Restoring Hong Kong's oyster reefs, one abandoned oyster farm at a time

Clean water and healthy ecosystems are becoming increasingly difficult to come by. With floating islands and other inventions, eco-entrepreneur Bruce Kania thinks that biomimicry - such as reconstructing wetlands and growing biofilms - can tackle the toughest of water problems.

Farmers in Vietnam face rising sea levels but rejected the city's water engineering projects. They prefer gradual measures to cope with climate change so scientists have allowed the farmers to steer the conversation.

Louisiana and Vietnam both need affordable solutions to rising sea levels. Leaders from Vietnam visited Louisiana to compare ideas.

Geography and climate change challenge the viability of sea-level cities in Vietnam, but architects, researchers, and urban planners work together to find creative solutions. One architect in Ho Chi Minh City designed green roofs to absorb the rainwater that causes floods.

The World Conservation Union estimates that 40 percent of the more than 40,000 species it tracks on its Red List are close to extinction and this problem requires humans to change their behavior to fix it. Rare’s the Pride Campaign uses social marketing to attract attention and communicate the conservation message between local communities and government entities. The Pride Campaign has been replicated around the world for different conservation efforts to protect biodiversity.

Property rights, circumscribed jurisdictions, and conflicts with neighbors exacerbate Native American efforts to restore tribal land and resources. Some tribes have found success by tapping into a trend of support from the government and conservationists.

Prescription drugs are greatly polluting the national water supply, causing researchers to begin looking for a method to better filter water and dispose of unused medicine.

New water management technology implemented along the Columbia has significantly helped the fish population - specifically salmon - return to healthy numbers and has restored much of the community and industry that revolves around the river, including for native peoples.

Warming water has led to the collapse of coral reef systems in the western Indian Ocean, essential to fisheries, protecting shorelines, and reducing beach erosion and sea-level rise. Marine scientists from Nature Seychelles, as part of an international project to protect and restore the reefs, are promoting varieties of coral that they have found to be resistant to the rise in temperature.

Tottenville, on Staten Island, will get oyster-friendly breakwaters and a dune system as part of post-Sandy rebuilding efforts. The oysters will help revive the ecosystem and sustain the long-term fishing economy.