Agricultural Settlement and Land Use in Mountains - Mountain Geography: Physical and Human Dimensions - page 543

plada (900-1,800 m; 3,000-6,000 ft) is best suited for coffee, cut flowers, and shorthorn
cattle. Higher still, the thinning atmosphere produces a sharp cold season in the tierra
fria (1,800-3,600 m; 6,000-12,000 ft) that requires hardier crops such as wheat, barley,
apples, pears, and dairy cows. Above this, at the uppermost limit of agriculture near the
treeline, the tierra helada (up to 4,600 m, or 15,000 feet) is best suited for crops that
tolerate a short and frenetic growing season. These include grains and tubers, sheep,
and the South American trio of camelids (llama, alpaca, and vicuña). Cold temperat-
ures and a short growing season above the tierra helada preclude cultivation, although
seasonal grazing of livestock occurs in many meadows during the brief summer. This
change in land use with elevation can still be observed today, although some products,
particularly maize and cattle, occur in more than one zone depending on the individual
habitat, microclimate variation, and genetic manipulation.
Other scientists have since refined von Humboldt's early work in Latin America
(Stadel 1992; Lauer 1993). In addition, analogous models from elsewhere include
the Staffelsysteme (staggered exploitation) in the Karakoram Mountains (Kreutzmann
2000), Almwirtschaft in the Alps (Streifeneder et al. 2007), and variants in the Himalaya
(Stevens 1993), Atlas Mountains (Miller 1984), and Papua New Guinea (Ohtsuka et al.
1995).
It is important to remember that, as with von Humboldt's scheme, the extraordinary
diversity of mountain habitat results in significant digression from any theoretical mod-
el. As discussed in Chapters 7 and 8, mountains produce a remarkable array of ecologic-
al habitats resulting from the interplay of physical factors. These include geologic and
edaphic conditions, temperature inversions, slope and aspect, valley flooding, elevation,
latitude, mountain mass effect, relief, wind, and frost at any time of year. Zimmerer
(1999), for example, believes that although altitude plays an obvious role in determining
crop patterns in Latin America, agricultural landscapes are comprised of overlapping
patchworks shaped by human and ecological processes over long periods. The advent of
new roads, genetically altered crops and animals, mechanization, and the lure of extern-
al wage-earning jobs also sway the vertical distribution of crops and animal husbandry.
There are striking differences in settlement history between various mountain
ranges, as discussed in Chapter 10. North America is unusual in that the highlands re-
main relatively unpopulated, except for rapidly expanding resort towns and some foot-
hill regions adjacent to urban centers (e.g., Sacramento, California, and Denver, Color-
ado). In fact, much of this region, particularly the highest elevations, consists of pro-
tected parks and wilderness where most traditional economic activity is forbidden. Yet
another trend here, and in other developed-world mountains such the Alps, is wide-
spread migration to lowland cities that correlates with a deemphasis on mountain agri-
culture. In these regions, the explosive growth since 1950 in recreation and its associ-
ated service industries has almost totally replaced farming and herding as the economic
mainstay. In contrast, Old World and South American mountains have long supported
dense populations. The strategies used by various cultures to overcome the limitations
of these often minimally productive landscapes are illuminating and provide insight into
the nature of mountains themselves. Some may depend upon sedentary agriculture and
livestock, while at the other extreme are nomads skilled in animal husbandry.