Hydrosphere, human impact

To this point, direct human impacts on the hydrosphere have remained restricted to the regional scale. Although they can still be important, particularly in terms of water supply, these direct manipulations of the hydrologic cycle are unlikely to affect the global water balance significantly. However, this is not to suggest that the global water cycle is immune to human influence its close ties to other physical and... 

Though the hydrosphere continues to operate in response to the same forces it always has, humans have had an unmistakable role in altering some of its balances. In general, these impacts have had relatively little effect on the overall global water balance, and there is little chance that direct manipulation of the hydrosphere will alter water storage and cycling on a global basis. 

This example demonstrates that differences between the impacts of particulate emissions are essentially smaller because of the high variability, inhomogeneity, and mobility of the atmosphere than in the discussed case study of the hydrosphere, which is an example of an environmental medium largely uninfluenced by human civilization. 

In an ecological sense, soils exist where the atmosphere, the hydrosphere, the geosphere, and the biosphere all converge. Thus, contaminants in soil can impact human health and the environment through a complex web of interactions. The sections below provide an introduction to three issues related to toxicology and soil - (1) the potential for soil... 

The next several chapters examine the factors that determine the speed and extent of chemical reactions kinetics (Chapter 14), equilibria (Chapters 15—17), thermodynamics (Chapter 19), and electrochemistry (Chapter 20). Also in this section is a chapter on environmental chemistry (Chapter 18), in which the concepts developed in preceding chapters are applied to a discussion of the atmosphere and hydrosphere. This chapter has been revised to focus more sharply on the impacts of human activities on Earth s water and atmosphere and on green chemistry. 

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