Salt marshes provide many key ecosystem services that have tremendous ecological and economic value. One critical service is the removal of fixed nitrogen from coastal waters, which limits the negative effects of eutrophication resulting from increased nutrient supply. Nutrient enrichment of salt marsh sediments results in higher rates of nitrogen cycling and, commonly, a concurrent increase in...

Global climate is, in part, regulated by the effect of microbial processes on biogeochemical cycling. The nitrogen cycle, in particular, is driven by microorganisms responsible for the fixation and loss of nitrogen, and the reduction-oxidation transformations of bio-available nitrogen. Within marine systems, nitrogen availability is often the limiting factor in the growth of autotrophic organis...

Hypolithic microbial communities (i.e. cryptic microbial assemblages found on the undersides of translucent rocks) are major contributors of carbon input into the oligotrophic hyper-arid desert mineral soils of the Eastern Antarctic Dry Valleys. Here we demonstrate, for the first time, that hypolithic microbial communities possess both the genetic capacity for nitrogen fixation (i.e. the presen...

Microorganisms control key biogeochemical pathways, thus changes in microbial diversity, community structure and activity can affect ecosystem response to environmental drivers. Understanding factors that control the proportion of active microbes in the environment and how they vary when perturbed is critical to anticipating ecosystem response to global change. Increasing supplies of anthropoge...

To obtain an in-depth understanding of soil nitrogen dynamics, it is necessary to quantify a variety of simultaneously occurring gross nitrogen transformation processes. In order to do so, most studies apply 15N in a disturbed soil-microbial-root system and quantify gross rates based on the principles of 15N isotope dilution. However, this approach has several shortcomings. First, studying dist...

Rumen is a persistent and specific ecosystem consists of bacteria, protozoa and fungus where feed fermentation takes place in it. Produced Hydrogen in rumen can be used in the synthesis of the volatile fatty acids and the microbial protein and its excess would be eliminated through the production of Methane by methanogenesis. Nutritionists have tried to find ways to decrease loss and energy and...

We report changes in nitrogen cycling in Florida scrub oak in response to elevated atmospheric CO2 during the ®rst 14 months of experimental treatment. Elevated CO2 stimulated above-ground growth, nitrogen mass, and root nodule production of the nitrogen-®xing vine, Galactia elliottii Nuttall. During this period, elevated CO2 reduced rates of gross nitrogen mineralization in soil, and resulted ...

rumen is a persistent and specific ecosystem consists of bacteria, protozoa and fungus where feed fermentation takes place in it. produced hydrogen in rumen can be used in the synthesis of the volatile fatty acids and the microbial protein and its excess would be eliminated through the production of methane by methanogenesis. nutritionists have tried to find ways to decrease loss and energy and...

Field experiments are described involving nitrogen fertilizer in wheat field to research its effect on microbial quantity and enzyme activity. The results showed that 250 kg N hm applied in wheat field (1) can increase bacteria, fungi, actinomycetes quantity by 39.9%, 56.7% and 70.5% compare to 0 kg N hm. (2) Similarly, the activities of soil urease, catalase and FDA expressed 60.8%, 18.3% and ...