Biodiversity Of Earth’s Richest Plant Kingdom Under Fire
In response to climate change, will a postage-sized-domain move uphill–and ultimately out of room?
Climate change is on your porch and in your backyard and living room–anywhere you bedeck with flowering plants.
Global warming affects favorite flowers of garden and vase. This is true of plants around the world, including the proteas and the pelargoniums native to South Africa.
Pelargoniums are wild ancestors of common geraniums. Proteas, with their vase-shaped bracts surrounding pencil-thin flowers, look like brightly-colored sea anemones.
During the Northern Hemisphere’s winter, summer comes to South Africa and proteas and pelargoniums bloom in riotous color. On steep, rocky slopes, their red and pink flowers dot the hillsides.
“As one of the most diverse plant groups in South Africa, the pelargoniums have a variety well beyond what’s available at even the largest U.S. nursery,” says Carl Schlichting, an ecologist and evolutionary biologist at the University of Connecticut who specializes in these flowering plants.
But pelargoniums and proteas such as the king protea, which measures 12 inches across and is the national flower of South Africa, are under fire. Some will become extinct. Some already have.
In a region where average temperatures have significantly warmed over the past 30 years, South Africa’s–if not the world’s–most unusual flowers are besieged.
In response, they’re moving uphill to cooler or wetter spots. When will they run out of room? No one knows for sure. But time is of the essence in learning about this ecosystem, says Schlichting.
Despite centuries of discovery, most of the planet’s biodiversity remains unknown. The scale of that unrecognized biodiversity is a vital question, scientists believe, given its rapid and permanent loss around the globe.
To respond to the need for more knowledge and a better understanding of Earth’s biodiversity, the National Science Foundation (NSF) recently awarded 25 grants in its Dimensions of Biodiversity campaign.
The effort is part of NSF’s Science, Engineering and Education for Sustainability (SEES) initiative.
Schlichting and colleagues comprise one of the research teams funded.
“By establishing networks of interdisciplinary, globally-engaged scientists, Dimensions of Biodiversity will have a lasting effect on biodiversity science,” says John Wingfield, NSF assistant director for Biological Sciences. “It has the potential to transform the way we conduct biological research in this arena.”
The Dimensions of Biodiversity campaign is important, believes Wingfield, because assessing the living diversity of Earth is not as straightforward as simply listing species.
The campaign is transforming how the role and scope of life on Earth is described and understood, he says.
It promotes novel, integrated approaches to identifying and comprehending the evolutionary and ecological significance of biodiversity in today’s changing environment and in the geologic past.
“Dimensions of Biodiversity is accelerating the pace of biodiversity research and discovery, and it enables scientists to think at grand scales,” says Joann Roskoski, NSF deputy assistant director for Biological Sciences.
“Collaborative teams have formed to tackle some of the big questions using novel and integrative techniques,” she says. “Taxonomists are talking to geneticists; geneticists to ecologists; and ecologists to taxonomists. This is not business as usual.”
With the loss of Earth’s biodiversity, biologists have found, links in the web of life that provide ecosystem services are being lost; an understanding of the history and future of the living world is being forfeited; and beneficial discoveries in the domains of food, fiber, fuel, pharmaceuticals and bio-inspired innovation are being eliminated.
That reality has stimulated the NSF awards, co-funded by NSF’s Directorates for Biological Sciences and Geosciences.
“Dimensions may accomplish in 10 years what, with a piecemeal approach, would have taken 50 years–a half-century we can no longer wait,” says Roskoski.
Proteas are the keystone species of South Africa’s Cape Floral Kingdom, the smallest but, biologists say, the richest of Earth’s six plant kingdoms.
The Cape Floral Kingdom is the size of a postage stamp, comparatively speaking. It has the highest plant biodiversity, however, of anywhere on the planet.
About 9,000 plant species, 70 percent of which live nowhere else, are found there in what’s called the fynbos ecosystem. Just to the north lies another, yet more diverse, desert-like ecosystem, the succulent karoo.
Near South Africa’s Cape of Good Hope, leathery-leaved fynbos plants cover the mountains, valleys and coastal plains. Proteas and pelargoniums thrive despite nutrient-poor soils and high winds.
Schlichting’s research focuses on how proteas and pelargoniums have diversified over the last 15 million years during periods of climate change in southern Africa.
“Contemporary climate change will drive responses at all levels of biodiversity, from the traits of individuals to distributions of species and biomes,” says Schlichting.
“Our team hopes to combine an understanding of past evolutionary patterns with an assessment of modern diversity to make predictions about the future of plant communities.”
Some pelargonium plants, for example, may be drought-avoiders, while others are drought-tolerators. Schlichting is discovering which ones are which.
These traits may be linked with the environment, he and others have found, and may indicate patterns of local adaptation.
“This study looks at one of the most diverse floras of the world,” says Sam Scheiner, program director in NSF’s Division of Environmental Biology, “and connects plant physiology with the evolutionary processes driving diversification. It is one of the most comprehensive views of this process, and promises to greatly expand our knowledge.”
As Earth’s climate warms, species like proteas and pelargoniums will try to keep pace by adapting to new conditions or by moving to their preferred temperature and rainfall ranges.
Protea seeds, for example, are carried on the wind to new locations. Those that become rooted in cooler or wetter areas will survive.
“We may not have much time to understand why there is such a rich diversity of pelargoniums and proteas,” says Cynthia Jones, a University of Connecticut scientist working on the project, “before they begin to disappear.”
From porches, backyards and living rooms. And from fynbos and succulent karoo.
Image Caption: A Cape sugarbird rests on a protea flower in Kirstenbosch Gardens, South Africa. (Credit: Adam Wilson, University of Connecticut)
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