salty joe
06-23-2011, 05:29 AM
Why diversity rules
Experiment shows how a multitude of species gets the job done
By Susan Milius
Web edition : Wednesday, April 6th, 2011
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MIX UPA variety of algae (magnified here) flourish in natural streams and take the nitrogen they need to grow from of the water, thus scrubbing up some vexing nitrate pollution.Danuta Bennett
A novel experiment in cleaning nitrate pollution out of water gives a new look at what’s so powerful about the diversity of life.
In lab setups that mimicked freshwater streams’ lazy pools and rushing freshets, a mix of algal species proved more than four times as efficient at taking up nitrates than a single supercleaner species living in the same kind of stream, reports ecologist Bradley Cardinale of the University of Michigan in Ann Arbor. And when he added a mix of algae to simplified stream setups lacking a variety of living conditions, or niches, the diversity bonus didn’t show up.
What gives diversity its efficiency, then, is not just some superspecies that happens to be in the mix, Cardinale concludes. Instead, the long-noted diversity bonus in nutrient uptake comes from the way a mix of species can expand and take advantage of the many different niches in an environment, Cardinale reports in the April 7 Nature.
Experiment shows how a multitude of species gets the job done
By Susan Milius
Web edition : Wednesday, April 6th, 2011
Text Size
Enlarge
MIX UPA variety of algae (magnified here) flourish in natural streams and take the nitrogen they need to grow from of the water, thus scrubbing up some vexing nitrate pollution.Danuta Bennett
A novel experiment in cleaning nitrate pollution out of water gives a new look at what’s so powerful about the diversity of life.
In lab setups that mimicked freshwater streams’ lazy pools and rushing freshets, a mix of algal species proved more than four times as efficient at taking up nitrates than a single supercleaner species living in the same kind of stream, reports ecologist Bradley Cardinale of the University of Michigan in Ann Arbor. And when he added a mix of algae to simplified stream setups lacking a variety of living conditions, or niches, the diversity bonus didn’t show up.
What gives diversity its efficiency, then, is not just some superspecies that happens to be in the mix, Cardinale concludes. Instead, the long-noted diversity bonus in nutrient uptake comes from the way a mix of species can expand and take advantage of the many different niches in an environment, Cardinale reports in the April 7 Nature.