Abstract 97-27058 Schladow Collaborative Research: Deep chlorophyll layers as export production zones in lake ecosystems: The importance of hydrodynamics and biological transport in the formation and maintenance of metalimnetic production In clear lakes and seas, much of the microscopic plant biomass occurs deep in the water column, in strata called deep-chlorophyll layers. Little is known about the processes that form these layers, nor their importance for fueling production of zooplankton and fish. Working in lakes of the Sawtooth Mountains of Idaho, the investigators will use the stable isotope lsN and water mass tracers to determine: (1) the sources of nutrients that support plant production in the deep chlorophyll layers; (2) the relative importance of physical mixing processes (e.g. wind, turbulence) and biological processes for moving nutrients between strata, and; (3) how much of the plant production in the deep water is transferred to the invertebrates and fish in different strata. This research will thus further our understanding of linkages between physical, chemical, and biological processes that govern production in aquatic food webs.
