 |
|
|
|
|
The lake Garda |
|
|
|
 The Garda lake or Benaco, is the largest lake in Italy. It is 65m above sea-level, has an area of 368km sq., a perimetre of 51.6 km, and a maximum width of 17.5 km. It shares its borders with three regions, Trentino-Alto Adige, Veneto and Lombardia and the relative provinces of Trento, Verona and Brescia.
From the Veneto bank the Baldo range (Valdritta peak 2.218 m) extends North in Trentino with mount Altissimo of Nago and mount Stivo (2.218 m); at Riva one can find the characteristic Tooth of Brione as well as mount Rocchetta (1.521 m) which is aligned with mounts Palàer (1.078 m), Guìl (1.322) and Carone (1.621 m), followed by mount Tremalzo (1.974 m) and then towards the lower Giudicaries, mount Caplone (1.976 m). South of mount Bestone, which closes the gulf of Limone, lie mounts Cas, Denervo (1.459 m), Castello di Gaino, Pizzocolo (1.582 m).
South of Maderno the morphology becomes more gentle along the Valtenesi range and inland of Desenzano and Sirmione with morainic hills.
The main tributary of the lake is the river Sarca; other waterways are the Brasa, the San Michele (or Tignalga), the Toscolano and the Arìl, considered to be the shortest river in the world. The only distributary is the Mincio which runs from Peschiera to the Po.
The largest island is Garda (once called “dei frati” or “Lechi” or “Borghese), 1,100m long and 60m wide; others are the isle of San Biagio (or “dei Conigli”) opposite Manerba, and the isle of Trimelone at Brenzone.
|
|
|
 |
|
|
 |
|
|
 The geology
The present-day appearance of the Garda basin can be traced back to the activity of the glaciers of the Quartenary era which channelled into a pre-existing valley (originating probably from a tectonic rift or from a river) thus moulding its bed and its shores.
The mountains surrounding the lake, except for some basalts around the Sogno valley and mount Baldo, were formed from sedimentary calcareous rock attributed to both the Secondary and the Tertiary eras. Evidence of the fauna of those eras can be found in the shape of several different fossils such as Megalodon gumbelii, Vortenia solitaria, ammonites, ocean nummulites etc.
In the morphology of the lake bed one can distinguish two basins: a North-westerly larger one, that reaches a depth of 346m between Gargano and Magugnano of Brenzone, and the other South-easterly, the basin of Peschiera, which is much more shallow reaching a maximum of 78m opposite Bardolino.
The climate
The climate is mild, with episodes of dry heat that differentiate Garda from other pre-alpine lakes which are colder and more humid. Measurements taken from the “Pio Bettoni” observatory in Salò over the period 1954-1976, indicate the following data:
- average annual temperature of 13,3°C, with seasonal averages of 4,1°C in winter, 12,8°C in spring, 22,6°C in summer, 13,6°C in autumn;
- 10-12 days of frost a year;
- average annual atmospheric humidity of 71%;
- 2.050 hours of sunshine a year;
- annual rainfall of 1.180 mm, mainly in
Spring/Autumn; snow and thick fog are very rare on the coasts of the lake. These exceptionally favourable conditions are due to the mitigating influence of the mass of water which can reach a surface temperature of 25°C in Summer, whilst at a depth of 50 m, it has an average temperature of 13°C and of 8,5°C at 100 m.
|
|
|
|
|
|
|
|
|
|
 The flora and the fauna
From the underwater beds to the highest peaks, the flora of lake Garda boasts 2800-3000 species (nearly 50% of the species to be found in Italy), with mostly Angiospermae (2300-2400), followed by mosses (200), ferns (70-80) and finally Gymnospermae (20-30). Fungi and lichens are also numerous.
As regards larger plants (Spermaphyta), species adapted to mild climates (Mesotermophiles) are prevalent and typical of the mediterranean (oak, dwarf-oak, green, holm-oak, manna-ash); higher up one can find black hornbeam, chestnut and beech.
There are numerous native plants: Aquilegia einseleana, Aquilegia thalictrifolia, Geranium argenteum, Moheringia glaucovirens, Papaver rhaeticum, Saxifraga arachnoidea, Saxifraga tombeanensis, viola dubyana.
Amoung the exotic flora the most important are those grown for human consumption (olive and caper trees), for ornamental purposes (agave, camphor, palms, cedar) and for commercial purposes (mulberry, cypress, pine, nut, citrus, bay). The cane plant is still a common sight.
The lake’s typical fish include bleaks, vairons, tench, chub, rudd, eel, pike. There are also several types of protozoa, rotifers and small crustaceans. The depths of the lake are home to some of the more esteemed varieties: carp, lake-trout, true alose or papaline and lavarello. Amoung the animals native to the area are many insects and spiders, the mollusc Cinguliphera cingulata gobanzi, typical of theValvestino. (and amoung the fish, carp.)
|
|
|
|
|
|
|
|
|
|
 |
|
The weather |
|
29.08.2008
|
| 30 °C |
|
|
|
|
|
