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Showing 1 to 20 of 73 for “"nitrogen uptake"”.
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Nitrogen uptake of saprotrophic basidiomycetes and bacteria
… Beijerinckia acida und Novosphingobium nitrogenifigens etwa 1–13% ihres Stickstoffbedarfs durch N2-Fixierung decken. Wurden Diazotrophe und Basidiomyceten gemeinsam kultiviert, konnte nur von B. acida N2 fixiert und an beide Basidiomyceten übertragen werden. A. croococcum und N. …
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Nitrogen uptake and phytoplankton productivity in the changing Barents Sea
… in ocean mixing are affecting nutrient supply, uptake and cycling and will<br/>have large-scale consequences for the distribution and magnitude of primary production<br/>throughout the Arctic Ocean. The objective of this study is to quantify nitrogen<br/>uptake and phytoplankton productivity in …
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Organic nitrogen uptake by marine algae: consequences for marine ecosystem functioning and biodiversity
Dissolved organic nitrogen (DON) represents a major pool of fixed, reactive nitrogen in marine systems. It is now recognized that this pool can support primary production and the ability of some algal species to exploit DON compounds as sources of Nitrogen (N) may indicate that specific DON …
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Effect of Liquid Manure on Corn and Soybean Growth, Nitrogen Uptake, and Yields
… that should provide sufficient quantities of nitrogen (N), phosphorus (P), and potassium (K) for corn, has resulted in uneven growth and reduced grain yields. Field studies were conducted at Pearl City, Illinois, in 1983 and 1984 to evaluate the effects of manure rate, nitrification …
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Nitrogen uptake patterns by snow addition in a sub-Arctic dry heath tundra ecosystem
… implications for plant water availability and nitrogen cycling processes. Through snow fence experiments and 15N isotope labelling and simulations of carbon fluxes with the CoupModel, I found that a longer growing season positively impacted plant productivity, carbon accumulation, and nutrient …
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Water Column Ammonium Concentration and Salinity Influence Nitrogen Uptake and Growth of Spartina Alterniflora
… </em>play a<em> </em>critical role in uptake and transformation of inorganic nitrogen before it reaches coastal waters, thereby reducing the potential for eutrophication. Although nitrogen availability typically limits <em>S. alterniflora </em>growth, it may be possible to exceed the …
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Nitrate and Labeled Fertilizer Nitrogen Uptake by and Distribution in Corn (Zea Mays, L.)
Made available in DSpace on 2014-12-12T00:17:52Z (GMT). No. of bitstreams: 1 7309955.pdf: 3557996 bytes, checksum: d2ad57afc62f32020ad280417fe02da0 (MD5) Previous issue date: 1972
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Using Thermal Units to Predict Biomass Accumulation and Total Nitrogen Uptake for Cover Crops in Arkansas
… improve soil health, increase plant-available nitrogen (N), provide surface residue to prevent erosional soil loss, increase water infiltration, and increase weed suppression. Cover crops growth can be predicted using thermal days or growing degree days [GDD] similar to commodity crops such as …
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A comparative study of nitrogen uptake and nitrification rates in sub-tropical, polar and upwelling waters
… important when linking carbon export to nitrate uptake by phytoplankton. However, studies of both nitrogen uptake and nitrification rates in surface waters are rare. This thesis presents such data for the Southern Ocean and St-Helena Bay, located in the Southern Benguela upwelling system. Using …
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The effect of organic carbon and nitrogen additions on inorganic nitrogen uptake by phytoplankton and bacteria
… effects of enrichment with organic carbon and nitrogen on inorganic nitrogen partitioning between phyto- and bacterio- plankton. Strongly preferential uptake of ammonium over nitrate was observed by both the phytoplanktonic and bacterial fractions, with RPINH4 values typically between 1 and 5. …
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Physiological and Molecular Dissection of Salinity Tolerance in Arabidopsis and Maize and Nitrogen Uptake in Wheat
… we compared two genotypes with contrasting nitrogen-use-efficiency (NUE), VA08MAS-369 and VA07W-415, to dissect physiological and molecular mechanisms underlying NUE regulation. Our agronomic data revealed that line 369 maintained yield and yield-related parameters and exhibited greater NUE …
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The Effect of Preflood Nitrogen and Flood Establishment Timing on Rice Development, Nitrogen Uptake and Grain Yield
<p>Urea-N fertilizer is typically applied at the 5-leaf stage to rice (Oryza sativa L.) grown in a dry-seeded, delayed-flood production system. How long the preflood-N can be delayed without adverse effects on yield potential is poorly understood. The research objective was to determine the effects …
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Rice Grain Yield and Nitrogen Uptake and Ammonia Volatilization from Urea as Affected by Urea Amendment and Simulated Rainfall
… time and selected urea-N amendments on rice N uptake and grain yield. Two field experiments were conducted to evaluate rice growth as affected by two NBPT rates (0 and 0.89 g NBPT kg-1 urea), two nitrapyrin (NP) rates (0 and 572 g NP ha-1), and three simulated rainfall timings [no simulated …
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Yield and nitrogen uptake of broccoli (Brassica oleracea L. var italica) and soil nitrate status as influenced by rate and timing of nitrogen application
… this study were to amend the current recommended nitrogen rates for broccoli production, and to measure plant N uptake and soil nitrate status throughout the growing season in order to develop an efficient N fertilization program for this emerging industry. A preliminary study in 1985 indicated no …
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Improving the Fertilizer Value of Swine Manure: In-Depth Study of Nitrogen Transformations in Soils, Corn Nitrogen Uptake, and Swine Diet Manipulation to Optimize Manure as a Resource for Agriculture
Soil extractable P levels (0--30 cm) after corn harvest were increased by 1.5 mg kg-1 Bray P1. Nitrate-N present in manured soils (0--90 cm) after harvest did not differ from soils receiving the same inorganic N rates, and averaged 17, 24 and 30 kg NO3--N for the low, medium, and high CP manures, …
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Nitrogen loss inhibitors in intensively managed winter wheat
Several potential pathways exist for significant nitrogen loss from nitrogen fertilizer applied to winter wheat in Virginia. A number of materials have been previously identified which inhibit steps in one or more of these loss pathways. Ammonium polyphosphate, ammonium thiosulfate, dicyandiamide, …
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Nutrient and Carbon Dynamics in the Chesapeake Bay Outflow Plume and Their Effect on the Coastal Ocean Environment
… primary productivity rates, and the uptake of nitrogen using stable isotopes, I identified three different plume types that differentially provided nutrients and created conditions either suitable or unsuitable for primary productivity in the coastal zone. A jet-like plume, where …
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