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Eddy covariance measurements reveal a decreased carbon sequestration strength 2010–2022 in an African semiarid savannaNARA Subscribed
Monitoring the changes of ecosystem functioning is pivotal for understanding the global carbon cycle. Despite its size and contribution to the global carbon cycle, Africa is largely understudied in regard to ongoing changes of its ecosystem functioning and their responses to climate change. One of the reasons is the lack of long‐term in situ data. Here, we use eddy covariance to quantify the net ecosystem exchange (NEE) and it...
Increasing global ecosystem respiration between 1982 and 2015 from Earth observation‐based modellingNARA Subscribed
Aim Earth observation‐based estimates of land–atmosphere exchange of carbon are essential for understanding the response of the terrestrial biosphere to climatic change and other anthropogenic forcing. Temperature, soil water content and gross primary production are the main drivers of ecosystem respiration (R eco ), and the main aims of this study are to develop an R eco model driven by long‐term global‐scale Earth observatio...
Contrasting ecosystem vegetation response in global drylands under drying and wetting conditionsNARA Subscribed
Increasing aridity is one major consequence of ongoing global climate change and is expected to cause widespread changes in key ecosystem attributes, functions, and dynamics. This is especially the case in naturally vulnerable ecosystems, such as drylands. While we have an overall understanding of past aridity trends, the linkage between temporal dynamics in aridity and dryland ecosystem responses remain largely unknown. Here,...
Carbon uptake in Eurasian boreal forests dominates the high‐latitude net ecosystem carbon budgetNARA Subscribed
Arctic‐boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic‐boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003–2015) vegetation gross primary productivity (G...
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...
Statistical upscaling of ecosystem CO 2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertaintiesNARA Subscribed
The regional variability in tundra and boreal carbon dioxide (CO 2 ) fluxes can be high, complicating efforts to quantify sink‐source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO 2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we com...
A physiology‐based Earth observation model indicates stagnation in the global gross primary production during recent decadesNARA Subscribed
Earth observation‐based estimates of global gross primary production (GPP) are essential for understanding the response of the terrestrial biosphere to climatic change and other anthropogenic forcing. In this study, we attempt an ecosystem‐level physiological approach of estimating GPP using an asymptotic light response function (LRF) between GPP and incoming photosynthetically active radiation (PAR) that better represents the...
Revealing turning points in ecosystem functioning over the Northern Eurasian agricultural frontierNARA Subscribed
The collapse of the Soviet Union in 1991 has been a turning point in the World history that left a unique footprint on the Northern Eurasian ecosystems. Conducting large scale mapping of environmental change and separating between naturogenic and anthropogenic drivers is a difficult endeavor in such highly complex systems. In this research a piece‐wise linear regression method was used for breakpoint detection in Rain‐Use Effi...
Global‐scale mapping of changes in ecosystem functioning from earth observation‐based trends in total and recurrent vegetationNARA Subscribed
Aim To evaluate trend analysis of earth observation ( EO ) dense time series as a new way of describing and mapping changes in ecosystem functioning at regional to global scales. Spatio‐temporal patterns of change covering 1982–2011 are discussed in the context of changes in land use and land cover ( LULCC ). Location Global. Methods This study takes advantage of the different phenological cycles of recurrent vegetation (herba...
Ecosystem properties of semiarid savanna grassland in West Africa and its relationship with environmental variabilityNARA Subscribed
The Dahra field site in Senegal, West Africa, was established in 2002 to monitor ecosystem properties of semiarid savanna grassland and their responses to climatic and environmental change. This article describes the environment and the ecosystem properties of the site using a unique set of in situ data. The studied variables include hydroclimatic variables, species composition, albedo, normalized difference vegetation index (...
Land‐atmosphere exchange of methane from soil thawing to soil freezing in a high‐ A rctic wet tundra ecosystemNARA Subscribed
The land‐atmosphere exchange of methane ( CH 4 ) and carbon dioxide ( CO 2 ) in a high‐ A rctic wet tundra ecosystem ( R ylekærene) in Z ackenberg, north‐eastern G reenland, was studied over the full growing season and until early winter in 2008 and from before snow melt until early winter in 2009. The eddy covariance technique was used to estimate CO 2 fluxes and a combination of the gradient and eddy covariance methods was u...
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