Ephemerals


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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ephemerals

 

(in Russian, ingredienty), species of plants that temporarily become part of plant communities in arid regions (dry steppes, semideserts). Ephemerals develop episodically: they may be represented in large numbers in wet years. Some ephemerals use excess moisture in early spring, others in late autumn, when components or species that constitute the permanent base of the plant cover (prevailers) are just beginning to grow or finishing growing. In dry years ephemerals may not develop altogether, surviving through unfavorable times in the form of seeds that retain their germinating power for a long time. Biennials develop leaf rosettes in late autumn and blossom and bear fruit in early spring. Typical ephemerals include bristly brome, hop clover, common whitlow grass, and perfoliate pepperwort. The term ingredienty was proposed by J. K. Paczoski in 1910 for the southern Russian steppes.


Ephemerals

 

a group of annual herbs that complete a full cycle of development in a very short period of time. Ephemerals have fall-winter-spring vegetative cycles that last from six weeks (Gamanthus gamocarpus, orache) to eight months (desert bos-tryx, desert madwort, Ceratocephala falcata). They constitute a large part of the vegetative cover of deserts, semideserts (57–63 percent of the species composition), and some steppe regions. Ephemerals are noted for their exceptional adaptability to changes in the environment.

Early ephemerals retain a mesomorphic leaf structure; later ones have a xeromorphic structure that is expressed in various degrees. The seeds of vernal ephemerals germinate in the spring; those of winter forms, in the fall. The dormant period of the seeds and fruits coincides approximately with the summer season. The seeds of grasses and legumes remain viable for as many as seven years; those of other ephemerals, for no more than three years.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
(2) At right are bluebells, one of the spring ephemerals at the garden.
Quietly peeking through the last remnants of snow and ice that remain in our backyards, the buds of ephemeral flowers take advantage of the abundant amount of sunshine they receive when there are no leaves or other foliage to block the light's path.
his or her favorite ephemeral. Marketing and public relations director Debra Strick enjoys the Shooting Star (Dodecatheon meadia), which consists of magenta, white and lilac flowers with lobes that bend backward to resemble falling stars.
A stepwise regression analysis (16) was employed to determine how topographic characteristics (independent variables) at a given location influenced local occurrence or severity of ephemeral channel development (dependent variable).
This suggests that although drought reduced ephemeral erosion during 1988 and 1989, relative size and spatial information provided by channel measurements during 1989 were realistic and adequate for analyses of associated topographic relationships.
The conventional ephemeral erosion model predicts that the surface horizon of eroded soils becomes more similar to that of the subsoil as erosion proceeds.
It is not clear whether a cause-effect relationship exists between strongly developed ephemeral channels and increasing sand content with depth.
Lots of our spring ephemerals rely on ants to disperse their seeds, including violets, trout lily, blood root, Trillium, wild ginger, and Dutchman's breeches.
In only takes a few seconds to find that the Times used the word ephemeral 731 times since 1980, but has used ephemerA only 186 times, a fact thet probably won't escape the attention of the equal-ephemera militants.
For example, if I ask the computer to search for each instance where the Times mentions ephemeral within five words of baseball, I get a story that discusses the general managership of the Yankees, "...that most ephemeral of all baseball jobs."
As anyone might have guessed, there's an East-coast-liberal-establishment bias toward words ephemeral: the New York Times has 48 percent more usages since 1985 than does Los Angeles Times, despite the fact that the Los Angeles paper contain slightly more editorial copy than the Times.
The Anchorage Dails News and the Soviet news agency TASS each could muster only a single ephemeral.