Coral study provides clues to reef damage in Madagascar

Sep 05, 2012
Coral study provides clues to reef damage in Madagascar
Coral cores--These drill samples show luminescence under UV light, x-ray and normal light (l-r). The bands in the samples on the left and right correspond, and indicate massive discharges of organic matter from rivers taken up by the corals.

(Phys.org)—A group of international researchers, including one from UWA Oceans Institute, has used coral sampling to assess the impact of river run-offs in a bay in north-eastern Madagascar.

The research was carried out in a bay favoured by whales to rear their calves, in effect, making it a 'whale kindergarten'.

"The aim of the study was to test if we can use coral cores to assess the impact of various small mountain rivers on adjacent coral reefs in Antongil Bay, the largest bay on the island of Madagascar in the west Indian Ocean," said Dr Jens Zinke, of UWA Oceans Institute.

"The bay is significant because every year up to 300 come into this bay between June to October to raise their young and protect them from predators."

As part of the study, researchers drilled coral samples from the reef in the bay. By exposing the coral samples to various lights, luminescent bands - in effect, similar to the of a tree - provided a long-term record of river run-off reaching the coral reefs in Madagascar.

"For instance, the corals closest to the river plume at Nosy Mangabe island reserve showed clear signs of disease and distorted growth patterns," Dr Zinke said.

"Nevertheless, these reefs were adapted to sediment discharge for hundreds of years and survived several cyclone induced mass erosion events in the past."

The research findings will be used to help guide on the island and the management of its marine parks.

"With these results, we can inform conservation managers on the best choice of marine parks and the likelihood of adverse impacts on and fisheries caused by high levels of in reefs outside the bay near highly deforested plains," Dr Zinke said.

The study, Spatial linkages between proxies of terrestrial run-off across a large embayment in Madagascar, is published in the journal Biogeosciences.

Explore further: US delays decision on Keystone pipeline project

More information: doi:10.5194/bg-9-3063-2012

add to favorites email to friend print save as pdf

Related Stories

New study predicts where corals can thrive

Apr 16, 2008

The Wildlife Conservation Society (WCS) and the International Institute for Geo-Information Science and Earth have developed a new scientific model that accurately maps where coral reefs are in the most trouble and identifies ...

Recommended for you

US delays decision on Keystone pipeline project

22 hours ago

The United States announced Friday a fresh delay on a final decision regarding a controversial Canada to US oil pipeline, saying more time was needed to carry out a review.

New research on Earth's carbon budget

Apr 18, 2014

(Phys.org) —Results from a research project involving scientists from the Desert Research Institute have generated new findings surrounding some of the unknowns of changes in climate and the degree to which ...

User comments : 0

More news stories

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.

Health care site flagged in Heartbleed review

People with accounts on the enrollment website for President Barack Obama's signature health care law are being told to change their passwords following an administration-wide review of the government's vulnerability to the ...