A new insight into global photosynthesis, the chemical process governing how ocean and land plants absorb and release carbon dioxide, has been revealed in research that will assist scientists to more accurately assess future climate change.
In a paper published today in Nature, a team of US, Dutch and Australian scientists have estimated that the global rate of photosynthesis, the chemical process governing the way ocean and land plants absorb and release CO2, occurs 25% faster than previously thought.
From analysing more than 30 years of data collected by Scripps Institution of Oceanography, UC San Diego including air samples collected and analysed by CSIRO and the Bureau of Meteorology from the Cape Grim Air Pollution Monitoring Station, scientists have deduced the mean rate of photosynthesis over several decades and identified the El Nino-Southern Oscillation phenomenon as a regulator of the type of oxygen atoms found in CO2 from the far north to the south pole.
"Our analysis suggests that current estimates of global primary production are too low and the refinements we propose represent a new benchmark for models to simulate carbon cycling through plants," says co-author, Dr Colin Allison, an atmospheric chemist at CSIRO's Aspendale laboratories.
The study, led by Dr Lisa Welp from the Scripps Institution of Oceanography, California, traced the path of oxygen atoms in CO2 molecules, which tells researchers how long the CO2 has been in the atmosphere and how fast it had passed through plants. From this, they estimated that the global rate of photosynthesis is about 25 percent faster than previously thought.
"It's difficult to measure the rate of photosynthesis for forests, let alone the entire globe. For a single leaf it's straightforward, you just put it in an instrument chamber and measure the CO2 decreasing in the chamber air," said Dr Welp.
|Contact: Craig Macaulay|