Why Manhattan's Green Roofs Don't Work--and How to Fix Them
City rooftops covered with vegetation are seen as a way to reduce the urban heat-island effect and cut energy usage--but so far, the results have been unimpressive
Stories by Amy Kraft
Upstream Battle: Fishes Shun Modern Dam Passages, Contributing to Population Declines
A river study in the U.S. Northeast has found that many fish species are unable to use standard passageways to swim past dams on their spawning runs
