Advances in Soil Science: Volume 4

ISBN-13: 9781461386148 / Angielski / Miękka / 2011 / 226 str.

L. R. Ahuja; W. H. Gardner; D. R. Keeney

Opis

The world needs for food and fiber continue to increase. Population growth in the developing countries peaked at 2. 4 percent a year in 1965, and has fallen to about 2. 1 percent. However, in many developing countries almost half the people are under 15 years of age, poised to enter their productive and reproductive years. The challenges to produce enough food for this growing population will remain great. Even more challenging is growing the food in the areas of greatest need. Presently the world has great surpluses of food and fiber in some areas while there are devastating deficiencies in other areas. Economic conditions and the lack of suitable infrastructure for distribution all too often limit the alleviation of hunger even when there are adequate supplies, sometimes even within the country itself. World hunger can only be solved in the long run by increasing crop production in the areas where the population is growing most rapidly. This will require increased efforts of both the developed and developing countries. Much of the technology that is so successful for crop production in the developed countries cannot be utilized directly in the developing countries. Many of the principles, however, can and must be adapted to the conditions, both physical and economic, of the developing countries.

Spis treści

Early Soil Physics into the Mid-20th Century.- I. Introduction.- II. Early Beginnings.- III. The Renaissance to the 18th Century.- IV. The 18th to Early 19th Century.- V. The Birth of Soil Physics.- VI. The Rise of Soil Physics, First Decade.- VII. The Rise of Soil Physics, Second Decade.- VIII. The Beginning of the Modern Era.- IX. Acceleration of the Sciences Following World War II.- X The 1950s and Beyond.- References.- Nitrous Oxide Emission from Soils.- I. Introduction.- II. Processes Contributing to N2O Production.- III. Mechanisms of N2O Production in Soils.- IV. Control of N2O Emission from Soils.- V. Summary.- References.- Characterization and Modeling of Chemical Transfer to Runoff.- I. Introduction.- II. The Rainfall-Runoff-Soil Interaction.- III. Factors Influencing the Interaction.- IV. The Desorption of Adsorbed Chemicals.- V. Modeling the Transfer to Runoff.- VI. Transport from Partial Land-Area Applications—Buffer Strips.- VII. Shallow Subsurface Flow of Chemicals.- VIII. Summary, Applications, and Suggested Further Work.- Acknowledgments.- References.- Agronomical and Ecological Impact of Irrigation on Soil and Water Salinity.- I. Introduction.- II. Salinity and Secondary Salinization in Agriculture in Ancient Times.- III. The Main Aspects of Secondary Salinization and Alkalization.- IV. The Development of Irrigation as a Worldwide Method for Increasing Yields and the Consequent Extension of Secondary Salinization and Alkalization.- V. Combating Secondary Salinization and Alkalization.- VI. Conclusions.- References.