Over the past few decades, an incredible amount of time and money has been spent trying to remove populations of "non-native" plants. But according to a panel of ecologists, climate change, urbanization and other changes in land use have largely invalidated the theory that foreign plants are inherently harmful to their newly adopted ecosystems.

On December 22nd, 2008, a Tennessee Valley coal-fired power plant ruptured, sending nearly one billion gallons of coal ash into a nearby river, where it turned to sludge. That hazardous sludge was shipped to a landfill site outside Uniontown, Alabama — an area whose demographic is too poor for the kind of political clout that would block the move. The question is: do communities like Uniontown ever really get a say in where hazardous waste goes?  

The Great Lakes' ecosystem could soon be facing a major threat by the Asian carp, an invasive fish. But the carp have a determined opponent: 11-year-old Ellie Moskowitz.

It's been four days since BP put a cap on the Deepwater Horizon oil well and, with cautious optimism, people have begun talking about recovery. But just because the oil has stopped gushing doesn't mean the damage is done. In fact, say some scientists, more harm is soon to come.

Fifty years ago, a young Jane Goodall first walked into the Gombe National Park in Tanzania. Things have changed dramatically. She talks about the changing political, environmental and ecological landscape in which she has dedicated her life's work of studying the social and familial interactions of wild chimpanzees. She says that what used to be a densely forested area is now "an island of forest surrounded by cultivated fields and people struggling to survive."

In 1979, an explosion on the Ixtoc 1 oil platform caused the world's worst accidental oil spill 50 miles off Mexico's Gulf Coast. 140 million gallons of oil gushed into the Gulf. It took more than nine months to cap the leak. The BBC has launched a series, "Oil and Water" in which they will explore the impacts of an oil-based economy in various locations around the world. As a part of the series, BBC reporters traveled to Mexico's beaches only to find the effects of the Ixtoc spill are still being felt today, more than thirty years after the explosion.

• OIL SPILL TAKEOUT: We check in with Captain Kathy Wilkinson, who operates an eco-tourism business in southern Mississippi. She describes the nervous anticipation in the air as Mississippians wait for the oil slick to break on the coast. Check out her blog post for more on the spill's business impact.
• LISTENERS RESPOND: Over the phone and on the web, Takeaway listeners weigh in on the oil spill and share their favorite movie moms in honor of Mother's Day.

The Deepwater Horizon disaster isn't the first time massive amounts of oil have gushed into the Gulf of Mexico. In 1979, an exploratory well, Ixtoc I, blew out in the same waters, amounting to the second largest oil spill in world history. And other spills in 1979, 1990 and 1993 have dumped thousands of barrels of oil into the Gulf of Mexico. How do these past events inform what may come next, for both human residents of the Gulf coast and the environment as a whole?

Economists say the Deepwater Horizon oil spill could cost tens of billions of dollars both in cleanup and lost business revenue. Industries in the affected area are already taking hits, as fishing operations shut down and tourism slows. David Kotok, chief investment officer for money management firm Cumberland Advisors, says in the best-case scenario the cleanup will take years and the economic impact will be mostly felt in a handful of states on the Gulf of Mexico.

The oil spill in the Gulf of Mexico is currently estimated to be roughly the size of Puerto Rico; wind and currents are slowly moving it towards the shores of Louisiana, Mississippi and Alabama.

President Obama traveled to Louisiana yesterday for a first-hand briefing on the oil spill in the Gulf of Mexico. The "Deepwater Horizon" oil rig exploded on April 20th, rupturing its well and eventually sinking into the Gulf. An estimated 200,000 gallons of oil are gushing into the Gulf each day, as federal government and BP officials frantically explore options to contain the spill.

Tomorrow, in the midst of a string of health care town halls, President Obama is squeezing in a family trip with Michelle and his daughters. The Obamas will visit the Grand Canyon and Yellowstone National Park. The former mayor of West Yellowstone, Montana, Jerry Johnson, tells us how the locals are responding to the impending presidential visit.

We are also joined by historian Douglas Brinkley, author of The Wilderness Warrior: Theodore Roosevelt and the Crusade for America, with a look at the nation's national park system and the ecological streak that makes up President Teddy Roosevelt's lasting legacy.

It has deep red flesh. It measures more than six feet high. It blooms only about once a decade. But the most memorable thing about the "Corpse Flower" at the Huntington Botanical Garden is that it gives off the stench of rotting flesh. The Takeaway is joined by Garden Director Jim Folsom, who's in San Marino, California, with the flower, Amorphophallus titanium.

Watch the crowds gather around a blooming corpse flower in this time-lapse video.

Food writer Mark Bittman's first book, "Fish: The Complete Guide to Buying and Cooking," explored the glory of piscine cuisine. But when offered the opportunity to revise the book, he declined. Overnight shipping of loads of fish cargo, farm-raising and over-fishing have turned buying and eating fish into an ethical and ecological quagmire. Mark Bittman joined The Takeaway to explain his reasons for being more selective about which fish end up on his plate.

Food writer Mark Bittman's first book, "Fish: The Complete Guide to Buying and Cooking," explored the glory of piscine cuisine. But when offered the opportunity to revise the book, he declined. Overnight shipping of loads of fish cargo, farm-raising and over-fishing have turned buying and eating fish into an ethical and ecological quagmire. Mark Bittman joins The Takeaway to explain his reasons for being more selective about which fish end up on his plate.

Trouble viewing this video? Check out the YouTube version.

Today is Earth Day, and many of us are patting ourselves on the back for going green. But despite your wise decisions to buy CFL lightbulbs, zero VOC paint, and phospate-free soap, it turns out most products that advertise themselves as green are barely scratching the surface. But there's good news! Advances in new sciences like industrial ecology mean we are on our way to a greener future. Here to explain what that all means and what small steps you can really take, The Takeaway talks to Daniel Goleman, author of Ecological Intelligence: How Knowing the Hidden Impacts of What We Buy Can Change Everything.

Databases like Good Guide and Skin Deep can help consumers choose products that are green and healthy.

For more tips on saving the planet, watch the Planeteer Alert below.

When you think of dinosaurs, what comes to mind? Hulking creature? Gargantuan teeth? What about something the size of a small house cat? In a story that everyone's inner child will love, researchers in Canada have found North America's smallest carnivorous dinosaur. Paleontologist Nick Longrich joins The Takeaway to talk dinos and break down what the continent's ecosystem looked like millions of years ago.

Anyone who has watched wildlife documentaries may know that animal behavioral patterns are tracked by inserting microchips into the animals' bodies. This is tricky, because it requires tranquilizing the animal in order to place the chip. But new technology now allows for non-invasive research. Science journalist Jim Robbins joins The Takeaway to explain how scientists are using technology and animal products, like poop, to learn everything they can about wildlife without even touching the animals.

For more, read Jim's piece on DNA-powered wildlife research in the New York Times article, Tools That Leave Wildlife Unbothered Widen Research Horizons.

If you want to do your own wildlife surveys, you'll need to be able to match scat with the critter that created it. To bone up, watch this video.