French islands under threat from rising sea levels

Sep. 17, 2013 — By the year 2100, global warming will have caused sea levels to rise by 1 to 3 meters. This will strongly affect islands, their flora, fauna and inhabitants. A team of researchers from the Ecologie, systematique et evolution (CNRS/Universite Paris-Sud) laboratory studied the impact of rising sea levels on 1,269 French islands throughout the world. Their model shows that between 5% and 12% of these islands could be totally submerged in the future. On a worldwide scale, they predict that about 300 endemic island species are at risk of extinction, while the habitat of thousands of others will be drastically reduced.

This research has been published in the journals Global Ecology and Biogeography (August 2013) and Nature Conservation (September 2013).

The most recent predictions of global warming show that sea levels will rise by between 1 and 3 meters before the end of the century. In some scenarios involving a catastrophic breaking-up of Greenland ice, sea levels are expected to rise by 6 meters. Any such increase will have serious consequences for the populations, flora and fauna of the coastal strip.

The researchers at the Ecologie, systematique et evolution laboratory first concentrated on the effects rising sea levels would have on French islands. Throughout the world, 2,050 French islands of more than a hectare are likely to have animal and plant communities.

The scientists compared the terrain contours of 1,269 of these islands with sea level models, taking into account the fact that sea levels will not rise evenly over the Earth's surface because the sea is not flat: some areas of the ocean will rise higher than others. Results showed that, even if sea levels only rose by one meter, France would lose 6% of its islands (12% in the case of a 3-meter rise). French Polynesia and New Caledonia would be the worst affected: two thirds of the islands that would be submerged are in these archipelagos. There are French islands in all of the world's oceans, at all latitudes and with many different types of geology and ecology. Extrapolating their results to the 180,000 islands in the world, the scientists believe that the Earth could lose 10,000 to 20,000 islands before 2100.

The researchers went on to look at the biodiversity loss that could result from sea-level rise, notably in certain biodiversity hotspots such as the Mediterranean, the Philippines and New Caledonia. Twenty percent of the world's biodiversity is found on islands, including a very large proportion of endemic species.

The Philippines, Indonesia and the Caribbean are the most vulnerable areas: at least 300 endemic species, mostly plants, are seriously threatened by rising sea levels. Yet even this figure is a conservative estimate, as the researchers only considered species whose distribution areas would be totally submerged by 2100. They did not include the species that would lose 70%, 80% or even 90% of their natural range, nor additional factors such as lateral erosion or centennial tides, which can make large expanses of the coastal strip inhospitable for many species. Neither did they include natural disasters like cyclones.

This work shows how much of a threat rising sea levels pose to the biodiversity of island ecosystems, highlighting the necessity to take account of the consequences of this unstoppable process in designing policies for the conservation and protection of endangered species.

View the original article here

An unprecedented threat to Peru's cloud forests

Sep. 11, 2013 — Peru's cloud forests are some of the most biologically diverse ecosystems in the world. A profusion of tree and plant species as well as one third of Peru's mammal, bird and frog species make their home in these perennially wet regions, located along the eastern slopes of the Andes Mountains. The high elevation (6,500-11,000 feet), and remote location of these areas makes them some of the hardest to reach and therefore hardest to study ecosystems in the world. To date, scientists only believe a fraction of cloud forest tree and plant species have been discovered.

This massive array of underexplored biodiversity will face an unprecedented threat before the end of the century.

Now, researchers at Wake Forest University in Winston-Salem, N.C. have pieced together startling new evidence that shows rapid 21st century warming may spell doom for tree species in Peruvian cloud forests, with species losing 53-96 percent of their populations.

Stuck in a Hot Place

The habitats of most Andean plants-and therefore the habitats of the organisms that use them for food and shelter- are determined largely by temperature. Temperatures change quickly on the slopes of the Andes due to the region's steep terrain. This means the vast majority of trees and plants only can live in a range that extends a few hundred meters.

"I could be standing among a group of one tree species and throw a rock completely across their ranges," says David Lutz, the paper's lead author and a former postdoctoral associate at Wake Forest University. Lutz, who is now a post-doctoral research associate at Dartmouth College in New Hampshire, says this means cloud forest trees are particularly sensitive to climate change.

Historically, Andean cloud forest seedlings sprout higher in elevation during periods of global warming. However, an unprecedented rate of projected temperature gain in the region over the next century, 5 degrees Celsius, will have them going upslope faster than ever before, says Miles Silman, professor of Biology at Wake Forest University. Silman says plants are going to have to migrate around 3,000 feet to remain in equilibrium with the warming climate by 2100.

The problem with this is the trees can only go so far as higher elevation grasslands bar the path upslope. Unlike the cloud forest beneath it, Silman says the transition between trees and grassland, called an ecotone, is stationary over most of the landscape, and only barely moving in other places, even in the face of recorded temperature changes that should have moved it 200m higher. Silman says assuming no additional changes in climatic factors other than temperature, timberline would need to migrate around 900 meters in elevation to keep pace with the cloud forest beneath it. The results of their study show this would take 3,750 years in protected areas and 18,000 years in unprotected areas. Silman says scientists think that a combination of frequent human-set fires and cattle grazing in the grasslands, along with slow growth rates, likely explain a large part of it but aren't sure. What they do know, however, is that cloud forest trees can't go through or around the ecotone.

"Previous work we've done shows that the trees in the forest are migrating upwards, but this work shows the ecotone isn't," Silman says. "The ecotone presents a wall to species migration."

The Wake Forest team's research is the first to address rates of Andes timberline migration at high resolution. It consists of climate change projections based off computer modeling of photos and Quickbird satellite images of remote Cloud Forests in Peru's protected Manu National Park and unprotected surrounding areas. The photo data were collected by the United States Air Force's Aerial Survey teams during June, 1963, and digitized to 0.7 microns by the Peruvian Instituto Geographico Nacional.

The team's results will appeared in the Sept. 11, 2013 edition of the online journal PLOS ONE.

Lutz says current conservation strategies focus on mitigating human impact, essentially preventing human interference so that the cloud forest can evolve and grow as nature intended. He says a more hands on approach will be needed in the immediate future to protect the region from massive population loss.

"Intervention is a strategy conservationists seldom use in this ecosystem but it may be the only way to save it," he says. "Our next step is working with local, and international conservationists to come up a plan to help cloud forests keep moving upslope."

View the original article here

WHO urges governments to act on hepatitis threat

24 July 2013 | GENEVA - On World Hepatitis Day (28 July), WHO is urging governments to act against the five hepatitis viruses that can cause severe liver infections and lead to 1.4 million deaths every year. Some of these hepatitis viruses, most notably types B and C, can also lead to chronic and debilitating illnesses such as liver cancer and cirrhosis, and in addition to, loss of income and high medical expenses for hundreds of millions of people worldwide.

Viral hepatitis is referred to as a ‘silent epidemic’ because most persons do not realize that they are infected and, over decades, slowly progress to liver disease. Many countries are only now realizing the magnitude of the disease burden and devising ways to address it.

“The fact that many hepatitis B and C infections are silent, causing no symptoms until there is severe damage to the liver, points to the urgent need for universal access to immunization, screening, diagnosis and antiviral therapy,” says Dr Keiji Fukuda, WHO Assistant Director-General for Health Security and the Environment.

"Many of the measures needed to prevent the spread of viral hepatitis disease can be put in place right now, and doing so will offset the heavy economic costs of treating and hospitalizing patients in future."

Dr Sylvie Briand, Director, WHO Pandemic and Epidemic Diseases

This year, in the run up to World Hepatitis Day, the Organization is releasing its first-ever country hepatitis survey, covering 126 countries. The WHO "Global policy report on the prevention and control of viral hepatitis in WHO Member States" identifies successes as well as gaps at country level in the implementation of four priority areas. The priority areas are raising awareness, evidence-based data for action, prevention of transmission, and screening, care and treatment.

The findings show that 37% of the countries have national strategies for viral hepatitis, and more work is needed in treating hepatitis. It also highlights that while most of the countries (82%) have established hepatitis surveillance programmes, only half of them include the monitoring of chronic hepatitis B and C, which are responsible for most severe illnesses and deaths.

“Many of the measures needed to prevent the spread of viral hepatitis disease can be put in place right now, and doing so will offset the heavy economic costs of treating and hospitalizing patients in future,” says Dr Sylvie Briand, Director, Pandemic and Epidemic Diseases at WHO. “The findings underline the important work that is being done by governments to halt hepatitis through the implementation of WHO recommended policies and actions.”

The challenges posed by hepatitis were formally acknowledged by the World Health Assembly in 2010 when it adopted its first resolution on viral hepatitis, and called for a comprehensive approach to prevention and control. This has promoted a new era of awareness with more governments proactively working to address the disease. Reinforcing that call for action, WHO has been collaborating closely with countries and partners to build a strong global response. As a result, the new report notes, 38% of countries observe World Hepatitis Day (an annual event that began in 2010) with even more countries expected to mark the day this year.

In addition to collaborating closely with countries, WHO has been working on developing networks and mechanisms that can deliver results. The Organization is exploring with international funding agencies avenues that could allow hepatitis to be included in their current programme of activities. In June 2013, WHO launched the Global Hepatitis Network. One of its aims is to support countries with planning and implementation of viral hepatitis plans and programmes.

WHO is currently developing new hepatitis C screening, care and treatment guidelines, which will provide recommendations on seven key areas such as testing approaches; behavioural interventions (alcohol reduction); non-invasive assessment of liver fibrosis; and the selection of hepatitis C drug combinations.

”New, more effective medicines to prevent the progression of chronic hepatitis B and C are in the pipeline. However, these will be expensive and therapy will require monitoring with sophisticated laboratory tests. To cure and reduce the spread of these viruses, medicines must become more accessible,” says Dr Stefan Wiktor, Team lead of WHO’s Global Hepatitis Programme.

The complexity of hepatitis disease lies in the existence of different types of viruses. Hepatitis A and E are foodborne and waterborne infections which cause millions of cases of acute illness every year, sometimes with several months needed for a person to fully recover.

Hepatitis B, C, and D are spread by infected body fluids including blood, by sexual contact, mother-to-child transmission during birth, or by contaminated medical equipment. Hepatitis B and C have a greater health burden in terms of death because they can cause life-long infection (called chronic infection), which can lead to liver cirrhosis and cancer. In fact, chronic hepatitis is the leading cause of liver cirrhosis and cancer.

WHO-approved vaccines are available to prevent hepatitis A and B, while screening of blood donors, assuring clean needle and syringes, and condom use can prevent bloodborne and sexual transmission.

Hepatitis B can be prevented by reaching every child with immunization programmes that include hepatitis B vaccine. There is no vaccine for hepatitis C. In addition, infections can be prevented by protecting against mother-to-child transmission of the virus and ensuring the safety of blood, transfusion services, organ donation and injection practice (treatment can include antiviral medications if needed).Hepatitis A and E can be prevented by avoiding contaminated food and water; in addition, there is an effective WHO approved vaccine for hepatitis A. Hepatitis medicines are now included in the WHO Essential Medicines List, which Member States are encouraged to adopt. Essential medicines are selected based on disease prevalence, safety, efficacy, and comparative cost-effectiveness. The WHO Model List can be used by countries as a guide for the development of their own national list.

Mr Glenn Thomas
Communications Officer
WHO, Geneva
Telephone: +41 22 791 3983
Mobile: +41 79 509 0677
E-mail: thomasg@who.int

View the original article here