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Abstract Ecosystem models offer a rigorous way to formalize scientific theories and are critical to evaluating complex interactions among ecological and biogeochemical processes. In addition to simulation and prediction, ecosystem models are a valuable tool for testing hypotheses about mechanisms and empirical findings because they reveal critical internal processes that are difficult to observe directly.However, many ecosystem models are difficult to manage and apply by scientists who lack advanced computing skills due to complex model structures, lack of consistent documentation, and low-level programming implementation, which facilitates computing but reduces accessibility.Here, we present the ‘pnetr’ R package, which is designed to provide an easy-to-manage ecosystem modeling framework and detailed documentation in both model structure and programming. The framework implements a family of widely used PnET (net photosynthesis, evapotranspiration) ecosystem models, which are relatively parsimonious but capture essential biogeochemical cycles of water, carbon, and nutrients. We chose the R programming language since it is familiar to many ecologists and has abundant statistical modeling resources. We showcase examples of model simulations and test the effects of phenology on carbon assimilation and wood production using data measured by the Environmental Measurement Station (EMS) eddy-covariance flux tower at Harvard Forest, MA.We hope ‘pnetr’ can facilitate further development of ecological theory and increase the accessibility of ecosystem modeling and ecological forecasting. 

As a supplementary or sometimes the only water source in dry regions, dew plays a critical role in the survival of organisms in such environments. The new hydrological tracer 17O-excess, with almost sole dependence on relative humidity, provides a new way to distinguish the evaporation processes and reconstruct the paleoclimate. Up to now, there is no daily dew isotope record on δ2H, δ18O, δ17O, d-excess, and 17O-excess.To fill this gap, here we collected daily dew (n=114) between July 2014 and April 2018 from three distinct climatic regions (i.e., Gobabeb-Namib Research Institute in the central Namib Desert with desert climate, Nice in France with Mediterranean climate, and Indianapolis in the central United States with humid continental climate).The isotopic composition (δ2H, δ18O, and δ17O) of dew was simultaneously analyzed using a Triple Water Vapor Isotope Analyzer (T-WVIA) based on Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) technique, and then d-excess and 17O-excess were calculated. The latitude, longitude, and elevation as well as three meteorological factors including temperature, relative humidity (RH), and vapour-pressure deficit (VPD) of the three collection sites were also provided here.This report presents daily dew isotope dataset under three different climatic regions. It is useful for researchers to use it as a data reference when studying global dew dynamics and dew formation mechanisms.