Reciprocal interactions between a non-native shrub and the dominant native trees of a high mountain woodland:who benefits?

TAPELLA, MARÍA PAZ; MARCORA PAULA INÉS; PAULA ANDREA TECCO

BIOLOGICAL INVASIONS

SPRINGER

Lugar: Berlin; Año: 2021

1387-3547

Facilitation by nurse plants is a commoninteraction, whereby climatic harshness and/or otherlimiting factors are reduced under the canopy of the??nurse?? plant, favoring the regeneration of other plantspecies. In mountain systems, nurse plant interactionsamong coexisting native and non-native woodyspecies might reciprocally affect the regenerationpatterns of the involved species. Elucidating theserelationships might contribute to the understanding ofinteractions that facilitate the success of non-nativewoody species at high elevations. We assessedwhether the non-native shrub Cotoneaster franchetiiand the dominant native trees Polylepis australis andMaytenus boaria, reciprocally affect each other?sregeneration in highland woodlands of central Argentina.We recorded woody recruits (seedlings andsaplings) and micro-environmental conditions underthe three nurse plants and in gaps without woodycover. The frequency of occurrence of Cotoneasterand Maytenus recruits differed among microhabitats.Polylepis regeneration in the area was almost null. Thehighest Cotoneaster recruit frequency was under thecanopy of conspecifics and Polylepis. Maytenusrecruit frequencies did not differ among microhabitats,but saplings had higher frequency under Polylepisthan under conspecific nurses. The apparently higherquality of Polylepis as nurse plant might be related tointermediate conditions of photosynthetically activeradiation and milder winter temperatures under itscanopy. Non-native shrub regeneration seems to befacilitated by one of the native species, whereasneither of the natives seems to be favored by theinvader. These results support the importance of bioticinteractions as drivers of woody invasion success inmountain ecosystems.