Tropical plants may be more adaptable to climate change
Tropical plants may be more adaptable to climate change
mongabay.com
May 7, 2007
Tropical plants may be more adaptable to environmental change by extracting nitrogen from a variety of sources, reports a study published in the May 7 early online edition of The Proceedings of the National Academy of Sciences.
Measuring the soil content of nitrate, ammonia, and dissolved organic nitrogen and determining their contribution to plant growth, a team of researchers lead by Benjamin Houlton of the Carnegie Institution’s Department of Global Ecology found that unlike temperate species, tropical plants can uptake nitrogen from a variety of sources. The results offer hope that tropical species will prove more adaptable to climate change.
“When it comes to nitrogen, the tropical plants we studied behave like kids at a pizza party—they may prefer pepperoni, but if only plain cheese is available, they’ll still have a slice,” said Houlton. “This result gives a glimmer of hope that tropical ecosystems may have the capacity to adjust to certain aspects of climate change.”
 Vines in Hawaii. |
Working on the Hawaiian island of Maui, the researchers found that nitrate was most readily available in dry areas, while ammonium was prevalent in wet areas. Plants could use both nitrogen sources interchangeably depending on availability.
“It really is quite striking; once the soil gets wet and nitrate drops below a certain threshold, the tropical plants all begin using ammonium in near-perfect unison,” Houlton explained. “If these diverse plant species can be flexible in their nitrogen metabolism—thought to be non-negotiable in many temperate ecosystems—then maybe they can react to other environmental stresses just as gracefully. Still, our results will need further testing in vast areas of the tropics before we will know how well they truly represent the entire ecosystem.”