Minimum residence time, biogeographical origin, and life cycle as determinants of the geographical extent of naturalized plants in continental Chile

Abstract

The geographical extent of exotic plant species is a major component of invasiveness, which has been explained by intrinsic attributes of the plants, such as growth rate, reproductive type, life form, and biogeographical origin. We assessed quantitatively life cycle and biogeographical origin as determinants of the geographical distribution of naturalized plants in continental Chile, using minimum residence time (MRT) as an estimator of introduction date. We assembled a database with information on 428 plants (principally herbs) in continental Chile, corresponding to 61% of the exotic naturalized flora. For each species we recorded: (1) minimum residence time (introduction date or first recorded date in the country); (2) biogeographical origin (American, Eurasian, others); (3) life cycle (annual, perennial, others); (4) number of Chilean regions occupied by the plant. We found that 82 species (19%) have been recorded in only one region of Chile, while only three species have been found in all 13 regions of the country. About 89% of the species (381) have been found only in central Chile (Regions IV to VIII), while the remaining 11% (47) are found only in the northern (Regions I to III) or southern parts of the country (Regions IX to XII). We detected significant differences in regional spread of naturalized plants according to minimum residence time: those species with shorter MRT had more limited spread ranges than those with longer MRT. Biogeographical origin and life cycle did not explain geographical extent in Chile. This study shows that historical factors are more important than biological ones in determining the geographical extent of naturalized plants in continental Chile. Thus, caution should be exercised when assigning value to biological attributes that may confer invasiveness to naturalized plants.

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

“…Pauchard & Alaback 2004, Becerra 2006, Fuentes-Ramírez et al 2010 on plant invasion. Also, some biogeographical studies have correlated exotic species richness with human settlement documenting greater plant invasion where mostly forest fragmentation and degradation has occurred -mainly in the centre-south region (Arroyo et al 2000, Castro et al 2005. However, in Chile no study has assessed the relationship between fragmentation, degradation and altitude and their effects on plant invasion.…”

Flora Vascular Del Parque Futangue, Región De Los Ríos (Chile)

“…Las especies introducidas registradas en Futangue son principalmente herbáceas y equivalen al 10% del total de las plantas introducidas en Chile continental (Matthei 1995;Castro et al 2005). Tanto las especies endémicas como las nativas la mayoría son herbáceas (19 spp y 107 spp respectivamente) (Tabla II).…”

Invasión de árboles alóctonos en una cuenca pre-andina de Chile central

“…De hecho, Ulmus minor ya fue descrita como invasora en asociaciones vegetales de la cuenca de Santiago hace más de 40 años por Oberdorfer (1960). Una significativa relación entre el momento de llegada a un área y la abundancia y rangos de distribución de especies invasoras ya ha sido documentada antes en Chile (Arroyo et al 2000, Castro et al 2005. Por el contrario, P. nigra, que también posee individuos de alto rango de tamaño, posee una baja a mediana abundancia.…”