Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 12 2 2008 10.5194/hess-12-523-2008 http://www.hydrol-earth-syst-sci.net/12/523/2008/ http://www.hydrol-earth-syst-sci.net/12/523/2008/hess-12-523-2008.html http://www.hydrol-earth-syst-sci.net/12/523/2008/hess-12-523-2008.pdf 523 535 2008-03-06 Identifying erosive periods by using RUSLE factors in mountain fields of the Central Spanish Pyrenees M. López-Vicente mvicente@eead.csic.es A. Navas J. Machín Department of Soil and Water, Aula Dei Experimental Station, CSIC, P.O. Box 202, 50080 Zaragoza, Spain The Mediterranean environment is characterized by strong temporal variations in rainfall volume and intensity, soil moisture and vegetation cover along the year. These factors play a key role on soil erosion. The aim of this work is to identify different erosive periods in function of the temporal changes in rainfall and runoff characteristics (erosivity, maximum intensity and number of erosive events), soil properties (soil erodibility in relation to freeze-thaw processes and soil moisture content) and current tillage practices in a set of agricultural fields in a mountainous area of the Central Pyrenees in NE Spain. To this purpose the rainfall and runoff erosivity (R), the soil erodibility (K) and the cover-management (C) factors of the empirical RUSLE soil loss model were used. The R, K and C factors were calculated at monthly scale. The first erosive period extends from July to October and presents the highest values of erosivity (87.8 MJ mm ha−1 h−1), maximum rainfall intensity (22.3 mm h−1) and monthly soil erosion (0.25 Mg ha−1 month−1) with the minimum values of duration of erosive storms, freeze-thaw cycles, soil moisture content and soil erodibility (0.007 Mg h MJ−1 mm−1). This period includes the harvesting and the plowing tillage practices. The second erosive period has a duration of two months, from May to June, and presents the lowest total and monthly soil losses (0.10 Mg ha−1 month−1) that correspond to the maximum protection of the soil by the crop-cover ($C$ factor = 0.05) due to the maximum stage of the growing season and intermediate values of rainfall and runoff erosivity, maximum rainfall intensity and soil erodibility. The third erosive period extends from November to April and has the minimum values of rainfall erosivity (17.5 MJ mm ha−1 h−1) and maximum rainfall intensity (6.0 mm h−1) with the highest number of freeze-thaw cycles, soil moisture content and soil erodibility (0.021 Mg h MJ−1 mm−1) that explain the high value of monthly soil loss (0.24 Mg ha−1 month−1). The interactions between the rainfall erosivity, soil erodibility, and cover-management factors explain the similar predicted soil losses for the first and the third erosive periods in spite of the strong temporal differences in the values of the three RUSLE factors. The estimated value of annual soil loss with the RUSLE model (3.34 Mg ha−1 yr−1) was lower than the measured value with 137Cs (5.38 Mg ha−1 yr−1) due to the low values of precipitation recorded during the studied period. To optimize agricultural practices and to promote sustainable strategies for the preservation of fragile Mediterranean agrosystems it is necessary to delay plowing till October, especially in dryland agriculture regions. Thus, the protective role of the crop residues will extend until September when the greatest rainfall occurs together with the highest runoff erosivity and soil losses. Alpert, P., Ben-Gai, T., Baharad, A., Benjamín, Y., Yekutieli, D., Colación, M., Diodato, L., Ramis, C., Homar, V., Romero, R., Michaelides, S., and Manes, A.: The paradoxical increase of Mediterranean extreme daily rainfall in spite of decrease in total values, Geophys. Res. Lett., 29(11), 1536, doi:10.1029/2001GL013554, 2002. Arnaez, J., Lasanta, T., Ruiz-Flaño, P., and Ortigosa, L.: Factors affecting runoff and erosion under simulated rainfall in Mediterranean vineyards, Soil Till. Res., 93, 324–334, 2007. Barnolas, A. and Pujalte, V.: La Cordillera Pirenaica, in: Geología de España, edited by: Vera, J. A., SGE-IGME, Madrid, 231–343, 2004. Bochet, E., Poesen, J., and Rubio, J. L.: Runoff and soil loss under individual plants of a semi-arid Mediterranean shrubland: influence of plant morphology and rainfall intensity, Earth Surf. Proc. Land., 31, 536–549, 2006. BOE, Boletín Oficial del Estado: REAL DECRETO 2352/2004, de 23 de diciembre, sobre la aplicación de la condicionalidad en relación con las ayudas directas en el marco de la política agrícola com\'un, No. 309, Madrid (Spain), 2004. Brown, L. C. and Foster, G. R.: Storm erosivity using idealized intensity distributions, T. ASAE, 30, 379–386, 1987. Bullock, M. S., Kemper, W. D., and Nelson, S. D.: Soil cohesion as affected by freezing, water content, time and tillage, Soil Sci. Soc. Am. J., 52, 770–776, 1988. Castro, G., Romero, P., Gómez, J. A., and Fereres, E.: Rainfall redistribution beneath an olive orchard, Agr. Water Manage., 86, 249–258, 2006. Cook, H. F., Valdes, G. S. B., and Lee, H. C.: Mulch effects on rainfall interception, soil physical characteristics and temperature under \textitZea mays L., Soil Till. Res., 91, 227–235, 2006. Cuadrat, J. M., Saz, M. A., Vicente-Serrano, S. M., and Gonzalez-Hidalgo, J. C.: Water resources and precipitation trends in Aragon, Int. J. Water Resour. D., 23(1), 107–123, 2007. De Santisteban, L. M., Casalí, J., and López, J. J.: Assessing soil erosion rates in cultivated areas of Navarre (Spain), Earth Surf. Proc. Land., 31, 487–506, 2006. Di Stefano, C., Ferro, V., and Porto, P.: Length Slope Factors for applying the Revised Universal Soil Loss Equation at Basin Scale in Southern Italy, J. Agr. Eng. Res., 75, 349–364, 2000. Diodato, N.: Estimating RUSLE's rainfall factor in the part of Italy with a Mediterranean rainfall regime, Hydrol. Earth Syst. Sci., 8, 103–107, 2004. Eberbach, P. and Pala, M.: Crop row spacing and its influence on the partitioning of evapotranspiration by winter-grown wheat in Northern Syria, Plant Soil, 268, 195–208, 2005. FAO-ISRIC: World Reference Base, Rome, 1998. Gómez, J. A. and Nearing, M. A.: Runoff and sediment losses from rough and smooth soil surfaces in a laboratory experiment, Catena, 59, 253–266, 2005. González-Hidalgo, J. C., De Luis, M., Raventós, J., and Sánchez, J. R.: Spatial distribution of seasonal rainfall trends in a western Mediterranean area, Int. J. Climatol., 21, 843–860, 2001. Govers, G., Van Oost, K., and Poesen, J.: Responses of a semi-arid landscape to human disturbance: A simulation study of the interaction between rock fragment cover, soil erosion and land use change, Geoderma, 133, 19–31, 2006. Guitian, F. and Carballas, T.: Técnicas de análisis de suelos, Ed. Pico Sacro, Santiago de Compostela, Spain, 288 pp, 1976. Gyssels, G., Poesen, J., Liu, G., Van Dessel, W., Knapen, A., and De Baets, S.: Effects of cereal roots on detachment rates of single- and double-drilled topsoils during concentrated flow, Eur. J. Soil Sci., 57, 381–391, 2006. Hussein, M. H., Kariem, T. H., and Othman, A. K.: Predicting soil erodibility in northern Iraq using natural runoff plot data, Soil Till. Res., 94, 220–228, 2007. Knapen, A., Poesen, J., and De Baets, S.: Seasonal variations in soil erosion resistance during concentrated flow for a loess-derived soil under two contrasting tillage practices, Soil Till. Res., 94, 425–440, 2007. Kuhnert, M., Güntner, A., Zabel, K., Chabrillat, S., Haubrock, S., Creutzfeld, B.: Separation of rill and interrill erosion by qualitative and quantitative measurements in the field, Geophys. Res. Abstr., 9, 08223, 2007. Kvǽrnø, S. H. and Øygardena, L.: The influence of freeze-thaw cycles and soil moisture on aggregate stability of three soils in Norway, Catena, 67(3), 175–182, 2006. Lecce, S. A., Pease, P. P., Gares, P. A., and Wang, J.: Seasonal controls on sediment delivery in a small coastal plain watershed, North Carolina, USA, Geomorphology, 73, 246–260, 2006. López-Vicente, M. and Navas, A.: Solving topography of Digital Elevation Model in karstic environments: a case study in the External Ranges of the Pyrenees, in: Geomorphology in regions of environmental contrasts, edited by: Gutiérrez, F., Gutiérrez, M., Desir, G., Guerrero, J., Lucha, P., Marín, C., and García-Ruiz, J. M., Zaragoza: Abstracts Volume of the Sixth International Conference on Geomorphology, 388, 2005. López-Vicente, M., Navas, A., and Machín, J.: Variaciones espaciales del factor de erodibilidad K (RUSLE) en una cuenca con dolinas de colapso en el Pirineo oscense, in: Geomorfología y territorio, edited by: Pérez Alberti, A. and López Bedoya, J., Actas de la IX Reunión Nacional de Geomorfología, Cursos e Congresos. Universidad de Santiago de Compostela. Servizo de publicacións e Intercambio Científico, Ed. IV Serie, 201–211, Santiago de Compostela, 2006a. López-Vicente, M., Navas, A., Machín, J., and Gaspar, L.: Modelización de la pérdida de suelo en una cuenca endorreica del Pirineo oscense, Cuadernos de Investigación Geográfica, 32, 29–42, 2006b. López-Vicente, M., Nelson, R., Stockle, C. O., Navas, A., and Machín, J.: Modelización de la capacidad de transporte distribuida en subcuencas endorreicas del Pirineo oscense, in: II Simposio Nacional Sobre Control de la Degradación de Suelos, edited by: Jiménez Ballesta, R. and Álvarez González, A. M., Comunicaciones, Madrid, Spain, 813–817, 2005. Loureiro, N. S. and Coutinho, M. A.: A new procedure to estimate the RUSLE \textitEI$_30$ index, based on monthly rainfall data and applied to the Algarve region, Portugal, J. Hydrol., 250, 12–18, 2001. Machín, J., Navas, A., Domenech, S., López-Vicente, M.: El río Arlanza en cabecera: Evolución reciente y tendencias en condiciones de cambio global, Cuadernos de Investigación Geográfica, 31, 77–95, 2005. Martínez-Casasnovas, J. A. and Sánchez-Bosch, I.: Impact assessment of changes in land use/conservation practices on soil erosion in the Penedès-Anoia vineyard region (NE Spain), Soil Till. Res., 57, 101–106, 2000. Mathys, N., Esteves, M., and Grésillon, J. M.: The seasonal cycle of deposition and scouring in the channel network as a key process for erosion response in badlands catchments, (Draix, Alpes-de-Haute-Provence, France), Geophys. Res. Abstr., 9, 08654, 2007. Meehl, G. A., Arblaster, J. M., and Tebaldi, C.: Understanding future patterns of increased precipitation intensity in climate model simulations, Geophys. Res. Lett., 32(18), L18719, doi:10.1029/2005GL023680, 2005. Morgan, R. P. C.: A simple approach to soil loss prediction: a revised Morgan-Morgan-Finney model, Catena, 44, 305–322, 2001. Nadal-Romero, E., Regüés, D., Martí-Bono, C., and Serrano-Muela, P.: Badland dynamics in the Central Pyrenees: temporal and spatial patterns of weathering processes, Earth Surf. Proc. Land., 32, 888–904, 2007. Navas, A., Machín, J., and Soto, J.: Assessing soil erosion in a Pyrenean mountain catchment using GIS and fallout 137Cs, Agr. Ecosyst. Environ., 105, 493–506, 2005. Ramos, M. C. and Porta, J.: Rainfall intensity and erosive potentiality in the NE Spain Mediterranean area: results on sustainability of vineyards, Il Nuovo Cimento, 17, 291–299, 1994. Rawls, W. J., Brakensiek, D. L., and Saxton, K. E.: Estimation of soil water properties, T. ASAE, 25, 1316–1320, 1982. Regüés, D. and Gallart, F.: Seasonal patterns of runoff and erosion responses to simulated rainfall in a badland area in Mediterranean mountain conditions (Vallcebre, Southeastern Pyrenees), Earth Surf. Proc. Land., 29, 755–767, 2004. Renard, K. G., Foster, G. R., Weesies, G. A., McCool, D. K., and Yoder, D. C.: Predicting Soil Erosion by Water: A Guide to Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE). Handbook #703, U.S. Department of Agriculture, Washington, D.C., 1997. Renschler, C. S., Mannaerts, C., and Diekkruger, B.: Evaluating spatial and temporal variability in soil erosion risk – rainfall erosivity and soil loss ratios in Andalusia, Spain, Catena, 34, 209–225, 1999. Riera, S., López-Sáez, J. A., and Julià, R.: Lake responses to historical land use changes in northern Spain: The contribution of non-pollen palynomorphs in a multiproxy study, Rev. Palaeobot. Palyno., 141, 127–137, 2006. Sánchez, J. L., Fernández, M. V., Fernández, J. T., Tuduri, E., and Ramis, C.: Analysis of mesoscale convective systems with hail precipitation, Atmos. Res., 67–68, 573–588, 2003. Tapiador, F. J., Sanchez, E., and Gaertner, M. A.: Regional changes in precipitation in Europe under an increased greenhouse emissions scenario, Geophys. Res. Lett., 34(6), L06701, doi:10.1029/2006GL029035, 2007. Tejada, M. and Gonzalez, J. L.: The relationships between erodibility and erosion in a soil treated with two organic amendments, Soil Till. Res., 91, 186–198, 2006. U.S. Department of Agriculture: Soil Conservation Service, National Soils Handb. No. 430, 1983. Usón, A. and Ramos, M. C.: An improved rainfall erosivity index obtained from experimental interrill soil losses in soils with a Mediterranean climate, Catena, 43, 293–305, 2001. Vicente-Serrano, S. M. and Beguería-Portugués, S.: Estimating extreme dry-spell risk in the middle Ebro valley (northeastern Spain): A comparative analysis of partial duration series with a general Pareto distribution and annual maxima series with a Gumbel distribution, Int. J. Climatol., 23, 1103–1118, 2003. Wei, W., Chen, L. D., Fu, B. J., Huang, Z. L., Wu, D. P., and Gui, L. D.: The effect of land uses and rainfall regimes on runoff and soil erosion in the semi-arid loess hilly area, China, J. Hydrol., 335(3–4), 247–258, 2007. Zhang, X. C.: Spatial sensitivity of predicted soil erosion and runoff to climate change at regional scales, J. Soil Water Conserv., 61(2), 58–64, 2006.