Structurally dynamic models. In structurally dynamic models, the parameters are constantly varied to account for adaptation and shifts in the species composition (Xxxxx et al., 2010). These models are more popular in fundamental science than in applied science, as they aim at development of theory of complex lake ecosystems rather than making realistic predictions to support lake ecosystem management (Mooij et al., 2010). In general, structurally dynamic models can be valuable to answer questions related to specific biological processes, but should be used with great caution when predicting ecological effects of changing environmental conditions, e.g. due to climate change or measures to restore the lake ecosystem. There are different types of structurally dynamic models. Minimal dynamic models are very simple structurally dynamic models and have been mostly applied to study predator – prey interactions (Xxxxxxxx et al., 1997). Individual based models usually focus on the population structure (e.g. size, weight, age) of a few ecological groups (especially macrophytes, fish). For modelling large populations in lakes, it is generally too computationally demanding to model all individuals seperately. Therefore super-individual models have been developed. In the super- individual approach each individual has an extra property, namely the number of individuals that it represents. This approach has been applied in macrophyte model Charisma (Xxx Xxx et al, 2003), the fish model Piscator (Xxx Xxx et al., 2002) and the zebra mussel model Xxxxxxxxx (Xxx Xxx et al., 2008). Charisma describes the seasonal cycle of macrophytes in shallow lakes. It is especially detailed in the description of photosynthesis, and can model self shading and shading among different species. Piscator has eight interacting fish species, three types of fishery, piscivorous birds and a simple representation of the fish food. The model can include size differences among year classes by defining different super individuals with slightly different growth rates. Dreissena model describes the growths of the zebra mussels (Dreissena polymorpha). The model is spatially explicit and predicts length frequency distributions of zebra mussels. Another type of structurally dynamic model is based on the Dynamic Energy Budget theory (Xxxxxxxx, 2012). Dynamic Energy Budgets (XXX) models are linking physiological processes of individual organisms such as ingestion, assimilation, respiration, growth and reproduction, in a framework of ecos...
