Grassland soil microbe communities show seasonal responses, deserve more research
There's more to an ecosystem than the visible plants and animals. The soil underneath is alive with vital microbes. They make sure nutrients from dead plant and animal material are broken down and made useable by other plants. This completes the process of nutrient cycling and carbon storage.
Elizabeth Carlisle reaches into a +Heat plot during plot work in Fall 2010.
Photo credit Danny Walls
Scientists are learning more about how important these microbes are. But how do changes in temperature and precipitation levels affect microbes? And will that affect carbon storage?
A view of the whole experimental layout after initiation of warming and precipitation treatments."These pasture systems are pretty understudied in terms of how climate change will affect them, which is not good because these areas rely so heavily on agriculture," says Lindsey Slaughter of the University of Kentucky. "While this work was part of a longer project studying plant communities, I was able to study soil microbial communities over one year because they are such an important part of these ecosystems."
The project contained four study conditions applied to a Kentucky pasture. One treatment experienced the natural seasonal changes of rainfall and temperature. A second treatment was 3°C warmer than the natural temperature. A third received 30% more precipitation during the growing season. A final group received both extra warming and rainfall treatments.
Slaughter took samples of the soil and its microbes each season. She measured various features of the microbial population. She also looked at how these bacteria and fungi responded to carbon in soil as food.
The experiment revealed some differences associated with warming. Winter soils in the warmed plots had less carbon available for microbial use. These warmed plots also contained 16% more microbes, year-round, compared to those not warmed. However, the most variation occurred because of the seasonal changes in temperature and precipitation, not the experimental changes.
"It was really unexpected because we thought that the experimental conditions would lead to more changes for the soil microbes," explains Slaughter. "We only sampled one year out of the larger five-year study. We can't be sure if the microbes experienced changes initially and just adapted by the time we sampled them, or if their characteristics stayed the same over the whole period. It's an issue of timing that deserves more research."
Reaching into an added heat test plotThe results do not mean these microbes are immune to a changing climate. Slaughter explains the experiment may have reflected short-term stresses the bacteria are able to cope with. For example, the year the study was conducted was a normal year for weather, but in the past the area experienced severe drought.
"If the changes that I saw in one unstressed year, such as the low carbon in the winter in warmed plots, were to persist in the next couple of years, that could have long term effects on the microbes and even the plants," Slaughter says. "We found big differences in plant communities due to the different treatments, even though we saw little difference in soil microbial communities."
She adds that more severe, long-term stresses from a changing climate could cause negative effects. The role of soil microbes in storing carbon dioxide is important to consider in climate change models because they can have such a large impact.
"It's hard to make generalizations about how areas will react to the effects of climate change. Different regions will experience different changes," says Slaughter. "Our results show that for this year-long period, seasonal changes had more of an effect than making the soils warmer and wetter. But the small changes we did see definitely point to the need for a long-term study here and in other locations."
Soil Science Society of America Journal published the research, funded by the U.S. Department of Energy and National Science Foundation.
Susan Fisk | EurekAlert!
Filling the gap: High-latitude volcanic eruptions also have global impact
20.11.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences
Antarctic landscape insights keep ice loss forecasts on the radar
20.11.2017 | University of Edinburgh
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...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Physics and Astronomy
21.11.2017 | Life Sciences