Almost four decades ago, Gaviotas was started as a sustainable community in one of the harshest places in South America. It has worked -- largely because of trees

In 1971, United Nations Food and Agriculture Organization scholar Paolo Lugari started an eco-social experiment in the barren Llanos plains east of the Andes in Colombia called Gaviotas.

Situated in one of the most extreme, most inhospitable climates in South America, Gaviotas was envisioned as a sustainable, self-sufficient village in an area that Lugari called "just a big, wet desert."

"They always put social experiments in the easiest, most fertile places," Lugari said. "We wanted the hardest place. We figured if we could do it here, we could do it anywhere."

"The vision gestating in Paolo Lugari's subconscious involved his hunch that someday the world would become so crowded that humans would have to learn to live in the planet's least desirable areas," wrote Alan Weisman, author of "Gaviotas: A Village to Reinvent the World."

Today, Gaviotas is a thriving eco-village of about 200 people. They farm organically. They use wind and solar power. Since 2004, Gaviotas has been 100% fossil fuel-independent.

The residents also enjoy free housing, schooling and community meals. Shockingly, considering the region's dangerous political situation, there are no weapons, no police, no jail and no mayor.

But though these elements would make any social experiment a success, perhaps the most remarkable accomplishment of Gaviotas is the planting of 1.5 million Caribbean pine trees and palm trees, a bold initiative that has helped to restore the receding rainforest border closer to what it was in pre-Colombian times. The various results of this new tree growth have been incredible.

The transpiration of the trees has helped to engender more productive rainfall cycles. The shade of the trees has inspired the return of many rainforest species that were once native to the region. Additionally, the residents of Gaviotas enjoy a sustainable source of income from the resin harvested from the trees.

The United Nations named Gaviotas a model of sustainable development. The Colombian novelist and Nobel Prize laureate Gabriel Garcia Marquez called Lugari the "inventor of the world."

A new study by a team of researchers from the University of Wisconsin-Madison, the University of Minnesota, Stanford University, Arizona State University and The Nature Conservancy has found that "nature's capacity to store carbon, the element at the heart of global climate woes, is steadily eroding as the world's farmers expand croplands at the expense of native ecosystem such as forests," according to the press release.

Considering this disturbing fact -- and as the world population surges towards an estimated 9 billion by the year 2050 and global warming continues the steady increase of the planet's surface temperatures -- Gaviotas stands as one shining example of how things could be different.