Germinating quickly, growing fast, withstanding competitors and defending against herbivores - already since decades, ecologists have suggested that these are important characteristics of successful plants.
In greenhouse experiments, the characteristics of the different plant species are closely examined.
Anne Kempel, Institute of Plant Sciences, University of Bern.
However, it has also been suggested that species characteristics are less important as determinants of plant establishment success than other factors such as seed availability or environmental characteristics, like dense vegetation.
In Bern, researchers of the Institute of Plant Sciences and the University of Konstanz carefully examined the importance of those species characteristics, and provide evidence that they affect – more strongly than has been anticipated – success or failure of species.
Field and greenhouse experiments combined
Some unique features of the Bernese study are the high number of used plant species and the sophisticated combination of several independent experiments. In a comprehensive field experiment, the scientists sowed more than 90 different native and exotic plant species into 16 grasslands with different vegetation densities in the Canton of Bern.
They varied the introduced seed number and manipulated soil disturbance. Then, they observed carefully which of the sown plant species established in the field. At the same time, the scientists conducted several greenhouse experiments to assess, as accurately as possible, the characteristics of each species – from seed mass and germination rate to the speed of growth, the competitive ability and the resistance against herbivores, like caterpillars.
«Although it is known that herbivory and competition are relevant for plant establishment, the response of many plants to those factors is rarely measured due to the large amount of work», comments Markus Fischer, professor of plant ecology at the University of Bern. By combining the results from the field and the greenhouse, the most important species traits and environmental characteristics for establishment success could be identified.
The winners are well defended against herbivores
The Bernese plant scientists could show that at the beginning of the experiment mainly species with a high seed mass germinated in the grasslands. In addition, a high number of seeds sown increased early establishment success. However, the importance of factors changed during the course of the study.
«Interestingly, at the end, mainly traits related to interactions between plants and plants or plants and animals were important», reports Anne Kempel, first author of the study. Accordingly, plants that were well defended against voracious insects were the most successful ones in the long run.
«Our results are in line with general theories on community assembly and invasion success», explains Mark van Kleunen, the leader of the project. First, the non-living environment, the so called «abiotic filter», constrains establishment of species without certain physiological adaptations.
The germinated species then have to pass the so-called «biotic filter» - which means that they have to withstand herbivores, pathogens and competitors to persist in a community. «Our study shows that this second filter is of major importance, and is even gaining in importance with time» says van Kleunen.
The study, now published in «Proceedings of the National Acadamy of Sciences» helps to better understand the assembly of plant communities. According to the researchers the results can also contribute to the early detection of potentially new invasive species – for instance when plant species introduced for horticultural purposes, prior to accreditation, are tested for their traits. «With such a screening, future plant invasions may eventually be prevented in Switzerland», says Kempel.Information on the publication:
Nathalie Matter | Universität Bern
Ambush in a petri dish
24.11.2017 | Friedrich-Schiller-Universität Jena
Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology
High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons
The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
24.11.2017 | Physics and Astronomy
24.11.2017 | Health and Medicine
24.11.2017 | Earth Sciences