Research spanning 6 continents sheds light on important interactions among nutrients, grazers, and plants
Two wrongs may not make a right. But when it comes to grassland plant species diversity, it just might. Two impacts often controlled by humans — being fertilized and being eaten — can combine to the benefit of biodiversity, according to an innovative international study led by U of M researchers Elizabeth Borer and Eric Seabloom.
The findings, published March 9 in the online edition of Nature in advance of print publication, are important in a world where humans are changing both herbivore distribution and the supply of nutrients like nitrogen or phosphorus, and where understanding the interplay among nutrients, herbivores and plant growth is critical to our capacity to feed a growing human population and protect threatened species and ecosystems.
To conduct the study, Borer and Seabloom enlisted the help of the Nutrient Network, or NutNet, a collaborative international experiment they and a few colleagues founded in 2005 as a resource for understanding how grasslands around the world will respond to a changing environment. NutNet scientists at 40 sites on six continents set up research plots with and without added fertilizer and with and without fences to keep out the local herbivores such as deer, kangaroos, sheep or zebras. Every year since then, they have measured the amount of plant material grown, light reaching the ground, and number of species of plants growing in the plots.
When the researchers compared data across the 40 study sites, they found that fertilizing reduced the number of plant species in the plots as species less able to tolerate a lack of light were literally overshadowed by fast-growing neighbors. On both fertilized and unfertilized plots, where removal of vegetation by herbivores increased the amount of light that struck the ground, plant species diversity increased. And these results held true whether the grassland was in Minnesota, Argentina or China, and whether the herbivores involved were rabbits, sheep, elephants or something else.
"Biodiversity benefits humans and the environments that sustain us. Understanding how human actions control biodiversity is important for maintaining a healthy environment," says Borer. "What this suggests is that these two impacts, which are ubiquitous globally, dovetail with changes in light availability at the ground level, and that appears to be a big factor in maintaining or losing biodiversity in grasslands. In short, where we see a change in light, we see a change in diversity."
The findings add a key piece to the puzzle of how human impacts affect prairies, savannas, alpine meadows and other grasslands. Biodiversity plays an important role in how resilient communities of plants and animals are in the face of change. By showing how fertilization, grazing, and biodiversity are linked, the research moves us one step closer to understanding what we can do to help keep grassland ecosystems and all of the services they provide healthy and thriving in a changing world.
"Global patterns of biodiversity have largely defied explanation due to many interacting, local driving forces," says Henry Gholz, program director in the National Science Foundation's (NSF) Division of Environmental Biology, which funded the coordination of this research. "These results show that grassland biodiversity is likely largely determined by the offsetting influences of nutrition and grazing on light capture by plants."
Yann Hautier, a Marie Curie Fellow associated with both the Department of Ecology, Evolution, and Behavior at the University of Minnesota and the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich and U of M research scientist Eric Lind were co-authors of the study along with researchers from universities and government agencies around the world.
Stephanie Xenos | EurekAlert!
Cereals use chemical defenses in a multifunctional manner against different herbivores
06.12.2018 | Max-Planck-Institut für chemische Ökologie
Can rice filter water from ag fields?
05.12.2018 | American Society of Agronomy
An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.
In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....
Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.
The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...
For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.
The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...
Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens
Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...
Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light
When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...
11.02.2019 | Event News
30.01.2019 | Event News
16.01.2019 | Event News
22.02.2019 | Physics and Astronomy
22.02.2019 | Materials Sciences
22.02.2019 | Life Sciences