Rapid Effects of Climate Change On Plants and their EcosystemsAn international team of researchers led by two Villanova University biologists has found that climate change is dramatically altering terrestrial plant communities and their ecosystems at such a rapid pace that having a stable baseline from which to conduct experiments is becoming increasingly difficult.... For most species (57 per cent), according to the article, the magnitude of ambient change was greater than the magnitude of treatment effects—the opposite of the result expected by the researchers."A preponderance of evidence suggests that ongoing climate change is dramatically altering terrestrial plant communities," the article states.
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One key take-away from the IPCC report that supports our findings is that changes across many ecosystems may be happening faster than we thought," Chapman agreed.
"Plants are shifting under our feet as we're trying to predict the future.""Plants are the base of the food web and drive the carbon cycle, nutrient cycles and water cycles on which we rely," Langley said. "When the plant species change, everything else in the ecosystem may follow."
He added,
"We are trying to simulate how the future earth will look with global change, but, climate change and nutrient pollution are changing ecosystems so fast it's tough to experiment on top of those changes. In the face of ongoing environmental change, our experiments may be like 'rearranging deck chairs on the Titanic'.Open Access: J.A.Langley, et. al.,
Ambient changes exceed treatment effects on plant species abundance in global change experiments.
Global Change Biology. 18 October 2018
https://doi.org/10.1111/gcb.14442 -----------------------------------------------
Study Finds Availability of Nitrogen to Plants is Declining as Climate WarmsResearchers have found that global changes, including warming temperatures and increased levels of carbon dioxide in the atmosphere, are causing a decrease in the availability of a key nutrient for terrestrial plants. This could affect the ability of forests to absorb carbon dioxide from the atmosphere and reduce the amount of nutrients available for the creatures that eat them.... "This idea that the world is awash in nitrogen and that nitrogen pollution is causing all these environmental effects has been the focus of conversations in the scientific literature and popular press for decades," said Elmore. "What we're finding is that it has hidden this long-term trend in unamended systems that is caused by rising carbon dioxide and longer growing seasons."
Researchers studied a database of leaf chemistry of hundreds of species that had been collected from around the world from 1980-2017 and found a global trend in decreasing nitrogen availability. They found that most terrestrial ecosystems, such as forests and land that has not been treated with fertilizers, are becoming more oligotrophic, meaning too little nutrients are available.
"If nitrogen is less available it has the potential to decrease the productivity of the forest. We call that oligotrophication," said Elmore. "In the forested watershed, it's not a word used a lot for terrestrial systems, but it indicates the direction things are going."
"This new study adds to a growing body of knowledge that forests will not be able to sequester as much carbon from the atmospheric as many models predict because forest growth is limited by nitrogen," said Eric Davidson, director of the University of Maryland Center for Environmental Science's Appalachian Laboratory. "These new insights using novel isotopic analyses provide a new line of evidence that decreases in carbon emissions are urgently needed."
Joseph M. Craine et al.
Isotopic evidence for oligotrophication of terrestrial ecosystems,
Nature Ecology & Evolution (2018).
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Scientists Warn of Insect Pest Outbreaks and Reduced Wheat YieldsClimate-warming affects farmlands by increasing pests but not their natural predators, resulting in reduced crop yields, new research has revealed.The study, published today in the journal,
Molecular Ecology, provides the first experimental evidence of how the interactions between agricultural plants, greenflies and tiny parasitoid wasps are affected in a world where temperatures are increased by 1.4°C.
Scientists at Newcastle University and the University of Hull have also shown that a rise in temperature drives changes in the crop, altering the growing patterns of the wheat that produced fewer, lighter seeds.
Stephane A.P. Derocles et al.
Climate-warming alters the structure of farmland tri-trophic ecological networks and reduces crop yield,
Molecular Ecology (2018).
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Non-Native Plants in Homeowners' Yards Endanger Wildlife"Most homeowners think plants are just decorations with no thought to the ecological roles plants must play in our landscapes," Tallamy said. "So they go to the nursery and buy the prettiest plant they can find. The nursery industry has pushed plants from someplace else for a century because they are unusual and have market value."
Most plant-eating insects can only eat species with which they have coevolved. Non-native plants have defensive chemicals in their tissues, which ward off indigenous insects. The indigenous insects cannot eat a given plant unless it has developed the adaptations to circumvent those defenses. Not only do non-native plants smell and taste different, but these species are often toxic to most of native bugs.