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Background: Soil seed banks play an important role in post-disturbance regeneration and succession of species from different successional stages. Questions: 1) What is the most effective method for determining the composition and structure of the soil seed bank of Andean forests? 2) What is the composition and structure of soil seed banks in old-growth forest and shrubland sites in the Andean montane tropical forest of Colombia? Study site: Andean forest, Pamplona, Norte de Santander, Colombia Methods: We surveyed the soil seed bank in two successional stages of Andean forest and examined its structure using two sampling methods: direct separation and germination. Results: Soil seed bank density was higher (18-fold in old-growth forest and 666-fold in shrubland) with the direct separation method than with germination; however, under the germination method, we found four species that we did not detect through the direct separation method. Soil seed banks from shrublands were mainly dominated by species from disturbed areas (91 %), while those from the old-growth forest presented early, intermediate and late species; e.g., Miconia summa, Myrsine dependens and Solanum sp., respectively. In the old-growth forest (especially for late species), density increased with depth. This pattern was not observed in shrubland. Seeds obtained by using the direct separation method presented low (< 7 %) viability. Conclusion:We consider the two methods to be complementary and recommend the use of both for a thorough characterization of soil seed banks from Andean forests. At different successional stages in the Colombian Andean forest, the soil seed bank may contain early, intermediate and late species, and it therefore plays an important role in the regeneration of this threatened ecosystem. Key words: secondary successional, Colombia, germination method, direct separation method, seed viability. Bancos de Semillas en dos Estadios Sucesionales de Bosque Andino en el Noreste de Colombia ResumenAntecedentes: Los bancos de semillas del suelo juegan un papel importante en la regeneración de especies de diferentes etapas de sucesión. Preguntas: 1) ¿Cuál es el método más eficaz para la descripción de la composición y la estructura del banco de semillas del suelo de los bosques andinos? y 2) ¿Cómo es la composición y estructura de los bancos de semillas del suelo en un bosque primario y un matorral en el bosque andino en Colombia? Sitio de estudio: Bosque andino en Pamplona, Norte de Santander, Colombia Métodos: Se estudiaron el banco de semillas del suelo en dos etapas de sucesión de bosque andino y se examinó la estructura mediante dos métodos de muestreo: separación directa y la germinación. Resultados: La densidad del banco de semillas en el suelo fue mayor (18 veces en bosques primarios y 666 veces en matorral) con el método de separación directa que con el método de germinación; Sin embargo, bajo el méto-do de germinación, se encontraron cuatro especies que no detectamos a través del método de separación directa. Los banco...

<p><strong>Background: </strong>Climate change will increase temperature and reduce rainfall across temperate forests of Mexico. This can alter tree establishment dynamics within forest and in neighbouring man-made clearings.</p><p><strong>Hypotheses:</strong> Climate change will reduce emergence and survival of tree seedlings, and surviving plants will display functional responses matching with these changes. These effects should be more noticeable in clearings due to the lack of canopy cover.</p><p><strong>Studied species</strong>: <em>Quercus eduardii</em> (Fagaceae, section <em>Lobatae</em>) an oak species endemic to Mexico.</p><p><strong>Study site and years of study</strong>: Tree growing season 2015-2016 (rainy season) in a mature oak forest and a neighbouring clearing in Sierra de Álvarez, state of San Luis Potosí.</p><p><strong>Methods: </strong>In both habitats, we established control plots (under current climatic conditions) and climate change simulation plots (increased temperature and reduced rainfall). At the beginning of the growing season, we sowed acorns of <em>Q. eduardii</em> in these plots and monitored the emergence, survival and growth of seedlings. At the end of the growing season, we assessed functional responses on surviving seedlings.</p><p><strong>Results:</strong> Seedling emergence and survival were lower in climate change plots from both habitats. However, differences in survival between climate treatments were larger within the forest. Seedlings from climate change plots displayed functional responses indicating higher levels of thermal and water stress.</p><p><strong>Conclusions: </strong>This study indicates that climate change will constrain tree recruitment in Mexican oak forests. However, contrary to our expectations, it seems that these effects will be higher within forests than in man-made clearings.</p>