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There is an increasing trend in promoting the use of biofuels for transportation as a low-fossil carbon energy source, but little knowledge on their multidimensional environmental impacts. Whole-system approaches, such as life cycle assessment (LCA), have been extensively employed to analyze the environmental performance of different biofuels. However, it remains unclear to which extent biofuels impact ecosystems and the services they provide, in particular related to different management practices. To overcome this challenge, this paper draws recommendations to better holistically address ecosystem services (ES) in LCA, with a focus on biofuels. We first pinpoint some of the challenges in accounting for the concept of ES in decision-making and review some of the existing ES classification frameworks and the usefulness of the cascade model. Second, we discuss the implications of identified context-specific aspects on the modeling of biofuel production impacts on ES in LCA. Finally, we propose a conceptual framework to link ES classification systems, the cascade model and the LCA approach. Although some challenges still remain unsolved, due to the existing life cycle impact assessment structure, existing ES frameworks and the cascade model are helpful tools to better include ES into LCA of different biofuels.

We have synthesized available data for calcium (Ca) dynamics in decomposing foliar litter of mainly pine (Pinus), spruce (Picea), and birch (Betula) species to determine patterns of Ca concentration with climate in newly shed litter and its dynamics in decomposing litter as well as a possible role for Ca as regards limit values. Initial Ca concentration was negatively related to mean annual precipitation (MAP) with different relationships among genera. A limited data set showed a positive relationship across species (p In decomposing litter, Ca concentration followed a negative quadratic (Ca = a + t − t2) function and had a maximum, which was variable. The Ca maximum concentration during decomposition was positively related to initial Ca concentration both within and among species. Separate linear relationships based on species were combined into one, in common for all investigated species and genera (R2 = 0.914, n = 63, p Limit values for decomposition were positively related to maximum Ca concentration at p Calcium net release started directly after the incubation and was linear to accumulated mass loss of litter, giving a slope coefficient for each study. The net release rates were linear to initial Ca concentration both within and across species/genera. All studies combined gave a negative linear relationship (R2 = 0.894, n = 67, p

Changing environmental conditions may substantially interact with site quality and forest stand characteristics, and impact forest growth and carbon sequestration. Understanding the impact of the various drivers of forest growth is therefore critical to predict how forest ecosystems can respond to climate change. We conducted a continental-scale analysis of recent (1995–2010) forest volume increment data (ΔVol, m3 ha−1 yr−1), obtained from ca. 100,000 coniferous and broadleaved trees in 442 even-aged, single-species stands across 23 European countries. We used multivariate statistical approaches, such as mixed effects models and structural equation modelling to investigate how European forest growth respond to changes in 11 predictors, including stand characteristics, climate conditions, air and site quality, as well as their interactions. We found that, despite the large environmental gradients encompassed by the forests examined, stand density and age were key drivers of forest growth. We further detected a positive, in some cases non-linear effect of N deposition, most pronounced for beech forests, with a tipping point at ca. 30 kg N ha−1 yr−1. With the exception of a consistent temperature signal on Norway spruce, climate-related predictors and ground-level ozone showed much less generalized relationships with ΔVol. Our results show that, together with the driving forces exerted by stand density and age, N deposition is at least as important as climate to modulate forest growth at continental scale in Europe, with a potential negative effect at sites with high N deposition.

International audience; Global forest loss and fragmentation have strongly increased the frequency of forest patches smaller than a few hectares. Little is known about the biodiversity and ecosystem service supply potential of such small woodlands in comparison to larger forests. As it is widely recognized that high biodiversity levels increase ecosystem functionality and the delivery of multiple ecosystem services, small, isolated woodlands are expected to have a lower potential for ecosystem service delivery than large forests hosting more species. We collected data on the diversity of six taxonomic groups covering invertebrates, plants and fungi, and on the supply potential of five ecosystem services and one disservice within 224 woodlands distributed across temperate Europe. We related their ability to simultaneously provide multiple ecosystem services (multiservice delivery potential) at different performance levels to biodiversity of all studied taxonomic groups (multidiversity), forest patch size and age, as well as habitat availability and connectivity within the landscape, while accounting for macroclimate, soil properties and forest structure. Unexpectedly, despite their lower multidiversity, smaller woodlands had the potential to deliver multiple services at higher performance levels per area than larger woodlands of similar age, probably due to positive edge effects on the supply potential of several ecosystem services. Biodiversity only affected multiservice delivery potential at a low performance level as well as some individual ecosystem services. The importance of other drivers of ecosystem service supply potential by small woodlands in agricultural landscapes also depended on the level of performance and varied with the individual ecosystem service considered. Synthesis and applications. Large, ancient woodlands host high levels of biodiversity and can therefore deliver a number of ecosystem services. In contrast, smaller woodlands in agricultural landscapes, especially ancient woodlands, have a higher potential to deliver multiple ecosystem services on a per area basis. Despite their important contribution to agricultural landscape multifunctionality, small woodlands are not currently considered by public policies. There is thus an urgent need for targeted policy instruments to ensure their adequate management and future conservation in order to either achieve multiservice delivery at high levels or to maximize the delivery of specific ecosystem services.

Wet deposition to Sweden has been measured on a monthly basis since 1955. Data from all national and international precipitation chemistry networks operating in Sweden during 1955–2017 was collected in one unique database. During 1990–2000, 146 sites were operated on average and the spatial distribution of deposition across Sweden was determined. The measurement sites were divided into three regions representing southwestern, southeastern and northern Sweden. The three regions clearly differ in deposition amount while the temporal variations were similar between the regions. Non-sea-salt sulphate (nss-SO42-) wet deposition reached a maximum around 1970 and ammonium (NH4+) and nitrate (NO3−) in the mid-1980s. There was a reasonable agreement between the decreasing wet deposition trends of NH4+ and nss-SO42-, during 1990–2016 and the estimated decrease in the emissions in Sweden and Europe. The decreasing wet deposition trend of NO3− was, however, weaker than the corresponding estimated reduction in emissions of NOx. The wet depositions of NH4+ and NO3− were similar in magnitude during the whole measurement period and distributed in a similar manner between the three regions despite that these pollutants are transported over long distances and that the sources and atmospheric chemistry for NHx and NOx are different. Keywords: Precipitation chemistry, Long-term time trends, Spatial distribution, Inter-annual variations, Ammonium, Nitrate, Non-sea-salt sulphate

International audience; Published by Copernicus Publications on behalf of the European Geosciences Union. 5568 M. Camino-Serrano et al.: Trends in soil solution dissolved organic carbon Abstract. Dissolved organic carbon (DOC) in surface waters is connected to DOC in soil solution through hydrological pathways. Therefore, it is expected that long-term dynamics of DOC in surface waters reflect DOC trends in soil solution. However, a multitude of site studies have failed so far to establish consistent trends in soil solution DOC, whereas increasing concentrations in European surface waters over the past decades appear to be the norm, possibly as a result of recovery from acidification. The objectives of this study were therefore to understand the long-term trends of soil solution DOC from a large number of European forests (ICP Forests Level II plots) and determine their main physico-chemical and biological controls. We applied trend analysis at two levels: (1) to the entire European dataset and (2) to the individual time series and related trends with plot characteristics , i.e., soil and vegetation properties, soil solution chemistry and atmospheric deposition loads. Analyses of the entire dataset showed an overall increasing trend in DOC concentrations in the organic layers, but, at individual plots and depths, there was no clear overall trend in soil solution DOC. The rate change in soil solution DOC ranged between −16.8 and +23 % yr −1 (median = +0.4 % yr −1) across Eu-rope. The non-significant trends (40 %) outnumbered the increasing (35 %) and decreasing trends (25 %) across the 97 ICP Forests Level II sites. By means of multivariate statistics , we found increasing trends in DOC concentrations with increasing mean nitrate (NO − 3) deposition and increasing trends in DOC concentrations with decreasing mean sulfate (SO 2− 4) deposition, with the magnitude of these relationships depending on plot deposition history. While the attribution of increasing trends in DOC to the reduction of SO 2− 4 deposi-tion could be confirmed in low to medium N deposition areas, in agreement with observations in surface waters, this was not the case in high N deposition areas. In conclusion, long-term trends of soil solution DOC reflected the interactions between controls acting at local (soil and vegetation properties) and regional (atmospheric deposition of SO 2− 4 and inorganic N) scales.

We identify, describe qualitatively, quantify biophysically and, if possible, monetarily valuate the most important ecosystem services in Swedish forests. Existing Swedish and Nordic research and statistics within this area are reviewed and used to develop a first framework for the valuation of ecosystem services in Swedish forests. We base our analysis on the CICES framework and the Cascade-model. Despite the rather long occurrence and use of the concept of ecosystem services, we do not yet have enough information on the status and economic value of services in Swedish forests. The value of the forest ecosystem services is at best an indication of the different multifunctional objectives that should be met in the management of the Swedish forests. The five most central ecosystem services in Swedish forests according to annual flow are timber and pulpwood, bioenergy, game, climate regulation and recreation and training, each estimated to have a monetary value of several billion SEK. The different ...

1. Climate change is a world-wide threat to biodiversity and ecosystem structure, functioning and services. To understand the underlying drivers and mechanisms, and to predict the consequences for nature and people, we urgently need better understanding of the direction and magnitude of climate change impacts across the soil–plant–atmosphere continuum. An increasing number of climate change studies are creating new opportunities for meaningful and high-quality generalizations and improved process understanding. However, significant challenges exist related to data availability and/or compatibility across studies, compromising opportunities for data re-use, synthesis and upscaling. Many of these challenges relate to a lack of an established ‘best practice’ for measuring key impacts and responses. This restrains our current understanding of complex processes and mechanisms in terrestrial ecosystems related to climate change. 2. To overcome these challenges, we collected best-practice methods emerging from major ecological research networks and experiments, as synthesized by 115 experts from across a wide range of scientific disciplines. Our handbook contains guidance on the selection of response variables for different purposes, protocols for standardized measurements of 66 such response variables and advice on data management. Specifically, we recommend a minimum subset of variables that should be collected in all climate change studies to allow data re-use and synthesis, and give guidance on additional variables critical for different types of synthesis and upscaling. The goal of this community effort is to facilitate awareness of the importance and broader application of standardized methods to promote data re-use, availability, compatibility and transparency. We envision improved research practices that will increase returns on investments in individual research projects, facilitate second-order research outputs and create opportunities for collaboration across scientific communities. Ultimately, this should significantly improve the quality and impact of the science, which is required to fulfil society's best practice, coordinated experiments, data management and documentation, ecosystem, experimental macroecology, methodology, open science, vegetation This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2019 The Authors. Methods in Ecology and Evolution published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Explaining the large-scale diversity of soil organisms that drive biogeochemical processes—and their responses to environmental change—is critical. However, identifying consistent drivers of belowground diversity and abundance for some soil organisms at large spatial scales remains problematic. Here we investigate a major guild, the ectomycorrhizal fungi, across European forests at a spatial scale and resolution that is—to our knowledge—unprecedented, to explore key biotic and abiotic predictors of ectomycorrhizal diversity and to identify dominant responses and thresholds for change across complex environmental gradients. We show the effect of 38 host, environment, climate and geographical variables on ectomycorrhizal diversity, and define thresholds of community change for key variables. We quantify host specificity and reveal plasticity in functional traits involved in soil foraging across gradients. We conclude that environmental and host factors explain most of the variation in ectomycorrhizal diversity, that the environmental thresholds used as major ecosystem assessment tools need adjustment and that the importance of belowground specificity and plasticity has previously been underappreciated.

Aim Macroclimate is a major determinant of large-scale diversity patterns. However, the influence of smaller-scale factors on local diversity across large spatial extents is not well documented. Here, we quantify the relative importance of local (patch-scale), landscape-scale and macroclimatic drivers of herbaceous species diversity in small forest patches in agricultural landscapes across Europe. Location Deciduous forest patches in eight regions along a macroclimatic gradient from southern France to central Sweden and Estonia. Methods The diversity of forest specialists and generalists at three levels (whole forest patch, sampling plots within patches and between scales) was related to patch-scale (forest area, age, abiotic and biotic heterogeneity), landscape-scale (amount of forest, grasslands and hedgerows around the patch, patch isolation) and macroclimatic variables (temperature and precipitation) using generalized linear mixed models and variation partitioning for each group of variables. Results The total amount of explained variation in diversity ranged from 8% for plot-scale diversity of generalists to 54% for patch-scale diversity of forest specialists. Patch-scale variables always explained more than 60% of the explained variation in diversity, mainly due to the positive effect of within-patch heterogeneity on patch-scale and between-scale diversities and to the positive effect of patch age on plot-scale diversity of forest specialists. Landscape-scale variables mainly contributed to the amount of explained variation in plot-scale diversity, being more important for forest specialists (21%) than for generalists (18%). Macroclimatic variables contributed a maximum of 11% to the plot-scale diversity of generalists. Main conclusions Macroclimate poorly predicts local diversity across Europe, and herbaceous diversity is mainly explained by habitat features, less so by landscape structure. We show the importance of conserving old forest patches as refugia for typical forest species, and of enhancing the landscape context around the patches by reducing the degree of disturbance caused by agriculture.

Atmospheric deposition to forests has been monitored within the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with sampling and analyses of bulk precipitation and throughfall at several hundred forested plots for more than 15 years. The current deposition of inorganic nitrogen (nitrate and ammonium) and sulphate is highest in central Europe as well as in some southern regions. We compared linear regression and Mann-Kendall trend analysis techniques often used to detect temporal trends in atmospheric deposition. The choice of method influenced the number of significant trends. Detection of trends was more powerful using monthly data compared to annual data. The slope of a trend needed to exceed a certain minimum in order to be detected despite the short-term variability of deposition. This variability could to a large extent be explained by meteorological processes, and the minimum slope of detectable trends was thus similar across sites and many ions. The overall decreasing trends for inorganic nitrogen and sulphate in the decade to 2010 were about 2% and 6%, respectively. Time series of about 10 and 6 years were required to detect significant trends in inorganic nitrogen and sulphate on a single plot. The strongest decreasing trends were observed in western central Europe in regions with relatively high deposition fluxes, whereas stable or slightly increasing deposition during the last 5 years was found east of the Alpine region as well as in northern Europe. Past reductions in anthropogenic emissions of both acidifying and eutrophying compounds can be confirmed due to the availability of long-term data series but further reductions are required to reduce deposition to European forests to levels below which significant harmful effects do not occur according to present knowledge. © 2014 The Authors.

The C:N ratio is considered as an indicator of nitrate leaching in response to high atmospheric nitrogen (N) deposition. However, the C:N ratio is influenced by a multitude of other site-related factors. This study aimed to unravel the factors determining C:N ratios of forest floor, mineral soil and peat top soils in more than 4000 plots of the ICP Forests large-scale monitoring network. The first objective was to quantify forest floor, mineral and peat soil C:N ratios across European forests. Secondly we determined the main factors explaining this C:N ratio using a boosted regression tree analysis (BRT), including fifteen site and environmental variables. Ninety-five percent of the C:N ratios were between 16 and 44 in the forest floor, between 13 and 44 in the peat topsoil and between 10 and 32 in the mineral topsoil. Within the aerated forest floor and the mineral soil, the C:N ratios decreased with depth, while in the hydromorphic forest floor and the peats no clear trend with depth was observed. Tree species was clearly the most important explanatory variable for the C:N ratio in both forest floors and topsoils, while it was soil type in the deeper mineral soil layers. The lowest C:N ratios both in the forest floor and the top mineral soil were found in black locust (Robinia pseudoacacia L.) and black alder (Alnus glutinosa L.) stands, both N fixing tree species. While in the forest floor the highest C:N ratios were found in evergreen species like pine, cork oak (Quercus suber L.) and eucalyptus, the pine species and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) showed the highest C:N ratios in the mineral soil. The second most important explanatory variable in the forest floor and mineral topsoil was the biogeographical zoning (ecoregion). In the peat topsoil and in the deeper mineral soil layers it was the humus type. Deposition and climatic variables were of minor importance at the European scale. Further analysis for eight main forest tree species individually, showed that the influence of environmental variables on C:N ratios was tree species dependent. For Aleppo pine (Pinus halepensis Miller) and holm oak (Quercus ilex L.), both with a typical Mediterranean distribution, the relationship between N and S deposition and C:N ratio appeared to be positive. This study suggests that applying C:N ratios as a general indicator of the N status in forests at the European level, without explicitly accounting for tree species, is too simplistic and may result in misleading conclusions.

Aim of study: The main aim of the work was to summarize availability, quality and comparability of on-going European Research and Monitoring Networks (ERMN), based on the results of a COST FP0903 Action questionnaire carried out in September 2010 and May 2012.Area of study: The COST Action FP0903 involves 29 European countries and 4 non-COST institutions from USA, Morocco and Tunisia. In this study, the total of 22 replies to the questionnaire from 18 countries were included.Materials and methods: Based on the feedback from the Action FP0903 countries, the most popular European Networks were identified. Thereafter, the access to the network database, available quality assurance/quality control procedures and publication were described. Finally, the so-called “Supersites” concept, defined as a “highly instrumented research infrastructure, for both research and monitoring of soil-plant-atmosphere interactions” was discussed.Main results: The result of the survey indicate that the vast majority of the Action FP0903 countries participate in the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forest (ICP Forest). The multi-disciplinary International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystems (ICPIM) is the second most widespread forest programme. Research highlights: To fully understand biochemical cycles in forest ecosystems, long-term monitoring is needed. Hence, a network of “Supersites”, is proposed. The application of the above infrastructure can be an effective way to attain a better integration of research and monitoring networks at forest sites in Europe.Keywords: Supersites; European Research Monitoring Networks; Harmonization; Forest.

Summary Land use change alters water and element cycles, but the changes in these cycles after conversion, for example, from cropland to forest are not fully described in hydrological and nutrient transport models, which usually describe either cropland or forest stands. In the European Union future afforestation is likely to occur on abandoned cropland, and evaluation of the future impacts of this land use change will require projections with models that include combined cropland-forest modules. This study used the agro-based DAISY model (Version 4.93) to investigate changes in the soil water balance over four decades following afforestation of a homogeneous area of former arable land on a sandy loam in Denmark. Hydrological data collected during nine hydrological years (April 2001–March 2010) were used to test the DAISY model. Monthly data on soil water content at 0–90 cm used for calibration were available from April 2001 to December 2002 for six monoculture stands of oak (age 8, 22 and 31 years) and Norway spruce (age 4, 13 and 32 years). Model performance was evaluated by considering uncertainties in model inputs using the Generalised Likelihood Uncertainty Estimation (GLUE) procedure. The GLUE estimates obtained (uncertainty bands 5% and 95%) agreed satisfactorily with measured monthly soil water content during the calibration period (April 2001–December 2002). Similarly, in the oldest oak stand, long-term monitoring observations and predictions of monthly water content were in satisfactory agreement during the period January 2003–March 2010). Sensitivity analysis showed that the DAISY model was most sensitive to the potential evapotranspiration factor and soil hydraulic parameters included in the Campbell model. Simulation results during nine hydrological years showed that 16–25% of incoming precipitation led to water recharge in the spruce stands, while the corresponding range for oak stands was 25–27%. A 35-year DAISY simulation revealed that Norway spruce consumed more water than oak, with differences in annual water recharge in the range 31–174 mm year−1 and with greater differences in rainy years (precipitation >900 mm year−1).

Change history: In the HTML version of this Article, author 'Filipa Cox' had no affiliation in the author list, although she was correctly associated with affiliation 3 in the PDF. In addition, the blue circles for 'oak' were missing from Extended Data Fig. 1. These errors have been corrected online.

The area of broadleaved forests is projected to increase in Denmark as well as in the rest of Europe. However, studies of the N leaching response to elevated N deposition have focused on coniferous stands and considerable uncertainty still remains on whether broadleaved and coniferous forests respond differently to elevated N. We studied N input–output relations for eight stands intensively monitored during 2002–2005 and literature data for 37 additional stands which together formed a comprehensive dataset on Danish forests including 26 broadleaved stands and 19 coniferous stands. Nitrate leaching was significantly higher in first generation stands on former arable land with mineral soil C/N ratios 10–15, but both low and high rates were observed independent of the N input. A net N loss was observed in some of these stands even though they are in the aggrading phase and accumulate N in the biomass. Broadleaved stands had significantly lower throughfall N deposition than coniferous stands and this seems to be the main process where forest type exerts an influence on the N cycle. Lower soil C/N ratios offset the effect of throughfall N deposition and thus N leaching did not differ between the two forest types. The best regression models for prediction of nitrate leaching included throughfall N deposition and C/N ratio, but only a minor part of the variability was explained. The C/N ratio of the upper mineral soil was more generally applicable than that of the organic layer. The N retention of the soil was reasonably well predicted above a C/N ratio of 25, but below this threshold the importance is not known. We suggest focusing future efforts on quantifying the relative retention functions (sink strength) of the vegetation and the soil organic matter to improve the predictions of N retention and N leaching.

The overall aim of the project was to study pregnant women's knowledge of danger signs during pregnancy and childbirth and actions taken in case danger signs occurred. Both quantitative and qualitative methods were used. A questionnaire was administered at the antenatal care clinic (ANC). Non-participant observations of the midwives at the ANC were also performed. Individual interviews were conducted with pregnant and newly delivered women as well as with clinical officers. A retrospective study of maternity records was also conducted. A majority of the women attended their first ANC visit late in the pregnancy. Women's general knowledge of danger signs was low. A lack of discrepancy between common pregnancy related and dangerous symptoms was noted. The observations revealed that little or no health education concerning danger signs were given and inadequate examination of the women were conducted. The ANC reaches around 92% off the pregnant women. This provides an ideal opportunity for information on danger signs and when and where to seek care. It is important to encourage early ANC attendance and complete examinations in order to identify high-risk pregnancies and prevent treatable illnesses.

Canopy litterfall is a significant pathway for return of nutrients and carbon (C) to the soil in forest ecosystems. Litterfall was studied in five even-aged stands of Norway spruce, Sitka spruce, Douglas-fir, European beech and common oak at three different locations in Denmark; two sandy sites, Ulborg and Lindet in Jutland, and one loamy site, Frederiksborg on Zealand. Litterfall was collected during three years from 1994 to 1996 in all five species and during six years from 1994 to 1999 in Norway spruce, Sitka spruce and European beech. The average total litterfall was in the range of 3200–3700 kg ha −1 yr −1 and did not differ significantly among tree species. There were no significant differences in total litterfall among sites during the short period, but during the longer period the richer site Frederiksborg had significantly higher total and foliar litterfall amounts compared to the more nutrient-poor sites Lindet and Ulborg. There were close relationships between foliar and total litterfall suggesting that foliar litterfall can be reliably estimated from total litterfall. Beech and oak bud scale litter was significantly related to foliar litterfall. The amount of branch and twig litter was significantly higher in oak than in other tree species. The average foliar litterfall was well related to the annual volume increment. The relationship differed markedly from previously reported relationships based on global litterfall data suggesting that such relationships are better evaluated at the regional level. Nutrient concentrations and fluxes in foliar litterfall were not significantly different among the five tree species. However, there was a significant effect of site on most nutrient concentrations of the three litterfall fractions, and foliar fluxes of P, Ca and Mn were all significantly highest at Frederiksborg and lowest at Ulborg. The similarity in litterfall inputs to the forest floor under these five tree species suggested that previous reports of large variability in forest floor accumulation should primarily be attributed to differences in litter decomposition.

En attente clé UT; International audience; In Europe, like in many temperate lowlands worldwide, forest has a long history of fragmentation and land use change. In many places, forest landscapes consist of patches of different quality, age, size and isolation, embedded in a more or less intensively managed agricultural matrix. As potential biodiversity islets, small forest patches (SFP) may deliver several crucial ecosystem services to human society, but they receive little attention compared to large, relatively intact forest patches. Beyond their role as a biodiversity reservoir, SFP provide important in situ services such as timber and wild food (game, edible plants and mushrooms) production. At the landscape scale, SFP may enhance the crop production via physical (obstacle against wind and floods) and biological (sources of pollinators and natural enemies) regulation, but may, on the other hand, also be involved in the spread of infectious diseases. Depending on their geographic location, SFP can also greatly influence the water cycle and contribute to supply high-quality water to agriculture and people. Globally, SFP are important carbon sinks and are involved in nutrient cycles, thus play a role in climate change mitigation. Cultural services are more related to landscape values than to SFP per se, but the latter may contribute to the construction of community identity. We conclude that SFP, as local biodiversity hotspots in degraded landscapes, have the potential to deliver a wide range of ecosystem services and may even be crucial for the ecological intensification of agro-ecosystems. There is thus an urgent need to increase our knowledge about the relationships between biodiversity and ecosystem services delivered by these SFP in agricultural landscapes.

The aim of this study was to evaluate the suitability of the (Ca + Mg + K)/Al and the Ca/Al ratios in soil solution as chemical criteria for forest condition in critical load calculations for forest ecosystems. The tree species Norway spruce, Sitka spruce and beech were studied in an area with high deposition of sea salt and nitrogen in the south-western part of Jutland, Denmark. Throughfall and soil water were collected monthly and analysed for pH, NO3-N, NH4-N, K, Ca, Mg, DOC and Altot. Organic Al was estimated using DOC concentrations. Increment and defoliation were determined annually, and foliar element concentrations were determined every other year. The throughfall deposition was highest in the Sitka spruce stand (maximum of 40 kg N ha−1yr−1) and lowest in the beech stand (maximum of 11 kg N ha−1yr−1). The Sitka spruce stand leached on average 12 kg N ha−1yr−1 during the period 1988–1997 and leaching increased throughout the period. Only small amounts of N were leached from the Norway spruce stand whereas almost no N was leached from the beech stand. For all tree species, both (Ca + Mg + K)/Al and Ca/Al ratios decreased in soil solution at 90 cm depth between 1989 and 1999, which was mainly caused by a decrease in concentrations of base cations. The toxic inorganic Al species were by far the most abundant Al species at 90 cm depth. At the end of the measurement period, the (Ca + Mg + K)/Al ratio was approximately 1 for all species while the Ca/Al ratio was approximately 0.2. The lack of a trend in the increment rates, a decrease in defoliation as well as sufficient levels of Mg and Ca in foliage suggested an unchanged or even slightly improved health condition, despite the decreasing and very low (Ca + Mg + K)/Al and Ca/Al ratios. The suitability of these soil solution element ratios is questioned as the chemical criteria for soil acidification under field conditions in areas with elevated deposition rates of sea salts, in particular Mg.

International audience; Key messageAtmospheric deposition of nitrogen compounds and soil and foliar variables related to N deposition resulted important factors accounting for the variability of defoliation in European forest plots.ContextNitrogen (N) deposition has increased in the northern hemisphere because of anthropogenic-related emission of N compounds. Increased N availability may have an adverse impact on forest sustainability.AimsThis study aims to test the importance of throughfall N (Nthr) deposition in explaining the variability of the frequency of trees with defoliation >25 % (F25), an indicator of forest condition.MethodsA pan-European data set (71 plots) with enhanced quality control was considered. The additive effect of Nthr-related predictors (identified conceptually and by rank correlation) in explaining F25 was investigated by partial least square regression in comparison with a reference model based on site, stand, management and climate data. Reported damage to foliage, Nthr deposition, foliar N ratios and mineral top-soil variables were added stepwise to the reference model.ResultsN-related variables improved defoliation models. Higher Nthr deposition led to higher F25 for beech and Norway spruce, while the effect was opposite for Scots pine. Higher foliar N ratios led to higher F25 for all species.ConclusionNthr deposition, damage to foliage, foliar N/P, N/Ca, N/Mg, N/K, top-soil pH, C/N and exchangeable base cation resulted important factors (although with possible diverse effect) in explaining the variability of F25 among plots.

The article argues for the importance of reconciling the institutions of representative government and network governance by means of a combined structure of ‘co-governance’, and the need for elected politicians in a role as co-governing guardians of democracy in network governance. Based on an examination of two different cases of interactive governance within the field of school reform at the local level in Denmark, some lessons are drawn as to an appropriate new role for elected politicians in a structure of co-governance.

Key message Exceedance of critical limits in soil solution samples was more frequent in intensively monitored forest plots across Europe with critical loads for acidity and eutrophication exceeded compared to other plots from the same network. Elevated inorganic nitrogen concentrations in soil solution tended to be related to less favourable nutritional status. Context Forests have been exposed to elevated atmospheric deposition of acidifying and eutrophying sulphur and nitrogen compounds for decades. Critical loads have been identified, below which damage due to acidification and eutrophication are not expected to occur. Aims We explored the relationship between the exceedance of critical loads and inorganic nitrogen concentration, the base cation to aluminium ratio in soil solutions, as well as the nutritional status of trees. Methods We used recent data describing deposition, elemental concentrations in soil solution and foliage, as well as the level of damage to foliage recorded at forest plots of the ICP Forests intensive monitoring network across Europe. Results Critical loads for inorganic nitrogen deposition were exceeded on about a third to half of the forest plots. Elevated inorganic nitrogen concentrations in soil solution occurred more frequently among these plots. Indications of nutrient imbalances, such as low magnesium concentration in foliage or discolouration of needles and leaves, were seldom but appeared more frequently on plots where the critical limits for soil solution were exceeded. Conclusion The findings support the hypothesis that elevated nitrogen and sulphur deposition can lead to imbalances in tree nutrition.

Assessing defoliation and measuring litterfall are two different ways of estimating the shedding of needles and leaves from the forest canopy. Both variables can be said to reflect the crown condition, but the two methods have rarely been compared. In this study the visual observations of defoliation of individual trees were compared with sampled litterfall data for the two main tree species in Denmark, Fagus sylvatica and Picea abies. Defoliation assessments and litterfall measurements were performed in seven level II plots. Six of the stands were 40 yrs old and the remaining stand was 81 yrs old. Both a positive and a negative correlation, which were not significant, were observed between defoliation and total leaf litterfall on the beech sites. Similarly, no significant correlation was observed between defoliation and the yearly needle litterfall on the younger Norway spruce plots. However, the defoliation and the yearly needle litterfall at the old stand at Klosterhede were positively correlated on a ...

In Europe, the combined effects of the global enrichment in atmospheric CO2 and the high atmospheric nitrogen (N) deposition have increased forest productivity during the last decades. Since N deposition is still high in many European regions and atmospheric CO2 is still rising, forest productivity in Europe could continue to increase. However, if nutrient availability becomes a limiting factor, forest productivity will not continue its increase, which will inevitably decrease the carbon sequestering capacity of European forests. The objectives of this study were to describe the nutritional status of the main European tree species, to identify growth limiting nutrients and to assess changes in tree nutrition during the past two decades. We analysed the foliar nutrition data collected during 1992-2009 on the intensive forest monitoring plots of the ICP Forests programme. This dataset is unique in its scope and size, and has the further advantage of being harmonized among all participating countries. Of the 22 significant temporal trends that were observed in foliar nutrient concentrations, 20 were decreasing and 2 were increasing. Altogether our results show a clear deterioration in P nutrition during the past two decades in some of the main tree species. Our study also highlights some downward trends that should be monitored closely in the future since they could become alarming: e.g. decrease in foliar S concentration in P. abies and P. sylvestris, in foliar Mg concentration in F. sylvatica, in foliar K concentration in Q. petraea and P. abies and in foliar Ca concentration in F. sylvatica and Q. petraea. Increased tree productivity, possibly resulting from high N deposition and from the global increase in atmospheric CO2, has led to higher nutrient demand by trees. Soil nutrient supply was however not always sufficient to meet the demand of faster growing trees. As tree nutrient status exerts a tight control on net ecosystem productivity, this deterioration in tree nutrition could have a strong impact on the response of forest ecosystems to climate change. Nutrient availability and tree nutrition should therefore be accounted for in global carbon cycle to allow climate models to better predict C sequestration capacity of forests and avoid overestimations. Our findings are totally in line with several recent global studies showing that the unbalanced inputs of C and N relative to P induced significant changes in organism stoichiometry resulting in profound and uncertain consequences on the structure, functioning and diversity of terrestrial and aquatic ecosystems.

(1997). The municipality between central state and local self‐government: Towards a new municipality. Local Government Studies: Vol. 23, No. 4, pp. 44-69.

Canopy throughfall was collected at four distances from the tree trunk and at six depths in the canopy of a Norway spruce forest at Klosterhede, Denmark. Forty-five series of throughfall were collected during the years 1992 and 1993. The samples were analyzed for pH, Na+, K+, Ca2+, Mg2+, NH4+, Cl−, NO3−, and SO42−. The smallest quantity of throughfall was sampled closest to the tree trunk, and the largest quantity of throughfall was sampled in the periphery of the canopy at all levels in the canopy. The quantity of throughfall was highest at the top of the tree and decreased down through the canopy. The highest fluxes of all ions were observed close to the tree trunk, and the fluxes decreased as a function of the distance from the nearest tree trunk. The lowest fluxes were observed in the upper canopy, and they increased down through the canopy. A negative net throughfall of NH4+ indicated an uptake of NH4+ in the canopy in the growing season. The measurements also indicated an uptake of NO3− at some positions in the canopy, but only during the growing season. The uptake of NH4+ was negatively correlated to the fluxes of NH4+ in precipitation. Leaching of K+, Ca2+, and Mg2+ was accumulated to be highest in the lower canopy. Potassium was leached in larger amounts than Ca2+, which again was leached in a greater amount than Mg2+. Potassium leached from the trees in large amounts even during the dormant season.

Of a wide variety of international forest research and monitoring networks, several networks are dedicated to the effects of climate change on forests, while the effects of anthropogenic pollutants on forests have been a major area for both monitoring and research for decades. The large amounts of data already obtained within existing monitoring programmes and large-scale international projects can be used to increase understanding of the state and potential of forest mitigation and adaptation to climate change in a polluted environment, and a major challenge now is to evaluate and integrate the presently available databases. We present a meta-database with the main goal to highlight available data and integrate the information about research and monitoring of selected European Research and Monitoring Networks (ERMNs). Depending on the selected ERMNs, the list of variables and the measurement units differ widely in the databases. As a result, activities related to the identification, evaluation and integration of the presently available databases are important for the scientific community. Furthermore, and equally important, the recognition of current knowledge gaps and future needed research is made easier. This analysis suggests that: ground-level ozone is under-investigated, although it is one of the pollutants of greatest concern to forests; in addition to CO2, long-term other greenhouse gasses (GHG) flux measurements should be carried out; there is still a need of improving links between monitoring of atmospheric changes and impacts on forests; research-oriented manipulative experiments in the forests are missing.

Water and nutrient supply to forest trees are major factors controlling tree growth and forest vitality. Therefore, changes in the supply of water and nutrients to the trees may be important contributing reasons to the forest damages observed in Europe. Such changes may be caused by several factors, e.g. air pollution, soil acidification and climate change. The present study investigates possible effects on tree growth, growth related parameters and nutrition related to changes in the water and nutrient supply. Water and nutrient supply to the forest soil was manipulated in three roof covered plots. The treatments consisted of 1) summer drought, 2) irrigation and 3) combined irrigation and fertilizer application (fertigation). The results from the roof covered treatment plots were compared to a control plot without roof. Increased supply of water during the spring and early summer increased the diameter growth, whereas application of nutrients in addition to irrigation had no additional effect on tree growth. Addition of nutrients increased the needle content of P, Mn, Ca and Mg. Extended summer drought for 2 months had no effect on the tree growth or other growth parameters, but drought reduced the root development in the upper soil layer. Furthermore, drought induced significant stress symptoms by increasing the cone shredding substantially

Atmospheric deposition of acidifying compounds (e.g. S), nitrogen (N) as a nutrient and base cations (e.g. Ca) to forests is a major driver for many processes in forests. In Europe, various measures have been taken to reduce S and N deposition since the late 1980ties. Trend analyses are regularly performed based on measurement in open field by EMEP and in forests by ICPForests. However, various trend analyses techniques are in use. In this study the trends of bulk and throughfall N and S deposition on ICP-Forests level II sites have been investigated. Sulphur deposition showed a decreasing trend from 2001 to 2010 that has been identified to be significant for the majority of the about 50 sites with continuous data (linear regression, 95% sign. Level). The mean thoughfall of theses sites decreased from about 12 kg S ha-1 a-1 in 2001 to about 6 kg S ha-1 a-1 (about 6% a-1). For N this value decreased from about 15 kg N ha-1 a-1 to about 12 kg N ha-1 a-1 (about 2.5% a-1), however, decreasing trends were identified to be significant for much fewer sites. In order to estimate the minimal detectable trend, p-values were plotted against the relative slope. Most p-values were in a similar bell-shaped band for time series with the same length for most ions. For time series with 10 years S deposition data, the band falls below 0.05 at relative slope larger than about 3% a-1. With 6 years of data, relative slopes need to be larger to reliably attain p

Summary • Nitrogen (N) availability is known to influence ectomycorrhizal fungal components, such as fungal community composition, biomass of root tips and production of mycelia, but effects have never been demonstrated within the same forest. • We measured concurrently the abundance of ectomycorrhizal root tips and the production of external mycelia, and explored the changes in the ectomycorrhizal community composition, across a stand-scale N deposition gradient (from 27 to 43 kg N ha )1 yr )1 ) at the edge of a spruce forest. The N status was affected along the gradient as shown by a range of N availability indices. • Ectomycorrhizal root tip abundance and mycelial production decreased five and 10-fold, respectively, with increasing N deposition. In addition, the ectomycorrhizal fungal community changed and the species richness decreased. The changes were correlated with the measured indices of N status, in particular N deposition and N leaching. • The relationship between the altered ectomycorrhizal community, root tip abundance and mycelial production is discussed in the context of the N parameters. We suggest that increased N deposition to forests will cause large changes in ectomycorrhizal fungal community structure and functioning, which, in turn, may result in reduced N uptake by roots and fungi, and increased losses of N by leaching.

Canopy throughfall was collected sequentially during individual rain events in a Norway spruce stand at Klosterhede in Denmark (1989) and a Douglas-fir stand at Speuld in the Netherlands (1993). Simultaneously, precipitation was sampled sequentially. Each fraction was analyzed for pH, Na + , K + , Ca 2+ , Mg 2+ , NH 4 + , Cl − , NO 3 , and SO 4 2− . Analysis of successive precipitation collected at both sites generally showed the highest concentrations of Na + , Cl − , Mg 2+ , Ca 2+ , NO 3 − , and SO 4 2− in the initial fraction of most rain events followed by decreasing ion concentrations in subsequent samples. For K + , and especially for NH 4 + , several concentration maxima were observed throughout the events. At Speuld, the sequential throughfall showed a slight increase in concentration in the beginning, followed by a continuous decrease. At the end of the events, concentrations of throughfall increased again. At Klosterhede, decreasing ion concentrations of all ions were observed throughout some events, while constant and even increasing ion concentrations were seen throughout others. The ion concentrations in throughfall were inversely connected to the intensity of the throughfall. At both sites, the concentrations in throughfall in the final part of the event never reached a constant value and were always higher than in the simultaneously collected rain water. This indicates that the sources for the ions in throughfall were never emptied. The gradual and steadily changing concentration curves suggest that the processes involved in dry deposition and canopy exchange are slow. It was further found that the concentrations of NH 4 + and SO 4 2− in the initial throughfall at Speuld sometimes exceeded concentrations which could damage plant tissues.

Climatic changes, including altered precipitation regimes, will affect key ecosystem processes, such as plant productivity and biodiversity for many terrestrial ecosystems. Past and ongoing precipitation experiments have been conducted to quantify these potential changes. An analysis of these experiments indicates that they have provided important information on how water regulates ecosystem processes. However, they do not adequately represent global biomes nor forecasted precipitation scenarios and their potential contribution to advance our understanding of ecosystem responses to precipitation changes is therefore limited, as is their potential value for the development and testing of ecosystem models. This highlights the need for new precipitation experiments in biomes and ambient climatic conditions hitherto poorly studied applying relevant complex scenarios including changes in precipitation frequency and amplitude, seasonality, extremity and interactions with other global change drivers. A systematic and holistic approach to investigate how soil and plant community characteristics change with altered precipitation regimes and the consequent effects on ecosystem processes and functioning within these experiments will greatly increase their value to the climate change and ecosystem research communities. Experiments should specifically test how changes in precipitation leading to exceedance of biological thresholds affect ecosystem resilience and acclimation.

Riparian forests (RF) growing along streams, rivers and lakes comprise more than 2% of the forest area in the Nordic countries (considering a 10 m wide zone from the water body). They have special ecological functions in the landscape. They receive water and nutrients from the upslope areas, are important habitats for biodiversity, have large soil carbon stores, but may emit more greenhouse gases (GHG) than the uplands. In this article, we present a review of the environmental services related to water protection, terrestrial biodiversity, carbon storage and greenhouse gas dynamics provided by RF in the Nordic countries. We discuss the benefits and trade-offs when leaving the RF as a buffer against the impacts from upland forest management, in particular the impacts of clear cutting. Forest buffers are effective in protecting water quality and aquatic life, and have positive effects on terrestrial biodiversity, particularly when broader than 40 m, whereas the effect on the greenhouse gas exchange is unclear.

International audience; Fertilisation of agricultural land causes an accumulation of nutrients in the top soil layer, among which phosphorus (P) is particularly persistent. Changing land use from farmland to forest affects soil properties, but changes in P pools have rarely been studied despite their importance to forest ecosystem development. Here, we describe the redistributions of the P pools in a four-decadal chronosequence of post-agricultural common oak (Quercus robur L.) forests in Belgium and Denmark. The aim was to assess whether forest age causes a repartitioning of P throughout the various soil P pools (labile P, slowly cycling P and occluded P); in particular, we addressed the time-related alterations in the inorganic versus organic P fractions. In less than 40 years of oak forest development, significant redistributions have occurred between different P fractions. While both the labile and the slowly cycling inorganic P fractions significantly decreased with forest age, the organic fractions significantly increased. The labile P pool (inorganic + organic), which is considered to be the pool of P most likely to contribute to plant-available P, significantly decreased with forest age (from >20 to

Precipitation, throughfall and soil moisture were measured, and interception, transpiration and water recharge were estimated in four afforestation chronosequences on former arable land at two Danish locations (Vestskoven and Gejlvang) and at one southern Swedish location (Tonnersjoheden). Afforestation was performed using Norway spruce ( Picea abies (Karst.) L.) and common oak ( Quercus robur L.) at Vestskoven and only Norway spruce at Gejlvang and Tonnersjoheden. Four to five stands of different ages (5–92 years) were studied in each of these chronosequences. Hydrological fluxes were calculated using the soil hydrological model SWAP. Throughfall flux and soil water content were used for calibration of the model. The simulated water recharge decreased with increased stand age within 30–40 years of afforestation. This was mainly due to increased interception evaporation with age. The annual water recharge was higher below oak stands (149–192 mm yr −1 ) than below spruce stands (107–191 mm yr −1 ) of similar age. The relative water recharge was also considerably higher from the sandy glaciofluvial soils at Gejlvang and Tonnersjoheden than from the sandy loamy till soils at Vestskoven.

The validity of porous cup soil water samplers to extract soil solutions is most often evaluated in short-term laboratory studies. Such laboratory studies differ significantly from the situation in the field. Therefore the aim of the present study was to compare ceramic and PTFE porous cup soil water samplers under natural conditions in a long-term field experiment. Soil solutions were sampled from two depths (E, horizon and BC horizon) in an acidified, sandy forest soil in Denmark. Taking the spatial variability of the forest into account, the mean concentrations of base cations, S042-, Cl-, H+, and nonpurgeable organic carbon (NPOC) obtained with the two sampler types are compared. In most cases the concentrations of solutes and NF’OC in the PTFE cups were higher than the concentrations in the ceramic cups. The differences in mean concentrations of K+, Mg2+, Na+, Cl-, S042-, and NO, obtained with the two samplers were generally within the variability of the PTFE samplers whereas the concentrations of Ca2+, H+, and NPOC obtained with the PTFE samplers were significantly higher than those obtained with the ceramic samplers. The difference in NPOC in the E, horizon is concluded to be caused by filtering. The difference in Ca2+ may to some extent be ascribed to dissolution of “glass pellets” in the PTFE sampler matrix, whereas the difference in H+ concentration between the sampler types remains unexplained.

The current landscapes in north-western Europe are the result of natural processes and human-induced land use and land use changes. Whereas during past centuries, the natural ancient forest cover disappeared and was -sometimes abruptly- converted in intensively used cultural landscapes, an opposed trend has become apparent recently. This trend reversal is at least partly related to the decision of the European Union and several of its member states to actively promote afforestation of -mainly- farmland, in order to respond to surplus agricultural production and to contribute to the international efforts to reduce the nitrate pollution of water bodies and the emission of greenhouse gases. However, many questions pertain regarding the implementation and evaluation of environmental effectiveness and efficiency of this afforestation policy.

There is limited knowledge of the contribution of afforested arable land to mitigation of greenhouse effects. In the AFFOREST project we evaluated the rate and magnitude of carbon (C) sequestration in biomass and soils following afforestation of cropland. Two oak (Quercus robur) and four Norway spruce (Picea abies) afforestation chronosequences (age range 1 to 90 years) were studied with respect to C sequestration in Denmark, Sweden and the Netherlands.

Knowledge on the impact of afforestation of arable land on N deposition and leaching of nitrate to groundwater and surface waters is limited. In the AFFOREST project we evaluated nitrogen (N) deposition and nitrate leaching following afforestation of cropland. Two oak (Quercus robur) and four Norway spruce (Picea abies) afforestation chronosequences (age range 1 to 90 years) were studied with respect to deposition and nitrate leaching in Denmark, Sweden and the Netherlands. This paper presents a synthesis of these six chronosequence experiments. Three to six forest stands of Norway spruce and/or common oak were monitored in each chronosequence for a period of two years. In each stand, throughfall and soil solutions beneath the root zone were sampled and nitrate leaching was calculated. For all sites and tree species, the throughfall deposition of N increased with stand height (and age). The forests varied substantially in their ability to retain N in the ecosystem. No consistent pattern was apparent in the three countries. However, in some chronosequences nitrate leaching was low or negligible in the early phase of afforestation and increased after canopy closure (> 15-20 years). In general, nutrient-rich clayey soils leached more nitrate than nutrient-poor sandy soils. In the first approximate 35 years after afforestation, nitrate leaching below the root zone was generally higher below oak than below Norway spruce. The presented results are compared to available studies and discussed.