She says changes such as migration away from rural areas are allowing more women to find work and provide for their families. But migration is also taking resources from those rural areas. And developers who harvest large amounts of fish or trees are affecting the country’s natural resources.

“You know the changes are, in a way they’re helping people because they’re giving them opportunities, but at the same time they’re not cognizant of the impact that it’s having on people’s lives.”

Kalyanee Mam says these impacts are the reason she made her film. She says she wanted to show the beauty of Cambodians’ daily life. That life will be lost, she says, if people are not more aware of the effects of globalization.

Kalyanee Mam’s film, “A River Changes Course,” won the world cinema prize for documentary at the Sundance Film Festival this year. It is also playing at the Environmental Film Festival in Washington, DC.

Flo Stone founded the DC Environmental Film Festival in 1993. It lasts 13 days and is showing 190 films from 50 countries this year.

“We have films this year about the Amazon, about the Ganges, the Mississippi in America, the Rhine, a whole series of films on the Rhine winding through Europe, and other rivers in Africa and Asia.”

Ms. Stone says film is a powerful way to get people talking about the importance of rivers and other environmental issues.