The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
Saturation of soil with water, usually through irrigation, resulting in a condition under which most crop plants cannot grow. Although naturally wet soils are extremely common, human-caused waterlogging occurring on active croplands has created the most concern. Where fields are irrigated regularly, some means of drainage is usually necessary to let excess water escape, but if drainage is inadequate, water gradually accumulates, filling pore spaces in the soil. Once the oxygen in these pores is displaced by water, plant roots and soil microorganisms die. Waterlogging frequently occurs where flooding has been used. There are two main reasons for flooding: it is a simple, low-technology method of irrigation and in some cases it reduces harmful mineral concentrations in soils. Ideally, flood waters seep through the soil and into groundwater or stream channels, but in many agricultural regions, impermeable layers of clay block downward drainage so that irrigation water collects in the soil. Farmers who can afford it avoid this problem by installing some means of field drainage, such as perforated pipes below ground. However, the expense of this procedure is prohibitive in many regions.