Sources, concentrations and characteristics of organic matter in softwater lakes and streams of the Swedish forest region

Types of organic matter in natural waters of the Swedish boreal forest zone were quantified and characterized, with particular attention to the impact of humic matter and the distribution of different phosphorus forms. The study area embraced 18 forest lakes showing a wide variety of trophic states. Methods commonly used to measure the concentration of organic matter were compared. Estimates of organic carbon based on simple analytical procedures were also obtained. Organic matter was classified according to origin, physical state (dissolved or particulate) and nutrient content (carbon/phosphorus ratio). There are 30 references.