Terrestrial biomes have soil organic carbon (SOC) stocks determined by natural (e.g., vegetation cover, soil type, climate) and anthropogenic (e.g., soil and land-use management) factors. Thus, biome type is among the main control of SOC stocks. Historically, many terrestrial biomes in the United States of America (U.S.A.) had higher SOC stocks than the same regions store today, and this discrepancy has contributed to increases in atmospheric carbon dioxide (CO2) concentrations and soil degradation. However, losses of SOC stocks must be reduced and/or stocks increased by SOC sequestration as net increases in SOC stocks contribute to climate change adaptation and mitigation by storing atmospheric CO2 in protected and stabilized fractions for millennia. Increases in SOC stocks will also contribute to improved soil fertility and soil health. Therefore, the aim of this book is to collate, review and synthesize information on how SOC stocks differ among major terrestrial biomes of the U.S.A. Information on soil inorganic carbon (SIC) stocks for different terrestrial biomes of the U.S.A. will also be presented. The book deliberates options for increasing SOC stocks and enhancing SOC sequestration in terrestrial biomes by soil and land-use management practices. It concludes with an overview of terrestrial biomes of the U.S.A. where targeted soil and land-use management practices may result in the greatest increases in SOC stocks and enhancements in SOC sequestration.