Inventario y caracterización morfológica de lagos y lagunas de alta montaña en las provincias de Palencia y León (España)

High mountain lakes and lagoons are not a typical feature of the landscape of the Iberian Peninsula, but rather an exception in the natural environment, therefore its study and conservation presents great interest. This study arises in order to inventory and characterize a set of seventeen lagoon complex located over the provinces of Palencia and León, without any kind of size restriction. Likewise their basins are described, since they are related with them and they will determine their future evolution. Among other results, it should be noted that, despite they are situated at high altitude, they have a complex and varied hydrological network, denoting the high diversity of these systems. The lithology factor seems to affect significantly to the depth of the studied units, however depth and dimensions of the lakes are strongly related with the specific characteristics of their morphogenesis. In general, studied lakes and lagoons appear to be more fragile to possible alterations in their catchments if they are compared with bigger systems studied in the specialized literature.Los lagos y lagunas de alta montaña no son un rasgo típico del paisaje de la Península Ibérica, sino más bien una excepción en el medio natural, por ello su estudio y conservación presenta gran interés. Este trabajo surge con objeto de inventariar y caracterizar un conjunto de diecisiete complejos lagunares ubicados en las provincias de Palencia y León (Cordillera Cantábrica y Sierra de la Cabrera), sin ningún tipo de restricción por tamaño. Así mismo se describen sus cuencas, ligadas con las masas de agua y que determinarán su futura evolución. Entre otros resultados, cabe señalar que, a pesar de su carácter de cabecera, presentan una red hidrológica compleja y variada, denotando la diversidad de estos sistemas. La composición litológica parece incidir significativamente en la profundidad de las unidades, sin embargo la profundidad y dimensiones de las lagunas dependen en gran medida de las características concretas de su morfogénesis. En general, los lagos y lagunas estudiados parecen ser más frágiles ante posibles alteraciones en sus cuencas al compararlas con otros sistemas de mayor tamaño recogidos en diferentes estudios

Fish morphology and passage through velocity barriers. Experience with northern straight-mouth nase (Pseudochondrostoma duriense Coelho, 1985) in an open channel flume

Knowing the relationship between size, morphological traits and swimming performance of fish is essential to understand the swimming capacity to successfully surpass these obstacles and the selective pressure that barriers in rivers and streams could exert on fish. Northern straight-mouth nase, an endemic potamodromous cyprinid fish species from the Northwest of the Iberian Peninsula, was selected to carry out volitionally swimming performance experiments in an open channel against three different flow velocities, using telemetry and video cameras. The use of thin-plate spline, on 10 landmarks, evidenced unknown patterns linked to velocity barriers. At lower flow velocity, size is the main factor explaining the swimming performance; thus, large individuals swim up more efficiently. In contrast, at high flow velocities, shape becomes the essential explanatory variable; thereby, streamlined body shapes with a higher relative position of the tail and a narrower caudal peduncle are more efficient. The obtained results show the existence of a relationship between fish morphology and swimming performance, with potential consequences due to selection pressures associated with velocity barriers and their implications on behavioural and dispersal processes. To sum up, velocity barriers could exert a selection pressure on nase populations, so the fishway design and removal should be (re)considered

Capacidad de nado de ciprínidos potamódromos ibéricos: experimentación en el canal de nado de Vadocondes

The anthropogenic alteration in fluvial ecosystems is high, mainly due to the creation of transverse barriers (dams, weirs, gauging stations, drainage pipes, etc.), which modify their longitudinal connectivity, causing, among other impacts, the fragmentation of the habitat. This problem affects the migrating fish, because it can suppose a blockade or delay in their movements, reducing their habitats, threatening the viability and abundance of their populations, even reaching their extinction. The swimming capacity of the fish (swimming speed, fatigue time and distance traveled) is one of the factors that determine their survival. A system that allows to establish it, in natural conditions, are the voluntary open channel flume. In the flume of Vadocondes (Burgos) the swimming capacity has been determined, and how environmental and biometric factors influence in the swimming capacity, of two of the main species of cyprinids potamodromous of the Iberian Peninsula (Iberian barbel –Luciobarbus bocagei– and northern straight-mouth nase –Pseudochondrostoma duriense–, with the aim of being able to develop adequate technical and scientific guidelines, which guarantee an optimal and effective design of the fishways, which has a positive impact on the conservation of their populations.El grado de alteración antropogénica en los ecosistemas fluviales es elevado, debido, fundamentalmente, a la creación de barreras transversales (presas, azudes, estaciones de aforo, caños de drenaje, etc.), que alteran su conectividad longitudinal, causando, entre otros impactos, la fragmentación del hábitat. Esta problemática afecta a los peces migradores, pues puede suponer un bloqueo o retraso en sus movimientos, reduciendo sus hábitats, amenazando la viabilidad y abundancia de sus poblaciones, llegando incluso a su extinción. La capacidad de nado de los peces (velocidad de nado, tiempo de fatiga y distancia recorrida) es uno de los factores que determina su supervivencia. Un sistema que permite establecerla en condiciones naturales son los canales de nado voluntario. En el canal de nado de Vadocondes (Burgos) se ha determinado la capacidad de nado y cómo influyen en ella factores ambientales y biométricos, de dos de las principales especies de ciprínidos potamódromos de la Península Ibérica (barbo ibérico –Luciobarbus bocagei– y boga del Duero –Pseudochondrostoma duriense–, con el objetivo de poder desarrollar unas directrices técnicas y científicas adecuadas, que garanticen un diseño óptimo y eficaz de los pasos para peces, que repercuta positivamente en la conservación de sus poblaciones