Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Marsh plants actively engineer their landscape

14.02.2013
Marsh plants, far from being passive wallflowers, are "secret gardeners" that actively engineer their landscape to increase their species' odds of survival, says a team of scientists from Duke University and the University of Padova in Italy.

Scientists have long believed that the distribution of plants within a marsh is a passive adaption in which species grow at different elevations because that's where conditions like soil aeration and salinity best meet their needs.

But this team found intertidal marsh plants in Italy's famed Venetian lagoon were able to subtly tune, or adjust, their elevations by producing different amounts of organic soil, and trapping and accumulating different amounts of inorganic sediments as part of a complex interplay with the environment.

"Our study identifies the visible signature of a two-way feedback occurring between the vegetation and the landscape," said Marco Marani, professor of ecohydrology at Duke's Nicholas School of the Environment and Pratt School of Engineering. "Each species builds up the elevation of its substrate to within a favorable range for its survival, much the way corals in the animal kingdom do."

The finding may help scientists better predict marsh ecosystems' resilience to climatic changes such as sea level rise.

"Obviously, this is not a conscious choice on the part of the plants," Marani said. "It's a natural mechanism -- how marshes work. We just didn't understand it in such detail until now."

The study appears this week in the early online edition of the Proceedings of the National Academy of Sciences.

The team used numerical modeling to visualize the dynamic interactions of marsh ecosystems over time, and tested the models against detailed topographical surveys of elevations and distributions of plant species in the Venetian lagoon.

"We've been studying this same marsh for 15 years and, as in similar studies around the world, we were using GPS technology with an accuracy of plus or minus one centimeter in elevation," Marani explained. For the new study, they used a more precise surveying instrument, an electronic theodolite, which measure elevations accurately to within less than one millimeter. "It allowed us to observe differences so subtle that they went unnoticed before," he said.

The differences in substrate-building capabilities between species are often minute, but they allow each species to stabilize the soil within different stable states, or layers, in the marsh. Some species prefer elevations at or below mean sea level; others prefer higher elevations that are less often inundated.

"Interestingly, our models and surveys show that plants make trade-offs when colonizing within their preferential ranges," Marani said. "Entire sections of a species' vegetation patch often are located above the elevation needed for its maximum biomass productivity." This gives it a bit of margin to compensate for external fluctuations, such as the rates of relative sea level rise or sediment availability.

"Essentially," he said, "the species hedges its bet by trading maximum productivity for greater long-term stability."

Scientists have long known that biodiversity plays an important role in a marsh ecosystem's long-term health and survival, "but this paper provides a clear causal link suggesting how and why," he said. "The take-home message is that the more species you have colonizing different levels within a marsh, the more resilient to abrupt change the marsh as a whole will be."

He said that marshes in which an invasive species, such as cordgrass, has pushed out other species will be less resilient to climatic changes.

Marani's co-authors on the new study are Cristina Da Lio and Andrea D'Alpaos of the University of Padova, Italy.

CITATION: "Vegetation engineers marsh morphology through multiple competing stable states," Marco Marani, Cristina Da Lio and Andrea D'Alpaos. Published week of Feb. 11, 2013 in the early online edition of the Proceedings of the National Academy of Sciences. DOI - 10.1073/pnas.1218327110

Tim Lucas | EurekAlert!
Further information:
http://www.duke.edu

More articles from Ecology, The Environment and Conservation:

nachricht Northern bald ibises fit for their journey to Tuscany
21.08.2015 | Veterinärmedizinische Universität Wien

nachricht Boreal forests challenged by global change
21.08.2015 | International Institute for Applied Systems Analysis (IIASA)

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: Elektrofahrzeuge kabellos laden und entladen

Über ein kabelloses Ladesystem können Elektroautos künftig nicht nur tanken, sondern die Energie ins Stromnetz zurückspeisen. Auf diese Weise helfen sie das Netz zu stabilisieren. Das kostengünstige Ladesystem erreicht hohe Wirkungsgrade – über den vollen Leistungsbereich von 400 Watt bis 3,6 Kilowatt. Die Abstände zwischen Auto und Ladespule können bis zu 20 Zentimeter be- tragen. Auf der Internationalen Automobil Ausstellung IAA in Frankfurt stellen Fraunhofer-Forscher den Prototyp vom 15. bis 18. September 2015 vor (Halle 4, Stand D33).

Es regnet in Strömen. Wer jetzt ein dickes unhandliches Kabel zwischen Elektrofahrzeug und Ladesäule einstecken muss, wird patschnass. Doch es nützt nichts,...

Im Focus: Increasingly severe disturbances weaken world's temperate forests

Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.

"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...

Im Focus: Meeresinseln als Heimat einmaliger Pflanzenarten

Warum leben in manchen Ökosystemen auffallend viele, in anderen Ökosystemen nur wenige Pflanzenarten? Wie kommt es, dass einige Arten jeweils nur in einer bestimmten, klar abgrenzbaren Region der Erde zuhause sind? Mit diesen Fragen hat sich Dr. Manuel Steinbauer in einer Reihe wissenschaftlicher Studien an der Universität Bayreuth befasst. Für seine Forschungsarbeiten wird der Bayreuther Ökologe, der zurzeit als Postdoc an der dänischen Universität Aarhus forscht, mit dem diesjährigen Wilhelm Pfeffer-Preis der Deutschen Botanischen Gesellschaft (DBG) ausgezeichnet. Der Preis ist mit 2.500 Euro dotiert.

Wenn es darum geht, den Gründen für die Verbreitung pflanzlicher Arten auf die Spur zu kommen und theoretische Erklärungsansätze zu überprüfen, sind...

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: Optische Schalter - Lernen mit Licht

Einem deutsch-französischen Team ist es gelungen, einen lichtempfindlichen Schalter für Nervenzellen zu entwickeln. Dies ermöglicht neue Einblicke in die Funktionsweise von Gedächtnis und Lernen, aber auch in die Entstehung von Krankheiten.

Lernen ist nur möglich, weil die Verknüpfungen zwischen den Nervenzellen im Gehirn fortwährend umgebaut werden: Je häufiger bestimmte Reizübertragungswege...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Frankfurter Hochhausfassadentage 2015: Frankfurt UAS veranstaltet Symposium und Hochhausführung

31.08.2015 | Veranstaltungen

Erreger unter Superlupen – Aufbruch in unsichtbare Welten

31.08.2015 | Veranstaltungen

Fehlermeldungen des Gehirns auf der Spur

31.08.2015 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Fehlgeleitete Galileo-Satelliten für Forschungsmission freigegeben

31.08.2015 | Geowissenschaften

Frankfurter Hochhausfassadentage 2015: Frankfurt UAS veranstaltet Symposium und Hochhausführung

31.08.2015 | Veranstaltungsnachrichten

Siemens-Lösungen unterstützen Diagnose und Therapie kardiovaskulärer Erkrankungen

31.08.2015 | Messenachrichten