Friday, March 10, 2017

Mount Etna 2016

The name Etna originated from the Phoenician word attuna meaning "furnace" or "chimney".

Mount Etna is an active stratovolcano on the east coast of Sicily, Italy, in the Province of Catania, between Messina and Catania. It lies above the convergent plate margin between the African Plate and the Eurasian

Elevation: 3,350 m
Prominence: 3,329 m
Area: 1,190 km²
Province: Province of Catania
Mountain range: Nebrodi

 More than 25% of Sicily's population lives on Etna's slopes, and it is the main source of income for the island, both from agriculture (due to its rich volcanic soil) and tourism.
 Etna's eruptions have been documented since 1500 BC, when phreatomagmatic eruptions drove people living in the eastern part of the island to migrate to its western end. The volcano has experienced more than 200 eruptions since then, although most are moderately small. Etna's most powerful recorded eruption was in 1669, when explosions destroyed part of the summit and lava flows from a fissure on the volcano's flank reached the sea and the town of Catania, more than ten miles away. This eruption was also notable as one of the first attempts to control the path of flowing lava.

The Catanian townspeople dug a channel that drained lava away from their homes, but when the diverted lava threatened the village of Paterno, the inhabitants of that community drove away the Catanians and forced them to abandon their efforts. An eruption in 1775 produced large lahars when hot material melted snow and ice on the summit, and an extremely violent eruption in 1852 produced more than 2 billion cubic feet of lava and covered more than three square miles of the volcano's flanks in lava flows.

 Etna has also produced pyroclastic flows, ash falls, and mudflows, but the lava flows are the most immediately hazardous type of activity, especially to the city of Catania. While the flows themselves usually do not move fast enough to threaten humans, they can cover large areas and destroy crops and buildings. In the event of a large flank (fissure) eruption, evacuating the inhabitants of towns and cities near the volcano would be a huge challenge.
 On 3 December 2015, an eruption occurred which climaxed between 03:20 and 04:10 local time. The Voragine crater exhibited a lava fountain which reached 1 km (3,300 ft) in height, with an ash plume which reached 3 km (9,800 ft) in height. The activity continued on the following days, with an ash plume that reached 7 km (23,000 ft) in height that forced to shut down Catania airport for a few hours.

Before 2001, Mount Etna erupted at an average of once every 1.7 years. Since 2001, a period of higher activity has kept the volcano more active; there have been eruptions every year since except in 2007.

The Parco dell’Etna (Etna Park) was established as a Regional Nature Park by Decree of the President of the Sicilian Regional Authority in May 1987. The property includes part of this Park, comprising the zone defined as an integral reserve. In addition, nine Natura 2000 sites overlap the property to various degrees, providing additional protection for 77% of the area under European legislation.

 The regulations provided within the Decree provide for adequate protection of the key values of the property. Since the completion of a land acquisition process in 2010, 97.4% of the property’s area is in public ownership (region or communities). In contrast, 56.6% of the buffer zone is privately owned.

The management of the property is coordinated by Ente Parco dell’ Etna, established as the managing authority of Etna Park by Decree of the President of the Sicilian Regional Authority in May 1987, working in close cooperation with the Regional Authority of State Forests and the Regional Corps of Forest Rangers (Corpo Forestale). Management is guided by a long-term management plan and Triennial Intervention Programmes.

 Public access to the top of Mount Etna may be officially prohibited for safety reasons, although this regulation has been difficult to enforce. Organized recreational activities such as mountain biking and horse / donkey riding require advance authorisation. Although they appear to be limited at present, they need to be well monitored and managed to avoid negative impacts such as erosion and disturbance of wildlife. No dogs are allowed in the property and illegal hunting appears to be under control.

At the base, the mountain is mostly occupied by crops, especially citrus (up until 500 meter high).
Once, the lower slopes of the volcano were occupied by carob and wild olive, but in recent times these were replaced.
At higher altitudes (600 - 1000m above sea level) the vegetation was at a time characterized by forests of holm oak (Quercus ilex).

Today these forests almost completely disappeared due to anthropogenic influence.
They were substituted by vineyards, olive trees, almonds and pistachios on the western side and hazel on the northern side.
 The holm oak woods are still present on the western slope where one can also find plenty of Oriental hackberry (Celtis tournefortii).
 Between 1000-1500m, the mountain is characterized by forests of downy oak (Quercus pubescens) and chestnut trees.

On the eastern side one can find forests of Turkey oak (Quercus cerris). Above these forests there are black pines, for example the pine forests of Serra la Nave.
Above the 1500 meter mark, pine trees as well as beech trees (Fagus sylvatica) can be found.
In some areas, especially on the eastern side there are trees of Etna birch (Betula aetnensis), considered by some endemic to Mount Etna.
 Above the 2450m mark very few plants can survive that adapted to the harsh environment like the French sorrel (Rumex scutatus). Above 3,000m altitude the continuous eruptive activity of Etna prevents any form of plant life to thrive.

Mount Etna broom Genista aetnensis 

Broom is first thing to grow after each eruption

The terminal branches have a tendency to droop and weep.
From mid to late summer is produces an abundance of sweetly fragrant pea shaped yellow flowers. 

 Young plants are typical of brooms but as they age the shrubs develop into small trees with a greenish bark.

 Genista aetnensis or Mount Etna Broom is a large shrub or small tree endemic to the island of Sicily, in Italy.

It is a very common constituent of the Mediterranean shrubby vegetation but especially around the lower slopes of Mount Etna.

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