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A University of Windsor professor is among an international team of scientists examining what challenges and opportunities the future may hold for invasive species research.

Professor Hugh MacIsaac travelled to the University of Cambridge last fall along with 16 other ecologists to reach a consensus on what they believed to be the emerging trends, issues, opportunities and threats for invasive science.

At the Maji Agricultural Reservoir in Wonju, Gangwond-do, South Korea, that someone is Tae Kwon Lee. Lee regularly jogs around the reservoir. One day he noticed large black birds completely covering the small island in the lake. The black birds were great cormorants, a type of large water bird, and the trees on the islet were completely covered in the birds’ feces. As time passed, Lee made another observation: the lake suffered a severe algal bloom.

Algal blooms deplete oxygen in lakes, produce toxins, and end up killing aquatic life in the lake. This sequence of events got Lee wondering: Did the bird feces cause or contribute to the algal bloom?

About half of atmospheric carbon dioxide is fixed by ocean's phytoplankton, mainly picocyanobacteria, through a process called photosynthesis. Picocyanobacteria are tiny, unicellular microorganisms that are abundant and widely distributed in freshwater and marine environments. A large portion of biologically fixed carbon is formed by picocyanobacteria at the sea surface and then transported to the deep ocean. But what remains a mystery is how colored dissolved organic matter which originates from plant detritus (either on land or at sea) makes it into the deep ocean. A team of scientists from the University of Maryland Center for Environmental Science and around the world potentially found a viable marine source of this colored material.

The ocean sequesters massive amounts of carbon in the form of “dissolved organic matter,” and new research explains how an ancient group of cells in the dark ocean wrings the last bit of energy from carbon molecules resistant to breakdown.

A look at genomes from SAR202 bacterioplankton found oxidative enzymes and other important families of enzymes that indicate SAR202 may facilitate the last stages of breakdown before the dissolved oxygen matter, or DOM, reaches a “refractory” state that fends off further decomposition.

Planting trees is a popular strategy to help make cities “greener,” both literally and figuratively. But scientists have found a counterintuitive effect of urban vegetation: During heat waves, it can increase air pollution levels and the formation of ozone. Their study appears in ACS’ journalEnvironmental Science & Technology.

Previous research has shown that planting trees in cities can have multiple benefits, including storing carbon, controlling storm water and cooling areas off by providing shade. This has spurred efforts in cities across the U.S. and Europe to encourage the practice. However, it’s also known that trees and other plants release volatile organic compounds, or VOCs, that can interact with other substances and contribute to air pollution. And when it’s hot, plants release higher levels of VOCs. Galina Churkina and colleagues wanted to investigate what effects heat waves and urban vegetation might have on air pollution.