Researchers, pictured collecting core samples in St. Paul, Alaska, compared pollen grains from core and mire samples in order to determine the historical effects of climate change on vegetation. Photo by Jack Williams
May 20 (UPI) -- Climate change is rapidly altering the planet's vegetation. In fact, new research -- published Thursday in the journal Science -- suggests Earth's vegetation is changing faster today than it has in the last 18,000 years.
Over the last few decades, hundreds of studies have looked at the effects of climate change on various ecosystems
Climate scientists, ecologists and others have worked together to gauge the influence of rising temperatures and shifting weather patterns on greening in the Arctic and forest composition in the Amazon.
Few studies, however, have examined the effects of climate change on vegetation with as a broad lens as the new one, according to the researchers.
For the latest study, researchers used ancient pollen grains to quantify the pace at which Earth's global plant communities have changed through the millennia.
"We analyzed a network of over 1,000 fossil pollen records worldwide -- the largest such analysis to date," study co-author Jack Williams, a researcher and professor of geography at the University of Wisconsin, told UPI in an email.
"These fossil pollen records are retrieved from sediment cores taken from lakes and mires, and they provide continual records of vegetation history going back thousands of years," said Williams, a professor at the University of Wisconsin.
Scientists can identify the plant groups from which different fossilized pollen grains originated.
By surveying the distribution of different types of pollen grains across a variety of excavation sites, researchers can quantify changes in plant abundances and distributions over space and time.
"For this paper, we calculated a rate-of-change metric that is calculated for each site individually, then averaged across sites in a region," Williams said. "This metric basically sums up all the changes in abundance for individual taxa, and so is an index of community-level -- or ecosystem-level -- change."
Pollen grains from the uppermost sediment layers of cores sourced from lake beds around the world showed the pace of vegetation change has been accelerating over the last 3,000 years.
The data suggests modern plant communities are changing faster than they were 18,000 years ago at the end of the last ice age, as plants colonized newly thawed territory.
In addition to confirming the disruptive effects of human-caused climate change, the latest research suggests -- as several other studies have shown -- humans have been altering the planet's ecosystems for a few thousand years.
"I was definitely surprised that the acceleration in rates of vegetation change between 3,000 and 4,000 years ago was detectable on all continents, despite very different histories in land use and climate change," Williams said.
"This needs further exploration, but is definitely contributes to an exciting new wave of research looking at how ecosystems were affected by early human societies worldwide," he said.
In followup studies, scientists said they hope to determine whether changes in land-use patterns by early human societies might explain the dramatic shifts that began between 3,000 and 4,000 years ago.
"We are also particularly interested in looking at the climatic and human drivers of vegetation changes in the tropics, given the importance of these ecosystems for storing carbon and protecting biodiversity," Williams said.
Humans significantly altered biodiversity on islands, study shows
A research team on Tenerife takes sediment cores containing pollen, which revealed the effects of more recent human colonization of the island. Photo by José María Fernández Palacios/University of Bayreuth
April 30 (UPI) -- An international team of researchers found that humans have significantly altered biodiversity on colonized islands in the past 1,500 years, according to a study published Friday in the journal Science.
By analyzing 27 fossil pollen sequences encompassing 5,000 years from islands across the world, scientists quantified the rates of change in vegetation composition before and after human arrival.
According to the analysis, there were faster rates of turnover on islands colonized in the past 1,500 years than for those colonized earlier.
Professor Dr. Manuel Steinbauer of the University of Bayreuth and Dr. Sandra Naogue of the University of Southampton extracted, dated and identified pollen from wind-pollinated plants deposited in the sediment of lakes and bogs.
The islands chosen for the study were never connected to the mainland, researchers said.
"For each of the 27 islands, our study shows how vegetation composition has changed over the last 5,000 years. Humans' colonization of the previously undisturbed islands falls within this period. We can therefore trace how natural systems change as a result of human arrival," said study co-author Steinbauer.
"This transformation from a natural to a human-dominated system can only be observed on islands. On continents, humans have been extensively changing ecological systems for a very long time. What a natural ecosystem would look like here, we can often no longer tell," Steinbauer said.
On 24 of the 27 islands studied, the arrival of humans marked a significant change in vegetation, especially on islands colonized in the past 1,500 years.
For those colonized earlier, the turnover was less pronounced.
The researchers attribute this difference with an increase in agricultural technology and its associated effects on biodiversity.
"The results of the study highlight the extensive changes we humans are causing in ecological systems. The change in pollen composition in our study mainly reflects human land use over millennia," Steinbauer said.
"With the beginning of the industrial age, human-induced transformation of ecological systems has accelerated even further. Adding to this, ecological systems are now additionally affected by human-induced climate change," he said.
A research team on Tenerife takes sediment cores containing pollen, which revealed the effects of more recent human colonization of the island. Photo by José María Fernández Palacios/University of Bayreuth
April 30 (UPI) -- An international team of researchers found that humans have significantly altered biodiversity on colonized islands in the past 1,500 years, according to a study published Friday in the journal Science.
By analyzing 27 fossil pollen sequences encompassing 5,000 years from islands across the world, scientists quantified the rates of change in vegetation composition before and after human arrival.
According to the analysis, there were faster rates of turnover on islands colonized in the past 1,500 years than for those colonized earlier.
Professor Dr. Manuel Steinbauer of the University of Bayreuth and Dr. Sandra Naogue of the University of Southampton extracted, dated and identified pollen from wind-pollinated plants deposited in the sediment of lakes and bogs.
The islands chosen for the study were never connected to the mainland, researchers said.
"For each of the 27 islands, our study shows how vegetation composition has changed over the last 5,000 years. Humans' colonization of the previously undisturbed islands falls within this period. We can therefore trace how natural systems change as a result of human arrival," said study co-author Steinbauer.
"This transformation from a natural to a human-dominated system can only be observed on islands. On continents, humans have been extensively changing ecological systems for a very long time. What a natural ecosystem would look like here, we can often no longer tell," Steinbauer said.
On 24 of the 27 islands studied, the arrival of humans marked a significant change in vegetation, especially on islands colonized in the past 1,500 years.
For those colonized earlier, the turnover was less pronounced.
The researchers attribute this difference with an increase in agricultural technology and its associated effects on biodiversity.
"The results of the study highlight the extensive changes we humans are causing in ecological systems. The change in pollen composition in our study mainly reflects human land use over millennia," Steinbauer said.
"With the beginning of the industrial age, human-induced transformation of ecological systems has accelerated even further. Adding to this, ecological systems are now additionally affected by human-induced climate change," he said.
Wildlife biodiversity is a boon
RELATED Land use changes could increase risk of disease outbreaks
These types of animals tend do well -- or at least better than others -- in degraded ecosystems, which may explain why researchers found animals credited with the spread of zoonotic diseases were less likely to be species of conservation concern.
"When we erode biodiversity, we favor species that are more likely to be zoonotic hosts, increasing our risk of spillover events," Ostfeld said. "Managing this risk will require a better understanding of how things like habitat conversion, climate change and over-harvesting affect zoonotic hosts -- and how restoring biodiversity to degraded areas might reduce their abundance."
Researchers suggest efforts to prevent -- as well as to predict and prepare for -- the next spillover event should focus less on particular species and more on groups of animals and the habitats where they are mostly likely to congregate.
"Restoration of biodiversity is an important frontier in the management of zoonotic disease risk. Those pathogens that do spill over to infect humans -- zoonotic pathogens -- often proliferate as a result of human impacts," Keesing said. "As we rebuild our communities after COVID-19, we need to have firmly in mind that one of our best strategies to prevent future pandemics is to protect, preserve, and restore biodiversity."
In a separate study, published Monday in the journal PNAS, researchers at Yale University looked at the effects of biodiversity on seafood nutrition.
The Yale analysis showed seafood sourced from biodiverse ecosystems features higher levels of nutrients -- including vitamins, minerals and fatty acids -- than seafood from areas of the ocean that have been degraded by overfishing, pollution and climate change.
"What we found is that biodiversity is crucial to human health," co-author Joey Bernhardt, an ecologist and postdoctoral fellow at Yale, said in a press release.
Though there is much scientists still don't understand about COVID-19, a mounting body of research suggests diet is intimately linked with the body's immune system.
The latest research suggests even calories from the same types of food aren't always equal, and the findings could have significant implications for coastal communities that consume lots of seafood.
For the study, researchers analyzed 7,245 nutrient samples from 801 marine and freshwater fin fish and invertebrates. While protein content was similar among different seafood sources, scientists found significant variation in the concentrations of calcium, iron and fatty acids.
Fish and invertebrates from biodiverse ecosystems featured a more robust supply of micronutrients.
"While we have known that biodiversity on land is important for benefits such as forest production, this study provides new evidence that the benefits of biodiversity in oceans and freshwaters are as great as on land," Bernhardt said.
"Ecological concepts of biodiversity can deepen our understanding of nature's benefits to people and unite sustainability goals for biodiversity and human well-being," Bernhardt said.
to human health, seafood nutrition
New research shows that when land is more developed and fragmented, as well as less biodiverse, species that are more efficient at spreading disease tend to proliferate. Photo by Cary Institute Photo Archive
April 5 (UPI) -- Biodiversity provides human health benefits on the land and in the water, according to a pair of newly published studies.
Previous studies have highlighted many of the ways biodiversity offers indirect benefits to human health -- by encouraging pollination, for example. But new research suggests biodiversity also provides direct health benefits by keeping humans from getting sick.
New research shows that when land is more developed and fragmented, as well as less biodiverse, species that are more efficient at spreading disease tend to proliferate. Photo by Cary Institute Photo Archive
April 5 (UPI) -- Biodiversity provides human health benefits on the land and in the water, according to a pair of newly published studies.
Previous studies have highlighted many of the ways biodiversity offers indirect benefits to human health -- by encouraging pollination, for example. But new research suggests biodiversity also provides direct health benefits by keeping humans from getting sick.
According to one new study, published Monday in the journal PNAS, biodiversity helps minimize the risk of zoonotic disease outbreaks.
"There's a persistent myth that wild areas with high levels of biodiversity are hotspots for disease," lead study author Felicia Keesing said in a press release.
"More animal diversity must equal more dangerous pathogens. But this turns out to be wrong. Biodiversity isn't a threat to us, it's actually protecting us from the species most likely to make us sick," said Keesing, a professor at Bard College and visiting scientist at the Cary Institute of Ecosystem Studies.
Diseases like COVID-19, SARS and Ebola all emerged in animal populations before making the jump to humans. But they are just a few of millions of viruses circulating among animal populations, most of which will never infect a single human.
To better understand the origins of zoonotic diseases, scientists surveyed scientific literature and found certain species and ecosystems are more likely to produce and pass along zoonotic diseases to humans.
"There's a persistent myth that wild areas with high levels of biodiversity are hotspots for disease," lead study author Felicia Keesing said in a press release.
"More animal diversity must equal more dangerous pathogens. But this turns out to be wrong. Biodiversity isn't a threat to us, it's actually protecting us from the species most likely to make us sick," said Keesing, a professor at Bard College and visiting scientist at the Cary Institute of Ecosystem Studies.
Diseases like COVID-19, SARS and Ebola all emerged in animal populations before making the jump to humans. But they are just a few of millions of viruses circulating among animal populations, most of which will never infect a single human.
To better understand the origins of zoonotic diseases, scientists surveyed scientific literature and found certain species and ecosystems are more likely to produce and pass along zoonotic diseases to humans.
RELATED Peatland conservation may prevent new diseases from jumping to humans
"Research is mounting that species that thrive in developed and degraded landscapes are often much more efficient at harboring pathogens and transmitting them to people," said co-author Rick Ostfeld, disease ecologist at the Cary Institute.
"In less-disturbed landscapes with more animal diversity, these risky reservoirs are less abundant and biodiversity has a protective effect," Ostfeld said.
The research showed animals that live fast and die young -- investing lots of evolutionary capital into reproduction, but so much into adaptive immune systems -- are more likely to pass novel diseases along to humans and other animals.
"Research is mounting that species that thrive in developed and degraded landscapes are often much more efficient at harboring pathogens and transmitting them to people," said co-author Rick Ostfeld, disease ecologist at the Cary Institute.
"In less-disturbed landscapes with more animal diversity, these risky reservoirs are less abundant and biodiversity has a protective effect," Ostfeld said.
The research showed animals that live fast and die young -- investing lots of evolutionary capital into reproduction, but so much into adaptive immune systems -- are more likely to pass novel diseases along to humans and other animals.
RELATED Land use changes could increase risk of disease outbreaks
These types of animals tend do well -- or at least better than others -- in degraded ecosystems, which may explain why researchers found animals credited with the spread of zoonotic diseases were less likely to be species of conservation concern.
"When we erode biodiversity, we favor species that are more likely to be zoonotic hosts, increasing our risk of spillover events," Ostfeld said. "Managing this risk will require a better understanding of how things like habitat conversion, climate change and over-harvesting affect zoonotic hosts -- and how restoring biodiversity to degraded areas might reduce their abundance."
Researchers suggest efforts to prevent -- as well as to predict and prepare for -- the next spillover event should focus less on particular species and more on groups of animals and the habitats where they are mostly likely to congregate.
"Restoration of biodiversity is an important frontier in the management of zoonotic disease risk. Those pathogens that do spill over to infect humans -- zoonotic pathogens -- often proliferate as a result of human impacts," Keesing said. "As we rebuild our communities after COVID-19, we need to have firmly in mind that one of our best strategies to prevent future pandemics is to protect, preserve, and restore biodiversity."
In a separate study, published Monday in the journal PNAS, researchers at Yale University looked at the effects of biodiversity on seafood nutrition.
The Yale analysis showed seafood sourced from biodiverse ecosystems features higher levels of nutrients -- including vitamins, minerals and fatty acids -- than seafood from areas of the ocean that have been degraded by overfishing, pollution and climate change.
"What we found is that biodiversity is crucial to human health," co-author Joey Bernhardt, an ecologist and postdoctoral fellow at Yale, said in a press release.
Though there is much scientists still don't understand about COVID-19, a mounting body of research suggests diet is intimately linked with the body's immune system.
The latest research suggests even calories from the same types of food aren't always equal, and the findings could have significant implications for coastal communities that consume lots of seafood.
For the study, researchers analyzed 7,245 nutrient samples from 801 marine and freshwater fin fish and invertebrates. While protein content was similar among different seafood sources, scientists found significant variation in the concentrations of calcium, iron and fatty acids.
Fish and invertebrates from biodiverse ecosystems featured a more robust supply of micronutrients.
"While we have known that biodiversity on land is important for benefits such as forest production, this study provides new evidence that the benefits of biodiversity in oceans and freshwaters are as great as on land," Bernhardt said.
"Ecological concepts of biodiversity can deepen our understanding of nature's benefits to people and unite sustainability goals for biodiversity and human well-being," Bernhardt said.
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