Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

If we are what we eat, some lake fish are made of maple leaves

15.01.2004


Study shown fallen leaves play a role in the food web



Aquatic plants form the base of the food web. The energy they create supports aquatic life, from invertebrates to the largest sport fish. Now, a study shows that aquatic plants are receiving a little help from trees. In a paper in this week’s issue of the journal Nature, Michael Pace and Jonathan Cole of the Institute of Ecosystem Studies in Millbrook, New York, along with colleagues from Wisconsin and Sweden, indicate that a significant part of the aquatic food chain is supported by terrestrial organic matter that originates on shore.

A building block of life, organic carbon is essential to aquatic food webs. In lakes, aquatic plants produce organic carbon by harnessing the sun’s energy (photosynthesis); some of this carbon supports the growth of fish and invertebrate populations. Scientists have long suspected that organic carbon from land is also significant to aquatic life, but the idea is difficult to demonstrate.


By tracing the fate of carbon through large-scale lake manipulations, Pace, Cole, and their colleagues have revealed that in some waters terrestrial organic carbon significantly subsidizes the aquatic food web.

"These scientists have found an ingenious method of teasing apart the carbon cycle of lakes," says James Morris, program director in the National Science Foundation (NSF)’s division of environmental biology, which funded the research. "Their study reveals a surprising degree of dependence of lake food webs on sources of organic matter transported into the lakes from the surrounding watershed. These findings reinforce the concept that the ecology of lake ecosystems is tightly coupled with that of the surrounding terrestrial landscape."

That maple tree leaves many eventually become perch, and that the vegetation around a water body can have profound impacts on the animal life within the body of water blur the perceived ecological boundaries between aquatic and terrestrial systems.

The impetus behind the study, which involved manipulating two Michigan lakes, was to better understand the aquatic food chain. Pace explains, "We wanted to reveal what many ecologists have long thought- aquatic life is partly dependent on organic matter produced in the watershed." Using a chemical tracer, Pace and his colleagues set out to quantify this assumption. "The moral of the story," Pace comments, "is, yes, fish are made from algae, but fish are also partly made from maple leaves."

In Lakes Peter and Paul located at the University of Notre Dame Research Center, the scientists tested whether lake plant production was sufficient to support resident aquatic life.

They found that 40-55 percent of particulate carbon and 2250 percent of zooplankton (small animals that live in the water column) in the lakes are derived from terrestrial sources, which confirms that terrestrial carbon fuels aquatic production. The carbon in the zooplankton reflects their dependence on both lake plant production and terrestrial organic matter. Zooplankton are a dietary staple of many fish, especially in very young life stages.

"Our results," notes Cole, "tell us there is not nearly enough aquatic carbon to support these animals. They are dependent on terrestrial inputs."

Pace comments, "We now have direct experimental evidence that confirms that aquatic food chains are supported not just by the production of plants in the water but also by the production of plants on the land surrounding lakes and ponds. The leaves and organic matter that enter lakes are ultimately incorporated into aquatic animals." These findings challenge traditional views of the aquatic food web and may help watershed managers. "Organic matter from the watershed subsidizes lake food webs, allowing more animal life in the lakes than if they were simply isolated water bodies," Pace concludes.


###
NSF program contact: James Morris, jmorris@nsf.gov.
Media contact: Cheryl Dybas, 703-292-7734, cdybas@nsf.gov.

Cheryl Dybas | NSF
Further information:
http://www.nsf.gov
http://www.nsf.gov/home/news.html

More articles from Ecology, The Environment and Conservation:

nachricht Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>