Francisco Carreño

Impacts of changes in land use and fragmentation patterns on Atlantic coastal forests in northern Spain

Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (northwestern Spain). We used orthoimages and a set of standard landscape metrics to determine transitions between land cover classes and to examine forest distribution patterns. Eucalypt plantations showed the greatest increase in area (197%) over time. Furthermore, transitions to eucalypt plantations were found in all major land cover classes. Forest showed a net decline of 20% in total area and represented 30% of the landscape area in 2003. Forest losses were mainly due to eucalypt plantations and the building of a water reservoir, while forest gains were due to increases in shrubland, meadows and cultivated fields which had been recolonised. Forest patch size and core area decreased, and edge length increased over time. In turn, increases were obtained in mean distance between forest patches, and in adjacency to eucalypt plantations and to a water reservoir. These results suggest an increase in forest fragmentation from 1957 to 2003, as well as a change in the nature of the habitat surrounding forest patches. This study shows that land use changes, mostly from eucalypt plantation intensification, negatively affected forested habitats, although some regeneration was ongoing through ecological succession from land abandonment.

Multispectral image analysis of glaciers and glacier lakes in the Chugach Mountains, Alaska

The Chugach Mountains contain the largest nonpolar alpine glaciers in the world and include a wide variety of glacier types: some are land terminating; some calve variously into tidewater, lakes, and rivers; some are heavily debris covered; some are surge-type, whereas others are neither debris covered nor surge type. Nearly all are retreating, thinning, or both, though some rare ones are advancing, and some are thickening at high elevations. To assist the further documentation of changes, we establish an inventory of glaciers in the eastern Chugach Mountains. Several case studies of diverse glacier types showcase remotesensing applications and are used to derive new knowledge of their current states and dynamical behavior. Several of these glaciers currently discharge into the Copper River and can be used to understand the processes governing glacier damming of large rivers. The Copper River, along with other major valley outlets from the Copper River Basin, was dammed several times by ice during the Pleistocene, forming a lake 10,000–20,000 km2 in area, called Glacial Lake Ahtna. Insights from the modern Childs, Miles, and Allen Glaciers—each of which fronts the Copper River—show that damming is not easily accomplished; direct encroachment, complete crossing, and successful damming require very low river discharge and probably introduction of abundant rock debris from a landslide onto the glacier. The last century has involved degradation of the Little Ice Age piedmont lobes of many valley glaciers in the Chugach Mountains and especially its Copper River corridor. These glaciers are generally losing over a meter per year of surface elevation. In another chapter highlight, we have found that crenulation and chevron folding of medial moraines does not require surging, as is commonly assumed; rather, the deformation can occur by flow diversion, without any surge activity, into ice-marginal lakes—a process we term a glacial aneurysm.

Prestige Marine Pollution: A GIS Tool

The accident and sink of the tank ship Prestige, that occurred offshore of the Galicia coast (northwest Spain) on November 2002, caused a large oil spill with important ecological and economic consequences for the Galician and Cantabrian littoral. Different data sets obtained through monitoring of the oil spill by over flight observation, satellite data, measurements from buoys and modelling of oceanic parameters (e.g. temperature, salinity, density, pH, fluorescence, dissolved oxygen) have been integrated into a Geographic Information System (GIS) for their access and study. The use of this GIS will allow the civil authorities and the scientific community to manage and to generate thematic cartography and to perform spatial and geostatistical analysis of the data in order to better analyze these marine pollution scenarios.

Geohazards and Geographic Information in the Coast of Tarragona (Spain)

The increasing amount of people that every year visits the coastal areas makes necessary to carry out a detailed analysis of all the processes that occur in these areas, in order to avoid the damages that the natural processes can cause.