ROME, Italy — Most people wouldn’t consider an earthquake to be an environmental issue. But while the tremors that shattered Haiti early this month have nothing to do with the island’s degradation, the extent of the suffering they unleashed is a direct result of the country’s ecological woes.

The reason can be seen from the sky. The devastated nation shares its island with the Dominican Republic, but misfortune always seems to strike on its side of a border that is demarcated by an abrupt shift from lush green to bare brown. While the Dominican Republic has largely managed to preserve its trees, Haiti has lost 98 percent of its forest cover.

In 2004, Hurricane Jeanne struck the Dominican Republic, and killed 18 people. In Haiti, where the storm didn’t even make landfall, more than 3,000 lives were lost under floodwater and mudslides. Deforestation had left the slopes too weak to be able to retain the downpour. But while some of the extra body count can be attributed to barren hillsides giving way, the true cause goes deeper. The country’s environmental troubles have become entangled in its economic and political problems, making all of them harder to fix.

It’s no coincidence that Haiti is both the poorest country in the western hemisphere and the most environmentally devastated. Decades of poverty, population growth and near anarchy have stripped the countryside of its forests and split farms into small, infertile plots. “What you see in Port-au-Prince — the concentration of people in the slums, which creates violence, which creates disease — it’s because the people cannot produce more in the countryside,” Max Antoine, executive director of Haiti’s Presidential Commission on Border Development, told me when I visited the country in 2007.

If deforestation has made the country poor, the resulting destitution exasperates the environmental degradation. Forests disappear. The slopes lose their soil. Farm land slips away. Entire villages disappear under mudslides. Roads and bridges are wiped away. The slums continue to swell. The country sinks deeper into poverty. Pressed to survive, another farmer chops down another tree to sell in the city as charcoal. “It’s not a vicious circle,” said Philippe Mathieu, the Haiti director for the Canadian charity Oxfam-Quebec. “It is a spiral. Each time you make a turn, you have less space.”

This month’s tragedy showed how tight that space has become. On Sunday, the official death toll climbed to 150,000, and the government suspects the figure could double. Many lost lives could have been avoided if buildings in the capital had been built to withstand earthquakes. Many others could have been saved if systems for emergency response and medical care had been in place. As a point of comparison: In 1989, an earthquake of exactly the same strength struck San Francisco at almost exactly the same time of day. The death toll was 63.

But unlike San Francisco, Port-au-Prince doesn’t have building codes. And if it did, its residents couldn’t afford to comply; most concrete blocks in the capital are handmade, with cheap, light materials. Even the buildings built by the United Nations couldn’t withstand the quake. As for coordinating an emergency response, Haiti wasn’t able to maintain much of a police force — never mind staffing a system of first responders or supporting a strong medical infrastructure. So when the earthquake struck, the residents of the capital were left pretty much on their own.

The way that Haiti’s challenges have interlocked has made them particularly difficult to overcome. The country has tree-planting programs, but they haven’t been able to keep up with the rate of deforestation; nor are they likely to as long as the poor depend on the charcoal trade for their income. Even before the earthquake, Haiti’s government was unable even to keep order on the streets of the capital. It’s no surprise that it couldn’t solve two seemingly intractable problems at once.

As the rescue effort in Port-au-Prince wraps up, the focus is turning to rebuilding the country. There’s talk of reconstructing its agriculture, its educational system, its housing, its infrastructure. The effort is expected to cost billions of dollars. It’s also expected to take decades. That’s enough time to grow some trees.

Stephan Faris is GlobalPost's environmental columnist. This article is based, in part, on his book, "Forecast: The Surprising — and Immediate — Consequences of Climate Change," which was published in paperback in September.