The success of many North American crops partly depends on ground beetles, small insects that eat pests and weed seeds that could otherwise damage crops. But a new study by researchers in the U. S. and Canada suggests not all of the nearly 2,000 species of ground beetles found in North America will survive climate change. Some could decline. And that could have a far-reaching impact on agriculture, forestry, and conservation.
By analyzing data on 136 different ground beetle species across continental North America, Puerto Rico and Hawaii, the researchers found that a species' chance of success in a changing climate depends on several important factors, such as its habitat preference, body size, and whether it flies, climbs or runs.
"We found that less mobile, nonflying ground beetles, which are critical pest control agents, are more likely to decline over time in a warmer, dryer climate," said Tong Qiu, who led the study. "That means you're going to have more pests that can impact agricultural and forest ecosystems." But there is reason for hope, Qiu added, because the analysis also showed that habitat conservation can lessen these effects and reverse the trends in some areas.
"We hope conservation biologists will use this information and the online map that we created to better manage habitats for insects in general. Ground beetles are very beneficial to ecosystems, but they're largely invisible to the average person. In this paper we're showing the broad impacts they have on whole communities in forested and agricultural ecosystems," said Qiu.
The researchers used ground beetle count data from the National Science Foundation's National Ecological Observatory Network (NEON) and from 11 previously published studies to measure and map the beetles' distribution across North America. Habitat information, such as the location of gap s in forest canopies and the density of plants on a forest floor, was obtained by using NEON's imaging instruments to create detailed three-dimensional images of landscapes. They then entered the data collected into a computer model to simulate (模拟) climate changes to study how the insects would respond.
