High-mountain glacial lakes of Aigüestortes, Lleida Pyrenees

Environmental conditions

This habitat occurs in a high-mountain Atlantic environment shaped by altitude and relief; in the park, precipitation usually exceeds 1,000 mm annually and usually falls as snow in winter.

Distribution and scope

This profile is delimited to the lakes of Aigüestortes i Estany de Sant Maurici National Park, in the high Pyrenees of Lleida, between the Noguera Pallaresa and Noguera Ribagorçana basins; they occur in main valleys and glacial cirques.

Structure

The lake landscape comprises basins on valley floors and in high cirques, associated with glacial cirques and U-shaped valleys, some of them hanging or stepped; certain infilled lakes give way to wet meadows and meanders.

Ecological processes

During glacial periods, masses of ice occupied the valleys and eroded the relief, forming cirques and basins; later, sediment accumulation in some lakes promoted their infilling and the development of wet meadows with winding watercourses.

Seasonal changes

Snowfalls are frequent in the park between November and April, and some temporary ponds may dry out toward the end of summer.