Science Current Events | Science News | Brightsurf.com
 

Extreme weather threatens rich ecosystems

April 02, 2012
Extreme weather such as hurricanes, torrential downpours and droughts will become more frequent in pace with global warming. Consequently, this increases the risk for species extinction, especially in bio diverse ecosystems such as coral reefs and tropical rainforests.

Human impact means that flora and fauna become extinct at a rate 100-1000 times higher than normal. Climate change has been deemed as one of the main causes of species depletion.

A research team in theoretical biology at Linköping University has, with the help of mathematical modelling and simulation, studied how the dynamics of different types of ecosystems may be affected by significant environment fluctuations.

Linda Kaneryd, doctoral student and lead author of a study recently published in the journal, Ecology and Evolution, says the results were surprising. Kaneryd explains,
"Several previous studies of food web structures have suggested that species-rich ecosystems are often more robust than species-poor ecosystems. However at the onset of increased environmental fluctuations, such as extreme weather, we see that extreme species-rich ecosystems are the most vulnerable and this entails a greater risk for a so-called cascading extinction."

In a rainforest or on coral reef there are a wide variety of species of primary producers such as green plants and algae. Since they are competitors, relatively few individuals of the same species exist, subjecting them to a greater risk of extinction should external conditions change. This could result in a depletion of food sources for a species of herbivores that, in turn, affects a predator at the top of the food chain. Biologists call this transformation a cascading extinction.

The opposite would apply to an ecosystem whereby few species exist in large numbers and animal species are adaptable generalists.

The researchers create their model food webs following on from their experiences with real ecosystems; what eats what, the composition of the species' life cycles, and how they interact with others. In this study, external conditions are represented as an increasing and unpredictable variation.

"The model we worked with is quite typical. The next step is to introduce actual, detailed climatic data," informs Bo Ebenman, Professor of Theoretical Biology who supervised Linda Kaneryds thesis.

Linköping University


Related Ecosystems Current Events and Ecosystems News Articles


DNA samples from Purdue, Kew fungi collections provide key to mushroom 'tree of life'
Genetic material from fungi collections at Purdue University and the Royal Botanic Gardens, Kew, helped a team of researchers resolve the mushroom "tree of life," a map of the relationships between key mushroom species and their evolutionary history that scientists have struggled to piece together for more than 200 years.

Climate engineering may save coral reefs, study shows
Geoengineering of the climate may be the only way to save coral reefs from mass bleaching, according to new research.

New national study finds autoimmune disease severely impacts patients
In a new national survey of rheumatoid arthritis (RA) patients, Health Union found a severe impact on quality of life, employment, and ability to afford treatment.

Changes in forest structure affect bees and other pollinators
Over the past century, many forests have shifted from open to closed canopies. The change in forest structure could be contributing to declines in pollinator species, especially native bees, according to a new study by U.S. Forest Service scientists.

EARTH: Flames fan lasting fallout from Chernobyl
In the years following the 1986 Chernobyl nuclear disaster, forest fires billowed plumes of contaminated smoke, carrying radioactive particles throughout Europe on the wind.

Savannahs slow climate change
Tropical rainforests have long been considered the Earth's lungs, sequestering large amounts of carbon dioxide from the atmosphere and thereby slowing down the increasing greenhouse effect and associated human-made climate change.

What did the first snakes look like?
The original snake ancestor was a nocturnal, stealth-hunting predator that had tiny hindlimbs with ankles and toes, according to research published in the open access journal BMC Evolutionary Biology.

Ancient snakes -- a new hiss-tory
The ancestral snakes in the grass actually lived in the forest, according to the most detailed look yet at the iconic reptiles.

Bugs and slugs ideal houseguests for seagrass health
Marine "bugs and slugs" make ideal houseguests for valuable seagrass ecosystems. They gobble up algae that could smother the seagrass, keeping the habitat clean and healthy.

Diverse soil communities can help offset impacts of global warming
Maintaining a healthy and diverse soil community can buffer natural ecosystems against the damaging impacts of global warming, according to a new Yale-led study.
More Ecosystems Current Events and Ecosystems News Articles

© 2015 BrightSurf.com