Geography and Environment
General
1. The core of the Central Andean Culture Area encompasses roughly the
central third of the western portion of South America, although at certain
times other regions to the north and south were brought politically and
economically within its sphere.
2. This area comprises modern
Peru and Bolivia between 4 Degrees and 18 Degrees South of the Equator (roughly
1000 miles N-S), and extends from the eastern Andean slopes to the Pacific
Ocean (roughly 200 miles E-W). The area is circumscribed by the ocean in the
west by equatorial rain forest to the north and east and by the Atacama Desert
to the south.
3. This entire region except
the in the extreme east falls within the Pacific climatic zone. It is consequently much dryer in general
than the equatorial forest regions to the east, and encompasses a very
different ecological pattern
4. In terms of human settlement, there is a greater tendency toward permanently-sedentary, agricultural society than in the forests to the east where hunting and gathering remains strong and agriculture is of the more mobile “swidden” type.
5. The central Andean area is
one of great contrasts. Moving inland
from the Pacific shoreline, zones of coastal desert, highland, and forest run
from north to south down the western side of the South American continent, all
within a 200 mile E-W span. This
overall pattern brings with it extreme contrasts of heat and cold, rainfall and
altitude, thus creating a great diversity of ecological zones in a relatively
small area.
6. Compounding the dramatic
volatility of the area, the Andes constitute one of the most active tectonic
zones in the world and earthquakes, tidal waves, and volcanic eruptions all
occur fairly frequently.
7. These general factors play
important roles in shaping the physical (subsistence, settlement, technical)
and mental (political, religious) domains of Andean people’s experience.
Specific
Coastal Ecology
Coastal shores
The coastal environment is formed by the conjunction of two forces –
oceanic and terrestrial.
The cold inshore current the Humboldt Current washes the western side
of the continent with its greatest effect along the Peruvian coast. In conjunction with the prevailing climatic
and topographic conditions this plays a major role in shaping the distinctive
coastal environment.
1. The Humboldt Current removes
the warm inshore water and allows its replacement by upwelling of cold water
from the deeper ocean.
2. The cold water carries
nutrients to the surface (especially phosphates and nitrates).
3. These nutrients feed vast
quantities of microscopic marine plants and organisms.
4. These in turn feed small
fish, especially anchovy.
5. Larger fowl, fish, and sea
mammals feed on the smaller animals creating one of the most abundant marine
resources in the world.
6. Finally Man exploits the
entire food chain.
Inland coastal desert
1. Warm southern trade winds
blow over the cold Humboldt Current, causing condensation and dense clouds.
2. The wind blows the clouds
over the warm equatorial landmass whose heat causes the air to expand and hold
the large moisture content until the clouds hit the high western facing slopes
of the Andes Mountains, where they precipitate rain.
3. However, there is no rain
along the level coastal plains. These
constitute one of the most arid deserts in the world.
4. The rain runs back down to
the coast in the form of numerous coastal rivers that traverse the coastal
desert.
5. Thus the coast presents a
distinctive combination of small but extremely fertile river valleys separated
by wide stretches of desert.
6. At times of El Nińo this
normal climatic regime reverses, the cold ocean current recedes, the normal
marine fauna are displaced, and the coastal climate becomes rainy leading to
catastrophic floods and great damage to the economic and social infrastructure.
Coastal Diversity
1. Within this coastal pattern
there is diversity with coastal valleys in the north being larger and closer
together and supporting greater irrigation agriculture potential and population
intensity than in the south where valleys are more widely separated, indented
and carry less water.
2. This provides greater
northern potential for:
- agricultural development.
- population.
-economic integration.
- political integration.
3. Consequently the North Coast
of Peru was one of the two centers of pre-European cultural and social
florescence.
Highland Ecology
General
1. The Andes Mountains run N-S
in two parallel ranges with altitudes commonly exceeding 20.000 ft, enclosing
intermountain basins and high altitude river valleys that commonly reach
10-12,000 feet of altitude.
2. There is consistent rainfall
permitting rain-fed agriculture throughout the Andes
3. The steep slopes necessitate
terracing to prevent soil erosion.
The Vertical Archipelago
1. Andean highland life was conditioned by dramatically diverse
climates and topography.
2. In order to obtain the full
range of nutrients highlanders had to control various altitudinal zones, each
producing a different set of crops and each with a distinct set of settlement
qualities.
3. Thus highlanders developed a
way of life that extended their social as well as economic control over various
zones extending across the entire sloes of the Andes from lowlands river
valleys to high grassy plains of the altiplano where only specialized
tubers grew and llama and alpaca herding was possible.
4. We will discuss the specific
strategies used in this “archipelago” ecological adaptation in later lectures.
Highland Diversity
1. In the north the mountains
were of lesser height, received more rainfall and were broken by transverse
ranges, making communication and integration difficult.
2. In the far south in the Titicaca Basin the two Andean ranges opened
into a huge high grassland plain – the altiplano. This region of southern Peru and adjacent
Bolivia constituted a uniform environmental zone. People of this region developed specialized subsistence, economic
and political strategies shaped by the vertical archipelago to construct
elaborate social and political integration.
3. Thus the southern altiplano
represented the second great center of Andean civilization.