Ecology

The impact of nitrogen released from the burning of fossil fuels and widespread use of fertilizers is much greater that previously recognized. Scientists say the impact even extends to remote alpine lakes. --by Margaret Coulombe

For decades there has been a controversy about whales eating fish in the tropics. The debate has been at the heart of policy decisions about the culling of whales and is pivotal to the future of commercial whaling in the region. New research, however, shows that culling whales in an attempt to restore fish populations is not scientifically sound. --by Margaret Coulombe

The desert city of Phoenix depends on an extensive canal system to bring water to farms and homes. But artificial lakes and canal systems along with extensive groundwater pumping have had unintended effects on the ecosystem, scientists say. --by Margaret Coulombe

Lake Tanganyika is an ecological jewel at the heart of desperate human misery. Prohibitions on fishing--designed to protect the fragile ecosystem--have angered local fishermen. These kinds of tensions between conservationists and local people are common. ASU researchers are working to strike a balance. --by Adelheid Fischer

The Vortis Insect Suction Sampler vacuums bugs off of plants. Researcher Stan Faeth uses the tool to study what kind of bugs inhabit particular plants, and their relationships to them. --by Margaret Coulombe

Microbial symbionts live in the guts of animals, the interiors of corals, and the roots of plants. They help plants take up nutrients and help cows break down cellulose, but they can also be harmful to their hosts. Stan Faeth wants to understand the relationship between symbionts, their hosts, and their role in everything from conservation to cancer cures. --by Margaret Coulombe

Historians aren't known for interdisciplinary collaborations. But Paul Hirt is getting environmental historians out into the field and working with anthropologists, ecologists and geographers. He hopes to increase their understanding of the complex interactions between humans and the landscape. --by Adelheid Fischer

The sky islands borderlands of the Southwest is a unique area harboring such a broad range of life that Conservation International has designated it a hotspot of global diversity. Once sparsely settled, the sky islands borderlands are now undergoing economic, ecological, and social upheavals. Environmental historian Paul Hirt is looking at the region's past to help citizens, businesses and governments manage its present and future. --by Adelheid Fischer

Nitrogen pollution from agricultural and urban runoff is a serious threat to ocean ecosystems. Nitrogen, in the form of nitrates, could generate algal blooms, create oceanic "dead zones" and kill coral, fish and shellfish in coastal zones. Researchers have discovered that small organisms in streams and rivers can filter out excess nitrogen before it reaches the oceans. However, overloading streams with too many nitrates reduces their filtering ability. --by Margaret Coulombe

When you visit the beach, the ocean always looks the same--but that doesn't mean it isn't changing. A new study has taken a comprehensive look at human impacts on marine ecosystems, including coral reefs, estuaries, and pelagic waters. The results show that none of Earth's oceans have escaped human influence. Now, oceanic maps from the study can help policy makers determine where human activities are most likely to cause negative effects. (Read the full story) --by Margaret Coulombe