Dead planet, living planet

CASE STUDY #9

In Arctic tundra, vehicles from seismic exploration, military training, mining or recreational 4wd ATVs may leave heavy marks in tundra and permafrost, lasting for decades or even Marks from vehicles in Arctic tundra

centuries. Many restoration programmes focus on transplant- ing local plants to accelerate natural processes.

Graminoid-dominated strip characteristic of off-road vehicle tracks that have regenerated naturally. Disused for ≈ 20 yr at the time of the photo, these are visible as linear features in very high resolution satellite imagery (see Forbes et al. 2009). Shrubs are completely displaced by such activity as the initial mechanical disturbance removes woody biomass and this is replaced by fast- growing, clonal graminoids (grasses, sedges) that can then occupy the patch indefinitely. On drier ground, regeneration of a complete plant cover may take decades, or not occur where nutrients and moisture are inadequate.

Fresh off-road vehicle tracks through sedge-moss tundra in the Nenets Autonomous Okrug, Arctic Russia. Such ruts form easily, yet tend to regenerate naturally relatively quickly in the absence of any slope or fluvial erosion. Vehicle tracks remain common in the Russian Arctic despite an official ban on their use in summer, when the ground surface is thawed, since the 1980s. Roads have the effect of reducing such traffic, yet lead to other, indirect im- pacts that may persist for decades, such as blowing sand, dust and changes in hydrology and chemistry in the vicinity of the road (see Forbes et al. 2001).

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