Informal road networks and sustainability of Siberian boreal forest landscapes: case study of the Vershina Khandy taiga

Boreal forest landscapes are experiencing various anthropogenic pressures from industrial activity, transportation, urbanization, and recreation compounding already significant changes in regional climate. However, the impact of the transportation infrastructure on boreal forests is rarely considered, and information about road extent is often incomplete, especially in the case of informal roads. Using a combination of landscape observations and interviews with local residents this case study examines the role of informal roads, i.e. vehicular roadways existing outside of the current publicly governed road networks, in transforming Siberian boreal forest landscapes in the Vershina Khandy taiga, Russia. Informal roads constitute 88% of the total road length in the study area and exert significant and multifaceted effects on social-ecological systems and landscape sustainability. Native dark coniferous forests have been disturbed by cutting, logging and human-caused fires proliferated from the roads. In their immediate vicinity, the informal road networks also exacerbate the replacement of primary forests with different successional states. Landscape vulnerability was assessed using three main factors of road-related disturbance: erosion, permafrost degradation and wildfires. Valley landscapes, where roads are prevalent, found to be the most vulnerable to environmental degradation. They are more often located within the wetlands with permafrost occurrences. The impact of informal roads is not limited to environmental changes. Among consequences there are also increased mobilities of local and Indigenous communities, as well an improved access to the area by outsiders: recreational anglers and poachers. The effects on subsistence activities and mobility vary across different landscapes. Further research on natural and social components of landscape sustainability in boreal forests affected by informal road networks is needed to better understand the local, regional and global role of this phenomena.