Cycling of nutrients, such as Carbon (C) and Nitrogen (N), is one of the most important soil functions and is strongly related to the composition of the soil microbial community. However, soil is increasingly under environmental pressures that threaten its ecological functions and sustainability. To maintain soil functional sustainability, it is important to understand how soil withstands environmental stresses (subsequently referred to as resistance) and recovers from stresses (subsequently referred to as resilience). This study focused on the resistance and resilience of C and N processes and the underpinning microbial communities to a persistent Cu stress or a transient heat stress. The main advances and novel findings of this thesis are: (1) C mineralization is more resistant and resilient than ammonia oxidation and denitrification, and thus the combination of C and N processes are more informative than measuring a single process to interpret the overall resistance and resilience; (2) microbial composition and microbial physiological evolution play important roles in affecting resistance and resilience; (3) soil physico-chemical properties (e.g. organic matter, soil water and soil pH) are critically important in conferring resistance and resilience. The outcome of this study advances the understanding of the mechanisms of soil resistance and resilience of C and N cycling to environmental changes. The results generated here are an essential step for improving soil sustainability and promoting agricultural productivity under future environmental challenges.

Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisors: Karl E. Wommack, Dept. of Plant & Soil Sciences, University of Delaware; Mark Radosevich, Dept. of Biosystems Engineering and Soil Science, University of Tennessee. Includes bibliographical references.

Thesis (M.S.)--Oregon State University, 1981. / Typescript (photocopy). Includes bibliographical references (leaves 125-132). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1981. / Typescript (photocopy). Includes bibliographical references (leaves 105-113). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xix, 246 p.; also includes graphics. Includes abstract and vita. Advisor: William E. Wolfe, Dept. of Civil Engineering. Includes bibliographical references (p. 137-142).

Thesis (M.S. - Agricultural Chemistry and Soils)--University of Arizona, 1971. / Includes bibliographical references.

Thesis (M.S. - Soils, Water and Engineering)--University of Arizona. / Includes bibliographical references.

Thesis (Ph. D. - Watershed Management)--University of Arizona. / Includes bibliographical references.

Thesis (M.S. - Soils, Water and Engineering)--University of Arizona, 1985. / Includes bibliographical references (leaves 46-47).