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19 páginas, 6 figuras, 2 tablas. Proceedings of the NATO Mediterranean Dialogue Workshop on Desertification in the Mediterranean Region. A Security Issue -- Part IV. Regional cooperation and information sharing. Valencia, Spain 2-5 December 2003 ; Fire is one of the most important determining factors in the evolution of Mediterranean ecosystems. Its effects on soil are plural and diverse, acting on structure, chemical and physical properties, biota etc. Among them, the induced variations on soil water dynamics are of key importance for the recovery of the entire ecosystem and in the soil response to erosion processes. Forest fires are also a factor, triggering the risk of desertification. The aim of this study is to assess the impact effect of different fire intensities on soil hydrology and on runoff generation. This work was developed in the Permanent Experimental Field Station of La Concordia with nine plots (4 x 20 m), installed in a calcareous hillside, representative of Mediterranean shrubland areas. Experimental fires, of two intensity levels were carried out. Three plots were burned reaching high fire intensity and other three plots were burned with moderate intensity and the remaining plots were left undisturbed as control. Soil water content, water retention capacity and pF curves were measured together with runoff generation dynamics, in the different plots. The intrinsic characteristics of each rain event occurred up until a year after the fires and runoff generated on them were monitored. The data obtained was compared with the state of the plots seven years after, during the 2000-2002 period. In this period 24 rain events with runoff generation occurred, with average rainfall intensities (I30) around 10mm h-1. Both fire treatments show significant differences with respect to the Control plots, which are reflected in a value of runoff production of 76.84% as an average, less than the burned plots. Between fire treatments, the plots burned with high intensity fire, show the highest values of runoff yield. However, infiltration rates do not give significant differences between fire treatments. In the same way, plots that suffer a high intensity fire show greater values (22.50 cm3 cm-3) on water retention capacity than the other treatments, giving significant differences with the Moderate intensity plots and Control ones. Differences on this parameter between plots burned with Moderate intensity and the Control ones were observed but they were not statistically significant. The obtained pF curves show the same tendencies, being the greatest water content retained at pF of 2 in the burned plots and in the Control ones at pF of 4.2. The effect of fire degrading the vegetation cover and by means of the temperature impact on soil, produce changes in its structural characteristics and porosity, affecting soil water distribution and the effective response on water erosion processes. ; This work has been supported by the European Union (QLRT-2000-00289), the Spanish Ministry of Science and Technology (CICYT) REN2001-1716, and the Generalitat Valenciana (Conselleria de Medio ambiente-2002X628). ; Peer reviewed

10 páginas, 7 figuras, 7 tablas. ; An experimental study based on the effects of fire on soil hydrology was developed at the Experimental Station of 'La Concordia' (Valencia, Spain). It is located on a calcareous hillside facing SSE and composed of nine erosion plots (4 x 20 m). In summer 2003, after eight years of soil and vegetation recovery from previous fires in 1995 (with three fire treatments: T1 high-intensity fire, T2 moderate intensity, and T3 not burnt), experimental fires of low intensity were again conducted on the plots already burnt, to study the effects of repeated fires on the soil water infiltration, soil water content and runoff. Infiltration rates and capacities were measured by the mini-disk infiltrometer method (MDI), assessing the effects of vegetation cover by comparing the under-canopy microenvironment (UC) and its absence on bare soil (BS), immediately before and after the fire experiments. Soil properties like water retention capacity (SWRC) and water content (SWC) were also determined for the different fire treatments (T1, T2 and T3) and microsites (UC and BS). Hydrological parameters, such as runoff and infiltration rate, were monitored at plot scale from July 2002 to July 2004. In the post-fire period, data displayed a 20% runoff increase and a decrease in infiltration (18%). Differences in the steady-state infiltration rate (SSI) and infiltration capacity (IC) were tested with the MDI on the different treatments (T1, T2 and T3), and between the UC and BS microsites of each treatment. After fire, the SSI of the UC soil declined from 16 mm h(-1) to 12 mm h(-1) on T1, and from 24 mm h(-1) to 19 mm h(-1) on T2. The IC was reduced by 2/3 in the T1 UC soil, and by half on T2 UC soil. On the BS of T1 and T2, the fire effect was minimal, and higher infiltration rates and capacities were reached. Therefore, the presence/absence of vegetation when burnt influenced the post-burnt infiltration patterns at soil microscale. On the T3, different rates and capacities were obtained depending on the microsites (UC and BS), with higher SSI (25 mm h(-1)) and IC (226 mm h(-1)) on BS than on UC (SSI of 18 mm h(-1) and IC of 136 mm h(-1)). The SWRC and SWC were recovered from 1995 to 2003 (prior to the fires). The 2003 fire promoted high variability on the SWC at pF 0.1, 2 and 2.5, and the SWRC on burnt soils were reduced. To summarize, the IC and SSI post-fire decreases were related to the lower infiltration rate at plot scale, the significant differences in the SWRC between burnt and control treatments, and the increase in the runoff yield (20%). According to the results, the MDI was a useful tool to characterize the soil infiltration on the vegetation patches of the Mediterranean maquia, and contrary to other studies, on the UC soil, the infiltration rate and IC, when soil was dry, were lower than that obtained on BS. Once the soil gets wet, similar values were found on both microenvironments. ; We thank the financial support from the Agreement Generalitat Valenciana - CSIC (2005020112) 'Impacto de los incendios forestales repetidos sobre los procesos de erosión hídrica del suelo y la recuperación de la cubierta vegetal. Seguimiento y evaluación en una estación permanente de campo', and the Ministerio de Educación y Ciencia of the Spanish Government project 'Procesos y balances hidrológicos y de sedimentos a diferentes escalas espaciales en ambientes mediterráneos: Efectos de la variabilidad climática y los cambios de uso del suelo' (PROBASE CGL2006-11619). ; Peer reviewed

7 páginas, 4 figuras, 3 tablas. ; Soil macroaggregation in relation to soil organic matter (SOM) and calcium carbonate(CaCO3) content was studied, before and after experimental fires of different intensities, in two environments (under canopy and on bare soil). In 1995, two experimental fire treatments, based on the addition of different biomass amounts, were applied on a set of nine plots at the Permanent Field Station of La Concordia (Valencia, Spain). Three plots were burned with high intensity fire (T1), three with moderate intensity (T2) and three plots were left unburned to be used as control treatment (T3). Soils under canopy were characterized by higher macroaggregate stability (SMS), SOM content and mean weight diameter of aggregates (MWD) than bare soils, which presented higher CaCO3 contents. After the fires, tendencies to increase were observed in the SOM and SMS of all burned soils, probably because of the incorporation of partially burned plant material. The trends of SMS and SOM in T1 burned soils were towards to decrease with the occurrence of the first erosive rainfalls. These trends continued until the end of the study. MWD of under canopy soils on T1 and of soils on T2 showed a decreasing trend immediately after fire treatments. Not significant differences between sampling periods were found for CaCO3 content, with the exception of under canopy soils on T1 which tended to increase, and showed higher values at the end of the studied period. The differences observed initially between under canopy and bare soil disappeared after one year of fire in T1, which suggests a major degradation of soils affected by this treatment. Significant changes of the studied properties were not observed in unburned soils during one year of research. In these soils, organic matter showed significant correlations with macroaggregate stability and mean weight diameter. However, significant statistical relationships were not observed between the Studied properties in burned soils, showing that fire impact probably affected other soil characteristics related to soil aggregation. ; We thank the financial support from the Agreement Generalitat Valenciana — CSIC (2005020112) "Impacto de los incendios forestalesrepetidos sobre los procesos de erosión hídrica del suelo y la recuperación de la cubierta vegetal. Seguimiento y evaluación en una estación permanente de campo", and the Ministerio de Educación y Ciencia of the Spanish Government project "Procesos y balances hidrológicos y de sedimentos a diferentes escalas espaciales en ambientes mediterráneos: Efectos de la variabilidad climática y los cambios de uso del suelo" (PROBASE CGL2006-11619). ; Peer reviewed

12 páginas, 6 figuras, 3 tablas. ; In the Mediterranean area, forest fires have become a first-order environmental problem. Increased fire frequency progressively reduces ecosystem recovery periods. The fire season, usually followed by torrential rains in autumn, intensifies erosion processes and increases desertification risk. In this work, the effect of repeated experimental fires on soil response to water erosion is studied in the Permanent Field Station of La Concordia, Valencia, Spain. In nine 80 m2 plots (20 m long x 4 m wide), all runoff and sediment produced were measured after each rainfall event. In 1995, two fire treatments with the addition of different biomass amounts were applied. Three plots were burned with high fire intensity, three with moderate intensity, and three were unburned to be used as a control. In 2003, the plots with the fire treatments were burned again with low fire intensities. During the eight-year interval between fires, plots remained undisturbed, allowing regeneration of the vegetation–soil system. Results obtained during the first five months after both fire experiments show the high vulnerability of the soil to erosion after a repeated fire. For the burned plots, runoff rates increased three times as much asore than those of 1995, and soil losses increased almost twice. The highest sediment yield (514 g m-2) was measured in 2003, in athe plots of the moderate burned with moderate fire intensity treatment in 1995, which had yielded only 231 g m-2 of sediment during the corresponding period in 1995. Runoff yield from the control plots did not show significant temporal changes, while soil losses decreased from 5 g m-2 in the first post-fire period to 0.7 g m-2 in the second one. ; We thank financial support from the EEC project "Eco-engineering and conservation of slopes for long term protection against landslides, storms and erosion" (QLRT-2000-00289), the Convenio Generalitat Valenciana - CSIC (02020024) and the Ministerio de Ciencia y Tecnología of the Spanish Government project (CYCIT REN2001-1716). ; Peer reviewed

8 páginas, 5 figuras, 3 tablas. ; The influence of vegetation cover on soil hydrological properties and its response to the impact of different fire intensities, in a Mediterranean forest environment, has been evaluated. The study was carried out in the Permanent Experimental Field Station of La Concordia (Lliria-Valencia, Spain), on a set of nine erosion plots (4 x 20 m(2)). The Station is located on a calcareous hillside S-SE oriented, with soils of Rendzic Leptosol type and supporting Mediterranean shrubland vegetation. All runoff generated and sediment produced in every rain event was collected from each plot. The set up includes a system of sensors for the continuous monitoring of climatic parameters (air temperature and humidity, rain volume, intensity, etc.). In June 1995, a set of experimental fires was carried out to the Station. Three of the plots were burned with high intensity fire, three with moderate intensity and the remaining were left unaltered. Soil water content and water retention capacity (WRC) were measured in the different plots and in two different vegetation covers: under canopy (UC) and in bare soil (BS). The pF curves were also obtained for each fire treatment. A year after the fires (June 1995-June 1996), great differences, reaching 77.15%, in runoff generation between fire treatments and the control plots were observed. No significant differences were detected on water retention capacity between soils UC and BS in the burned plots. However, these differences appeared in the control plots, giving UC and BS values of 13% and 18%, respectively. Plots corresponding to the high intensity fire treatment showed values of WRC significantly higher than those of the moderate intensity and of the control treatments. The pF curves show that the values of water volume, at the different pressure points studied, were slightly greater on UC soil. Values obtained for BS samples are higher in the fire treatments, showing significant differences in respect to the control plots at pF 1 and 2. These differences were also observed for UC soil, but in this case at pF 2, 2.5 and 4.2. ; This work has been supported by the European Union (QLRT-2000-00289), the Spanish Ministry of Science and Technology (CICYT) REN2001-1716 and Convenio (Agreement) Generalitat Valenciana – CSIC (02020024). ; Peer reviewed

6 páginas, 5 tablas. ; Atherosclerosis is characterized by excessive proliferation of neointimal leukocytes and vascular smooth muscle cells (VSMCs). In mice, the manipulation of cell cycle inhibitors such as CDKN1B (p27) and CDKN1A (p21) modifies the risk of developing atherosclerosis. In humans, CDKN1A, CDKN1B and CDKN1C (p57) are differentially expressed in normal versus atherosclerotic vessels. A DNA‑polymorphism within the CDKN1B promoter has been associated with myocardial infarction (MI). In the present study, we analyzed the effect of CDKN1A, CDKN1C and CDKN2A (p16) polymorphisms on MI‑risk. A total of 316 patients (all male, < 55 years) and 434 controls were genotyped, and the allele and genotype frequencies were compared between the two groups. Two CDKN1C polymorphisms, a promoter GT‑repeat and a variable number of repeats of the amino acid PAPA‑motif, were associated with MI. The presence of two alleles ≤ 11‑repeats (9/11, 10/11 and 11/11 genotypes) was significantly less frequent among patients (p < 0.001). This difference was also significant when analyzing the subpopulation of smokers (p = 0.004), suggesting a protective role for these low‑repeat genotypes (OR = 0.49, 95%CI = 0.32–0.73). The PAPA‑BB homozygotes were significantly less frequent in patients, but this could be attributed to a linkage disequilibrium between the 11‑repeats and B alleles. No significantly different frequencies between patients and controls for the four CDKN1A (‑1026A/G, ‑754G/C, ‑369G/C and Ser31Arg) and the three CDKN2A (‑523 G/A, +22 G/A and Ala148Thr) polymorphisms was found. In conclusion, we provide here genetic evidence for the association between DNA‑variants in the CDKN1C/p57 gene and the risk of atherosclerosis and MI. ; This work was supported by grants from the Spanish Fondo de Investigaciones Sanitarias-Fondos FEDER European Union (FIS-03/005), and Red de Investigación Renal-REDINREN (RD06/0016). I.R. is the recipient of a Ramón y Cajal Fellow. ; Peer reviewed

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).

Soil degradation by water is a serious environmental problem worldwide, with specific climatic factors being the major causes. We investigated the relationships between synoptic atmospheric patterns (i.e. weather types, WTs) and runoff, erosion and sediment yield throughout the Mediterranean basin by analyzing a large database of natural rainfall events at 68 research sites in 9 countries. Principal Component Analysis (PCA) was used to identify spatial relationships of the different WTs including three hydro-sedimentary variables: rainfall, runoff, and sediment yield (SY, used to refer to both soil erosion measured at plot scale and sediment yield registered at catchment scale). The results indicated 4 spatial classes of rainfall and runoff: (a) northern sites dependent on North (N) and North West (NW) flows; (b) eastern sites dependent on E and NE flows; (c) southern sites dependent on S and SE flows; and, finally, (d) western sites dependent on W and SW flows. Conversely, three spatial classes are identified for SY characterized by: (a) N and NE flows in northern sites (b) E flows in eastern sites, and (c) W and SW flows in western sites. Most of the rainfall, runoff and SY occurred during a small number of daily events, and just a few WTs accounted for large percentages of the total. Our results confirm that characterization by WT improves understanding of the general conditions under which runoff and SY occur, and provides useful information for understanding the spatial variability of runoff, and SY throughout the Mediterranean basin. The approach used here could be useful to aid of the design of regional water management and soil conservation measures. ; This research was supported by projects funded by the MINECO-FEDER: CGL2014-52135-C3-3-R, CGL2014-59946-R, CGL2015-65569-R, CGL2015-64284-C2-2-R, and PCIN-2017-061/AEI. When this manuscript was first submitted Estela Nadal-Romero and Damià Vericat received a "Ramón y Cajal" postdoctoral contract (RYC-2013-14371 and RYC‐2010‐06264, Spanish Ministry of Economy and Competitiveness, MEC). Damià Vericat is now a Serra Húnter Fellow at the University of Lleida. María Fernández-Raga received a "José Castillejo" postdoctoral grant (Spanish Ministry of Education, Culture and Sports). Carla Ferreira was supported by a post-doctoral research grant from the Portuguese Science and Technology Foundation (SFRH/BPD/120093/2016). Mariano Moreno-de las Heras received a Juan de la Cierva postdoctoral contract (IJCI-2015-26463) from the MEC. José Andrés López-Tarazón received a Vicenç Mut postdoctoral fellowship from the Autonomous Balearic Government (CAIB PD/038/2016). José Andrés López-Tarazón and Ramon Batalla also acknowledge 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), and the CERCA Programme. This paper has benefited from the Lab and Field Data Pool created within the framework of the COST action CONNECTEUR (ES1306).

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).