Physiognomic responses of páramo tussock grass to time since fire in northern Ecuador / Respuestas fisionómicas de las macollas de gramínea del páramo posteriores a incendios en el norte del Ecuador

Abstract Ecologically-sound management plans for high-altitude grasslands of the Andes depend on an understanding the responses of plants to fire, especially the dominant tussock grasses. This study considers physiognomic responses of tussock grass in 13 sites in northern Ecuador with a known fire history, with time since fire 0.5-10 y, and a control site which had not been burned for at least 40 y. At each site, we assessed vegetation height, basal cover of the tussocks, and the ratio of dead:live leaves in tussocks. We also measured light at ground level. As recovery time increased, tussock cover and number decreased, while tussock height increased. Light levels fell sharply below the tussock canopies as recovery took place, and dead leaves accumulated quickly, reaching 60 - 70% by just two years after fire. The modification of physical tussock structure is likely to influence a much wider ecosystem response to fire, and determines directly the fuel load for future fires. Despite these clear changes in tussock characteristics, they were too variable to be used as a reliable bioindicator of time since fire. However, a better understanding of the responses of tussock grasses to fire and particularly its impact on other species should become the focus of further attention in future.

Resumen Los planes de manejo ecológicamente sólidos para los pastizales de gran altura en los Andes dependen del entendimiento de las respuestas de las plantas al fuego, en especial las respuestas de los pastos dominantes. Este estudio considera las respuestas fisionómicas de pastos en 13 sitios en el norte del Ecuador con un historial de incendios conocido, con tiempo entre 0.5 y 10 años después del incendio, más un sitio control donde al menos durante 40 años no se había producido incendio. En cada sitio, evaluamos la altura de la vegetación, la cobertura basal de las macollas y la proporción de hojas muertas:vivas en las macollas. También, medimos la luz a nivel del suelo. A medida que aumentó el tiempo de recuperación, la cobertura y el número de macollas disminuyeron, mientras que la altura de las macollas aumentó. Los niveles de luz cayeron fuertemente debajo de las copas de las macollas durante la recuperación, y las hojas muertas se acumularon rápidamente, alcanzando 60 - 70% solo dos años después del incendio. Es probable que las modificaciones en la estructura física de las macollas influyen en una respuesta mucho más amplia del ecosistema al fuego, y determinen directamente la carga de combustible para futuros incendios. A pesar de que se observaron cambios claros en las características de las macollas, estas eran demasiado variables para ser consideradas como un bioindicador confiable del tiempo transcurrido después del incendio. Sin embargo, una mejor comprensión de las respuestas de las macollas al fuego y, en particular, el impacto de esas respuestas en otras especies debería ser el enfoque de mayor atención en el futuro.

Current and future suitable habitat areas for Nasuella olivacea (Gray, 1865) in Colombia and Ecuador and analysis of its distribution across different land uses.

Nasuella olivacea is an endemic mammal from the Andes of Ecuador and Colombia. Due to its rarity, aspects about its natural history, ecology and distribution patterns are not well known, therefore, research is needed to generate knowledge about this carnivore and a first step is studying suitable habitat areas. We performed Ecological Niche Models and applied future climate change scenarios (2.6 and 8.5 RCP) to determine the potential distribution of this mammal in Colombia and Ecuador, with current and future climate change conditions; furthermore, we analysed its distribution along several land covers. We found that N. olivacea is likely to be found in areas where no records have been reported previously; likewise, climate change conditions would increase suitable distribution areas. Concerning land cover, 73.4% of N. olivacea potential distribution was located outside Protected Areas (PA), 46.1% in Forests and 40.3% in Agricultural Lands. These findings highlight the need to further research understudied species, furthering our understanding about distribution trends and responses to changing climatic conditions, as well as informig future PA designing. These are essential tools for supporting wildlife conservation plans, being applicable for rare species whose biology and ecology remain unknown.