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?
True, plus how deep were these movable trays that the plants were put in to move them? Even worse, if the plants were placed directly into the soil, retarded growth would occure, simply because transplanting the plants would destroy fragile root-structures, DEPRESSING the plant’s growth. So is it dryer climes, or crowded/savaged root systems? I can grow all sorts of weeds in a yard, with very little water, here in Arizona.
These people are so enamored with temperature that they can’t see anything else. The average temperture in say, Georgia, is more than a few degrees higher than the average temperature in Maine. Yet both have thriving ecosystems and people have no problem living in both. Life is much less sensitive to a few degrees difference than the GWC crowd posulate.
How did the researchers increase the carbon dioxide concentration that drives the temperature increases in the virtual world. Would the warmer temperature not be preceded by higher carbon dioxide concentrations?
I’m glad that they very scientifically eliminated all variables other than heat as influencing factors on these plants.
We all know that heat is the only factor for a plant acclimated to the mountains and transplanted to the dessert.
What? That’s not true? Silly me.
What was their hypothesis? Seems like too much research gets reported that conforms with a predetermined outcome; not a true testing of hypothesis. Is there any real research done in this country any more?
The hottest region here in Australia still has a thriving plant community after one of the warmest years in 100 years in the Great Sandy Desert, 2010. http://pindanpost.com/2011/04/19/desert-heat/
Rainfall rules.
We transplanted the controls, too, in situ, so they experienced the same effects of transplanting (potential root constriction, etc.), save the changes in climate. We did not manipulate CO2. If you change too many things at once, it’s hard to figure out what causes what. So we focused on temperature and precipitation. We were really surprised to see such modest effects of precipitation, compared to those of temperature. Rainfall often rules, absolutely, so isn’t it interesting that temperature had such a strong effect?