Phosphorus effects in lakes

Here you can calculate the effect of phosphorus input into a lake. You can provide lake data yourself, or you may selecet a lake from the drop-down menu and get the lake data automatically set into the form below. However, for a number of lakes there are no data regarding average depth and volume. Also, the P input always has to be typed in by the user. Data regarding inflow and residence time are averages for the period 1991 - 2005. Please note that the model calculations are associated with rather large uncertainties.

Lake data   Annual P input  kg/yr   Annual water inflow  m3/yr   Average depth  m     Estimate the average depth from the max depth   m       Lake volume  m3     Estimate the lake volume from its surface area   m2       Calculation   Average residence time  yr   Phosphorus concentration in inflow, annual average  mg/l   Phosphorus concentration in the lake  mg/l   Concentration of chlorophyll a in the lake, annual average  ug/l   Secchi depth in the lake, annual average  m