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16 Pags.- 12 Figs.- 8 Tabls., Soil erosion can present a major threat to agriculture due to loss of soil, nutrients, and organic carbon. Therefore, soil erosion modelling is one of the steps used to plan suitable soil protection measures and detect erosion hotspots. A bibliometric analysis of this topic can reveal research patterns and soil erosion modelling characteristics that can help identify steps needed to enhance the research conducted in this field. Therefore, a detailed bibliometric analysis, including investigation of collaboration networks and citation patterns, should be conducted. The updated version of the Global Applications of Soil Erosion Modelling Tracker (GASEMT) database contains information about citation characteristics and publication type. Here, we investigated the impact of the number of authors, the publication type and the selected journal on the number of citations. Generalized boosted regression tree (BRT) modelling was used to evaluate the most relevant variables related to soil erosion modelling. Additionally, bibliometric networks were analysed and visualized. This study revealed that the selection of the soil erosion model has the largest impact on the number of publication citations, followed by the modelling scale and the publication's CiteScore. Some of the other GASEMT database attributes such as model calibration and validation have negligible influence on the number of citations according to the BRT model. Although it is true that studies that conduct calibration, on average, received around 30% more citations, than studies where calibration was not performed. Moreover, the bibliographic coupling and citation networks show a clear continental pattern, although the co-authorship network does not show the same characteristics. Therefore, soil erosion modellers should conduct even more comprehensive review of past studies and focus not just on the research conducted in the same country or continent. Moreover, when evaluating soil erosion models, an additional focus should be given to field measurements, model calibration, performance assessment and uncertainty of modelling results. The results of this study indicate that these GASEMT database attributes had smaller impact on the number of citations, according to the BRT model, than anticipated, which could suggest that these attributes should be given additional attention by the soil erosion modelling community. This study provides a kind of bibliographic benchmark for soil erosion modelling research papers as modellers can estimate the influence of their paper., Nejc Bezak and Matjaž Mikoš would like to acknowledge the support of the Slovenian Research Agency through grant P2-0180. Diana Vieira is funded by national funds (OE), through FCT – Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen - DL57/2016 (CDL-CTTRI-97-ARH/2018 - REF.191-97-ARH/2018), and acknowledges CESAM financial support of through (UIDP/50017/2020+UIDB/50017/2020). Jae E. Yang and Pasquale Borrelli are funded by the EcoSSSoil Project, Korea Environmental Industry & Technology Institute (KEITI), Korea (Grant No. 2019002820004). Walter Chen is funded by the Ministry of Science and Technology (Taiwan) Research Project (Grant Number MOST 109-2121-M-027-001).

40 Pags.- 10 Figs.- 2 Tabls.- Suppl. Informat. The definitive version is available at: https://www.sciencedirect.com/science/journal/00489697, To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published between 1994 and 2017. We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named ‘Global Applications of Soil Erosion Modelling Tracker (GASEMT)’, includes 3030 individual modelling records from 126 countries, encompassing all continents (except Antarctica). Out of the 8471 articles identified as potentially relevant, we reviewed 1697 appropriate articles and systematically evaluated and transferred 42 relevant attributes into the database. This GASEMT database provides comprehensive insights into the state-of-the-art of soil- erosion models and model applications worldwide. This database intends to support the upcoming country-based United Nations global soil-erosion assessment in addition to helping to inform soil erosion research priorities by building a foundation for future targeted, in-depth analyses. GASEMT is an open-source database available to the entire user-community to develop research, rectify errors, and make future expansions., Jae E. Yang and Pasquale Borrelli are funded by the EcoSSSoil Project, Korea Environmental Industry & Technology Institute (KEITI), Korea (Grant No. 2019002820004). Diana Vieira is funded by national funds (OE), through FCT – Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen - DL57/2016 (CDL-CTTRI-97-ARH/2018 - REF.191-97-ARH/2018), and acknowledges CESAM financial support of through (UIDP/50017/2020+UIDB/50017/2020). Walter Chen is funded by the Ministry of Science and Technology (Taiwan) Research Project (Grant Number MOST 109-2121-M-027-001). Nejc Bezak and Matjaž Mikoš would like to acknowledge the support of the Slovenian Research Agency through grant P2-0180.

1 Pag. © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License., To assess the effects of extreme storms in rainfed agriculture catchments on soil organic carbon removal, surface soil samples from different land uses were collected in a medium-sized catchment at the foot of Santo Domingo range. The study area was mostly cultivated at the beginning of the 19th century but changed to rangeland and afforestation forest in the last 50 years. The remaining cropland area is mostly rainfed agriculture that leaves soils unprotected in periods when erosive storms occur (autumn convective rainfalls).

12 Pags.- 5 Tabls.- 5 Figs., Several decades of intensive rainfed farming in Mediterranean mountains and later land abandonment has led to rapid land use and land cover changes. During recent centuries, the conversion of rangelands into croplands has increased the surfaces prone to erosion. In the southern Pre-Pyrenees, the process was reversed during the middle of the twentieth century, allowing the recovery of vegetation and subsequent variation in land cover. This work aims to assess how land use changes after generalised land abandonment affect some major soil properties related to soil quality. For this purpose, 98 replicate bulk soil samples were collected in a 23 km2 catchment that was mostly cultivated at the beginning of the last century. Soil samples were distributed over areas representing the main land uses (agricultural land, natural forest, pine afforestation and scrubland). Bulk density, stoniness, grain size, pH, carbonates, electrical conductivity, soil organic carbon (SOC), total nitrogen (TN), water retention capacity and magnetic properties (low frequency magnetic susceptibility (LF) and frequency dependence (FD)) were analysed in the samples from different land use areas. A past scenario was recreated using estimated data from the SPEROS-C model in order to evaluate changes in SOC over time. Furthermore, a multitemporal analysis of the Normalised Difference Vegetation Index of Landsat images was performed between 1972 and the present in order to assess the dynamics of revegetation. After land abandonment, 16.5% of the area remained as croplands, but afforestation and natural revegetation occupied 83.5% of the catchment. The highest mean value for SOC was found in the pine afforested area and the highest TN mean value was found in the natural forest. The lowest mean values for SOC and TN were recorded on the agricultural land. These results show the impact of soil changes produced by land use changes in fragile Mediterranean mountain agroecosystems., This research was financially supported by the project TRAZESCAR (CGL2014-52986-R) with the aid of a predoctoral contract (BES-2015-071780) funded by the Spanish Ministry of Science, Innovation and Universities.

46 Pags.- 8 Figs.- 5 Tabls. The definitive version is available at: https://www.sciencedirect.com/science/journal/03418162, Fallout radionuclides, such as Caesium-137, were proven to be a valuable means for studying medium-term (c.a. 50 years) soil erosion processes. In order to gain knowledge on the spatial distribution of 137Cs in volcanic soils of Andean Patagonia, 137Cs reference inventories were established along a precipitation gradient. At the subhumid sector, patterns of 137Cs gain/loss associated with land use were also determined considering native forests under grazing, a degraded rangeland and a pine plantation. Along the rising rainfall gradient (750–1400 mm), pedogenesis of volcanic ash soils, non-crystalline mineral formation, organic matter content and soil porosity varied, increasing in moister areas. Radionuclide inventories varied along the edaphoclimatic gradient, reaching mean values of 192, 267 and 576 Bq m−2, at study areas with 750, 950 and 1400 mm of annual precipitation, respectively. The 137Cs inventory followed an exponential relationship with precipitation, which could be related to the presence of allophane as the colloidal material in the soils from the rainiest area. The penetration depth reached by 137Cs varied between 15 and 25 cm, according to rain amount and soil texture. Most of the 137Cs fallout was retained in the uppermost 10 cm of the profiles and an exponential decline of 137Cs with depth, highly related to organic matter contents, was found. At the subhumid study area, both 137Cs mass activity and inventory, significantly decreased under the different land uses, with respect to reference soils. Although the pattern of 137Cs gain/loss varied according to topography, soil properties (organic matter and porosity) and vegetation cover, showing eroding and aggrading profiles, most samples had 137Cs values lower than the reference value, suggesting loss of soil as a consequence of erosion processes. Furthermore, as much as 45%, 58% and 70% of sample points from native forests, plantation and rangeland, respectively, had 137Cs values below the limit of detection. In the study transects, the loss of the upper 15 cm of soil in the subhumid sector during the last 50 years, highly exceeding tolerable erosion rates, highlights the urgent need for applying effective soil conservation measures. Reference inventories, which vary according to the edaphoclimatic gradient, and the loss of the radionuclide in sites with anthropic intervention, show the potential for using 137Cs measurements for assessing erosion processes in the Patagonian Andean Region., This research was funded by PICT-FONCyT 1715/10, CGL2014-52986-R and a Fellowship from Carolina Foundation. We aknowledge M. Calderón for his help with topographic fieldwork.

1 .pdf copy (1 Pag.) of the abstract published by the Organization. © Author(s) 2019. CC Attribution 4.0 license., As in other regions of the world, glaciers in South America like in Torres del Paine National Park are shrinking. The trends of increasing temperatures would accelerate melting process that will affect not only populations but also natural resources as water and soil that support life. Recent works in other polar and cold regions have shown the usefulness of combining fallout radionuclides and soil organic carbon (SOC) for tracking recent glacier retreat on glacial formations of proglacial environments.

3. pdf files, with 1) Text (11Pags.); 2) Tabls. (5); 3) Figs. (4). The definitive version is available at: https://www.sciencedirect.com/science/journal/03783774, The aim of this research was to analyse the effect of rainfall intensity and slope on soil and nutrient losses by hydric erosion in soils with different hydrological characteristics. This research was carried out on soils collected from slopes with different land uses/covers (LU/LC) -forest, scrub, agricultural, afforested and barren land-, from a mountain area (Sierra de Santo Domingo in the South Pyrenean region), where intensive farming and land use changes including land abandonment and changes in soil cover have occurred. Soils were placed on erosion boxes (30 cm × 20 cm) and compacted to a bulk density similar to that measured in the field (slope values ranged between 10 and 20%). Soil properties such as organic matter content, soil texture and N and P contents were analysed (values used as concentration in the original soil). Soils were subjected to simulated rainfall with intensity values usually recorded in the area during storms. Runoff volumes were collected at 10 min intervals from the time that runoff was generated. The steady infiltration rate as well as the average runoff rates and soil losses were evaluated for each land use. In the runoff samples, sediment concentration and nutrients (N and P) were analysed using different aliquots. The comparative analysis of the results obtained under simulated rainfall in plots with soils from different land uses allowed determining the differences in contribution of each land use to soil and nutrient losses when they are subjected to similar rainfall intensities. The results showed that the maximum runoff rates were reached in agricultural soil and barren land after 40 min at low intensity and after about 20 min at high intensity. However, in soils under forest, scrub and afforestation, runoff rates were much lower for the same rainfall intensity and duration period. Soil sealing was the main factor reducing infiltration in the agricultural and in barren LU/LC soils, while in the other cases runoff was mainly produced after saturation. Soil losses were more than 10xtimes higher in barren land and in agricultural soils than in the other land uses. Nitrogen losses in agricultural soils were about 3 times higher than in forest, and scrub or in afforested LU/LC. Under high intensity rainfall, there was an enrichment ratio (ER) of nitrogen in the sediment in relation to the original soil, which was higher in scrub and agricultural lands (up to 1.33 and 1.32, respectively) than in the rest of land uses (1.1 on average). Phosphorous losses were mainly associated with soil particles and the land uses that gave rise to higher P losses was agricultural under any intensity, while P losses increased significantly in forest and afforested LU/LC at high intensity. The enrichment ratio (ER) was higher in agricultural soils (up to 1.82, increasing with intensity), forest and afforested LU/LC (1.33 and 1.16, respectively under high intensity) than in scrub (1.22) and barren lands (near 1). Information gained in this research can be of interest to manage mountain agroecosystems to limit N and P supply from headwaters to hydrological systems., This research is part of the project CGL2014-52986-R which was funded by the Spanish Ministry of Economy and Competitiveness.

11 Pags.- 2 Tabls.- 8 Figs., In Mediterranean mountain agroecosystems, soil erosion associated with the development of ephemeral gullies is a common environmental problem that contributes to a loss of nutrient‐rich topsoil. Little is known about the influence of ephemeral gully erosion on particle size distribution and its effect on soil organic (SOC) and inorganic (SIC) carbon among different sized soil particles in agricultural soils. In this study, laboratory tests were conducted using velocity settling tube experiments to examine the effects of erosion on sediment particle size distributions from an incised ephemeral gully, associated with an extreme event (235 mm). We also consider subsequent deposition on an alluvial fan in order to assess the distribution of SOC and SIC concentrations and dissolved carbon before and after the extreme event. Soil fractionation was carried out on topsoil samples (5 cm) collected along an ephemeral gully in a cultivated field, located in the lower part of a Mediterranean mountain catchment. The results of this study showed that the sediment transported downstream by runoff plays a key role in the particle size distribution and transportability of soil particles and associated carbon distribution in carbonate rich soils. The eroding sediment is enriched in clay and silt‐sized particles at upslope positions with higher SOC contents and gradually becomes coarser and enriched in SIC at the end of the ephemeral gully because the finest particles are washed‐out of the study field. The extreme event was associated with an accumulation of dissolved organic carbon at the distal part of the depositional fan. Assessment of soil particle distribution using settling velocity experiments provides basic information for a better understanding of soil carbon dynamics in carbonate rich soils. Processes of soil and carbon transport and relationships between soil properties, erodibility and aggregate stability can be helpful in the development of more accurate soil erosion models., This work was funded by the CICYT project(CGL2014-52986-R).

42 Pags.- 4 Tabls.- 6 Figs. The definitive version is available at: https://www.sciencedirect.com/science/journal/01671987, In this study, the potential effect of the selective transport and deposition by interrill erosion on the spatial distribution of eroded soil and associated soil organic (SOC) and inorganic carbon (SIC) in carbonate-rich soils was investigated in Mediterranean cultivated Calcisols. Particular attention was paid to the role of calcium carbonate in the stabilization of SOC and its impact on soil structure and the settling behavior of soil particles in suspension. The settling velocity is a key variable in controlling the transport and fate of eroded sediment and sediment-associated carbon, which accounts for soil particle / aggregate size and density. The objectives were to analyze the settling behavior of cultivated soils at two contrasting slope positions, representative of erosion and deposition sites, in an interrill area and compare with those of uncultivated and undisturbed soils (not affected by deposition or erosion processes). Besides we examined the distribution of SOC and SIC associated with different particle size classes. Soils were fractionated into five size classes (>250, 125–250, 63–125, 32–63 and ≤32 μm) using a settling tube procedure and carbon contents (SOC and SIC, %) were measured at each settling size classes. The results indicated that the particle size selectivity of interrill erosion affects the distribution of soil particles and associated SOC and SIC spatial variability. As a result of erosion processes, cultivated soil at the upper part of the slope was enriched in finer fractions compared to the lower part where mainly coarse particles were deposited and the finer material was transported and washed out. Cultivation leads to a depletion of SOC and of the >250 μm fraction in comparison with uncultivated and undisturbed soil, where the SOC content was two times higher than in cultivated soil. Lighter and smaller settling size classes (≤63 μm) had the highest SOC content in uncultivated and cultivated downslope soils. This is contrary to what occurs with SIC that acts as a cementing agent and promotes aggregation formation affecting soil structure. Therefore, sand-sized and silt-sized carbonates were accumulated in coarser size fractions in these soils, mainly in downslope positions. This study provides a first insight into the role of selective processes by interrill erosion and their impact on soil organic/inorganic carbon distribution affected by different particle selective transport process, soil aggregate size distribution and associated carbon in Mediterranean agroecosystems., This work was funded by the CICYT project (CGL2014-52986-R).

41 Pags.- 7 Figs.- 3 Tabls. The definitive version is available at: https://www.sciencedirect.com/science/journal/03014797, In the Mediterranean region, floods are expected to increase as a result of climate change and knowledge of soil erosion hot spots during exceptional rainfalls is required to support mitigation measures. This study quantifies the main sediment sources during an exceptional rainfall event in 2012 (235 mm) at the outlet of two catchments located in NE Spain. To this purpose, suspended sediments were collected during the flood event, complemented with entrapped sediments in mat taken one year after the event. We used fingerprinting methodology and applied the FingerPro unmixing model to estimate the contribution from main sources. The selected tracers clearly distinguished agricultural, rangeland, subsoil and channel banks as the four potential sources in both catchments. In the Vandunchil catchment, the 8 time-integrated suspended sediment samples revealed changes in source contribution during the 2-h sampling sequence. There were relatively high contributions from rangeland, agriculture and subsoil at the beginning of the sampling, representing 30, 40 and 35% of the total source contributions, respectively. Our records captured the delivery of pulses of eroded surface soil transported by runoff with direct connectivity to the stream. The sequence was followed by a sharp increase in channel bank contribution (up to 90%) in comparison to the other sources, reflecting streambank erosion and landslide occurrence, which manifested during the flood. In contrast, in the La Reina catchment, agricultural soils contributed the most (65%) and, together with subsoils (32%), were the main sources. These results reflect the effect of the higher connectivity and slope gradient of these cultivated fields of the La Reina catchment in comparison with those of the Vandunchil catchment. We discuss the possibility of using different properties, such as radionuclides, geochemistry and magnetic measurements, as tracers to distinguish between potential sources during an exceptional event in upland Mediterranean catchments. Our results support the use of fingerprinting techniques to determine variations in source contribution and sediment provenance during flood events, as extreme rainfalls are main drivers of sediment mobilization and key factors in changing landscapes. This is essential in identifying vulnerable hot spots, in which early-stage interventions are needed, and for helping policy makers with management of soil and water resources., This research was funded by the project (CGL 2014-52986-R)

11 Pags.- 4 Tabls.- 8 Figs., The present dominant trend of retreating and shrinking glaciers is leading to the formation of new soil in proglacial zones. The Cordillera Blanca located in the Peruvian Andes includes the Lake Parón catchment known for the Artesonraju Glacier and its rapid retreat, forming the largest proglacial lake in the region. This work aims to gain knowledge of soil and vegetation development on the most representative proglacial landforms existing in the Parón catchment. Previous research in proglacial environments suggests that soil properties might indicate different ages of ice retreat besides the normalised difference vegetation index (NDVI), which is known to be a powerful tool for assessing vegetation development. In the area surrounding Lake Parón up to the glacier tongue, an altitudinal transect (4200–4700 m a.s.l.) was established for sampling topsoils. A total of 40 surface soil samples (0–3 cm) were collected from the main glacial landforms, moraines, colluvium, glacio-fluvial terraces and alluvial fans, developed after different stages of glacier retreat. Soil organic carbon (SOC) and SOC fractions (active and stable), total nitrogen (TN) and 137Cs were analysed. A multitemporal analysis of NDVI was performed to assess the vegetation dynamics in the Parón catchment and over the different glacial landforms over time (1987–2018). The NDVI increase in recent decades indicates an expansion of vegetation cover and density. We compared NDVI values with the SOC and TN content to assess the relationships with vegetation growth in mountain soils. NDVI and the distribution of SOC and TN content show a positive correlation between vegetation evolution and the enrichment in soil nutrients that are more abundant in older moraines in coincidence with highest NDVI. These results outline the effect of shrinking mountain glaciers on generating new soils in parallel with the growth of vegetation., This study was supported by the IAEA Technical Cooperation Programme through the INT/5/153 project “Assessing the Impact of Climate Change and its Effects on Soil and Water Resources in Polar and Mountainous Regions” and by the Spanish National Project CGL2014-52986-R.

38 Pags.- 5 Figs.- 3 Tabls. The definitive version is available at: https://www.sciencedirect.com/science/journal/03418162, Patterns of erosion, transport and deposition of soil particles not only affect the distribution of mineral fraction of the soil but their organic components. The spatial variability of soil nutrients in Mediterranean mountain agroecosystems that combine complex land uses and abrupt topography is poorly documented despite emerging concerns on nutrients fate require understanding the potential impact of soil erosion on nutrients redistribution across landscapes. This study aims to assess at catchment scale the spatial patterns of soil organic and inorganic carbon (SOC, SIC), soil organic carbon fractions and total nitrogen (TN) in relation to land uses and soil redistribution. To this purpose we selected a well characterized endorheic catchment located in NE Spain where soil erosion and deposition rates derived from 137Cs measurements were previously documented and we mapped the distribution of cropland and rangeland areas. A grid of 100 × 100 m was established for collecting a total of 205 soil samples for nutrients and standard soil analyses. In both rangeland and cropland the patterns of SOC and TN stocks were clearly related to 137Cs inventories thus significantly lower nutrient stocks (SOC: 34.1 ± 18.6 Mg ha−1, TN: 2.9 ± 1.7 Mg ha−1) were found in erosional sites whereas higher stocks (SOC: 44.9 ± 24.2 Mg ha−1, TN: 3.9 ± 2.3 Mg ha−1) were recorded in depositional areas. In cropland the mean nutrients contents (SOC: 1.1 ± 0.8%, TN: 0.1 ± 0.1%) were significantly lower than in rangeland (SOC: 3.2 ± 2.1%, TN: 0.2 ± 0.1%). The highest C/N ratios (29) were found in rangeland, while in cropland they occurred in depositional areas with their values below 10 in the erosional sites. In turn, the SIC content (range 0.4 to 10.2%) was slightly lower at the depositional sites (4.9 ± 2.2%) but not significantly different from the erosional sites (5.1 ± 2.2%). Cultivated and steep slopes led to loss of soil and nutrients due to intense erosion processes also related to tillage and crop productivity. Our findings provide evidence that the combined effect of land use and soil redistribution exert an important control on the spatial distribution of nutrients, highlighting a significant decrease of SOC and TN stocks with increasing soil erosion in croplands. The information gained achieves a better understanding of soil nutrients dynamics and further knowledge for effective land management of mountain agroecosystems in the Mediterranean region., This research was funded by the project (CGL2014-52986-R) of the Spanish Ministry of Science, Innovation and Universities.

17 Pags.- Figs.- Fots. Presentation into Workshop Block E, Wedsday 22.3.2017 Morning: Various (Coupling erosion with Soil organic carbon losses, Wind erosion modelling, Policies in soil conservation, rainfall erosivity, etc.). Creative Commons License Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).,  The main factor for soil redistribution is runoff through the gully system triggering the selective removal of finer soil particles mobilized the rich carbon fine fraction affects the depletion of soil particles and, therefore, SOC.  Settling velocity measurements provide direct information on soil aggregate distribution with implications on soil and SOC transportability that can be used in soil erosion modelling.  The combination of the spatially distributed SPEROS-C model combined with 137Cs measurements is a potential tool to evaluate erosion induced carbon fluxes.