A new study finds that many grasslands in the United States are far more productive than previously thought, despite a lack of data.
The study, published in the journal Nature Climate Change, analyzed data from the National Wildlife Refuge System (NWRSS), which manages the vast tracts of land on which all of the world’s grasslands are found.
The researchers looked at the productivity of 7,872 grasslands across 26 states, using data from USDA’s National Agricultural Statistics Service.
They found that there was “significantly higher grassland productivity in states with high percentages of land that was grassland” than in states that had a higher percentage of “other land types” such as deserts, prairies, and wetlands.
The authors note that the study’s conclusion doesn’t necessarily mean that the grasslands of the U.S. are in fact “naturally productive.”
They just say that the amount of productive land is much higher than the amount in other land types.
“The most important finding of the study is that grasslands with large surface area (e.g., areas with an average area of more than 20 square miles), particularly those with greater biomass, tend to be more productive,” the authors write.
“The amount of productivity increases with land area, as shown in Figure 2.”
“The authors are right to emphasize that productivity is not a fixed quantity,” said study co-author Michael W. Smith, a doctoral candidate in the University of Utah’s Department of Ecology and Evolutionary Biology.
“In many grassland ecosystems, the amount produced per hectare is much greater than the land area.”
The study was based on USDA’s land use data from 2003 through 2014.
It used data from 2011 to 2013 to determine what percentage of the land was grasslands.
The number of grasslands per square mile was measured for each state and the percentage of land in each state was also calculated.
The authors found that a small number of states with relatively high percentages had very low grassland numbers.
The remaining states with low grasslands were in the middle.
The report is the first comprehensive look at the amount and productivity of grassland across the country, Smith said.
It’s not the first time researchers have looked at grasslands, but the number of studies looking at them is “not a lot,” he said.
For example, there are more than 30,000 species of grasses and shrubs in the U, Smith noted.
But just because there are many species of these grasses or shrubs doesn’t mean that they’re “all-natural.”
“We know that they’ve been cultivated over time, and we know that some have adapted to changing conditions,” Smith said, adding that the “more we understand the biology of grass, the more we can do to reduce their impact on our ecosystem.”
This study suggests that grassland landscapes are not natural ecosystems and that they may be “often poorly managed,” Smith added.
“So the question is: How do we make grasslands better managed?
And the answer is to use more natural materials and to do so by planting them in better locations.”
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