Modeling Lake Ladoga Zoobenthos and Studying Its Role in Phosphorus Exchange at the Water–Bed Interface

A zoobenthos submodel is included in an ecosystem model. The new model is used to assess the role of zoobenthos in the phosphorus exchange at the water–bed interface, in particular, the phosphorus cycle in the water body ecosystem is described more accurately. The calculated zoobenthos distribution over the bed of a lake can be used in modeling the lake ichthyocenoses.     

Identification of permeable zones based on the borehole observations of seismoacoustic emissions and helium concentrations

Measurements of seismoacoustic emissions in boreholes allow researchers to identify fault zones and zones of cracking and rock shattering. These zones are usually identified from the maximal values of seismoacoustic emission. However, the permeability of the identified zones cannot be estimated solely from the seismoacoustic emission data, especially in the case when seismoacoustic emission sources are located in isolation in the vicinity of a borehole. The experiments have shown that dynamically active permeable zones of tectonic failures can be identified based on joint measurements of seismoacoustic emissions and helium concentrations in fluid.     

Modeling climatic circulation of Onega Lake

The results of numerical modeling of Onega Lake climatic circulation are presented. The model used in this study was developed earlier and successfully applied to the reproduction of large-scale hydrodynamical processes in Ladoga Lake. The obtained results are of importance for the development of both models of nonreactive pollutant transport and ecosystem models of the water body. The developed model can be used to calculate currents and temperature fields for individual scenarios of external impacts on the water body, and the results of calculation of the climatic circulation can serve as initial approximations for scenario-based calculations.     

Estimation of potential changes in the ecosystem of Lake Ladoga in the 21st century under the impact of anthropogenic and climatic factors

The effect of potential climate changes on the ecosystem of Lake Ladoga at different levels of anthropogenic load is studied using mathematical models. The Lake Ladoga year-round circulation corresponding to potential climate changes in the lake catchment area is reproduced. The year-round regime of functioning of the lake ecosystem is reproduced using ecosystem models. The potential changes in the lake ecosystem due to changes in the phosphorus load within the limits observed in 1961–1983 are found to be more essential than those due to prognostic changes in climate.