ISSN:
1420-9055
Keywords:
Lake ecosystem
;
chl-a
;
phosphorus
;
nitrogen
;
river flow
;
thermocline
;
simulation model
;
multiple regression
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The management variables which primarily affect phytoplankton biomass (as chl-a) in Lake Mjøsa, Norway, are total phosphorus loading (TP) and the timing and volume of water through flow (by active storage reservoirs). The response of the lake to changes in these factors is studied using a simulation model of the lake ecosystem. Chl-a responses from both observed data and the simulated results are extracted by multiple regression. Results show that decreasing TP load decreases chl-a, but less at low TP levels (〈 10 mg TP · m−3). There is also a certain time period for peak river flow which gives the least yield of chl-a per unit TP. This time period occurs in early summer (i.e., around June 10) if the total phosphorus load is low, and later if the load is high. Both observations and simulation results show that a high water flow increases chl-a at low epilimnion depths (〈 15 m), but that the same high water flow decreases chl-a when epilmnion is deep.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00877062
