Making room for mountains.

Ask a hundred people at random what the most urgent environmental problems are, worldwide, and the responses are predictable--but not necessarily in accord with what a careful global view would tell us.

In all probability, one fundamental system would be entirely overlooked by our hypothetical 100 respondents. The earth's great mountain ranges--the Himalaya, Andes, Rockies, Alps--still occupy only a peripheral place in our awareness. We think of them as colossal realms of immutable rock and ice, with little role in the biological processes of the planet--and little vulnerability. But in fact, mountains play a critical and unique role in the life of the planet--as this issue's story on the Himalaya shows.

Their steep slopes make them geologically unstable, with huge climatic variability and ecological diversity over very short distances. As a result, mountain ecosystems are more prone not only to natural hazards--landslides, avalanches, earthquakes--than most other ecosystems, but also to human damage. While the political leaders and decision makers who live in the plains typically ignore these distinctions, they do so at their own peril--and at the peril of their downstream populations.

About 10 percent of the world's people live in mountainous regions, and another 40 percent depend on mountain environments for their water, power, timber, minerals or topsoil--and hence much of their food. The great rivers of Asia, which nurture and irrigate the continent's vast rice crops, bring their water and nutrients from the Himalaya. The Amazon and Madeira, similarly, are fed by the Andes. The environmental degradation of the mountains and the increasiug impoverishment of their inhabitants affects the earth--and its human population-profoundly.

So far, these threats have not reached the threshold of urgency in the tropical rainforests, where the slash-and-burn assault persists, or in the oceans, where pollution and overfishing decimate biological systems. But mountains are in trouble. And unlike other global features, they are not vet in the protective embrace of our consciousness. "The mountains have never had their Cousteau," says Dr. Jack Ives, professor of geography at the University of California at Davis.

Confronting the global challenges of sustainable development in mountain environments began only last year, with the inclusion of this priority in Agenda 21, the Rio Earth Summit's global blueprint for action on environment-and-development problems. At that time, the mountain agenda went virtually unnoticed by the gaggle of international media. But now it's time we began paying closer attention.

From the Himalaya to the Sierra, mountain ranges need to bc recognized not just as sloping examples of rainforests, grasslands, or deserts, but as major bioregional systems in their own right, presenting unique challenges that will require specific policies of their own.

We can start by creating a small agency within the United Nations Environment Programme (UNEP) to monitor both environmental and developmental indicators for mountain regions. Having a central source for gathering and publicizing these indicators will help galvanize international commitment to protecting the world's mountains and sustaining their people.