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Plant communities in tropical mountains host a high diversity of species’ morphological traits. Many tropical plant species exhibit a wide range of colored fleshy fruits mainly dispersed by animals. Fruits display a variety of shapes including, for instance, capsules with arillate seeds, drupes with fibrous pulp, and juicy berries. These fruits can enclose just one or many tiny seeds which are dispersed by animals. In the tropical mountains of the southeast of Ecuador, seed size can vary from less than 1 mm (e.g., Miconia sp.) to large seeds with a size of almost 10 cm. Despite the high diversity of fleshy-fruited species and the relevance in plant regeneration, there is very little information that facilitates the identification of even the most common fruits and seeds in tropical mountains. The pronounced endemism in the Andes and the constant description of new plant species increase the necessity to foster local publications including these unique species. This project aims to produce an identification guide as a scientific tool to ease the taxonomic determination of seeds dispersed by animals and to speed up the identification process in the mountain forests of the southeast of Ecuador. This field guide will be a source of consultation for future research units at the San Francisco Scientific Station, and will also contribute to public outreach.

Seasonally dry forests in the neotropics are heavily threatened by a combination of human disturbances and climate change; however, the severity of these threats is seldom contrasted. This study aims to quantify and compare the effects of deforestation and climate change on the natural spatial ranges of 17 characteristic tree species of southern Ecuador dry deciduous forests, which are heavily fragmented and support high levels of endemism as part of the Tumbesian ecoregion. We used 660 plant records to generate species distribution models and land-cover data to project species ranges for two time frames: a simulated deforestation scenario from 2008 to 2014 with native forest to anthropogenic land-use conversion, and an extreme climate change scenario (CCSM4.0, RCP 8.5) for 2050, which assumed zero change from human activities. To assess both potential threats, we compared the estimated annual rates of species loss (i.e., range shifts) affecting each species. Deforestation loss for all species averaged approximately 71 km2/year, while potential climate-attributed loss was almost 21 km2/year. Moreover, annual area loss rates due to deforestation were significantly higher than those attributed to climate-change (P < 0.01). However, projections into the future scenario show evidence of diverging displacement patterns, indicating the potential formation of novel ecosystems, which is consistent with other species assemblage predictions as result of climate change. Furthermore, we provide recommendations for management and conservation, prioritizing the most threatened species such as Albizia multiflora, Ceiba trichistandra, and Cochlospermum vitifolium.

Los bosques secos neotropicales son reconocidos como uno de los ecosistemas más amenazados del mundo. La acelerada pérdida de cobertura vegetal de estos bosques ha ocasionado que, en la actualidad, se encuentren restringidos a una pequeña fracción de su área de distribución histórica. Conocer su diversidad biológica, así como cuáles son los factores que controlan el funcionamiento y la estructura de estos bosques, resulta prioritario para poder desarrollar acciones de conservación efectivas. Pese a que el esfuerzo dedicado al estudio y conocimiento de estos bosques no es comparable al de otros bosques de la región, especialmente a las pluviselvas húmedas, los trabajos desarrollados han permitido describir una buena parte de su diversidad florística en amplias regiones del Neotrópico, constatar el elevado nivel de endemicidad de su flora, obtener algo de información sobre los factores que determinan su estructura y funcionamiento, así como esbozar cuáles pueden ser las causas que los están empujando a la desaparición. En este trabajo se recogen los avances en el conocimiento de los ecosistemas forestales que se desarrollan bajo condiciones climáticas secas en la región del Pacífico Ecuatorial al tiempo que se definen los vacíos de información existente. Finalmente evaluamos las principales amenazas y el grado de protección de estos bosques en el Pacífico Ecuatorial, así como las implicaciones que tiene el conocimiento de estos ecosistemas sobre su conservación. Las principales conclusiones del presente trabajo nos muestran que los bosques tropicales estacionales secos (BTES) de la región Pacífico Ecuatorial están razonablemente bien conocidos en términos florísticos, al menos en el componente conformado por las especies leñosas, aunque el conocimiento sobre sus arbustos y hierbas es muy pobre. En cuanto al funcionamiento de estos bosques hay pocos estudios que permitan entender bien su dinámica. A pesar de que los BTES del Pacífico Ecuatorial son un hábitat muy original y refugio de una diversidad única, la protección actual es poco eficiente y sólo abarca el 5% del total del área forestal remanente. Esto, sumado a la fuerte presión que estos bosques soportan debido a su transformación para otros usos, convierte a los BTES del Pacífico Ecuatorial en un área prioritaria de investigación y en una región clave en dónde centrar los esfuerzos de conservación a nivel nacional e internacional. Neotropical dry forests are recognized as one of the world’s most threatened ecosystems. At present, the accelerating loss of plant cover in these forests has caused that are restricted to a small fraction of their historic range. A better understanding of their biological diversity and the factors that control the function and structure of dry forests is a priority to develop effective conservation actions. Despite the efforts devoted to the study and knowledge of dry forests are not comparable to those in other forests of the region, especially rain forests, the work done to date has allowed describing a good part of their floristic diversity over large regions of the Neotropics, confirming the high levels of endemism of their flora, elucidating some of the factors that determine their structure, and understanding the likely causes that are driving some species to extinction. This paper reflects the progress in knowledge of dry forest ecosystems in the Ecuadorian Pacific region, at the time that it identifies existing information gaps, and evaluates the main threats and the degree of protection that these forests receive, and the implications that the current knowledge of these ecosystems may have for their conservation. The main conclusions of this study show that seasonally tropical dry forests (STDF) of the Ecuadorian Pacific region are reasonably well known in floristic terms, at least the woody species, yet other taxa such as shrubs and herbs are still poorly known. Regarding the functionality of dry forests, few studies have been conducted to understand their dynamic. The Ecuadorian Pacific region is an original habitat and refuge for a unique diversity, however the current protection is inefficient and only covers 5% of the total remaining forest. This, together with the intense anthropogenic pressure that these forests support, makes the Ecuadorian Pacific STDF a priority area of research and a key region to focus conservation national and international efforts. El presente trabajo se ha realizado gracias a la financiación de los Proyectos A/024796/09 y A/030244/10 de la Agencia Española de Cooperación Internacional para el Desarrollo. Además gracias al aporte de la Beca de doctorado SENESCYT 2008-2.