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Showing 1 to 12 of 12 for “"Nitrogen fixation rates"”.
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Effects of light and temperature on nitrogen-fixation rates in arable soils and seasonal fluctuations in nitrogen-fixation rates in arable soils
Nitrogen-fixation rates were determined by C₂H₂ reduction in intact cores taken from the top 0-1 cm of two soils. The cores were moistened and incubated under varying light (0-88 W•m⁻²) and temperature (7.5- 39.5ºC) conditions at four different times of the year to determine the effects of day …
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Estimating Nitrogen Fixation Rates, Importance, and Short-Term Efficiency in Small, Temperate Reservoirs Using Delta15N Techniques
<p>Nitrogen (N2) fixation can give certain species of cyanobacteria a competitive advantage in lake and reservoir phytoplankton. These species of cyanobacteria, along with others that cannot fix N2, can form toxic compounds that impair water quality when present in high concentrations. N2 fixation …
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Factors Affecting Nitrogen Fixation Rates in Termites (Isoptera: Rhinotermitidae: <i>Reticulitermes</i>) and Termite Nitrogen Contributions of Forest Ecosystems
… host symbiotic bacteria that fix atmospheric nitrogen, which makes termites important in the biogeochemical cycling of nitrogen in ecosystems. The objective of this study was to estimate annual nitrogen contributions by termites by examining seasonal rates of nitrogen fixation, seasonal …
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Investigating the role of trichodesmium spp. in the oceanic nitrogen cycle through observations and models
The nitrogen fixation and abundance of Trichodesmium colonies and their connections with physical processes were investigated through Video Plankton Recorder (VPR) and other observations collected in fall 2010 and spring 2011 in the western subtropical–tropical North Atlantic. A data processing …
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Investigating the role of Trichodesmium spp. in the oceanic nitrogen cycle through observations and models
This work concerns the nitrogen fixation and abundance of Trichodesmium colonies in the western subtropical-tropical North Atlantic and their connections with physical processes. Data were collected in fall 2010 and spring 2011, primarily using the Video Plankton Recorder (VPR). A data processing …
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Biological nitrogen fixation in a nitrogen limited tropical lake, Lake Chapala, Mexico.
… my study was to quantify the rate of biological nitrogen fixation in Lake Chapala, Mexico. Lake Chapala is the largest lake in Mexico. It is an ancient, tropical lake which is shaped in an east-west culde-sac with the inflow and outflow at the eastern end. Previous work showed low available …
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Drivers And Dynamics Of Harmful Algal Blooms: Understanding Nitrogen Fixation And Bloom Composition In Minnesota Temperate Lakes
… partially reflect an underestimation of internal nitrogen contributions from biological nitrogen fixation, leading to an incomplete understanding of nitrogen dynamics in freshwater systems. Nitrogen fixation by cyanobacteria and heterotrophic bacteria can supplement nitrogen availability, …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
Nitrogen (N) is a primary limiting nutrient in all ecosystems. Therefore, a thorough understanding of N cycling processes in forest ecosystems is required to minimize N losses to fire, harvesting, and other forms of land management. The influence of fire, fire exclusion and forest restoration …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
Nitrogen (N) is a primary limiting nutrient in all ecosystems. Therefore, a thorough understanding of N cycling processes in forest ecosystems is required to minimize N losses to fire, harvesting, and other forms of land management. The influence of fire, fire exclusion and forest restoration …
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Ocean biogeochemistry in the northern Gulf of Mexico, the East/Japan Sea, and the South Pacific with a focus on denitrification
Ocean nitrogen fixation and denitrification are crucial nitrogen source and sink mechanisms for the global ocean environment. While recent studies have reported that oceanic denitrification has increased over the last few decades, others have suggested that global ocean nitrogen fixation rates have …
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Optimizing soybean water use and nitrogen fixation to improve productivity under climate change
… studies have yet examined the effect of VPD on nitrogen fixation, likely due to difficulties of taking non-invasive, real-time measurements.A common technique for monitoring nitrogen fixation rates non-destructively is the acetylene reduction assay (ARA), which has received critiques due to …
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The Biogeochemistry of iron, zinc and cobalt in the Atlantic Ocean: the Atlantic Meridional Transect and UK GEOTRACES sections
… in enzymatic processes such as inorganic carbon, nitrogen and phosphorus acquisition. The distributions and biogeochemistries of iron, zinc and cobalt therefore, have the potential to impact upon the global carbon cycle and hence climate. This research involves investigations into the …