Riverine ecosystems are linked to their watersheds, and both land use and physiographic environmental conditions influence nutrient dynamics and water quality. We assessed aquatic nutrients and their relationship with land use and physiographic conditions at multiple spatial scales in the Brazos River watershed (Texas, USA) to examine the interactions between land use and physiography and their...

By assessing current leaf litter nutrient dynamics, we may be able to predict responses of nutrient cycling in tropical ecosystems to future environmental change. The goal of this study was to assess whether nutrient cycling is related to seasonal variation in rainfall in a wet tropical forest. We examined leaf litter of an old-growth tropical rain forest in N.E. Costa Rica over a 4-year period...

Introduction Aquatic ecosystems have been fertile ground for understanding the extent to which animals can alter nutrient cycling. Although animals have been included in ecosystem models for years (for example, Teal, 1962), it is only more recently that investigators have looked at animals, either as individuals, single species, or assemblages, as agents regulating nutrient cycling (Kitchell et...

Predicting and controlling the behaviour of microbial ecosystems demands a fundamental understanding of the factors controlling their dynamics. In the natural environment microbes typically live in small local populations with limited and unpredictable nutrient supply and high death rates. Here, we show that these conditions can produce oscillations in microbial population dynamics, even for a ...

Abstract Gloriosa superba L. is a recently introduced tropical species in Argentina, cultivated as cut flower. It extremely important to know the nutritional demands of crop provide optimal amounts nutrients at each stage, achieving quality and good yield flowers, reducing production costs environmental impact. The objective this work was determine dynamics nutrient absorption cultivation G. fo...

The link between compensatory dynamics and regime shifts is not well understood. We analyse a regime shift in phytoplankton in a large lake with respect to: (1) environmental forcing and (2) the type of dynamics (compensatory or synchronous) between phytoplankton groups. The regime shift in phytoplankton was related to gradual changes in nutrient levels, but unrelated to an almost concurrent sh...

Self-organized pattern formation is observed in bacterial colony growth. The recently reported knotted-branching pattern of the Bacillus circulans colony consists of the trajectories of aggregates which grow, move, and reproduce simultaneously. We modeled these processes by combining a reaction diffusion system of nutrient dynamics, nucleation theory for aggregate generation, and individual bas...

Nutrient cycling is a key process linking organisms in ecosystems. This is especially apparent in stream environments in which nutrients are taken up readily and cycled through the system in a downstream trajectory. Ecological stoichiometry predicts that biogeochemical cycles of different elements are interdependent because the organisms that drive these cycles require fixed ratios of nutrients...