In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement...

Wildfire is an essential earth‐system process, impacting ecosystem processes and the carbon cycle. Forest fires are becoming more frequent and severe, yet gaps exist in the modeling of fire on vegetation and carbon dynamics. Strategies for reducing carbon dioxide (CO 2 ) emissions from wildfires include increasing tree harvest, largely based on the public assumption that fires burn live forests to the ground, despite observati...

Multifactor experiments are often advocated as important for advancing terrestrial biosphere models ( TBM s), yet to date, such models have only been tested against single‐factor experiments. We applied 10 TBM s to the multifactor Prairie Heating and CO 2 Enrichment ( PHACE ) experiment in Wyoming, USA . Our goals were to investigate how multifactor experiments can be used to constrain models and to identify a road map for mod...

Determining whether the terrestrial biosphere will be a source or sink of carbon (C) under a future climate of elevated CO 2 ( eCO 2 ) and warming requires accurate quantification of gross primary production ( GPP ), the largest flux of C in the global C cycle. We evaluated 6 years (2007–2012) of flux‐derived GPP data from the Prairie Heating and CO 2 Enrichment ( PHACE ) experiment, situated in a grassland in Wyoming, USA . T...

Increases in atmospheric nitrogen deposition (N dep ) can strongly affect the greenhouse gas ( GHG ; CO 2 , CH 4 , and N 2 O) sink capacity of grasslands as well as other terrestrial ecosystems. Robust predictions of the net GHG sink strength of grasslands depend on how experimental N loads compare to projected N dep rates, and how accurately the relationship between GHG fluxes and N dep is characterized. A literature review r...

Livestock manure is applied to rangelands as an organic fertilizer to stimulate forage production, but the long‐term impacts of this practice on soil carbon (C) and greenhouse gas ( GHG ) dynamics are poorly known. We collected soil samples from manured and nonmanured fields on commercial dairies and found that manure amendments increased soil C stocks by 19.0 ± 7.3 Mg C ha −1 and N stocks by 1.94 ± 0.63 Mg N ha −1 compared to...

Eddy covariance nighttime fluxes are uncertain due to potential measurement biases. Many studies report eddy covariance nighttime flux lower than flux from extrapolated chamber measurements, despite corrections for low turbulence. We compared eddy covariance and chamber estimates of ecosystem respiration at the GLEES Ameriflux site over seven growing seasons under high turbulence [summer night mean friction velocity (u*) = 0.7...

Understanding the potential for greenhouse gas ( GHG ) mitigation in agricultural lands is a critical challenge for climate change policy. This study uses the DAYCENT ecosystem model to predict GHG mitigation potentials associated with soil management in Chinese cropland systems. Application of ecosystem models, such as DAYCENT , requires the evaluation of model performance with data sets from experiments relevant to the clima...

Currently, forests in the northeastern United States are net sinks of atmospheric carbon. Under future climate change scenarios, the combined effects of climate change and nitrogen deposition on soil decomposition, aboveground processes, and the forest carbon balance remain unclear. We applied carbon stock, flux, and isotope data from field studies at the Harvard forest, Massachusetts, to the ForCent model, which integrates ab...

Predicted responses of transpiration to elevated atmospheric CO 2 concentration ( eCO 2 ) are highly variable amongst process‐based models. To better understand and constrain this variability amongst models, we conducted an intercomparison of 11 ecosystem models applied to data from two forest free‐air CO 2 enrichment ( FACE ) experiments at Duke University and Oak Ridge National Laboratory. We analysed model structures to ide...

Decomposition is a large term in the global carbon budget, but models of the earth system that simulate carbon cycle‐climate feedbacks are largely untested with respect to litter decomposition. We tested the litter decomposition parameterization of the community land model version 4 ( CLM 4), the terrestrial component of the community earth system model, with data from the long‐term intersite decomposition experiment team ( LI...

Net ecosystem productivity ( NEP ) was measured on shortgrass steppe ( SGS ) vegetation at the USDA C entral P lains E xperimental R ange in northeastern C olorado from 2001 to 2003. Large year‐to‐year differences were observed in annual NEP , with >95% of the net carbon uptake occurring during M ay and J une. Low precipitation during the 2002 A pril to J une time period greatly reduced annual net carbon uptake. Large precipit...

Ecology Letters (2011) 14 : 939–947 Abstract Tropical rain forests play a dominant role in global biosphere‐atmosphere CO 2 exchange. Although climate and nutrient availability regulate net primary production (NPP) and decomposition in all terrestrial ecosystems, the nature and extent of such controls in tropical forests remain poorly resolved. We conducted a meta‐analysis of carbon‐nutrient‐climate relationships in 113 sites...

One of the major concerns about global warming is the potential for an increase in decomposition and soil respiration rates, increasing CO 2 emissions and creating a positive feedback between global warming and soil respiration. This is particularly important in ecosystems with large belowground biomass, such as grasslands where over 90% of the carbon is allocated belowground. A better understanding of the relative influence o...

Decomposition is a critical process in global carbon cycling. During decomposition, leaf and fine root litter may undergo a later, relatively slow phase; past long‐term experiments indicate this phase occurs, but whether it is a general phenomenon has not been examined. Data from Long‐term Intersite Decomposition Experiment Team, representing 27 sites and nine litter types (for a total of 234 cases) was used to test the freque...

As atmospheric CO 2 increases, ecosystem carbon sequestration will largely depend on how global changes in climate will alter the balance between net primary production and decomposition. The response of primary production to climatic change has been examined using well‐validated mechanistic models, but the same is not true for decomposition, a primary source of atmospheric CO 2 . We used the Long‐term Intersite Decomposition...

Climate and litter quality are primary drivers of terrestrial decomposition and, based on evidence from multisite experiments at regional and global scales, are universally factored into global decomposition models. In contrast, soil animals are considered key regulators of decomposition at local scales but their role at larger scales is unresolved. Soil animals are consequently excluded from global models of organic mineraliz...

The ongoing changes in the global climate expose the world's ecosystems not only to increasing CO 2 concentrations and temperatures but also to altered precipitation ( P ) regimes. Using four well‐established process‐based ecosystem models (LPJ, DayCent, ORCHIDEE, TECO), we explored effects of potential P changes on water limitation and net primary production (NPP) in seven terrestrial ecosystems with distinctive vegetation ty...