Environmental Change in the Mediterranean

Background

Mediterranean basin is important for environmental change as it is very sensitive and in a delicate state of balance - commonly flagged up in IPCC reports

5% change in rainfall in Med may cause desert conditions or woodland development

What makes up a landscape? - geology, climate (past and present), humans, vegetation (product of other 3 factors)

Lies on a climatic boundary between wet temperate N Europe and arid subtropical desert of N Africa

Not wet enough for deciduous woodland but not dry enough for desert conditions

Warming and drying of climate in the future could lead to widespread desertification

Region has been long exploited by humans - degradation and desertification through clearance of veg, changing land use/crop type, over-grazing and over abstraction of water

Area affected by many episodes of envrion change e.g. glacial/ interglacial cycles, S/T climate change (Little Ice Age) and human impacts

Change from steppe vegetation in glacials to dense woodland in interglacials

Tectonics

Characterised by basin/range topography:

• Range - mountains - formed from crustal rocks = metamorphic so hard to break down/erode e.g. Sierra Nevada
• Basin - low lying flat land between the ranges - young limestone (silts, clays and finer seds) infill these topographic lows = much more easily eroded

Med formed as a result of tectonic collisions - African, Iberian and European plates, started approx 20 million years ago

The capacity of the sea to get into basins is reduced due to increased infilling of sediments therefore see…