Person: Acosta Gallo, Belén
Loading...
First Name
Belén
Last Name
Acosta Gallo
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Biodiversidad, Ecología y Evolución
Area
Ecología
Identifiers
5 results
Search Results
Now showing 1 - 5 of 5
Item From Spain to Chile: environmental filters and success of herbaceous species in Mediterranean-climate regions(Biological Invasions, 2015) Martín Forés, Irene; Sánchez Jardón, Laura; Acosta Gallo, Belén; Pozo Lira, Alejandro del; Castro Parga, Isabel; Miguel Garcinuño, José Manuel de; Ovalle, Carlos; Casado González, Miguel ÁngelIn central Chile, many exotic species associated with cereal culture and livestock activities were introduced during Spanish colonization. Nowadays, Chilean semi-natural grasslands are a mixture of native species and exotics that mainly originated in the Mediterranean Basin. The establishment and persistence of exotics (i.e. naturalization) can be due to abiotic (climate and soil properties) and biotic (interaction between plants) factors. We assess the importance of these environmental factors as filters that have promoted/ limited the successful naturalization of Spanish species in Chile. Fifteen sites distributed throughout a wide range of Mediterranean climatic conditions, with similar geomorphology and land-use, were selected in both Chile and Spain. At each site we recorded a broad set of soil and climate variables as well as plant species richness during two consecutive years. In Chile, species were classified as natives or exotics whereas in Spain species were classified as colonizers (species that have been naturalized in Chile) or exclusives (only present in Spain).Species richness was higher in Spain (229 species) than in Chile (152), the latter with a high proportion (almost 50 %) of exotics. Different environmental factors affected species richness in each Mediterranean region. In Spain, species classified as colonizers were weakly related to a combination of soil and climate properties, while in Chile the number of exotic species was highly related with climate conditions (especially water availability). Lack of association between native and exotics pecies richness indicated that biotic filters (i.e. species competition) are less important than abiotic ones in transcontinental naturalization in Chile.Item Alien plant species coexist over time with native ones in Chilean Mediterranean grasslands(Journal of Plant Ecology, 2016) Martín Forés, Irene; Castro Parga, Isabel; Acosta Gallo, Belén; Pozo Lira, Alejandro; Sánchez Jardón, Laura; Miguel Garcinuño, José Manuel de; Ovalle, Carlos; Casado González, Miguel ÁngelAims Alien species are commonly considered as harmful weeds capable of decreasing native biodiversity and threatening ecosystems. Despite this assumption, little is known about the long-term patterns of the native–alien relationships associated with human disturbed managed landscapes. This study aims to elucidate the community dynamics associated with a successional gradient in Chilean Mediterranean grasslands, considering both native and alien species. Methods Species richness (natives and aliens separately) and life-form (annuals and perennials) were recorded in four Chilean post-agricultural grazed grasslands each covering a broad successional gradient (from 1 to 40 years since crop abandonment). A detrended correspondence analysis (DCA), mixed model effects analyses and correlation tests were conducted to assess how this temporal gradient influenced natives and aliens through community dynamics. Important Findings Our results show different life-form patterns between natives and aliens over time. Aliens were mainly represented by annuals (especially ruderals and weeds), which were established at the beginning of succession. Annual aliens also predominated at midsuccessional stages, but in old grasslands native species were slightly more representative than alien ones within the community. In the late successional states, positive or no correlations at all between alien and native species richness suggested the absence of competition between both species groups, as a result of different strategies in occupation of the space. Community dynamics over time constitute a net gain in biodiversity, increasing natives and maintaining a general alien pool, allowing the coexistence of both. Biotic interactions including facilitation and/or tolerance processes might be occurring in Chilean post-agricultural grasslands, a fact that contradicts the accepted idea of the alien species as contenders.Item Variability of herbaceous productivity along Nothofagus pumilio forest-open grassland boundaries in northern Chilean Patagonia(Agroforestry Systems, 2014) Sánchez Jardón, Laura; Acosta Gallo, Belén; Pozo Lira, Alejandro del; Casado González, Miguel A.; Ovalle Molina, Carlos; Miguel Garcinuño, José Manuel deIn order to develop a general model of aboveground net primary production (ANPP) of herbaceous communities in grazing systems that combine forested and open grasslands in temperate areas, biomass production and a set of biotic and abiotic variables were measured at four adjacent forest and grassland sites in Chile’s northern Patagonia for two consecutive growing seasons. At each site, one transect of 80 m long (40 m in open grassland and 40 m in forest) × 10 m wide was established. ANPP was significantly higher in open grasslands but no gradual change in biomass production was observed from inside the forest towards the open grassland. In open grasslands ANPP was spatially uniform but highly variable between years of contrasting weather conditions, whereas in forests it was more spatially heterogeneous and less variable over time. ANPP was highly correlated with cattle consumption. Structural equation models developed for the whole system confirm that ANPP was driven mainly by photosynthetically active radiation (PAR) and available nitrogen. However, we found important differences between forests and the adjacent open grasslands. In forests ANPP was enhanced by positive feedbacks between the amount of transmitted PAR through the canopy and soil nutrient input via cattle dung deposition. In open grasslands nitrogen availability appeared to be the main limiting factor but also influenced by weather conditions (dryer or wetter years). The coexistence of forests and grasslands patches, with different susceptibility of ANPP to meteorological and soil nutrient availability, highlights the importance of implementing an integrated silvopastoral system with lenga (Nothofagus pumilio [Poepp. & Endl.] Krasser) in northern Patagonia.Item Interactive effects of source and recipient habitats on plant invasions: distribution of exotic species in Chile(Diversity and Distributions, 2015) Casado Hernández, Miguel Ángel; Acosta Gallo, Belén; Sánchez Jardón, Laura; Martín Forés, Irene; Castro Parga, Isabel; Ovalle, Carlos; Pozo Lira, Alejandro; Miguel Garcinuño, José Manuel deAim: Most studies on invasibility consider the characteristics of the habitats colonized. However, the success of the establishment of exotic species can be conditioned by the characteristics of the donor communities. In this study, we analyse the extent to which the distribution of exotic herbaceous species in Chile is conditioned either by the climatic characteristics of the recipient area or by the environmental features of the source areas on the Iberian Peninsula. Location: Chile and the Iberian Peninsula (Portugal and Spain). Methods: for Chile, we characterized the exotic species according to their current Chilean distribution and their region of origin. For the Iberian Peninsula, we compiled the floristic composition of 11,702 releves. We classified each releve according to key habitat characteristics (bioclimate, soil nutrient status and type of community associated with human activities) and calculated the percentage of species in common with Chile in different climatic regions therein. Results: Over half of Chile’s exotic species exhibited a geographic distribution related to the climate of the recipient area. The main donor communities were those associated with ruderal and arable land habitats, although their importance depended upon the climate in the recipient area. Correspondence was observed between the climatic characteristics of the communities in the source area and those of the recipient areas. Main conclusions: the results highlight the influence of the characteristics of habitats in the source area on the successful establishment of exotic species in Chile. The relationships between source and recipient area are scale dependent, climate constituting the main driver at broad scale. Within each climatic region, the communities associated with habitats presenting greater anthropic influence act as the main donors. Both features indicate the existence of filters that select species pre-adapted to the climatic and habitat conditions in the recipient area.Item Ecotypic differentiation and phenotypic plasticity combine to enhance the invasiveness of the most widespread daisy in Chile, Leontodon saxatilis(Scientific Reports, 2017) Martín Forés, Irene; Avilés, Marta; Acosta Gallo, Belén; Breed, Martin F.; Pozo Lira, Alejandro del; Miguel Garcinuño, José Manuel de; Sánchez Jardón, Laura; Castro Parga, Isabel; Ovalle, Carlos; Casado González, Miguel ÁngelDispersal and reproductive traits of successful plant invaders are expected to undergo strong selection during biological invasions. Numerous Asteraceae are invasive and display dimorphic fruits within a single flower head, resulting in differential dispersal pathways - wind-dispersed fruits vs. nondispersing fruits. We explored ecotypic differentiation and phenotypic plasticity of seed output and fruit dimorphisms in exotic Chilean and native Spanish populations of Leontodon saxatilis subsp. rothii. We collected flower heads from populations in Spain and Chile along a rainfall gradient. Seeds from all populations were planted in reciprocal transplant trials in Spain and Chile to explore their performance in the native and invasive range. We scored plant biomass, reproductive investment and fruit dimorphism. We observed strong plasticity, where plants grown in the invasive range had much greater biomass, flower head size and seed output, with a higher proportion of wind-dispersed fruits, than those grown in the native range. We also observed a significant ecotype effect, where the exotic populations displayed higher proportions of wind-dispersed fruits than native populations. Together, these patterns reflect a combination of phenotypic plasticity and ecotypic differentiation, indicating that Leontodon saxatilis has probably increased propagule pressure and dispersal distances in its invasive range to enhance its invasiveness.