Water Quality, Soil Chemistry, and Ecosystem Responses to P Dosing

The purpose of this chapter is to characterize the water and soil chemistry with a strong emphasis on phosphorus dynamics and trends. Information on water depth variations, diel oxygen, and pH provides supporting information for determining both P responses and effects. Ecosystem responses to P additions are presented via the P effects on diel oxygen production, respiration, gross primary productivity (GPP), and community respiration. In addition, measurements of alkaline phosphatase were done to assess P limitations in the channels and to assure that P additions affected the entire channel. Individual plant, algal, macroinvertebrate, and fish responses are presented in later chapters in this volume (Chaps. 16, 18, and 19). The influence of P on decomposition is given in Chap. 17. The assessment of a P threshold is covered in detail in the modeling section of Chap. 25.