Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New system can measure productivity of oceans

11.02.2005


Researchers at Oregon State University, NASA and other institutions announced today the discovery of a method to determine from outer space the productivity of marine phytoplankton – a breakthrough that may provide a new understanding of life in the world’s oceans.



Phytoplankton are the incredibly abundant microscopic plant forms that provide the basis for most of the marine food chain, half the oxygen in our atmosphere and ultimately much of the life on Earth. They have rapid growth rates and are constantly being produced and consumed in huge amounts – but until now, it was impossible to determine their rate of growth on any broad, useful scale.

The new findings, which were developed with funding from NASA and the National Science Foundation, have been published in Global Biogeochemical Cycles, a professional journal. A group of scientists also explained the new study today in a national teleconference. "The new information on phytoplankton growth rates and biomass will greatly advance our understanding of the Earth’s oceans," said Michael Behrenfeld, a research professor in the Department of Botany and Plant Pathology at OSU.


"We don’t have the satellite technology available yet to fully take advantage of this new approach," he said. "But ultimately this system should have a great potential to effectively monitor phytoplankton productivity and understand the physical and chemical forces that drive it."

Although too tiny to see, phytoplankton have a net annual production that’s comparable to the total amount of terrestrial plant life on Earth, scientists say. They produce about 50-65 billion tons of organic matter each year, and in the process absorb carbon dioxide and pour oxygen into the atmosphere.

Their abundance dictates the location and health of most marine fisheries. They play a critical role in marine water quality issues, can help regulate climate, are affected by climate, and are responsible for red tides and other harmful algal blooms. The very basis of sustainable ecological systems is almost impossible to understand without a good grasp of phytoplankton productivity, and its implications for global climate change.

Behrenfeld is an expert on phytoplankton, and has studied them from their molecular and metabolic pathways to their measurement from outer space. "It was only in the late 1800s that we even realized these tiny plants formed the base of the marine food web," Behrenfeld said. "By the 1950s, we had figured out how to accurately measure their production and use observations of chlorophyll to determine their biomass. But until now, we’ve never been able to measure their rate of production over large areas."

That production can be enormous, and highly variable. Phytoplankton biomass can double in as little as one day, and it’s routine for the entire mass of phytoplankton in an area to either be consumed by other life forms or die and sink to the ocean bottom in less than a week. "Obviously, there’s a very tight coupling between phytoplankton production and its consumption or death," said Emmanuel Boss at the University of Maine, a co-author on the paper. "So it’s almost impossible to really understand what’s going on in the oceans without understanding that rate of production. Now we have a way to do that."

The researchers accomplished this by moving beyond the old standard for monitoring phytoplankton, the observation of chlorophyll. "The growth rate of phytoplankton can change dramatically based on such factors as water temperature, nutrients and light," Behrenfeld said. "And it’s the growth rate of phytoplankton we have to know, to really take the pulse of the oceans. That’s the missing piece of the puzzle." The new approach is based on the premise that the ’greenness’ in phytoplankton – its level of pigmentation per cell – is a reflection of its growth rate, said David Siegel of the University of California, Santa Barbara, the third author on the paper. The researchers have discovered a means to measure phytoplankton biomass from ocean light scattering properties and infer growth rates from simultaneous measurements of how green the individual phytoplankton are, all from outer space.

The mathematics behind this approach, the researchers say, is conceptually similar to technology that’s used in a home supply or paint store when someone brings in a color chip and wants to "match" the paint color. A computer analysis is done that determines the final color of the paint, factors in the base colors used to produce it and then determines the original formula needed to reproduce the paint chip. To fully use this approach, new satellite systems will be necessary that can more accurately determine both the color and brightness of marine waters, Behrenfeld said. He and colleagues are already working on a satellite concept to do that called ORCA, or Ocean Radiometer for Carbon Assessment.

However, in studies already done, the scientists have demonstrated that carbon-based values are considerably higher in tropical oceans, show greater seasonality at middle and high latitudes, and illustrate important differences in the formation and demise of regional algal blooms. Researchers anticipate a fundamental change in how they can model and observe carbon cycling in the global oceans.

Michael Behrenfeld | EurekAlert!
Further information:
http://www.oregonstate.edu

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

What the world's tiniest 'monster truck' reveals

23.08.2017 | Life Sciences

Treating arthritis with algae

23.08.2017 | Life Sciences

Witnessing turbulent motion in the atmosphere of a distant star

23.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>