A New Dynamic Model for Suspended Particulate Matter (SPM) in Lakes

✍ Scribed by Lars Håkanson

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 487 KB
• Volume: 90
• Category: Article
• ISSN: 1434-2944
• DOI: 10.1002/iroh.200510790

✦ Synopsis

This paper presents a general, process-based model for suspended particulate matter (SPM) in lakes. The model has been tested using data from 7 lakes of different limnological character and shown to predict mean monthly SPM-concentrations in water very well. The model is based on processes regulating inflow and outflow, and internal processes. The separation between the surface-water layer and the deepwater layer is not done in the traditional manner by thermal stratification but by sedimentological criteria (by the wave base which regulates wind/wave-induced resuspension). The model calculates autochthonous production, resuspension, sedimentation, mixing, mineralization and retention of SPM. The new dynamic lake model is simple to apply in practice since all driving variables may be readily accessed from maps or regular monitoring programs. Modelled values have been compared to empirical data from lakes covering a relatively wide domain (catchment areas from 93 to 5250 km 2 , precipitation from 400 to 660 mm/yr, altitudes from -210 to 150 m.a.s.l., latitudes from 32 to 59 °N and continentalities from 200 to 1000 km from the ocean). When modelled values are compared to empirical data, the slope is almost perfect (1.02) and the r 2 -value is 0.89 for logarithmic values of SPM. This is very good given the fact that there are several simplifications in the model structure. It must, however, be stressed that there are only 7 cases of validation.