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Globally pervasive increases in atmospheric CO2 and nitrogen (N) deposition could have substantial effects on plant communities, either directly or mediated by their interactions with soil nutrient limitation. While the direct consequences of N enrichment on plant communities are well documented, potential interactions with rising CO2 and globally widespread phosphorus (P) limitation remain poorly understood. We investigated the consequences of simultaneous elevated CO2 (eCO2) and N and P additions on grassland biodiversity, community and functional composition in P‐limited grasslands. We exposed soil‐turf monoliths from limestone and acidic grasslands that have received >25 years of N additions (3.5 and 14 g m−2 year−1) and 11 (limestone) or 25 (acidic) years of P additions (3.5 g m−2 year−1) to eCO2 (600 ppm) for 3 years. Across both grasslands, eCO2, N and P additions significantly changed community composition. Limestone communities were more responsive to eCO2 and saw significant functional shifts resulting from eCO2–nutrient interactions. Here, legume cover tripled in response to combined eCO2 and P additions, and combined eCO2 and N treatments shifted functional dominance from grasses to sedges. We suggest that eCO2 may disproportionately benefit P acquisition by sedges by subsidising the carbon cost of locally intense root exudation at the expense of co‐occurring grasses. In contrast, the functional composition of the acidic grassland was insensitive to eCO2 and its interactions with nutrient additions. Greater diversity of P‐acquisition strategies in the limestone grassland, combined with a more functionally even and diverse community, may contribute to the stronger responses compared to the acidic grassland. Our work suggests we may see large changes in the composition and biodiversity of P‐limited grasslands in response to eCO2 and its interactions with nutrient loading, particularly where these contain a high diversity of P‐acquisition strategies or deve

Globally pervasive increases in atmospheric CO2 and nitrogen (N) deposition could have substantial effects on plant communities, either directly or mediated by their interactions with soil nutrient limitation. While the direct consequences of N enrichment on plant communities are well documented, potential interactions with rising CO2 and globally widespread phosphorus (P) limitation remain poorly understood. We investigated the consequences of simultaneous elevated CO2 (eCO2) and N and P additions on grassland biodiversity, community and functional composition in P-limited grasslands. We exposed soil-turf monoliths from limestone and acidic grasslands that have received >25 years of N additions (3.5 and 14 g m−2 year−1) and 11 (limestone) or 25 (acidic) years of P additions (3.5 g m−2 year−1) to eCO2 (600 ppm) for 3 years. Across both grasslands, eCO2, N and P additions significantly changed community composition. Limestone communities were more responsive to eCO2 and saw significant functional shifts resulting from eCO2–nutrient interactions. Here, legume cover tripled in response to combined eCO2 and P additions, and combined eCO2 and N treatments shifted functional dominance from grasses to sedges. We suggest that eCO2 may disproportionately benefit P acquisition by sedges by subsidising the carbon cost of locally intense root exudation at the expense of co-occurring grasses. In contrast, the functional composition of the acidic grassland was insensitive to eCO2 and its interactions with nutrient additions. Greater diversity of P-acquisition strategies in the limestone grassland, combined with a more functionally even and diverse community, may contribute to the stronger responses compared to the acidic grassland. Our work suggests we may see large changes in the composition and biodiversity of P-limited grasslands in response to eCO2 and its interactions with nutrient loading, particularly where these contain a high diversity of P-acquisition strategies or deve

Europe imports large amounts of soybean that are predominantly used for livestock feed, mainly sourced from Brazil, USA and Argentina. In addition, the demand for GM-free soybean for human consumption is project to increase. Soybean has higher protein quality and digestibility than other legumes, along with high concentrations of isoflavones, phytosterols and minerals that enhance the nutritional value as a human food ingredient. Here, we examine the potential to increase soybean production across Europe for livestock feed and direct human consumption, and review possible effects on the environment and human health. Simulations and field data indicate rainfed soybean yields of 3.1 ± 1.2 t ha−1 from southern UK through to southern Europe (compared to a 3.5 t ha−1 average from North America). Drought-prone southern regions and cooler northern regions require breeding to incorporate stress-tolerance traits. Literature synthesized in this work evidenced soybean properties important to human nutrition, health, and traits related to food processing compared to alternative protein sources. While acknowledging the uncertainties inherent in any modelling exercise, our findings suggest that further integrating soybean into European agriculture could reduce GHG emissions by 37–291 Mt CO2e year−1 and fertiliser N use by 0.6–1.2 Mt year−1, concurrently improving human health and nutrition.

Riparian zones are critical interfaces to freshwater systems, acting as gateways for the conveyance and modification of macronutrient fluxes from land to rivers and oceans. In this paper, we propose that certain riparian conditions and processes (conceptually ‘Riparian Reactive Interfaces’) may be susceptible to environmental change with consequences of accelerating local nutrient cycling cascading to global impacts on the cycles of carbon (C), nitrogen (N), and phosphorus (P). However, we argue that this concept is insufficiently understood and that research has not yet established robust baseline data to predict and measure change at the key riparian ecosystem interface. We suggest one contributing factor as lack of interdisciplinary study of abiotic and biotic processes linking C, N, and P dynamics and another being emphasis on riparian ecology and restoration that limits frameworks for handling and scaling topography–soil–water–climate physical and biogeochemical observations from plot to large catchment scales. Scientific effort is required now to evaluate riparian current and future controls on global nutrient cycles through multi-nutrient (and controlling element) studies, grounded in landscape frameworks for dynamic riparian behaviour variation, facilitating scaling to catchment predictions.

The importance of soils to society has gained increasing recognition over the past decade, with the potential to contribute to most of the United Nations’ Sustainable Development Goals (SDGs). With unprecedented and growing demands for food, water and energy, there is an urgent need for a global effort to address the challenges of climate change and land degradation, whilst protecting soil as a natural resource. In this paper, we identify the contribution of soil science over the past decade to addressing gaps in our knowledge regarding major environmental challenges: climate change, food security, water security, urban development, and ecosystem functioning and biodiversity. Continuing to address knowledge gaps in soil science is essential for the achievement of the SDGs. However, with limited time and budget, it is also pertinent to identify effective methods of working that ensure the research carried out leads to real-world impact. Here, we suggest three strategies for the next decade of soil science, comprising a greater implementation of research into policy, interdisciplinary partnerships to evaluate function trade-offs and synergies between soils and other environmental domains, and integrating monitoring and modelling methods to ensure soil-based policies can withstand the uncertainties of the future.

Phosphorus (P) is a key limiting factor in crop growth and essential for agriculture. As plant uptake of P is inefficient, it is commonly applied to maintain crop yields leading to a range of negative environmental issues when applied in excess. Additionally, P in mineral fertilisers is derived from mined rock phosphate, which is a finite resource that needs to be sustainably managed in order to maintain food security in the long-term. Phosphatase activity is one of several mechanistic responses to P deficiency in the plant-soil system, enabling the mineralization of organic P to increase P availability for both plants and soil organisms. In this study we address the need to further understanding of the role of phosphatase enzyme activity in P acquisition in agricultural settings, using a systematic review of the literature and subsequent meta-analysis. We find that monoesterase activity is inhibited by availability of inorganic P (−23%, −39.8 - -2.2%) yet is enhanced by the availability of organic P (+74%, 8.4–232.1%). This indicates that phosphatase enzyme activity is important in P deficient agricultural systems, yet that the availability of organic P is more important in determining phosphatase activity than the level of P deficiency. We also investigated the role of other factors such as nitrogen addition, pH of growth substrate and changes in plant composition and physiology but, none of these factors explained significant variance in the data. We highlight need for consistent recording and reporting of additional variables in association with phosphatase enzyme assay data, which is required to enable quantification of the potential utilisation of organic P resources in agriculture, and the contribution of phosphatase activity to P acquisition in both agricultural and semi-natural ecosystems.

The importance of soils to society has gained increasing recognition over the past decade, with the potential to contribute to most of the United Nations’ Sustainable Development Goals (SDGs). With unprecedented and growing demands for food, water and energy, there is an urgent need for a global effort to address the challenges of climate change and land degradation, whilst protecting soil as a natural resource. In this paper, we identify the contribution of soil science over the past decade to addressing gaps in our knowledge regarding major environmental challenges: climate change, food security, water security, urban development, and ecosystem functioning and biodiversity. Continuing to address knowledge gaps in soil science is essential for the achievement of the SDGs. However, with limited time and budget, it is also pertinent to identify effective methods of working that ensure the research carried out leads to real-world impact. Here, we suggest three strategies for the next decade of soil science, comprising a greater implementation of research into policy, interdisciplinary partnerships to evaluate function trade-offs and synergies between soils and other environmental domains, and integrating monitoring and modelling methods to ensure soil-based policies can withstand the uncertainties of the future.

Carbon sequestration (Cseq) in soils and plant biomass is viewed as an important means of mitigating climate change. Recent global assessments have estimated considerable potential for terrestrial Cseq, but generally lack sensitivity to climate warming, nutrient limitations and perspective on local land use. These are important factors since higher temperatures can accelerate the decomposition of soil organic matter, nutrient availability affects plant productivity, while land use pressures put broader constraints on terrestrial organic matter inputs and storage. Here, we explore the potential for Cseq under changing land use, climate and nutrient conditions in a UK-based national scale case study. We apply an integrated terrestrial C–N–P cycle model with representative ranges of high-resolution climate and land use scenarios to estimate Cseq potential across the UK. If realistic UK targets for grassland restoration and afforestation over the next 30 years are met, we estimate that an additional 120 TgC could be sequestered by 2100 (similar to current annual UK greenhouse gas emissions or roughly 7% of net emission cuts needed in meeting net zero), conditional on climate change of <2 °C. Conversely, we estimate that UK arable expansion would reduce terrestrial carbon storage by a similar magnitude. The most pessimistic climate trajectories are predicted to cause net losses in UK soil carbon storage under all land use scenarios. Warmer climates substantially reduce the potential total terrestrial carbon storage gains offered by afforestation and grassland restoration. We conclude that although concerted land use change could make an important moderate contribution to national level Cseq for countries like the UK, soil Cseq only provides a contribution if we are on a low emission pathway, and is therefore conditional on deep global cuts to emissions from fossil fuels, deforestation and soil degradation.

Carbon sequestration (Cseq) in soils and plant biomass is viewed as an important means of mitigating climate change. Recent global assessments have estimated considerable potential for terrestrial Cseq, but generally lack sensitivity to climate warming, nutrient limitations and perspective on local land use. These are important factors since higher temperatures can accelerate the decomposition of soil organic matter, nutrient availability affects plant productivity, while land use pressures put broader constraints on terrestrial organic matter inputs and storage. Here, we explore the potential for Cseq under changing land use, climate and nutrient conditions in a UK-based national scale case study. We apply an integrated terrestrial C–N–P cycle model with representative ranges of high-resolution climate and land use scenarios to estimate Cseq potential across the UK. If realistic UK targets for grassland restoration and afforestation over the next 30 years are met, we estimate that an additional 120 TgC could be sequestered by 2100 (similar to current annual UK greenhouse gas emissions or roughly 7% of net emission cuts needed in meeting net zero), conditional on climate change of <2 °C. Conversely, we estimate that UK arable expansion would reduce terrestrial carbon storage by a similar magnitude. The most pessimistic climate trajectories are predicted to cause net losses in UK soil carbon storage under all land use scenarios. Warmer climates substantially reduce the potential total terrestrial carbon storage gains offered by afforestation and grassland restoration. We conclude that although concerted land use change could make an important moderate contribution to national level Cseq for countries like the UK, soil Cseq only provides a contribution if we are on a low emission pathway, and is therefore conditional on deep global cuts to emissions from fossil fuels, deforestation and soil degradation.

The importance of soils to society has gained increasing recognition over the past decade, with the potential to contribute to most of the United Nations’ Sustainable Development Goals (SDGs). With unprecedented and growing demands for food, water and energy, there is an urgent need for a global effort to address the challenges of climate change and land degradation, whilst protecting soil as a natural resource. In this paper, we identify the contribution of soil science over the past decade to addressing gaps in our knowledge regarding major environmental challenges: climate change, food security, water security, urban development, and ecosystem functioning and biodiversity. Continuing to address knowledge gaps in soil science is essential for the achievement of the SDGs. However, with limited time and budget, it is also pertinent to identify effective methods of working that ensure the research carried out leads to real-world impact. Here, we suggest three strategies for the next decade of soil science, comprising a greater implementation of research into policy, interdisciplinary partnerships to evaluate function trade-offs and synergies between soils and other environmental domains, and integrating monitoring and modelling methods to ensure soil-based policies can withstand the uncertainties of the future.

Long-term urban heat island (UHI) observations are uncommon and where available, are generally unable to distinguish changing climate drivers from urban expansion; neither driver is treated independently. We overcome this limitation using a generalized additive model to learn the variability in UHI intensity (UHII) at a central London weather station (St James’s Park) over a 10-year observation period (2010–2019). We then use the model to reconstruct 70 years (1950–2019) of monthly night-time UHII variability using ERA5 reanalysis data both as a reference in UHII calculation and for the predictors. We find considerable variability both seasonally and annually within the UHII time series (monthly mean maximum UHIIs are 1.4–2.9oC). Applying extreme value analysis to the time series we show that monthly mean maximum UHIIs are likely to exceed 2.75oC once every 11 years. Considering that most studies observe or model UHIIs for less than a year, they will likely misrepresent this UHII variability. Nevertheless, despite moving to a warmer background climate, London’s UHII has not significantly changed across the period of analysis (1950–2019). The data-driven methods we create in this study are easily transferable to other cities.

As a result of growing food demands, the area of land used globally for agriculture has rapidly increased over the last 300 years. Clearance of natural vegetation and conversion of land to agriculture is often associated with terrestrial carbon loss, from both vegetation and soil stores. Changes in terrestrial carbon storage has implications for food production, climate and water regulation. Quantifying these changes is therefore vital to understand the risks to and resilience of these benefits. Land use in the East of England has significantly changed during this period and is now predominantly used for agriculture, specifically arable use. In order to map changes to terrestrial carbon storage in this region since 1700, we apply a plant–soil system biogeochemistry model, N14CP. The model indicates carbon storage in the East of England has decreased by 109 Mt (−35.7%) during the study period, and whilst losses are observed in both soil and vegetation stores, vegetation losses as a result of forest clearance dominate. These findings have implications for carbon sequestration strategies; the largest carbon storage gains within the region are likely to be achieved through land-use transitions such as afforestation, rather than soil sequestration through changing arable management practices.

Ecosystems limited in phosphorous (P) are widespread, yet there is limited understanding of how these ecosystems may respond to anthropogenic deposition of nitrogen (N) and the interconnected effects on the biogeochemical cycling of carbon (C), N, and P. Here, we investigate the consequences of enhanced N addition for the C–N–P pools of two P-limited grasslands, one acidic and one limestone, occurring on contrasting soils, and we explore their responses to a long-term nutrient-manipulation experiment. We do this by combining data with an integrated C–N–P cycling model (N14CP). We explore the role of P-access mechanisms by allowing these to vary in the modelling framework and comparing model plant–soil C–N–P outputs to empirical data. Combinations of organic P access and inorganic P availability most closely representing empirical data were used to simulate the grasslands and quantify their temporal response to nutrient manipulation. The model suggested that access to organic P is a key determinant of grassland nutrient limitation and responses to experimental N and P manipulation. A high rate of organic P access allowed the acidic grassland to overcome N-induced P limitation, increasing biomass C input to soil and promoting soil organic carbon (SOC) sequestration in response to N addition. Conversely, poor accessibility of organic P for the limestone grassland meant N provision exacerbated P limitation and reduced biomass input to the soil, reducing soil carbon storage. Plant acquisition of organic P may therefore play an important role in reducing P limitation and determining responses to anthropogenic changes in nutrient availability. We conclude that grasslands differing in their access to organic P may respond to N deposition in contrasting ways, and where access is limited, soil organic carbon stocks could decline.

Carbon stores in the terrestrial biosphere globally represent over 50% of present-day organic carbon reservoirs and have significantly altered over the last three centuries owing to anthropogenic disturbances. Conversion of natural land to agricultural uses often results in a loss of soil carbon, whilst atmospheric deposition of pollutants such as nitrogen has increased carbon storage in both soil and biomass. Terrestrial carbon storage underpins a range of ecosystem services, including climate regulation, food production, and water services. This storage is crucial for sustainable land management. Quantification of terrestrial carbon cycling at regional and national scales, and understanding how human-induced drivers have impacted present-day carbon stores is therefore required to inform sustainable land use policy. This study applies the N14CP model, an integrated soil-plant biogeochemistry carbon-nitrogen-phosphorus model, across the United Kingdom to simulate changes in terrestrial carbon storage from 1700 to 2020. The analysis shows that change in anthropogenic terrestrial carbon storage is a complex picture comprising of gains in natural areas due to nitrogen deposition and afforestation, and losses in arable areas. We observed an overall net increase in total terrestrial carbon storage of 6.9%. We note, however, that continued increases in carbon storage cannot be assumed due to (i) reduced influence of future nitrogen deposition as these systems become limited by other nutrients, (ii) the need to continue enhanced nitrogen inputs to maintain carbon sequestered, and (iii) carbon declines in arable areas continuing alongside diminishing gains in other land use types. This research provides a full picture of anthropogenic impacts on terrestrial organic carbon storage, accounting for changing nutrient cycles at a national scale.

Understanding how agricultural practices alter biogeochemical cycles is vital for maintaining land productivity, food security, and other ecosystem services such as carbon sequestration. However, these are complex, highly coupled long-term processes that are difficult to observe or explore through empirical science alone. Models are required that capture the main anthropogenic disturbances, whilst operating across regions and long timescales, simulating both natural and agricultural environments, and shifts among these. Many biogeochemical models neglect agriculture or interactions between carbon and nutrient cycles, which is surprising given the scale of intervention in nitrogen and phosphorus cycles introduced by agriculture. This gap is addressed here, using a plant-soil model that simulates integrated soil carbon, nitrogen and phosphorus (CNP) cycling across natural, semi-natural and agricultural environments. The model is rigorously tested both spatially and temporally using data from long-term agricultural experiments across temperate environments. The model proved capable of reproducing the magnitude of and trends in soil nutrient stocks, and yield responses to nutrient addition. The model has potential to simulate anthropogenic effects on biogeochemical cycles across northern Europe, for long timescales (centuries) without site-specific calibration, using easily accessible input data. The results demonstrate that weatherable P from parent material has a considerable effect on modern pools of soil C and N, despite significant perturbation of nutrient cycling from agricultural practices, highlighting the need to integrate both geological and agricultural processes to understand effects of land-use change on food security, C storage and nutrient sustainability. The results suggest that an important process or source of P is currently missing in our understanding of agricultural biogeochemical cycles. The model could not explain how yields were sustained in plot

Throughout the Anthropocene, the conversion of land to agriculture and atmospheric deposition of nitrogen have resulted in significant changes to biogeochemical cycling, including soil carbon stocks. Quantifying these changes is complex due to a number of influential factors (including climate, land use management, soil type) and their interactions. As the largest terrestrial store of carbon, soils are a key component in climate regulation. In addition, soil carbon storage contributes to numerous ecosystem services including food provision. It is therefore imperative that we understand changes to soil carbon stocks, and provide effective strategies for their future management. Modelling soil systems provides a means to estimate changes to soil carbon stocks. Due to linkages between the carbon cycle and other major nutrient cycles (notably nitrogen and phosphorus which often limit the productivity of ecosystems), models of integrated nutrient cycling are required to understand the response of the carbon cycle to global pressures. Simulating the impacts of land use changes requires capacity to model both semi-natural and intensive agricultural systems. In this study, we have developed an integrated carbon-nitrogen-phosphorus model of semi-natural systems to include representation of both arable and grassland systems, and a range of agricultural management practices. The model is applicable to large spatial scales, as it uses readily available input data and does not require site-specific calibration. After being validated both spatially and temporally using data from long-term experimental sites across Northern-Europe, the model was applied at a national scale throughout the United Kingdom to assess the impacts of land use change and management practices during the last two centuries. Results indicate a decrease in soil carbon in areas of agricultural expansion, yet in areas of semi-natural land use, atmospheric deposition of nitrogen has resulted in increased net pri

Soils provide us with multiple essential services, such as food production, water flow regulation, and climate regulation. The loss of soil function endangers provision of these services, in turn endangering the local, regional and global societies and economies that rely on these. Soils, therefore, are in effect a critical infrastructure, which can be defined as an asset, system or process, the loss or compromise of which could result in a major detrimental impact on the availability, integrity or delivery of essential services, with significant economic or social impacts. Conceptualising soil as a critical infrastructure changes the way we as a society need to approach its management. For example, government authorities have a responsibility to reduce the vulnerability of critical infrastructure, and strengthen their security and resilience. To meet this responsibility there is a need to assess infrastructure resilience, identify critical vulnerabilities, and identify and implement strategies for increasing resilience. There has been growing interest and research on soil resilience, particularly drawing on ecological resilience concepts. In this contribution, we will consider our current understanding of soil system resilience from a critical infrastructure perspective and discuss where further science is needed.

In this study, we explore plausible future states of soil organic matter, biomass, food production and soil greenhouse gas emissions across the UK under a range of climate, land use and land management scenarios. We use state-of-the-art soil biochemistry model, N14CP-Ag, combined with UKCP18 climate scenarios and ASSET land cover change and crop scenarios mapped onto a UK-wide grid with around 100,000 land parcels. Historic runs cover the period from the start of the Holocene interglacial (-12 kyr BP) to 2015; scenarios run from 2016 out to 2100. The results show variations of soil organic carbon (SOC) of around 10% between 2016 and 2100 relative to the simulated starting value of 1.4 Gton in 2015, with reductions of up to 7% under arable expansion scenarios and increases of up to 3% under grassland restoration scenarios. The effect of changing cropping patterns on UK-wide SOC is comparatively small. As climate scenarios move from lower to higher global emissions, the SOC reductions under arable expansion become more pronounced, while the SOC increases under grassland restoration diminish and eventually turn into losses. UK-wide crop yields show resilience to climate change and are maximised for the arable expansion scenario with protected sites of special scientific interest. Soil CO2 and nitrogen emissions get progressively higher in warmer climates. The results of this study are expected to contribute to a future UK agricultural policy aimed at rewarding farmers for sustainable land management practices.