Cicada infestations boost nutrients for forests

CBC News Online ^ | 11/25/2004

[Fatalis]

WASHINGTON - Insects that emerge every 17 years in the eastern United States provide valuable nutrients to forest ecosystems when they die, an ecologist says.

The Brood X cicadas emerge from their burrows on a regular cycle, sing to attract a mate and lay eggs before dying on the forest floor.

Cicadas cling to a leaf after crawling their way above ground(AP Photo)

Last spring, the insects swarmed forests, raising concerns about their effects on the ecosystem.

Scientists had noticed forests tended to have higher levels of the nutrient nitrogen in their leaves after cicadas emerged and tree growth tended to increase.

The infestation gave researchers a chance to test the impact of cicada carcasses on soil and plants.

Researchers at the University of California, Davis, studied cicada-infested areas in the U.S. in 2002, 2003 and 2004.

In an experiment, Louie Yang measured the levels of nutrients in plots with cicadas compared to control plots without extra insects.

The type of nitrogen used by plants jumped from 199 per cent to 412 per cent in soil littered with cicada carcasses, Yang's team found.

Populations of bacteria and fungi also increased, the researchers said in Friday's issue of the journal Science.

Plants appeared to benefit from the extra nutrients. Bellflower, a plant that commonly grows on the forest floor in cicada territory, produced seeds that were nine per cent larger.

The plants also produced leaves containing 12 per cent more nitrogen than those that grew in cicada-free soil.

The nitrogen from the cicadas came in a unique form, which allowed the researchers to trace it to the insects.

[SteveMcKing]

I found it interesting there are other cicada species that emerge in different cycles (not 17 years, something like 6 or 8 or something).

[Fatalis]

FYI

[E. Pluribus Unum]

[hometoroost]

"Last spring, the insects swarmed forests, raising concerns about their effects on the ecosystem.

Comments like this show why many people have stopped listening to the eco-wienies. These things have been coming and going for hundreds of thousands maybe millions of years. The earth is a well-designed and durable place.