| Achada Plateau | |
| Other Name: | Planalto da Achada |
| Coordinates: | 38.4589°N -28.2761°W |
| Range: | Mid-Atlantic Ridge |
| Elevation M: | --> |
| Surface Elevation M: | --> |
| Highest Point: | 1072m (3,517feet)[1] |
| Highest Elevation: | Caveiro |
| Length: | 30km (20miles) |
| Type: | Volcanic fissure |
| Last Eruption: | 1720 (Mistério da Silveira)[2] |
The Achada Plateau (Portuguese: Portuguese: Planalto da Achada) is an extensive volcanic mountain range located on Pico Island, Azores. It is a protected area with many valuable features that characterize the Azorean landscape. It is included in two Natura 2000 sites, one of which is classified as an Important Bird Area.[3] Part of the plateau also includes a ramsar wetland. It is one of the three main geomorphological units that comprise Pico Island.[4]
The Achada Plateau is located on the highlands of Pico, the highest and second largest island on the archipelago of the Azores. The extensive volcanic mountain range, located in the eastern half of the island at a mean altitude of 750m (2,460feet), stretches 30km (20miles) from Lagoa do Capitão (northeast of Mount Pico) to the easternmost part of the island. It is characterized by the steep slopes that limit it to the south and north and by the presence in the axial zone of the range of various volcano-tectonic alignments of cinder and spatter cones and eruptive fissures (typical of a basaltic fissural volcanism).
The volcanic cones, totaling around 190, have very varied dimensions and shapes, usually with associated ʻaʻā-type drains, which flowed towards the coast. Some cones show craters (sometimes occupied by small ponds) that are multiple, elongated or have several eruptive mouths, which reflect the associated tectonics.[5]
The Achada Plateau is one of the most valuable natural sites on the Azores. It hosts one of the last intact remnants of the original temperate mixed forests that covered the archipelago before the arrival of humans and the following deforestation and introduction of exotic species. It is listed as an Important Bird Area, several birds species make home in the peat bogs, ponds and lakes of the formation.[6]
Part of the central plateau was designated a Ramsar wetland in 2008 due to its ecological importance. Bodies of water include: Lagoa dos Grotões, Lagoa da Rosada, Lagoa do Paul, Lagoa do Landroal, Lagoa do Caiado, Lagoa do Peixinho and Lagoa Negra.[7]
The plateau is part of two Natura 2000 sites: The Special Conservation Zone of Mount Pico, Prainha and Caveiro; and the Special Protection Zone of the Central Zone of Pico.[8]
Due to its altitude, the plateau has a significantly different climate when compared to the rest of the island. According to Köppen, Achada has an oceanic climate, with cool to warm summers and chilly to mild winters. In the warmest month – August – temperatures vary between 19- at day to 12- at night and in the coolest month – January – from 10- at day to 6- at night.[9]
The area is subject to intense orographic lift which makes precipitation thoroughly abundant, humidity high (around 90%) and cloudiness persistent. It gets between 3000mm5000mm of precipitation per year, making it the rainiest area in the Atlantic Ocean (though most of the precipitation is actually from drizzle). There is a noticeably drier season in the summer, influence of its proximity to the Mediterranean Basin.
The plateau is characterized by two types of landscapes:
The plateau is also an important area for many resident and migratory bird species, especially the Azores wood pigeon. Most commonly found are the Azores chaffinch, the common snipe, the Eurasian teal, the American wigeon, the ring-necked duck, the mallard, the American black duck, the snow bunting, the grey heron, the grey wagtail, the common buzzard, the Atlantic gull, the wagtails and the Eurasian woodcock. Less frequent specimens include the Western Azores goldcrest, the Eurasian wigeon, the Eurasian blackcap, the European robin, the Azores blackbird, and the Atlantic canary. Rare specimens include the northern pintail, the American bittern, the blue-winged teal, the American coot, the tufted duck, the Wilson's snipe, among others.[10] [11]