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Pressures from grazers hastens ecosystem collapse from drought

ScienceDaily (January 11, 2017)

Titre : Pressures from grazers hastens ecosystem collapse from drought

ScienceDaily (January 11, 2017)
Ecosystem collapse from extreme drought can be significantly hastened by pressures placed on drought-weakened vegetation by grazers and fungal pathogens, a new study finds. The study’s experimental evidence shows that the natural enemies of plants play a major role in lowering resilience to drought and preventing recovery afterward. The finding may be applicable to a wide range of ecosystems now threatened by climate-intensified drought, including marshes, mangroves, forests and grasslands.

The researchers found that these tipping points can happen much sooner than current models predict because of the added pressures placed on drought-weakened plants by grazing animals and fungal pathogens. The scientists conducted their field work between 2009 and 2015 in salt marshes in China’s Yellow and Liao river deltas. The marshes, which are famed for their year-round purplish-red color, are among the last protected native coastal wetlands in China. The marshes experienced widespread vegetation die-off following an extreme drought in 2011. The researchers performed a series of experiments before, during and after the drought to test how pressures from heavy grazing by crabs — the main natural enemy of plants in the protected marshes — affected resilience to and recovery from the drought

Story Source  : Duke University.

Annonce (ScienceDaily)

Page publiée le 20 janvier 2018