RODRIGUEZ CABAL mariano Alberto
congresos y reuniones científicas
The role of seed predation on Pinaceae invasion in Patagonia
CHIUFFO, MARIANA C.; MOYANO, JAIME; MARIANO A. RODRIGUEZ CABAL; MARTIN A. NUNEZ
Congreso; British Ecological Society; 2017
British Ecological Society
Generalist seed predators can be an important filter to nonnative species invasion. However, it is unclear if the importance of this filter change with factors that could influence plant-granivore interactions. Here we evaluated whether seed predation in nonnative pinaceae is affected by abiotic gradients, seed traits and distances from seed sources in northwest Patagonia (Argentina). To assess whether seed predation varies along an abiotic gradient, we evaluated seed removal of nonnative pinaceae species at ten sites where annual precipitation ranged from 600mm to 1600mm. Additionally, in native grasslands we evaluated native predators preference for seeds of 18 different species, ranging in individual seed mass from 3.6 mg to 760mg. Finally, in native grasslands adjacent to a Pine plantations, we assessed seed predation in transects with decreasing seed availability as the distance to the plantation increased up to 200m, following the natural seed dispersion pattern. Seed predation increased with precipitation, i.e. predation was higher in less stressful environments (higher precipitation) compared to harsh ones. Pine species with smaller seeds suffer higher levels of seed predation. At last, our results showed that Pine invasion is limited to very short distances because propagule pressure is overcome by seed predation (biotic resistance) at higher distances. Jointly these results show that the interplay of different factors can determine seed predation patterns and may be key to explain pine invasions in Patagonia.