Globally, soil organic matter (SOM) contains more than three times as much carbon as either the atmosphere or terrestrial vegetation. Yet it remains largely unknown why some SOM persists for millennia whereas other SOM decomposes readily—and this limits our ability to predict how soils will respond to climate change. Recent analytical and experimental advances have… More

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Accurate estimates of leaf area index (LAI) and leaf angle distribution (LAD) are important for estimating the exchange of energy and gases in vegetative canopies. Direct estimates of LAI and LAD are laborious, time consuming and often times destructive. Stewart and Dwyer [Agric. For. Meteorol. 66 (1993) 247] introduced a mathematical method to calculate LAI… More

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High evaporative demand and periodic drought characterize the growing season in midwestern grasslands relative to deciduous forests of the eastern US, and predicted climatic changes suggest that these climatic extremes may be exacerbated. Despite this less than optimal environment for tree seedling establishment, deciduous trees have expanded into adjacent tallgrass prairie within the last century… More

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Mapping and monitoring of leaf area index (LAI) is important for spatially distributed modeling of vegetation productivity, evapotranspiration, and surface energy balance. Global LAI surfaces will be an early product of the MODIS Land Science Team, and the requirements for LAI validation at selected sites have prompted interest in accurate LAI mapping at a more… More

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In tallgrass prairie, plant species interactions regulated by their associated mycorrhizal fungi may be important forces that influence species coexistence and community structure; however, the mechanisms and magnitude of these interactions remain unknown. The objective of this study was to determine how interspecific competition, mycorrhizal symbiosis, and their interactions influence plant community structure. We conducted… More

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Substantial research seeks to improve estimates of ecosystem processes and fluxes at a range of scales, notably from the stand scale (<1 km2) using ecosystem physiology and eddy covariance techniques, to the landscape (∼102 km2) and global (108 km2) scales using a variety of modeling and data acquisition approaches. One approach uses remotely sensed ecosystem… More

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To address the need for a high quality data set based upon field observations suitable for parameterization, calibration, and validation of terrestrial biosphere models, we have developed a comprehensive global database on net primary productivity (NPP). We have compiled field measurements of biomass and associated environmental data for multiple study sites in major grassland types… More

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