Water urbanism in Bogotá. Exploring the potentials of an interplay between settlement patterns and water management

A paradigm shift in water management is recognized as a necessary and fundamental step for adaptation to climate change and crucial for furthering sustainability. In contexts of rapid urbanization, this paradigm shift is particularly challenged since social and environmental needs often come into conflict. In Bogotá, as other Latin-American cities, demands for new housing are increasing daily, while the overall housing deficit remains an unresolved problem. Currently, the city faces the challenges to deal with the pressure to continue to urbanize flood prone areas with low-cost housing projects and simultaneously protect these areas in view of flooding, which promise to increase with the predictions of climate change. In order to contribute to context-responsive solutions to the water and housing issues, this paper investigates the shifting relations between settlement patterns, water infrastructure and landscape in Bogotá's El Tintal watershed. This sub-watershed of the Bogotá River has a rich history of formal and informal low-cost housing. The critical reading of the landscape transformation of the El Tintal has shown how the water system interventions were and can be instrumental in different stages of development. This reading was the base to elaborate design investigations that could translate to spatial adaptation measures. This paper argues that “soft” water management tools can be part of a twofold strategy to create spatial quality and provide resilience for more qualitative future urban development

Functional composition of epiphyte communities in the Colombian Andes

We identify changes in the functional composition of vascular epiphytes along a tropical elevational gradient with the aim of quantifying the role of climate in determining the assembly of epiphyte communities. We measured seven leaf functional traits (leaf area, specific leaf area, leaf dry‐matter content, leaf thickness, force to punch, stomatal density, and potential conductance index) in the 163 most abundant epiphyte species recorded across 10 sites located along an elevational gradient between 60 and 2,900 m above sea level in the Colombian Andes. We grouped the epiphyte species into seven hierarchical functional groups according to their most characteristic leaf traits. Along the elevational gradient, the two main independent leaf trait dimensions that distinguished community assemblages were defined primarily by leaf area‐photosynthetic (LAPS) and mass‐carbon (LMCS) gradients. Mean annual temperature was the main determinant of species position along LAPS. In contrast, local changes in specific leaf area due to variation in the epiphytes’ relative height of attachment was the main determinant of their position along the LMCS. Our findings indicate that epiphytic plant leaves have evolved to optimize and enhance photosynthesis through a leaf area–based strategy and carbon acquisition through investments in construction costs of leaf area per unit of biomass that aim to regulate light capture and tissue development. Given that most studies of plant functional traits neglect vascular epiphytes, our quantification of the multiple dimensions of epiphyte leaf traits greatly augments our understanding of vascular plant function and adaptation to changing environments