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Trade‐Offs Between Carbon and Water Fluxes Along a Land Use Intensity Gradient in Southeast Asian Forests and PlantationsNARA Subscribed
Land use intensity (LUI) significantly influences the biophysical and biogeochemical properties of the global landscape. The impact of LUI is exceptionally strong in Southeast Asia (SEA), where forests are increasingly being replaced by intensively managed plantations. Despite these transformations, comprehensive studies on how different LUI regulate carbon, energy, and water fluxes in this region remain scarce. In this study,...
Comparison of ecosystem-scale carbon fluxes at agroforestry and adjacent monocropping sites in GermanyNARA Subscribed
Agroforestry (AF) systems, such as short rotation alley-cropping systems are considered to improve carbon (C) sequestration compared to conventional land use without trees, while also providing environmental co-benefits, such as improved biodiversity and reduced soil erosion. Supporting ecosystem-scale measurements of C uptake are, however, largely lacking. In this study, we aim to quantify the continuous C uptake of four temp...
Decoding autumn phenology: Unraveling the link between observation methods and detected environmental cuesNARA Subscribed
Leaf coloring and fall mark the end of the growing season (EOS), playing essential roles in nutrient cycling, resource allocation, ecological interactions, and as climate change indicators. However, understanding future changes in autumn phenology is challenging due to the multitude of likely environmental cues and substantial variations in timing caused by different derivation methods. Yet, it remains unclear whether these tw...
Effects of competition reduction on intra-annual radial growth of European beech (Fagus sylvatica L.) at stem base and crown baseNARA Subscribed
Key message In beech stands, thinning affects growth differently along tree stems, with higher and longer duration increment at stem base than at crown base while unmanaged stands depict opposite patterns. Abstract Forest management affects individual tree growth dynamics at different levels of the tree bole. Here, we assessed stem-growth patterns as a function of bole height (stem base and crown base) and competition reductio...
Global maps of soil temperatureNARA Subscribed
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1‐km 2 r...
Uncovering the critical soil moisture thresholds of plant water stress for European ecosystemsNARA Subscribed
Understanding the critical soil moisture (SM) threshold (θ crit ) of plant water stress and land surface energy partitioning is a basis to evaluate drought impacts and improve models for predicting future ecosystem condition and climate. Quantifying the θ crit across biomes and climates is challenging because observations of surface energy fluxes and SM remain sparse. Here, we used the latest database of eddy covariance measur...
Ecosystem transpiration and evaporation: Insights from three water flux partitioning methods across FLUXNET sitesNARA Subscribed
We apply and compare three widely applicable methods for estimating ecosystem transpiration ( T ) from eddy covariance (EC) data across 251 FLUXNET sites globally. All three methods are based on the coupled water and carbon relationship, but they differ in assumptions and parameterizations. Intercomparison of the three daily T estimates shows high correlation among methods ( R between .89 and .94), but a spread in magnitudes o...
Climate and soils together regulate photosynthetic carbon isotope discrimination within C 3 plants worldwideNARA Subscribed
Aim Within C 3 plants, photosynthesis is a balance between CO 2 supply from the atmosphere via stomata and demand by enzymes within chloroplasts. This process is dynamic and a complex but crucial aspect of photosynthesis. We sought to understand the spatial pattern in CO 2 supply–demand balance on a global scale, via analysis of stable isotopes of carbon within leaves (Δ 13 C), which provide an integrative record of CO 2 drawd...
This paper examines long‐term eddy covariance data from 18 European and 17 North American and Asian forest, wetland, tundra, grassland, and cropland sites under non‐water‐stressed conditions with an empirical rectangular hyperbolic light response model and a single layer two light‐class carboxylase‐based model. Relationships according to ecosystem functional type are demonstrated between empirical and physiological parameters,...