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“Magredo” means “poor soil”, that is arid and poor of water because of the stones, even if the rainfall here makes Friuli Venezia Giulia the rainiest region in Italy.
Foto Vaccher
In summer time, the arid meadows of the Magredi look bare and burnt by the sun, creating a landscape similar to some of the barren moors of the Southern Italy or to the continental steppe of the Eastern Europe.
The gravelly deposits of the rivers Cellina and Meduna creates a series of deposit cones spreading out from the mountains feet towards the plane. The main of these alluvial structures is dominated by the alluvial fan which is named after the above mentioned rivers and which with its wide architecture extends from Montereale Valcellina to Cordenons and Pordenone like a fan. In the pictures taken by the satellites, it looks like a huge white stain in the middle of the provincial district.
The fluvioglacial streams at the end of the last ice age gave the main contribution to the creation of this imposing gravelly mattress. With the gradual rising of temperatures, the streams gained strength and new erosional power, directly fed by the melting Alpine glaciers.
The alluvial deposits of these streams represent the main structure of the high plain and substrate where the Magredi of the river Cellina extend. They have the features of the Alpine forelands and have been recently inserted into the list of EU’s “Sites of Community Importance”, due to their original natural contents and environmental importance.
Foto Vaccher
The Cellina-Meduna Magredi are located in the western part of the high Pianura Friulana (‘Friulian Plain’) and spread out from a “cloth” of gravelly lands which wraps the mountains feet up to the boarder with the line of the Risorgive (‘Resurgences’). Their gravels are the result of the millenary wash erosion carried out by the streams onto the relieves lying behind. These streams carry away the rock fragments torn off from the mountains, turning them slowly into rounded and smoothed stones. When they reach the plain and, therefore the slope is decreased, they loose their power becoming lazy and free to wander. So, at the outlet of the deep Alpine valleys, the watercourses loose most of the heaviest and coarsest materials they are carrying, spreading them in a fan shape just like the free hand of the plumber when he sows broadcast. In the first strip of these deposits, the waters are completely reabsorbed through the gravels, creating a typical arid landscape without surface hydrography.
The most distinctive feature of the Magredi are the stones (in Friulan, ‘claps’), which the extraordinary peculiarity of this environment derives from, as well as its particular micro-climate and, as a consequence, its fauna. It is the stones, which are permeable, that make water disappear, the same water that then emerges again in the resurgence area.
Besides the stones, the Magredi environment is characterised by large meadowlands, mainly comprised of grasses and shrubs such as the blackberry bush (robus), the rock buckthorn (rhamnus saxatilis) and the dog rose. This steppe aspect is caused, besides the stony soils, by the ruinous action of the periodic floods against the vegetation and the soil itself. These floods were even greater in the past.
In addition, the steppe aspect is also due to men’s deforestation and spread of grazing.
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