Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stanford scientists document fragile land-sea ecological chain

21.05.2012
Douglas McCauley and Paul DeSalles did not set out to discover one of the longest ecological interaction chains ever documented. But that's exactly what they and a team of researchers – all current or former Stanford students and faculty – did in a new study published in Scientific Reports.

Their findings shed light on how human disturbance of the natural world may lead to widespread, yet largely invisible, disruptions of ecological interaction chains. This, in turn, highlights the need to build non-traditional alliances – among marine biologists and foresters, for example – to address whole ecosystems across political boundaries.


The researchers found a link between replacing native trees with non-native palms and the health of the manta ray population off Palmyra Atoll in the Pacific. Credit: Gareth Williams

This past fall, McCauley, a graduate student, and DeSalles, an undergraduate, were in remote Palmyra Atoll in the Pacific tracking manta rays' movements for a predator-prey interaction study. Swimming with the rays and charting their movements with acoustic tags, McCauley and DeSalles noticed the graceful creatures kept returning to certain islands' coastlines. Meanwhile, graduate student Hillary Young was studying palm tree cultivation's effect on native habitats nearby and wondering how the impact on bird communities would play out.

Palmyra is a unique spot on Earth where scientists can compare largely intact ecosystems within shouting distance of recently disturbed habitats. A riot of life – huge grey reef sharks, rays, snapper and barracuda – plies the clear waters while seabirds flock from thousands of miles away to roost in the verdant forests of this tropical idyll.

Over meals and sunset chats at the small research station, McCauley, DeSalles, Young and other scientists discussed their work and traded theories about their observations. "As the frequencies of these different conversations mixed together, the picture of what was actually happening out there took form in front of us," McCauley said.

Through analysis of nitrogen isotopes, animal tracking and field surveys, the researchers showed that replacing native trees with non-native palms led to about five times fewer roosting seabirds (they seemed to dislike palms' simple and easily wind-swayed canopies), which led to fewer bird droppings to fertilize the soil below, fewer nutrients washing into surrounding waters, smaller and fewer plankton in the water and fewer hungry manta rays cruising the coastline.

"This is an incredible cascade," said researcher Rodolfo Dirzo, a senior fellow with the Stanford Woods Institute for the Environment. "As an ecologist, I am worried about the extinction of ecological processes."

Equally important is what the study suggests about these cascades going largely unseen. "Such connections do not leave any trace behind," said researcher Fiorenza Micheli, an associate professor of biology affiliated with the Stanford Woods Institute. "Their loss largely goes unnoticed, limiting our understanding of and ability to protect natural ecosystems." McCauley put it another way: "What we are doing in some ecosystems is akin to popping the hood on a car and disconnecting a few wires and rerouting a few hoses. All the parts are still there – the engine looks largely the same – but it's anyone's guess as to how or if the car will run."

By way of comparison, researcher Robert Dunbar, a Stanford Woods Institute senior fellow, recalled the historical chain effects of increasing demands on water from Central California's rivers. When salmon runs in these rivers slowed from millions of fish each year to a trickle, natural and agricultural land systems lost an important source of marine-derived fertilizer. These lost subsidies from the sea are now replaced by millions of dollars' worth of artificial fertilizer applications. "Humans can really snip one of these chains in half," Dunbar said.

This article was written byRob Jordan, communications writer for the Stanford Woods Institute for the Environment.

Related Information:
Stanford Woods Institute for the Environment
http://woods.stanford.edu/

Rob Jordan | EurekAlert!
Further information:
http://www.stanford.edu

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>