Geotimes Banner
Subscribe

Geotimes is now
    EARTH

Archives

Classifieds
Advertise
Customer Service
Geotimes Search

GeoMarketplace Link



EARTH magazine cover


  Geotimes - October 2007 - Trends and Innovations
TRENDS & INNOVATIONS

Europe’s Seas on the Brink of Disaster?
Nicole Branan

Image Caption and Credit Below
Josh Clark, www.globalmoxie.com
Part of the challenge for Europe’s seas includes new developments along the coastlines, such as at Portofino, Italy, along the Mediterranean, as shown here, thanks to growing prosperity across Europe.

Masked by the serenity of the turquoise lagoons along the Mediterranean coast and the stillness of the Baltic Sea’s glittering water, trouble is brewing beneath the surface of Europe’s seas, according to a recent, multinational study. Coastal development, overuse of fertilizers, chemical pollution and overfishing have pushed the Mediterranean, Baltic and Black seas, and the Northeast Atlantic into a “serious state of decline” the EU-funded study says. And unless these problems are addressed soon, the future of the seas’ biodiversity and resources looks bleak, the study warns.

Using data from hundreds of environmental and socioeconomic studies performed by marine scientists and economists over the past two to four decades, the team, composed of 28 research groups from 15 European countries, assembled a comprehensive picture of the four individual seas’ current situations. They fed the data into new models to predict which changes the seas might experience, simulating one “business-as-usual” scenario along with four alternatives, each reflecting different possible socioeconomic developments and policy decisions over the next two to three decades. “We saw serious damage in every sea,” says Laurence Mee of the University of Plymouth in the United Kingdom, who led the study. Furthermore, he says, “it is the combination of a number of pressures that humans have put on the land as well as on the seas that has led to this damage.”

Although previous research has documented the decline of Europe’s regional seas, this was one of the first projects to link the situation to European lifestyles, Mee says. Sweeping changes, such as the fall of the Communist bloc and the expansion of the European Union, have remodeled the continent’s economic and political landscape over the past two decades. But as these developments have led to more affluence, they have also left their mark on marine ecosystems. “For example, we have seen a huge increase in tourism and in the number of people who buy second homes at the sea,” Mee says. “That has put additional pressures on the coastal resources.”

And while a growing appetite for seafood has caused fish stocks in European waters to dwindle, land-based food consumption has wreaked havoc in the seas as well, says Jana Friedrich of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, and a co-author on the study. “Increasing wealth leads to higher consumption of animal protein,” she says. More intensive meat production requires more fertilizer to produce feed crops, resulting in higher runoff into the sea. This excess of nutrients contributes to hypoxia — low oxygen concentrations in the water column — creating suffocating conditions that can interfere with fish reproduction. The team, which presented their findings in June to the European Commission, found this problem to be particularly dire for enclosed waters such as the Baltic Sea, where harmful substances do not easily get flushed out.

“This is an innovative study that illustrates that all sectors of human activities need to be integrated into the management of the world’s oceans,” says Fan Tsao of the Marine Conservation Biology Institute in Bellevue, Wash. “Traditionally, fishery and other human activities have been managed in isolation from one another, but in reality they interact with each other.”

But it isn’t only modern beach houses and daily grilled salmon or steak dinners that can harm marine ecosystems. A separate study published May 3 in Quaternary Research that looks at the health of central Asia’s Aral Sea suggests that people helped inflict serious damage to the sea as early as about A.D. 400, when the White Huns, an Indo-European nomadic people, raged along the Amu Darya River and diverted it away from the Aral Sea, cutting off its water supply.

Like the Baltic, Black and Mediterranean seas, the Aral Sea has faced its share of human-induced hardships. Once the world’s fourth largest sea by surface area, the Aral has shrunk by two-thirds and has lost nearly nine-tenths of its volume through evaporation thanks to large-scale irrigation projects that began in the 1950s. By diverting water from two rivers that fed the sea, the Amu Darya and the Syr Darya, these projects not only caused the sea to shrink, but also initiated an acute ecological catastrophe. Steadily increasing salt concentrations wiped out 18 of the 20 fish species and killed hundreds of phytoplankton species (see Geotimes, August 2007).

Image Caption and Credit Below
Copyright Jana Friedrich
Algae is blooming at Varna Beach along the Black Sea in Bulgaria due to fertilizer runoff. The Black Sea, along with the Mediterranean, Baltic and Northeast Atlantic, are stressed, according to a new report on the state of Europe’s seas.

In the new study, Patrick Austin of the University College London in the United Kingdom and his colleagues examined diatoms — unicellular algae that are particularly sensitive to changes in the water’s chemical composition — trapped in sediment cores drilled from the bottom of the Aral Sea. The team reconstructed ancient water levels based on changes in the diatoms over time and found that periods of low water content coincided with periods of social upheaval: Lake levels dropped during the early 5th century when the White Huns diverted the Amu Darya, then recovered and dropped again in A.D. 1221, when Genghis Khan and his army marched into the region. Historical texts indicate that they flooded the city of Urgencj along the banks of the Amu Darya by destroying irrigation systems that had kept water flowing to the Aral Sea. Even though natural climate variations likely contributed to these periods of desiccation, human activity exacerbated them, Austin says.

Austin’s team’s research was part of a larger project that examined the Aral Sea’s ancient past and involved 11 research groups from several European and Asian countries. One of their goals was to highlight the interplay between climate variability and human activity to better understand climate dynamics in this part of the world, says Hedi Oberhänsli of the GeoForschungs Zentrum in Potsdam, Germany. “This study shows that the Aral Sea has seen worse hydrological conditions during the past 2,000 years than during Soviet and post-perestroika times when irrigation was pushed to a maximum,” she says.

Nonetheless, these more recent large-scale irrigation projects have led to the present ecological catastrophe, Oberhänsli says. Furthermore, while humans may have affected the Aral’s hydrological balance in the ancient past, they have never encroached on soil quality and human health like they have during the past 50 years with the rise of industrial agriculture, she points out. Even if rivers were diverted back into the Aral, the sea might not be able to recover, Austin cautions. “If global warming continues and we lose the glaciers and snowfields [feeding these rivers] then there won’t be any water to divert.”

Climate change may have enormous consequences for biodiversity and resources in Europe’s seas as well, Mee says. It’s important to take long-term effects into account, he adds, because problems that may have social consequences, such as drinking water shortages, may impose even greater pressure on marine ecosystems.

The results of all of these studies show that protection of marine environments is vitally important to halt further damage, Mee says. “This is a warning call, both for policymakers and for the people,” he says. “We need new policies and laws that protect our marine environments, but we also need to get the price right — if consumption of certain goods is costly for the environment then we need to incorporate that into the cost of the product.” Thus, he says, “people will either change their behavior or they will pay the price.”


Branan is a freelance writer living in Colorado.

Links:
www.globalmoxie.com 
"Salton Sea at a Crossroads," Geotimes, August 2007 

Back to top

 

Advertise in Geotimes


Geotimes Home | AGI Home | Information Services | Geoscience Education | Public Policy | Programs | Publications | Careers

© 2014 American Geological Institute. All rights reserved. Any copying, redistribution or retransmission of any of the contents of this service without the express written consent of the American Geological Institute is expressly prohibited. For all electronic copyright requests, visit: http://www.copyright.com/ccc/do/showConfigurator?WT.mc_id=PubLink