It seems moving plants to lower altitudes is not necessarily beneficial in the longterm: “10-year research project show short-term warming boost, with subsequent degradation of ecosystem”
Global warming can boost short-term plant growth, but over time, warming temperatures disrupt the nitrogen cycle and quickly lead to the deterioration of dry grassland ecosystems, according to a 10-year study done by Northern Arizona University scientists.
The researchers subjected four grassland ecosystems to simulated climate change during the decade-long study. Plants grew more the first year in the global warming treatment, but this effect progressively diminished over the next nine years, and finally disappeared.
The grasslands studied were typical of those found in northern Arizona along elevation gradients from the San Francisco Peaks down to the great basin desert.
“We were really surprised by the pattern, where the initial boost in growth just went away,” said Zhuoting Wu, NAU doctoral graduate in biology. “As the ecosystems adjust, the responses changed.”
To carry out the long-term project the researchers simply picked up sections of grasslands and moved them downhill to warmer elevations to simulate global warming impacts.
“One thing that changes with elevation is rainfall,” said NAU Biological Sciences professor Bruce Hungate, lead author of the paper. Hungate explained that the study team used interceptors and collectors to adjust for the differences in moisture to prevent the results from being skewed.
The researchers found that long-term warming resulted in loss of native species and encroachment of species typical of warmer environments, pushing the plant community toward less productive species.
Not sure I’m convinced simply moving sections of grasslands downhill really simulates an enhanced greenhouse world – what about increased atmospheric carbon dioxide and the increased humidity that is supposed to accompany it?