Environment
of the Nazca and Ica Valleys
The Nazca Valley is unique among the numerous coastal rivers of the
Peruvian littoral because it is actually the confluence of many rivers
whose passage to the sea was blocked by upheaval of the coastal hills.
The Rio Grande de Nazca is the portion of the river that flows from
the interior valley, where the merging of rivers takes place, to the
Pacific coast. There is little or no delta formation where the Rio Grande
de Nazca meets the sea, as nearly all the alluvial sediments are deposited
in the interior basin and along the lower courses of the individual
rivers.
The Nazca and Ica rivers are fed by summer rains in the highlands. Watercourses
may otherwise be dry for parts of the year. In the 1940s the Ica
river was diverted just above the Hacienda Ocucaje, rendering the previously
fertile lower valley a desolate wasteland. In places along the Nazca
and sister rivers, the watercourse falls into subterranean aquifers
created from the soluable limestone and sandstone bedrock. These underground
rivers channel much of the water through the hottest and most inhospitable
parts of the lower valleys, where they might otherwise suffer complete
evaporation before reaching the Rio Grande.
0-600m (0-1800 ft.)
|
"Chala" zone: Seasonally variable: avg. at
21.3 degrees celcius.
Avg. rainfall= 0-25mm/yr.
|
600-2000m (1800-6000 ft.)
|
"Yunga" zone: Typically hot and dry.
Avg. rainfall= 25-100mm/yr.
|
2000-3600m (6000-10800 ft)
|
Highland zone
Avg. rainfall = 100-300mm/yr.
|
3600+ (10,800 ft.)
|
Approximate treeline--Avg. rainfall = 300-500mm/yr.
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More content to come...
For
now visit the virtual reality
gallery of ceramics, the Nazca
Valley Image Page, or view a satellite
image of Peru.