Estudi i revalorització dels paisatges culturals de l'alta muntanya pirinenca: la vall del Madriu (Andorra), patrimoni de la humanitat de la UNESCO

Estudi arqueològic integrat de la vall del Madriu-Perafita-Claror (Andorra) iniciat al 2004 sota la coordinació de l’ICAC. L’estudi s’insereix en la declaració de la vall com a Patrimoni de la Humanitat (UNESCO). Las recerques s’enfoquen des de l’Arqueologia del Paisatge, de manera diacrònica i pluridisciplinar, fent especial atenció a les relacions de les societats amb el medi. Les restes arqueològiques treballades s’associen a activitats ramaderes, metal•lúrgiques i de carboneig. La recerca paleoecològica se centra en sediments lacustres, torbosos i arqueològics. L’any 2006, s’han analitzat a alta resolució temporal dues seqüencies palinològiques: l’estany Blau (2471 m) i la torbera de Bosc dels Estanyons (2180 m), obtenint les principals fases d’explotació i antropització d’aquest espai altimontà, així com l’evolució del paisatge en els darrers 11000 anys . La campanya de camp s’ha centrat en l’obtenció de mostres de pluja pol•línica referencial a la vall i en el sondatge de l’estany Forcat (2539 m). Un total de tres mostres han estat enviades a datar per C14. Els treballs arqueològics s’han centrat en l’excavació de sondejos de diagnòstic als jaciments de Basses de Setut (2325 m) i Pleta de les Bacives ( 2530 m) i en la realització de prospeccions a les capçaleres de les valls de Madriu, Perafita i Claror. S’han documentat estructures arqueològiques i s’han realitzat estudis antracològics dels sediments excavats en aquestes. S’ha realitzat un transecte altitudinal de carboneres al llarg de la vall per tal de enregistrar una major diversitat cronològica dels espais de carboneig. S’han enviat datacions C14 per tal de determinar la cronologia de les estructures. Les datacions del 2005 mostren una intensa ocupació ramadera i de carboneig a partir del segle XIV, en època baixmedieval i moderna, així com un establiment metal·lúrgic d’època romana.

Ecología del paisaje y sistemas de información geográfica ante el cambio socioambiental en las áreas de la montaña mediterránea. Una aproximación metodológica al caso de los valles d'Hortmoier y Sant Aniol

Este artículo es una aproximación a los métodos utilizados para analizar, cuantificar y valorar los cambios en los usos y cubiertas del suelo en estos dos valles que forman parte del espacio natural protegido de la Alta Garrotxa. La dinámica vivida en este territorio es un claro ejemplo de los procesos acaecidos a lo largo del siglo XX en buena parte de las áreas de montaña mediterránea. Una dinámica caracterizada fundamentalmentepor un incremento de la superficie forestal en detrimento del espacio agrario. Así mismo se proponen pautas metodológicas para su adecuada cartografía, así como para determinar las áreas potencialmente recuperables de espacio agrario con el objetivo de mantener la diversidad paisajística, biológica y el patrimonio cultural con la ayuda de los SIG y la Ecología del Paisaje

Infraestructuras y desarrollo económico en el Pirineo Central (1850-2000)

This paper is aimed at describing the impact of infrastructure on the economic evolution of Central Pyrenees (i.e., Huesca and the Catalan"Alt Pirineu"). The text analyses if investment in railways, roads and dams favoured economic development or, on the contrary, was just an instrument to extract domestic resources. The paper distinguishes among three different periods. Firstly, during the second half of the nineteenth century and the first few years of the twentieth century, the lack of railway connections prevented the economic development of the area. Secondly, between the first decades of the twentieth century and 1975, a road network was set up that reinforced the economic decadence of the most depressed valleys, and the construction of large dams was a powerful factor of depopulation all over the region. Finally, from 1975 onwards, some trends may be observed towards the correction of the previous policies.

Un gegant del cel en perill d'extinció : socialització i divulgació de la reintroducció del voltor negre a Catalunya

La interacció de l’home amb les diferents espècies amb les quals cohabita ha creat casos com el del Voltor Negre (Aegypius monachus), l’au necròfaga més gran d’Europa, que actualment es troba en perill d’extinció. La utilització del territori per a ús antropogènic (ramaderia, xarxes elèctriques, zones urbanes,...) ha fet disminuir la població d’aquesta espècie. Així com la incursió, de manera indirecta, en aquestes poblacions degut a l’acció de l’home podem destacar-ne’n dos, el més rellevant és la intoxicació per verí, degut a l’ús il·legal d’aquestes substàncies per al control de depredadors fa que els tòxics vagin pujant per la piràmide tròfica. La segona causa rellevant és la disminució d’aliment degut a la mixomatosis i a la normativa existent d’obligatorietat de retirada dels animals morts a muntanya per sota dels 1400m. Al fer l’anàlisi de problemàtiques, s’observa que la gran majoria són antròpiques, degudes a la desinformació i al desconeixement, per tant; per a realitzar un bon pla de reintroducció és necessari fer un treball previ de socialització de les poblacions de la zona per a que el projecte sigui eficient. El projecte consisteix en fer una conscienciació social als diferents grups implicats (turisme, escoles i població; ramaders i caçadors), mitjançant documents gràfics, material educatiu, material de suport i materials i mètodes de divulgació. Per a que la vall d’Alinyà i Boumort passin a ser destacades per la presencia establerta de les quatre aus necròfagues més rellevants d’Europa; l’Aufrany, el Trencalòs, el voltor comú i el nostre protagonista: el Voltor Negre.

Effects of coastal submarine canyons on tsunami propagation and impact

We analyse the variations produced on tsunami propagation and impact over a straight coastline because of the presence of a submarine canyon incised in the continental margin. For ease of calculation we assume that the shoreline and the shelf edge are parallel and that the incident wave approaches them normally. A total of 512 synthetic scenarios have been computed by combining the bathymetry of a continental margin incised by a parameterised single canyon and the incident tsunami waves. The margin bathymetry, the canyon and the tsunami waves have been generated using mathematical functions (e.g. Gaussian). Canyon parameters analysed are: (i) incision length into the continental shelf, which for a constant shelf width relates directly to the distance from the canyon head to the coast, (ii) canyon width, and (iii) canyon orientation with respect to the shoreline. Tsunami wave parameters considered are period and sign. The COMCOT tsunami model from Cornell University was applied to propagate the waves across the synthetic bathymetric surfaces. Five simulations of tsunami propagation over a non-canyoned margin were also performed for reference. The analysis of the results reveals a strong variation of tsunami arrival times and amplitudes reaching the coastline when a tsunami wave travels over a submarine canyon, with changing maximum height location and alongshore extension. In general, the presence of a submarine canyon lowers the arrival time to the shoreline but prevents wave build-up just over the canyon axis. This leads to a decrease in tsunami amplitude at the coastal stretch located just shoreward of the canyon head, which results in a lower run-up in comparison with a non-canyoned margin. Contrarily, an increased wave build-up occurs on both sides of the canyon head, generating two coastal stretches with an enhanced run-up. These aggravated or reduced tsunami effects are modified with (i) proximity of the canyon tip to the coast, amplifying the wave height, (ii) canyon width, enlarging the areas with lower and higher maximum height wave along the coastline, and (iii) canyon obliquity with respect to the shoreline and shelf edge, increasing wave height shoreward of the leeward flank of the canyon. Moreover, the presence of a submarine canyon near the coast produces a variation of wave energy along the shore, eventually resulting in edge waves shoreward of the canyon head. Edge waves subsequently spread out alongshore reaching significant amplitudes especially when coupling with tsunami secondary waves occurs. Model results have been groundtruthed using the actual bathymetry of Blanes Canyon area in the North Catalan margin. This paper underlines the effects of the presence, morphology and orientation of submarine canyons as a determining factor on tsunami propagation and impact, which could prevail over other effects deriving from coastal configuration.

Estudio de alta resolución de las fallas activas y procesos sedimentarios asociados al Cañón de São Vicente, margen Sudoeste de Iberia

The Southwest Iberian Margin is caracterized by an intense and diffuse seismic activity due to the convergence between Eurasian and African plates...

Arqueología de paisajes altimontanos pirenaicos: formas de explotación y usos del medio en época romana en valle del Madriu-Perafita-Claror (Andorra) y en la Sierra del Cadí (Alt Urgell)

long-term cultural history of the Madriu-Perafita-Claror valleys (Andorra) and the Cadí Range (Catalonia) has been investigated thanks to the combination of archaeological surveys and excavation, analysis of written sources, multiproxy alaeoenvironment analysis (pollen, NPP, micro and macro charcoal, sedimentology and geochemistry), and digital technologies such as stereophotogrammetry, multispectral imaging, DGPS and GIS. The project has been designed from a landscape archaeology approach and the study area has been selected due to the suitable setting it provides for a meaningful application of the aforementioned techniques. Consequently, archaeological, historical and palaeoenvironmental data have been all treated as cultural proxies. Their comparison has allowed obtaining not only coherent but also complementary results. The project outcomes show an uninterrupted occupation of these high mountain valleys (2000-2600 m a.s.l.) from the Mesolithic until the present. This human occupation shows strong spatial and chronological variability in human practices ranging from a stable long term group occupation in the Late Neolithic to the diversification of representative practices during the Roman period (metallurgy, pine resin exploitation, charcoal production, pastoralism, etc.). This high diversity of activities leads to complex cultural landscapes in the high Pyrenean areas. The reconstruction of the cultural history at the study areas will allow the development of more sustainable politics for these landscapes management.

Sedimentology and Stratigraphy of the Pleistocene sediments in Lake Llauset (Southern Pyrenees, Spain)-a first approach

The high alpine valleys in the Southem Pyrenees are characterised by a many small lakes and ponds. They occur above 2000 m and are said to have been formed by glacial erosion. The sediments in these basins should, therefore, contain s t p tigraphic information since deglaciation, at least. An interesting and may be one of the most important of these basins is Lake Llauset in the Alta Ribagorca. The Llauset basin has recently been developped for hydsopower production. In conection with the construction of the retaining wall at the 'Riegel' the sedimentary filling of the lake basin could be investigated, and the first sedimentological and stratigraphicalresults are presented.

Quaternary Glacial Geology of Alta Ribagorqa Basin (Central Southern Pyrenees)

This paper is an abstract of the doctoral thesis presented by the autor at the University of Barcelona on September 1983. It constitutes a regional study about the Quatemary Glacial Geology in the Ribagorca high valleys. It is the first work in relation to the geomorphology, sedimentology and stratigraphy of the glacial and related deposits in this zone of the Pyrenees. Several formations of quatemary deposits have been studied in detail (mainly in Llauset Valley and in Tall area); and the local quatemary stratigraphy is established and finally a correlation with some previously studied areas in the Pyrenees is attemped.

The Role of Canyons in Strata Formation

This paper provides a spatial and temporal multi-scale approach of European submarine canyons. We fi rst present the long-term geologic view of European margins as related to controls on submarine canyon development. Then we discuss the extent to which submarine canyon systems resemble river systems because both essentially form drainage networks. Finally, we deal with the hortest-term, highestresolution scale to get a fl avor of the current functioning and health of modern submarine canyons in the northwestern Mediterranean Sea. Submarine canyons are unique features of the seafl oor whose existence was known by European fi shermen centuries ago, especially for those canyons that have their heads at short distance from shoreline. Popular names given to specifi c canyons in the different languages spoken in European coastal communities refer to the concepts of a"deep" or"trench." In the old times it was also common thinking that submarine canyons where so deep that nobody could measure their depth or even that they had no bottom. Submarine canyons are just one of the seven different types of seafl oor valleys identifi ed by Shepard (1973) in his pioneering morphogenetic classifi cation. Shepard (1973) defined submarine canyons as"steep-walled, sinuous valleys, with V-shaped cross sections, and relief comparable even to the largest of land canyons; tributaries are found in most of the canyons and rock outcrops abound on their walls." Canyons are features typical of continental slopes with their upper reaches and heads cut into the continental shelf.

Estudio de alta resolución de las fallas activas y procesos sedimentarios asociados al Cañón de São Vicente, margen Sudoeste de Iberia

The Southwest Iberian Margin is caracterized by an intense and diffuse seismic activity due to the convergence between Eurasian and African plates...