//archives

Biogeochemistry

This category contains 43 posts
Fig2_oceanbites

Funny happenings in the tropical Pacific

Nitrous oxide is a powerful greenhouse gas made by environmental microbes. In the ocean, microbes making this greenhouse gas live in zones with little to no oxygen. Scientists always thought that Bacteria were making this gas. Recently, a team from the UK set out to explore this hypothesis in the Eastern Tropical Pacific, and found that actually a totally different type of microorganism, Archaea, were making the nitrous oxide. These are important findings since global warming and increased human inputs in the ocean are causing low oxygen zones to expand, potentially making even more greenhouse gas!

Where is all the methyl mercury coming from?! 
(Creative Commons photo by Patrick Kelley)

A mercurial tug o’ war in Antarctic sea ice

DNA from bacteria living in Antarctic sea ice provides a clue to the mysterious origins of methyl mercury in seawater in the Southern Ocean.

Figure 1: H. trimaculatus (source: https://commons.wikimedia.org/wiki/File:Hippocampus_trimaculatus,_Osezaki.jpg)

From Wastewater to Seahorses to the Medicine Cabinet

Pollution of metals could be getting into the tissue of seahorses–the very tissues that are used to make a special Chinese medicine. Now scientists fear that the metal pollutants could harm the patients who take the medicine. Read more to find out what they learned about the accumulation of metals in seahorse tissues.

Figure  1: the "rainforest of the sea"

Do coral reefs help fight climate change?

Coral reefs are called the rainforests of the sea for their stunning biodiversity. But can they, like forests on land, absorb CO2 and help reduce global warming?

Figure 1: The Deepwater Horizon oil spill (Creative Commons)

The Dirty Blizzard: how oil from the Deepwater Horizon spill reached the seafloor

Oil floats on water, yet oil spills are still devastating for marine life living on the seafloor. How does it get there? A new study shows that it can hitch a ride on sinking particles during an algae bloom, turning marine snow into a “dirty blizzard”. Read on to find out more!

Figure 1: algae blooms off the coast of England (Creative Commons)

Why iron fertilization hasn’t worked

Fertilizing the ocean with iron to help algae store more carbon in the deep sea was once heralded as a solution for global warming. But decades of research has suggested it doesn’t work as advertised. What went wrong? Read on to find out!

Microscope image of dust particles (Creative Commons)

Dust detectives: tracing the origins of Antarctic ice core debris

Tiny dust particles punch above their weight by delivering nutrients to remote ecosystems. A new study uses the chemical fingerprint of dust particles to retrace their origins and how this important process has changed over the last 800,000 years. Read on to learn more!

The Illuminated Ruminant.

Of whales and cows: the baleen whale microbiome revealed

Scientists sequenced the microbiomes of several baleen whales that are strict carnivores and found some startling similarities to the microbiomes of terrestrial herbivores.

Figure 2 – The Elwa dam study site in WA on September 17, 2011(Photo by Ben Cody, https://commons.wikimedia.org/w/index.php?curid=16563772).

Solving Big Dam Problems

The US has a lot of dams. Probably far more than you ever imagined possible. Many of these dams are around 100 years old. How long does it take to restore a riverine ecosystem to a more natural state after a century of alteration by a dam? Scientists addressed a portion of this question by measuring the return of salmon to a section of river previously blocked by the dam and the use of the nutrients delivered by these salmon by other organisms in the area.

Complete nitrification by a single bacterium - kind of a big deal, guys!

One to tango: a bacterium that does the work of two in the nitrogen cycle

Scientists report bacterial species capable of performing the two-step process of nitrification, traditionally thought to exist only as a division of labor between two functionally distinct bacteria.

11465351655_daa3995993_z

A Slick Study! Natural Oil Seeps and Chlorophyll

Oil seeps are naturally occurring sources of oil to the marine environment. This study looks at the impacts of oil seeps on chlorophyll concentrations near the surface of the ocean and the results are pretty slick!

The ship’s marine technician Mike and I deploying the first SOCCOM float in rough conditions in the Southern Ocean.

Sailing the Southern Ocean for science

Hear about my adventures living on an icebreaker on the Southern Ocean, deploying ocean robots to understand the chemistry and biology of the Southern Ocean.

Oil spill

Oil spill first responders: how tiny algae cultivate oil-degrading bacteria

After an oil spill, millions of oil-degrading bacteria are on the scene almost immediately. But how do they survive in regions with no oil pollution? A new study shows that tiny cyanobacteria produce enough oil to maintain a small population of oil-degraders, capable of rapidly multiplying in response to the sudden influx of oil from a spill. This short term oil cycle sustains a first line of defense against catastrophic ecological damage from spills.

limacina-spiral-611

Rapid changes in the Southern Ocean threaten ecosystems

Rapid acidification of the Southern Ocean could occur in the next 30 years with potentially huge impacts to local ecosystems.

Healthy calanoid copepod (Diaptomus spp.). Summer 2000.

Estimating carbon sequestration from plankton poop

Copepod fecal pellets—plankton poop—transport carbon from the ocean surface to the deep where it is stored for thousands of years. A new study presents a framework for scaling up our understanding of this process from observations of single organisms to the global ocean.

oceanbites_cael_october_fig1

Ocean eddies suck carbon out of the atmosphere, thanks to plankton

When phytoplankton sink into the deep ocean, they take carbon with them, storing CO2 away from the atmosphere. This new study suggests that ocean eddies may play an important role in getting this tiny organisms to sink!

CoverPhoto

Microbes foil attempts to increase deep ocean carbon sequestration

Most carbon emitted to the atmosphere ends up in the ocean, much of it in organic molecules. While most is quickly respired back to CO2, a fraction is transformed by microbes to apparently stable compounds that persist in the ocean for centuries. Could we manipulate the microbial community to hold even more? A new study suggests this is unlikely because the deep ocean is already holding as much organic carbon as it can handle.

http://www.sportdiver.com/article/news/global-reef-expeditions-assess-coral-reef-health

How a whole reef community’s response to OA is impacted by the individual responses of different players

Researchers from California used a unique ex situ experiment to monitor two near identical reef communities in different concentrations of dissolved carbon dioxide to observe the unique responses of community members and their roles in the whole community response.

http://oceanexplorer.noaa.gov/okeanos/explorations/ex1104/logs/dailyupdates/media/daily_updates_aug14_600.jpg

What is the source of organic molecules in Von Damm vent fluids?

The origin of life is with out a doubt a fascinating topic of discussion and debate, intensified by the fact that there is no definitive answer (yet). A group of WHOI scientists present a mechanism and environment where organic compounds can be formed from inorganic ones via abiotic production. The plausibility of their suggestion is strengthened by the present day occurrence of said mechanisms in hot spreading centers where ocean plates are formed at the bottom of the ocean.

http://walkingwith.wikia.com/wiki/Precambrian_Era

A 2.5 billion year old story about iron in the ocean, told by a rock

New light has been shed on the possibility of an alternative iron sink than previous thought prior to the oxygenation of the oceans 2.45 billion years ago. The findings could affect our interpretations of the early seawater chemistry, nutrient cycling, and trace metal distribution in the Precambrian.

oceanbites photostream

Subscribe to oceanbites

@oceanbites on Twitter