The collapse of the Soviet Union in the early 1990s heralded an era of environmental recovery from intensive military and industrial expansion. Since then, greenhouse gas emissions and pollution have rapidly declined. Now, almost 20 years after the dissolution of the USSR, another benefit is beginning to emerge.
In its heyday, the former USSR was home to a large number of highly mechanized, collective farms: the very antithesis of the individual, family-run farms typical of the west. When the Soviet Union collapsed, many of those farms were abandoned, leaving large areas of land (estimated at around 20 million hectares) to be colonized by grassy vegetation. Nicolas Vuichard of the University of Tuscia, Italy, and colleagues, suggest that this agricultural abandonment has significantly increased the size of the region's carbon sink (Glob. Biogeochem. Cycles, doi:10.1029/2008GB003212; 2008).
In an effort to determine how much additional carbon these deserted croplands have taken up, the team used a vegetation model to assess cumulative carbon uptake between 1991 and 2000 in abandoned versus undisturbed agricultural land. The researchers found that following abandonment, the croplands switched from being a small source of atmospheric CO2, releasing approximately 10 g carbon m−2 yr−1, to a significant sink of atmospheric CO2, taking up an average of 47 g carbon m−2 yr−1. The cumulative increase in carbon uptake over this period was 373 g carbon m−2.
The carbon gain during the 1990s resulted from an increase in vegetative returns to the soils, which lost a large amount of carbon in the Soviet era through the intensive harvesting of grain and straw. For this reason, current and future carbon benefits will depend on the management practices employed in the Soviet era — the less carbon farmers returned to the land back then, the greater the benefit we derive today.
Vuichard and colleagues estimate that it will take more than 50 years for the land to reach its pre-USSR carbon levels. In the meantime, the colossal collapse of Soviet agriculture in the early 1990s will be responsible for a net sequestration of 70 Tg carbon over the coming decades. Thus it seems that the Soviet era has inadvertently helped the capitalist world of the twenty-first century to a sizeable carbon sink.
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Changes of Soil C Stock under Establishment and Abandonment of Arable Lands in Permafrost Area—Central Yakutia
Global Change Biology (2014)