Despite their low contribution to forest carbon stocks, lianas (woody vines) play an important role in the carbon dynamics of tropical forests. As structural parasites, they hinder tree survival, growth and fecundity; hence, they negatively impact net ecosystem productivity and long‐term carbon sequestration. Competition (for water and light) drives various forest processes and depends on the local abundance of resources over time. However, evaluating the relative role of resource availability on the interactions between lianas and trees from empirical observations is particularly challenging. Previous approaches have used labour‐intensive and ecosystem‐scale manipulation experiments, which are infeasible in most situations. We propose to circumvent this challenge by evaluating the uncertainty of water and light capture processes of a process‐based vegetation model (ED2) including the liana growth form. We further developed the liana plant functional type in ED2 to mechanistically simulate water uptake and transport from roots to leaves, and start the model from prescribed initial conditions. We then used the PEcAn bioinformatics platform to constrain liana parameters and run uncertainty analyses. Baseline runs successfully reproduced ecosystem gas exchange fluxes (gross primary productivity and latent heat) and forest structural features (leaf area index, aboveground biomass) in two sites (Barro Colorado Island, Panama and Paracou, French Guiana) characterized by different rainfall regimes and levels of liana abundance. Model uncertainty analyses revealed that water limitation was the factor driving the competition between trees and lianas at the drier site (BCI), and during the relatively short dry season of the wetter site (Paracou). In young patches, light competition dominated in Paracou but alternated with water competition between the wet and the dry season on BCI according to the model simulations. The modelling workflow also identified key liana traits (photosynthetic quantum efficiency, stomatal regulation parameters, allometric relationships) and processes (water use, respiration, climbing) driving the model uncertainty. They should be considered as priorities for future data acquisition and model development to improve predictions of the carbon dynamics of liana‐infested forests. Synthesis. Competition for water plays a larger role in the interaction between lianas and trees than previously hypothesized, as demonstrated by simulations from a process‐based vegetation model.

DIBBs Brown Dog is a recent cyberinfrastructure effort which aims to create two new services to aid users in the searching, accessing, and usage of digital data and provide these services in a manner that is as broadly and easily accessible as possible. At its lowest level, the Data Access Proxy (DAP) providing file format conversion capabilities and the Data Tilling Service (DTS) providing content based extractions, will be accessible via a deliberately compact REST interface. On top of this a number of client libraries and applications can and are being constructed to even further reduce the overhead of accessing the provided functionality (e.g. libraries in Javascript, Python, R, Matlab and interfaces such as bookmarklets, browser extensions, and other standalone applications). At the heart of the two services, however, is their extensibility, allowing one to potentially incorporate any library or tool as a conversion or extraction component within the services towards both the leveraging of the functionality they provide as well as the preservation of the tools themselves.