Estimate of the (R)USLE rainfall erosivity factor from monthly precipitation data in mainland Spain

The need for continuous recording rain gauges makes it difficult to determine the rainfall erosivity factor (R-factor) of the (R)USLE model in areas without good temporal data coverage. In mainland Spain, the Nature Conservation Institute (ICONA) determined the R-factor at few selected pluviographs, so simple estimates of the R-factor are definitely of great interest. The objectives of this study were: (1) to identify a readily available estimate of the R-factor for mainland Spain; (2) to discuss the applicability of a single (global) estimate based on analysis of regional results; (3) to evaluate the effect of record length on estimate precision and accuracy; and (4) to validate an available regression model developed by ICONA. Four estimators based on monthly precipitation were computed at 74 rainfall stations throughout mainland Spain. The regression analysis conducted at a global level clearly showed that modified Fournier index (MFI) ranked first among all assessed indexes. Applicability of this preliminary global model across mainland Spain was evaluated by analyzing regression results obtained at a regional level. It was found that three contiguous regions of eastern Spain (Catalonia, Valencian Community and Murcia) could have a different rainfall erosivity pattern, so a new regression analysis was conducted by dividing mainland Spain into two areas: Eastern Spain and plateau-lowland area. A comparative analysis concluded that the bi-areal regression model based on MFI for a 10-year record length provided a simple, precise and accurate estimate of the R-factor in mainland Spain. Finally, validation of the regression model proposed by ICONA showed that R-ICONA index overpredicted the R-factor by approximately 19%.

John Tzetzes and the pseudo-Aristotelian Peplos in middle-Byzantium. The testimony of the Matritenses 4562 and 4621

Tras mi reciente edición de los pseudo-aristotélicos Pepli Epitaphia, el presente trabajo se centra en los apochrypha a dichos epitafios que compuso Juan Tzetzes en el siglo xii, un conjunto de ocho dísticos elegíacos para los héroes que consideró meritorios de tal tarea, y para quienes no pudo encontrar un epitafio conservado en las fuentes manuscritas a las que tuvo acceso. Para lograr dicho propósito, también se investiga el grado de conocimiento y la transmisión de ese corpus epigramático en la literatura bizantina, además de considerar las lecciones y el sentido mismo de dos códices guardados en la Biblioteca Nacional de España (M y Md). En ellos, Constantino Láscaris copió, directamente a partir de Tzetzes, dos breves antologías de dichos componentes.