ABSTRACT
This book is about environmental chemistry, the chemical processes, reactions, and conditions that occur in Earth’s environment. So, what is the environment? Earth’s environment may be considered as consisting of five closely related and interacting spheres: (1) the hydrosphere, consisting of water; (2) the atmosphere, composed mostly of air that envelopes Earth’s surface, the bulk of which lies in proximity to the surface; (3) the geosphere, which makes up the rock, mineral matter, and soil on or below Earth’s surface; (4) the anthrosphere, consisting of the many parts of Earth that have been made, modified, and operated by humans employing their ingenuity and technology; and (5) the biosphere, consisting of living organisms. These five spheres shown in Figure 1.1 make up the Earth System. 1 It is logical to discuss environmental chemistry on the basis of the five major environmental spheres, keeping in mind that they compose a total Earth System and interact strongly with each other including robust exchanges of matter and energy. Several chapters could be devoted to the five environmental spheres and the Earth System. However, since this is a book about environmental chemistry, it goes directly and specifically into environmental chemistry as it applies primarily to each of the spheres. But in order to discuss the environmental chemistry of any segment of the Earth System, it must take into account all the other segments; thus, each is defined and briefly described at the beginning within this introductory chapter.
