The Tropical Montane Cloud Forests (TMCF) of South America are ecosystems facing rapid changes due to global warming. Herein, we used species climatic niche models to reconstruct the climatic boundaries of TMCF and to predict range shifts in climate change scenarios. Thirty-two species from three taxonomic groups (plants, birds, and amphibians) were modelled using community-level niche models under current and future climatic scenarios, as determined by two Global Climate Models (GCMs) for the year 2050. The community-level reconstructions were used to detect the overlap of TMCF with surrounding ecosystems and with current protected areas (PA). Approximate 42–54% area reduction and 207–429 m upward elevational shift was predicted under climate scenarios. Accordingly, severe environmental contractions (loss of suitability area) due to climate change were detected by our models. TMCF area within PA may increase 17–38% by 2050. We identified transition zones rather than clear limits of vegetational boundaries of TMCF with adjacent ecosystems, which suggested that both TMCF and transitional zones will be impacted, to what conservation strategies targeting TMCF and adjacent ecosystems should be prioritized.
Habitat loss and fragmentation caused by deforestation are important anthropogenic drivers of changes in biodiversity in the Amazon rainforest, and has reached its highest rate in recent decades. However, the magnitude and direction of the effects on species composition and distribution have yet to be fully understood. We evaluated the responses of four taxonomic groups − birds, amphibians, orchid bees, and dung beetles-to habitat loss and fragmentation at both species and assemblage level in the northern Ecuadorian Amazon. We sampled fifteen 250-m long plots in terra-firme forest remnants. We calculated one landscape fragmentation index (fragindex), which considers the proportion of continuous forest cover, edge density and isolation in the landscape, and nine landscape configuration metrics. Logistic regression models and multivariate regression trees were used to analyze species and assemblage responses. Our results revealed that over 80% of birds, amphibians or orchid-bee species, and 60% of dung beetles were negatively affected by habitat loss and fragmentation. Species composition of all taxonomic groups was significantly affected by differences in forest cover and connectivity. Less than 5% of all species were restricted to landscapes with fragindex values higher than 40%. Landscape metrics related to the shape and area of forest patches determined the magnitude and direction of the effect on species responses. Therefore, changes in the landscape configuration of Ecuadorian Amazonia should be minimized to diminish the effects of habitat loss and fragmentation on species occurrence and assemblage composition.
A pesar de que su presencia ha sido confirmada en varias localidades de la Cordillera Central en los Andes, la distribución de la danta de montaña (Tapirus pinchaque; <200 kg; EN) ha sido poco estudiada en Colombia. Por ello, se han estimado las áreas potenciales de distribución actual y bajo escenarios de cambio climático futuros, considerando el efecto de la pérdida del hábitat, la disponibilidad de los ecosistemas y el rol del actual Sistema Nacional de Áreas Naturales Protegidas (SNANP) para la especie en Colombia. El modelo de idoneidad climática estimó una extensión de ocurrencia de ~28.000 km2, con una reducción inferida del 38,11% por efecto de la pérdida del hábitat y del ~35–47% por efectos del cambio climático. Sin embargo, el efecto sinérgico de ambos fenómenos podría representar un riesgo mayor a corto plazo con una reducción estimada del ~55–65% de la distribución potencial. Si bien el actual SINAP incluye un 20,89% de la extensión de ocurrencia de la especie, estas áreas muestran modificaciones en la cobertura boscosa, así como tendencias de cambio en escenarios de cambio climático futuros. Esfuerzos y estrategias de conservación en las áreas no protegidas deben ser promovidos para establecer y mantener la conectividad entre las poblaciones de la especie.
Future predictions developed with Climate Change Models describe changes in precipitation patterns, temperature and changes in the intensity and frequency of extreme weather events, generating a geographic shift of the Ecological Niche and causing threats to species diversity. The intent of this work is to identify priority conservation areas, using the interaction of climatic change scenarios, deforested areas and protected areas with Ecological Niche Models of species of the Dendrobatidae family. Poisonous frogs in Ecuador are represented by 46 species, of which 17.4% are Critically Endangered (CR), 15.22% Endangered (EN), and 8,7% Vulnerable (VU). The environmental suitability of the species covers 256,091km2 (90.31%) of the total of the country, and are present in all the ecosystems of Ecuador. The ecoregions of the Eastern Montane Forest, Amazonian Tropical Humid Forest, Choco Tropical Humid Forest and Western Montane Forest present the greatest abundance and diversity. 46 spp. were analyzed and Ecological Niche Models (ENM) of 35 spp. were generated to get to know the current distribution of the area of environmental suitability and to be able to elucidate its adaptability to different scenarios of future climate change by the year 2050. On average, a contraction of (33.81%) and an expansion of (24.67%) was obtained, confirming the loss of the environmental suitability area. At the same time, the interaction of current species with deforested areas (104,560 km2 - 36.87% -) and protected areas (46,138 km2 - 16.27% -) was analyzed, where 96.60% of deforested areas and 96.95% of protected areas coincide with the environmental suitability areas of this family. Considering the results obtained in the models of diversity, future climate change, endemism, density, threatened species, interaction with deforested areas and with the National System of Protected Areas (SNAP, in Spanish), there are areas of high diversity and endangered endemicity. This generates the need for continuous revisions and updates of the SNAP, where new protected areas are created (Amazon eastern center and eastern foothills of the Andes), others, expanded (Yasuni National Park, Limoncocha Biological Reserve, and Cuyabeno Fauna Production Reserve) and biological corridors that guarantee the non-isolation of species are generated.