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The Valdivian temperate rainforest (VTR) is a biome on the South American continent with high endemism that has experienced an intensive land-cover change in recent decades due to the expansion of agriculture, plantations of introduced forests, and urban growth. Today, the biome hosts key parts of the country's agricultural and forestry industries. Previous studies focused on quantifying native forest and plantation cover area and exotic forest plantation area, among others. However, the importance of mountain areas as refuge of native forest in Chile remains unexplored. The aim of this research is to highlight the role of latitude and slope on land cover in the VTR. A new methodological approach was used combining global classified datasets. Our results indicate that high mountain areas are the core location of the remaining primary forests and endemism whereas low mountain areas are dominated by exotic forest plantations. Between 40–48° S (The Los Ríos, Los Lagos, and Aysén Regions and high-mountain areas), in general, serve as a natural reservoir where human-induced land-cover change has not occurred on a large scale. Most public and private conservation areas are in high mountain areas, whereas low mountain areas and plain areas lack conservation schemes and are more prone to land cover change towards forestry. Considering geomorphological features in land cover change analysis can reveal interesting new perspectives in this research area. [ABSTRACT FROM AUTHOR]

The Valdivian temperate rainforest (VTR) is a biome on the South American continent with high endemism that has experienced an intensive land-cover change in recent decades due to the expansion of agriculture, plantations of introduced forests, and urban growth. Today, the biome hosts key parts of the country’s agricultural and forestry industries. Previous studies focused on quantifying native forest and plantation cover area and exotic forest plantation area, among others. However, the importance of mountain areas as refuge of native forest in Chile remains unexplored. The aim of this research is to highlight the role of latitude and slope on land cover in the VTR. A new methodological approach was used combining global classified datasets. Our results indicate that high mountain areas are the core location of the remaining primary forests and endemism whereas low mountain areas are dominated by exotic forest plantations. Between 40–48° S (The Los Ríos, Los Lagos, and Aysén Regions and high-mountain areas), in general, serve as a natural reservoir where human-induced land-cover change has not occurred on a large scale. Most public and private conservation areas are in high mountain areas, whereas low mountain areas and plain areas lack conservation schemes and are more prone to land cover change towards forestry. Considering geomorphological features in land cover change analysis can reveal interesting new perspectives in this research area.

Climate changes during the late Pleistocene influenced the demography and distribution of species in Patagonia. During the last glacial maximum (LGM), ice sheets covered a great extent of the temperate rainforest in the western Patagonian Andes. The persistence of forest species in refugia during the LGM has been debated for many vertebrates, but rarely for birds. The Green-backed Firecrown (Sephanoides sephaniodes) is an important avian pollinator distributed from the south of the Atacama Desert (28°S) to Tierra del Fuego (54°S) in South America. We evaluated the species' evolutionary history, combining molecular data and models for past and current species distribution. Our results show two distinct haplogroups: the genetically diverse North–South clade (NS) restricted to the Mediterranean and coastal temperate regions that exhibits a signature of population expansion after LGM, and the Austral-East clade (AE) confined to the temperate intermountain range, eastern temperate, and sub-Antarctic regions, with lower genetic diversity and evidence of a more recent population expansion. This AE clade and the past distribution models support the species survival in valleys and lowlands south of the ice sheets limit during LGM until the present. A secondary contact zone was observed with haplotypes from the AE clade distributed in low frequency along with the northern areas. Our results support the paleorefugia hypothesis during the LGM with postglacial secondary contact. [ABSTRACT FROM AUTHOR]

Species abundance is an important ecological parameter that can provide insights on ecological and evolutionary processes. Here, we report patterns of abundance for two coexisting Ceroglossus ground beetle species (C. buqueti and C. darwini) from a Valdivian temperate rainforest area in South Chile, sampled at four time periods within a year. Results show similar overall species abundances, although they varied differently along the year for each species. The abundance of the species C. darwini peaked earlier than the species C. buqueti and it was absent during fall and winter, while C. buqueti was detected at all seasons. Abundances also varied spatially, but they were positively correlated between species suggesting no spatial segregation. Carabidae, Chile, species abundance, Valdivian temperate rainforest.

Four recent studies on Chilean vertebrates underscore the very different effects that habitat fragmentation may have under different conditions. In southern Chile, birds exhibited significant species-area relationships, whereas the more depauperate small mammal community did not. The avifauna of highly isolated rainforest remnants in Fray Jorge National Park (IV Región) presented steeper species-area relations than those in southern Chile, reminiscent of land-bridge islands after faunal relaxation. The small mammal results were unexpected but may reflect the reduced vagility and immigration potential of this group. Additionally, the inter-remnant matrix habitat may support large populations of only some species, allowing them to capitalize on resources that are available in forest remnants. Such an effect is less likely for birds due to their greater vagility. Although the influence of remnant area is more clearly demonstrated for birds in Chile, it appears that small mammal assemblages may be more immediately impacted by habitat fragmentation than are birds, and that further fragmentation of temperate rainforests will seriously impoverish the small mammal assemblage, many of whose members are endemic to this region. Further research should emphasize the role of the inter-remnant matrix, of habitat corridors, and of the relative sensitivity of different species to matrix/corridor quality and remnant isolationCuatro estudios recientes en vertebrados chilenos subrayan los efectos muy diversos que la fragmentación del hábitat puede tener bajo diversas condiciones. En el sur de Chile, las aves exhibieron relaciones significativas entre la riqueza de especies y el área de hábitat ("especies-area"), mientras que tal relación no se observó en la comunidad de pequeños mamíferos, la cual tiene menos especies. La avifauna de los fragmentos remanentes altamente aislados del Parque Nacional Fray Jorge (IV Región) presentaron relaciones especies-área más pronunciadas que aquellas de Chile meridional. Lo observado para los pequeños mamíferos fue inesperado aunque puede reflejar un menor potencial de movilidad e inmigración en este grupo. Además, el hábitat de la matriz inter-fragmento puede albergar solo a poblaciones grandes de algunas especies, lo que les permitiría capitalizar los recursos que están disponibles en los fragmentos de bosque. Tal efecto es menos probable para el caso de las aves producto de su mayor movilidad. Aunque la influencia del área de los fragmentos remanentes es más claro en el caso de las aves en Chile, es probable que los ensambles de mamíferos pequeños sean más afectados en el corto plazo por la fragmentación del hábitat que las aves, y que una fragmentación adicional de los bosques templados lluviosos determinará un mayor empobrecimiento de los ensambles de pequeños mamíferos, muchos de los cuales son endémicos en esta región. Estudios adicionales deberían enfatizar el papel de la matriz ínter-fragmento, el de los corredores de hábitat, y evaluar la sensibilidad relativa de diversas especies al aislamiento de los fragmentos remanentes y a la calidad de la matriz/corredor

Cultivable actinomycetes associated to lichenized microecosystems from the temperate Valdivian rainforests, Argentina. Twenty-three (23) cultivable strains of actinomycetes were isolated from the corticolous lichen species Pseudocyphellaria berberina present in the Valdivian temperate rainforest, Argentina, being twenty-one (21) endolichenic and two (2) ectolichenic. Seventeen (17) strains were identified as belonging to genera Actinoplanes (2), Dactylosporangium (1), aff. Pseudonocardia (1), Micromonospora (6), aff. Micromonospora (1) and Streptomyces (5), Streptosporangoium (1). This is the first record of actinomycetes isolated from lichenized fungi for Argentina. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizas (AM) are one of the most widespread types of symbiotic associations. Pteridophytes occupy an important position in the evolution of vascular plants. However, their mycorrhizal state remains poorly understood. The aim of this work was to describe the general mycorrhizal status and the occurrence of dark septate endophytes (DSE) in the pteridophytic flora of a Valdivian temperate forest in Patagonia, Argentina. First, the roots of nine terrestrial species representing six families were examined, and this information was then compared with other surveys concerning the occurrence of AM in other pteridophytic species within the same Valdivian temperate forest. AM were recorded in 98.6% of the samples analyzed in this work and all of them corresponded to the Paris-type morphology. DSEs were also present within the roots of all terrestrial species. A comparison to published results in other ferns and lycophytes that have been studied in this Valdivian temperate forest (161 sporophytes, 21 species and 10 families) was made. Clear differences in colonization patterns between eusporangiate/leptosporangiate and epiphytic/terrestrial species became evident and are discussed. [ABSTRACT FROM AUTHOR]