Spatial association of lemming burrows with landforms in the Swedish subarctic mountains : implications for periglacial feature stability

摘要

Burrowing mammals often have considerable geomorphological impacts, and theirtunneling activities may decrease the stability of landforms. We document the spatialdistribution of Norwegian lemming burrows in a subarctic alpine meadow todetermine the preferred locations for burrow entrances and to examine the potentialfor burrowing to decrease the stability of periglacial landforms at the site. Burrowentrances were disproportionately common into the base and sides of landforms(.68% of burrows), probably reflecting the lower energetic cost of moving soilhorizontally, rather than vertically, out of burrows. Most burrow entrances (.60%)were also located under large rocks, which probably improve burrow stability byproviding a firm ceiling to the entrance. Field observations show that these burrowsare relatively stable, as only 3% were associated with any signs of increased erosionor landform instability. Therefore, in contrast to some previous studies, and despiteburrowing being concentrated on landforms, we suggest that these rodents have littledirect impact on landform integrity at this site.