Can green spaces and reconnecting with nature actually promote measurable good health, both physical and  mental? Tom Stoner thinks so, and he’s putting his money where his mouth is. He and his colleagues at the TKF Foundation, through a program called Nature Sacred, have built dozens of temporary green refuges, primarily in the Washington-Baltimore area, in hopes of alleviating the stresses of urban living.

They are built at universities, in tough inner-city neighborhoods, in hospitals and prisons. And while there is plenty of anecdotal evidence that people derive countless health and psychological benefits from a green setting, Stoner wants to prove it scientifically.

The foundation just announced $4.5 million in funding for six projects, where scientists from a number of different disciplines will work to study the effects of specially designed spaces on people living in an urban environment, or who are otherwise under stress. The team of designers and scientists will work in locations that cover a wide spectrum of environment and experience.

"Of course, we have no idea how it’s going to come out," says Stoner, adding that the project will go on for three years."It’s a sense that these spaces are important and intimate. It’s about our individual, personal relationship with nature. People write about how peaceful they feel."

At Walter Reed Hospital in Bethesda, Maryland, the Green Road Project will create a wheelchair-accessible area of pavilions and landscaped gardens in a wooded area on the hospital campus, where hundreds of soldiers are receiving treatment for traumatic injuries suffered in the line of duty. The Legacy Emanuel Medical Center in Portland, Oregon, will create a "healing garden" in a space that is currently a hardscape terrace. The research will follow three groups of patients, families, and nurses to gauge the effects of the natural environment on their stress levels and mood.

Stoner says that with the development of better tools to assess stress levels and neurological response to stimuli, the time has come to measure that ineffable relationship. He thinks that proof of the health benefits of well-designed green space could go a long way toward encouraging better funding of these kinds of places to maintain our physical and mental health in a rapidly urbanizing world.