This book highlights recent advances in the discipline of biogeochemistry that have directly resulted from the development of critical zone (CZ) science. The earth's critical zone (CZ) is defined from the weathering front and lowest extent of freely circulating groundwater up through the regolith and to the top of the vegetative canopy. The structure and function of the CZ is shaped through tectonic, lithologic, hydrologic, climatic, and biological processes and is the result of processes occurring at multiple time scales from eons to seconds. The CZ is an open system in which energy and matter are both transported and transformed. Critical zone science provides a novel and unifying framework to consider those coupled interactions that control biogeochemical cycles and fluxes of energy and matter that are critical to sustaining a habitable planet. Biogeochemical processes are at the heart of energy and matter fluxes through ecosystems and watersheds. They control the quantity and quality of carbon and nutrients available for living organisms, control the retention and export of nutrients affecting water quality and soil fertility, and influence the ability for ecosystems to sequester carbon. As the term implies, biogeochemical cycles, and the rates at which they occur, result from the interaction of biological, chemical, and physical processes. However, finding a unifying framework by which to study these interactions is challenging, and the different components of bio-geo-chemistry are often studied in isolation. The authors provide both reviews and original research contributions with the requirement that the chapters incorporate a CZ framework to test biogeochemical theory and/or develop new and robust predictive models regarding elemental cycles. The book demonstrates how the CZ framework provides novel insights into biogeochemistry.

Principles and Dynamics of the Critical Zone is an invaluable resource for undergraduate and graduate courses and an essential tool for researchers developing cutting-edge proposals. It provides a process-based description of the Critical Zone, a place that The National Research Council (2001) defines as the "heterogeneous, near surface environment in which complex interactions involving rock, soil, water, air, and living organisms regulate the natural habitat and determine the availability of life-sustaining resources." This text provides a summary of Critical Zone research and outcomes from the NSF funded Critical Zone Observatories, providing a process-based description of the Critical Zone in a wide range of environments with a specific focus on the important linkages that exist amongst the processes in each zone. This book will be useful to all scientists and students conducting research on the Critical Zone within and outside the Critical Zone Observatory Network, as well as scientists and students in the geosciences – atmosphere, geomorphology, geology and pedology. - The first text to address the principles and concepts of the Critical Zone - A comprehensive approach to the processes responsible for the development and structure of the Critical Zone in a number of environments - An essential tool for undergraduate and graduate students, and researchers developing cutting-edge proposals