Extreme weather threatens rich ecosystemsApril 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.
Related Ecosystems Current Events and Ecosystems News Articles
Ecologists advise an increase in prescribed grassland burning to maintain ecosystem
Kansas State University researchers have found a three-year absence of fire is the tipping point for the tallgrass prairie ecosystem and advise an increase in burning.
Hydrothermal vents, methane seeps play enormous role in marine life, global climate
The hydrothermal vents and methane seeps on the ocean floor that were once thought to be geologic and biological oddities are now emerging as a major force in ocean ecosystems, marine life and global climate.
Shifting bird distribution indicates a changing Arctic
Shifts in the distribution of Spectacled Eiders, a predatory bird at the top of the Bering Sea's benthic food web, indicate possible changes in the Arctic's marine ecosystem, according to new research in The Condor: Ornithological Applications.
PNNL helps lead national microbiome initiative
Scientists at the U.S. Department of Energy's Pacific Northwest National Laboratory are playing a central role as the nation devotes more than $500 million to understand communities of microorganisms and their role in climate science, food production and human health.
3-D model reveals how invisible waves move materials within aquatic ecosystems
Garbage, nutrients and tiny animals are pushed around, suspended in the world's oceans by waves invisible to the naked eye according to a new 3-D model developed by mathematicians at the University of Waterloo.
Underwater grass beds have ability to protect and maintain their own health
An expansive bed of underwater grass at the mouth of the Susquehanna River has proven it is able to "take a licking and keep on ticking."
Spring comes sooner to urban heat islands, with potential consequences for wildlife
With spring now fully sprung, a new study by University of Wisconsin-Madison researchers shows that buds burst earlier in dense urban areas than in their suburban and rural surroundings. This may be music to urban gardeners' ears, but that tune could be alarming to some native and migratory birds and bugs.
Ecosystems with many and similar species can handle tougher environmental disturbances
How sensitive an ecosystem is to unforeseen environmental stress can be determined, according to Daniel Bruno, previous visiting researcher at Umeå University.
Antarctic fossils reveal creatures weren't safer in the south during dinosaur extinction
A study of more than 6,000 marine fossils from the Antarctic shows that the mass extinction event that killed the dinosaurs was sudden and just as deadly to life in the polar regions.
How much can a mode-2 wave move?
Look out over the ocean and you might get the impression that it's a mass of water acting as a single entity.
More Ecosystems Current Events and Ecosystems News Articles