Effects of landscape variables on active restoration strategies of restoring Nothofagus forests degraded by invasive beavers in Tierra del Fuego

JUAN MANUEL CELLINI; MARTÍNEZ PASTUR, GUILLERMO; SOLER, ROSINA MATILDE; HENN, JONATHAN JEFFREY; ANDERSON, CHRISTOPHER

Tartu

Congreso; IUFROLE WG Conference; 2015

An agreement between Argentina and Chile to eradicate invasive species was signed due to low resilience of Patagonian forests to the impacts generated by beavers (Castor canadensis). Passive restoration was ineffective, necessitating active strategies. Plantations in abandoned ponds consist of Nothofagus pumilio (lenga) and N. antarctica (ñire). We analyzed the influence of biotic and abiotic factors in 3 micro-habitats: front and tail of ponds and cut non-flooded areas. Five-year-old lenga seedlings had 39% survival in front, 21% in tails and 46% in cut areas in year-3, being negatively influenced by plant cover and soil moisture. Lower height growths were recorded during year-1 (0.7-0.9 cm/year), but increased with time (1.9 cm/year front, 1.6 cm/year tail, 4.3 cm/year cutareas). At 4 locations across bioclimatic zones, 10-40 cm ñire plants attained 17% survival in meadows (front and tail) and 30% in cut areas, being higher in larger plants (25% vs. 18%) influenced by rainfall (4% in sites 400 mm/year). The main damage was from above-ground biomass dryness, but root survival allowed the emergence of new shoots. It is necessary to monitor different Nothofagus species in the environments across landscape to determine feasibility of restoration plans.