Resumen

Bamboos have been consistently excluded from ecological studies and monitoring efforts, particularly in the Neotropics. However, the extreme abundance, diversity and unique physiology of bamboos make them strong competitors, with high potential to influence the structure and functioning of the surrounding trees and forests. Therefore, the role of bamboos should be better explored, characterized, and monitored. In my PhD dissertation I combined multiple approaches (remote sensing, population census, functional ecology and taxonomy) to increase our understanding of bamboo ecology, physiology, and systematics and obtain different perspectives of the interaction between bamboo and trees. I did this across a range of critical ecosystems from the lowland Amazonian forests to the high-elevation cloud forests and puna in the Peruvian Andes. In my dissertation, I developed a monitoring protocol with specific guidelines to facilitate and promote bamboo data collection. I used this protocol to carry out a bamboo census in seven 1-ha permanent plots along an elevation transect in the Andes. I found an overall negative association between bamboo abundance and total tree basal area across the gradient, driven mainly by reduced tree density. To study the effect of bamboo on forest functioning along an entire bamboo life cycle, I used remote sensing proxies of productivity and water content obtained from a time-series of Landsat images (1989-2017). I found a strong influence of bamboo phenology and life-stage in the long-term and seasonal functioning of Amazonian bamboo-dominated forests. In particular, bamboo exerts a strong control over local water availability which may be a mechanism for modulation of forest functioning and composition. To further understand bamboo physiology, I collected data on leaf functional traits and tolerance to heat and drought of 22 woody bamboo species along the Amazon-Andes transect. I found that bamboo functional traits show different values and elevational trends compared with other plants; indeed, bamboo shows traits indicative of an acquisitive resource strategy throughout the gradient. Low elevation species show low tolerance to drought and high tolerance to temperature, and the opposite in high elevation species. Nevertheless, low elevation species may be more vulnerable to global warming because they are more likely to experience temperatures closer to their tolerance threshold. Climatic tolerances are highly related with species distributions, and are better predicted by mean annual temperature and precipitation seasonality than by the combination of other leaf traits. Finally, to contribute to deciphering bamboo phylogeny and diversity, I described two new species of Chusquea subgenus Swallenochloa. Overall, on my dissertation I highlight the important role of bamboos in shaping forest structure, functioning and diversity, and I reveal the physiological and morphological characteristics that may confer bamboo an advantage to thrive in multiple environments. Future forest projections and conservation measurements rely on detailed knowledge of forest functioning, understanding bamboo is an essential step to that end