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The new European Green Deal has the ambition to make the European Union the first climate-neutral continent by 2050. The European Commission presented an ambitious package of measures within the Biodiversity Strategy 2030, the Farm to Fork and the European Climate Law including actions to protect our soils. The Farm to Fork strategy addresses soil pollution with 50 % reduction in use of chemical pesticides by 2030 and aims 20 % reduction in fertilizer use plus a decrease of nutrient losses by at least 50%. The Biodiversity Strategy has the ambition to set a minimum of 30 % of the EU’s land area as protected areas, limit urban sprawl, reduce the pesticides risk, bring back at least 10 % of agricultural area under high-diversity landscape features, put forward the 25 % of the EU’s agricultural land as organically farmed, progress in the remediation of contaminated sites, reduce land degradation and plant more than three billion new trees. The maintenance of wetlands and the enhancement of soil organic carbon are also addressed in the European Climate Law. The new EU Soil Observatory will be collecting policy relevant data and developing indicators for the regular assessment and progress towards the ambitious targets of the Green Deal.

https://www.sciencedirect.com/science/article/pii/S0264837720304257

In recent years, forest fires have increased in terms of frequency, extent and intensity, especially in Mediterranean countries. Climate characteristics and anthropogenic disturbances lead forest environments to display high vulnerability to wildfires, with their sustainability being threatened by the loss of vegetation, changes on soil properties, and increased soil loss rates. Moreover, wildfires are a great threat to property and human life, especially in Wildland-Urban Interface (WUI) areas. In light of the impacts and trends mentioned above, this study aims to assess the impact of the Mati, Attika wildfire on soil erosion. The event caused 102 fatalities, inducing severe consequences to the local infrastructure network; economy; and natural resources. As such, the Revised Universal Soil Loss Equation (RUSLE) was implemented (pre-; post-fire) at the Rafina, Attika watershed encompassing the Mati WUI. Fire severity was evaluated based on the Normalized Burn Ratio (NBR). This index was developed utilizing innovative remotely sensed Earth Observation data (Sentinel-2). The high post-fire values indicate the fire's devastating effects on vegetation loss and soil erosion. A critical “update” was also made to the CORINE Land Cover (CLC) v. 2018, by introducing a new land use class namely “Urban Forest”, in order to distinguish the WUI configuration. Post-fire erosion rates are notably higher throughout the study area (4.53–5.98 t ha−1 y−1), and especially within the WUI zone (3.75–18.58 t ha−1 y−1), while newly developed and highly vulnerable cites now occupy the greater Mati area. Furthermore, archive satellite data (Landsat-5) revealed how the repeated (historical) wildfires have ultimately impacted vegetation recovery and erosional processes. To our knowledge this is the first time that RUSLE is used to simulate soil erosion at a WUI after a fire event, at least at a Mediterranean basin. The realistic results attest that the model can perform well at such diverse conditions, providing a solid basis for soil loss estimation and identification of high-risk erosion areas.

https://www.sciencedirect.com/science/article/pii/S034181621930462X

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts of most land plants. They have great ecological and economic impacts as they support plant nutrition and water supply, soil structure, and plant resistance to pathogens. Investigating AMF presence and distribution at small and large scales is critical. Therefore, research requires standard protocols to be easily implemented. In this chapter, we describe a workflow for AMF identification by high-throughput sequencing through Illumina MiSeq platform of two DNA target regions: small subunit (SSU) and internal transcribed spacer (ITS). The protocol can apply to both soil and root AMF communities.

https://link.springer.com/protocol/10.1007%2F978-1-0716-0603-2_9

This study presents the updated version of the recently published LANDUM model [Land Use Policy 48, 38–50 (2015)]. LANDUM is integrated into the 100 m resolution RUSLE-based pan-European soil erosion risk modelling platform of the European Commission. It estimates the effects of local land use and management practices on the magnitude of soil erosion across each NUTS2 region of the European Union. This is done based on a spatially explicit estimation of the so-called cover-management factor of (R)USLE family models which is also known as C-factor. In this updated version, the data on soil conservation measures (i.e., reduced tillage, cover crops and plant residues) reported in the latest EU Farm Structure Survey (2016) were integrated and elaborated in LANDUM in order to estimate the changes of the C-factor in Europe between 2010 and 2016. For 2016, a C-factor of 0.2316 for the arable land of the 28 Member States of the European Union was estimated. This implies an overall decrease of C-factor of ca. -0.84 % compared to the 2010 survey. The change in C-factor from 2010 to 2016 could be an indication for the effectiveness of Common Agricultural Policy (CAP) soil conservation measures in reducing soil erosion in Europe, especially key CAP policies such as Good Agricultural and Environmental Conditions and Greening.

https://www.sciencedirect.com/science/article/pii/S026483771931172X

Cover crops (CC) promote the accumulation of soil organic carbon (SOC), which provides multiple benefits to agro‐ecosystems. However, additional nitrogen (N) inputs into the soil could offset the CO2 mitigation potential due to increasing N2O emissions. Integrated management approaches use organic and synthetic fertilizers to maximize yields while minimizing impacts by crop sequencing adapted to local conditions. The goal of this work was to test whether integrated management, centered on CC adoption, has the potential to maximize SOC stocks without increasing the soil greenhouse gas (GHG) net flux and other agro‐environmental impacts such as nitrate leaching. To this purpose, we ran the DayCent bio‐geochemistry model on 8,554 soil sampling locations across the European Union. We found that soil N2O emissions could be limited with simple crop sequencing rules, such as switching from leguminous to grass CC when the GHG flux was positive (source). Additional reductions of synthetic fertilizers applications are possible through better accounting for N available in green manures and from mineralization of soil reservoirs while maintaining cash crop yields. Therefore, our results suggest that a CC integrated management approach can maximize the agro‐environmental performance of cropping systems while reducing environmental trade‐offs.

Soil erosion is a major global soil degradation threat to land, freshwater, and oceans. Wind and water are the major drivers, with water erosion over land being the focus of this work; excluding gullying and river bank erosion. Improving knowledge of the probable future rates of soil erosion, accelerated by human activity, is important both for policy makers engaged in land use decision-making and for earth-system modelers seeking to reduce uncertainty on global predictions. Here we predict future rates of erosion by modeling change in potential global soil erosion by water using three alternative (2.6, 4.5, and 8.5) Shared Socioeconomic Pathway and Representative Concentration Pathway (SSP-RCP) scenarios. Global predictions rely on a high spatial resolution Revised Universal Soil Loss Equation (RUSLE)-based semiempirical modeling approach (GloSEM). The baseline model (2015) predicts global potential soil erosion rates of 43+9.2−7 Pg yr−1, with current conservation agriculture (CA) practices estimated to reduce this by ∼5%. Our future scenarios suggest that socioeconomic developments impacting land use will either decrease (SSP1-RCP2.6–10%) or increase (SSP2-RCP4.5 +2%, SSP5-RCP8.5 +10%) water erosion by 2070. Climate projections, for all global dynamics scenarios, indicate a trend, moving toward a more vigorous hydrological cycle, which could increase global water erosion (+30 to +66%). Accepting some degrees of uncertainty, our findings provide insights into how possible future socioeconomic development will affect soil erosion by water using a globally consistent approach. This preliminary evidence seeks to inform efforts such as those of the United Nations to assess global soil erosion and inform decision makers developing national strategies for soil conservation.

https://www.pnas.org/content/117/36/21994

Soils harbor a substantial fraction of the world’s biodiversity, contributing to many crucial ecosystem functions. It is thus essential to identify general macroecological patterns related to the distribution and functioning of soil organisms to support their conservation and consideration by governance. These macroecological analyses need to represent the diversity of environmental conditions that can be found worldwide. Here we identify and characterize existing environmental gaps in soil taxa and ecosystem functioning data across soil macroecological studies and 17,186 sampling sites across the globe. These data gaps include important spatial, environmental, taxonomic, and functional gaps, and an almost complete absence of temporally explicit data. We also identify the limitations of soil macroecological studies to explore general patterns in soil biodiversity-ecosystem functioning relationships, with only 0.3% of all sampling sites having both information about biodiversity and function, although with different taxonomic groups and functions at each site. Based on this information, we provide clear priorities to support and expand soil macroecological research.

https://www.nature.com/articles/s41467-020-17688-2

The sampling method is a key aspect when designing a soil monitoring network. The determination of any physical and chemical property can be subject to uncertainties because of the sampling method. In this study, we compared the efficiency of sampling with a spade and a gouge auger for the physicochemical characterization of topsoil samples from 150 mineral soils under various land cover (LC) classes in Switzerland taken within the LUCAS 2015 Survey. The sampling methods differed in their scheme, accuracy of litter removal and control of sampling depth, which were more rigorous with the gouge auger than the spade method. Values of root mean square error of properties ranged between 1/2 and 1/30 of their mean values. Lin's concordance correlation coefficient showed that the spade and gouge auger methods produced similar results for all properties (LCCC ≥0.73), with a better relation for arable land than other LC classes. A poor relation was observed for potassium (LCCC = 0.35) in coniferous forest because of its shallow distribution in depth. We concluded that the simpler and cheaper spade method is an accurate method for topsoil sampling at the continental scale. From this study, it is clear that some improvements in the control of sampling depth and the accuracy of litter removal are needed, especially when monitoring forest soils and properties that change rapidly with depth. Spade sampling can help to expand the implementation of soil monitoring surveys at the continental scale at relatively low sampling cost.

https://onlinelibrary.wiley.com/doi/full/10.1111/ejss.12862

The occurrence of hydrological extremes in the Amazon region and the associated sediment loss during rainfall events are key features in the global climate system. Climate extremes alter the sediment and carbon balance but the ecological consequences of such changes are poorly understood in this region. With the aim of examining the interactions between precipitation and landscape-scale controls of sediment export from the Amazon basin, we developed a parsimonious hydro-climatological model on a multi-year series (1997–2014) of sediment discharge data taken at the outlet of Óbidos (Brazil) watershed (the narrowest and swiftest part of the Amazon River). The calibrated model (correlation coefficient equal to 0.84) captured the sediment load variability of an independent dataset from a different watershed (the Magdalena River basin), and performed better than three alternative approaches. Our model captured the interdecadal variability and the long-term patterns of sediment export. In our reconstruction of yearly sediment discharge over 1859–2014, we observed that landscape erosion changes are mostly induced by single storm events, and result from coupled effects of droughts and storms over long time scales. By quantifying temporal variations in the sediment produced by weathering, this analysis enables a new understanding of the linkage between climate forcing and river response, which drives sediment dynamics in the Amazon basin.

https://www.mdpi.com/2073-4433/11/2/208

The world's largest afforestation programs implemented by China made a great contribution to the global “greening up.” These programs have received worldwide attention due to its contribution toward achieving the United Nations Sustainable Development Goals. However, emerging studies have suggested that these campaigns, when not properly implemented, resulted in unintended ecological and water security concerns at the regional scale. While mounting evidence shows that afforestation causes substantial reduction in water yield at the watershed scale, process‐based studies on how forest plantations alter the partitioning of rainwater and affect water balance components in natural vegetation are still lacking at the plot scale. This lack of science‐based data prevents a comprehensive understanding of forest‐related ecosystem services such as soil conservation and water supply under climate change. The present study represents the first “Paired Plot” study of the water balance of afforestation on the Loess Plateau. We investigate the effects of forest structure and environmental factors on the full water cycle in a typical multilayer plantation forest composed of black locust, one of the most popular tree species for plantations worldwide. We measure the ecohydrological components of a black locust versus natural grassland on adjacent sites. The startling finding of this study is that, contrary to the general belief, the understory—instead of the overstory—was the main water consumer in this plantation. Moreover, there is a strict physiological regulation of forest transpiration. In contrast to grassland, annual seepage under the forest was minor in years with an average rainfall. We conclude that global long‐term greening efforts in drylands require careful ecohydrologic evaluation so that green and blue water trade‐offs are properly addressed. This is especially important for reforestation‐based watershed land management, that aims at carbon sequestration in mitigating climate change while maintaining regional water security, to be effective on a large scale.

https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14875

Soil phosphorus (P) loss from agricultural systems will limit food and feed production in the future. Here, we combine spatially distributed global soil erosion estimates (only considering sheet and rill erosion by water) with spatially distributed global P content for cropland soils to assess global soil P loss. The world’s soils are currently being depleted in P in spite of high chemical fertilizer input. Africa (not being able to afford the high costs of chemical fertilizer) as well as South America (due to non-efficient organic P management) and Eastern Europe (for a combination of the two previous reasons) have the highest P depletion rates. In a future world, with an assumed absolute shortage of mineral P fertilizer, agricultural soils worldwide will be depleted by between 4–19 kg ha−1 yr−1, with average losses of P due to erosion by water contributing over 50% of total P losses.

https://www.nature.com/articles/s41467-020-18326-7

https://www.nature.com/articles/s41893-020-0477-x

Fifty paired plots under simulated rainfall showed that the use of a cover of straw mulch of 50% (1 mg ha−1) in olive orchards results in a reduction of soil erosion. An economic survey based on interviews shows that the use of straw mulch in olive plantation would cost €174.7 ha−1, from which €54.7 ha−1 is needed for the application work, €52.3 ha−1 for the purchase cost, and €67.7 ha−1 for the transport of 20‐kg bales. The cost of the straw is 22.5% of the total income of the farmers. We found that their perception was negative about the use of straw mulch, as the tradition is to keep the soil clean from any weed or cover, except the crop. However, farmers would use it if they would be subsidized with a minimum of €267 ha−1, which is €92 ha−1 more than the costs estimated on the basis of the surveys. We conclude that soil erosion can be controlled with the use of straw mulch but that to convince farmers to adopt this management strategy, it needs to be subsidized.

Soil erosion is one of the eight threats in the Soil Thematic Strategy, the main policy instrument dedicated to soil protection in the European Union (EU). During the last decade, soil erosion indicators have been included in monitoring the performance of the Common Agricultural Policy (CAP) and the progress towards the Sustainable Development Goals (SDGs). This study comes five years after the assessment of soil loss by water erosion in the EU [Environmental science & policy 54, 438–447 (2015)], where a soil erosion modelling baseline for 2010 was developed. Here, we present an update of the EU assessment of soil loss by water erosion for the year 2016. The estimated long-term average erosion rate decreased by 0.4% between 2010 and 2016. This small decrease of soil loss was due to a limited increase of applied soil conservation practices and land cover change observed at the EU level. The modelling results suggest that, currently, ca. 25% of the EU land has erosion rates higher than the recommended sustainable threshold (2 t ha⁻¹ yr⁻¹) and more than 6% of agricultural lands suffer from severe erosion (11 t ha⁻¹ yr⁻¹). The results suggest that a more incisive set of measures of soil conservation is needed to mitigate soil erosion across the EU. However, targeted measures are recommendable at regional and national level as soil erosion trends are diverse between countries which show heterogeneous application of conservation practices.

https://www.mdpi.com/2072-4292/12/9/1365

Gully erosion may cause considerable soil losses and produce large volumes of sediment. The aim of this study was to perform a preliminary assessment on the presence of ephemeral gullies in Greece by sampling representative cultivated fields in 100 sites randomly distributed throughout the country. The almost 30-ha sampling surfaces were examined with visual interpretation of multi-temporal imagery from the online Google Earth for the period 2002–2019. In parallel, rill and sheet erosion signs, land uses, and presence of terraces and other anti-erosion features, were recorded within every sample. One hundred fifty-three ephemeral gullies were identified in total, inside 22 examined agricultural surfaces. The mean length of the gullies was 55.6 m, with an average slope degree of 9.7%. Vineyards showed the largest proportion of gullies followed by olive groves and arable land, while pastures exhibited limited presence of gullies. Spatial clusters of high gully severity were observed in the north and east of the country. In 77% of the surfaces with gullies, there were no terraces, although most of these surfaces were situated in slopes higher than 8%. It was the first time to use visual interpretation with Google Earth image time-series on a country scale producing a gully erosion inventory. Soil conservation practices such as contour farming and terraces could mitigate the risk of gully erosion in agricultural areas

https://www.mdpi.com/2073-4441/12/2/603

Global nuclear weapon testing and the Chernobyl accident have released large amounts of radionuclides into the environment. However, to date, the spatial patterns of these fallout sources remain poorly constrained. Fallout radionuclides (137Cs, 239Pu, 240Pu) were measured in soil samples (n = 160) collected at flat, undisturbed grasslands in Western Europe in the framework of a harmonised European soil survey. We show that both fallout sources left a specific radionuclide imprint in European soils. Accordingly, we used plutonium to quantify contributions of global versus Chernobyl fallout to 137Cs found in European soils. Spatial prediction models allowed for a first assessment of the global versus Chernobyl fallout pattern across national boundaries. Understanding the magnitude of these fallout sources is crucial not only to establish a baseline in case of future radionuclide fallout but also to define a baseline for geomorphological reconstructions of soil redistribution due to soil erosion processes.

https://www.nature.com/articles/s41598-020-68736-2

https://www.sciencedirect.com/science/article/pii/S0013935120303947

Land degradation by water and wind erosion is a serious problem worldwide. Despite the significant amount of research on this topic, quantifying these processes at large- or regional-scale remains difficult. Furthermore, very few studies provide integrated assessments of land susceptibility to both water and wind erosion. Therefore, this study investigated the spatial patterns of water and wind erosion risks, first separately and then combined, in the drought-prone region of East Africa using the best available datasets. As to water erosion, we adopted the spatially distributed version of the Revised Universal Soil Loss Equation and compared our estimates with plot-scale measurements and watershed sediment yield (SY) data. The order of magnitude of our soil loss estimates by water erosion is within the range of measured plot-scale data. Moreover, despite the fact that SY integrates different soil erosion and sediment deposition processes within watersheds, we observed a strong correlation of SY with our estimated soil loss rates (r2 = 0.4). For wind erosion, we developed a wind erosion index by integrating five relevant factors using fuzzy logic technique. We compared this index with estimates of the frequency of dust storms, derived from long-term Sea-Viewing Wide Field-of-View Sensor Level-3 daily data. This comparison revealed an overall accuracy of 70%. According to our estimates, mean annual gross soil loss by water erosion amounts to 4 billion t, with a mean soil loss rate of 6.3 t ha−1 yr−1, of which ca. 50% was found to originate in Ethiopia. In terms of land cover, ca. 50% of the soil loss by water erosion originates from cropland (with a mean soil loss rate of 18.4 t ha−1 yr−1), which covers ca. 15% of the total area in the study region. Model results showed that nearly 10% of the East Africa region is subject to moderate or elevated water erosion risks (>10 t ha−1 yr−1). With respect to wind erosion, we estimated that around 25% of the study area is experiencing moderate or elevated wind erosion risks (equivalent to a frequency of dust storms >45 days yr−1), of which Sudan and Somalia (which are dominated by bare/sparse vegetation cover) have the largest share (ca. 90%). In total, an estimated 8 million ha is exposed to moderate or elevated risks of soil erosion by both water and wind. The results of this study provide new insights on the spatial patterns of water and wind erosion risks in East Africa and can be used to prioritize areas where further investigations are needed and where remedial actions should be implemented.

https://www.sciencedirect.com/science/article/pii/S0048969719350089

Soils harbor a substantial fraction of the world’s biodiversity, contributing to many crucial ecosystem functions. It is thus essential to identify general macroecological patterns related to the distribution and functioning of soil organisms to support their conservation and consideration by governance. These macroecological analyses need to represent the diversity of environmental conditions that can be found worldwide. Here we identify and characterize existing environmental gaps in soil taxa and ecosystem functioning data across soil macroecological studies and 17,186 sampling sites across the globe. These data gaps include important spatial, environmental, taxonomic, and functional gaps, and an almost complete absence of temporally explicit data. We also identify the limitations of soil macroecological studies to explore general patterns in soil biodiversity-ecosystem functioning relationships, with only 0.3% of all sampling sites having both information about biodiversity and function, although with different taxonomic groups and functions at each site. Based on this information, we provide clear priorities to support and expand soil macroecological research.

https://www.nature.com/articles/s41467-020-17688-2

Soil is one of the most biodiverse terrestrial habitats. Yet, we lack an integrative conceptual framework for understanding the patterns and mechanisms driving soil biodiversity. One of the underlying reasons for our poor understanding of soil biodiversity patterns relates to whether key biodiversity theories (historically developed for aboveground and aquatic organisms) are applicable to patterns of soil biodiversity. Here, we present a systematic literature review to investigate whether and how key biodiversity theories (species–energy relationship, theory of island biogeography, metacommunity theory, niche theory and neutral theory) can explain observed patterns of soil biodiversity. We then discuss two spatial compartments nested within soil at which biodiversity theories can be applied to acknowledge the scale‐dependent nature of soil biodiversity.

https://onlinelibrary.wiley.com/doi/full/10.1111/brv.12567

Recent assessment of global tree restoration potential reports that under current climate conditions there would be room for additional 0.9 billion hectares of woodlands and forests Bastin (2019). This could store 205 gigatonnes of carbon making forest restoration a viable strategy for climate change mitigation. Commenting on Bastin (2019), Chazdon and Brancalion (2019) call for holistic approaches because forest restoration is a mechanism to achieve multiple goals that go beyond climate mitigation, also including biodiversity conservation, socioeconomic benefits, food security, and ecosystem services. A timely scientific debate considering the recent decision of the UN Environment Assembly in Nairobi, Kenya, to declare the coming decade 2021–2030 the UN Decade on Ecosystem Restoration.

https://www.sciencedirect.com/science/article/pii/S2095633919301996

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To reach the Paris climate targets, the mitigation capacity needs to be maximized across all components of the Earth system, especially land. Mitigation actions through land management, such as cover crops in agricultural soils, are often evaluated in terms of their carbon sequestration potential, while radiative forcing related to surface albedo changes is often ignored. The aim of this study was to assess the mitigation potential of cover crops, both as changes in biogenic greenhouse gas fluxes (CO2 and N2O) and albedo-driven radiative forcing at the top of the atmosphere (TOA). To achieve this, we have integrated a biogeochemistry model framework running on approximately 8000 locations across the European Union with detailed soil data, supplemented with time series of albedo measurements derived from satellite remote sensing. We found that carbon sequestration remained the dominant mitigation effect, with 1th and 3rd interquartile of 5.2–17.0 Mg CO2e ha−1 at 2050, and negligible changes in N2O emissions over that time-horizon. Cover crops were generally brighter than bare soils, hence, the reflected shortwave radiation at TOA ranged between 0.08–0.22 Wm−2 on average, broadly equivalent to a removal of 0.8–3.9 Mg CO2e ha−1. Through scenarios analysis, we further showed how the mitigation potential could be substantially increased by growing a high albedo chlorophyll-deficient cover crop. This radiative land management option has an additional benefit of providing its mitigation effect more rapidly than carbon sequestration, although additional studies might be warranted to evaluate local and non-local associated climatic effects, such as changes in patterns of surface temperature and precipitation.

https://iopscience.iop.org/article/10.1088/1748-9326/aba137

Soils contribute to major ecosystem services (as defined by the Millennium Ecosystem Assessment, 2005) by playing a crucial role in provisioning food and fibers, regulating water and geochemical cycles and delivering cultural services. Soils are rich in biodiversity and provide the habitat for a large number of species, many yet to be fully described. Due to this central role of soils in the delivery of ecosystem goods and services, the Soil Security concept was introduced to help Soil Science to be translated into policy guidelines for sustainable development and to be included in the Global Agenda (Koch et al., 2013; Bouma et al., 2019). Soils are indeed keys for reaching many of the Sustainable Development Goals (SDGs) by 2030. Especially SDG 2, related to fighting hunger and achieving food security, as well as SDG 15, on protecting the terrestrial environment for future generations, imply the application of sustainable soil management at the global scale. The IPCC report on Climate Change and Land names land and soil degradation through erosion, organic matter decline, contamination, soil sealing, compaction, loss of biodiversity or salinization as key challenges related to land use change (IPCC, 2019). Achieving food security and the elimination of hunger while simultaneously protecting our terrestrial environment is a great challenge that requires extensive, multidisciplinary research, including also human and social sciences: economists, geographers, sociologists, and urban planners.

https://www.frontiersin.org/articles/10.3389/fenvs.2020.00023/full

Rainfall erosivity is the driving force of soil erosion and it is characterized by a large variability in space and time. In order to obtain robust estimates of rainfall erosivity, long series of high-frequency rainfall data are needed, which are often not available for large study areas. In this study we reconstructed past rainfall erosivity in Europe for the period 1961–2018, with the aim to investigate temporal changes in rainfall erosivity. As input data, we used the Rainfall Erosivity Database at European Scale (REDES) and Uncertainties in Ensembles of Regional Reanalyses (UERRA) rainfall data. Using a set of regression models, which we derived with the application of the k-fold cross-validation approach, we computed the annual rainfall erosivity for the 1675 stations forming the REDES database. Based on the reconstructed data, we derived a rainfall erosivity trend map for Europe where the results were qualitatively validated. Among the stations showing a statistically significant trend, we observed a tendency towards more positive (15%) than negative trends (7%). In addition, we also observed an increasing tendency of the frequency of years with maximum erosivity values. Geographically, large parts of regions such as Eastern Europe, Scandinavia, Baltic countries, Great Britain and Ireland, part of the Balkan Peninsula, most of Italy, Benelux countries, northern part of Germany, part of France, among others, are characterized by a positive trend in rainfall erosivity. By contrast, negative trends in annual rainfall erosivity could be observed for most of the Iberian Peninsula, part of France, most of the Alpine area, Southern Germany, and part of the Balkan Peninsula, among others. The new dataset of rainfall erosivity trends reported in this study scientifically provides new information to better understand the impacts of the ongoing erosivity trends on soil erosion across Europe, while, from a policy perspective, the gained findings provide new knowledge to support the development of soil erosion indicators aiming at promoting mitigation measures at regional and pan-European level.

Soil is a finite resource which is vital for producing food, sequestrating carbon, regulating water and nutrients, filtering contaminants, enhancing biodiversity, storing heritage, and regulating climate (Arshad and Martin 2002). Global soils are continuously degraded because of population growth, economic development, and climate change (Montanarella et al. 2016). Soil erosion is a major form of soil degradation as more than 1 billion hectares globally are affected by some form of erosion (e.g., water, wind, and gully) (Lal 2003). Human activity and the related land use changes (deforestation and cropland increase) are the main reasons for a 2.5% increase of soil erosion by water between 2001 and 2012 (Borrelli et al. 2017).

https://link.springer.com/article/10.1007/s11027-019-09892-3

Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well‐being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas

https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.13311

Seventeen Sustainable Development Goals (SDGs) were adopted by 193 Governments at the General Assembly of the United Nations in 2015 for achievement by 2030. These SDGs present a roadmap to a sustainable future and a challenge to the science community. To guide activities and check progress, targets and indicators have been and are still being defined. The soil science community has published documents that describe the primary importance of soil for SDGs addressing hunger, water quality, climate mitigation and biodiversity preservation, and secondary relevance of soil for addressing several other SDGs. Soil scientists only marginally participated in the SDG discussions and are currently only peripherally engaged in discussions on targets or indicators. Agreement on several soil‐related indicators has still not been achieved. Involvement of soil scientists in SDG‐based studies is desirable for both developing solutions and increasing the visibility of the soil profession. Inputs into policy decisions should be improved as SDG committee members are appointed by Governments. Possible contributions of soil science in defining indicators for the SDGs are explored in this paper. We advocate the pragmatic use of soil–water–atmosphere–plant simulation models and available soil surveys and soil databases where “representative” soil profiles for mapping units (genetically defined genoforms) are functionally expressed in terms of several phenoforms reflecting effects of different types of soil use and management that strongly affect functionality.

https://onlinelibrary.wiley.com/doi/full/10.1111/sum.12518

The recurrence of storm aggressiveness and the associated erosivity density are detrimental hydrological features for soil conservation and planning. The present work illustrates for the first time downscaled spatial pattern probabilities of erosive density to identify damaging hydrological hazard-prone areas in Italy. The hydrological hazard was estimated from the erosivity density exceeded the threshold of 3 MJ ha−1 h−1 at 219 rain gauges in Italy during the three most erosive months of the year, from August to October. To this end, a lognormal kriging (LNPK) provided a soft description of the erosivity density in terms of exceedance probabilities at a spatial resolution of 10 km, which is a way to mitigate the uncertainties associated with the spatial classification of damaging hydrological hazards. Hazard-prone areas cover 65% of the Italian territory in the month of August, followed by September and October with 50 and 30% of the territory, respectively. The geospatial probability maps elaborated with this method achieved an improved spatial forecast, which may contribute to better land-use planning and civil protection both in Italy and potentially in Europe

https://www.frontiersin.org/articles/10.3389/fenvs.2019.00193/full

Soil and its ecosystem functions play a societal role in securing sustainable food production while safeguarding natural resources. A functional land management framework has been proposed to optimize the agro‐environmental outputs from the land and specifically the supply and demand of soil functions such as (a) primary productivity, (b) carbon sequestration, (c) water purification and regulation, (d) biodiversity and (e) nutrient cycling, for which soil knowledge is essential. From the outset, the LANDMARK multi‐actor research project integrates harvested knowledge from local, national and European stakeholders to develop such guidelines, creating a sense of ownership, trust and reciprocity of the outcomes. About 470 stakeholders from five European countries participated in 32 structured workshops covering multiple land uses in six climatic zones. The harmonized results include stakeholders’ priorities and concerns, perceptions on soil quality and functions, implementation of tools, management techniques, indicators and monitoring, activities and policies, knowledge gaps and ideas. Multi‐criteria decision analysis was used for data analysis. Two qualitative models were developed using Decision EXpert methodology to evaluate “knowledge” and “needs”. Soil quality perceptions differed across workshops, depending on the stakeholder level and regionally established terminologies. Stakeholders had good inherent knowledge about soil functioning, but several gaps were identified. In terms of critical requirements, stakeholders defined high technical, activity and policy needs in (a) financial incentives, (b) credible information on improving more sustainable management practices, (c) locally relevant advice, (d) farmers’ discussion groups, (e) training programmes, (f) funding for applied research and monitoring, and (g) strengthening soil science in education.

The recent efforts for obtaining vast soil spectral libraries covering a significant part of the spatial and compositional variability of soils have underscored the need for accurate and interpretable models. Herein, the application of an evolutionary Fuzzy Rule-based System (FRBS) named  (Differential Evolution based Cooperative and Competing learning of Compact Rule-based Models) for the prediction of soil properties from visible, near-infrared, and shortwave-infrared (VNIR–SWIR) laboratory spectral data obtained from the LUCAS topsoil database is investigated. FRBSs model the input–output relation with fuzzy logic statements, offering an enhanced interpretability degree for the experts over classical rule-based systems and other black box models. The proposed algorithm was statistically compared with other state of the art approaches and was found to outperform other global models, while being statistically similar with local approaches that offer lower interpretation capabilities.

https://www.sciencedirect.com/science/article/pii/S1568494619302741

https://www.sciencedirect.com/science/article/pii/S0264837718307622

The need to reduce the expected impact of climate change, finding sustainable ways to maintain or increase the carbon (C) sequestration capacity and productivity of agricultural systems, is one of the most important challenges of the twenty-first century. Olive (Olea europaea L.) groves can play a fundamental role due to their potential to sequester C in soil and woody compartments, associated with widespread cultivation in the Mediterranean basin. The implementation of field experiments to assess olive grove responses under different conditions, complemented by simulation models, can be a powerful approach to explore future land-atmosphere C feedbacks. The DayCent biogeochemical model was calibrated and validated against observed net ecosystem exchange, net primary productivity, aboveground biomass, leaf area index, and yield in two Italian olive groves. In addition, potential changes in C-sequestration capacity and productivity were assessed under two types of management (extensive and intensive), 35 climate change scenarios (ΔT-temperature from + 0 °C to + 3 °C; ΔP-precipitation from 0.0 to − 20%), and six areas across the Mediterranean basin (Brindisi, Coimbra, Crete, Cordoba, Florence, and Montpellier). The results indicated that (i) the DayCent model, properly calibrated, can be used to quantify olive grove daily net ecosystem exchange and net primary production dynamics; (ii) a decrease in net ecosystem exchange and net primary production is predicted under both types of management by approaching the most extreme climate conditions (ΔT = + 3 °C; ΔP = − 20%), especially in dry and warm areas; (iii) irrigation can compensate for net ecosystem exchange and net primary production losses in almost all areas, while ecophysiological air temperature thresholds determine the magnitude and sign of C-uptake; (iv) future warming is expected to modify the seasonal net ecosystem exchange and net primary production pattern, with higher photosynthetic activity in winter and a prolonged period of photosynthesis inhibition during summer compared to the baseline; (v) a substantial decrease in mitigation capacity and productivity of extensively managed olive groves is expected to accelerate between + 1.5 and + 2 °C warming compared to the current period, across all Mediterranean areas; (vi) adaptation measures aimed at increasing soil water content or evapotranspiration reduction should be considered the mostly suitable for limiting the decrease of both production and mitigation capacity in the next decades

Employing a linkage between a biophysical and an economic model, this study estimates the economic impact of soil erosion by water on the world economy. The global biophysical model estimates soil erosion rates, which are converted into land productivity losses and subsequently inserted into a global market simulation model. The headline result is that soil erosion by water is estimated to incur a global annual cost of eight billion US dollars to global GDP. The concomitant impact on food security is to reduce global agri-food production by 33.7 million tonnes with accompanying rises in agri-food world prices of 0.4%–3.5%, depending on the food product category. Under pressure to use more marginal land, abstracted water volumes are driven upwards by an estimated 48 billion cubic meters. Finally, there is tentative evidence that soil erosion is accelerating the competitive shifts in comparative advantage on world agri-food markets.

https://www.sciencedirect.com/science/article/pii/S0264837718319343

https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.14989

To give soils and soil degradation, which are among the most crucial threats to ecosystem stability, social and political visibility, small and large scale modelling and mapping of soil erosion is inevitable. The most widely used approaches during an 80year history of erosion modelling are Universal Soil Loss Equation (USLE)-type based algorithms which have been applied in 109 countries. Addressing soil erosion by water (excluding gully erosion and land sliding), we start this review with a statistical evaluation of nearly 2,000 publications). We discuss model developments which use USLE-type equations as basis or side modules, but we also address recent development of the single USLE parameters (R, K, LS, C, P). Importance, aim and limitations of model validation as well as a comparison of USLE-type models with other erosion assessment tools are discussed. Model comparisons demonstrate that the application of process-based physical models (e.g., WEPP or PESERA) does not necessarily result in lower uncertainties compared to more simple structured empirical models such as USLE-type algorithms. We identified four key areas for future research: (i) overcoming the principally different nature of modelled (gross) versus measured (net) erosion rates, in coupling on-site erosion risk to runoff patterns, and depositional regime, (ii) using the recent increase in spatial resolution of remote sensing data to develop process based models for large scale applications, (iii) strengthen and extend measurement and monitoring programs to build up validation data sets, and (iv) rigorous uncertainty assessment and the application of objective evaluation criteria to soil erosion modelling.

https://www.sciencedirect.com/science/article/pii/S2095633919300048

Over the last two decades or so, there has been many research carried out to understand the mechanics and spatial distribution of soil loss by water erosion and to a lesser extent of wind, piping and tillage erosion. The acquired knowledge helped the development of prediction tools useful to support decision-makers in both ex-ante and ex-post policy evaluation. In Europe, recent studies have modelled water, wind and tillage erosion at continental scale and shed new light on their geography. However, to acquire a comprehensive picture of soil erosion threats more processes need to be addressed and made visible to decision-makers. Since 1986, a small number of studies have pointed to an additional significant soil degradation process occurring when harvesting root and tuber crops. Field observations and measurements have shown that considerable amounts of soil can be removed from the field due to soil sticking to the harvested roots and the export of soil clods during the crop harvest. This study aims to scale up the findings of past studies, carried out at plot, regional, and national level, in order to obtain some preliminary insights into the magnitude of soil loss from cropland due to sugar beets and potatoes harvesting in Europe. We address this issue at European Union (EU) scale taking into account long-term (1975–2016) crop statistics of sugar beet and potato aggregated at regional and country levels.

During the period 2000–2016, sugar beets and potatoes covered in average ca. 4.2 million ha (3.81%) of the EU-28 arable land estimated at 110 million ha. The total Soil Loss by Crop Harvesting (SLCH) is estimated at ca. 14.7 million tons yr⁻¹ in the EU-28. We estimate that ca. 65% of the total SLCH is due to harvesting of sugar beets and the rest as a result of potatoes harvesting.

https://www.sciencedirect.com/science/article/pii/S0048969719304887

The sampling method is a key aspect when designing a soil monitoring network. The determination of any physical and chemical property can be subject to uncertainties because of the sampling method. In this study, we compared the efficiency of sampling with a spade and a gouge auger for the physicochemical characterization of topsoil samples from 150 mineral soils under various land cover (LC) classes in Switzerland taken within the LUCAS 2015 Survey. The sampling methods differed in their scheme, accuracy of litter removal and control of sampling depth, which were more rigorous with the gouge auger than the spade method. Values of root mean square error of properties ranged between 1/2 and 1/30 of their mean values. Lin's concordance correlation coefficient showed that the spade and gouge auger methods produced similar results for all properties (LCCC ≥0.73), with a better relation for arable land than other LC classes. A poor relation was observed for potassium (LCCC = 0.35) in coniferous forest because of its shallow distribution in depth. We concluded that the simpler and cheaper spade method is an accurate method for topsoil sampling at the continental scale. From this study, it is clear that some improvements in the control of sampling depth and the accuracy of litter removal are needed, especially when monitoring forest soils and properties that change rapidly with depth. Spade sampling can help to expand the implementation of soil monitoring surveys at the continental scale at relatively low sampling cost.

https://onlinelibrary.wiley.com/doi/full/10.1111/ejss.12862

New challenges and policy developments after 2015 (among others, the Common Agricultural Policy (CAP), Sustainable Development Goals (SDGs)) are opportunities for soil scientists and soil erosion modellers to respond with more accurate assessments and solutions as to how to reduce soil erosion and furthermore, how to reach Zero Net Land Degradation targets by 2030. This special issue includes papers concerning the use of fallout for estimating soil erosion, new wind erosion modelling techniques, the importance of extreme events (forest fires, intense rainfall) in accelerating soil erosion, management practices to reduce soil erosion in vineyards, the impact of wildfires in erosion, updated methods for estimating soil erodibility, comparisons between sediment distribution models, the application of the WaTEM/SEDEM model in Europe, a review of the G2 model and a proposal for a land degradation modelling approach. New data produced from field surveys such as LUCAS topsoil and the increasing availability of remote sensing data may facilitate the work of erosion modellers. Finally, better integration with other soil related disciplines (soil carbon, biodiversity, compaction and contamination) and Earth Systems modelling is the way forward for a new generation of erosion process models.

https://www.sciencedirect.com/science/article/pii/S0013935119301264

The Common Agricultural Policy (CAP) of the European Union (EU) has been highly successful in securing the supply of food from Europe’s agricultural land. However, new expectations have emerged from society on the functions that agricultural land should deliver, including the expectations that land should regulate and purify water, should sequester carbon to contribute to the mitigation of climate change, should provide a home for biodiversity and allow for the sustainable cycling of nutrients in animal and human waste streams. Through a series of reforms of the CAP, these expectations, or ‘societal demands’ have translated into a myriad of EU and national level policies aimed at safeguarding the sustainability and multifunctionality of European agriculture, resulting in a highly complex regulatory environment for land managers. The current reform of the CAP aims to simultaneously simplify and strengthen policy making on environmental protection and climate action, through the development of Strategic Plans at national level, which allow for more targeted and context-specific policy formation. In this paper, we contribute to the knowledge base underpinning the development of these Strategic Plans by mapping the variation in the societal demands for soil functions across EU Member States, based on an extensive review of the existing policy environment relating to sustainable and multifunctional land management. We show that the societal demands for primary production, water regulation and purification, carbon sequestration, biodiversity and nutrient cycling vary greatly between Member States, as determined by population, farming systems and livestock densities, geo-environmental conditions and landscape configuration. Moreover, the total societal demands for multifunctionality differs between Member States, with the lowest demands found in Member States that have designated the higher shares of EU CAP funding towards ‘Pillar 2′ expenditure, aimed at environmental protection and regional development. We review which lessons can be learnt from these observations, in the context of the proposals for the new CAP for the period 2021–2027, which include enhanced conditionality of direct income support for farmers and the instigation of eco-schemes in Pillar 1, in addition to Agri-Environmental and Climate Measures in Pillar 2. We conclude that the devolution of planning to Strategic Plans at national level provides an opportunity for more effective and targeted incentivisation of sustainable land management, provided that these plans take account for variations in the societal demand for soil functions, as well as the capacity of contrasting soils to deliver on this multifunctionality.

Soil mapping is an essential method for obtaining a spatial overview of soil resources that are increasingly threatened by environmental change and population pressure. Despite recent advances in digital soil-mapping techniques based on inference, such methods are still immature for large-scale soil mapping. During the 1970s, 1980s and 1990s, soil scientists constructed a harmonised soil map of Europe (1:1 000 000) based on national soil maps. Despite this extraordinary regional overview of the spatial distribution of European soil types, crude assumptions about soil properties were necessary for translating the maps into thematic information relevant to management. To support modellers with analytical data connected to the soil map, the European Soil Bureau Network (ESBW) commissioned the development of the soil profile analytical database for Europe (SPADE) in the late 1980s. This database contains soil analytical data based on a standardised set of soil analytical methods across the European countries. Here, we review the principles adopted for developing the SPADE database during the past five decades, the work towards fulfilling the milestones of full geographic coverage for dominant soils in all the European countries (SPADE level 1) and the addition of secondary soil types (SPADE level 2). We illustrate the application of the database by showing the distribution of the root zone capacity and by estimating the soil organic carbon (SOC) stocks at a depth of 1 m for Europe to be 60×1015 g. The increased accuracy, potentially obtained by including secondary soil types (level 2), is shown in a case study to estimate SOC stocks in Denmark. Until data from systematic cross-European soil-sampling programmes have sufficient spatial coverage for reliable data interpolation, integrating national soil maps and locally assessed analytical data into a harmonised database remains a powerful resource to support soil resources management at regional and continental scales by providing a platform to guide sustainable soil management and food production.

https://soil.copernicus.org/articles/5/289/2019/

Over the last 2 decades, geospatial technologies such as Geographic Information System and spatial interpolation methods have facilitated the development of increasingly accurate spatially explicit assessments of soil erosion. Despite these advances, current modelling approaches rest on (a) an insufficient definition of the proportion of arable land that is exploited for crop production and (b) a neglect of the intra‐annual variability of soil cover conditions in arable land. To overcome these inaccuracies, this study introduces a novel spatio‐temporal approach to compute an enhanced cover‐management factor (C) for revised universal soil loss equation‐based models. It combines highly accurate agricultural parcel information contained in the Land Parcel Identification System with an object‐oriented Landsat imagery classification technique to assess spatial conditions and interannual variability of soil cover conditions at field scale. With its strong link to Land Parcel Identification System and Earth observation satellite data, the approach documents an unprecedented representation of farming operations. This opens the door for the transition from the currently used potential soil erosion risk assessments towards the assessment of the actual soil erosion risk. Testing this method in a medium‐size catchment located in the Swiss Plateau (Upper Enziwigger River Catchment), this study lays an important foundation for the application of the very same methods for large‐scale or even pan‐European applications. Soil loss rates modelled in this study were compared with the insights gained from emerging techniques to differentiate sediment source contribution through compound‐specific isotope analysis on river sediments. The presented technique is adaptable beyond revised universal soil loss equation‐type soil erosion models.

https://onlinelibrary.wiley.com/doi/abs/10.1002/ldr.2898

The soils of the Mediterranean Basin are the products of soil processes that have been governed by a unique convergence of highly differentiated natural and anthropogenic drivers. These soils are expected to be dramatically affected by future climate and societal changes. These changes imply that suitable adaptive management strategies for these resources cannot simply be transposed from experiments that are performed in other regions of the world. Following a framework that considers the chain of “drivers-soil process-soil capital-ecosystem services/disservices,” the paper review the research undertaken in the Mediterranean area on three types of Mediterranean soil degradation than can be expected under global change: (i) soil losses due to the increase of drought and torrential rainfall; (ii) soil salinization due the increase of droughts, irrigation, and sea level; and (iii) soil carbon stock depletion with the increase of temperature and droughts. The possible strategies for mitigating each of these degradations have been largely addressed and are still studied in current research projects. They should include changes in agricultural practices, soil water management, and vegetal material. As a pre-requisite for the site-specific adaptations of such mitigation strategies within viable Mediterranean agrosystems, it is highlighted that methodological advances are necessary in integrated assessment of agricultural systems and in finer resolution soil mapping.

https://www.nature.com/articles/s41559-018-0573-8

We present an updated version of the European landslide susceptibility map ELSUS 1000 released through the European Soil Data Centre in 2013. The ELSUS V2 map shows the landslide susceptibility zonation for individual climate-physiographic zones across Europe. ELSUS V2 covers a larger area of Europe than ELSUS 1000 at a higher spatial resolution (200 × 200 m). The updated map was prepared using the same semi-quantitative method as for ELSUS 1000, combining landslide frequency ratios information with a spatial multi-criteria evaluation model of three thematic predictors: slope angle, shallow subsurface lithology and land cover. However, the new map was prepared using also: (i) an extended landslide inventory, containing 30% of additional locations for model calibration, map validation and classification and (ii) a new lithological data set derived from the International Hydrogeological Map of Europe (IHME). The new version of the map increases the overall predictive performance of ELSUS by 8%.

https://www.tandfonline.com/doi/full/10.1080/17445647.2018.1432511

https://link.springer.com/article/10.1007/s10661-017-6415-3

Land desertification is recognized as a major threat to soil resources in arid, semi-arid Mediterranean areas. The use of widely applicable methodologies can facilitate the identification of land desertification risk spatio-temporal trends, which allows transnational comparison and support the development of soil management practices and policies, protecting the valuable soil resources. The aim of this study is to improve and use the Environmentally Sensitive Areas (ESAs) MEDALUS methodology, in order to provide a qualitative assessment for desertification risk trends in Greece, within the last 45 years. The Management, Vegetation, Soil and Climate quality indices (MQI, VQI, SQI, CQI) and the sub-sequent Environmental Sensitive Areas Index (ESAI) have been modeled for three periods in the entire Greek territory. The four quality indices are divided in two main categories, based on data availability and inherent characteristics, such as the pace of change during the studied period. Particular emphasis is given to the assessment of MQI, by integrating criteria which derived from national policies and the elaboration of national statistical data. The results show about 9% increase of the areas characterized as Critical to land desertification risk, while Fragile, Potentially affected and Non-affected areas decrease by 3.7%, 3.6%, 2.5% respectively. The applied approach for MQI can reveal areas where particular attention to management practices is required and improves the performance of the overall desertification risk index.

https://www.sciencedirect.com/science/article/pii/S0341816218301577

Much research has been carried out on modelling soil erosion rates under different climatic and land use conditions. Although some studies have addressed the issue of reduced crop productivity due to soil erosion, few have focused on the economic loss in terms of agricultural production and gross domestic product (GDP). In this study, soil erosion modellers and economists come together to carry out an economic evaluation of soil erosion in the European Union (EU). The study combines biophysical and macroeconomic models to estimate the cost of agricultural productivity loss due to soil erosion by water in the EU. The soil erosion rates, derived from the RUSLE2015 model, are used to estimate the loss in crop productivity (physical change in the production of plants) and to model their impact on the agricultural sector per country. A computable general equilibrium model is then used to estimate the impact of crop productivity change on agricultural production and GDP. The 12 million hectares of agricultural areas in the EU that suffer from severe erosion are estimated to lose around 0.43% of their crop productivity annually. The annual cost of this loss in agricultural productivity is estimated at around €1.25 billion. The computable general equilibrium model estimates the cost in the agricultural sector to be close to €300 million and the loss in GDP to be about €155 million. Italy emerges as the country that suffers the highest economic impact, whereas the agricultural sector in most Northern and Central European countries is only marginally affected by soil erosion losses.

https://onlinelibrary.wiley.com/doi/full/10.1002/ldr.2879