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Once one of the most severe soil loss regions worldwide, the Chinese Loess Plateau has experienced large-scale land use changes and vegetation restoration in the past few decades. Understanding how land use change affects soil erosion is critical in the region's ecological construction and land management. In this study, the Beiluo River Basin covering 26,905 km2 in the hinterland of the Loess Plateau was selected to investigate vegetation restoration and its impacts on soil loss rates over the last 50 years. Results show that land use in the basin has changed considerably, mainly reflected in the upper reaches. From 1970–2020, cropland in the upper reaches decreased by 54%, directly leading to a 9.1-fold increase in forested land. Landsat-NDVI shows vegetation coverage increased from 21.1% to 69.9% over time. Vegetation coverage changed from 48.1% to 78.7% for the entire basin. The Chinese Soil Loss Equation (CSLE) was used and confirmed to be satisfactory with a high coefficient of determination (R2, 0.89) and a strong Nash–Sutcliffe efficiency coefficient (0.72), although an underestimation exists. With the change in land use, the specific soil loss simulated in the upper reaches maintained a high rate of around 8,000 t·km−2·yr−1 from the 1970s to the 1990s, dramatically dropping to 3,058 t·km−2·yr−1 in the 2000s, then attenuated to 1,321 t·km−2·yr−1 in the 2020s. For the entire basin, soil loss rates dropped from 4,090 to 1,848 and 890 t·km−2·yr−1 from the 1970s to the 2000s and 2020s, respectively. Attribution analysis showed that the dominant factor in the change in soil loss rates in the 1980s and 1990s relative to the 1970s was the change in rainfall erosivity for the entire watershed. However, with vegetation coverage increasing to 59.0% in the 2000s, vegetation restoration rapidly converted to the dominant factor contributing 78.3% to soil loss decrease in that period. With expanding vegetation cover, its contribution grew to 84.9% in the 2020s. The shift is evident in each reach of the basin except the terrain-plain area with the majority of farmland. The findings are helpful for sustainable land use planning and socio-economic development on the Loess Plateau and in similar areas.

Vegetative barriers have proven their effectiveness in controlling erosion and promoting other ecosystem services in agricultural areas. This has led to their conservation and promotion as landscape elements by the Common Agricultural Policy and other policy initiatives. However, predicting their efficiency in reducing hydrologic connectivity presents a large uncertainty (Gumiere et al., 2011).This communication presents an analysis of trapping efficiency of sediment, runoff, and nutrients (P and N) by vegetative barriers aimed to provide a statistical approach to efficiency, based on a review of available studies, considering two climates: humid and arid/semi-arid (Muñoz et al, 2022). For this, different independent variables were grouped and identified to explore its influence: i) those defining the vegetative barrier dimension (width, slope of the plot, and area ratio buffer/plot) and ii) those related to experimental conditions (type of vegetation, soil protection of the non-buffered area, type of climate, type of experimental measurement and origin of the rainfall). A more detailed analysis was performed with the studies which reproduce similar situations to the ones occurring naturally (natural rainfall and paired plots).In general, average trapping efficiencies for runoff and sediment are 40.1 and 62.6% and ranging between -81.0 to 99.9% and -109 to 100%, respectively. For nutrients, values of trapping efficiencies had an average of 44.9 and 38.4% for phosphorus and nitrogen, respectively. The lack of data and the large variability among and within the measurements from the studies considered in our review only allowed to detect slight trends and statistically significant differences in some cases for the different variables analysed.In order to provide guidelines to farmers and technicians, a probabilistic model was developed for sediment trapping efficiency regarding the width of the vegetative barrier and the climatic region. The model showed that in 92% of the cases, a vegetative barrier will reduce erosion in humid climates while this trapping efficiency will be 100% in semi-arid/arid conditions. Grouping the vegetative barriers’ width in different intervals, it was observed that the maximum trapping efficiency is ~80 % for a width of 2.75 to 3-m in arid/semi-arid climate and 5 to 6-m in humid regions. Acknowledgement: This work supported by the project PID2019-105793RB-I00 financed by the Spanish Ministry of Science and Innovation, and project TUdi, GA 101000224, of the European Union’s Horizon 2020 research and innovation programmeReferencesGumiere, S. J., Le Bissonnais, Y., Raclot, D., & Cheviron, B. (2011). Vegetated filter effects on sedimentological connectivity of agricultural catchments in erosion modelling: A review. Earth Surface Processes and Landforms, 36(1), 3–19. https://doi.org/10.1002/esp.2042.Muñoz, J. A., Guzmán G., Soriano M.A., & Gómez J. A. (2022). Trapping efficiency of vegetative barriers in agricultural landscapes. An operational model from a review of available information. Manuscript submitted for publication.

Within the scope of the TUdi project, EU Horizon 2020 Grant Agreement No 101000224, a questionnaire was responded to by more than 400 farmers from seven countries in Europe and China, aiming to assess farmers' major concerns and develop Decision Support Tools targeted at these issues. One tool currently being developed targets soil erosion and seeks to provide farmers with publicly available historical satellite imagery in a user-friendly platform, as well as guidelines on easy-to-use methodology to assess the degree of soil erosion on the field. The questionnaires also revealed that many farmers do not use official data or digital maps to help make management decisions but are willing to apply simple tools for assessing soil degradation processes. With this, the project hopes to contribute to democratizing access to science, helping farmers – ultimately, the ones who implement soil conservation practices – to make data-driven decisions on soil management and exploring alternatives. The preliminary version of this tool will be presented at the workshop.Research has been supported by project TUDI (European Union's Horizon 2020 research and innovation program under grant agreement No 101000224)

In many agricultural regions, the maintenance of profitability and other ecosystem services without intensifying soil loss due to erosion is still a challenge on a global scale. However, the first steps to address this challenge should be done at farm scale where technicians and farmers have the possibility to make decisions and modify agricultural practices considering local conditions of each farm.The Protected Appellation of Origin Estepa (DOP Estepa) in Southern Spain, encompass approximately 40,000 ha of olives trees under different soil management systems. In this region, the awareness of balancing economical and environmental sustainability is a fact and there has been a strong collaboration among stakeholders since 2019, reinforced within two large cooperative actions, the EIP-Agri Operational Group BIOLIVAR and the H2020 TUdi project.One of the activities developed in the DOP Estepa was to evaluate the hillslope water erosion risk at farm plot. For this, a GIS project was created (QGIS v.3.4.11) to aggregate spatial information to apply RUSLE (Dabney et al., 2012). All the key layers freely provided by different regional and national institutions (e.g. CNIG, REDIAM, CAPADR-JA) and Sentinel-2-L-2A images (EOS, 2020). The LS factor was obtained using the algorithms accessible from QGIS based on Desmet and Govers (1996), the K factor was determined based on the soil classification and calibration for different soil types made by Gómez et al. (2014) and R was directly taken from the map provided by REDIAM. The C factor was calculated for the most common soil managements implemented in the area (previously identified through farmers’ questionnaires by Gómez et al., 2021) using the ORUSCAL tool (Biddoccu et al., 2020, Gómez et al., 2021). The use of bare soil or temporary cover crop at plot level was identified comparing differences in the enhanced vegetation index EVI between winter 2019 and summer 2020 Sentinel images (Guzmán et al. (2022)).This communication presents a prototype of a geospatial database, and future steps to improve it, on which its expansion for other purposes can be easily evaluated by technicians, such as the effect of alternative management scenarios on soil erosion or adding other variables of interest such as, farm yield or pests’ incidence. Its final goals are to establish a monitoring system to detect areas with higher risk of soil erosion, raise farmers’ awareness on the need to improve soil conservation and, in general terms, to contribute to the improvement of olive orchards’ sustainability in the region.Acknowledgements: PID2019-105793RB-I00 financed by the Spanish Ministry of Science and Innovation, GOPO-SE-20-0002 of the EIP-Agri, and TUdi, GA 101000224, of the European Union’s H2020 research and innovation programme.References:Biddoccu et al. 2020. International Soil and Water Conservation Research 8.Dabney et al. 2012. Journal of Soil and Water Conservation 67.Desmet and Govers. 1996. Journal of Soil and Water Conservation 51(5).EOS. Land viewer. 2020. https://eos.com/landviewer/.Gómez et al. 2014. Agriculture 4.Gómez et al. 2020. https://digital.csic.es/handle/10261/216656.Gómez et al. 2021. International Soil and Water Conservation Research 9(3).Guzmán et al. 2022. Land Use Policy 116.

This study compares the distribution of bulk soil organic carbon (SOC), its fractions (unprotected and physically, chemically, and biochemically protected), available phosphorus (Pavail), organic nitrogen (Norg), and stable isotope (δ15N and δ13C) signatures at four soil depths (0–10, 10–20, 20–30, and 30–40 cm) between a nearby open forest reference area and a historical olive orchard (established in 1856) located in southern Spain. In addition, these soil properties, as well as water stable aggregates (Wsagg), were contrasted at eroding and deposition areas within the olive orchard, previously determined using 137Cs. SOC stock in the olive orchard (about 40 t C ha−1) was only 25 % of that in the forested area (about 160 t C ha−1) in the upper 40 cm of soil, and the reduction was especially severe in the unprotected organic carbon. The reference and the orchard soils also showed significant differences in the δ13C and δ15N signals, likely due to the different vegetation composition and N dynamics in both areas. Soil properties along a catena, from erosion to deposition areas within the old olive orchard, showed large differences. Soil Corg, Pavail and Norg content, and δ15N at the deposition were significantly higher than those of the erosion area, defining two distinct areas with a different soil quality status. These overall results indicate that the proper understanding of Corg content and soil quality in olive orchards requires the consideration of the spatial variability induced by erosion–deposition processes for a convenient appraisal at the farm scale., This research has been supported by the Spanish Ministry of Economy and Competitiveness (grant no. AGL2015-40128-C03-01) and the European Commission (SHui, grant no. 773903).

EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022., Water erosion measurement has been widely studied under different conditions using traditional approaches such as erosion collectors and more innovative ones such as sediment tracers. La Conchuela is a commercial olive orchard located in Southern Spain. In 2008, six closed runoff plots, where regular machine traffic during farm operations was allowed, were established. Runoff water was channeled from the plots and collected by tipping-bucket gauges with 5-min resolution. This was completed with a sediment trap located upstream of the tipping buckets and a device to collect an integrated sample of the runoff downstream of the tipping buckets (Gómez & Guzmán, 2021). In two of these plots ground cover was controlled with tillage during the whole year while the rest keep a temporary cover crop during fall and winter. In two of the plots (one with bare soil and other with temporary cover crop), the top 5 cm of the inter tree rows soil were tagged with magnetite. During the following years, three soil sampling campaigns (2008, 2010, 2016) were performed to measure variations of magnetic susceptibility within the soil surface and profile. Seventy locations at both plots were sampled at three depth intervals (0-1, 1-8, 8-12 cm in 2008 and 2010). A third sampling was carried out at 0-2, 2-10, 10-20 cm in 2016 at the same locations. Furthermore, twenty additional samples from 20-30, 30-40, 40-50, 50-60 cm were taken to check if tagged soil went deeper into the soil profile. In all these samplings, tree and inter tree rows were distinguished. Background susceptibility and bulk density at each depth, were characterised at the three sampling campaigns (Guzmán & Gómez, 2017). During the period 2008-2019 there were not statistically significant differences between managements, bare soil vs temporary cover crops, in runoff or soil losses. Nevertheless, average runoff and soil losses had a trend to lower values for the cover crop treatment (142.9 mm and 16.5 t ha-1) as compared to bare soil (155.8 mm and 23.8 t ha-1). With the help of the magnetic tracer, the estimated erosion rates within the plots during 2009-2010 (the rainiest hydrological year within the study period with a precipitation of 1048.5 mm) were 115 t ha-1 and 58 t ha-1 in the bare soil plot and 62 t ha-1 and 44 t·ha-1 in the cover crop plot, from inter-tree rows and tree rows, respectively. The evolution of susceptibility suggests the potential of magnetite monitoring vertical fluxes at the mid-term also, due to wetting-drying cycles of vertic soils and soil disturbance agricultural practices. In fact, magnetic iron oxide was detected at initially untagged deeper soil layers (20-60 cm) in both inter-tree and tree rows. This highlights the relevance of accounting vertical displacement in any kind of tracer study in vertic soils and its implications at the medium-term (2008-2016) for the determination of erosion rates which will be presented in this communication.

Trabajo desarrollado bajo la financiación del proyecto “Soil Hydrology research platform underpinning innovation to manage water scarcity in European and Chinese cropping Systems” (773903), coordinado por José Alfonso Gómez Calero, investigador del Instituto de Agricultura Sostenible (IAS)., This manuscript presents a questionnaire-based study aimed to provide a detailed analysis on the different soil management carried out by olive farmers in two representative olive-growing areas in southern Spain (Cordoba and Estepa), their perceptions on cover crop use and the possible influence of the different types of farms and farmers’ typologies on these perceptions. Our results show a relatively large variability of soil management, with fourteen options, as a result of a combination of different alternatives for bare soil and cover crops with the use or not of pruning residues, but with a great similarity between both areas. The results indicate a high adoption of soil conservation measures in the two study areas, with 63% of farmers using cover crops and 80% a mulch of pruning residues, higher than that reported in previous studies in Southern Spain, and a trend of lower use of these techniques by less experienced and younger farmers. This high penetration of soil conservation measures resulted in a significant reduction of soil erosion risk, as indicated by the relatively low values for the cover and management factor (C) of RUSLE, also calculated and presented in this study, but also the possibility of focusing further efforts on farmers with less experience. Our results indicate the persistence of a minor, but relevant, percentage of farmers using bare soil management (37%) and no mulching (20%), with a moderate concern on the impact of soil erosion on soil degradation and provision of ecosystem services. This suggests the need to concentrate efforts also on this cluster of farmers to enhance the success of what seems to be a remarkable expansion of the use of soil conservation measures in recent decades in Southern Spain, but also in similar areas in the Mediterranean basin., This work was supported by P12-AGR-0931 (Andalusian Government), AGL2015-65036-C3-1-R and PID2019-105793RB-I00 (Spanish Government), SHui (European Commission Grant Agreement number: 773903) and EU-FEDER funds, as well as by the cooperative agreement between the DOP Estepa and the University of Cordoba. All this support is gratefully acknowledged.

Trabajo desarrollado bajo la financiación del proyecto “Soil Hydrology research platform underpinning innovation to manage water scarcity in European and Chinese cropping Systems” (773903), coordinado por José Alfonso Gómez Calero, investigador del Instituto de Agricultura Sostenible (IAS)., Among the agricultural practices promoted by the Common Agricultural Policy to increase soil functions, the use of cover crops is a recommended tool to improve the sustainability of Mediterranean woody crops such as olive orchards. However, there is a broad range of cover crop typologies in relation to its implementation, control and species composition. In that sense, the influence of different plant species on soil quality indicators in olive orchards remains unknown yet. This study describes the effects of four treatments based on the implementation of different ground covers (CC-GRA: sown cover crop with gramineous, CC-MIX: sown cover crop with a mixture of species and CC-NAT: cover crop with spontaneous vegetation) and conventional tillage (TILL) on soil erosion, soil physicochemical and biological properties after 8 years of cover crop establishment. Our results demonstrated that the presence of a temporary cover crop (CC), compared to a soil under tillage (TILL), can reduce soil losses and maintain good soil physicochemical properties and modify greatly the structure and diversity of soil bacterial communities and its functioning. The presence of a homogeneous CC of gramineous (Lolium rigidum or Lolilum multiflorum) (CC-GR) for 8 years increased the functional properties of the soil as compared to TILL; although the most relevant change was a modification on the bacterial community composition that was clearly different from the rest of treatments. On the other hand, the use of a mixture of plant species (CC-MIX) as a CC for only two years although did not modify greatly the structure and diversity of soil bacterial communities compared to the TILL soil, induced significant changes on the functional properties of the soil and reverted those properties to a level similar to that of an undisturbed soil that had maintained a natural cover of spontaneous vegetation for decades (CC-NAT)., This work was supported by the EU SoilMan project (grant number 01LC1620) funded through the 2015–2016 BiodivERsA COFUND call for research proposals, with national funds through PCIN-2016-048 project by the Spanish Ministry of Economy and Competitiveness (MINECO), SHui project (GA 773903), and by projects PID2019-105793RB-I00, AGL2008-00344 from ‘Ministerio de Ciencia e Innovación’, AGL-2012–37521 from ‘Ministerio de Economia y Competitividad’ of Spain, Project P10-AGR-5908 from ‘Consejería de Economía, Innovación y Ciencia’ Junta de Andalucía, and FEDER financial support from the European Union.

Maintenance of ground cover vegetation in olive orchards has been shown to reduce soil and runoff losses as compared to bare soil. However, extrapolation of its impact at hillslope scale under different conditions still challenging for several reasons. One is the limited duration of available experiments, usually shorter than 3 years, which can´t capture the annual variability in precipitation typical of Mediterranean type of climate. A second reason is the small scale in which many experiments are carried out, which do not capture all the relevant erosion processes at hillslope scale. A third reason, hardly discussed, is the use of the runoff plots that limits traffic resulting in conditions that might not be fully representative of actual orchards. For evaluating the effect of temporary cover crops on water erosion processes in olives at hillslope scale, runoff and soil losses have been monitored from 2008 to 2019 in La Conchuela. This is an olive farm located in Southern Spain, where average annual precipitation is 655 mm, on Typic Haploxerert (clay content > 50%). Six runoff plots (14x24 m) delimited by steel beams on concrete foundation were established in a 13.4 % slope, containing 3 rows of 4 trees. This allows normal farm operations. Since 2008-2009, two soil management systems, conventional tillage (CT) and temporary cover crops (CC), were tested. In the two CT plots ground vegetation was controlled by 2-3chisel ploughing passes during the year. CC in the other four plots consisted of sowing manually in mid Fall a grass or a mix with grasses every 1 to 3 years without disturbing the soil surface, been mowed in early Spring. The aim of this cover crop was to be grown up spontaneously from seed produced the previous year. Weeds along the tree rows are controlled by herbicides in both cases.No significant differences were detected (p < 0.05) for the whole period, although CC showed lower runoff and soil losses values. Runoff data ranged from 157.7 ± 61.2 to 144.5 ± 46.4 mm, and soil losses varied from 24.3 ± 9.1 to 16.4 ± 7.0 t·ha-1 at the CT and CC treatments respectively. The lack of statistical differences can be explained by the large variability recorded in the measurements at the six plots, especially at the CC due to the specific weather and traffic conditions. Our experiment shows how in a crop, olives, subject to intense traffic during the harvesting season (happening in late fall or early winter, rainy season) and in an orchard on heavy soils, maintenance of a good cover crop is challenging in many years. Our results call for caution when extrapolating the benefits of cover crops in olives from the experimental plots to real world conditions. It also highlights the need for improved soil management under these conditions (e.g. controlled traffic, combination with inert mulch, …) to improve soil and water conservation in intensively cultivated olive orchards in heavy soils.

Project Co-ordinators: Dr. Jose Alfonso Gómez Calero (Instituto de Agricultura Sostenible (IAS-CISC), Dr. Weifeng Xu (Fujian Agriculture and Forest University, FAFU)., Soil erosion plays an important role in C cycling at farm scale, especially in bare soil areas. In Mediterranean woody crops, temporary cover crops (CC) effectively reduce soil erosion and increase total and protected soil organic carbon (SOC) fractions. However, the effects of CC in olive groves on the preferential loss of organic carbon (Corg) fractions remains poorly understood. To address this issue, in four plots with seeded CC and two tilled plots (CT) in a Spanish olive grove, the unprotected and protected Corg fractions were measured in soil and sediments over the course of a hydrological year. The sediment/soil C enrichment ratios (ERSOC) were calculated, and results analysed considering the rainfall regimes of the site: dry (DS), heavy-rainy (HRS) and rainy (RS). Total, unprotected and protected Corg contents in the top 5 cm soil of CC plots were 46 %, 88.4 % and 28.5 %, respectively, higher than those of CT. 79.7 % and 70.3 % of the annual sediment yield (SY) was collected during December in CC and CT plots, respectively. Soil loss in CC plots ( = 9.2 Mg ha–1 yr–1) was significantly lower (−55.6 %) than that in CT plots. Despite that the average eroded Corg was higher in the CT ( = 222 kg C ha–1 yr–1) compared to CC ( = 148 kg C ha–1 yr–1) plots differences were not significant due to the higher Corg concentration in the sediment from CC plots. The highest proportion of eroded Corg (44%–45%) corresponded to the physically protected fraction. The highest ERSOC (1.99 and 2.04 for CC and CT, respectively) was recorded in DS whereas the lowest was in the RS (0.90) and HRS (0.96) seasons. The mean ERSOC were of 1.00 and 0.92 in the CC and CT plots, with no significant difference. The fact that most of the SY was recorded in one month, when CC plants were not fully developed, might explain the ERSOC at 1, and why their presence did not modify it. This study demonstrates that CC favours greater total, unprotected and protected Corg fractions in the topsoil, promoting soil C sequestration. The asynchrony between the periods of full development of the CC plants and those with the highest rainfall erosivity prevented any selectiveness of the eroded Corg. Thus, fast-growing CC plant species with short life-cycles are recommended, as well as adequate management to promote self-seeding avoiding soil disturbance for seeding in erosion prone seasons., This research has been supported by the Spanish Government (grants no. AGL2015-40128-C03-01 and PID2019-105793RB-I00), FEDER funds and the European Commission (SHui, grant no. 773903) and the H2020 PRIMA project SUSTAINOLIVE (grant no. 1811).

The introduction of temporary grassland into an annual crop rotation is recognized to improve soil ecosystem services, and resulting legacies can be beneficial for the following crops. In this context, the aim of the present study was to evaluate legacy effects of introducing temporary grassland into an annual crop rotation on five ecosystem services (i) soil structure maintenance (aggregate stability), (ii) water regulation (saturated hydraulic conductivity), (iii) biodiversity conservation (microbial biomass and microbial metabolic activity, as well as microorganism, enchytraeid, springtail and earthworm communities), (iv) pathogen regulation (soil suppressiveness to Verticillium dahliae), and (v) forage production and quality. Three crop rotation schemes, maintained for twelve years, were compared in four random blocks, one being an annual crop rotation without grassland (0%), another with a medium percentage of grassland (50%, corresponding to 3 years of continuous grassland in the crop rotation), and a third one with a high percentage of grassland in the crop rotation (75%, corresponding to 6 years of continuous grassland in the crop rotation). The results showed that the grassland introduction into an annual crop rotation improved, whatever the duration of the grassland, soil structure maintenance and biodiversity conservation, while it decreased pathogen regulation and did not modify water regulation. Comparing the two crop rotations that included grassland, indicated a stronger beneficial grassland legacy effect for the higher proportion of grassland concerning soil structure maintenance and biodiversity conservation. By contrast, water regulation, pathogen regulation and forage production were not affected by the legacy of the 75% grassland during the rotation. Overall, our findings demonstrated the extent to which grassland legacies are affecting the current state of soil properties and possible ecosystem services provided. To improve ecosystem services, soil management should take legacy effects into account and consider longer timeframes to apply beneficial practices., This work was supported by the EU SoilMan project (grant number 01LC1620) funded through the 2015–2016 BiodivERsA COFUND call for research proposals, with national funders the Federal Ministry of Education and Research (BMBF), the French National Research Agency (ANR), the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS), the Spanish Ministry of Economy and Competitiveness (MINECO), the Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCDI), the European Regional Development Fund (Centre of Excellence EcolChange). We would like to thank the National Research Infrastructure “Agro-écosystèmes, Cycles Biogéochimique et Biodiversité” (ACBB) http://www.soere-acbb for providing access to an excellent field experiment and the “the AnaEE France (ANR-11-INBS-0001)”, “AllEnvi” and “CNRS-INSU” which support it. We thank Météo France for meteorological data.

This chapter addresses the complex issue of assessing soil erosion and sediment transport rates. First, the basic concepts and involved processes are presented and defined. Second, a brief explanation of the role played by the spatial and temporal scales introduces the list of direct (e.g., measurement of changes in soil level, splash devices, runoff collectors, gauging stations, sediment traps in streams) and indirect (e.g., sediment tracers, sediment cores and bathymetry) methods used to obtain onsite measurements and the usefulness of numerical approaches (e.g., empirical and process-based models, indices, machine learning techniques) to calculate and map the spatially distributed hydrological response of the soil. Third, two case studies in agricultural areas with permanent crops (olive groves) in southern Spain and three hydrological basins of different sizes (small, medium, and large ones) in north-eastern Spain are presented as case studies. Final remarks and current challenges close the text.

Trabajo presentado en la EGU General Assembly (Annual Meeting of the European Geosciences Union), celebrada online deñ 4 al 8 de mayo de 2020., So far, it does not exist a set of tracers which fulfill all the characteristics for being an idealsediment tracer such as, environmentally friendly, inexpensive or easily analysed (Zhang et al.,2001). For this reason, and in order to address some of the unsolved issues of water erosionprocesses, more research enquiring into the development of these soil and sediment tracers isneeded.Iron oxide-based tracers has been already tested in several water erosion trials with satisfactoryresults (e.g. Guzmán et al., 2010, 2013, 2015). In 2015, three cascade plots with a different ironoxide (magnetite, hematite and goethite) each were set up in order to evaluate soil redistributionafter the rainy season (Obereder et al., 2016). While these authors presented the total iron contentof sediments after clorhydric acid extraction, the present study will show only the free iron contentof soil and sediments using a different extraction method (CBC, citrate-bicarbonate-ditionite), asthis method is more adequate in high iron content soils, as is our case.The results depict the suitability of the CBD method extracting the three tracers with an averagerecovery rate of 0.7. The analysis of the iron content of soil and sediment samples indicates arelatively low movement of soil although showing significant statistical differences withbackground and mixture values. These results are in line with the ones detected by the magneticsusceptibility measurements. Further textural and visible spectrum analysis of the samples willallow to determine the possible selectivity factor and to discriminate qualitative and quantitativelyhematite and goethite tracers, respectively.

Traditionally, soil quality has been assessed through physical, chemical and biological properties without paying attention to soil biota and the different associated ecosystem services provided (Tyler, 2019). To fill that gap, the european BiodivERsA “SoilMan” project (Ecosystem services driven by the diversity of soil biota – understanding and management in agriculture) is focused on the relations among soil management, soil biodiversity, and ecosystem services, at seven different management gradients in agricultural long term observations (LTO’s) trials across Europe (France “SOERE-PROs EFELE” and “SOERE-ACBB Lusigan”, Romania “Turda”, Sweden “Angermanland” and “Säby-Uppland”, Germany “Garte Süd” and Spain “La Hampa”). Management gradients covered different tillage regimes (zero, minimum and conventional) and different crop rotations (crop types and duration).In the present study, we characterised the bacterial and fungal communities of soils from the different countries and agricultural managements in arable land. The samplings were carried out following the same methodology in all the countries during 2017-2018 when wheat was sown in the LTO’s. The soil DNA was extracted and subjected to metabarcoding analysis of 16S and Internal Transcribed Spacer (ITS) ribosomal RNA (rRNA) for bacterial and fungal community analysis, respectively.Different alpha diversity metrics, including number of OTUs, Simpsons and Shannon indexes, as well as beta diversity distances (weighted and unweighted UNIFRAC, Jaccard and Bray-Curtis) were calculated. Multidimensional Scaling ordination plots (PCoA) were used to visualize the existence of community gradients among locations and soil managements. All the statistical data procedure was analysed using the vegan R package (Oksanen, 2011).In general terms, results show that alpha diversity for both bacteria and fungi, clearly differs among countries while soil management effects are less defined among and within countries. Concerning the beta diversity indexes, communities tend to cluster more according to the spatial location than due to the soil management regimen. This is especially true for fungal communities. Further analysis will identify possible correlations of bacterial and fungal communities with environmental variables and other physicochemical and biological soil properties.References:Oksanen, J. (2011). Multivariate Analysis of Ecological Communities in R: vegan tutorial.Tyler, H. L. (2019). Bacterial community composition under long-term reduced tillage and no till management. Journal of Applied Microbiology, 126(6), 1797–1807. https://doi.org/10.1111/jam.14267

The use of cover crops has been prescribed as a mitigation measure for offsite contamination, as they reduce sediment and agrochemical loads, thus reducing the hydrological connectivity of the land. However, there is the need to quantify its effectiveness for specific agrochemicals in broader range of conditions, to validate management for its safe environmental use. The objectives of the present study were: (1) to explore the use of simulated rainfall and magnetic iron oxide to understand the impact of vegetation strips on runoff and soil losses at the plot scale and, (2) to evaluate the effectiveness of vegetation strips in buffering sediment and herbicides coming from bare soil areas. The study encompasses six sets of rainfall simulations (three replications each) under four different soil management scenarios: dry vegetation cover sowed that year, dry vegetation cover two years after sowing, freshly-tilled soil, and tilled soil with a compacted surface due to rainfall and trampling. The experiments involved the use of a magnetic iron oxide as a sediment tracer to obtain a better understanding of the trapping efficiency of the vegetation strips. Three runoff plots were established on a hillslope under a Fluvisol alluvial terrace. Each of the plots contained three bare areas tagged with magnetic iron oxide and three strips with Lolium multiflorum L. The results indicate that by using cover crop strips, runoff and sediment losses were approximately 20% and 4%, respectively, of the losses measured in the bare compacted soil, while losses on the freshly-tilled surface were similar to that of the cover crop. Herbicide losses were greatly reduced by the cover crops, with losses ranging from approximately 0.1%–0.6% of the doses applied the day before on the bare area. Nevertheless, on the compacted bare soil, terbuthylazine, oxyfluorfen and diflufenican losses were 1.63%, 4.35% and 9.67%, respectively, of the dose applied the previous day. This can be explained because the tilled and compacted soil showed the highest cumulative runoff and soil losses values (28 mm and 248.9 g m −2 ). The formation of micro-relief steps after the first simulation reduced the hillslope connectivity and, thus, the soil losses and runoff. Tracer selectivity from soil textures with fine particle size (clay) was observed, as there was an enrichment of these particles in the collected sediment. This study quantified the impact of cover crop strips on mitigating offsite herbicide contamination and improved our understanding of sediment redistribution at the hillslope scale.

The perception of landscape and consumption behaviour in relation to landscape was estimated using a questionnaire-based survey with 17 photographs: 15 photos from Romanian representative landscape units, 1 photo representing a foreign landscape (Hungary), and 1 marketing photo. The photo documentation was conducted in sixteen vineyards ecosystems from Târnave Viticultural Region - Transylvania (NW-Romania). The most representative landscape was the photo that had the specifications and criteria: low practices intensity with low landscape complexity; and the less representative landscape was the photo that had the specifications and criteria: photo capturing hiking, walking, tourism, and recreational activities in a viticulture landscape. The landscape could influence the following aspects of communities’ livelihood: establishments and development of enterprises, tourism and recreation businesses, and the place to live. The words used by interviewed people to point out the landscape were interpreted from the point of view of the concept of multifunctionality.

Alternative management practices such as no-tillage compared to conventional tillage are expected to recover or increase soil quality and productivity, even though all of these aspects are rarely studied together. Long-term field experiments (LTEs) enable analysis of alternative management practices over time. This study investigated a total of 251 European LTEs in which alternative management practices such as crop rotation, catch crops, cover crops/green manure, no-tillage, non-inversion tillage and organic fertilization were applied. Response ratios of indicators for soil quality, climate change and productivity between alternative and reference management practices were derived from a total of 260 publications. Both positive and negative effects of alternative management practices on the different indicators were shown and, as expected, no alternative management practice could comply with all objectives simultaneously. Productivity was hampered by non-inversion tillage, FYM amendments and incorporation of crop residues. SOC contents were increased significantly following organic fertilizers and non-inversion tillage. GHG emissions were increased by slurry application and incorporation of crop residues. Our study showed that alternative management practices beneficial to one group of indicators (e.g. organic fertilizers for biological soil quality indicators) are not necessarily beneficial to other indicators (e.g. increase of crop yields). We conclude that LTEs are valuable for finding ways forward in protecting European soils as well as finding evidence-based alternative management practices for the future; however, experiments should focus more on biological soil quality indicators as well as GHG emissions to enable better evaluation of trade-offs and mutual benefits of management practices.

Trabajo presentado en la European Geosciences Union General Assembly (EGU 2017), celebrada en Viena del 23 al 28 de abril de 2017., In undulating arable landscapes tillage erosion is one of the dominant processes initiating lateral transfer of soil and soil constituents. Especially, in relatively dry regions, where tillage erosion can be much larger than water erosion, the associated changes in soil hydraulic properties might have substantial effects upon the sustainable use of soil resources. There have been some studies using different techniques to determine tillage erosion which build the basis for tillage erosion modelling approaches. However, tillage erosion is rather understudied compared to water erosion. The goal of this study was to bring together experts using different techniques to determine tillage erosion in an experimental set-up and to analyse the different results and assess the uncertainties associated with typical model inputs. Tillage erosion on a 50 x 10 m plot was determined after two phases of seven tillage passes performed within a week (simulating 10-14 yrs of tillage). As tracers, two different micro-tracers (magnetite mixed with soil and fluorescent sand) and one macro-tracer (passive Radio-Frequency Identification (RFID) transponders; dia. 3 mm, length 20 mm) were used. Moreover, tillage induced changes in topography were spatially determined for the entire plot with two different terrestrial laser scanners and an UAV-based structure by motion topography analysis. Topography changes were also evaluated at 12 points using buried concrete flagstones as reference. A preliminary analysis of tracer movement indicates substantial differences in tillage induced translocation depending on type of tracer. While the mean translocation of the RFIDs was 0.47 m per pass the mean movement of the micro-tracers was 0.70 m. Substantial differences were also found for the different techniques to determine changes in topography. Overall the experiment underlines the importance of tillage erosion for the lateral transfer of soil and soil constituents, but also shows the large discrepancies between measurements based on different techniques. The latter introduces substantial uncertainties in any existing tillage erosion modelling approach.

Vineyards show some of the largest erosion rates reported in agricultural areas in Europe. Reported rates vary considerably under the same land use, since erosion processes are highly affected by climate, soil, topography and by the adopted soil management practices. Literature also shows differences in the effect of same conservation practices on reducing soil erosion from conventional, bare soil based, management. The Revised Universal Soil Loss Equation (RUSLE) is commonly adopted to estimate rates of water erosion on cropland under different forms of land use and management, but it requires proper value of soil cover and management (C) factors in order to obtain a reliable evaluation of local soil erosion rates. In this study the ORUSCAL (Orchard RUSle CALibration) is used to identify the best calibration strategy against long-term experimental data. Afterwards, ORUSCAL is used in order to apply the RUSLE technology from farm based information across different European wine-growing regions. The results suggest that the best strategy for calibration should incorporate the soil moisture sub-factor (Sm) to provide better soil loss predictions. The C factor, whose average values ranged from 0.012 to 0.597, presented a large spatial variability due to coupling with local climate and specific local management. The comparison across the five wine-growing regions indicates that for the soil protection management, permanent cover crop is the best measure for accomplishing sustainable erosion rates across the studied areas. Alternate and temporary cover crops, that are used in areas of limited water resources to prevent competition with vines, failed to achieve sustainable erosion rates, that still need to be addressed. This raises the need for a careful use of C values developed under different environmental conditions., This study was funded by the European BiodivERsA project VineDivers (https://short.boku.ac.at/vinedivers) through the BiodivERsA/FACCE JPI (2013–2014 joint call) for research proposals, with the national funders: Austrian Science Fund (grant numbers I 2044-/I 2043-/I 2042-B25 FWF), French National Research Agency (ANR), Spanish Ministry of Economy and Competitiveness (PCIN-2014-098), Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCDI) and Federal Ministry of Education and Research (BMBF/Germany). Also to the CNR Short Term Mobility Program 2016 for funding a stay at IAS-CSIC during which M.Biddoccu contributed to this study and the SHui project funded by the European Commission (GA 773903), which supported the final steps of the analysis presented in this manuscript.

A number of policies proposed to increase soil organic matter (SOM) content in agricultural land as a carbon sink and to enhance soil fertility. Relations between SOM content and crop yields however remain uncertain. In a recent farm survey across six European countries, farmers reported both their crop yields and their SOM content. For four widely grown crops (wheat, grain maize, sugar beet and potato), correlations were explored between reported crop yields and SOM content (N = 1264). To explain observed variability, climate, soil texture, slope, tillage intensity, fertilisation and irrigation were added as co-variables in a linear regression model. No consistent correlations were observed for any of the crop types. For wheat, a significant positive correlation (p < 0.05) was observed between SOM and crop yields in the Continental climate, with yields being on average 263 ± 4 (95% CI) kg ha higher on soils with one percentage point more SOM. In the Atlantic climate, a significant negative correlation was observed for wheat, with yields being on average 75 ± 2 (95%CI) kg ha lower on soils with one percentage point more SOM (p < 0.05). For sugar beet, a significant positive correlation (p < 0.05) between SOM and crop yields was suggested for all climate zones, but this depended on a number of relatively low yield observations. For potatoes and maize, no significant correlations were observed between SOM content and crop yields. These findings indicate the need for a diversified strategy across soil types, crops and climates when seeking farmers’ support to increase SOM., Data collection for this publication was financially supported by the European Commission under the CATCH-C project (Grant Agreement N° 289782) within the 7th Framework Programme for Research, Technological Development and Demonstration. Its content does not represent the official position of the EC and is entirely the responsibility of the authors.

Trabajo presentado en el 172nd EAAE Seminar ("Agricultural policy for the environment or environmental policy for agriculture"), celebrado en Bruselas el 28 y 29 de mayo de 2019., Vine cultivation on slopescauses serious erosion with significant losses of nutrients, organic matter and water, followed by an overall loss of soil biodiversity and ecosystem services (ES). Cover crops (CC) in inter-rows can reduce these effects, but are often renounced by winegrowers due to economic causes. Soil erosion rates which were obtained from field data and simulations with ORUSCAL (Orchard RUSle CALibration) lay the basis for comparing three different scenarios of soil management; conventional tillage (CT), temporary cover crops (TCC) and permanent cover crops (PCC). We use the Policy Analysis Matrix (PAM) to include on-and off-side costs oferosion and to demonstrate their economic implications. The scenarios are calculated for two different European wine regions, Montilla-Moriles (Spain) and Carnuntum (Austria). Results from ORUSCAL show that erosion is decreased in most cases with increasing use of vegetation cover. Overall, the consideration of erosion costs in the budget of farmers has only minor effects on their competitiveness and additional costs for CC are not covered by private erosion cost savings. However, if social erosion costs are added, CC are cost-effective in both regions. This is even without the valuation of non-marketed ecosystem services such as cultural and aesthetic aspects which most likely will increase social costs of erosion. Furthermore, our results show that higher revenues are of greater importance for management decisions than lower input prices. Therefore, CC should be rewarded either through a higher willingness to pay from consumers or government support., This work contributes to the VineDivers Project (01LC1401A) and the authors are grateful for the financial support through the 2013/14 BiodivERsA/FACCE-JPI joint call for research proposals and the Federal Ministry of Education and Research.

This study compares the distribution of bulk soil organic carbon (SOC also reported as Corg), its fractions (unprotected, physical, chemical and biochemically protected), available P (Pavail), organic nitrogen (Norg) and stable isotopes (δ15N and δ13C) signatures at four soil depths (0–10, 10–20, 20–30, 30–40 cm) between a nearby forested reference area and an historical olive orchard (established in 1856) located in Southern Spain. In addition, these soil properties, as well as water stable aggregates (Wsagg) were contrasted at eroding and deposition areas within the olive orchard, previously determined using 137Cs. Results highlight a significant depletion of SOC stock in the olive orchard as compared to the forested area, approximately 120 vs. 55 t C ha−1 at the top 40 cm of soil respectively, being severe in the case of unprotected carbon fraction. Erosion and deposition within the old olive orchard created large differences in soil properties along a catena, resulting in higher Corg, Pavail and Norg contents and δ15N at the deposition area and therefore defining two areas with a different soil quality status (degraded vs. non-degraded). Differences in δ15N at such different catena locations suggest that this isotopic signature has the potential for being used as an indicator of soil degradation magnitude, although additional studies would be required to confirm this finding. These overall results indicate that proper understanding of Corg content and soil quality in olive orchards require the consideration of the spatial variability induced by erosion/deposition processes for a convenient appraisal at farm scale.

Agricultural soils with too little soil organic matter (SOM) content are characterized by fertility problems. A number of authors have tried to specify threshold values for SOM content to indicate what is ‘too little’, ranging from 1 to 5%, below which yields may be affected. How much SOM content is sufficient, however, depends on a number of environmental factors. In addition, up to date farmers’ perceptions were not included when developing thresholds. Therefore, this study focuses on the following three objectives: (1) to identify a risk indicator on SOM deficiency based on environmental factors and agricultural land use; (2) to test the risk indicator using farmers’ perceptions and (3) to establish threshold values for SOM content based on farmers’ perceptions. For objective 1, literature was reviewed on effects of environmental factors and land use on SOM deficiency. Findings were combined into nine options for a risk indicator on SOM deficiency, mapped at European scale. For objective 2, a farm survey was done among 1452 arable farmers in five European countries (Belgium, Germany, Austria, Spain and Italy). Associations between perceived deficiency of SOM by farmers and environmental factors, land use and the risk indicator were investigated. For objective 3, farmers’ perceptions on SOM deficiency were related to the average SOM content of their fields. Mapping the risk indicator at European scale gives a high to very high risk of SOM deficiency for 7 to 37% of European agricultural land, mainly located in Southern and Eastern Europe. Of the farmers in our survey, 18% perceived a high to very high SOM deficiency. A weak correlation was found between the risk indicator and farmers’ perceptions of SOM deficiency (0.15-0.18, Spearman’s rank correlation). Stronger relations were found between separate environmental factors and perceived SOM deficiency. Apparently, having a more extreme environmental condition for one factor gives a higher chance of perceiving a deficiency of SOM than a combination of moderate environmental conditions. Based on farmers’ perceptions threshold intervals for SOM content were established (sand: 1.2–4.7%, loam: 0.6–2.6% and clay: 1.0–2.4%). If policies on SOM management want to include benefits for productive capacity, targeting areas with a relatively high risk of SOM deficiency, more extreme environmental conditions or with very low SOM contents (below the given threshold intervals) seems most promising.

Conventional tillage (CT) and cover crops (CC) trigger different runoff (Q) and runon (Qin) magnitudes and patterns in woody crops. The spatial and temporal stability of these patterns is not well known yet. In this study, we run the uncalibrated DR2-2013© SAGA v1.1 model (0.5 × 0.5 m of cell size) to simulate time to ponding (Tp), runoff duration (TQ), initial runoff per raster cell (q0), Qsim and Qin in six olive plots (480 m2 per plot) during two years (108 rainfall events and 648 simulations). Two plots were managed with a mixture of plant species (CC-I), two with one single plant species (CC-II) and two with CT. Runoff yield from each plot was collected (Qobs) in gauging-stations during 27 time-integrated samples and used for modelling validation (162 control points). On average, Qobs was 9% higher under CT than under CC-I, and 8% higher than under CC-II. Topsoil saturation was simulated for the entire plots during 29 events (test-period), and Qsim appeared in another 51 and 52 events in the plots with CC and CT. Tp with CT was 2.3 times higher (59 s) than the average duration with CC and the topsoil became saturated 3.3 times faster in the inter-rows than below the trees. Values of q0 with CC were 2.3% lower than with CT and total Qsim with CC was 2% higher than with CT. However, the differences of Qsim between the different treatments were not statistically significant. The mean observed and simulated runoff coefficients were of 11 and 14%, with median values of 7 and 10%. Qsim correlated well with Qobs (Pearson ca. 0.861), and Qsim was overestimated ca. 10%. The model performed better when rainfall depth and intensity were high, and the range of variability of both Qsim and Qobs was similar. The average, best and worst Nash–Sutcliffe coefficients were 0.665, 0.791 (P6) and 0.512 (P3) and thus model simulations were satisfactory. The four plots with CC presented on average a worse performance (Kling–Gupta coefficient = 0.607) than the two plots with CT (KGE = 0.769). The lowest spatial variability of q0, Qobs, Qsim and actual available water (Waa, the sum of Qin and stored water in the soil surface) were found in the plots with CC. CT triggered higher spatial variability of runoff and higher temporal variability of runon than CC., The postdoctoral contract of Dr. López-Vicente and part of this research was funded by the project “Soil and organic carbon loss and redistribution in olive groves of Jaen, Granada and Seville: numerical simulation and assessment of the particle size effect” of the University of Jaen (group RNM296) (Spain), the Regional Government of Andalusia (Spain) and the European Union (FEDER funds). The experimental results from the runoff plots has been possible since 2009 through projects Biosuelo, P08-AGR-03643 (Andalusian Government), RESEL (Spanish Ministry for Environment and Rural and Marine Affairs) and FEDER funds.

Spontaneous grass covers are an inexpensive soil erosion control measure in olive orchards. Olive farmers allow grass to grow on sloping terrain to comply with the basic environmental standards derived from the Common Agricultural Policy (CAP, European Commission). However, to date there are few studies assessing the environmental quality considering such covers. In this study, we measured biodiversity indices for spontaneous grass cover in two olive orchards with contrasting site conditions and management regimes in order to evaluate the potential for biodiversity metrics to serve as an indicator of soil degradation. In addition, the differences and temporal variability of biodiversity indicators and their relationships with environmental factors such as soil type and properties, precipitation, topography and soil management were analysed. Different grass cover biodiversity indices were evaluated in two olive orchard catchments under conventional tillage and no tillage with grass cover, during 3 hydrological years (2011–2013). Seasonal samples of vegetal material and photographs in a permanent grid (4 samples ha−1) were taken to characterize the temporal variations of the number of species, frequency of life forms, diversity and modified Shannon and Pielou indices. Sorensen's index showed strong differences in species composition for the grass covers in the two olive orchard catchments, which are probably linked to the different site conditions. The catchment (CN) with the best site conditions (deeper soil and higher precipitation) and most intense management presented the highest biodiversity indices as well as the highest soil losses (over 10 t ha−1). In absolute terms, the diversity indices of vegetation were reasonably high for agricultural systems in both catchments, despite the fact that management activities usually severely limit the landscape and the variety of species. Finally, a significantly higher content of organic matter in the first 10 cm of soil was found in the catchment with worse site conditions in terms of water deficit, average annual soil losses of 2 t ha−1 and the least intense management. Therefore, the biodiversity indices considered in this study to evaluate spontaneous grass cover were not found to be suitable for describing the soil degradation in the study catchments.

Although soil erosion is one of the main threats to agriculture sustainability in many areas of the world, its processes are difficult to measure and still need a better characterization. The use of iron oxides as sediment tracers, combined with erosion and mixing models opens up a pathway for improving the knowledge of the erosion and redistribution of soil, determining sediment sources and sinks. In this study, magnetite and a multivariate mixing model were used in rainfall simulations at the micro-plot scale to determine the source of the sediment at different stages of a furrow–ridge system both with (+T) and without (–T) wheel tracks. At a plot scale, magnetite, hematite and goethite combined with two soil erosion models based on the kinematic wave approach were used in a sprinkler irrigation test to study trends in sediment transport and tracer dynamics along furrow lengths under a wide range of scenarios. In the absence of any stubble cover, sediment contribution from the ridges was larger than the furrow bed one, almost 90%, while an opposite trend was observed with stubble, with a smaller contribution from the ridge (32%) than that of the bed, at the micro-plot trials. Furthermore, at a plot scale, the tracer concentration analysis showed an exponentially decreasing trend with the downstream distance both for sediment detachment along furrows and soil source contribution from tagged segments. The parameters of the distributed model KINEROS2 have been estimated using the PEST Model to obtain a more accurate evaluation. Afterwards, this model was used to simulate a broad range of common scenarios of topography and rainfall from commercial farms in southern Spain. Higher slopes had a significant influence on sediment yields while long furrow distances allowed a more efficient water use. For the control of runoff, and therefore soil loss, an equilibrium between irrigation design (intensity, duration, water pattern) and hydric needs of the crops should be defined in order to establish a sustainable management strategy., This work was funded by the Spanish Ministry of Science and Innovation (Projects AGL2006-10927-C03-01, AGL2006-10927-C03-02 and AGL2009-12936-C03-01), the Project P09-AGR-4782 of the Consejería of Economy, Innovation and Science of the Junta de Andalucía, and FEDER funds.

A 3-year experiment compared in an olive orchard the effect of different cover crops’ composition on runoff, water erosion, diversity of annual plants, and arthropod communities which could provide an alternative to conventional management based on tillage (CT). The cover crops evaluated were a seeded homogeneous grass (GC), a seeded mix of ten different species (MC), and a non-seeded cover by vegetation naturally present at the farm after 20 years of mowing (MC). The results suggest that heterogeneous cover crops can provide a viable alternative to homogeneous ones in olives, providing similar benefits in reducing runoff and soil losses compared to management based on bare soil. The reduction in soil loss was particularly large: 46.7 in CT to 6.5 and 7.9 t ha year in GC and MC, respectively. The heterogeneous cover crops resulted in greater diversity of plant species and a modification of the arthropod communities with an increased number of predators for pests. The reduction of the cost of implanting heterogeneous cover crops, improvement of the seeding techniques, and selection of species included in the mixes require additional research to promote the use of this practice which can deliver enhanced environmental benefits., This study has been possible thanks to the support of Syngenta from 2002 to 2013, through projects ProTerra I, II and Biosuelo. Since 2009, some additional measurements and analysis have been possible to support by the projects P08-AGR-03643, P12-AGR-931, AGL2015-65036-C3-1, RESEL (Spanish Ministry for Environment and Rural and Marine Affairs), and FEDER funds. We also want to acknowledge the contribution of three anonymous reviewers who had helped greatly to improve the quality of the original manuscript.

El desarrollo de las tecnologías de la información y la comunicación (TIC) ha permitido el surgimiento de herramientas didácticas en el campo de la educación, proporcionando herramientas prácticas para apoyar a las clases presenciales. En este contexto, los sistemas electrónicos de respuesta estudiantil pueden ser útiles para introducir un elemento tecnológico motivador en las lecciones, así como una nueva metodología. En este estudio, además del uso de los sistemas de respuesta interactiva o clickers, se ha introducido la tecnología de aprendizaje móvil mediante la elaboración de una metodología de uso de las herramientas Kahoot y Telegram en la asignatura "Fundamentos Físicos en la Ingeniería II" del Grado en Ingeniería Electrónica Industrial. El Departamento de Física Aplicada de la Universidad de Córdoba tiene una amplia experiencia en el uso de Clickers en clases teóricas con grupos grandes para diferentes grados universitarios, pero ahora el uso de tecnologías móviles de aprendizaje se ha introducido en grupos de tamaño medio para clases prácticas. Usando esta nueva metodología, los estudiantes de grupos medianos realizan un cuestionario durante la lección de resolución de problemas, donde utilizaron sus conocimientos adquiridos durante la clase. La realización del cuestionario permite a los profesores evaluar en tiempo real el nivel del estudiante y utilizar la retroalimentación para abordar los problemas iniciales y los malentendidos. Los resultados muestran que los sistemas de respuesta interactiva son altamente valorados por los estudiantes, que lo perciben como una herramienta para mejorar el aprendizaje y aumentar la competencia en el aula. The development of information and communication technologies (ICT) has enabled the emergence of teaching tools in the education field, providing practical tools to support face-to-face classes. In this context, electronic student response systems can be useful for introducing a motivating technological element into the lessons, as well as a new methodology. In this study, in addition to the use of interactive response systems or clickers, mobile learning technology has been introduced by developing a methodology for using the Kahoot and Telegram tools in the subject “Physical Foundations of Engineering II” of Electronic Engineering Degree. Department of Applied Physics of University of Cordoba has a broad experience using Clickers in theory classes with large groups for different university degrees, but now the use of mobile learning technologies has been introduced in medium-sized groups for practical classes. Using this new methodology, students of medium-sized groups perform a quiz during the problem solving lesson, where they utilized their knowledge gained during the class. The completion of the quiz allows teachers to assess the student’s level in real time, and to use the feedback to address initial problems and misunderstandings. Results show the interactive response systems are highly valued by students, who perceive it as a tool to improve learning and increase competition in the classroom.

At the global scale, vineyards are usually managed intensively to optimize wine production without considering possible negative impacts on biodiversity and ecosystem services (ES) such as high soil erosion rates, degradation of soil fertility or contamination of groundwater. Winegrowers regulate competition for water and nutrients between the vines and inter-row vegetation by tilling, mulching and/or herbicide application. Strategies for more sustainable viticulture recommend maintaining vegetation cover in inter-rows, however, there is a lack of knowledge as to what extent this less intensive inter-row management affects biodiversity and associated ES. We performed a hierarchical meta-analysis to quantify the effects of extensive vineyard inter-row vegetation management in comparison to more intensive management (like soil tillage or herbicide use) on biodiversity and ES from 74 studies covering four continents and 13 wine-producing countries. Overall, extensive vegetation management increased above- and below-ground biodiversity and ecosystem service provision by 20% in comparison to intensive management. Organic management together with management without herbicides showed a stronger positive effect on ES and biodiversity provision than inter-row soil tillage. Soil loss parameters showed the largest positive response to inter-row vegetation cover. The second highest positive response was observed for biodiversity variables, followed by carbon sequestration, pest control and soil fertility. We found no trade-off between grape yield and quality vs. biodiversity or other ES. Synthesis and applications. Our meta-analysis concludes that vegetation cover in inter-rows contributes to biodiversity conservation and provides multiple ecosystem services. However, in drier climates grape yield might decrease without irrigation and careful vegetation management. Agri-environmental policies should therefore focus on granting subsidies for the establishment of locally adapted diverse vegetation cover in vineyard inter-rows. Future studies should focus on analysing the combined effects of local vineyard management and landscape composition and advance research in wine-growing regions in Asia and in the southern hemisphere., We thank all authors who provided additional data and information on request of the authors of this study. We sincerely thank three anonymous reviewers and the Associate Editor Peter Manning for their constructive comments. This meta- analysis was conducted in the course of the project VineDivers (www.vinedivers.eu) funded through the 2013–2014 BiodivERsA/FACCE- JPI joint call for research proposals, with the national funders: Austrian Science Fund (FWF) (I 2044-B25), Spanish Ministry for Economy and Competitiveness (MINECO), French National Research Agency (ANR), Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCDI) and Federal Ministry of Education and Research (BMBF/Germany). P.B. was supported by the German Research Foundation (DFG BA4438/2- 1) and by the Economic Development and Innovation Operational Programme of Hungary (GINOP–2.3.2–15–2016–00019).

[Departement_IRSTEA]Territoires [TR1_IRSTEA]DTAM [Axe_IRSTEA]DTAM2-ACPUB; International audience; This paper analyses soils-related policies in Europe and in selected member states and regions. Our approach breaks down policy packages at European, national and regional levels into strategic objectives, operational objectives, policy measures and expected impacts, and assesses the relationships between these elements and soil stakes. Four major policy packages, both at EU and national level (CAP-I, RDP, Environment, national initiatives) were analysed. A numerical scale was developed to quantify the level of “embeddedness” of soil stakes in these policy packages. We found that countries better embed soil stakes into their policies when they also put more efforts on environmental innovation. In turn, countries with a high embeddedness level, with high trust in European institutions and that make more efforts towards renewable energy, tend to propose a wider variety of management practices to farmers for dealing with soil stakes.

To evaluate the agronomic value of animal manure, we quantified the effects of pedo-climatic, crop and management factors on crop productivity, N use efficiency, and soil organic matter, described with simple indicators that compare manures with mineral fertilizers. We selected 80 European long-term field experiments that used bovine farmyard manure or bovine liquid slurry, alone (FYM and SLU) or combined with mineral fertilizers (FYMm and SLUm), and compared them to mineral fertilizer only reference treatments. We collected 5570 measurements from 107 papers. FYM produced slightly lower crop yields (−9.5%) when used alone and higher (+11.3%) yields when used in combination with N fertilizer (FYMm), compared to those obtained using mineral fertilizers only. Conditions promoting manure-N mineralization (lighter soil texture, warmer temperature, longer growing season, and shallower incorporation depth) significantly increased the effect of FYM/FYMm on crop yield and yield N. The production efficiency of FYM (yield:N applied ratio) was slightly lower than that of mineral fertilizers (-1.6%). The apparent N recoveries of FYM and FYMm were 59.3% and 78.7%, respectively, of mineral fertilizers. Manured soils had significantly higher C (+32.9% on average for FYM and FYMm) and N (+21.5%) concentrations. Compared to mineral fertilizers, yield was reduced by 9.1% with SLU, but not with SLUm. Influencing factors were similar to those of FYM/FYMm. Efficiency indicators indicated SLU (but not SLUm) was less effective than mineral fertilizers. Slurry significantly increased SOC (on average for SLU and SLUm by +17.4%) and soil N (+15.7%) concentrations. In conclusion, compared to mineral N fertilizers, bovine farmyard manure and slurry were slightly less effective on the crop, but determined marked increases to SOC and soil N, and thus, to long-term soil fertility maintenance.

Since prehistoric times, farmers have faced the challenge of balancing the demand for increasing food production from existing soil resources with conservation of these resources. Land use change from natural vegetation to agricultural land and intensification of agricultural soil management are closely linked to increased rates of soil erosion. This review analyzed and quantified the effects of changes in past land use and agricultural soil management on soil erosion. At a global scale, the period of the first significant land use change closely corresponds to a first wave of soil erosion. Equally important, however, are changes in past soil management. As shown by numerous case studies, changes in management under the same land use can convert sustainable agroecosystems into highly degraded systems. As soil erosion rates, soil profile truncation, agricultural yield, and biomass production are closely related, considering the interactions and feedback effects is important when modelling this system. This paper shows how modelling the dynamics of past soil erosion and agricultural sustainability raises similar challenges to those of quantifying future changes in climate or agricultural systems., This research was funded under the research projects “AGL2012-40128-C03-01”,“AGL2012-40128-C03-02” and “AGL2012-40128-C03-03”. The first author is grateful for the funding by the Ministry of Economy and Competitiveness under the Ramon y Cajal Fellowship programme.

Dissolved organic C (DOC) and dissolved reactive P (DRP) in runoff and total organic C (TOC) and total P (TP) in sediment were measured in three olive (Olea europaea L. ) orchards, during a 3-yr runoff plot experiment under two soil management systems (temporary cover crop in lanes [CC]; conventional tillage [CT]). Losses of DOC (7.8–13.6 kg ha−1 yr−1) were equivalent and losses of TOC (101–432 kg ha−1 yr−1) were higher than those measured in other agricultural systems, so both sources of organic C, dissolved and in sediment, should not be neglected when accounting fluxes to water bodies in the region and soil organic C (SOC) balances at the hillslope scale in olive orchards. Losses of DRP (0.03–0.21 kg ha−1 yr−1) were in the lower to medium range, while losses of TP (2–39 kg ha−1 yr−1) were in the higher range than those reported from agricultural areas. The average annual concentration of DOC in runoff was similar for both systems (20.9–9.1 vs. 21.4–8.7 mL L−1 for CC and CT, respectively) and also for DRP (0.45–0.02 vs. 0.20–0.02 mg L−1 for CC and CT, respectively). Concentrations of TOC and TP were higher under CC, but under CC the TOC and TP fluxes were lower because of reduced sediment losses. To achieve a large reduction in TP and TOC, CC management should provide early ground cover beginning in early fall, the start of the rainy season. A conceptual model of TOC and TP losses was developed to estimate the impact of different cover crop soil conservation strategies., This study was supported by Projects P08-AGR-03643, P11 AGR-7431, P12-AGR-931 (Andalusian Government), AGL2012-40128-C03-01 and AGL2015-65036-C3-1 (Spanish Government), and FEDER funds. The long-term experiment at Benacazón was also supported by Syngenta through Project BIOSUELO. We gratefully acknowledge this support.

Introduction: Interest in the use of sediment tracers as a tool to complement traditional water erosion or deposition measurements has increased due to the additional information they provide, such as sediment source identification, tracking of sediment movement across the landscape at various temporal and spatial scales, and estimation of soil erosion rates. For these reasons, the utility and robustness of sediment tracing approaches using a wide range of substances and soil properties have been evaluated in numerous studies. Conclusions: A review of established tracing approaches identified five distinct groups of tracing approaches: fallout radionuclides, rare earth elements, soil magnetism and magnetic substances, other tracers, and sediment fingerprinting techniques. This paper describes the basic theory of each tracing approach in assessing soil erosion and sediment redistribution, describing their methodology and main applications, and summarizing the commonalities and differences between the approaches. It also identifies research gaps and future trends. © 2013 Springer-Verlag Berlin Heidelberg., This study was initiated while one of the authors was on an exchange program supported by a fellowship of the OECD Cooperative Research Program in Biological Resource Management for Sustainable Agricultural System. This support, as well as the one provided by the Spanish Ministry of Science and Innovation through Projects AGL2006-10927-C03-01, AGL2009-12936-C03-01 and FEDER funds, is gratefully acknowledged.

Trabajo presentado en la 4th MC meeting and WG meetings (Connecteur), celebrado en Praga del 21 al 23 de septiembre de 2016., The knowledge of water erosion processes is essential when predicting the effects of soil conservation struc- tures aimed to disrupt connectivity in sediment transport across the landscape. Experiments (field and laboratory) measuring the overall effect of these structures and model analysis are usually the techniques used to evaluate their effectiveness. The use of sediment tracers is an attractive tool to complement those technologies. During the last years a tracer methodology based on the application of iron oxides as magnetite, hematite and goethite to the top soil profile has been evaluated. The use of these iron oxides as sediment traces has been validated in laboratory and field experiments. They have been employed, afterwards, to monitor preferential flows, identify sources of sediments, quantify medium term erosion rates and to map soil redistribution within agricultural fields due to erosion and deposition. Despite of their limitations (to be discussed in the presentation) they provide useful information to evaluate the efficiency of water conservation measurements such as grass strips or stone bunds to optimize their imple- mentation and to calibrate parameters for improving the accuracy of soil erosion models, and therefore to extrapolate their results to larger spatial and temporal scales.

Winter, Silvia et al.-- Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 12 al 17 de abril de 2015., La Conchuela is an olive orchard catchment of 8.0 ha located in Córdoba (southern Spain) where runoff and sediment losses have been measured at hillslope and catchment scale since 2006. Three different ap- proaches were used to evaluate the behavior of sediment displacement within and from the catchment: soil properties and water erosion and, sediment tracers. During the hydrological year 2010-2011, runoff and soil loss were measured at plot and catchment scale. Chemical (organic carbon and available phosphorus) and physical (particle size distribution) properties were determined in the top 5 cm of the soil and in the sediment collected at plot and catchment scale. Both set of measures were grouped and compared distinguishing between zones (lanes and tree rows) and scales (plot and catchment scale). Finally, these results were compared to the ones obtained using magnetite at hillslope scale regarding soil redistribution after rainfall events during 2008-2010. This study presents a preliminary characterization of the environmental processes occurring during water erosion events to identify significant sources of sediment at hillslope scale and their comparison to the catchment outlet in order to implement local soil and water conservation measures improving their efficiency and therefore reducing the costs associated to them.

Spontaneous grass covers are an inexpensive soil erosion control measure in olive orchards. Olive farmers allow grass to grow on sloping terrain to comply with the basic environmental standards derived from the Common Agricultural Policy (CAP). However, to date there are very few studies assessing the environmental quality and extent of such covers. In this study, we described and compared the biodiversity indicators associated to herbaceous vegetation in two contrasting olive orchards in order to evaluate its relevance and quality. In addition, biodiversity patterns and their relationships with environmental factors such as soil type and properties, precipitation, topography and soil management were analyzed. Different grass cover biodiversity indices were evaluated in two olive orchard catchments under conventional tillage and no tillage with grass cover, during 3 hydrological years (2011–2013). Seasonal samples of vegetal material and pictures in a permanent grid (4 samples ha−1) were taken to characterize the temporal variations of the number of species, frequency, diversity and transformed Shannon's and Pielou's indices. Sorensen's index obtained in the two olive orchard catchments showed notable differences in composition, probably linked with the different site conditions. The catchment with the best site conditions (deeper soil and higher precipitation), with average annual soil losses over 10 t ha−1 and a more intense management, presented the highest biodiversity indices. In absolute terms, the diversity indices were reasonably high in both catchments, despite the fact that agricultural activity usually severely limits the landscape and the variety of species. Finally, a significantly higher content of organic matter in the first 10 cm of soil was found in the catchment with the worst site conditions, average annual soil losses of 2 t ha−1 and the least intense management. Therefore, the biodiversity indicators associated to weeds were not found to be suitable for describing the soil degradation in the study catchments.