Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ants plant tomorrow's rainforest

18.03.2014

Tropical montane rain forests are highly threatened and their remnants are often surrounded by deforested landscapes.

For the regeneration of these degraded areas, seed dispersal of forest trees plays a crucial role but is still poorly understood. Most tree species are dispersed by birds and mammals, but also by ants.


Ants are attracted by the lipid-rich aril of Clusia seeds and move the seeds to safe microsites for germination. Picture: S. Gallegos

A study published today in the Journal of Ecology by a team from the LOEWE Biodiversity and Climate Research Centre and the University of Halle-Wittenberg proves the importance of this hitherto neglected ecosystem function for the restoration of montane rain forests. Ants promote the regeneration of these forests by dispersing seeds to safe sites for tree establishment.

The Yungas, a region on the eastern slopes of the Bolivian Andes near La Paz, are marked by elongated valleys with relicts of the original mountain rain forest. Due to land-use practices like slash-and-burn agriculture and the extension of coca plantations, the forests are highly fragmented. The forest relicts are surrounded by an open, largely degraded cultural landscape.

In this context, the team conducted experiments to find out to what extent ants contribute to the dispersal of a widespread, primarily bird-dispersed tree (Clusia trochiformis) and tested whether this ecosystem function may contribute to the restoration of deforested areas.
The red, lipid-rich aril, a fleshy pulp surrounding the seeds of Clusia, is highly attractive to many animals. Birds are the primary dispersers.

They feed on the nutritious part of the fruits, the fleshy aril, and defecate the seeds. Ants haul seeds, which have fallen to the ground, to their nests or leave them intact on their way. Research has already been conducted on the influence of this so-called secondary seed dispersal, but very little is known about its impact in degraded forest ecosystems. The study reveals that ants reduce seed predation by rodents and increase germination success – which confirms the importance of this ecosystem function for forest regeneration.

The study has been carried out in two 3,000 ha islands of natural mountain rain forest, which are surrounded by coca fields and degraded fallows, covered with fern and shrub vegetation. The microclimate in the deforested areas is characterized by harsh abiotic conditions that limit seed germination and recruitment, and hence inhibit the re-establishment of forest trees. The researchers deposited 1,440 Clusia seeds in 72 depots at six sites. At each site, they studied three habitat types: forest interior, degraded habitat close to the forest and degraded habitat far from the forest edge.

To quantify the effect of rodents in addition to the impact of ants, half of the depots where equipped with wire exclusion cages.

Well-concealed: ants reduce predation and increase germination

"Ants readily approached and hauled away about 60 percent of all seeds," says Silvia Gallegos, lead author of the study and a doctoral student at the Biodiversity and Climate Research Centre (BiK-F) and the University of Halle-Wittenberg. 48 hours and again one month after establishing the depots, the team searched for the seeds within a 2.5 meter radius. More than 80 percent of the seeds transported away could be relocated. In most cases, the ants removed the aril, which is a benefit for the plants, due to a lower risk of fungal infestation and a higher germination rate.

But there are more positive effects of ants: "Especially in the degraded habitats, we found that seeds which had been removed by ants were predated less often and germinated more frequently than the unmoved seeds," explains Dr. Matthias Schleuning, co-author and scientist at BiK-F. Quite often, the ants removed the seed aril only in their nests or on the way there – often leaving the seeds protected by the litter layer.

Under the leaf litter, the seeds were less likely to be detected by rodents or other seed predators and benefited from the humid conditions, favorable for germination. The effect in the deforested habitats was clearly visible: one month after the experiment had started, establishment of seedlings was about five times higher for dispersed than for non-dispersed seeds. Dispersal distance had a positive effect as well: The farther the ants had transported the seeds, the higher was the chance that Clusia seedlings had established.

Even more important services by ants in the future

Ants have a clearly positive impact on the dispersal and establishment of the investigated tree species. This is particularly relevant as other animal and plant species may follow the species that facilitates the establishment of others. "We may use our knowledge to stimulate the establishment of Clusia in degraded habitats and enhance the regeneration of deforested areas" says Silvia Gallegos. Due to the ecosystem service provided by ants in the degraded areas, a faster and sustainable establishment of tree seedlings like Clusia may be expected.

In the medium term, this will enhance living conditions for a number of other animal and plant species and accelerate the regeneration of the mountain rain forest ecosystem. Schleuning concludes: “Drought frequencies in the Andes are likely to increase in the future. Under this scenario, the dispersal function of ants may further increase in importance for the restoration of tropical mountain forests.”

Publication:
Gallegos, S. C., Hensen, I., & M. Schleuning: Secondary dispersal by ants pro-motes forest regeneration after deforestation. - Journal of Ecology, DOI 10.1111/1365-2745.12226

For further information please contact:
Dr. Matthias Schleuning
LOEWE Biodiversity and Climate Research Centre (BiK-F)
Tel. +49 (0)69 7542 1892
Matthias.Schleuning@senckenberg.de

Silvia Gallegos
LOEWE Biodiversity and Climate Research Centre (BiK-F)
Tel. +49 (0)69 7542 1887
silvia.gallegos@senckenberg.de

or

Dr. Julia Krohmer
LOEWE Biodiversity and Climate Research Centre (BiK-F),
Transfer office
Tel. +49 (0)69 7542 1837
julia.krohmer@senckenberg.de

Sabine Wendler | Senckenberg
Further information:
http://www.senckenberg.de

Further reports about: BiK-F Biodiversity Climate Senckenberg ants dispersal ecosystem effect forests germination habitat seeds species

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | 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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>