Population changes are a minor factor in CO2 emissions. The chart below shows that you can have an increase in population and a decrease in CO2 emissions. The bigger factors are GDP increases and the economy.
Like Russia, Ukraine has seen a greater reduction in CO2 emissions since 1990 than laid out in the Kyoto Protocol - the reason being the collapse of national industry in the 1990s. The result was such a dramatic drop in emissions that in recent years, the country saw a welcome boost to state funds received from the trade of carbon emission quotas.
Long-Term Trend in Global CO2 Emissions (2011, 42 pages, EU Commission)
Fossil fuel combustion accounts for about 90% of total global CO2 emissions excluding forest fires and woodfuel use. As the global economy rebounded strongly in 2010, both in mature industrialised countries and in developing countries, global energy consumption also saw a very strong growth of 5.6%, which is the largest annual growth since 1973 when the world was recovering from the recession caused by the first oil price crisis
Like Russia, Ukraine has seen a greater reduction in CO2 emissions since 1990 than laid out in the Kyoto Protocol - the reason being the collapse of national industry in the 1990s. The result was such a dramatic drop in emissions that in recent years, the country saw a welcome boost to state funds received from the trade of carbon emission quotas.
The reduction was not because of lower population.