“Rios
Sabor e Maçãs” is included in a Mediterranean valley system located in
the Northeast of Portugal. This site has been designated both as an SCI
(PTCON0021; surface area: 33482 ha) and an SPA (PTZPE0037; 50687 ha),
with partially overlapping areas.
The area is
characterized by highly seasonal and dry climatic conditions, with low
annual values of precipitation (400-800 mm), and predominant shallow
soils (leptosols). Furthermore, the landscape features are dominated by
the vigorous physiography of the valleys, and the spatial variability of
environmental conditions and processes contribute to the existence of
relevant local ecological values.
The study area hosts
populations of more than 40 species listed in the Annexes of the Habitat
and Bird Directives. Several forest types representing Annex I habitats
are common on slopes (9330, 9340 and 9560*) and along river margins
(91B0, 91E0* and 92A0). In rocky margins of the main rivers, the relict
habitat 5110 occurs in mosaic with saxicolous grasslands (6160). In the
courses and flood margins of temporary rivulets, wet grasslands (3280,
3290) and tall herb formations (6420) form dense mosaics. Most of the
area is dominated by open scrublands (5210, 5330) in mosaic with annual
and perennial dry grasslands of habitat 6220*. In steep slopes and
vertical stone walls, saxicolous formations are common (8220). In the
highest elevations, oak forests (9230), old chestnut groves (9260) and
heaths (4030) can be found.
Recent changes in the
landscape result from the partial abandonment of agriculture and of
extensive husbandry, and afforestation with both native species (conversion
of agricultural land) and exotic species (intensive forestry), and are
related to demographic decline, private land owners’ absence, and
increasing activities such as hunting and fishing. Currently, a large
hydroelectric dam is being constructed at the downriver end of the site,
so profound transformations will occur in the main valley and habitats
and species will be severely affected by flooding.
Main data available
for the site:
Landsat TM and ETM+
Habitats map (2005)
Land cover maps
(COS90, COS00; COS06)
Species records
Moderate resolution
long term time series (MODIS)
Several thematic
ancillary datasets are also available for the site, namely climate,
hydrography, geology, soils, socioeconomic and demographic data,
agrarian censuses (farm structural survey data), forest surveys (national
inventory), wildfires, and road network.
