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Ukrainian energy sector depends on the fossil fuels, as long as the indicator of energy intensity is one of the highest in the world. Despite the fact that Ukraine has a significant potential of energy resources, it is an energy-deficient country. The government policy is aimed on the support of renewable energy, providing certain instruments in order to increase investment in this sphere. Moreover, there are different programs stimulating the improvement of energy efficiency. This paper also represents a first attempt to analyze the factors influencing the final energy consumption of economic entities of Ukraine using the logarithmic mean Divisia index (LDMI) method. The conducted analysis shows that the reduction of final energy consumption is caused mainly by decrease of energy intensity indicator. This information can be useful for the enterprises' management and the government in order to take further actions in energy efficiency improvement and transition towards renewable energy sources. [ABSTRACT FROM AUTHOR]

Aquatic sediments accumulate heavy metals that are discharged into the environment. This study investigates possible water quality changes due to release of heavy metals such as Cd, Ni, Zn and Pb into the water column during dredging of anoxic sediments in the Old Harbour of Montreal. An environmental impact assessment of the sediment removal requires estimating the speciation of heavy metals in the water column with and without the solid phase. Chemical equilibria in the St. Lawrence River water are calculated using the program EQUILIB from the software FACT. Results show that the water is oversaturated with respect to CaMg(CO[sub 3])[sub 2] and Fe(OH)[sub 3]. It is speculated that (ZnO)(Fe[sub 2]O[sub 3]) and (NiO)(Fe[sub 2]O[sub 3]) control the solubility of Zn and Ni in the water. The speciation of heavy metals in pore water of anoxic sediments is calculated, taking into account that the corresponding sulfides are solid phases and control their solubility. The impact of various scenarios on the area of concern is reviewed from an ecotoxicological perspective. Dredging might change the redox and acid-base conditions in the water column. Dredging can lead to an increase in the concentration of heavy metals in the water column and a change of metal speciation, but its impact will be less visible if the sediments contain high levels of calcium acting as a buffer. [ABSTRACT FROM AUTHOR]