Engineering education on geosciences in a changing world

Engineering aims to work with what knowledge is available to achieve society's goals (Coyle, Murphy, and Grimson 2007). The current environmental challenges and the characteristics of the labour market mean that the effectiveness of Engineering activities in Geosciences must be increased through the development of technical knowledge and the inclusion of suitable training aimed at solving real cases (European Commission 2010). Human capital – understood as the talents, skills and capabilities of higher education graduates – is perceived as an essential element for sustainable economic growth and development in the globalised economy (Sianesi and Van Reenan 2003). We need, therefore, to rethink our approaches to curriculum, instruction and assessment in science education, particularly because of the rapid growth of the scientific knowledge, tools/technologies and theories that have originated over the last 50 years (Duschl and Grandy 2013)

Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin

Rainfall is the key factor to understand soil erosion processes, mechanisms, and rates. Most research was conducted to determine rainfall characteristics and their relationship with soil erosion (erosivity) but there is little information about how atmospheric patterns control soil losses, and this is important to enable sustainable environmental planning and risk prevention. We investigated the temporal and spatial variability of the relationships of rainfall, runoff, and sediment yield with atmospheric patterns (weather types, WTs) in the western Mediterranean basin. For this purpose, we analyzed a large database of rainfall events collected between 1985 and 2015 in 46 experimental plots and catchments with the aim to: (i) evaluate seasonal differences in the contribution of rainfall, runoff, and sediment yield produced by the WTs; and (ii) to analyze the seasonal efficiency of the different WTs (relation frequency and magnitude) related to rainfall, runoff, and sediment yield. The results indicate two different temporal patterns: the first weather type exhibits (during the cold period: autumn and winter) westerly flows that produce the highest rainfall, runoff, and sediment yield values throughout the territory; the second weather type exhibits easterly flows that predominate during the warm period (spring and summer) and it is located on the Mediterranean coast of the Iberian Peninsula. However, the cyclonic situations present high frequency throughout the whole year with a large influence extended around the western Mediterranean basin. Contrary, the anticyclonic situations, despite of its high frequency, do not contribute significantly to the total rainfall, runoff, and sediment (showing the lowest efficiency) because of atmospheric stability that currently characterize this atmospheric pattern. Our approach helps to better understand the relationship of WTs on the seasonal and spatial variability of rainfall, runoff and sediment yield with a regional scale based on the large dataset and number of soil erosion experimental stations.Spanish Government (Ministry of Economy and Competitiveness, MINECO) and FEDER Projects: CGL2014 52135-C3-3-R, ESP2017-89463-C3-3-R, CGL2014-59946-R, CGL2015-65569-R, CGL2015-64284-C2-2-R, CGL2015-64284-C2-1-R, CGL2016-78075-P, GL2008-02879/BTE, LEDDRA 243857, RECARE-FP7, CGL2017-83866-C3-1-R, and PCIN-2017-061/AEI. Dhais Peña-Angulo received a “Juan de la Cierva” postdoctoral contract (FJCI-2017-33652 Spanish Ministry of Economy and Competitiveness, MEC). Ana Lucia acknowledge the "Brigitte-Schlieben-Lange-Programm". The “Geoenvironmental Processes and Global Change” (E02_17R) was financed by the Aragón Government and the European Social Fund. José Andrés López-Tarazón acknowledges the Secretariat for Universities and Research of the Department of the Economy and Knowledge of the Autonomous Government of Catalonia for supporting the Consolidated Research Group 2014 SGR 645 (RIUS- Fluvial Dynamics Research Group). Artemi Cerdà thank the funding of the OCDE TAD/CRP JA00088807. José Martínez-Fernandez acknowledges the project Unidad de Excelencia CLU-2018-04 co-funded by FEDER and Castilla y León Government. Ane Zabaleta is supported by the Hydro-Environmental Processes consolidated research group (IT1029-16, Basque Government). This paper has the benefit of the Lab and Field Data Pool created within the framework of the COST action CONNECTEUR (ES1306)

Development and analysis of the Soil Water Infiltration Global database.

In this paper, we present and analyze a novel global database of soil infiltration measurements, the Soil Water Infiltration Global (SWIG) database. In total, 5023 infiltration curves were collected across all continents in the SWIG database. These data were either provided and quality checked by the scientists who performed the experiments or they were digitized from published articles. Data from 54 different countries were included in the database with major contributions from Iran, China, and the USA. In addition to its extensive geographical coverage, the collected infiltration curves cover research from 1976 to late 2017. Basic information on measurement location and method, soil properties, and land use was gathered along with the infiltration data, making the database valuable for the development of pedotransfer functions (PTFs) for estimating soil hydraulic properties, for the evaluation of infiltration measurement methods, and for developing and validating infiltration models. Soil textural information (clay, silt, and sand content) is available for 3842 out of 5023 infiltration measurements (~76%) covering nearly all soil USDA textural classes except for the sandy clay and silt classes. Information on land use is available for 76% of the experimental sites with agricultural land use as the dominant type (~40%). We are convinced that the SWIG database will allow for a better parameterization of the infiltration process in land surface models and for testing infiltration models. All collected data and related soil characteristics are provided online in *.xlsx and *.csv formats for reference, and we add a disclaimer that the database is for public domain use only and can be copied freely by referencing it. Supplementary data are available at https://doi.org/10.1594/PANGAEA.885492 (Rahmati et al., 2018). Data quality assessment is strongly advised prior to any use of this database. Finally, we would like to encourage scientists to extend and update the SWIG database by uploading new data to it

Modelling the rainfall-runoff relationships in a large catchment dominated by olive orchards in Southern Spain

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena del 7 al 12 de abril de 2013.Water balance models at the monthly scale are commonly used for planning purposes due to the relative simplicity of their parameterization and the more common availability of monthly versus daily data. The aim of this study was to evaluate the performance of three hydrological models: one multiple linear regression (MLR) model and two water balance models (one with daily and the other with monthly time step). Runoff, in both the monthly (named SIMPA) and daily (named CNWB) water balance models, was calculated based on the Curve Number approach. The evaluation was conducted on a large catchment of 308 km2, whose main land use is olive crops, using a daily rainfall-runoff dataset of nine years (1996-2005). Validation of the models was based on monthly runoff data; calibration and sensitivity analysis of the water balance models were based on monthly data and Monte Carlo simulation of the most important parameters: maximum infiltration to the aquifer; maximum water volume stored in the soil; coefficient of the threshold of soil water for the runoff generation; recharge coefficient of the aquifers in the case of SIMPA, and Curve Number and recharge coefficient of the aquifers for CNWB. SIMPA and CNWB performed better than the MLR model. SIMPA results were strongly dependent on the parameter soil water storage capacity, although showed the best adjustment to measured data according to the Nash-Sutcliffe Efficiency (equal to 0.78 and 0.66 for calibration and validation, respectively). Although CNWB performed similarly to SIMPA with the calibration dataset, its validation Nash-Sutcliffe Efficiency (0.42) was lower than that obtained with SIMPA (0.66). Inconsistent parameterization could be obtained in both SIMPA and CNWB when the aquifer recharge coefficient was included in the set of parameters to be calibrated. The advantage of CNWB against SIMPA is that soil storage capacity is physically meaningful in the former and dependent on rainfall distribution in the later. Finally, extreme values were responsible for most simulated-measured runoff deviations for the three models. Despite the good performance and conceptual advantages of SIMPA and CNWB, they should not be applied without previous analyses of available datasets.Peer Reviewe

Spatial and temporal variability of grass cover in two olive grove catchments on contrasting soil types

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena del 7 al 12 de abril de 2013.Mediterranean climate conditions -characterized by the concentration of the precipitation in the seasons of autumn and spring, the low temperatures in winter and extremely warm and dry summers- determine that ground cover by adventitious (or cover crop) vegetation shows significant seasonal and annual variability. In addition, its spatial variability associates also, partially, to water availability among the landscape. This is especially relevant in olive orchards, an agricultural system under high erosion risk in the region where the establishment of herbaceous cover has proved to improve soil protection reducing erosion risk, as well as the improvement of soil properties (Gómez et al., 2009). All these benefits are based on small scale studies where full ground cover by the cover crop is relatively easy to obtain. However, few information is available about the actual ground cover achieved at farm scale, although preliminary observations suggests that this might be extremely variable (Gómez and Giráldez, 2009). This study presents the preliminary results evaluating the spatial and temporal evolution of ground cover by adventitious vegetation (the preferred option by farmers to achieve a cover crop) in two commercial olive farms during 2 hydrological years (2011-2012). The study was conducted in two farms located in the province of Cordoba, Southern Spain. Both were olive orchards grown under deficit irrigation systems and present a gauge station where rainfall, runoff and sediment loads have been measured from the year 2005. The soil management in “La Conchuela” farm was based in the use of herbicide in the line of olive trees to keep the bare soil all year round, and the application of selective herbicide in the lane between the olive trees to promote the grown of graminaceae grasses . In addition, the grass is mechanically killed in June. In the another farm, “Arroyo Blanco”, the grass spontaneous cover is allowed until mid-spring in which is also mechanically killed by several tractor passes. Ground cover was evaluated by a field surveys (4 per year) in which the same areas were measured at an approximate density of 4 samples/ha. In each point, over a 0.25 m2 area ground cover was measured using photographs, then point measurements were interpolated using method of Inverse Distance Weighting methods, to generate continuous distribution maps. The spatial and temporal evolution of ground cover in both farms presented a notably different patterns in both farms. In “La Conchuela”, maximum values of cover can be reached in winter (61%, Dec-2011) while in “Arroyo Blanco”, the maximum values were observed during the spring (50% May-2011) and are dramatically lower in the seasons of summer and autumn. These differences are justified by the influence of the management, the precipitation regime and the soil qualities such as the depth. On the other hand, the large spatial variability of ground cover measurements in both catchments, with coefficients of variation between 41 and 167%, was mainly led by the topography. In both farms the highest values of ground cover were found in those areas with deeper soils located in also in converging areas where surface runoff is concentrated. In the highest and shallowest area, soil management operations might improve the establishment of the vegetation as well as to address the growing in the most erosive periods. Finally, the impact of grass cover on the hydrological and erosive responses in the catchment is also discussed.Peer Reviewe

Curve numbers for olive orchard catchments in Spain

Trabajo presentado en la EGU General Assembly 2014 (European Geosciences Union), celebrada en Viena del 27 de abril al 2 de mayo de 2014.The Curve Number (CN) method (Soil Conservation Service, 1972) is widely applied around the world to estimate direct runoff and the corresponding hydrograph of a rainfall event. Its efficient and simple computation, its complete parameterization for different soils, uses and managements and its good performance justify its application. Nevertheless, apart from Romero et al. (2007) who calculated CN-values at the plot scale, there is little information on the model performance in olive orchards at the catchment scale. In this work, the CN-model has been applied in three small catchments in Spain ranging between 6 and 8 ha with different soil types (regosol, luvisol and vertisol), topography (mean slopes between 9-15%) and management practices (non-tillage with a spontaneous grass cover, minimum tillage, conventional tillage). A rainfall-runoff dataset of 6 years have been used to test the usefulness of model as well as the accuracy of its reference parameterization (CNs and of initial substraction, Ia). CN-values were adjusted, optimized and compared with reference values for orchard crops while the sensitivity of the goodness of fit to Ia was described for each catchment. Classical equations based on the use of CN-percentiles 50, 10 and 90 for determining the antecedent mois- ture content (AMC) provided very good results with Nash-Sutcliffe coefficients of efficiency equal to 0.73 and 0.81 in two of the catchments with an annual rainfall higher than 600 mm. The third one -with an annual rainfall lower than 400 mm and spontaneous grass cover- showed a different pattern where a multiple linear regression dependant on precipitation and temperature features, represented notably better the rainfall-runoff relationships. Although fractions of Ia on the storage (S) equal to 0.15 and 0.25 allowed to optimize the adjustments of CN, the usual reference of 0.20 is quite appropriate. Finally, significant deviations were observed on reference-CNs for sandy soils that should be considered for hydrological calculations in olive orchard catchments.N

Development of a virtual tool for the quantication and the analysis of soil erosion in olive orchards based on RUSLE

Comunicación presentada en la European Geosciences Union General Assembly, celebrada en Viena del 7 al 12 de abril de 2013.Erosion rates above 30 t ha-1 yr-1 have been measured in hilly agricultural regions such as Andalusia in Southern Spain, associated to orchard crops (Gómez et al., 2008). In this region, there are 1.48 Mha of olive groves (CAP, 2007), which are essential in terms of income, employment and landscape. The acquisition of training and experience in modelling soil erosion is difficult by the conventional system teaching for students as well as specific technicians.Peer Reviewe

Vulnerability of olive orchards under the current CAP (Common Agricultural Policy) regulations on soil erosion: a study case in Southern Spain

To measure the erosive processes taking place under conditions close to those experienced by farmers and land managers; analyses on spatial units adapted to the size of the farm must be carried out; in a non-isolated way in the case of conventional plots. The objective of this study was to describe and understand the current state – in terms of high soil losses and degradation risk – of a commercial olive farm following the CAP agro-environmental requirements as well as the interaction between soil management decisions and rainfall variability. In this work, rainfall and runoff soil loss for 6.4 hydrological years (2005–2011) were monitored in the outlet of an olive orchard microcatchment of 6.7 ha. The equipment used was a flume with an ultrasonic sensor to measure flow height, a rainfall gauge and a sediment sampler. Management systems and olive yields were described for the study period. Different management operations (no-tillage, conventional tillage, no herbicides with tillage and mulch) were applied in the field as a result of the farmer adapting to yearly conditions and to recommendations on good agricultural practice. Our results indicate that the interaction between the factors of annual climatological features and management determined the hydrology, soil loss and olive yield. On the annual scale, cumulative rainfall and rainfall erosivity varied between 600 and 1000 mm and 600 and 1500 MJ Mm ha−1 h−1, respectively. The average annual runoff coefficient was equal to 15 ± 10%, while total sediment loss ranged from 20 t ha−1 year−1. Olive yield ranged between 5000 kg ha−1 year−1 and 10,000 kg ha−1 year−1. Above average annual rainfall values were associated with both high yields and soil losses >10 t ha−1 year−1. For the study period, frequent events with a low return period resulted in soil losses >10 t ha−1, despite the use of different soil management techniques and the compliance of CAP agro environmental regulations. The high risk of soil degradation evaluated might mean that the criterion based on slopes >10% is not suitable for the application of agro-environmental requirements of CAP. On the other hand, further research on conservation technologies such as a more efficient use of cover crops, mulches and plant barriers, controlled traffic farming and/or changes in land use is needed.This study was partly supported by Projects P08-AGR-03925 (Andalusian Government) and AGL2009-12936-C03-01 (Spanish Ministry of Science and Innovation), RESEL (Spanish Ministry for Agriculture, Feed and Environment) and by FEDER funds.Peer reviewe

Cost analysis of gully restoration in agricultural areas in Andalusia (Spain)

Póster presentado en la European Geosciences Union General Assembly, celebrada en Viena del 7 al 12 de abril de 2013.Cost optimization of soil conservation measures is essential in the agricultural sector where the farmers return of investment is usually small, and there is a high degree of uncertainty about yield. The main aims of this study are: 1) to assess the cost of check dams and revegetation measures for a wide range of situations on gully networks of Andalusia and 2) provide an estimation of the adequate budget requirements for the gully restoration at farms included in the public Incentive Program for Gully Control (IPGC) supported by the Junta de Andalucia (Spain). Firstly, a study was conducted to design the structures adapted to a wide variety of gully conditions (slope, width, height, unitary discharge) in the region of Andalusia, and check dam materials (concrete and gabions) taking into account conventional engineering stability criteria, recommendations in technical literature (Gómez et al., 2011) and principles of energy dissipation maximization (Castillo, 2012). In addition, the cost of the conservation measures was estimated by using current market prices of local resources (for interventions with farmers own means) and national construction prices list (if the works were hired to an external company). The cost of the interventions was expressed as a multivariate function of the gully characteristic by means of regression analysis to facilitate its use for budget estimation purposes. Finally, these equations were applied to the farms included in the IPGC database to provide an estimation of the adequate budget required for a successful implementation of this initiative, as well as to propose unitary indexes (i.e. cost per gully meter in the longitudinal profile or per square meter in plan view) that could serve as useful criteria for this, or future programs, to allocate resources to individual farms based on specific characteristics of the gully erosion problems they suffer.Peer Reviewe