With Earth Day celebrated on April 22 each year to mark the anniversary of the modern environmental movement, music publication Billboard published a list of 10 acts that have tried to make a difference to the environment over the past 12 months:

1. Jack Johnson
Hawaiian-born singer/songwriter Jack Johnson, a lifelong surfer, recently built a recording studio insulated with used denim and powered in part by solar panels at the Los Angeles HQ of his Brushfire Records, a cosy single-family home. Trucks and coaches on his 2008 tour will run on biodiesel, and venues are required to comply with his rules on cutting waste and recycling.

2. Willie Nelson
Country music star Willie Nelson's BioWillie biodiesel fuel, which is already sold in about six U.S. states, will add a key location when Willie's Place at Carl's Corner, Texas, opens this year. The truck stop, off the truck route from the Mexican to Canadian border, is billed as the biggest green truck stop in the United States with all fuels having some percentage of biofuel.

3. Mana
Mexican rock group Mana's nonprofit Selva Negra foundation, launched in 1994, has projects ranging from saving endangered species like the sea turtle to reforestation efforts. The group's most ambitious proposal to make environmental and ethics classes part of the curriculum for all of Mexican schoolchildren.

4. Dave Matthews Band
The U.S. rock band, through environmental nonprofit Reverb, has calculated the CO2 emissions from every stop on its upcoming summer tour and purchased the renewable energy credits to make up for the footprint left by each venue, hotel, flight, tour vehicle and even fan travel. Fans can sign up online for a carpool.

5. KT Tunstall
Last September, Scottish singer/songwriter KT Tunstall partnered with record label Virgin to create a 100% post-consumer waste recycled and chlorine-free booklet for her CD Drastic Fantastic. She also began work on the greening of her London home, as well as completing a carbon-neutral U.K. tour.

6. Pearl Jam
Pearl Jam drummer Matt Cameron last year played a January benefit for flood victims in Central Washington, while guitarist Stone Gossard helped plant vegetation in a Seattle park ravaged by English Ivy.

7. Serj Tankian
The "System of a Down" frontman-turned-solo artist has founded website skyisover.net to connect fans to environmental and social justice organisations. He also founded a nonprofit, Axis of Justice, with former "Rage Against the Machine" guitarist Tom Morello and is working with environmental nonprofit Reverb to ensure his current tour leaves only a small carbon footprint.

8. Radiohead
Delivering their album In Rainbows as a price-optional digital download before putting a physical product in stores last year prevented the manufacture and disposal of thousands of CDs. The British band travels unwillingly and when they do leave home, Thom Yorke and his bandmates partner with consulting firm Best Foot Forward to help reduce their carbon footprints.

9. Missy Higgins

Australian singer/songwriter Missy Higgins spent two weeks traveling across the United States in a hybrid Prius this year, posting web documentaries of stops at locations like the National Centre for Atmospheric Research in Boulder, Colorado, and the Mountain View Montessori School, a green elementary school.

10. The Roots
The Roots have taken autographing to a new level. At this year's edition of their annual pre-Grammy Awards all-star jam session, the Philadelphia-based hip-hop crew gave away signed compost bins in an effort to promote the practice.