An Introduction to Mountains - Mountain Geography: Physical and Human Dimensions - page 10

homes has been directly linked to high rates of bronchitis and other respiratory diseases
in millions of mountain homes.
Work seasons are short in the mountains, and skilled labor forces often lacking,
especially in areas characterized by the out-migration of young people (this volume,
Chapters 10, 11, and 12). This is common in many mountain areas, from the Appalachi-
ans to the Hindu Kush, and many traditional mountain cultures are being rapidly as-
similated into mainstream cultures as modern communication technologies and tourists
reach even the most remote mountain villages. Yet emigrants often send remittances
which can be vital sources of income and investment, and when they return, they may
bring new ideas which can often be combined with traditional ideas and approaches,
contributing to sustainable development. Examples include new means of producing
and marketing the many high-quality and high-value products for which mountains are
known, including textiles, food, and drink. In all of this, women are of critical import-
ance to home life, the work force, farm maintenance, and as retainers of traditional
biodiversity knowledge—yet they typically remain marginalized with regard to decision
making, equity, and education (Byers and Sainju 1994; Ives 1997).
A key set of challenges derives from the fact that mountains are naturally dynamic
environments, and low-frequency/high-magnitude events such as volcanic eruptions,
landslides, debris flows, and glacial lake outburst floods (GLOFs) are capable of causing
immense damage (Hewitt 1997; this volume, Chapter 5). One of the more extreme ex-
amples of catastrophic events was the 1970 Huascaran earthquake and debris flow in
Peru, which buried the town of Yungay (population 20,000) within minutes and killed an
estimated 80,000 people throughout the region (Browning 1973).
As many of the larger glaciers have melted in the Hindu Kush-Himalaya (Bajracharya
and Shrestha 2011), hundreds of new glacier lakes, holding millions of cubic meters
of water, have been created. Usually contained by dams of loose boulders and soil,
these lakes present a risk of GLOFs. Triggering factors for GLOFs include “lake area
expansion rate; up-glacier and down-valley expansion rate; dead-ice melting; seepage;
lake water level change; and surge wave by rockfall and/or slide and ice calving”
(Watanabe et al. 2009). GLOFs unleash stored lake water, often causing enormous dev-
astation downstream that can include high death tolls as well as the destruction of valu-
able farmland and costly infrastructure (hydroelectric facilities, roads, and bridges).
Examples include the 1941 outburst flood above Huaraz, Peru that killed nearly 6,000
people within minutes (Hambrey and Alean 2004; Carey 2005, 2010); the 1985
Langmoche outburst in the Sagarmatha (Mt. Everest) National Park, Nepal, which des-
troyed the $2 million Thami hydroelectric facility, hundreds of hectares of cropland, and
dozens of bridges downstream (Vuichard and Zimmerman 1986; Byers et al. 2013; By-
ers 2013); and the 1998 outburst of the Sabai Tso in the Hinku valley, Makalu-Barun
National Park, Nepal, that destroyed trails and seasonal settlements for nearly 100 km
downstream (Cox, 1999; Osti and Egashira 2009).
A number of other physical attributes of mountains argue not only for their import-
ance to policymakers in the immediate term but also for the special consideration neces-
sary to ensure their sustainable use to meet the demands of both mountain people and
those living downstream in the years to come (Ives et al. 1997; this volume, Chapter 12).
For example, while mountains may seem indestructable—and are occasionally sources
of great destruction—they include some of the most fragile ecosystems in the world