Global warming may cool plants' 'love connection'
Deep in the forest at Shaw Nature Reserve, the heartbreak and anguish of something like Craigslist’s “Missed Connections” section – where people look online for people they saw in person but weren’t able to talk to – is being played out on a massive scale.
But here the stakes are much higher, and no humans are involved. For years, researchers studying plants at Shaw have seen flowering plants blooming at different times – and for different lengths of time – than in the past.
The problem is that the insects that pollinate them haven’t gotten the message. They still come loaded with pollen at the same time they always have. By then, though, the plants they expect to see – and rely on for food – aren’t there.
“If that relationship gets messed up – that’s not something we can fix,” said Kyra Krakos, an assistant biology professor at Maryville University. “Humans can’t do the work of bees.”
This summer, Krakos, along with a group of five undergraduate researchers, has led an investigation into the effect of global warming on plants and pollinators in Shaw.
Each student is studying a single plant species in depth, mapping its relationships to different pollinators and seeing how its behavior has shifted over time. Their research feeds into the larger project of looking at the effects of climate change.
Though Krakos’ project is only in its first year, she and her students can compare the behavior of plants now with their behavior in the past because of Edgar Anderson, a botanist who kept detailed weekly records of everything flowering in the preserve from 1937 to 1942.
Since Shaw has been set off and preserved since the late 1800s, it allows for comparisons possible in few other places.
“It’s very hard in studies of climate change to compare the past to the present,” Krakos said, explaining why Shaw is so unique. She hopes to attract grant money to help bring more research attention to the reserve.
“We’re hoping this project will be the jumping-off point,” she said.
From May till mid-July, Krakos and her students worked outside in Shaw, observing pollination and catching pollinating insects. Since then, the students have worked in a lab adjacent to the Missouri Botanical Garden, scraping the pollen still stuck to the insects off and examining it under the microscope.
“Often, what people assume is the pollinator is not,” Krakos said. “[The students] really get at that detailed relationship of what’s happening between plant and pollinator.”
To observe these relationships, the students had to hike into Shaw and fan out in different directions, looking for the plants they were each studying. Then there were long periods of sitting stock-still in the sun, waiting for pollinators to come before catching them.
“You definitely have to have a plan B and a plan C,” said Tim Payne, one of the students.
In addition to the environmental and ecological consequences of warming, Krakos said changes in blooming periods and lengths could mean serious problems for farmers.
Although warmer temperatures typically extend growing seasons, having too many plants competing at once for a limited amount of pollen means that many won’t be fertilized.
When plants can’t reproduce, their numbers will go down, resulting in less food for the pollinating insects. About 80 percent of plants need pollinators, according to Krakos, so any disruption sends ripples through the ecosystem.
“A longer growing season sounds great, unless it ends in a battle for love,” Krakos said.
It doesn’t have to. Krakos says if people, especially farmers, took some simple steps, like leaving at least a thin belt of native species around their gardens or plots of corn or wheat, or if they took steps to attract native bees, they could preserve essential pollinating species.
“It’s not an us-and-them sort of thing,” Krakos said. “We really can live in harmony with pollinators.”