Featured Research

from universities, journals, and other organizations

Dual nature of dew: Researcher measures the effect of dew on desert plants

Date:
October 4, 2010
Source:
American Friends of Tel Aviv University
Summary:
Dew is often celebrated as a bringer of life. Now, a researcher in Israel has examined the effects of dew in the Eastern Mediterranean region and says that dew serves as an important water source for plant life.

Dew on plant.
Credit: iStockphoto/K Kurhan

When the scientific and traditional worlds collide, they do so in the most surprising ways. Classical meteorological and plant science has, in the last century, assumed that dew can negatively affects plant life, leading to rot and fungus. But in some traditions, dew is most welcomed as an important source of vegetative and plant life, celebrated in poetry and prayer.

Now Prof. Pinhas Alpert of Tel Aviv University's Department of Geophysics and Planetary Sciences has developed an explanation for the perplexing paradox with his colleagues. According to scientific literature, he says, dew that accumulates through the night has a negative effect on vegetation and fruits because it creates a "spongy" effect. But in a recent issue of the Water Resources Journal, Prof. Alpert demonstrates that dew is an important water source for plant life in climates such as those in the Eastern Mediterranean and parts of the U.S. Great Basin Desert.

"Semi-arid zones are dry for over half the year," he explains. "Dew is therefore an important source of moisture in the air. It surrounds the plant leaves nearly every morning for approximately two to three hours past sunrise." This finding, he says, explains why dew is such an important part of certain traditions.

Creating the ideal conditions for growth

A plant's growth is based on photosynthesis, employing stomata, the small openings in vegetation and fruit leaves that absorb carbon dioxide. The combination of water, carbon dioxide in the air and sunlight help a plant to produce sugars which allow it to grow. In temperate zones, most of a plant's growth occurs in the middle of the day, when the most sunlight is available.

But there are climatic influences as well. According to Prof. Alpert, plants in a semi-arid zone close these stomatic openings in the midday as a defence mechanism, to avoid losing moisture, or in other words water, when the weather is at its driest. When this happens, photosynthesis and plant growth cannot take place.

For these reasons, the early-morning hours -- and not those of midday -- are the period of maximum growth for plants in the Eastern Mediterranean region, Prof. Alpert says. And it's all due to the dew. "In the early morning, dew surrounds the leaves of a plant with moisture, and the plant does not close its stomata. Therefore, it can grow."

Life-giving dew

In order to research the effect of dew on plant life, Prof. Alpert and his fellow scientists studied the interaction between the leaves of a plant and the air. They measured how much moisture departs from the leaves and how much carbon dioxide enters them at various times of the day.

These findings explain a very old paradox, says Prof. Alpert. Despite its negative reputation in other climates, dew has been idealized in the Eastern Mediterranean for its ability to help fruits and vegetables grow in a dry and inhospitable region.


Story Source:

The above story is based on materials provided by American Friends of Tel Aviv University. Note: Materials may be edited for content and length.


Cite This Page:

American Friends of Tel Aviv University. "Dual nature of dew: Researcher measures the effect of dew on desert plants." ScienceDaily. ScienceDaily, 4 October 2010. <www.sciencedaily.com/releases/2010/09/100928122608.htm>.
American Friends of Tel Aviv University. (2010, October 4). Dual nature of dew: Researcher measures the effect of dew on desert plants. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2010/09/100928122608.htm
American Friends of Tel Aviv University. "Dual nature of dew: Researcher measures the effect of dew on desert plants." ScienceDaily. www.sciencedaily.com/releases/2010/09/100928122608.htm (accessed April 16, 2014).

Share This



More Plants & Animals News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. Video provided by Newsy
Powered by NewsLook.com
In Washington, a Push to Sterilize Stray Cats

In Washington, a Push to Sterilize Stray Cats

AFP (Apr. 14, 2014) To curb the growing numbers of feral cats in the US capital, the Washington Humane Society is encouraging residents to set traps and bring the animals to a sterilization clinic, after which they are released.. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
After Attack, Officials Kill 5 Bears in Florida

After Attack, Officials Kill 5 Bears in Florida

AP (Apr. 14, 2014) Florida wildlife officials say they have killed five bears following an attack on a woman in a suburban subdivision in central Florida. Forty-five year-old Terri Frana was attacked by a large bear in her driveway Saturday. (April 14) Video provided by AP
Powered by NewsLook.com
Uruguay Opens Its First Cannabis Library

Uruguay Opens Its First Cannabis Library

AFP (Apr. 13, 2014) Uruguay opened its first Cannabis Library in Montevideo on Saturday, where people can come and read books on cannabis or take classes on how to grow the plant or even how to cook with it. Duration: 01:20 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins