative energy crops, and the area of land eventually used for dedicated bioenergy crops. [ABSTRACT FROM AUTHOR]

Process and empirical-based models that describe lignocellulosic biomass yield of the perennial energy grass Miscanthus (MiscanFor©), short rotation coppice ( SRC) trees and shrubs, poplar and willow (ForestGrowth- SRC) and a number of short rotation forest trees ( ESC- CARBINE), were used to estimate the yield potential for current and future climates across Great Britain ( GB). In current climates, modelled yields for all feedstock crops varied between 8.1 and 10.6 Mg dry weight ( DW) ha−1 yr−1 with willow SRC and poplar SRF producing the lowest and highest yields respectively. For the medium emissions scenario ( UKCP09) in 2050, mean yield for all feedstock crops varied between 7.6 and 12.7 Mg DW ha−1 yr−1 with willow SRC and poplar SRF once again the lowest and the highest recorded yields. There were clear geographical trends within GB. Miscanthus yield was higher than all others in the south-west (13.1 Mg DW ha−1 yr−1), SRC willow and SRC poplar in the north-west (12.1-15.8 Mg DW ha−1 yr−1) and in the midlands and south-east, SRF poplar was the highest yielding (10.5-11.6 Mg DW ha−1 yr−1). These geographical trends changed little with climate out to 2050, with mean yield of each 'best feedstock' increasing from 12.7 to 14.2 Mg DW ha−1 yr−1. Out to 2050, SRC declined slightly and Miscanthus and SRF poplar increased as the 'best feedstock' option. Except for a few localized examples, only SRF poplar had a higher yield than SRC or Miscanthus. These data suggest that in current and future climates, lignocellulosic biomass plantation species can be selected and optimized for best yield performance in different regions of GB. This modelling framework provides a valuable starting-point for which to test the performance of new genetic material, as this becomes available and parameterized for the models and socio-economic scenarios that may impact on the bioenergy industry. [ABSTRACT FROM AUTHOR]

The paper presents a model system, which consists of a partial equilibrium model and process-based terrestrial biogeochemistry models, to determine the optimal distributions of both Miscanthus ( Miscanthus × giganteus) and short rotation coppice willow ( SRC) ( Salix. viminalis L. x S. viminalis var Joruun) in Great Britain ( GB), as well as their potential contribution to meet heat and electricity demand in GB. Results show that the potential contribution of Miscanthus and SRC to heat and electricity demand is significant. Without considering farm-scale economic constraints, Miscanthus and SRC could generate, in an economically competitive way compared with other energy generation costs, 224 800 GWh yr−1 heat and 112 500 GWh yr−1 electricity, with 8 Mha of available land under Miscanthus and SRC, accounting for 66% of total heat demand and 62% of total electricity demand respectively. Given the pattern of heat and electricity demand, and the relative yields of Miscanthus and SRC in different parts of GB, Miscanthus is mainly favoured in the Midlands and areas in the South of GB, whereas SRC is favoured in Scotland, the Midlands and areas in the South of GB. [ABSTRACT FROM AUTHOR]

To achieve the UK Government's aim of expansion in the growth of perennial energy crops requires farmers to select these crops in preference to conventional rotations. Existing studies estimating the total potential resource have either only simplistically considered the farmer decision-making and opportunity costs, for example using an estimate of annual land rental charge; or have not considered spatial variability, for example using representative farm types. This paper attempts to apply a farm-scale modelling approach with spatially specific data to improve understanding of potential perennial energy crop supply. The model main inputs are yield maps for the perennial energy crops, Miscanthus and willow grown as short-rotation coppice ( SRC), and regional yields for conventional crops. These are used to configure location specific farm-scale models, which optimize for profit maximization with risk aversion. Areas that are unsuitable or unavailable for energy crops, due to environmental or social factors, are constrained from selection. The results are maps of economic supply, assuming a homogenous farm-gate price, allowing supply cost curves for the UK market to be derived. The results show a high degree of regional variation in supply, with different patterns for each energy crop. Using estimates of yields under climate change scenarios suggests that Miscanthus supply may increase under future climates while the opposite effect is suggested for SRC willow. The results suggest that SRC willow is only likely to able to supply a small proportion of the anticipated perennial energy crop target, without increases in market prices. Miscanthus appears to have greater scope for supply, and its dominance may be amplified over time by the effects of climate change. Finally, the relationship to the demand side of the market is discussed, and work is proposed to investigate the factors impacting how the market as a whole may develop. [ABSTRACT FROM AUTHOR]

• Limited information on likely supply and spatial yield of bioenergy crops exists for the UK. Here, productivities are reported of poplar ( Populus spp.) and willow ( Salix spp.) grown as short-rotation coppice (SRC), using data from a large 49-site yield trial network. • A partial least-squares regression technique was used to upscale actual field trial observations across England and Wales. Spatial productivity was then assessed under different land-use scenarios. • Mean modelled yields ranged between 4.9 and 10.7 oven-dry tonnes (odt) ha−1 yr−1. Yields were generally higher in willow than in poplar, reflecting the susceptibility of older poplar genotypes to rust and their tendency for single stem dominance. Replacing 10% of arable land, 20% of improved grassland and 100% of set-aside grassland in England and Wales with the three most productive genotypes would yield 13 Modt of biomass annually (supplying 7% of UK electricity production or 48% of UK combined heat and power (CHP) production). • Results show existing SRC genotypes have the immediate potential to be an important component of a mixed portfolio of renewables and that, in future, as new and improved genotypes become available, higher yields could extend this potential further. [ABSTRACT FROM AUTHOR]

Transplants of beech, Fagus sylvatica, L. were planted in 1 m plastic tubes containing a mixture of peat and grit and sunk into the ground inside open-top chambers at a site in southern Britain. Chambers were ventilated with either charcoal-filtered or unfiltered air and water was withheld from half of the trees within each chamber. The influence of air quality on the growth and development of roots and interactions between air quality and drought were investigated. During May and June 1988 the growth of fine (diameter < 1.5 mm) and large roots (diameter > 15 m) was not significantly altered by air quality. A destructive harvest conducted in July revealed that trees exposed to ambient pollution had significantly longer roots (P < 0.05) compared with trees grown in filtered air, despite slightly less root dry weight (not statistically significant). Specific root length (SRL, root length per unit root dry weight) was also significantly larger (P < 0.05) for trees grown in the unfiltered chambers and exposed to pollution, suggesting a root system which was not only longer but also consisted of thinner roots, compared with the roots of trees grown in clean air. The effects of pollution were more pronounced for roots in the lower half of the 1 m profile. During August 1988, water was withheld from half of the trees within each chamber. Well-watered trees exposed to unfiltered air had significantly less root dry weight (P < 0.05) compared with well-watered trees grown in filtered air, although root length and SRL were both greater for trees grown in unfiltered air compared with those grown in filtered air. Again the effects were more pronounced lower in the root profile. Withholding water resulted in less root length being produced irrespective of air quality treatment, suggesting that trees exposed to pollution would not necessarily be more susceptible to drought-stress. [ABSTRACT FROM AUTHOR]

Transplants of beech (Figus sylvatica L.) were grown in open-top chambers ventilated with either charcoal-filtered or unfiltered air. From May until September measurements of stomatal conductance to water vapour (g.) were made on trees in the chambers. On six out of seven occasions, leaves which had expanded during the first Hush (initial shoot extension, during May) in unfiltered air, had lower stomatal conductances, compared with those grown in filtered air; this was significant on three occasions (P < 0.05). Leaves which expanded later in the season (second flush or lammas growth) responded differently to the air quality treatments, with greater stomatal conductances recorded for trees exposed to unfiltered air. Measurements of leaf (psychrometry) and shoot (pressure bomb) water relations indicated that air quality had little effect on turgor pressure (P). Values of solute (φs) and water (φw) potential were higher for trees grown in unfiltered air. Trees were transported to the laboratory for measurement of photosynthesis (A), transpiration (E) and stomatal conductance (gs). Measurements of CO2 uptake were also made whilst the CO2 concentration within the leaf (Ci) was experimentally controlled (A/C, analysis). This revealed that higher rates of photosynthesis for lammas leaves grown in unfiltered air were due to enhanced regeneration of RuBP (increased Jmax P < 0.08). Carboxylation efficiency (dA/dCi) and percentage stomatal limitation were not significantly altered by air quality. Jmax and dA/dCi were similarly reduced following exposure to drought regardless of the air quality treatment. [ABSTRACT FROM AUTHOR]

To optimise trade-offs provided by future changes in grassland use intensity, spatially and temporally explicit estimates of respective grassland productivities are required at the systems level. Here, we benchmark the potential national availability of grassland biomass, identify optimal strategies for its management, and investigate the relative importance of intensification over reversion (prioritising productivity versus environmental ecosystem services). Process-conservative meta-models for different grasslands were used to calculate the baseline dry matter yields (DMY; 1961–1990) at 1 km 2 resolution for the whole UK. The effects of climate change, rising atmospheric [CO 2 ] and technological progress on baseline DMYs were used to estimate future grassland productivities (up to 2050) for low and medium CO 2 emission scenarios of UKCP09. UK benchmark productivities of 12.5, 8.7 and 2.8 t/ha on temporary, permanent and rough-grazing grassland, respectively, accounted for productivity gains by 2010. By 2050, productivities under medium emission scenario are predicted to increase to 15.5 and 9.8 t/ha on temporary and permanent grassland, respectively, but not on rough grassland. Based on surveyed grassland distributions for Great Britain in 2010 the annual availability of grassland biomass is likely to rise from 64 to 72 million tonnes by 2050. Assuming optimal N application could close existing productivity gaps of ca. 40% a range of management options could deliver additional 21 ∗ 10 6 tonnes of biomass available for bioenergy. Scenarios of changes in grassland use intensity demonstrated considerable scope for maintaining or further increasing grassland production and sparing some grassland for the provision of environmental ecosystem services. [ABSTRACT FROM AUTHOR]

• Anti-cancer glucosinolates are increased when watercress is grown in a soil system in California, relative to an aquatic system in the UK. • Higher antioxidants were quantified for watercress grown in the UK. • Morphological plasticity in response to contrasting environments was observed for watercress. • Watercress yield was highest in California, but leaf quality better in the UK. Watercress (Nasturtium officinale R. Br.; Brassicaceae) is a highly nutritious leafy green vegetable consumed globally, with a rich health-related phytonutrient profile that includes the secondary plant metabolites glucosinolates (GLS), especially gluconasturtiin and its hydrolysis product phenethyl isothiocyanate (PEITC). The peppery taste and pungency of watercress comes from these mustard oils, and they are known to help reduce inflammation and chronic damage in cells and have been shown to have a role in cancer prevention in vitro and in vivo. We explored how both genotype and highly contrasting environments of California (CA) and the United Kingdom (UK) alter phenotypic traits for a set of F 2 :4 genotypes created from a unique bi-parental cross, chosen for their extreme phenotypes for yield, leaf and branch morphology, antioxidant capacity, and glucosinolate content in two contrasting field locations. Although both genotype and environment had a significant impact on plant morphology, nutritional quality, and yield, overall, the highly contrasting environments of California and the UK, had a much stronger effect. Plants grown in CA had higher biomass, thicker main stem and more branches, and a higher concentration of aromatic GLS, whilst plants grown in the UK had larger leaves with longer stems, suggesting a better harvestable product, at least for a salad and not a soup crop. Significant G x E interactions were observed for multiple traits, suggesting significant phenotypic plasticity of watercress and variation between genotypes that will enable the selection of ideotypes suitable for these highly contrasting growth environments, that can be considered as the 'extremes' of an environmental gradient where the crop might be grown, from the warm and dry soil-grown conditions of California to the relatively cool and wet aquatic growing system of the UK. [Display omitted] [ABSTRACT FROM AUTHOR]