[1] We develop a state-space Bayesian framework to combine time-lapse geophysical data with other types of information for quantitative estimation of biogeochemical parameters during bioremediation. We consider characteristics of end products of biogeochemical transformations as state vectors, which evolve under constraints of local environments through evolution equations, and consider time-la...

Earth System Climate Models (ESCMs) are valuable tools that can be used to gain a better understanding of the climate system, global biogeochemical cycles and how anthropogenically-driven changes may affect them. Here we describe improvements made to the marine biogeochemical ecosystem component of the University of Victoria’s ESCM (version 2.9). Major changes include corrections to the code an...

Stress within tree roots may influence whole-tree responses to nutrient deficiencies or toxic ion accumulation, but the mechanisms that govern root responses to the belowground chemical environment are poorly quantified. Currently, root production is modeled using rates of forest production and stoichiometry, but this approach alone may be insufficient to forecast variability in forest response...

[1] Sea-viewing Wide Field-of-View Sensor (SeaWiFS) images from June 1998 show a surprising early summer phytoplankton bloom in southern Lake Michigan that accounted for approximately 25% of the lake’s annual gross offshore algal primary production. By combining the satellite imagery with in situ measurements of water temperature and wind velocity we show that the bloom was triggered by a brief...

The biological reduction of N(2) is catalyzed by nitrogenase, which is irreversibly inhibited by molecular oxygen. Cyanobacteria are the only diazotrophs (nitrogen-fixing organisms) that produce oxygen as a by-product of the photosynthetic process, and which must negotiate the inevitable presence of molecular oxygen with an essentially anaerobic enzyme. In this review, we present an analysis of...

A three-dimensional ocean biogeochemical model of the tropical Atlantic Ocean was run for more than half a century (1949–2000) in order to characterize the ocean biogeochemical response to variable forcing over this period. The seasonal cycle in the equatorial upwelling zone agrees reasonably well with observations and other published simulations but underestimates phytoplankton biomass under s...

The LONG TERM ECOLOGICAL RESEARCH program (L TEA) is a network of field sites used to study structure and process in natural landscapes at temporal and spatial scales of decades or centuries. The ten sites now funded by the National Science Foundation's Division of Biotic Systems and Resources, include forest, prairie, desert, and aquatic environments. Major questions are addressed at each site...