The episcopal complex of Eio-El Tolmo de Minateda (Hellín, Albacete, Spain). Architecture and spatial organization. 7th to 8th centuries AD

The episcopal complex of Eio, located in El Tolmo de Minateda, was built between the end of the 6th century and the beginning of the 7th century, possibly as a political decision taken by the ecclesiastical authority in the capital of the Visigothic kingdom (Toletum). With the comprehensive study of the whole complex presented below (construction cycles, furniture, decoration and location of spaces), we can interpret the function of each space in the basilica and the domus episcopi, the liturgical and general movement routes, the existence of some hierarchical environments, and specify the chronological development of the buildings. After the Arab-Berber conquest of Hispania in the early 8th century, the whole complex will experience a series of transformations that will convert the religious and monumental public area into a private, residential and industrial Islamic quarter.

Feedbacks between vegetation pattern and resource loss dramatically decrease ecosystem resilience and restoration potential in a simple dryland model

Conceptual frameworks of dryland degradation commonly include ecohydrological feedbacks between landscape spatial organization and resource loss, so that decreasing cover and size of vegetation patches result in higher water and soil losses, which lead to further vegetation loss. However, the impacts of these feedbacks on dryland dynamics in response to external stress have barely been tested. Using a spatially-explicit model, we represented feedbacks between vegetation pattern and landscape resource loss by establishing a negative dependence of plant establishment on the connectivity of runoff-source areas (e.g., bare soils). We assessed the impact of various feedback strengths on the response of dryland ecosystems to changing external conditions. In general, for a given external pressure, these connectivity-mediated feedbacks decrease vegetation cover at equilibrium, which indicates a decrease in ecosystem resistance. Along a gradient of gradual increase of environmental pressure (e.g., aridity), the connectivity-mediated feedbacks decrease the amount of pressure required to cause a critical shift to a degraded state (ecosystem resilience). If environmental conditions improve, these feedbacks increase the pressure release needed to achieve the ecosystem recovery (restoration potential). The impact of these feedbacks on dryland response to external stress is markedly non-linear, which relies on the non-linear negative relationship between bare-soil connectivity and vegetation cover. Modelling studies on dryland vegetation dynamics not accounting for the connectivity-mediated feedbacks studied here may overestimate the resistance, resilience and restoration potential of drylands in response to environmental and human pressures. Our results also suggest that changes in vegetation pattern and associated hydrological connectivity may be more informative early-warning indicators of dryland degradation than changes in vegetation cover.

Pervivencia o “supervivencia” de la tradición en el Guadarrama segoviano. Procesos y prácticas

El aprovechamiento ganadero es el factor dominante de la organización del espacio en el Guadarrama segoviano. Si bien, desde el decenio de 1950, la actividad pecuaria empieza a entrar en un declive prolongado, reduciéndose el número de explotaciones y la cuantía de cabezas de ganado. Un abandono de las prácticas pastoriles que se evidencia, igualmente, en la inexorable tendencia hacia la simplificación en el manejo de los animales y la utilización selectiva del suelo. Sucede, de este modo, la crisis del sistema tradicional y del modelo territorial en el que este se apoyaba, progresivamente sustituido por una organización geográfica de corte tradicional-degradado. Es, en definitiva, lo que se ha convenido en titular como la “supervivencia” de la tradición. Y cuyo correlato se encuentra en el prolongado proceso de despoblación acontecido desde entonces, como las sensibles mermas de población registradas, las perceptibles modificaciones habidas en el tamaño y número de asentamientos o el excesivo grado de envejecimiento terminan por demostrar. Una “supervivencia” completamente supeditada, de este modo, al agotamiento social.