Scientists hope that understanding the mechanisms which determine the diversity and productivity of ecosystems will help ecologists and conservationists to develop strategies to ensure that conservation areas are highly productive and rich in biodiversity.
The study used a lab-based artificial ecosystem of communities of bacteria to examine what happens when the bacteria move around and evolve to live in different parts of the ecosystem over the course of hundreds of generations. The scientists measured the effect this dispersal of species has on the productivity and biodiversity of the ecosystem over all.
'Productive' ecosystems are defined as those that support a large total amount of living matter, from tiny microbes up to plants and animals. Scientists refer to this measurement of the amount of life present as an ecosystem's 'biomass'. A number of studies in the last decade have shown that ecosystems that have a high biodiversity - meaning they are rich in variety of species - are also highly productive over short time scales, but until now the underlying processes creating this link between high levels of biodiversity and productivity over evolutionary time scales have not been understood.
The scientific team behind this new research found that both the biodiversity and productivity of an ecosystem are at a peak when there is an intermediate rate of dispersal of species - not too little and not too much - between different parts of the ecosystem.
When there is little or no dispersal, populations of species that remain in harsh areas of an ecosystem are unable to adapt to their environment due to a low population size and lack of genetic variation. Conversely, when there is too much dispersal in an ecosystem, species evolve to be 'generalists' that can survive in many habitats, but fail to thrive in any given one.
Dr Craig Maclean, one of the authors of the study at the NERC Centre for Population Biology at Imperial College London, explains that an intermediate rate of dispersal creates a 'happy medium' wherein species move around enough to ensure that harsh environments are adapted to, but not so much that they become generalists.
He says: "Dispersal constantly brings new individuals and new genes into harsh environments, which is essential for evolutionary adaptation to difficult environments. When species adapt to new environments it increases the productivity of the ecosystem and it can increase the biodiversity, as movement between different parts of an ecosystem provides more 'niches' for species to exploit."
To carry out the study, the research team created an artificial ecosystem for the bacterium Pseudomonas fluorescens. The ecosystem consisted of 95 different areas, each one containing a different food source. The scientists introduced the bacteria - which could eat approximately half of the 95 food sources - to the ecosystem, and then began to manipulate the rate at which the bacteria dispersed between the 95 different areas.
Every day during the experiment, the team measured the biomass in the ecosystem as an indicator of the ecosystem's productivity, and found that the levels of biomass were highest when there was an intermediate dispersal rate.
After 400 generations, the team isolated bacteria from the ecosystem and measured the ability of the bacteria to grow on each of the food sources. Using this data, the team were able to measure the diversity of the ecosystem, as it indicated how many different species had evolved from the bacteria which were originally introduced to the experiment, which could only eat half of the food sources available.
The research was carried out by an international team, led by Centre National de la Recherche Scientifique scientists at Montpellier 2 University in France, in collaboration with Imperial College London and the University of Liverpool.
Danielle Reeves | alfa
Bioinvasion on the rise
15.02.2017 | Universität Konstanz
Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
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”...
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...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
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...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
20.02.2017 | Materials Sciences
20.02.2017 | Health and Medicine
20.02.2017 | Health and Medicine