Biodiversity & Conservation

Can Ocean Desalination Solve the World's Water Shortage?

Fresh water scarcity is already posing major problems for more than a billion people around the world, mostly in arid developing countries. The World Health Organization predicts that by mid-century, four billion of us—nearly two-thirds of the world’s present population—will face severe fresh water shortages.

Population Growth Drives Quest for Water by Desalination

With human population expected to balloon another 50 percent by 2050, resource managers are increasingly looking to alternative scenarios for quenching the world's growing thirst. Desalination—a process whereby highly pressurized ocean water is pushed through tiny membrane filters and distilled into drinking water—is being held forth by some as one of the most promising solutions to the problem.

But critics point out it doesn't come without its economic and environmental costs.

Costs and Environmental Impact of Desalination

According to the non-profit Food & Water Watch, desalinated ocean water is the most expensive form of fresh water out there, given the infrastructure costs of collecting, distilling and distributing it. The group reports that, in the U.S., desalinated water costs at least five times as much to harvest as other sources of fresh water. Similar high costs are a big hurdle to desalination efforts in poor countries as well, where limited funds are already stretched too thin.

On the environmental front, widespread desalination could take a heavy toll on ocean biodiversity. "Ocean water is filled with living creatures, and most of them are lost in the process of desalination," says Sylvia Earle, one of the world's foremost marine biologists and a National Geographic Explorer-in-Residence. “Most are microbial, but intake pipes to desalination plants also take up the larvae of a cross section of life in the sea, as well as some fairly large organisms…part of the hidden cost of doing business,” she says.

Earle also points out that the very salty residue left over from desalination must be disposed of properly, not just dumped back into the sea. Food & Water Watch concurs, warning that coastal areas already battered by urban and agricultural run-off can ill afford to absorb tons of concentrated saltwater sludge.

Is Desalination the Best Option?

Food & Water Watch advocates instead for better fresh water management practices. "Ocean desalination hides the growing water supply problem instead of focusing on water management and lowering water usage," the group reports, citing a recent study which found that California can meet its water needs for the next 30 years by implementing cost-effective urban water conservation. Desalination is "an expensive, speculative supply option that will drain resources away from more practical solutions," the group says.

Despite such arguments, the practice is becoming more common. Ted Levin of the Natural Resources Defense Council says that more than 12,000 desalination plants already supply fresh water in 120 nations, mostly in the Middle East and Caribbean. And analysts expect the worldwide market for desalinated water to grow significantly over the coming decades. Environmental advocates may just have to settle for pushing to "green" the practice as much as possible in lieu of eliminating it altogether.

What Good are Greenbelts?

The term “greenbelt” refers to any area of undeveloped natural land that has been set aside near urban or developed land to provide open space, offer light recreational opportunities or contain development. And, yes, the natural greenbelts along areas of Southeast Asia’s coastlines, including the region’s mangrove forests, served as buffers and helped to prevent even greater loss of life from the December 2004 tsunami.

The Importance of Greenbelts in Urban Areas

Greenbelts in and around urban areas have probably not saved any lives, but they are important nonetheless to the ecological health of any given region.

The various plants and trees in greenbelts serve as organic sponges for various forms of pollution, and as storehouses of carbon dioxide to help offset global warming.

“Trees are an important part of the city infrastructure,” says Gary Moll of American Forests. Because of the many benefits trees provide to cities, Moll likes to refer to them as the “ultimate urban multi-taskers.”

Urban Greenbelts Provide Links to Nature

Greenbelts are also important to help urban dwellers feel more connected to nature. Dr. S.C. Sharma of the Council of Scientific and Industrial Research in India believes that all cities should “earmark certain areas for the development of greenbelts [to] bring life and color to the concrete jungle and [a] healthy environment to the urbanities.”

Greenbelts Help to Limit Urban Sprawl

Greenbelts are also important in efforts to limit sprawl, which is the tendency for cities to spread out and encroach on rural lands and wildlife habitat. Three U.S. states—Oregon, Washington and Tennessee—require their largest cities to establish so-called “urban growth boundaries” to limit sprawl through the establishment of planned greenbelts. Meanwhile, the cities of Minneapolis, Virginia Beach, Miami and Anchorage have created urban growth boundaries on their own. In California’s Bay Area, the non-profit Greenbelt Alliance has successfully lobbied for the establishment of 21 urban growth boundaries across four counties surrounding the city of San Francisco.

Greenbelts Around the World

The concept has also caught on in Canada, with the cities of Ottawa, Toronto and Vancouver adopting similar mandates for the creation of greenbelts to combat sprawl. Urban greenbelts can also be found in and around larger cities in Australia, New Zealand, Sweden and the United Kingdom.

Are Greenbelts Essential to World Peace?

The greenbelt concept has even spread to rural areas, such as those in East Africa. Womens’ rights and environmental activist Wangari Maathai launched the Green Belt Movement in Kenya in 1977 as a grassroots tree-planting program to address the challenges of deforestation, soil erosion and lack of water in her home country. To date, her organization has overseen the planting of 40 million trees across Africa.

In 2004 Maathai was the first environmentalist to be awarded the prestigious Nobel Peace Prize. Why peace? “There can be no peace without equitable development, and there can be no development without sustainable management of the environment in a democratic and peaceful space,” said Maathai in her Nobel acceptance speech.

Reduce Human Beings by 90 Percent to Solve Environmental Woes, Says Scientist

A professor at the University of Texas at Austin believes planet Earth would be better off if Mother Nature simply killed off 90 percent of the human population—and he predicts that is exactly what will happen in the not-too-distant future.

According to Professor Eric Pianka, a specialist in herpetology and evolutionary ecology who was named the 2006 Distinguished Texas Scientist by the Texas Academy of Science, human beings have strained Earth’s natural resources to the breaking point, leaving the planet “parched.”

Pianka believes the solution to this crisis is to eliminate the cause, by decreasing the number of human beings living on Earth from 6.5 billion to around 700 million—a 90 percent reduction.

Pianka is convinced that Nature eventually will exterminate the majority of humans through widespread disease or other effects of global warming—and he seems delighted at the prospect.

“This is really an exciting time,” he told the audience at a recent presentation of his “doomsday talk,” which is designed to raise awareness about the dangers of overpopulation and excess demands on the environment. “Every one of you who gets to survive has to bury nine.”

Not everyone is quite so gleeful as Pianka at the prospect of widespread death and destruction. Some critics have called Pianka a “loose cannon” and have slammed him for advocating what they consider “worldwide genocide.” According to a Wikipedia article about Pianka, a report to the Department of Homeland Security that he was “fomenting bioterrorism” led to an interview with the FBI.

Why are Honeybees Disappearing?

Kids everywhere may revel in the fact that bees are no longer stinging them as frequently on playgrounds and in backyards, but the decline in honeybee populations in the U.S. and elsewhere signals a major environmental imbalance that could have far-reaching implications for our agricultural food supply.

The Importance of Honeybees

Brought here from Europe in the 1600s, honeybees have become widespread across North America and are bred commercially for their abilities to produce honey and pollinate crops—90 different farm-grown foods, including many fruits and nuts, depend on honeybees.

But in recent years honeybee populations across the continent have plummeted by as much as 70 percent, and biologists are still scratching their heads as to why and what to do about the problem which they have termed “colony collapse disorder” (CCD).

Chemicals May Be Killing the Honeybees

Many believe that our increasing use of chemical pesticides and herbicides, which honeybees ingest during their daily pollination rounds, are largely to blame. Commercial beehives are also subjected to direct chemical fumigation at regular intervals to ward off destructive mites. Another leading suspect is genetically modified crops, which may generate pollen with compromised nutritional value.

It may be that the build-up of both synthetic chemicals and genetically modified crop pollen has reached a “tipping point,” stressing bee populations to the point of collapse. Lending credence to this theory is that organic bee colonies, where chemicals and genetically modified crops are avoided, are not experiencing the same kind of catastrophic collapses, according to the non-profit Organic Consumers Association.

Radiation May Push Honeybees Off Course

Bee populations may also be vulnerable to other factors, such as the recent increase in atmospheric electromagnetic radiation as a result of growing numbers of cell phones and wireless communication towers. The increased radiation given off by such devices may interfere with bees’ ability to navigate. A small study at Germany’s Landau University found that bees would not return to their hives when mobile phones were placed nearby. Further research is currently underway in the U.S. to determine the extent of such radiation-related phenomena on bees and other insect populations.

Global Warming May Be Partly to Blame for Honeybee Deaths

Biologists also wonder if global warming may be exaggerating the growth rates of pathogens such as the mites, viruses and fungi that are known to take their toll on bee colonies. The unusual hot-and-cold winter weather fluctuations in recent years, also blamed on global warming, may also be wreaking havoc on bee populations accustomed to more consistent seasonal weather patterns.

Scientists Still Searching for Cause of Honeybee Colony Collapse Disorder

A recent gathering of leading bee biologists yielded no consensus, but most agree that a combination of factors is likely to blame. “We’re going to see a lot of money poured into this problem,” says University of Maryland entomologist Galen Dively, one of the nation’s leading bee researchers. He reports that the federal government plans an allocation of $80 million to fund research in connection with CCD. “What we’re looking for,” Dively says, “is some commonality which can lead us to a cause.”