Predecir la distribución de un ecosistema cada vez más vulnerable : el pasado, el presente y el futuro de los bosques de Polylepis

Esta investigación tuvo como objetivo predecir la distribución actual de especies y bosques de Polylepis, la distribución durante el Último Máximo Glacial (LGM) y los cambios en la distribución de especies resultantes del doble de CO2 atmosférico. La distribución actual, LGM y futura como resultado del cambio climático se pronosticaron para 21 especies de Polylepis utilizando el algoritmo Maxent sobre América del Sur. Se utilizaron varias capas ambientales, incluidos los datos de detección remota climática, óptica y de microondas, para escenarios climáticos particulares. Se pronostica que la contracción del rango se producirá para la mayoría de las especies, desde el LGM hasta el clima futuro.This research aimed to predict current Polylepis species and woodland distribution, distribution during the Last Glacial Maximum (LGM), and changes in species distribution resulting from doubled atmospheric CO2. Regions of high Polylepis species richness were characterized, as well as the extent Polylepis woodlands within international and national protected areas throughout the region. Current, LGM, and future distribution as a result of doubled atmospheric CO2 were predicted for 21 species of Polylepis using the Maxent algorithm over South America. Several environmental layers, including climate, optical, and microwave remote sensing data, were used for particular climate scenarios. Range contraction was predicted to occur for most species, from LGM to future climate, as a result of upslope range shifts to smaller land area as a result of increasing annual temperatures. However, the expansion several species ranges were predicted to occur within the Altiplano of Peru and Bolivia as greater land area becomes available. This is contrary to most models of climate change that solely predict contraction in mountain regions. The sites of highest Polylepis species richness did not closely match the current location of protected areas, indicating that the expansion and addition of protected areas are necessary to preserve key areas of high altitude tropical ecosystems. Overall, the management of remaining Polylepis woodlands must take into account the natural distribution of Polylepis species and their response to future climate change to protect this vulnerable ecosystem and the flora, fauna, and human populations that depend on them.Tesi

Formación de un humedal en la costa norte del Perú: Estabilidad biofísica y diversidad biológica

The formation of a coastal wetland located south of Salaverry (La Libertad – Peru) is first described, analyzed, and reported, and their biodiversity is compared with regional wetlands located at coastal areas, using publically access satellite imagery and biological information. An adequate time-series was obtained to hypothesize their formation, calculating the NDVI (Normalized difference vegetation index) and NDMI (Normalized Difference Moisture Index) to confirm the stability and influence. The analysis suggests that the wetland south of Salaverry was formed fifteen years ago by two human sources: freshwater infiltration from farmlands and seawater used to pump the dredged material in the vicinity of the Salaverry Port. Because of its ecosystemic features, the wetland would be at the first stages of the ecological succession, and despite its spontaneous origin, it will be functioning as a brackish coastal lagoon attracting opportunistic fauna, mainly birds.Se describe, analiza y reporta por primera vez la formación de un humedal costero en el sur de Salaverry (La Libertad, Perú). Se realiza la comparación del número de especies con otros humedales ubicados en áreas costeras de la región, empleando para ello imágenes satelitales de acceso público e información biológica. Se obtuvo una serie de tiempo suficiente para plantear una hipótesis sobre su formación, calculando el NDVI (Índice de Vegetación de Diferencia Normalizada) y NDMI (Índice de Humedad de Diferencia Normalizada) para confirmar su estabilidad e influencia. El resultado del análisis sugiere que el humedal sur de Salaverry se formó hace quince años por dos aportes antrópicos: filtraciones de agua dulces desde terrenos agrícolas y agua de mar usada para el bombeo del material dragado en las inmediaciones del Puerto de Salaverry. Por sus características ecosistémicas, el humedal se encontraría en las primeras etapas de sucesión ecológica, y a pesar de origen espontáneo, estaría operando como una laguna costera salobre que atrae fauna oportunista, principalmente aves

Coupling remote sensing and eDNA to monitor environmental impact: A pilot to quantify the environmental benefits of sustainable agriculture in the Brazilian Amazon

Monitoring is essential to ensure that environmental goals are being achieved, including those of sustainable agriculture. Growing interest in environmental monitoring provides an opportunity to improve monitoring practices. Approaches that directly monitor land cover change and biodiversity annually by coupling the wall-to-wall coverage from remote sensing and the site-specific community composition from environmental DNA (eDNA) can provide timely, relevant results for parties interested in the success of sustainable agricultural practices. To ensure that the measured impacts are due to the environmental projects and not exogenous factors, sites where projects have been implemented should be benchmarked against counterfactuals (no project) and control (natural habitat) sites. Results can then be used to calculate diverse sets of indicators customized to monitor different projects. Here, we report on our experience developing and applying one such approach to assess the impact of shaded cocoa projects implemented by the Instituto de Manejo e Certificação Florestal e Agrícola (IMAFLORA) near São Félix do Xingu, in Pará, Brazil. We used the Continuous Degradation Detection (CODED) and LandTrendr algorithms to create a remote sensing-based assessment of forest disturbance and regeneration, estimate carbon sequestration, and changes in essential habitats. We coupled these remote sensing methods with eDNA analyses using arthropod-targeted primers by collecting soil samples from intervention and counterfactual pasture field sites and a control secondary forest. We used a custom set of indicators from the pilot application of a coupled monitoring framework called TerraBio. Our results suggest that, due to IMAFLORA’s shaded cocoa projects, over 400 acres were restored in the intervention area and the community composition of arthropods in shaded cocoa is closer to second-growth forests than that of pastures. In reviewing the coupled approach, we found multiple aspects worked well, and we conclude by presenting multiple lessons learned

Modeled Shifts in Polylepis Species Ranges in the Andes from the Last Glacial Maximum to the Present

Polylepis woodlands, the dominant high-elevation woodland species of the Andes of South America, are an increasingly important focus of conservation and restoration efforts as a buffer to the regional effects of climate change. However, the natural extent of these woodlands before the arrival of human populations is still debated. One significant approach to this question is an assessment of the change in woodland extent from a hypothetical peak at the time of the Last Glacial Maximum (LGM) to the present where distributions have been altered by both Holocene climate oscillations and anthropogenic pressures of pre-Colombian and modern communities. LGM and present distributions for 21 Polylepis species were modeled using Maxent with environmental data obtained from the WorldClim database. Overall, potential woodland extent is 36% smaller today than at LGM, however a few species have experienced a projected increase in potential range of 180%. This has occurred at the interface of the southern Amazonian Basin with the Altiplano where Polylepis species richness is highest. Bioclimatically stable areas for each species averaged 20 ± 4% of the modeled range and mostly occurred in disjunct pockets from central Peru to northern Argentina and Chile

Formación de un humedal en la costa norte del Perú: Estabilidad biofísica y diversidad biológica

Se describe, analiza y reporta por primera vez la formación de un humedal costero en el sur de Salaverry (La Libertad, Perú). Se realiza la comparación del número de especies con otros humedales ubicados en áreas costeras de la región, empleando para ello imágenes satelitales de acceso público e información biológica. Se obtuvo una serie de tiempo suficiente para plantear una hipótesis sobre su formación, calculando el NDVI (Índice de Vegetación de Diferencia Normalizada) y NDMI (Índice de Humedad de Diferencia Normalizada) para confirmar su estabilidad e influencia. El resultado del análisis sugiere que el humedal sur de Salaverry se formó hace quince años por dos aportes antrópicos: filtraciones de agua dulces desde terrenos agrícolas y agua de mar usada para el bombeo del material dragado en las inmediaciones del Puerto de Salaverry. Por sus características ecosistémicas, el humedal se encontraría en las primeras etapas de sucesión ecológica, y a pesar de origen espontáneo, estaría operando como una laguna costera salobre que atrae fauna oportunista, principalmente aves

Modeling a cold-air drainage event with a wireless sensor network

A wireless network of sensors was used to characterize a cold-air drainage event in the canyon surrounding the James Reserve. The flow of cold air at night and the first hours of sunrise have major ecological consequences by limiting the vegetation types to those tolerant of freeze and thaw cycles. A network of wireless sensors provides the opportunity to track this event in real time and fully characterize the cold air flow down the canyon, which may last 1.5 hours, and the pooling of cold air in low lying areas. By adjusting the spatial extent of the wireless sensors and the time interval between data capture, we can optimize the spatial and temporal extent of a sensor network and its ability to describe multiple cold-air drainage events