Navigation Links
R.I. nitrogen cycle differs in bay and sound

PROVIDENCE, R.I. [Brown University] Rhode Island's geography is famously small, but new measurements of the nitrogen cycle in its waterways suggest that even over a small distance, differences can be huge. Scientists report that the nitrogen-converting process anammox is almost completely absent in Narragansett Bay, even though it is going strong in Rhode Island Sound only 15 miles off the coast.

The novel and somewhat surprising finding, documented in the journal Limnology and Oceanography, raises intriguing questions about why the bay seems inhospitable to an important environmental process, said corresponding author Jeremy Rich, assistant professor of ecology and evolutionary biology at Brown University.

"Past research suggested anammox might be increasing in importance in the bay, but there was not any data to back it up. What we're showing is it's barely even there," Rich said. "What's wrong with the nitrogen cycle in lower Naragansett Bay? Why don't we have anammox? Have we disturbed it to the point where we are missing this process?"

Anammox anaerobic ammonium oxidation was only recently discovered and remains incompletely understood. It is one of two ways that nitrogen in various forms in seafloor sediments is converted back into its inert form (N2) that composes 80 percent of the atmosphere. The other process is denitrification. This conversion is not only a key step in the Earth's vital nitrogen cycle, but also it contributes to the health of waterways by removing excess nitrogen that can fertilize harmful algae blooms.

For their study, researchers including lead author Lindsay Brin sailed to the sites on the fishing vessel Virginia Marise every season over two years. They took measurements and collected sediment cores from the Providence River Estuary, Naragansett Bay (into which the estuary feeds), Rhode Island Sound (into which the bay opens), and the neighboring Block Island Sound.

They looked at key measures of oxygen, nitrate, nitrite, and ammonium and organic matter in the sediments and measured environmental conditions such as salinity and temperature at the sites. They also performed experiments on the sediment cores to determine their potential denitrification and anammox rates.

What they found was that in the sounds annamox contributed between 8 and 42 percent of the N2 produced (denitrification produced the balance), while annamox produced no more than 4 percent of the N2 in sediments from the estuary or the bay.

Anammox activity wasn't seasonal in either locale, they found, and the waters were comparably salty. What did differ, however, was that compared to the sediments of the sounds, the estuarine and bay sediments had less oxygen mixed in and therefore less nitrate. Those factors were associated with less anammox activity.

So the questions Rich is now asking come down to why oxygen and nitrate levels vary in sound and bay sediments.

One of Rich's observations has been that in the sound's sediments, but not the bay's, little shrimp burrow and effectively promote the mixing in of oxygen.

It's speculation to blame a lack of the shrimp for the bay's dearth of anammox, Rich said, but it is a new hypothesis worth consideration. In the meantime, what the new study suggests is that Rhode Island's bay waters somehow lack the proper conditions to activate an important process in returning nitrogen from the sea to the air.


Contact: David Orenstein
Brown University

Related biology news :

1. Nitrogen pollution, climate and land use: Why what we eat matters
2. Patented research remotely detects nitrogen-rich explosives
3. Study resolves controversy over nitrogens ocean exit strategies
4. Nitrogen source determined significant for inflorescence development in Phalaenopsis
5. Nitrogen-tracking tools for better crops and less pollution
6. Nitrogen management studied in greenhouse pepper production
7. Floods didnt provide nitrogen fix for earliest crops in frigid North
8. Nitrogen fertilizer remains in soils and leaks towards groundwater for decades, researchers find
9. Microbes capture, store, and release nitrogen to feed reef-building coral
10. Nitrogen has key role in estimating CO2 emissions from land use change
11. Global nitrogen availability consistent for past 500 years, linked to carbon levels
Post Your Comments:
Related Image:
R.I. nitrogen cycle differs in bay and sound
(Date:4/13/2016)... , April 13, 2016  IMPOWER physicians supporting ... are setting a new clinical standard in telehealth thanks ... By leveraging the higi platform, IMPOWER patients can routinely ... pulse and body mass index, and, when they opt ... and convenient visit to a local retail location at ...
(Date:3/29/2016)... RATON, Florida , March 29, 2016 ... or the "Company") LegacyXChange "LEGX" and SelectaDNA/CSI Protect are ... DNA in ink used in a variety of writing ... theft. Buyers of originally created collectibles from athletes on ... through forensic analysis of the DNA. ...
(Date:3/22/2016)... PROVO and SANDY, Utah ... (NSO), which operates the highest sample volume laboratory in ... Tute Genomics and UNIConnect, leaders in clinical sequencing informatics ... the launch of a project to establish the informatics ... NSO has been contracted by the ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... --  EpiBiome , a precision microbiome engineering company, today ... from Silicon Valley Bank (SVB). The financing will allow ... drug development efforts, as well as purchase additional lab ... been an incredible strategic partner to us – one ... provide," said Dr. Aeron Tynes Hammack , EpiBiome,s ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... STACS DNA ... Technical Leader at the Arkansas State Crime Laboratory, has joined STACS DNA as a ... STACS DNA team,” said Jocelyn Tremblay, President and COO of STACS DNA. “In further ...
(Date:6/23/2016)... 2016 Apellis Pharmaceuticals, Inc. today announced ... of its complement C3 inhibitor, APL-2. The trials ... dose studies designed to assess the safety, tolerability, ... in healthy adult volunteers. Forty subjects ... single dose (ranging from 45 to 1,440mg) or ...
(Date:6/23/2016)... June 23, 2016 ... 2016;12(1):22-8 Published recently ... peer-reviewed journal from touchONCOLOGY, Andrew D Zelenetz ... of cancer care is placing an increasing burden ... expensive biologic therapies. With the patents on many ...
Breaking Biology Technology: