“绿色空间”有助于减少贫困地区的犯罪

Keith Green has an unusual interest in empty, unused properties, even while he is on vacation.

Recently, Green, an American, was visiting Shanghai, China. He went out for dinner when he discovered something that made him stop and take a picture.

"Everyone else is taking pictures of the skyline," he told VOA. "I'm taking a picture of a vacant lot."

Most travelers do not seek out vacant properties. In Green's hometown of Philadelphia, Pennsylvania, vacant lots are often home to increased crime. People often leave trash or hide illegal weapons and drugs in them.

But Green is leading an effort to remove these problem areas from Philadelphia's low-income communities. In their place, he creates "green spaces," or areas that are like small parks, with plenty of trees or other plants.

It is a huge job. The city has an estimated 40,000 vacant lots.

Still, Green is seeing how a little green space can make a big difference in parts of the city that experience high levels of poverty and crime.

Green spaces reducing gun violence and depression

Recent studies published in major scientific journals have documented the effects of the program that Green heads. These studies have found that the program is leading to major reductions in gun violence and depression in some of the poorest parts of Philadelphia.

Gina South co-wrote those studies. She is an emergency department doctor at the University of Pennsylvania. Since her first years at the hospital, she has wanted to do more to help the people from these neighborhoods before they come to her severely injured.

"We took care of a lot of shooting victims and did a great job of treating their physical injuries," she said, "but did little to nothing to think about what was causing them to come in as shooting victims to us in the first place."

Several years ago, South became interested in the program Green directs at the Pennsylvania Horticultural Society, called Philadelphia LandCare.

The program employs local workers to clear the trash and some of the plants from vacant lots. Then they plant trees and grass, cut the grass twice a month, and surround the lots with fences with openings that welcome people in.

South said at first she did not fully believe that the changes would do much for the people living these areas.

But the more she and her coworkers investigated it, the more positive results they found.

In one study, they found people's heart rates decreased as they walked past cleaned-up lots. That shows their stress levels are coming down, a reaction "happening in people's bodies in response to what's in their neighborhood environment," South said.

Possibly the most notable results come from the group's study of 541 vacant lots in different places across the city. They were divided into three groups. One group got the full cleaning and greening treatment. One just got a few trash pickups. One group got nothing.

Around the cleaned and greened lots, crime decrease by nearly 10 percent overall. In the poorest neighborhoods, gun crimes fell by 17 percent and nearly 70 percent fewer people said they felt depressed.

"Those are big effects," said Northwestern University crime researcher Wesley Skogan, who was not involved with the study.

Cleaning and greening vacant lots removes "signs that nobody's watching, nobody cares, nobody's in charge," he added.

Improving vacant lots fits in with an idea called the "broken windows" theory. The idea is, disorder in the environment sends a signal that more disorder is acceptable, including criminal behavior.

The theory became problematic as it led to the creation of the "stop and frisk" method of policing. Under this method, officers hold and search anyone they believe may be involved in illegal activity, for whatever reason.

Cleaning and greening "is much closer just to fixing the...window," Skogan said. "It's a sign that someone's looking out for them. Someone's paying attention."

Unexpected results

The program is working better than even Keith Green expected.

"I didn't think it would work," he said.

Green had been doing community gardening with the Pennsylvania Horticultural Society as the LandCare program was getting started in the late 1990s and early 2000s. At the time, he was planting flowers and other plants and surrounding them with large fences "to keep people out," he said.

Meanwhile, the program was welcoming people into the green spaces.

"I was like, ‘That's not going to work. People aren't going to respect it,'" Green added.

"Then I started seeing people put picnic tables on it, putting garden areas in...They're not destroying it," he said. "Then I was like, ‘This can actually work.'"

Green said each lot costs about $1,600 to treat and about $200 per year to keep operating.

However, Skogan would like to see research showing how it compares to other methods of helping low-income neighborhoods.

"Probably nobody thought it was a bad idea to clean things up and put up fences," he said. "It's always a question of whether you do this versus something else."

Green said he gets calls from officials across the country and the world asking how a little green space can help improve their neighborhoods.

He said he sees people's way of thinking changing in neighborhoods where he is working. Children do not throw trash in the cleaned-up lots, he said. They pick it up.

That has been satisfying enough, he said. "But when you start throwing (in) these numbers, like, gun violence is going down, and people's heart rates are being reduced, people are exercising more...you're just like, wow."

I'm Anna Matteo. And I'm Pete Musto.

Steve Baragona reported this story for VOA News. Pete Musto adapted it for Learning English. Kelly Jean Kelly was the editor. We want to hear from you. How helpful do you think a program like this would be in your city or area? Write to us in the Comments Section or on www.hxen.net .