Simple mass balance model for aquaculture area, based on the Vollenweider equation: dMw/dt = Min - sMw - Mout The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs for eutrophication assessment. Direct loading replaces input concentration Th
Environment Lakes And Reservoirs Eutrophication Aquaculture
Simple mass balance model for aquaculture area, based on the Vollenweider equation:

dMw/dt = Min - sMw - Mout

The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs for eutrophication assessment.

Direct loading replaces input concentration

The key uncertainty in these models is s, the loss of phosphorus to the sediment. Calculation of s, and the retention coefficient R used in the Dillon & Rigler model, was extensively analysed on the basis of existing literature, and the final equation used was from Canfield & Bachmann, 1981, for natural lakes.
Clone of QUASSA model
Alhambra
Insight diagram
Eutrophication
Workshop 5
徐韵昕
Simple mass balance model for aquaculture area, based on the Vollenweider equation: dMw/dt = Min - sMw - Mout The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs for eutrophication assessment. Direct loading replaces input concentration Th
Environment Lakes And Reservoirs Eutrophication Aquaculture
Simple mass balance model for aquaculture area, based on the Vollenweider equation:

dMw/dt = Min - sMw - Mout

The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs for eutrophication assessment.

Direct loading replaces input concentration

The key uncertainty in these models is s, the loss of phosphorus to the sediment. Calculation of s, and the retention coefficient R used in the Dillon & Rigler model, was extensively analysed on the basis of existing literature, and the final equation used was from Canfield & Bachmann, 1981, for natural lakes.
QUASSA model
Joao G. Ferreira
5
This stock and flow diagram provides a broad description of the key nutrient pathways (N and P) that exist in a dune-lake system subject to external loadings emanating from intensive agriculture.
Lake Nutrients Eutrophication Environment
This stock and flow diagram provides a broad description of the key nutrient pathways (N and P) that exist in a dune-lake system subject to external loadings emanating from intensive agriculture.
Clone of Stock and flow diagram of a dune lake (Working draft)
Miriam Rodrigues Da Costa
5 months ago
Simple mass balance model for fish grown in a tank (reactor): dO2/dt = O2in - sN - O2out The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs, for eutrophication assessment. In this adaptation, s (sigma) is the oxygen consumption of 1 fish in g
Environment Eutrophication Lakes And Reservoirs
Simple mass balance model for fish grown in a tank (reactor):

dO2/dt = O2in - sN - O2out

The model was first used in the 1960s to determine the phosphorus concentration in lakes and reservoirs, for eutrophication assessment.
In this adaptation, s (sigma) is the oxygen consumption of 1 fish in g ind-1 d-1 and N is the number of fish.

Aerator functionality was added to the model, oxygen input can be adjusted by changing the aerator power rating. This would be an extra term in the equation. The aerator model is taken from Boyd - in the real world, if DO in a pond or tank is above saturation, there would be no aeration to save mony.
Dissolved oxygen model
Joao G. Ferreira
4 days ago