ABSTRACT
This chapter focuses on biogeochemical processes that regulate the exchange of solutes and other chemical constituents between soil, water, and air in wetlands. Geologists working in aquatic ecosystems refer to some of these exchange processes as diagenesis, which is de ned as the sum total of processes that bring changes in a sediment subsequent to particulate matter deposition and exchange processes between sediment and water. Soil scientists working in terrestrial ecosystems refer to pedogenesis as the sum total of processes and factors that in uence soil formation. As wetlands possess the characteristics of both terrestrial and aquatic systems, both diagenetic and pedogenic processes in uence the forming of wetland soils and associated exchange processes between soil and water. Many of the transport processes discussed in this chapter are applicable to both wetlands and aquatic systems, such as shallow lakes and streams. For processes with limited information on wetland ecosystems, examples from select aquatic systems will be used to demonstrate basic concepts related to exchange processes. Much of the basic principles presented in this chapter follow from two textbooks (Lerman, 1979; Berner, 1980); the reader should refer to these for an excellent overview on geochemical processes and sediment-water interactions in aquatic systems.
