Sustaining the Hydrosphere

This chapter illustrates how elements and compounds are separated from the hydrosphere and crust of Earth, and put to use. The hydrosphere, which includes saltwater and freshwater above and below Earth s surface, must supply the water necessary to sustain hfe. The soluble salts in the oceans are a commercial source of magnesium, bromine, and sodium chloride, which is not only table salt but also an essential chemical raw material. 

Water is one of the most abundant chemical components on Earth. The hydrosphere consists of more than 90% of water 50%-90% of the gas in the atmosphere is water vapor the lithosphere (the Earth s crust) contains, on average, about 15% water and living organisms on our planet typically contain 50%-90% water. Because of its ubiquity, water may be considered as very normal and common. Yet, from a physical-chemical point of view, water is a unique extraordinary substance. By virtue of its unique properties, water is the medium, par excellence, in which life has evolved and is sustained. To be more precise, in living organisms water fulfills the following functions ... 

Fundamentals of Environmental and Toxicological Chemistry Sustainable Science, Fourth Edition covers university-level environmental chemistry, with toxicological chemistry integrated throughout the book. This new edition of a bestseller provides an updated text with an increased emphasis on sustainability and green chemistry. It is organized based on the five spheres of Earth s environment (1) the hydrosphere (water), (2) the atmosphere (air), (3) the geosphere (solid Earth), (4) the biosphere (life), and (5) the anthrosphere (the part of the environment made and used by humans). 

The first chapter defines environmental chemistry and each of the five environmental spheres. The second chapter presents the basics of toxicological chemistry and its relationship to environmental chemistry. Subsequent chapters are grouped by sphere, beginning with the hydrosphere and its environmental chemistry, water pollution, sustainability, and water as nature s most renewable resource. Chapters then describe the atmosphere, its structure and importance for protecting life on Earth, air pollutants, and the sustainability of atmospheric quality. The author explains the nature of the geosphere and discusses soil for growing food as well as geosphere sustainability. He also describes the biosphere and its sustainability. 

The next three chapters involve the hydrosphere. Chapter 3 explains the nature of the hydrosphere and the major aspects of its environmental chemistry. Chapter 4 deals specifically with water pollution and includes some aspects of the toxicological chemistry of the hydrosphere. Chapter 5 addresses the sustainability of the hydrosphere and water as nature s most renewable resource. 

Soils are multicomponent, multiphase, open systems that sustain a myriad of interconnected chemical reactions, including those involving the soil biota. The multiphase nature of soil derives from its being a porous material whose void spaces contain air and aqueous solution. The solid matrix (which itself is multiphase), soil air, and soil solution—each is a mixture of reactive chemical compounds—hence the multicomponent nature of soil. Transformations among these compounds can be driven by flows of matter and energy to and from the vicinal atmosphere, biosphere, and hydrosphere. These external flows, as well as the chemical composition of soil, vary in both space and time over a broad range of scales. 

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