The use of mass balance investigations in the study of the biogeochemical cycle of sulfur

摘要: The use of mass balances in the investigation biogeochemical cycle sulfur is reviewed for three systems: I) upland catchments, 2) wetlands, and 3) lakes. In major inputs are via wet dry atmospheric deposition, whereas outputs or losses occur primarily through volatilization and/or runoff. addition, may be stored vegetation forest floor. wetlands (particularly peatlands), a large proportion derived from surface groundwater originating system. Because fluctuating water table they can act as source sink sulfate, depending on redox conditions. Wetlands, therefore, significantly affect input-output budgets most lakes, only small portion sulfate input retained, (i.e. not lost lake outflow), indicating that there an excess relative to biological needs. Seepage lakes exceptions this generalization. Although reactivity many low, levels, especially regions receiving substantial high enough reduced results in-lake alkalinity production; fact, cases, production reduction greater than resulting other processes but external sources (the catchment) well. importance balance investigations elucidating cycling stressed need additional studies whole-system basis stressed.