The continued growth of cropland and loss of natural habitat have increasingly simplified agricultural landscapes in the Midwest.
In a study supported in part by the National Science Foundation's (NSF) Kellogg Biological Station Long-Term Ecological Research (LTER) site in Michigan--one of 26 such NSF LTER sites around the world--scientists concluded that this simplification is associated with increased crop pest abundance and insecticide use.
"This research suggests that there are simple ecological solutions--such as preservation or restoration of semi-natural lands within large agricultural regions--that could reduce the need for insecticides and contribute to agricultural economies," says Nancy Huntly, NSF program director for the network of LTER sites.
While the relationship between landscape simplification, crop pest pressure and insecticide use has been suggested before, it has not been well supported by empirical evidence, scientists say.
Results of the study, published in this week's issue of the journal Proceedings of the National Academy of Sciences, are the first to document a link between simplification and increased insecticide use.
"When you replace natural habitat with cropland, you tend to get more crop pest problems," says lead author Tim Meehan, an entomologist at the University of Wisconsin-Madison (UW-Madison).
He and other authors are affiliated with the Great Lakes Bioenergy Research Center, one of three U.S. Department of Energy Bioenergy Research Centers, and with NSF's Kellogg Biological Station LTER site.
"Two things drive this pattern," says Meehan. "As you remove natural habitats, you remove habitat for beneficial predatory insects, and when you create more cropland you make a bigger target for pests--giving them what they need to survive and multiply."
Because landscape simplification has long been assumed to increase pest pressure, Meehan and colleagues were not surprised to find that counties with less natural habitat had higher rates of insecticide use.
One striking finding was that landscape simplification was associated with annual insecticide application to an additional 5,400 square miles--an area the size of Connecticut.
Although simplification of agricultural landscapes is likely to continue, the research suggests that the planting of perennial bioenergy crops--like switchgrass and mixed prairie--can offset some negative effects.
"Perennial crops provide year-round habitat for beneficial insects, birds, and other wildlife, and are critical for buffering streams and rivers from soil erosion and preventing nutrient and pesticide pollution," says Doug Landis, a Michigan State University entomologist and landscape ecologist who's affiliated with the Kellogg Biological Station LTER site.
Perennial grasslands that can be used for bioenergy could also provide biodiversity support, especially beneficial insect support, says Claudio Gratton, a UW-Madison entomologist.
"If we can create agricultural landscapes with increased crop diversity, then perhaps we can increase beneficial insects, reduce pest pressure and reduce the need for chemical inputs into the environment," Gratton says.
"We are at a junction right now," he believes.
"There is increased demand for renewable energy, and one big question is: where it will come from? We hope that these kinds of studies will help us forecast the impacts that bioenergy crops may have on agricultural landscapes."Media Contacts
Cheryl Dybas | EurekAlert!
Filling intercropping info gap
16.11.2017 | American Society of Agronomy
Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University
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,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
17.11.2017 | Physics and Astronomy
17.11.2017 | Health and Medicine
17.11.2017 | Studies and Analyses