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A major challenge in soil science is to monitor and understand the state and change of soils at a national scale to inform decision making and policy. To address this, there is a need to identify key parameters for soil health and function and determine how they relate to other parameters, including traditional soil surveys. Here we present a national‐scale dataset of topsoil sampled as part of a wider agri‐environment monitoring scheme in Wales, UK. Over 1,350 topsoils (0–15 cm) were sampled across a very wide range of habitats and a range of physical, chemical and biological soil quality indicators were measured. We show consistent differences in soil physicochemical properties across habitat types, with carbon decreasing and pH increasing across the habitat productivity gradient from bogs through woodlands and grasslands to arable systems. The soils within our dataset are largely within the limits identified as important for supporting habitat function, with the exception of excessive phosphate levels in mesotrophic grassland. Cluster detection methods identified four soil functional classes based on measured topsoil properties, which were more related to habitat type than the genesis‐based soil classification from soil maps. These soil functional classes can be interpreted as phenoforms within the soil genoforms found by traditional soil classification. This shows the importance of land‐use management in determining the soil health and functional capacity of soils. Our work provides an account of the current state of soil health in Wales, its relationship to soil function and a baseline for future monitoring to track changes against agri‐environment and other policy targets. Highlights: We measured soil physicochemical properties in ~1,350 sites in a variety of temperate habitatsThere was a strong gradient in soil carbon and pH, with other variables being correlated with theseMesotrophic grassland sites had phosphate levels above the identified limit for good functioningSoil classes from topsoil properties were more related to land use than soil map classifications [ABSTRACT FROM AUTHOR]

Grassland fertilisation drives non‐random plant loss resulting in areas dominated by perennial grass species. How these changes cascade through linked trophic levels, however, is not well understood.We studied how grassland fertilisation propagates change through the plant assemblage into the plant–flower‐visitor, plant–leaf miner and leaf miner–parasitoid networks using a year's data collection from a long‐term grassland fertiliser application experiment. Our experiment had three fertiliser treatments each applied to replicate plots 15 m2 in size: mineral fertiliser, farmyard manure, and mineral fertiliser and farmyard manure combined, along with a control of no fertiliser.The combined treatment had the most significant impact, and both plant species richness and floral abundance decreased with the addition of fertiliser. While insect species richness was unaffected by fertiliser treatment, fertilised plots had a significantly higher abundance of leaf miners and parasitoids and a significantly lower abundance of bumblebees. The plant–flower‐visitor and plant–herbivore networks showed higher values of vulnerability and lower modularity with fertiliser addition, while leaf miner–parasitoid networks showed a rise in generality.The different groups of insects were impacted by fertilisers to varying degrees: while the effect on abundance was the highest for leaf miners, the vulnerability and modularity of flower‐visitor networks was the most affected. The impact on the abundance of leaf miners was positive and three times higher than the impact on parasitoids, and the impact on bumblebee abundance was negative and double the magnitude of impact on flower abundance.Overall, our results show that while insect species richness was unaffected by fertilisers, network structure changed significantly as the replacement of forbs by grasses resulted in changes in relative abundance across trophic levels, with the direction of change depending on the type of network.Synthesis. By studying multiple networks simultaneously, we were able to rank the relative impact of habitat change on the different groups of species within the community. This provided a more holistic picture of the impact of agricultural intensification and provides useful information when deciding on priorities for mitigation. [ABSTRACT FROM AUTHOR]

This paper presents an alternative approach for high spatial resolution vegetation productivity mapping at a regional scale, using a combination of Normalised Difference Vegetation Index (NDVI) imagery and widely distributed ground-based Above-ground Net Primary Production (ANPP) estimates. Our method searches through all available single-date NDVI imagery to identify the images which give the best NDVI-ANPP relationship. The derived relationships are then used to predict ANPP values outside of field survey plots. This approach enables the use of the high spatial resolution (30 m) Landsat 8 sensor, despite its low revisit frequency that is further reduced by cloud cover. This is one of few studies to investigate the NDVI-ANPP relationship across a wide range of temperate habitats and strong relationships were observed (R² = 0.706), which increased when only grasslands were considered (R² = 0.833). The strongest NDVI-ANPP relationships occurred during the spring "green-up" period. A reserved subset of 20% of ground-based ANPP estimates was used for validation and results showed that our method was able to estimate ANPP with a RMSE of 15-21%. This work is important because we demonstrate a general methodological framework for mapping of ANPP from local to regional scales, with the potential to be applied to any temperate ecosystems with a pronounced green up period. Our approach allows spatial extrapolation outside of field survey plots to produce a continuous surface product, useful for capturing spatial patterns and representing small-scale heterogeneity, and well-suited for modelling applications. The data requirements for implementing this approach are also discussed. [ABSTRACT FROM AUTHOR]

The Countryside Survey (CS) of Great Britain (GB) provides a unique and statistically robust series of datasets, consisting of an extensive set of repeated ecological measurements at a national scale, covering a time span of 29 years. CS was first undertaken in 1978 to provide a baseline for ecological and land use change monitoring in the rural environment of GB, following a stratified random design, based on 1 km squares. Originally, eight random 1 km squares were drawn from each of 32 environmental classes, thus comprising 256 sample squares in the 1978 survey. The number of these sites increased to 382 in 1984, 506 in 1990, 569 in 1998 and 591 in 2007. Detailed information regarding vegetation types and land use was mapped in all five surveys, allowing reporting by defined standard habitat classifications. Additionally, point and linear landscape features (such as trees and hedgerows) are available from all surveys after 1978. From these stratified, randomly located sample squares, information can be converted into national estimates, with associated error terms. Other data, relating to soils, freshwater and vegetation, were also sampled on analogous dates. However, the present paper describes only the surveys of landscape features and habitats. The resulting datasets provide a unique, comprehensive, quantitative ecological coverage of extent and change in these features in GB. Basic results are presented and their implications discussed. However, much opportunity for further analyses remains. Data from each of the survey years are available via the following DOIs: Landscape area data 1978: http://doi.org/10.5285/86c017ba-dc62-46f0-ad13-c862bf31740e, 1984: http://doi.org/10.5285/b656bb43-448d-4b2c-aade-7993aa243ea3, 1990: http://doi.org/10.5285/94f664e5-10f2-4655-bfe6-44d745f5dca7, 1998: http://doi.org/10.5285/1e050028-5c55-42f4-a0ea-c895d827b824, and 2007: http://doi.org/10.5285/bf189c57-61eb-4339-a7b3-d2e81fdde28d; Landscape linear feature data 1984: http://doi.org/10.5285/a3f5665c-94b2-4c46-909e-a98be97857e5, 1990: http://doi.org/10.5285/311daad4-bc8c-485a-bc8a-e0d054889219, 1998: http://doi.org/10.5285/8aaf6f8c-c245-46bb-8a2a-f0db012b2643, and 2007: http://doi.org/10.5285/e1d31245-4c0a-4dee-b36c-b23f1a697f88; Landscape point feature data 1984: http://doi.org/10.5285/124b872e-036e-4dd3-8316-476b5f42c16e, 1990: http://doi.org/10.5285/1481bc63-80d7-4d18-bcba-8804aa0a9e1b, 1998: http://doi.org/10.5285/ed10944f-40c8-4913-b3f5-13c8e844e153, and 2007: http://doi.org/10.5285/55dc5fd7-d3f7-4440-b8a7-7187f8b0550b. [ABSTRACT FROM AUTHOR]

Since 1978, a series of national surveys (Countryside Surveys) have been carried out by the Centre for Ecology and Hydrology (formerly the Institute of Terrestrial Ecology) to gather data on the natural environment in Great Britain. As the sampling framework for these surveys is not optimised to yield data on rarer or more specialised habitats, a survey was commissioned by the then Department of the Environment (DOE, now the Department for Environment Food & Rural Affairs, DEFRA), in the 1990s to carry out additional survey work in English landscapes which contained semi-natural habitats that were perceived to be under threat, or which represented areas of concern to the Ministry. The landscapes were: lowland heath, chalk and limestone grasslands, coasts and uplands. These landscapes were chosen from a list identified as 'key habitats' in the Countryside Stewardship Scheme, an agri-environment scheme initiated in 1991. The survey design was a series of gridded, stratified, randomly selected 1 km squares taken as representative of classes derived from environmental classifications (or spatial masks) for each of the four landscape types in England determined from a statistical land classification. This resulted in a total of 213 of these squares being surveyed in the summers of 1992 and 1993, with information being collected regarding vegetation species, land cover, landscape features and land use. Data from the survey were collected using standardised, repeatable methods, with the database now providing a valuable baseline against which future ecological changes, resulting from a range of different drivers, may be compared. Following the surveys, the data were analysed and described in a series of contract reports showing that valuable habitats were restricted in all landscapes and that the majority were within designated land. The data set provides major potential for analyses, beyond those published in the reports published in 1996, for example in relation to climate change, agri-environment policies and land management. Precise locations of the plots are restricted, largely for reasons of landowner confidentiality. However, the representative nature of the data set makes it highly valuable for evaluating the status of the associated landscapes and vegetation covered. Both land cover data and vegetation plot data were collected during the surveys in 1992 and 1993, and are available via the following DOI: https://doi.org/10.5285/7aefe6aa-0760-4b6d-9473-fad8b960abd4. The spatial masks are also available from: https://doi.org/10.5285/dc583be3-3649-4df6-b67e-b0f40b4ec895. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition has been identified as a major threat to biodiversity, but field surveys of its effects have rarely focussed on sites which are actively managed to maintain characteristic species. We analysed permanent quadrat data from 106 plots in nature reserves on calcareous grassland sites in the United Kingdom collected during a survey between 1990 and 1993 and compared the data with the results from resurvey of 48 of these plots between 2006 and 2009. N deposition showed no significant spatial association with species richness, species diversity, or the frequency of species adapted to low nutrient conditions in the 1990-1993 dataset. However, temporal analysis showed that N deposition was significantly associated with changes in Shannon diversity and evenness. In plots with high rates of N deposition, there was a decrease in species diversity and evenness, a decline in the frequency of characteristic calcareous grassland species, and a lower number of rare and scarce species. As all sites had active management to maintain a high diversity and characteristic species, our results imply that even focussed management on nature conservation objectives cannot prevent adverse effects of high rates of N deposition. Structural equation modelling was used to compare different causal mechanisms to explain the observed effects. For change in Shannon diversity, direct effects of N deposition were the dominant mechanism and there was an independent effect of change in grazing intensity. In contrast, for change in herb species number, indirect effects on soil acidity, linked to both N and S deposition, were more important than direct effects of N deposition. [ABSTRACT FROM AUTHOR]

Globally pervasive increases in atmospheric CO 2 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 CO 2 and globally widespread phosphorus (P) limitation remain poorly understood. We investigated the consequences of simultaneous elevated CO 2 (eCO 2 ) 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 eCO 2 (600 ppm) for 3 years. Across both grasslands, eCO 2 , N and P additions significantly changed community composition. Limestone communities were more responsive to eCO 2 and saw significant functional shifts resulting from eCO 2 -nutrient interactions. Here, legume cover tripled in response to combined eCO 2 and P additions, and combined eCO 2 and N treatments shifted functional dominance from grasses to sedges. We suggest that eCO 2 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 eCO 2 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 eCO 2 and its interactions with nutrient loading, particularly where these contain a high diversity of P-acquisition strategies or developmentally young soils with sufficient bioavailable mineral P., (© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Plant communities are being exposed to changing environmental conditions all around the globe, leading to alterations in plant diversity, community composition, and ecosystem functioning. For herbaceous understorey communities in temperate forests, responses to global change are postulated to be complex, due to the presence of a tree layer that modulates understorey responses to external pressures such as climate change and changes in atmospheric nitrogen deposition rates. Multiple investigative approaches have been put forward as tools to detect, quantify and predict understorey responses to these global-change drivers, including, among others, distributed resurvey studies and manipulative experiments. These investigative approaches are generally designed and reported upon in isolation, while integration across investigative approaches is rarely considered. In this study, we integrate three investigative approaches (two complementary resurvey approaches and one experimental approach) to investigate how climate warming and changes in nitrogen deposition affect the functional composition of the understorey and how functional responses in the understorey are modulated by canopy disturbance, that is, changes in overstorey canopy openness over time. Our resurvey data reveal that most changes in understorey functional characteristics represent responses to changes in canopy openness with shifts in macroclimate temperature and aerial nitrogen deposition playing secondary roles. Contrary to expectations, we found little evidence that these drivers interact. In addition, experimental findings deviated from the observational findings, suggesting that the forces driving understorey change at the regional scale differ from those driving change at the forest floor (i.e., the experimental treatments). Our study demonstrates that different approaches need to be integrated to acquire a full picture of how understorey communities respond to global change., (© 2023 John Wiley & Sons Ltd.)