Sample records for nutrientes npk em

  1. Simple models and concepts as tools for the study of sustained soil productivity in long-term experiments. II. Crop nutrient equivalents, balanced supplies of available nutrients, and NPK triangles

    Microsoft Academic Search

    Bert H. Janssen

    2011-01-01

    Two NPK factorial trials, one in Vietnam and one in The Netherlands were (re-)analyzed to find causes of success or failure\\u000a with regard to sustained soil productivity, using the concept of crop nutrient equivalents (CNE). A (k)CNE is the quantity\\u000a of a nutrient that, under conditions of balanced nutrition, has the same effect on yield as 1 (k)g of nitrogen.

  2. Assessment and treatment of hydrocarbon inundated soils using inorganic nutrient (N-P-K) supplements: II. A case study of eneka oil spillage in Niger Delta, Nigeria.

    PubMed

    Osuji, Leo C; Egbuson, Ebitimi J; Ojinnaka, Chukwunnoye M

    2006-04-01

    Polluted soils from Eneka oil field in the Niger delta region of Nigeria were collected two months after recorded incidence of oil spillage as part of a two-site reclamation programme. The soils were taken on the second day of reconnaissance from three replicate quadrats, at surface (0-15 cm) and subsurface (15-30 cm) depths, using the grid sampling technique. Total extractable hydrocarbon content (THC) of the polluted soils ranged from 1.006 x 10(3)-5.540 x 10(4) mg/kg at surface and subsurface depths (no overlap in Standard Errors at 95% Confidence Level). Greenhouse trials for possible reclamation were later carried out using (NH(4))(2)SO(4), KH(2)PO(4) and KCl (N-P-K) fertilizer as nutrient supplements. Nitrogen as NO(3)-N and potassium were optimally enhanced at 2% (w/w) and 3% (w/w) of the N-P-K supplementation respectively. Phosphorus, which was inherently more enhanced in the soils than the other nutrients, maintained same level impact after 20 g treatment with the N-P-K fertilizer. Total organic carbon (%TOC), total organic matter (%TOM), pH and % moisture content all provided evidence of enhanced mineralization in the fertilizer treated soils. If reclamation of the crude oil inundated soils is construed as the return to normal levels of metabolic activities of the soils, then the application of the inorganic fertilizers at such prescribed levels would duly accelerate the remediation process. This would be, however, limited to levels of pollution empirically defined by such THC values obtained in this study. The data on the molecular compositional changes of the total petroleum hydrocarbon content (TPH) of the spilled-oil showed the depletion of the fingerprints of the n-paraffins, nC(8)-nC(10), and complete disappearance of C(12)-C(17) as well as the acyclic isoprenoid, pristane, all of which provided substantial evidence of degradation. PMID:16649138

  3. NPK macronutrients and microRNA homeostasis

    PubMed Central

    Kulcheski, Franceli R.; Côrrea, Régis; Gomes, Igor A.; de Lima, Júlio C.; Margis, Rogerio

    2015-01-01

    Macronutrients are essential elements for plant growth and development. In natural, non-cultivated systems, the availability of macronutrients is not a limiting factor of growth, due to fast recycling mechanisms. However, their availability might be an issue in modern agricultural practices, since soil has been frequently over exploited. From a crop management perspective, the nitrogen (N), phosphorus (P), and potassium (K) are three important limiting factors and therefore frequently added as fertilizers. NPK are among the nutrients that have been reported to alter post-embryonic root developmental processes and consequently, impairs crop yield. To cope with nutrients scarcity, plants have evolved several mechanisms involved in metabolic, physiological, and developmental adaptations. In this scenario, microRNAs (miRNAs) have emerged as additional key regulators of nutrients uptake and assimilation. Some studies have demonstrated the intrinsic relation between miRNAs and their targets, and how they can modulate plants to deal with the NPK availability. In this review, we focus on miRNAs and their regulation of targets involved in NPK metabolism. In general, NPK starvation is related with miRNAs that are involved in root-architectural changes and uptake activity modulation. We further show that several miRNAs were discovered to be involved in plant–microbe symbiosis during N and P uptake, and in this way we present a global view of some studies that were conducted in the last years. The integration of current knowledge about miRNA-NPK signaling may help future studies to focus in good candidates genes for the development of important tools for plant nutritional breeding. PMID:26136763

  4. NPK macronutrients and microRNA homeostasis.

    PubMed

    Kulcheski, Franceli R; Côrrea, Régis; Gomes, Igor A; de Lima, Júlio C; Margis, Rogerio

    2015-01-01

    Macronutrients are essential elements for plant growth and development. In natural, non-cultivated systems, the availability of macronutrients is not a limiting factor of growth, due to fast recycling mechanisms. However, their availability might be an issue in modern agricultural practices, since soil has been frequently over exploited. From a crop management perspective, the nitrogen (N), phosphorus (P), and potassium (K) are three important limiting factors and therefore frequently added as fertilizers. NPK are among the nutrients that have been reported to alter post-embryonic root developmental processes and consequently, impairs crop yield. To cope with nutrients scarcity, plants have evolved several mechanisms involved in metabolic, physiological, and developmental adaptations. In this scenario, microRNAs (miRNAs) have emerged as additional key regulators of nutrients uptake and assimilation. Some studies have demonstrated the intrinsic relation between miRNAs and their targets, and how they can modulate plants to deal with the NPK availability. In this review, we focus on miRNAs and their regulation of targets involved in NPK metabolism. In general, NPK starvation is related with miRNAs that are involved in root-architectural changes and uptake activity modulation. We further show that several miRNAs were discovered to be involved in plant-microbe symbiosis during N and P uptake, and in this way we present a global view of some studies that were conducted in the last years. The integration of current knowledge about miRNA-NPK signaling may help future studies to focus in good candidates genes for the development of important tools for plant nutritional breeding. PMID:26136763

  5. Differences in responses of summer and winter spinach to elevated UV-B at varying soil NPK levels.

    PubMed

    Singh, Suruchi; Agrawal, Madhoolika; Agrawal, S B

    2014-05-01

    Seasonal variations in response of spinach to elevated ultraviolet-B (UV-B) during summer and winter were assessed with respect to growth, biomass, yield, NPK uptake and NPK use efficiencies at varying NPK levels. The nutrient amendments were recommended NPK (RNPK) and 1.5 times recommended NPK (1.5 RNPK). Season significantly affected the measured parameters except the number of leaves. Under ambient UV-B, the growth performance of summer spinach was better in both the NPK levels, higher being at 1.5 RNPK leading to higher nutrient uptake. However, more reduction in biomass under elevated UV-B in 1.5 RNPK was recorded during summer, while during winter in RNPK. Reduction in biomass under elevated UV-B was accompanied by the modification in its partitioning with more biomass allocation to root during summer compared to winter at both the NPK levels. NPK uptake was higher in summer, while NPK use efficiencies were higher during winter. At higher than recommended NPK level, better NPK use efficiencies were displayed during both the seasons. Increased NPK supply during winter enabled spinach to capitalize light more efficiently and hence increased biomass accumulation. Strategies for surviving elevated UV-B in winter differ from those that provided protection from the same stress when it occurs in summer. PMID:24474564

  6. N=1=NPK=KIMCHI=N

    E-print Network

    Lee, Jae Rhim, S.M. Massachusetts Institute of Technology

    2006-01-01

    N=1=NPK=KIMCHI=N is a mobile, expandable living unit which consists of a urinal, urine processing system, hydroponic napa cabbage garden, seedling growing area, customized bed, and kitchen table. I tested my urine, modified ...

  7. Evaluation of physiological, growth and yield responses of a tropical oil crop (Brassica campestris L. var. Kranti) under ambient ozone pollution at varying NPK levels.

    PubMed

    Singh, Poonam; Agrawal, Madhoolika; Agrawal, Shashi Bhushan

    2009-03-01

    A field study was conducted to evaluate the impact of ambient ozone on mustard (Brassica campestris L. var. Kranti) plants grown under recommended and 1.5 times recommended NPK doses at a rural site of India using filtered (FCs) and non-filtered open top chambers (NFCs). Ambient mean O(3) concentration varied from 41.65 to 54.2ppb during the experiment. Plants growing in FCs showed higher photosynthetic rate at both NPK levels, but higher stomatal conductance only at recommended NPK. There were improvements in growth parameters and biomass of plants in FCs as compared to NFCs at both NPK levels with higher increments at 1.5 times recommended. Seed yield and harvest index decreased significantly only at recommended NPK in NFCs. Seed quality in terms of nutrients, protein and oil contents reduced in NFCs at recommended NPK. The application of 1.5 times recommended NPK provided protection against yield loss due to ambient O(3). PMID:19070410

  8. Lemon yield and fruit quality affected by NPK fertilization

    Microsoft Academic Search

    J. A Quaggio; D Mattos; H Cantarella; E. L. E Almeida; S. A. B Cardoso

    2002-01-01

    A field trial with Sicilian lemon on Volkameriana rootstock was carried out, during 7 years, in a sandy and low fertility oxisol in the State of São Paulo, Brazil, in order to determine quantitative relationships of lemon yield and fruit quality with NPK fertilization. The experiment was set up in an incomplete factorial design of the (1\\/2) 43 type, summing

  9. CINÉTICA DE ABSORÇÃO DE NUTRIENTES POR ALFACE EM HIDROPONIA - NFT - COM DUAS CONCENTRAÇÕES DA SOLUÇÃO NUTRITIVA

    Microsoft Academic Search

    G. C. S. Matias; N. N. Cometti; M. S. Fernandes

    A absorção de nutrientes pelas plantas pode ser descrita por parâmetros cinéticos: Vmax (máxima velocidade de absorção do nutriente por unidade de raiz), Km (concentração externa na qual a velocidade de absorção é a metade da máxima) e Cmin (concentração externa na qual o fluxo líquido de íons é zero). O uso de parâmetros cinéticos pode auxiliar tanto na seleção

  10. Virtual and Embedded Nutrient Flows from Soybean Production in Mato Grosso, Brazil

    NASA Astrophysics Data System (ADS)

    Lathuilliere, M. J.; Couto, E. G.; Johnson, M. S.

    2012-12-01

    The increase in international trade of agricultural products has enabled consumers to take advantage of distant resources to secure their provision of food. However, such a relationship has also distanced consumers from producers, resulting in environmental footprints often externalized to distant countries. For example, half of all soybeans grown in the state of Mato Grosso, the largest Brazilian soybean producer this past decade, were exported to China and Europe in 2009. This study looks at nitrogen (N), phosphorous (P) and potassium (K) use related to Mato Grosso soybean production and exports to China and Europe in the 2000-2009 period. More specifically we look at 'virtual' and 'embedded' NPK flows to China and Europe, where 'virtual' represents NPK inputs associated with soybean production but not actually embedded in the exported soybeans, and 'embedded' represents the NPK contained within the soybeans. Both virtual and embedded NPK export flows more than doubled between 2000 and 2009, with embedded NPK flows up to 18 times larger than virtual flows on an annual basis. We also quantify nutrient balances resulting from the soybean trade including imported and domestically produced fertilizer. Initial results suggest that the majority of embedded N may cause an issue for importing countries, while virtual P is mostly externalized to Mato Grosso which must rely on limited national production and fertilizer imports to meet P needs. This study contributes towards a more comprehensive understanding of the use of nutrients in soybean production as a component of a more complete environmental impact assessment of this agricultural product.

  11. Growth, yield, and nutrient status of pecans fertilized with biosolids and inoculated with rizosphere fungi

    Microsoft Academic Search

    S. H. Tarango Rivero; V. G. Nevárez Moorillón; E. Orrantia Borunda

    2009-01-01

    The application of anaerobically digested biosolids as a nutrient source for pecan, Carya illinoinensis (Wangeh.) K. Koch, cultivar Western, was evaluated. Conventional NPK fertilizers (CF) and biosolids included a treatment with the rhizospheric fungi Pisolithus tinctorius+Scleroderma sp. and Trichoderma sp. After an average of three years, the tree trunks with biosolid treatment grew 9.5% more than with CF; the length

  12. Chapter 7 Nutrient and Virtual Water Flows in Traded Agricultural Commodities

    Microsoft Academic Search

    Ulrike Grote; Eric T. Craswell; Paul L. G. Vlek

    2008-01-01

    Globalization and increasing population pressure on food demand and land and water resources have stimulated interest in nutrient and virtual water flows at the international level. West Asia\\/North Africa (WANA), Southeast Asia, and sub-Saharan Africa are net importers not only of nitrogen, phosphorus, and potassium (NPK) but also of virtual water in agricultural commodities. Nevertheless, the widely recognized declines in

  13. Impact of long-term N, P, K, and NPK fertilization on the composition and potential functions of the bacterial community in grassland soil.

    PubMed

    Pan, Yao; Cassman, Noriko; de Hollander, Mattias; Mendes, Lucas W; Korevaar, Hein; Geerts, Rob H E M; van Veen, Johannes A; Kuramae, Eiko E

    2014-10-01

    Soil abiotic and biotic interactions govern important ecosystem processes. However, the mechanisms behind these interactions are complex, and the links between specific environmental factors, microbial community structures, and functions are not well understood. Here, we applied DNA shotgun metagenomic techniques to investigate the effect of inorganic fertilizers N, P, K, and NPK on the bacterial community composition and potential functions in grassland soils in a 54-year experiment. Differences in total and available nutrients were found in the treatment soils; interestingly, Al, As, Mg, and Mn contents were variable in N, P, K, and NPK treatments. Bacterial community compositions shifted and Actinobacteria were overrepresented under the four fertilization treatments compared to the control. Redundancy analysis of the soil parameters and the bacterial community profiles showed that Mg, total N, Cd, and Al were linked to community variation. Using correlation analysis, Acidobacteria, Bacteroidetes, and Verrucomicrobia were linked similarly to soil parameters, and Actinobacteria and Proteobacteria were linked separately to different suites of parameters. Surprisingly, we found no fertilizers effect on microbial functional profiles which supports functional redundancy as a mechanism for stabilization of functions during changes in microbial composition. We suggest that functional profiles are more resistant to environmental changes than community compositions in the grassland ecosystem. PMID:25046442

  14. NPK NMR Sensor: Online Monitoring of Nitrogen, Phosphorus, and Potassium in Animal Slurry.

    PubMed

    Sørensen, Morten K; Jensen, Ole; Bakharev, Oleg N; Nyord, Tavs; Nielsen, Niels Chr

    2015-07-01

    Knowledge of the actual content of nitrogen, phosphorus, and potassium (NPK) in animal slurry is highly important to optimize crop production and avoid environmental pollution when slurry is spread on agricultural fields. Here, we present a mobile, low-field nuclear magnetic resonance (NMR) sensor suitable for online monitoring of the NPK content in animal slurry as an alternative to crude estimates or tedious nonspecific, off-site laboratory analysis. The sensor is based on (14)N, (17)O, (31)P, and (39)K NMR in a digital NMR instrument equipped with a 1.5 T Halbach magnet for direct detection of ammonium N, total P, and K and indirect evaluation of the organic N content, covering all practical components of NPK in animal slurry. In correlation studies, the obtained NMR measurements show good agreement with reference measurements from commercial laboratories. PMID:26020811

  15. Nutrient and Virtual Water Flows in Traded Agricultural Commodities

    Microsoft Academic Search

    Ulrike Grote; Eric T. Craswell; Paul L. G. Vlek

    Globalization and increasing population pressure on food demand and land and water resources have stimulated interest in nutrient\\u000a and virtual water flows at the international level. West Asia\\/North Africa (WANA), Southeast Asia, and sub-Saharan Africa\\u000a are net importers not only of nitrogen, phosphorus, and potassium (NPK) but also of virtual water in agricultural commodities.\\u000a Nevertheless, the widely recognized declines in

  16. Longevity of microbial and enzyme activity and their influence on NPK content in pressmud vermicasts

    Microsoft Academic Search

    Kasi Parthasarathi; Lalpet S. Ranganathan

    1999-01-01

    Total microbial population and their activity (CO2 evolution), macronutrients (N, P, K) and enzymes (dehydrogenase and phosphatase activities) in the uningested pressmud, fresh casts and 15- and 30-d-old pressmud vermicasts of two composting worms, Lampito mauritii and Eudrilus eugeniae, have been determined. Enhancement of microbial population and activity, NPK content and enzyme activities in the fresh casts are due to

  17. Biomass production and NPK retention in macrophytes from wetlands of the Tingitan Peninsula

    Microsoft Academic Search

    Abdeslam Ennabili; Mohammed Ater; Michel Radoux

    1998-01-01

    A field study was undertaken on Phragmites australis (Cav.) Trin. Ex Steudel, Typha angustifolia L., Sparganium erectum L., Juncus acutus L., J. maritimus Lam., Scirpus litoralis Schrader, S. maritimus L., Lemna gibba L. and L. minor L. communities, in order to evaluate and compare their biomass production and NPK retention rates in unpolluted and polluted wetlands of northwest Morocco. This

  18. Effects of fertilization on seasonal patterns of foliar mass and nutrients of tamarack and black spruce on undrained

    E-print Network

    Macdonald, Ellen

    Effects of fertilization on seasonal patterns of foliar mass and nutrients of tamarack and black.S.P.) as affected by fertilization of undrained and drained minerotrophic peatland sites. The drained site was ditched in fall 1987. Four N±P±K fertilization treatments, i.e. 0±0±0, 0±80±120, 200±80±120, and 400± 80

  19. Nutrient Depletion

    NSDL National Science Digital Library

    In this activity, students observe nutrient depletion as they germinate and grow nutrient-demanding seedlings. They will discover that all plants require nutrients to grow and thrive and that these nutrients are found in the soil and absorbed through the plants' root systems. They will also learn that nutrients are dissolved in water and are distributed throughout the plant via its circulatory system; when the plants are harvested, they take the nutrients with them, depleting the soil of these essential components.

  20. Chemical reactions during the preparation of P and NPK fertilizers from thermochemically treated sewage sludge ashes

    Microsoft Academic Search

    Christian Vogel; Christian Adam; Burkhard Peplinski; Stephan Wellendorf

    2010-01-01

    In the present paper we show how P and NPK fertilizers can be prepared from thermochemically treated sewage sludge ashes (SSA) and which chemical reactions occur during these post-treatment steps. The SSA used for this investigation was treated thermochemically at a temperature of 1,000°C in a rotary kiln after the addition of calcium chloride hydrate or magnesium chloride hydrate to

  1. The effects of weed-crop competition on nutrient uptake as affected by crop rotation and fertilizers.

    PubMed

    Mohammaddoust-E-Chamanabad, Hamid Reza; Asghari, Ali; Tulikov, Aleksander Mikhailovic

    2007-11-15

    A field study at the Agricultural University of Timiriazev, Moscow, was conducted to determine the effect of crop rotation and Long-term fertilizer application on differences in the competitive ability of spring barley and weeds to nutrient uptake in 2004 and 2005. Spring barley was cultivated in continuous and in crop rotation with winter rye, potato, clover, flax and fallow, with and without NPK application since 1912. Spring barley, especially in no fertilizer plots grown in crop rotation has greater dry mass than spring barley grown in continuous. While dry weed mass markedly decreased in crop rotation. Decrease dry weeds mass was greater when NPK had applied. The statistical analyses show that when spring barley grew in competition with weeds in the no fertilizer plots, crop rotation significantly increased nutrient content in spring barley, but when fertilizer applied the content of N, P2O5 and K2O in barley did not change. Lowest weeds nutrient content observed where soil fertility was increased by crop rotation and NPK application. Crop rotation significantly increased total nutrient uptake of soils by spring barley, but decreased total nutrient uptake by weeds. PMID:19090292

  2. Vegetation feedbacks of nutrient addition lead to a weaker carbon sink in an ombrotrophic bog.

    PubMed

    Larmola, Tuula; Bubier, Jill L; Kobyljanec, Christine; Basiliko, Nathan; Juutinen, Sari; Humphreys, Elyn; Preston, Michael; Moore, Tim R

    2013-12-01

    To study vegetation feedbacks of nutrient addition on carbon sequestration capacity, we investigated vegetation and ecosystem CO2 exchange at Mer Bleue Bog, Canada in plots that had been fertilized with nitrogen (N) or with N plus phosphorus (P) and potassium (K) for 7-12 years. Gross photosynthesis, ecosystem respiration, and net CO2 exchange were measured weekly during May-September 2011 using climate-controlled chambers. A substrate-induced respiration technique was used to determine the functional ability of the microbial community. The highest N and NPK additions were associated with 40% less net CO2 uptake than the control. In the NPK additions, a diminished C sink potential was due to a 20-30% increase in ecosystem respiration, while gross photosynthesis rates did not change as greater vascular plant biomass compensated for the decrease in Sphagnum mosses. In the highest N-only treatment, small reductions in gross photosynthesis and no change in ecosystem respiration led to the reduced C sink. Substrate-induced microbial respiration was significantly higher in all levels of NPK additions compared with control. The temperature sensitivity of respiration in the plots was lower with increasing cumulative N load, suggesting more labile sources of respired CO2 . The weaker C sink potential could be explained by changes in nutrient availability, higher woody : foliar ratio, moss loss, and enhanced decomposition. Stronger responses to NPK fertilization than to N-only fertilization for both shrub biomass production and decomposition suggest that the bog ecosystem is N-P/K colimited rather than N-limited. Negative effects of further N-only deposition were indicated by delayed spring CO2 uptake. In contrast to forests, increased wood formation and surface litter accumulation in bogs seem to reduce the C sink potential owing to the loss of peat-forming Sphagnum. PMID:23868415

  3. Produção de matéria seca e absorção de nutrientes pelo milho em razão da saturação por bases e da adubação potássica

    Microsoft Academic Search

    MARCELO ANDREOTTI; EUCLIDES CAXAMBU ALEXANDRINO DE SOUZA; CARLOS ALEXANDRE COSTA CRUSCIOL; JOÃO DOMINGOS RODRIGUES; LEONARDO THEODORO BÜLL

    2000-01-01

    The purpose of this research was to study dry matter yield and nutrients uptake by corn plants as a function of potassic fertilization and of soil basis saturation. An experiment was conducted under greenhouse conditions, using an early single hybrid corn Zêneca 8392 grown in 30 L pots, tested with three types of soil (Quartzpsamment and two alic Dark-Red Latosol

  4. Effects of soil properties, mulch and NPK fertilizer on maize yields and nutrient budgets on ferralitic soils in southern Benin

    Microsoft Academic Search

    B. H. Janssen; E. J. M. Temminghoff

    2003-01-01

    Four on-farm experiments examined whether modest applications of fertilizers in combination with prunings from native agroforestry trees would be an alternative to maintain the fertility of ferralitic soils in Benin. An application of about 1.9tha?1dry matter of mulch of Senna siamea combined with 30kgNha?1, 22kgPha?1 and 25kgKha?1 as compound fertilizer was compared with (1) 60kgNha?1, 43kgPha?1 and 50kgKha?1 as compound

  5. Differential invasion of a wetland grass explained by tests of nutrients and light availability on establishment and clonal growth

    Microsoft Academic Search

    Deborah A. Maurer; Joy B. Zedler

    2002-01-01

    Phalaris arundinacea (Poaceae) is aggressively invading wetlands across North America. We tested the hypotheses that open canopies and increased nutrients facilitate vegetative establishment in the field, using a phytometer (6 rhizome fragments\\/plot, 24 plots\\/wetland). In each of three wetlands, phytometers received three levels of an NPK fertilizer or served as controls. Emergence and survival differed among sites (P=0.0005), but not

  6. Biomass production and nutrient accumulation in short-rotation grey alder ( Alnus incana (L.) Moench) plantation on abandoned agricultural land

    Microsoft Academic Search

    Veiko Uri; Hardi Tullus; Krista Lõhmus

    2002-01-01

    In 1999, the area of abandoned agricultural land in Estonia formed 223,000ha which is partly perspective for afforestation with grey alder, the most rapidly growing indigenous tree species. The production and nutrient (NPK) accumulation of a grey alder short-rotation plantation on former agricultural land was investigated. The production of above-ground biomass was estimated during 5 years after the establishment of

  7. Nutrient uptake in mycorrhizal symbiosis

    Microsoft Academic Search

    H. Marschner

    1994-01-01

    The role of mycorrhizal fungi in acquisition of mineral nutrients by host plants is examined for three groups of mycorrhizas.\\u000a These are; the ectomycorrhizas (ECM), the ericoid mycorrhizas (EM), and the vesicular-arbuscular mycorrhizas (VAM). Mycorrhizal\\u000a infection may affect the mineral nutrition of the host plant directly by enhancing plant growth through nutrient acquisition\\u000a by the fungus, or indirectly by modifying

  8. Nutrient omission in Bt cotton affects soil organic carbon and nutrients status

    NASA Astrophysics Data System (ADS)

    Aladakatti, Y. R.; Biradar, D. P.; Satyanarayana, T.; Majumdar, K.; Shivamurthy, D.

    2012-04-01

    Studies carried out at the University of Agricultural Sciences, Dharwad, India, in medium black soils assessed the effect of nutrient omission in Bt cotton and its effect on the soil organic carbon (SOC) and available nutrients at the end of second consecutive year of nutrient omission. The study also assessed the extent of contribution of the macro and micronutrients towards seed cotton yield. The experiment consisting 11 treatments omitting a nutrient in each treatment including an absolute control without any nutrients was conducted in a Randomised Block Design with three replications. Cotton crop sufficiently fertilized with macro and micro nutrients (165 : 75 : 120 NPK kg ha-1 and 20 kg each of CaSO4, and MgSO4, 10 kg of S, 20 kg each of ZnSO4, FeSO4 and 0.1 per cent Boron twice as foliar spray) was taken as a standard check to assess the contribution of each nutrient in various nutrient omission treatments. Soils of each treatment were analysed initially and after each crop of cotton for SOC and available nutrient status. Results indicated that the SOC decreased after each crop of cotton in absolute control where no nutrients were applied (0.50 % to 0.38 %) and also in the N omission treatment (0.50 % to 0.35 %). But there was no significant impact of omission of P, K and other nutrients on soil organic carbon. Soil available N, P and K in the soil were reduced as compared to the initial soil status after first and second crop of cotton in the respective treatment where these nutrients were omitted. The soil available N, P and K were reduced to the extent of 61 kg ha-1, 7.1 kg ha-1 and 161.9 kg ha-1 in the respective nutrient omission treatment at end of second crop of cotton as compared to the initial status of these nutrients in the soil. This might be due to the mining of these nutrients from the soil nutrient pool with out addition of these nutrients extraneously. The nutrient status of N, P and K remained almost similar in omission of other nutrients. Omission of N, P and K also reduced the seed cotton yield by 41, 9.3 and 27.3 per cent respectively. Reduction of cotton yield with omission of other nutrients was meager. It is concluded that rate of reduction in SOC, and cotton yield is more pronounced with omission of N than P and K from the regular fertiliser schedule to Bt cotton in medium black soils. However, omission of secondary and micronutrients had least effect on the soil nutrient status and seed cotton yield.

  9. Effects of leguminous plant residues and NPK fertilizer application on the performance of yam (Dioscorea rotundata ‘c.v.’ ewuru) in south-western Nigeria

    Microsoft Academic Search

    Gani Oladejo Kolawole

    2012-01-01

    The effects of cultivating and incorporating residues of previous tropical kudzu (Pueraria phaseoloides) and soybean (Glycine max) with application of NPK fertilizer on yam performance were evaluated at the teaching and research farm, LAUTECH, Nigeria. There were nine treatments: incorporation of legume residues (5 t DM ha), application of recommended fertilizer rate for yam (90–50–75 kg NPK ha) in the zone or

  10. Nutrient Management

    NSDL National Science Digital Library

    This Iowa Department of Natural Resources PowerPoint presentation educates the public about sources of excess nutrients in the Mississippi River and outlines preventative steps to stop the influx. It is directed toward Iowa citizens, but may be applied to other states as well. This presentation features color photographs and diagrams.

  11. NUTRIENT MANAGEMENT Revised June 2006

    E-print Network

    Tullos, Desiree

    or dried rather than sent moist at room temperature. · Beware of low prices. Laboratory procedures cost for drinking water analysis can be obtained by contact- ing the Oregon Health Division, Drinking Water SystemsNUTRIENT MANAGEMENT EM 8677 Revised June 2006 Laboratories Serving Oregon Soil, Water, Plant Tissue

  12. NUTRIENT MANAGEMENT Revised May 2008

    E-print Network

    Tullos, Desiree

    or dried rather than sent moist at room temperature. · Beware of low prices. Laboratory procedures cost for drinking water analysis, contact the Oregon Health Division, Drinking Water Systems, P.O. Box 14450NUTRIENT MANAGEMENT EM 8677 Revised May 2008 Laboratories Serving Oregon Soil, Water, Plant Tissue

  13. Enhancement of growth and nutrient uptake of rapeseed (Brassica napus L.) by applying mineral nutrients and biofertilizers.

    PubMed

    Yasari, Esmaeil; Azadgoleh, M A Esmaeili; Mozafari, Saedeh; Alashti, Mahsa Rafati

    2009-01-15

    For investigating the effect of chemical fertilizer as well as biofertilizers on seed yield and quality i.e. oil, protein and nutrients concentration of rapeseed (Brassica napus L.), a split-plot fertilizers application experimental design in 4 replications was carried out during the 2005-2006 growing season, at the Gharakheil Agricultural Research Station in the Mazandaran province of Iran. Rapeseed was grown as a second crop in rotation after rice. Biofertilizers treatments were two different levels: control (no seed inoculation) and seeds inoculation with a combination of Azotobacter chroococcum and Azosprillum brasilense and Azosprillum lipoferum, as main plot and chemical fertilizers comprised N, P, K and their combinations, NPKS and NPK Zn as sub plots. The maximum value of seed yield obtained at (BF+NPK Zn) 3421.2 kg h(-1) corresponding to 244.5 pods per plant and maximum concentration of Zn in leaves as well as seeds. The highest weight of 1000 seeds (4.45 g) happened to obtain at (BF+NPK S) which coinciding with the maximum K levels in leaves. The highest number of branches was obtained at (BF+NPK Zn) with 4.43 branches per plant i.e., 46.2% increase over the control. The maximum value of rapeseed oil content 47.73% obtained at T16 (BF+NK) but maximum protein concentration of seed obtained at T12 (BF+N). Overall the results indicated that inoculation resulted in increase in seeds yield (21.17%), number of pods per plant (16.05%), number of branches (11.78%), weight of 1000 grain (2.92%), oil content of seeds (1.73%) and protein (3.91%) but decrease (-0.24%) in number of seeds per pods comparing to non-Biofertilizers treatments. Irrespective to the treatments, results showed that application of Biofertilizers coincided with 3.86, 0.82, 2.25, 0.75 and 0.91% increase in concentrations of N, P, K, S and Zn in the seeds over the non-Biofertilizers treatments. PMID:19579932

  14. The combination of NPK fertilizer and deltamethrin insecticide favors the proliferation of pyrethroid-resistant Anopheles gambiae (Diptera: Culicidae)

    PubMed Central

    Darriet, F.; Rossignol, M.; Chandre, F.

    2012-01-01

    In this laboratory study, we investigated how the biological cycle of Anopheles gambiae s.s. (VKPR strain) would be like when grew in an environment containing more or less plant matter (2.5 or 5 g/l) and fertilizer (8-12-8 or 17-23-17 mg/l). Half of the environments studied were not exposed to insecticide (control) whereas the other half was submitted to deltamethrin treatment at the concentration of 0.015 mg/l. The bioassays showed that 2.5 g/l of plant matter in water are not sufficient to feed the hundred larvae, each breeding site contains. Treating these breeding sites with deltamethrin reversed the situation as it decreased the competition for food resources and allowed the surviving larvae to share the small amount of food enabling them to pursue their development until adults. If the introduction of NPK in untreated sites has not improved the nutritive qualities of the water, in the treated sites it multiplied the number of emerging adults by 2.5. In the waters containing 5 g/l of plant matter, the larvae did not undergo feeding competition and the impact of insecticide followed of a more traditional selection scheme that expressed itself by a lower number of emerging adults. In these environments treated or nontreated where plant matter is abundant, adding NPK brings food supplement to the larvae therefore increases the survival rate of An. gambiae. To conclude, whether in habitats with little or much plant matter, NPK presence in water results in larger adults with generally, more soluble proteins. PMID:22550627

  15. Preparation and properties of a double-coated slow-release NPK compound fertilizer with superabsorbent and water-retention.

    PubMed

    Wu, Lan; Liu, Mingzhu; Rui Liang

    2008-02-01

    A double-coated slow-release NPK compound fertilizer with superabsorbent and water-retention was prepared by crosslinked poly(acrylic acid)/diatomite - containing urea (the outer coating), chitosan (the inner coating), and water-soluble granular fertilizer NPK (the core). The effects of the amount of crosslinker, initiator, degree of neutralization of acrylic acid, initial monomer and diatomite concentration on water absorbency were investigated and optimized. The water absorbency of the product was 75 times its own weight if it was allowed to swell in tap water at room temperature for 2 h. Atomic absorption spectrophotometer and element analysis results showed that the product contained 8.47% potassium (shown by K(2)O), 8.51% phosphorus (shown by P(2)O(5)), and 15.77% nitrogen. We also investigated the water-retention property of the product and the slow release behavior of N, P and K in the product. This product with excellent slow release and water-retention capacity, being nontoxic in soil and environment-friendly, could be especially useful in agricultural and horticultural applications. PMID:17320380

  16. [Effect of NPK and B supply levels on boron uptake and biological properties of different genotypic oilseed rape].

    PubMed

    Lou, Y; Yang, Y

    2001-04-01

    Pot experiment was conducted to study the boron absorption by oilseed rape(Brassica napus), the mechanism of its resistance to boron deficiency, and the effect of boron deficiency on its biological properties under different NPK supply levels. The results indicated that under boron deficiency, increasing NPK supply aggravated boron deficiency symptoms, which led to the decrease of leaf area and its growth rate and nitrate reductase activity(NRA) and the increase of chlorophyll(a + b) content at seedling stage, and the decrease of the number of productive branches and pods of each plant and seed yield at maturity. It was suggested that the ratio of boron concentration in youngest open leaves(YOL) to youngest mature leaves(YML) at seedling stage could be an index to judge the boron mobility in plants of different genotypic oilseed rape. Boron mobility and its utilization efficiency were one of the important nutritional mechanisms responsible for the difference in response of different genotypic oilseed rapes to boron deficiency. PMID:11757364

  17. Chemical evaluation of nutrient supply from fly ash-biosolids mixtures

    SciTech Connect

    Schumann, A.W.; Sumner, M.E.

    2000-02-01

    Prediction of plant nutrient supply from fly ash and biosolids (sewage sludge and poultry manure) may enhance their agricultural use as crop fertilizer. Two mild extraction methods (42-d equilibration with ion-exchange resins; 2-d equilibration with pH 4.8 buffered nutrient solution) and analysis of nutrient data by the Diagnosis and Recommendation Integrated System (DRIS) were tested with 29 fly ash samples, four biosolids samples, and their mixtures. The resin method was useful for major nutrient (N, P, K, Ca, Mg, S) extraction from fly ashes and organic materials, particularly where mineralizable fractions of N and P under aerobic conditions are required. However, resins were inefficient in extracting P from high-Fe sewage sludges because organic waste samples caused premature failure of semipermeable membranes and fouling of resins. Extraction of fly ash with dilute buffered nutrient solution was more successful because micronutrient recovery was improved, major nutrients were correlated to the resin method, both addition and removal of nutrients were recorded. DRIS analysis was possible, and equilibration was rapid (2 d). The overall nutrient supply from these extremely variable fly ashes was: Cu = Fe {approx} B {approx} Mo > Ca > S > Zn >> Mn > N > Mg > P > K (high micronutrient, low major nutrient supply). For biosolids, the major nutrients ranked: P > N {approx} Ca > S > Mg > K (sewage sludges), and N > Ca {approx} K > P > Mg > S (poultry manures). In mixtures of fly ash with 26% sewage sludge the order was: Ca > S > N > Mg > P > K, while in mixtures of fly ash and 13% poultry manure, the nutrients ranked: Ca > K {approx} N {approx} S > Mg > P. Optimal plant nutrition (especially N-P-K balancing) should be possible by mixing these three waste materials.

  18. Nutrient absorption.

    PubMed

    Siddiqi, S A; Kumar, N S; St Hilaire, R J; Nutting, D F; Mansbach, C M

    2000-03-01

    Some key advances occurred last year in understanding mechanisms involved in nutrient absorption. A novel "prechylomicron transport vesicle" was identified; its movement to the Golgi is the rate-limiting step for triacylglycerol absorption. A scavenger receptor (type BI) in the brush border membrane appears to facilitate cholesterol uptake. Several studies define mechanisms for gastrointestinal peptide hormone stimulation of glucose uptake. An oligopeptide transporter, PepT1, is transcriptionally upregulated by certain dietary amino acids and dipeptides. Surprisingly, both insulin and fasting double the maximum velocity for dipeptide uptake (via PepT1), but they act by different mechanisms. Three transporters, SMVT (sodium-dependent multivitamin transporter for biotin and pantothenate), SVCT (for vitamin C), and CaT1 (for Ca uptake from the lumen) have been cloned and are active when expressed in various cells. Additional studies provide insights on Ca absorption and vitamin D action in aging, estrogen deficiency, and adaptation to a low Ca diet. Nramp2, also called DMT1 (divalent metal ion transporter), seems to be a major regulator of transferrin-independent, nonheme iron uptake. Finally, the protein HFE associates with the transferrin receptor and is part of an iron-sensing mechanism that regulates iron absorption. It is defective in hereditary hemochromatosis. HFE and Nramp2 (DMT1) genes are reciprocally regulated. PMID:17024033

  19. Effect of Sowing Methods and NPK Levels on Growth and Yield of Rainfed Maize (Zea mays L.)

    PubMed Central

    2015-01-01

    To investigate the response of rainfed maize to sowing methods and NPK levels, an experiment was undertaken during kharif of 2011 and 2012 at Dryland (Kerawa) Agriculture Research Station, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Budgam. The experiment was laid out in a randomized block design with combination of 2 sowing methods (flat sowing, 75?cm apart rows, and ridge sowing, 75?cm apart ridges) and 3 fertility levels (60?:?40?:?20, 75?:?50?:?30, and 90?:?60?:?40 N?:?P2O5?:?K2O?kg?ha?1) with three replications. Various growth characters, namely, plant height, leaf area index, dry matter accumulation, number of days to different phenological stages, and yield, and yield contributing characters namely, cob length, number of grains cob?1, cob diameter (cm), and 100-seed weight (g), were significantly higher with S2 over S1 during both the years of experimentation. Fertilizer levels F3 (90?:?60?:?40) and F2 (75?:?50?:?30) at par with one another produced significant increase in growth and yield characters, namely, plant height, leaf area index, dry matter production at different growth stages, cob length, number of cobs plant?1, number of grains cob?1, and 100-seed weight over F1 (60?:?40?:?20). Significantly higher grain yield was recorded with fertilizer level F3 (90?:?60?:?40) being at par with F2 (75?:?50?:?30) and showed significant increase over F1 (60?:?40?:?20) with superiority of 5.4 and 5.7 per cent during 2011 and 2012, respectively. The findings of the study concluded that ridge method of sowing of maize with NPK levels of 75?:?50?:?30?kg?ha?1 showed better performance of crop in terms of growth, yield, and yield attributes.

  20. Effect of Effective Microorganism Application on Crop Growth, Yield, and Nutrition in Vigna radiata (L.) Wilczek in Different Soil Amendment Systems

    Microsoft Academic Search

    Arshad Javaid; Rukhsana Bajwa

    2011-01-01

    A pot experiment was conducted in heat-sterilized soil to evaluate the effect of effective microorganism (EM) application on growth, yield, and nutrient uptake in Vigna radiata (L.) Wilczek var. NIAB Mung 98 in different soil amendment systems. Pot soil was amended with farmyard manure (FYM), Trifolium alexanrinum L. crop residues (TCR), and half (½NPK) and recommended dose (NPK) of chemical

  1. NATIONAL NUTRIENTS DATABASE

    EPA Science Inventory

    Resource Purpose: The Nutrient Criteria Program has initiated development of a National relational database application that will be used to store and analyze nutrient data. The ultimate use of these data will be to derive ecoregion- and waterbody-specific numeric nutrient...

  2. Effect of Crop Residue With and Without a Culture of Cellulolytic Fungi on Yield, NPK Uptake and Soil Fertility Under Rice-Wheat Cropping System

    Microsoft Academic Search

    S. N. Sharma; R. Prasad

    2002-01-01

    The field experiments were carried out at Indian Agricultural Research Institute, New Delhi during three crop cycles from 1996-97 to 1998-99 to study the effect of incorporation of wheat and rice residues with and without a culture of cellulolytic fungi Trichrus spiralis on grain and straw yields and NPK uptake of rice-wheat cropping system and organic C, available P and

  3. Some effects of a soluble NPK fertilizer on sensitivity of eastern white pine to injury from SOâ air pollution. [Pinus strobus

    Microsoft Academic Search

    C. Cotrufo; C. R. Berry

    1970-01-01

    SOâ-sensitive and -tolerant clones of eastern white pine (Pinus strobus L.) were fertilized with a soluble NPK formulation (23:19:17) and artificially exposed to SOâ when the needles were 25 to 50 mm long. Similarly fertilized potted clones were exposed to ambient air in a field where SOâ is believed to be a major pollutant. The fertilizer applications reduced the extent

  4. Movement of pesticides and nutrients into tile drainage water. Final report, 22 September 1985-22 September 1988

    SciTech Connect

    Van Scoyoc, G.E.; Kladivko, E.J.

    1989-01-01

    Concern about contamination of surface and ground water by agricultural chemicals has increased in the last five years. The objectives of this study were to determine field-scale pesticide and nutrient losses to tile drains over a 3-year period on a low-organic-matter, poorly structured silt loam soil under typical agricultural management practices. A tile-drainage spacing study was instrumented to measure water outflow rates and to continuously collect tile outflow samples on a flow-proportional basis. Two replicates of 3 tile spacings (5, 10, and 20 m) were included in the study. Water samples were analyzed for all applied pesticides (atrazine, cyanazine, alachlor, carbofuran, terbufos, and chlorpyrifos) as well as major nutrients (N,P,K) and sediment.

  5. Plant biomass and nutrient flux in a managed mangrove forest in Malaysia

    NASA Astrophysics Data System (ADS)

    Gong, Wooi-Khoon; Ong, Jin-Eong

    1990-11-01

    This paper summarizes previously reported and new data. Data on biomass and nutrient content in different components of the mangrove trees are presented and estimates of the flux of these are attempted. As a first step to determining the quantitative relationship between the export of material and the areal extent of mangroves, the biomass and nutrients contained in the mangrove trees and the release of these to the ecosystem annually were determined for the 40 800-ha Matang Mangrove Forest Reserve—a managed mangrove forest in Malaysia. The total standing biomass of the Matang Mangrove Forest is estimated to be 8·26 milion tonnes (of dry matter). Biomass released annually from the mangrove trees in the Matang system is 1 015 980 tonnes. Of these, 559 500 tonnes or 55% is in the form of dead trees, 396 840 tonnes (39%) is in the form of small litter and 59 640 (6%) in the slash left behind after thinning and harvesting. The amounts of macro-nutrients (N,P,K, Ca, Mg and Na) released annually are 12 210, 11 870 and 2690 tonnes through litter, dead trees and slash respectively. The fate of these materials is discussed. Using the figure of 50% export, the export of biomass and nutrients from the Matang Mangroves through leaf litter alone is estimated as 158 300 and 5100 tonnes annually or 3·9 and 0·1 tonne ha -1 year -1 respectively.

  6. Growth, yield, and nutrient status of pecans fertilized with biosolids and inoculated with rizosphere fungi.

    PubMed

    Tarango Rivero, S H; Nevárez Moorillón, V G; Orrantia Borunda, E

    2009-03-01

    The application of anaerobically digested biosolids as a nutrient source for pecan, Carya illinoinensis (Wangeh.) K. Koch, cultivar Western, was evaluated. Conventional NPK fertilizers (CF) and biosolids included a treatment with the rhizospheric fungi Pisolithus tinctorius+Scleroderma sp. and Trichoderma sp. After an average of three years, the tree trunks with biosolid treatment grew 9.5% more than with CF; the length of the bearing shoots was 18.1 and 18.3cm and the production of nuts/tree was 9.26 and 8.75kg for pecans with CF and with biosolids, respectively. Western foliar nutrient concentration and nut quality were statistically equal in trees with CF and with biosolids. Soil inoculation with mycorrhizal fungi improved shoot growth by 19.4% when CF was applied, but did not when biosolids were used. Nutrient status and yield did not increase with mycorrhizal fungi. The addition of Trichoderma sp. did not favor any of the variables evaluated with both nutrient sources. Biosolids are efficient fertilizer at promoting the growth, production and nut quality of pecan trees. PMID:18993060

  7. Estimating nutrient surplus and nutrient use efficiency from farm characteristics

    Microsoft Academic Search

    J. W. A. Langeveld; G. B. Overbosch

    1995-01-01

    Research on nutrient losses from agricultural systems should try to relate these losses to farm characteristics. This was done for private farms in two districts in Poland. Using data from a farm survey, nutrient surpluses and Nutrient Use Efficiency (NUE, defined as the ratio of outgoing and incoming nutrients) were calculated for nitrogen and phosphorus. Both nutrient surplus and NUE

  8. NUTRIENT INTERACTIONS IN CROP PLANTS

    Microsoft Academic Search

    V. D. Fageria

    2001-01-01

    Balanced supply of of essential nutrients is one of the most important factors in increasing crop yields. The objective of this review is to discuss interactions among major and minor nutrients in crop plants. In crop plants, the nutrient interactions are generaly measured in terms of growth response and change in concentration of nutrients. Upon addition of two nutrients, a

  9. Digestate as nutrient source for biomass production of sida, lucerne and maize

    NASA Astrophysics Data System (ADS)

    Bueno Piaz Barbosa, Daniela; Nabel, Moritz; Horsch, David; Tsay, Gabriela; Jablonowski, Nicolai

    2014-05-01

    Biogas as a renewable energy source is supported in many countries driven by climate and energy policies. Nowadays, Germany is the largest biogas producer in the European Union. A sustainable resource management has to be considered within this growing scenario of biogas production systems and its environmental impacts. In this respect, studies aiming to enhance the management of biogas residues, which represents a valuable source of nutrients and organic fertilization, are needed. Our objective was to evaluate the digestate (biogas residue after fermentation process) application as nutrient source for biomass production of three different plants: sida (Sida hermaphrodita - Malvaceae), lucerne (Medicago sativa - Fabaceae) and maize (Zea mays - Poaceae). The digestate was collected from an operating biogas facility (fermenter volume 2500m³, ADRW Natur Power GmbH & Co.KG Titz/Ameln, Germany) composed of maize silage as the major feedstock, and minor amounts of chicken manure, with a composition of 3,29% N; 1,07% P; 3,42% K; and 41,2% C. An arable field soil (Endogleyic Stagnosol) was collected from 0-30 cm depth and 5 mm sieved. The fertilizer treatments of the plants were established in five replicates including digestate (application amount equivalent to 40 t ha-1) and NPK fertilizer (application amount equivalent to 200:100:300 kg ha-1) applications, according to the recommended agricultural doses, and a control (no fertilizer application). The digestate and the NPK fertilizer were thoroughly mixed with the soil in a rotatory shaker for 30 min. The 1L pots were filled with the fertilized soil and the seedlings were transplanted and grown for 30 days under greenhouse conditions (16 h day/8 h night: 24ºC/18ºC; 60% air humidity). After harvesting, the leaf area was immediately measured, and the roots were washed to allow above and below-ground biomass determination. Subsequently, shoots and roots were dried at 60ºC for 48 hours. The biomass and leaf area of sida, lucerne and maize presented similar performance for both digestate and the NPK fertilizer applications, which were greater than the control, showing a positive fertilizing effect of the digestate for plant biomass production. Considering the biomass production obtained with the digestate application for sida, lucerne and maize, the results give support for further field experiments which aim to evaluate the fertilizing and conditioning effect of digestates.

  10. The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions

    E-print Network

    Bequette, Brian J.

    The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions intermediates were analyzed by GC-MS followed by 13 C-mass isotopomer distribution analysis. Glucose metabolism

  11. Food Groups and Nutrients

    NSDL National Science Digital Library

    Miss Perry

    2007-11-08

    State core objective: 3rd grade Health Standard 6 Objective 2. Students will learn the basic nutrient groups and be able to identify the functions of those nutrients. There is an interactive food pyramid for you to explore and several games that will help you learn how each nutrient is used in our bodies! Learning about nutrition is fun and useful! When you have learned all about the nutrient groups you will create your own food pyramid with your favorite foods and how they help your body. There are five basic food groups: Grains, vegetables, fruits, meat, and dairy. These groups are organized into a pyramid, showing about how much of each you should eat each day. There is also a small section for sugars and fats. This pyramid will let you explore what ...

  12. Program Areas Nutrient Management

    E-print Network

    Program Areas Nutrient Management Animal Waste Management Irrigation Water Management Drinking on streamside vegetation and stormwater management (www.caes.uga.edu/extension/water Water and Rural Urban Interface Education Water Policy and Economics Watershed Education

  13. Using a Segmented Model to Describe In situ Nutrient Disappearance

    Microsoft Academic Search

    Stacey A. Gunter; Michael L. Galyean

    2000-01-01

    Gunter, S.A. and Galyean, M.L. 2000. Using a segmented model to describe in situ nutrient disappearance. J. Appl. Anim. Res., 18: 1–14.The purpose of this study was to compare the predictive results and characteristics of exponential (EM) and segmented, models (SM) describing ruminal in situ nutrient disappearance data. Using masticate samples collected from esophageally cannulated steers grazing midgrass prairie rangeland

  14. Ocean Currents: Sinking Nutrients

    NSDL National Science Digital Library

    This two-minute sound segment discusses the nutrients produced by phytoplankton, one-celled plants which live on the surface of the ocean and which form the basis of what scientists call biological productivity. A professor explains that the organic matter that comes sinking out of the surface actually sinks very far down into the water column before bacteria are actually able to break it back down into dissolved nutrients and it is difficult for the water that those nutrients are in to come back up to the surface. This site is from an archive of a daily radio program called Pulse of the Planet, which provides its listeners with a portrait of Planet Earth, tracking the rhythms of nature, culture and science worldwide and blending interviews and extraordinary natural sound. The site also provides a written transcript of the broadcast.

  15. Estimation of stream nutrient uptake from nutrient addition experiments

    SciTech Connect

    Payn, Robert [Virginia Polytechnic Institute and State University (Virginia Tech)

    2005-09-01

    Nutrient uptake in streams is often quantified by determining nutrient uptake length. However, current methods for measuring nutrient uptake length are often impractical, expensive, or demonstrably incorrect. We have developed a new method to estimate ambient nutrient uptake lengths using field experiments involving several levels of nutrient addition. Data analysis involves plotting nutrient addition uptake lengths versus added concentration and extrapolating to the negative ambient concentration. This method is relatively easy, inexpensive, and based on sound theoretical development. It is more accurate than the commonly used method involving a single nutrient addition. The utility of the method is supported by field studies directly comparing our new method with isotopic tracer methods for determining uptake lengths of phosphorus, ammonium, and nitrate. Our method also provides parameters for comparing potential nutrient limitation among streams.

  16. Assessment of the interactive effects of ambient O? and NPK levels on two tropical mustard varieties (Brassica campestris L.) using open-top chambers.

    PubMed

    Singh, Poonam; Singh, Shalini; Agrawal, S B; Agrawal, Madhoolika

    2012-10-01

    Rising O(3) concentrations in agricultural areas have been identified as a significant threat to crop production in Asia including India. The present work reports the results of a field study conducted to assess the usefulness of higher than recommended NPK dose in modifying the physiological, growth, yield, and seed quality responses of two mustard (Brassica campestris L. var. Vardan and Aashirwad) varieties under ambient ozone level at a rural site of India, using open-top chambers. Twelve hourly mean O(3) concentrations ranged between 27.7 and 59.04 ppb during the growth period. Plants in nonfiltered chambers (NFCs) showed reductions in photosynthetic rate, stomatal conductance, and growth parameters compared to the plants in filtered chambers (FCs), but reductions were of lower magnitude at 1.5 times recommended dose of NPK (1.5 RNPK) compared to recommended (RNPK). Yield and seed quality reduced significantly in plants of NFCs compared to FCs at RNPK, but no significant differences were recorded at 1.5 RNPK. There were higher N uptake and N uptake efficiency of plants in FCs compared to NFCs. Nitrogen utilization efficiency increased in Vardan, but decreased in Aashirwad in NFCs compared to FCs suggesting higher capability of N acquisition and utilization under ambient O(3), which led to a less pronounced reduction in the yield of the former than the latter variety. The differential nitrogen utilization efficiency in these varieties may be potentially used as measure of sensitivity characteristics in breeding programs for yield improvement in mustard under the present trend of increase in O(3) concentrations. PMID:22072445

  17. Urban nUtrient Urban nUtrient

    E-print Network

    Liskiewicz, Maciej

    Urban nUtrient ManageMent Handbook #12;#12;Urban nUtrient ManageMent Handbook Content Coordinators of the Virginia Department of Conservation and Recreation. May 2011 #12;#12;Urban Nutrient Management Handbook I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 Chapter 3. Managing Urban Soils What Is an Urban Soil

  18. Nutrient Profile of Hypothermics

    Microsoft Academic Search

    E. R. Braverman; B. Ivovich

    Three abnormal, young female hypotherms with mental retardation had basal temperatures of 88 degrees. Endocrinological evaluations were all negative. An evaluation of nutritional factors was undertaken. No significant changes were found in serum zinc, copper, iron and histamine. Twenty-three nutrients measured in hair showed significant elevations in strontium and sulfur. Analysis of plasma amino acids showed decreases in leucine, isoleucine,

  19. Ocean nutrient enhancer \\

    Microsoft Academic Search

    Satoshi Masuda; Masayuki Yonezawa; Masao Morikawa

    2004-01-01

    The ocean nutrient enhancer (ONE) is composed of a spar type floating structure from which is suspended a 175 m long compliant steel riser. The ONE was installed at the center of Sagami-Bay in May 2003 for the purpose of discharging density controlled water, which is adjusted by mixing the up-welled deep ocean water (DOW) and surface water, into the

  20. Nutrition: What are Nutrients?

    NSDL National Science Digital Library

    2010-05-24

    Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach This Science Object is the third of four Science Objects in the Nutrition SciPack. It explores nutrients and

  1. Nutrient Requirements in Adolescence.

    ERIC Educational Resources Information Center

    McKigney, John I,; Munro, Hamish N.

    It is important to understand the nutrient requirements and the significance of nutrition both in pubescence and adolescence. The pubescent growth spurt is characterized by an increase in body size and a change in proportion of different tissues. Both of these factors are of great nutritional importance, since there is reason to believe that the…

  2. Nutrient Criteria Research

    EPA Science Inventory

    EPA has developed methodologies for deriving nutrient criteria, default criteria for the variety of waters and eco-regions found in the U.S., and a strategy for implementing the criteria including guidance on the use and development of biocriteria. Whereas preliminary research ha...

  3. AGRICULTURAL -NUTRIENT PATiIWAYS

    E-print Network

    Slough Watershed. Minimum November Levels. 18 Figure 4 Nitrate for the Clayburn Creek - Matsqui Slough Watershed. Autumn Levels. 19 Figure 5 Nutrient Pathways. 20 LIST OF TABLES Table 1 Nutrients Excreted

  4. CSREES Nutrient Management Working Meeting

    E-print Network

    or "themes": · Animal Waste Management · Drinking Water and Human Health · Environmental Restoration · Nutrient and Pesticide Management · Pollution Prevention · Watershed Management · Water Quantity and PolicyWelcome CSREES Nutrient Management Working Meeting May 4 and 5, 2004 Atlanta, GA #12;University

  5. Use of plant residues for improving soil fertility, pod nutrients, root growth and pod weight of okra (Abelmoschus esculentum L).

    PubMed

    Moyin-Jesu, Emmanuel Ibukunoluwa

    2007-08-01

    The effect of wood ash, sawdust, ground cocoa husk, spent grain and rice bran upon root development, ash content, pod yield and nutrient status and soil fertility for okra (Abelmoschus esculentum L NHAe 47 variety) was studied. The five organic fertilizer treatments were compared to chemical fertilizer (400kg/ha/crop NPK 15-15-15) and unfertilized controls in four field experiments replicated four times in a randomized complete block design. The results showed that the application of 6tha(-1) of plant residues increased (P<0.05) the soil N, P, K, Ca, Mg, pH, and SOM; pod N, P, K, Ca, Mg and ash; root length; and pod yield of okra in all four experiments relative to the control treatment. For instance, spent grain treatment increased the okra pod yield by 99%, 33%, 50%, 49%, 65% and 67% compared to control, NPK, wood ash, cocoa husk, rice bran and sawdust treatments respectively. In the stepwise regression, out of the total R(2) value of 0.83 for the soil nutrients to the pod yield of okra; soil N accounted for 50% of the soil fertility improvement and yield of okra. Spent grain, wood ash and cocoa husk were the most effective in improving okra pod weight, pod nutrients, ash content, root length and soil fertility whereas the rice bran and sawdust were the least effective. This was because the spent grain, wood ash and cocoa husk had lower C/N ratio and higher nutrient composition than rice bran and sawdust, thus, the former enhanced an increase in pod nutrients, composition for better human dietary intake, increased the root length, pod weight of okra and improved soil fertility and plant nutrition crop. The significance of the increases in okra mineral nutrition concentration by plant residues is that consumers will consume more of these minerals in their meals and monetarily spend less for purchasing vitamins and mineral supplement drugs to meet health requirements. In addition, the increase in plant nutrition and soil fertility would help to reduce the high cost of buying synthetic inorganic fertilizers and maintain the long term productivity of soils for sustainable cultivation of okra. PMID:17336057

  6. Agronomy Facts 40 Nutrient Management

    E-print Network

    Kaye, Jason P.

    operations were required to develop and implement approved nutrient management plans. Also, many other animal requirements on high- density animal operations. This fact sheet summarizes the nutrient management provisionsAgronomy Facts 40 Nutrient Management Legislation in Pennsylvania: A Summary of the 2006

  7. Nutrient profiling: the new environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2005 Dietary Guidelines for Americans (DGA) recommends that individuals choose nutrient-dense foods to help meet nutrient needs without consuming excess calories, a concept that is supported by health professionals and nutrition organizations. With an increased emphasis on nutrient density, the ...

  8. Urban nutrient balance for Bangkok

    Microsoft Academic Search

    Jens Færge; Jakob Magid

    2001-01-01

    To explore the options for recycling of nutrients from mega-cities to agricultural land, a nutrient balance model was developed. The balancing was done for Bangkok Province and considered nitrogen (N) and phosphorus (P). To estimate the food supply, the most decisive nutrient flow, an online database (faostat) was employed; its country level data are disaggregated to the urban level. A

  9. Estuarine macrofauna responses to continuous in situ nutrient addition on a tropical mudflat.

    PubMed

    Botter-Carvalho, Mônica L; Carvalho, Paulo V V C; Valença, Ana Paula M C; Santos, Paulo J P

    2014-06-15

    A field experiment to assess the effects of continuous nutrient addition on the macrobenthic community was carried out on an estuarine mudflat on the northeast coast of Brazil. The experiment began on 5 October 2005 and ended on 8 February 2006. Macrofauna was compared at approximately four-week intervals in triplicate plots with three levels (Control - C, Low Dose - LD and High Dose - HD) of weekly fertilizer additions for 17 weeks. Inorganic fertilizer (N-P-K) was applied on nine randomly defined quadrangular plots (4m(2) each). All measurements were calculated from species abundances. Multivariate analyses as well as the univariate indices (richness, abundance and Shannon-Wiener index) showed statistically significant differences between the enriched and control areas during the period of the experiment. The expected gradual response based on the succession model of Pearson and Rosenberg was not observed. The nutrient doses used were high enough to cause severe decreases in abundance, richness and evenness, and an increase in dominance. PMID:24835372

  10. The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions

    E-print Network

    Hammock, Bruce D.

    -Agricultural Research Service Western Human Nutrition Research Center, 5 Nutrition Department, and 6 DepartmentThe Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions of Entomology, University of California, Davis, CA; 7 Food Science and Nutrition Department, California

  11. The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interaction

    E-print Network

    Paris-Sud XI, Université de

    The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interaction Dietary Salen,3 Franc¸ois Laporte,4 Chiara Tonelli,5 and Michel de Lorgeril3 * 3 Laboratoire Coeur et Nutrition with constant intakes of plant and marine (n-3) PUFA for 8 wk (Expt. 1). Plasma fatty acids were measured by GC

  12. Identification of climate-resilient integrated nutrient management practices for rice-rice cropping system--an empirical approach to uphold food security.

    PubMed

    Subash, N; Gangwar, B; Singh, Rajbir; Sikka, A K

    2015-01-01

    Yield datasets of long-term experiments on integrated nutrient management in rice-rice cropping systems were used to investigate the relationship of variability in rainfall, temperature, and integrated nutrient management (INM) practices in rice-rice cropping system in three different agroecological regions of India. Twelve treatments with different combinations of inorganic (chemical fertilizer) and organic (farmyard manure, green manure, and paddy straw) were compared with farmer's conventional practice. The intraseasonal variations in rice yields are largely driven by rainfall during kharif rice and by temperature during rabi rice. Half of the standard deviation from the average monthly as well as seasonal rainfall during kharif rice and 1 °C increase or decrease from the average maximum and minimum temperature during rabi rice has been taken as the classification of yield groups. The trends in the date of effective onset of monsoon indicate a 36-day delay during the 30-year period at Rajendranagar, which is statistically significant at 95 % confidence level. The mean annual maximum temperature shows an increasing trend in all the study sites. The length of monsoon also showed a shrinking trend in the rate of 40 days during the 30-year study period at Rajendranagar representing a semiarid region. At Bhubaneshwar, the application of 50 % recommended NPK through chemical fertilizers and 50 % N through green manure resulted in an overall average higher increase of 5.1 % in system productivity under both excess and deficit rainfall years and also during the years having seasonal mean maximum temperature ?35 °C. However, at Jorhat, the application of 50 % recommended NPK through chemical fertilizers and 50 % N through straw resulted in an overall average higher increase of 7.4 % in system productivity, while at Rajendranagar, the application of 75 % NPK through chemical fertilizers and 25 % N through green manusre resulted in an overall average higher increase of 8.8 % in system productivity. This study highlights the adaptive capacity of different integrated nutrient management practices to rainfall and temperature variability under a rice-rice cropping system in humid, subhumid, and semiarid ecosystems. PMID:24817490

  13. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice*

    PubMed Central

    Zhang, Qi-chun; Wang, Guang-huo

    2005-01-01

    The ecosystem characteristics of soil microorganism and the nutrient uptake of irrigated rice were investigated in a split-block experiment with different fertilization treatments, including control (no fertilizer application), PK, NK, NP, NPK fertilization, in the main block, and conventional rice and hybrid rice comparison, in the sub block. Average data of five treatments in five years indicated that the indigenous N supply (INS) capacity ranged from 32.72 to 93.21 kg/ha; that indigenous P supply (IPS) capacity ranged from 7.42 to 32.25 kg/ha; and that indigenous K supply (IKS) capacity ranged from 16.24 to 140.51 kg/ha, which showed that soil available nutrient pool depletion might occur very fast and that P, K deficiency has become a constraint to increasing yields of consecutive crops grown without fertilizer application. It was found that soil nutrient deficiency and unbalanced fertilization to rice crop had negative effect on the diversity of the microbial community and total microbial biomass in the soil. The long-term fertilizer experiment (LTFE) also showed that balanced application of N, P and K promoted microbial biomass growth and improvement of community composition. Unbalanced fertilization reduced microbial N and increased C/N ratio of the microbial biomass. Compared with inbred rice, hybrid rice behavior is characterized by physiological advantage in nutrient uptake and lower internal K use efficiency. PMID:15633252

  14. Waterlogging and Plant Nutrient Uptake

    Microsoft Academic Search

    J. Theo M. Elzenga; Hans Veen

    \\u000a Waterlogging affects several parameters that determine nutrient uptake from the soil by the roots. We checked systematically,\\u000a for all the relevant parameters in the nutrient uptake model by Silberbush and Barber (Plant Soil 74:93–100, 1983), how waterlogging\\u000a changes the magnitude of the parameter, changes that can be both positive and negative for nutrient uptake. If negative effects\\u000a can be expected

  15. Soil Microbiology and Nutrient Cycling

    Microsoft Academic Search

    David W. Hopkins; Jennifer A. J. Dungait

    \\u000a Soil organisms play a central role in the recycling of nutrients in soils, making them available to plants, transforming some\\u000a nutrient elements to gaseous forms which can be lost from soil, and other transformations which predispose nutrients to loss.\\u000a In this chapter we will illustrate these processes in the context of sustainable crop production. To do so requires some consideration

  16. Estimating maize nutrient uptake requirements

    Microsoft Academic Search

    T. D. Setiyono; D. T. Walters; K. G. Cassman; C. Witt; A. Dobermann

    2010-01-01

    Generic, robust models are needed for estimating crop nutrient uptake requirements. We quantified and modeled grain yield–nutrient uptake relations in maize grown without significant biotic and abiotic stresses. Grain yield and plant nutrient accumulation in above-ground plant dry matter (DM) of commercial maize hybrids were measured at physiological maturity in on-station and on-farm experiments in Nebraska (USA), Indonesia, and Vietnam

  17. Nutrient Sensing Mechanisms and Pathways

    PubMed Central

    Efeyan, Alejo; Comb, William C.; Sabatini, David M.

    2015-01-01

    PREFACE The ability to sense and respond to fluctuations in environmental nutrient levels is a requisite for life. Nutrient scarcity is a selective pressure that has shaped the evolution of most cellular processes. Different pathways that detect intracellular and extracellular levels of sugars, amino acids and lipids, and surrogate metabolites, are then integrated and coordinated at the organismal level via hormonal signals. During food abundance, nutrient sensing pathways engage anabolism and storage, and scarcity triggers homeostatic mechanisms, like the mobilization of internal stores through mechanisms such as autophagy. Nutrient sensing pathways are commonly deregulated in human metabolic diseases. PMID:25592535

  18. Nutrient Management TrainingNutrient Management Training for Technical Service Providersfor Technical Service Providers

    E-print Network

    Nutrient Management TrainingNutrient Management Training for Technical Service Providersfor Management Planning Technical Guidance.Management Planning Technical Guidance. Manure and Wastewater Handling Nutrient ManagementNutrient Management ­­ Record KeepingRecord Keeping ­­ Feed ManagementFeed Management

  19. Preferential utilization of intracellular nutrients supports microalgal growth under nutrient starvation: multi-nutrient mechanistic model and experimental validation.

    PubMed

    Palabhanvi, Basavaraj; Kumar, Vikram; Muthuraj, Muthusivaramapandian; Das, Debasish

    2014-12-01

    Microalgae are able to grow even under exhaustion of some key nutrients such as nitrogen and phosphorous. Here, we report a multi-nutrient mechanistic model to predict heterotrophic growth of Chlorella sp. FC2 IITG over two sequential phases of fermentation: nutrient sufficient condition to nutrient starved condition. The model assumes that the growth of the microorganism takes place via sequential utilization of extracellular nutrients (ECN) under nutrient replete condition followed by intracellular stored nutrients under exhaustion of limiting nutrients. Further, intracellular nutrient was assumed to be in three different forms: structural form of nutrient (SFN), readily utilizable nutrient (RUN) and non-readily utilizable nutrient (Non-RUN). After the exhaustion of ECN, microorganism switches to RUN followed by Non-RUN to continue its growth, which was experimentally validated by extracting intracellular nitrate and phosphate compounds. The model also incorporates variability in yield coefficients for nitrate and phosphate utilizations. PMID:25305655

  20. Nutrient Removal in Wastewater Treatment

    ERIC Educational Resources Information Center

    Shah, Kanti L.

    1973-01-01

    Discusses the sources and effects of nutrients in wastewater, and the methods of their removal in wastewater treatment. In order to conserve water resources and eliminate the cost of nutrient removal, treated effluent should be used wherever possible for irrigation, since it contains all the ingredients for proper plant growth. (JR)

  1. Energy and Nutrient Intake Monitoring

    NASA Technical Reports Server (NTRS)

    Luckey, T. D.; Venugopal, B.; Hutcheson, D. P.

    1975-01-01

    A passive system to determine the in-flight intake of nutrients is developed. Nonabsorbed markers placed in all foods in proportion to the nutrients selected for study are analyzed by neutron activation analysis. Fecal analysis for each market indicates how much of the nutrients were eaten and apparent digestibility. Results of feasibility tests in rats, mice, and monkeys indicate the diurnal variation of several markers, the transit time for markers in the alimentary tract, the recovery of several markers, and satisfactory use of selected markers to provide indirect measurement of apparent digestibility. Recommendations are provided for human feasibility studies.

  2. Plant hormones and nutrient signaling

    Microsoft Academic Search

    Vicente Rubio; Regla Bustos; María Luisa Irigoyen; Ximena Cardona-López; Mónica Rojas-Triana; Javier Paz-Ares

    2009-01-01

    Plants count on a wide variety of metabolic, physiological, and developmental responses to adapt their growth to variations\\u000a in mineral nutrient availability. To react to such variations plants have evolved complex sensing and signaling mechanisms\\u000a that allow them to monitor the external and internal concentration of each of these nutrients, both in absolute terms and\\u000a also relatively to the status

  3. N-P-K balance in a milk production system on a C. nlemfuensis grassland and a biomass bank of P. purpureum CT-115 clone

    NASA Astrophysics Data System (ADS)

    Crespo, G.; Rodriguez, I.; Martinez, O.

    2009-04-01

    In very intensive milk production systems in Europe and America with the use of high amounts of chemical fertilizers, the nutrient recycling models consider the losses by leaching and N volatilization, as well as the hydro physical characteristics of the soil affecting the performance of this element (10; 6). However, in more extensive milk production systems, low input agriculture forming the natural cycle occurring within each farm, is of vital importance to potentate nutrient recycling for a stable animal production. The objective is the determination of the values of N, P and K inputs and outputs in a dairy farm with a sward composed by 60% of C. nlemfuensis and 40% of P. purpureum CT-115, associated with legumes in 28% of the area and the balance of these nutrients in the system using the "Recycling" software proposed by Crespo et al (2007). The grassland covered an area of 53.4 ha, composed by C. nlemfuensis (60%), P. purpureum CT-115 (40%) and L. leucocephala and C. cajan legumes intercropped in 28% of the area. The dairy herd consisted of 114 cows, 35 replacement heifers and 24 calves. There was a milk yield of 100 000 litters and the animals consumed 825 t DM from pastures and 75.1 t DM from other supplementary feeds. Nutrients extracted by pastures, nutrients intake by animals from pastures, symbiotically N fixation by legumes and N, P and K determinations outside the system due to animal production were determined (3-11). Volatilized ammonia, nutrient input and litter accumulated in the paddocks were measured once each season of the year. In the whole system the balance indicates negative values of N, P and K. Out of the total amount of nutrients consumed, animals used only 16 kg N, 5 Kg P and 4 Kg K for milk production, LW gain and calf production, the remainder returned to the system through excretions. Hence, more than 90% of the N and K, and approximately 81% of the P consumed by the animals were recycled to the system through the excretions. These results agree with those reported by Jarvis (1993) and Cadish et al (1994). However, 40% of the excretions occurred in the shade buildings and milking parlours ant thus these nutrients did not recycle in the system. An important internal recycling mechanism, especially for nitrogen and potassium, is their remobilization by the rejected pasture to re-use them for the regrowth activity. This is of particular interest in CT-115 Bank, since stems of CT-115 plants left after grazing remobilize an important amount of these nutrients, guarantee a favourable pasture regrowth (Martinez 1996). The return of all the excretion to the grassland is recommended as well as increasing the area of legumes to attain a satisfactory balance of N, P and K in the system. Further studies must consider maintenance fertilization, nutrient losses due to leaching and denitrification, as well as variation of the stable OM in the soil and the influence of hydro physical properties in the recycling process. The "Recycling" software was effective to determine the balance of nutrients in the dairy farm. Cadish, G., Schunke, R.N & Giller, K.E. 1994. Nitrogen cycling in a pure grass pasture and a grass-legume mixture on a red latosol in Brazil. Tropical Grasslands 28:43. Crespo G. y Rodríguez, I. 2006. Contribución al conocimiento del reciclaje de los nutrientes en el sistema suelo-pasto-animal. Instituto de Ciencia Animal, Editorial EDICA, La Habana, Cuba, 94 pp. Hirata, M., Sugimoto, Y.G & Ueno, M.1991. Use of a mathematical model to evaluate the effects of dung from grazing animals on pasture production. J. Japan Grassld. Sci. 37:303.

  4. Nutrient-sensing mechanisms across evolution.

    PubMed

    Chantranupong, Lynne; Wolfson, Rachel L; Sabatini, David M

    2015-03-26

    For organisms to coordinate their growth and development with nutrient availability, they must be able to sense nutrient levels in their environment. Here, we review select nutrient-sensing mechanisms in a few diverse organisms. We discuss how these mechanisms reflect the nutrient requirements of specific species and how they have adapted to the emergence of multicellularity in eukaryotes. PMID:25815986

  5. Nutrient limitations on peat decomposition and nutrient loading in Atlantic White Cedar swamps

    E-print Network

    Vallino, Joseph J.

    Nutrient limitations on peat decomposition and nutrient loading in Atlantic White Cedar swamps examined the effects of nutrient increases on peat decomposition. I analyzed peat and porewater nutrients of surface water nutrients. The initial C:N and C:P ratios of the peat were higher than the molar ratios

  6. Nutrient-plankton models with nutrient recycling S. R.-J. Jang1

    E-print Network

    Baglama, James

    Nutrient-plankton models with nutrient recycling S. R.-J. Jang1 and J. Baglama2 1. Department with general uptake functions in which nutrient recycling is either instantaneous or de- layed is considered in both the instantaneous and the delayed nutrient recycling models. However, the delayed nutrient

  7. Ubiquitination in plant nutrient utilization

    PubMed Central

    Yates, Gary; Sadanandom, Ari

    2013-01-01

    Ubiquitin (Ub) is well-established as a major modifier of signaling in eukaryotes. However, the extent to which plants rely on Ub for regulating nutrient uptake is still in its infancy. The main characteristic of ubiquitination is the conjugation of Ub onto lysine residues of acceptor proteins. In most cases the targeted protein is rapidly degraded by the 26S proteasome, the major proteolysis machinery in eukaryotic cells. The Ub-proteasome system is responsible for removing most abnormal peptides and short-lived cellular regulators, which, in turn, control many processes. This allows cells to respond rapidly to intracellular signals and changing environmental conditions. This perspective will discuss how plants utilize Ub conjugation for sensing environmental nutrient levels. We will highlight recent advances in understanding how Ub aids nutrient homeostasis by affecting the trafficking of membrane bound transporters. Given the overrepresentation of genes encoding Ub-metabolizing enzymes in plants, intracellular signaling events regulated by Ub that lead to transcriptional responses due to nutrient starvation is an under explored area ripe for new discoveries. We provide new insight into how Ub based biochemical tools can be exploited to reveal new molecular components that affect nutrient signaling. The mechanistic nature of Ub signaling indicates that dominant form of any new molecular components can be readily generated and are likely shed new light on how plants cope with nutrient limiting conditions. Finally as part of future challenges in this research area we introduce the newly discovered roles of Ub-like proteins in nutrient homeostasis. PMID:24282407

  8. Nutrient influences on leaf photosynthesis

    SciTech Connect

    Longstreth, D.J.; Nobel, P.S.

    1980-01-01

    The net rate of CO/sub 2/ uptake for leaves of Gossypium hirsutum L. was reduced when the plants were grown at low concentrations of NO/sub 3//sup -/, PO/sub 4//sup 2 -/, or K/sup +/. The water vapor conductance was relatively constant for all nutrient levels, indicating little effect on stomatal response. Although leaves under nutrient stress tended to be lower in chlorophyll and thinner, the ratio of mesophyll surface area to leaf area did not change appreciably. Thus, the reduction in CO/sub 2/ uptake rate at low nutrient levels was due to a decrease in the CO/sub 2/ conductance expressed per unit mesophyll cell wall area (g/sub CO/sup cell//sub 2/). The use of g/sub CO//sup cell//sub 2/ and nutrient levels expressed per unit of mesophyll cell wall provides a new means of assessing nutrient effects on CO/sub 2/ uptake of leaves. 14 figures, 1 table.

  9. REGIONAL CHARACTERISTICS OF NUTRIENT CONCENTRATIONS IN STREAMS AND THEIR APPLICATION TO NUTRIENT CRITERIA DEVELOPMENT

    EPA Science Inventory

    In order to establish meaningful nutrient criteria, consideration must be given to the spatial variations in geographic phenomena that cause or reflect differences in nutrient concentrations in streams. Regional differences in stream nutrient concentrations were illustrated usin...

  10. Spatial patterns of soil nutrients and groundwater levels within the Debre Mawi watershed of the Ethiopian highlands

    NASA Astrophysics Data System (ADS)

    Guzman, Christian; Tilahun, Seifu; Dagnew, Dessalegn; Zegeye, Assefe; Tebebu, Tigist; Yitaferu, Birru; Steenhuis, Tammo

    2015-04-01

    Persistent patterns of erosion have emerged in the Ethiopian highlands leading to soil and water conservation practices being implemented throughout the countryside. A common concern is the loss of soil fertility and loss of soil water. This study investigates the spatial patterns of soil nutrients and water table depths in a small sub-watershed in the northwestern Ethiopian highlands. NPK, a particularly important group of nutrients for inorganic fertilizer considerations, did not follow a consistent trend as a group along and across slope and land use transects. Whereas nitrogen content was greatest in the upslope regions (~0.1% TN), available phosphorus had comparably similar content in the different slope regions throughout the watershed (~2.7 mg/kg). The exchangeable cations (K, Ca, Mg) did increase in content in a downslope direction (in most cases though, they were highest in the middle region) but not consistently later in the season. On average, calcium (40 cmol/kg), magnesium (5 cmol/kg), and potassium (0.5 cmol/kg) were orders of magnitudes different in content. The perched water table in different areas of the watershed showed a very distinct trend. The lower part of the sub-watershed had shallower levels of water table depths (less than 10 cm from the surface) than did the upper parts of the sub-watershed (usually greater than 120 cm from the surface). The middle part of the sub-watershed had water table depths located at 40 to 70 cm below the surface. These results show how the landscape slope position and land use may be important for planning where and when soil nutrients and water would be expected to be appropriately "conserved" or stored.

  11. Chords: Em 022000 Em Em Em Em C C C C

    E-print Network

    Reiners, Peter W.

    Verse 1 Chorus Verse 2 Chorus Verse 3 Chords: Em 022000 C 035553 G 320002 F 133211 Intro: Em Em Em Em C C C C Em Em Em Em C C C C Em Em Em Em C C C C Em Em Em Em C C C C Verse: Em Em Em Em C C C C G G G G G G G G Em Em Em Em C C C C G G G G G G G G Em Em Em Em C C C C G G G G G G G G Em Em Em Em C C

  12. Influence of bio-fertilizers on the biomass yield and nutrient content in Stevia rebaudiana Bert. grown in Indian subtropics

    Microsoft Academic Search

    Kuntal Das; Raman Dang; Nazim Sekeroglu

    A pot culture experiment was conducted at Indian Institute of Horticultural Research, Hessaraghata, Bangalore, India to study the effect of bio-fertilizers on the biomass yield and NPK content in Stevia (Stevia rebaudiana). The results show the yield and NPK content in stevia plant has been found to be increased initially and thereafter, the amount of the same decreased with the

  13. Nutrient dynamics within amazonian forests

    Microsoft Academic Search

    Elvira Cuevas; Ernesto Medina

    1988-01-01

    Relationships between fine root growth, rates of litter decomposition and nutrient release were analysed in a mixed forest on Tierra Firme, a Tall Amazon Caatinga and a Low Bana on podsolized sands near San Carlos de Rio Negro. Fine root growth in the upper soil layers (root mat+10 cm upper soil) was considerably higher in the Tierra Firme forest (1117

  14. Regulating nutrient allocation in plants

    DOEpatents

    Udvardi, Michael; Yang, Jiading; Worley, Eric

    2014-12-09

    The invention provides coding and promoter sequences for a VS-1 and AP-2 gene, which affects the developmental process of senescence in plants. Vectors, transgenic plants, seeds, and host cells comprising heterologous VS-1 and AP-2 genes are also provided. Additionally provided are methods of altering nutrient allocation and composition in a plant using the VS-1 and AP-2 genes.

  15. with Comprehensive Nutrient Management Plans

    E-print Network

    Mukhtar, Saqib

    with Comprehensive Nutrient Management Plans Managing Manure and Litter on Animal Feeding of discrimination write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D and employer. April 2009 PA-2015 H elping People H elp t h e Lan d Managing Manure and Litter on Animal Feeding

  16. Hunting Nutrients and Trapping Carbon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil fertility is enhanced directly by arbuscular mycorrhizal fungi (AMF) efficiently absorbing the maximum amount of nutrients available and indirectly by formation of stabilized soil aggregates. Glomalin is sticky, not easily soluble substance, on AMF hyphae and provides a protective coating to b...

  17. Nutrients for the aging eye

    PubMed Central

    Rasmussen, Helen M; Johnson, Elizabeth J

    2013-01-01

    The incidence of age-related eye diseases is expected to rise with the aging of the population. Oxidation and inflammation are implicated in the etiology of these diseases. There is evidence that dietary antioxidants and anti-inflammatories may provide benefit in decreasing the risk of age-related eye disease. Nutrients of interest are vitamins C and E, ?-carotene, zinc, lutein, zeaxanthin, and the omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid. While a recent survey finds that among the baby boomers (45–65 years old), vision is the most important of the five senses, well over half of those surveyed were not aware of the important nutrients that play a key role in eye health. This is evident from a national survey that finds that intake of these key nutrients from dietary sources is below the recommendations or guidelines. Therefore, it is important to educate this population and to create an awareness of the nutrients and foods of particular interest in the prevention of age-related eye disease. PMID:23818772

  18. Low soil temperature inhibits the effect of high nutrient supply on photosynthetic response to elevated carbon dioxide concentration in white birch seedlings.

    PubMed

    Ambebe, Titus F; Dang, Qing-Lai; Li, Junlin

    2010-02-01

    To investigate the interactive effects of soil temperature (T(soil)) and nutrient availability on the response of photosynthesis to elevated atmospheric carbon dioxide concentration ([CO(2)]), white birch (Betula papyrifera Marsh.) seedlings were exposed to ambient (360 micromol mol(-1)) or elevated (720 micromol mol(-1)) [CO(2)], three T(soil) (5, 15 and 25 degrees C initially, increased to 7, 17 and 27 degrees C, respectively, 1 month later) and three nutrient regimes (4/1.8/3.3, 80/35/66 and 160/70/132 mg l(-1) N/P/K) for 3 months in environment-controlled greenhouses. Elevated [CO(2)] increased net photosynthetic rate (A(n)), instantaneous water-use efficiency (IWUE), internal to ambient carbon dioxide concentration ratio (C(i)/C(a)), triose phosphate utilization (TPU) and photosynthetic linear electron transport to carboxylation (J(c)), and it decreased actual photochemical efficiency of photosystem II (DeltaF/F(m)'), the fraction of total linear electron transport partitioned to oxygenation (J(o)/J(T)) and leaf N concentration. The low T(soil) suppressed A(n), transpiration rate (E), TPU, DeltaF/F(m)' and J(c), but it increased J(o)/J(T). The low nutrient treatment reduced A(n), IWUE, maximum carboxylation rate of Rubisco, light-saturated electron transport rate, TPU, DeltaF/F(m)', J(c) and leaf N concentration, but increased C(i)/C(a). There were two-factor interactions for C(i)/C(a), TPU and leaf N concentration, and a significant effect of CO(2) x T(soil) x nutrient regime on A(n), IWUE and J(c). The stimulations of A(n) and IWUE by elevated [CO(2)] were limited to seedlings grown under the intermediate and high nutrient regimes at the intermediate and high T(soil). For J(c), the [CO(2)] effect was significant only at intermediate T(soil) + high nutrient availability. No significant [CO(2)] effects were observed under the low T(soil) at any nutrient level. Our results support this study's hypothesis that low T(soil) would reduce the positive effect of high nutrient supply on the response of A(n) to elevated [CO(2)]. PMID:20007132

  19. Nutrient surpluses on integrated arable farms

    Microsoft Academic Search

    J. J. Schröder; P. van Asperen; G. J. M. van Dongen; F. G. Wijnands

    1996-01-01

    From 1990 to 1993 nutrient fluxes were monitored on 38 private arable farms that had adopted farming strategies aiming at reduced nutrient inputs and substitution of mineral fertilizers by organic fertilizers. The nutrient surplus was defined as the difference between inputs (including inputs through deposition, seeds and biological fixation) and outputs in crop products, and amounted to 117 kg nitrogen

  20. Agronomy Facts 60 NUTRIENT MANAGEMENT PLANNING

    E-print Network

    Kaye, Jason P.

    to produce a crop. More recently, nutrient management also has begun to address ways to minimize the negative 14 Sow and 8 14 Sheep 23 Horse 12 Poultry Layer 37 Pullet 43 20 Nutrient Management Plan Crop Manure not apply the nutrient of greatest environmental concern in excess of the crop needs. Best management

  1. Nutrient Content of Single – Muscle Pork Cuts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The two objectives of this study were to determine the nutrient profiles of four fresh pork cuts (fabricated from individual muscles extracted from subprimals) for dissemination in the USDA National Nutrient Database for Standard Reference (SR) and determine cooking yields and nutrient retention fac...

  2. Nutrient transport in the Humber rivers

    Microsoft Academic Search

    W. A. House; D. Leach; M. S. Warwick; B. A. Whitton; S. N. Pattinson; G. Ryland; A. Pinder; J. Ingram; J. P. Lishman; S. M. Smith; E. Rigg; F. H. Denison

    1997-01-01

    The results of the weekly and storm sample measurement of the nutrient concentrations in ten Humber rivers over one annual cycle are presented. The nutrients include soluble reactive phosphorus (SRP), total dissolved phosphorus (TDP), total phosphorus (TP), nitrate and silicon (soluble reactive silicon). These data are combined with the river discharge data to calculate the nutrient loads discharged into the

  3. Nutrient quality of fast food kids meals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure of children to kids’ meals at fast food restaurants is high; however, the nutrient quality of such meals has not been systematically assessed. We assessed the nutrient quality of fast food meals marketed to young children, i.e., "kids meals". The nutrient quality of kids’ meals was assessed...

  4. NUTRIENT CRITERIA DEVELOPMENT FOR R10 ECOREGIONS.

    EPA Science Inventory

    Excess nutrients in waters of the northwest are one of the top contributors to water quality impairment. EPA, states and Tribes lack quantifiable targets for nutrients in the water quality standards. Water quality standards for nutrients usually use narrative language, such as ...

  5. Persistence in variable-yield nutrient-plankton models with nutrient recycling

    E-print Network

    Baglama, James

    Persistence in variable-yield nutrient-plankton models with nutrient recycling Sophia Jang1's by Riley et al. [24] for modeling the profiles of marine plankton. Since then numerious nutrient-plankton, 29, 30, 34, 35]. The intensive investigation of nutrient-plankton interactions is motivated in large

  6. Growth, nutrient absorption, and moisture status of selected woody species in coal mine spoil in response to an induced infection by the ectomycorrhizal fungus Pisolithus tinctorius

    SciTech Connect

    Walker, R.F.

    1982-01-01

    The growth, nutrient absorption, and internal moisture status of selected woody species in coal mine spoil in response to an induced infection by the ectomycorrhizal fungus Pisolithus tinctorius was studied. Nursery grown loblolly and Virginia pine seedlings infected with Pisolithus and control seedlings were outplanted on a coal mine spoil in Tennessee which had been previously hydroseeded with a mixture of herbaceous ground cover species. Granular fertilizer was applied by broadcasting to one-half of the seedlings of each ectomycorrhizal treatment at the rate of 112 kg/ha NPK. After three years, the survival and growth of loblolly pine infected with Pisolithus was superior to that of the control seedlings, and chemical analyses of foliar samples revealed that the seedlings with Pisolithus ectomycorrhizae had a higher foliar concentration of NO/sub 3/ and a lower concentration of Zn than the control seedlings. The survival, growth, and nutrient absorption of Virginia pine were not significantly affected by the infection with Pisolithus after two years, but both loblolly and Virginia pine seedlings with Pisolithus ectomycorrhizae exhibited an enhanced ability to absorb water during periods of high moisture stress, as determined by the pressure chamber technique. Fertilization substantially reduced the survival of the seedlings of both species.

  7. Nutrient Shielding in Clusters of Cells

    E-print Network

    Maxim O. Lavrentovich; John H. Koschwanez; David R. Nelson

    2013-06-13

    Cellular nutrient consumption is influenced by both the nutrient uptake kinetics of an individual cell and the cells' spatial arrangement. Large cell clusters or colonies have inhibited growth at the cluster's center due to the shielding of nutrients by the cells closer to the surface. We develop an effective medium theory that predicts a thickness $\\ell$ of the outer shell of cells in the cluster that receives enough nutrient to grow. The cells are treated as partially absorbing identical spherical nutrient sinks, and we identify a dimensionless parameter $\

  8. Nutrient control of Drosophila longevity.

    PubMed

    Tatar, Marc; Post, Stephanie; Yu, Kweon

    2014-10-01

    Dietary restriction (DR) extends the lifespan of many animals, including Drosophila melanogaster. Recent work with flies shows that longevity is controlled by the ratio of consumed protein relative to carbohydrates. Given that reduced insulin and/or insulin-like growth factor (IGF) and target of rapamycin (TOR) signaling increase Drosophila lifespan, these pathways are candidate mediators of DR. However, this idea has ambiguous experimental support. The Nutritional Geometric Framework (NGF), which dissects the impact of nutrient protein relative to carbohydrates, may provide an approach to resolving the roles for these pathways in DR. Nutrient sensing of protein and carbohydrate may occur in the fat body through signals to hypothalamic-like neurons in the fly brain and, thus, control secretion of insulin-like peptides that regulate longevity. PMID:24685228

  9. Automated nutrient analyses in seawater

    SciTech Connect

    Whitledge, T.E.; Malloy, S.C.; Patton, C.J.; Wirick, C.D.

    1981-02-01

    This manual was assembled for use as a guide for analyzing the nutrient content of seawater samples collected in the marine coastal zone of the Northeast United States and the Bering Sea. Some modifications (changes in dilution or sample pump tube sizes) may be necessary to achieve optimum measurements in very pronounced oligotrophic, eutrophic or brackish areas. Information is presented under the following section headings: theory and mechanics of automated analysis; continuous flow system description; operation of autoanalyzer system; cookbook of current nutrient methods; automated analyzer and data analysis software; computer interfacing and hardware modifications; and trouble shooting. The three appendixes are entitled: references and additional reading; manifold components and chemicals; and software listings. (JGB)

  10. Rhizosphere priming: a nutrient perspective.

    PubMed

    Dijkstra, Feike A; Carrillo, Yolima; Pendall, Elise; Morgan, Jack A

    2013-01-01

    Rhizosphere priming is the change in decomposition of soil organic matter (SOM) caused by root activity. Rhizosphere priming plays a crucial role in soil carbon (C) dynamics and their response to global climate change. Rhizosphere priming may be affected by soil nutrient availability, but rhizosphere priming itself can also affect nutrient supply to plants. These interactive effects may be of particular relevance in understanding the sustained increase in plant growth and nutrient supply in response to a rise in atmospheric CO2 concentration. We examined how these interactions were affected by elevated CO2 in two similar semiarid grassland field studies. We found that an increase in rhizosphere priming enhanced the release of nitrogen (N) through decomposition of a larger fraction of SOM in one study, but not in the other. We postulate that rhizosphere priming may enhance N supply to plants in systems that are N limited, but that rhizosphere priming may not occur in systems that are phosphorus (P) limited. Under P limitation, rhizodeposition may be used for mobilization of P, rather than for decomposition of SOM. Therefore, with increasing atmospheric CO2 concentrations, rhizosphere priming may play a larger role in affecting C sequestration in N poor than in P poor soils. PMID:23908649

  11. Growth and Nutrient Uptake by Soybean Plants in Nutrient Solutions of Graded Concentrations

    PubMed Central

    Leggett, James E.; Frere, Maurice H.

    1971-01-01

    Soybean plants (Glycine max L. Merr. var. Hawkeye), grown in nutrient solutions maintained at graded concentrations showed a large response in both shoot dry weight and total ion uptake. Growth rate was dependent upon nutrient concentration, even when quantity of nutrient was not limiting. Peak periods for absorption of specific ions at certain growth stages were not exhibited. Rates of ion uptake by soybeans were generally proportional to the growth rate during the period of major growth. It is suggested that a dilute nutrient solution could provide sufficient nutrients for adequate root growth prior to major shoot growth, at which time a more concentrated nutrient solution is needed. PMID:16657819

  12. Adaptability of growth and nutrient uptake potential of Chlorella sorokiniana with variable nutrient loading.

    PubMed

    Shriwastav, Amritanshu; Gupta, Sanjay Kumar; Ansari, Faiz Ahmad; Rawat, Ismail; Bux, Faizal

    2014-12-01

    Chlorella sorokiniana can sustain growth in conditions hostile to other species, and possesses good nutrient removal and lipid accumulation potentials. However, the effects of variable nutrient levels (N and P) in wastewaters on growth, productivity, and nutrient uptake by C. sorokiniana have not been studied in detail. This study demonstrates the ability of this alga to sustain uniform growth and productivity, while regulating the relative nutrient uptake in accordance to their availability in the bulk medium. These results highlight the potential of C. sorokiniana as a suitable candidate for fulfilling the coupled objectives of nutrient removal and biomass production for bio-fuel with wastewaters having great variability in nutrient levels. PMID:25463782

  13. Insects, infestations and nutrient fluxes

    NASA Astrophysics Data System (ADS)

    Michalzik, B.

    2012-04-01

    Forest ecosystems are characterized by a high temporal and spatial variability in the vertical transfer of energy and matter within the canopy and the soil compartment. The mechanisms and controlling factors behind canopy processes and system-internal transfer dynamics are imperfectly understood at the moment. Seasonal flux diversities and inhomogeneities in throughfall composition have been reported from coniferous and deciduous forests, and in most cases leaf leaching has been considered as principle driver for differences in the amount and quality of nutrients and organic compounds (Tukey and Morgan 1963). Since herbivorous insects and the processes they initiate received less attention in past times, ecologists now emphasize the need for linking biological processes occurring in different ecosystem strata to explain rates and variability of nutrient cycling (Bardgett et al. 1998, Wardle et al. 2004). Consequently, herbivore insects in the canopies of forests are increasingly identified to play an important role for the (re)cycling and availability of nutrients, or, more generally, for the functioning of ecosystems not only in outbreak situations but also at endemic (non-outbreak) density levels (Stadler et al. 2001, Hunter et al. 2003). Before, little attention was paid to insect herbivores when quantifying element and energy fluxes through ecosystems, although the numerous and different functions insects fulfill in ecosystems (e.g. as pollinators, herbivores or detritivores) were unanimously recognized (Schowalter 2000). Amongst the reasons for this restraint was the argument that the total biomass of insects tends to be relatively low compared to the biomass of trees or the pool of soil organic matter (Ohmart et al. 1983). A second argument which was put forward to justify the inferior role of insects in nutrient cycling were the supposed low defoliation losses between 5-10% of the annual leaf biomass, or net primary production, due to insect herbivory under endemic situations (Larrson and Tenow 1980). However, at times of insect mass outbreaks with leaf area losses up to 100%, nutrient fluxes are strongly affected at the ecosystem level and consequently attract greater attention (Grace 1986). In this context, mass outbreaks of herbivore insects constitute a class of ecosystem disturbance (Pickett and White 1985). More specific, insect pests meet the criteria of biogeochemical "hot spots" and "hot moments" (McClain et al. 2003) as they induce temporal-spatial process heterogeneity or changes in biogeochemical reaction rates, but not necessarily changes in the structure of ecosystems or landscapes. This contribution presents a compilation of literature and own research data on insect herbivory effects on nutrient cycling and ecosystem functioning from the plot to the catchment scale. It focuses on temperate forest ecosystems and on short-term impacts as exerted by two focal functional groups of herbivore canopy insects (leaf and sap feeders). In detail, research results on effects operating on short temporal scales are presented including a) alterations in throughfall fluxes encompassing dissolved and particulate organic matter fractions, b) alterations in the amount, timing and quality of frass and honeydew deposition and c) soil microbial activity and decomposition processes.

  14. Managing urban nutrient biogeochemistry for sustainable urbanization.

    PubMed

    Lin, Tao; Gibson, Valerie; Cui, Shenghui; Yu, Chang-Ping; Chen, Shaohua; Ye, Zhilong; Zhu, Yong-Guan

    2014-09-01

    Urban ecosystems are unique in the sense that human activities are the major drivers of biogeochemical processes. Along with the demographic movement into cities, nutrients flow towards the urban zone (nutrient urbanization), causing the degradation of environmental quality and ecosystem health. In this paper, we summarize the characteristics of nutrient cycling within the urban ecosystem compared to natural ecosystems. The dynamic process of nutrient urbanization is then explored taking Xiamen city, China, as an example to examine the influence of rapid urbanization on food sourced nitrogen and phosphorus metabolism. Subsequently, the concept of a nutrient footprint and calculation method is introduced from a lifecycle perspective. Finally, we propose three system approaches to mend the broken biogeochemical cycling. Our study will contribute to a holistic solution which achieves synergies between environmental quality and food security, by integrating technologies for nutrient recovery and waste reduction. PMID:24746891

  15. USDA Nutrient Database for Standard Reference (SR)

    NSDL National Science Digital Library

    The Nutrient Data Laboratory of the US Agricultural Research Service has announced Release 12 of the Nutrient Database for Standard Reference (discussed in the October 15, 1997 Scout Report for Science and Engineering). The data can be searched and viewed from the home page or downloaded in several different formats. The Database contains information on food groups, nutrient content, weights, measures and source footnotes. Over 5,900 foods are included and full file documentation is available.

  16. Control of microorganisms in flowing nutrient solutions

    NASA Astrophysics Data System (ADS)

    Evans, R. D.

    1994-11-01

    Controlling microorganisms in flowing nutrient solutions involves different techniques when targeting the nutrient solution, hardware surfaces in contact with the solution, or the active root zone. This review presents basic principles and applications of a number of treatment techniques, including disinfection by chemicals, ultrafiltration, ultrasonics, and heat treatment, with emphasis on UV irradiation and ozone treatment. Procedures for control of specific pathogens by nutrient solution conditioning also are reviewed.

  17. Nutrient availability moderates transpiration in Ehrharta calycina.

    PubMed

    Cramer, Michael D; Hoffmann, Vera; Verboom, G Anthony

    2008-01-01

    Transpiration-driven 'mass-flow' of soil-water can increase nutrient flow to the root surface. Here it was investigated whether transpiration could be partially regulated by nutrient status. Seeds of Ehrharta calycina from nine sites across a rainfall gradient were supplied with slow-release fertilizer dibbled into the sand surrounding the roots and directly available through interception, mass-flow and diffusion (dubbed 'interception'), or sequestered behind a 40-microm mesh and not directly accessible by the roots, but from which nutrients could move by diffusion or mass-flow (dubbed 'mass-flow'). Although mass-flow plants were significantly smaller than interception plants as a consequence of nutrient limitation, they transpired 60% faster, had 90% higher photosynthesis relative to transpiration (A/E), and 40% higher tissue P, Ca and Na concentrations than plants allowed to intercept nutrients directly. Tissue N and K concentrations were similar for interception and mass-flow plants. Transpiration was thus higher in the nutrient-constrained 'mass-flow' plants, increasing the transport of nutrients to the roots by mass-flow. Transpiration may have been regulated by N availability, resulting in similar tissue concentration between treatments. It is concluded that, although transpiration is a necessary consequence of photosynthetic CO(2) uptake in C(3) plants, plants can respond to nutrient limitation by varying transpiration-driven mass-flow of nutrients. PMID:18537891

  18. NUTRIENT UPTAKE: A Microcomputer Program to Predict Nutrient Absorption from Soil by Roots.

    ERIC Educational Resources Information Center

    Oates, Kenneth; Barber, S. A.

    1987-01-01

    Discusses the use of a computer program designed to solve the mathematical model associated with soil nutrient uptake by plant roots and to predict the nutrient uptake. Describes a user-friendly personal computer version of this program. (TW)

  19. Rhizosphere Priming: a Nutrient Perspective

    NASA Astrophysics Data System (ADS)

    Dijkstra, F. A.; Carrillo, Y.; Pendall, E. G.; Morgan, J. A.

    2013-12-01

    Rhizosphere priming is the change in decomposition of soil organic matter (SOM) caused by root activity. Rhizosphere priming plays a crucial role in soil carbon (C) dynamics and their response to global climate change. Rhizosphere priming may be affected by soil nutrient availability, but rhizosphere priming itself can also affect nutrient supply to plants. We postulate that rhizosphere priming on soil C may occur in nitrogen (N) limited but not in phosphorus (P) limited systems. Under N limitation, root exudates may be utilised by microbes stimulating oxidation of soil C thereby releasing N. On the other hand, under P limitation, rhizodeposition may be used for P hydrolysis, desorption, dissolution and mobilisation processes without affecting C decomposition. We illustrate this hypothesis with results from two field experiments in semiarid grasslands (Colorado and Wyoming study) affected by elevated atmospheric CO2. We found that an increase in rhizosphere priming under elevated CO2 enhanced the release of N through decomposition of a larger fraction of SOM in the Colorado study, but not in the Wyoming study. This contrast in N cycling may have been caused by N limitation in the Colorado and P limitation in the Wyoming study. Therefore, with increasing atmospheric CO2 concentrations, rhizosphere priming may play a larger role in affecting C sequestration in N poor than in P poor soils.

  20. Eutrophication of Buttermilk Bay, a cape cod coastal embayment: Concentrations of nutrients and watershed nutrient budgets

    Microsoft Academic Search

    Ivan Valiela; Joseph E. Costa

    1988-01-01

    Nutrient concentrations in Buttermilk Bay, a coastal embayment on the northern end of Buzzards Bay, MA, are higher in the nearshore where salinities are lower. This pattern suggests that freshwater sources may contribute significantly to nutrient inputs into Buttermilk Bay. To evaluate the relative importance of the various sources we estimated inputs of nutrients by each major source into the

  1. Nutrient profiling of foods: creating a nutrient-rich food index

    Microsoft Academic Search

    Adam Drewnowski; Victor Fulgoni

    2008-01-01

    Nutrient profiling of foods, described as the science of ranking foods based on their nutrient content, is fast becoming the basis for regulating nutrition labels, health claims, and marketing and advertising to children. A number of nutrient profile models have now been developed by research scientists, regulatory agencies, and by the food industry. Whereas some of these models have focused

  2. Root morphological plasticity and nutrient acquisition of perennial grass species from habitats of different nutrient availability

    Microsoft Academic Search

    Bart Fransen; Hans de Kroon; Frank Berendse

    1998-01-01

    We studied the root foraging ability and its consequences for the nutrient acquisition of five grass species that differ ill relative growth rate and that occur in habitats that differ widely in nutrient availability. Foraging responses were quantified, based on the performance of the plants in homogeneous and heterogeneous soil environments of the same overall nutrient availability. Although all species

  3. Ecosystem functioning in the German bight under continental nutrient inputs by rivers

    SciTech Connect

    Radach, G. (Universitaet Hamburg (Germany))

    1992-12-01

    The functioning of the German Bight ecosystem is determined largely by nutrient fluxes in and out of the system from the central and southern North Sea; by nutrient inputs through direct continental river runoff into the German Bight (Elbe, Weser, and Ems rivers); and by atmospheric nutrient inputs originating from land. The nutrient situation is assessed by estimating from available data. For the entire North Sea, the total input of phosphorus increased by 7.7% and nitrogen by about 11.4% from 1950 to 1980. The percentage of Atlantic input of phosphorus into the entire North Sea decreased from 91% to 85%, while river input increased from 2% to 13%. In the continental coastal strip the total inputs increased by 80%. The share of river input increased to 52%, both for phosphorus (1950: 14%) and nitrogen (1950: 20%). Of the winter nutrient content of the upper 30 m of the North Sea 33.5% of phosphate and 16.1% of nitrate are taken up by algae until summer. About 50% of total new production is generated in the coastal areas, with 32.8% of the volume and 34.4% of the area of the North Sea. In the German Bight, phosphate and nitrate concentrations increased during the last four decades. At Helgoland the five-year-medians of phosphate and nitrate increased by a factor of 1.7 and 2.5, respectively. As the nutrient inputs by river discharges are only slightly larger than advective contributions, the nutrient concentrations rose comparatively slowly. Diatoms stagnated and flagellates increased 10-fold. Common winter values in the early 1980s resemble those during summer blooms in the early 1960's. The German Bight ecosystem has changed drastically on all time scales under the anthropogenic nutrient inputs during the last 40 years; the plankton system is no longer in an annual quasiperiodic state.54 refs., 13 figs., 5 tabs.

  4. Nutrient dynamics and food-web stability

    Microsoft Academic Search

    D. L. DeAngelis; P. J. Mulholland; A. V. Palumbo; A. D. Steinman; M. A. Huston; J. W. Elwood

    1989-01-01

    The importance of nutrient limitation and recycling in ecosystems is widely recognized. Nutrients, defined in the broad sense as all material elements vital to biological functions, are in such small supply that they limit production in many ecosystems. Such limitation can affect ecosystem properties, including the structure and dynamics of the food webs that link species through their feeding relationships.

  5. EFFECT OF NUTRIENT INTAKE ON PREMENSTRUAL DEPRESSION

    E-print Network

    Wurtman, Richard

    EFFECT OF NUTRIENT INTAKE ON PREMENSTRUAL DEPRESSION JUDITHJ. WURTMAN,PhD, AMNONBRZEZINSKI and Qognitive Sciences. Massachusetts Institute of Technology. Reprinted from AMERICAN JOURNAL OF OBSTETRICS) (Printed in the U.S.A.) -- - ----- #12;Effect of nutrient intake on premenstrual depression Judith J

  6. Agronomy Facts 38-A A Nutrient Management

    E-print Network

    Kaye, Jason P.

    with supplying and managing nutrients to meet crop production requirements. The predictable response of a crop management for crop production and environmental protection means that nutri- ent management considerationsAgronomy Facts 38-A A Nutrient Management Approach for Pennsylvania: Introduction to the Concepts

  7. NUTRIENT-UPTAKE MODEL IN MARSH ECOSYSTEMS

    EPA Science Inventory

    Mechanistic models of nutrient dynamics in natural wetlands were developed and applied in a study of Kissimmee River (Florida) flood-plain marshes. The models describe hydrodynamics and transport diffusion in wetland basins and the ecological processes of nutrient uptake, convers...

  8. The Nutrient Profile in Organic Fertilizers

    Microsoft Academic Search

    Martin S. Kumar; Le Thanh Luu; Mai Van Ha; Nguyen Quang Dieu

    2005-01-01

    In order to manage nitrogen (N) and phosphorous (P) through organic fertilization in aquaculture ponds, it is important to understand the nutrient profile of different animal manures at various concentrations and the respective biological response. The rate of nutrient released from animal manure over time is a key factor in deciding the frequency and quantity of manure required to fertilize

  9. Dairy Manure Nutrients: Variable, But Valuable

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowing the nutrient content of manure is essential for doing nutrient management planning for dairy farms. Summaries of over 14,000 dairy manure samples from Wisconsin and 2,300 from Vermont over a 10 to 15-year period showed average values that were consistent with UW-Extension book values but dif...

  10. Absorption of nutrients in lactase deficiency

    Microsoft Academic Search

    J. C. Debongnie; A. D. Newcomer; D. B. McGill; S. F. Phillips

    1979-01-01

    The influence of malabsorption of lactose, as a result of primary lactase deficiency, on the absorption of the nutrients in milk was tested in four healthy controls and four subjects with lactase deficiency. An ileal perfusion technique was used to quantify arrival in the ileum of nutrients and a nonabsorbable marker (polyethylene glycol, PEG 4000) ingested as a test meal

  11. REMEDIATION TECHNIQUES FOR MANURE NUTRIENT LOADED SOILS

    Microsoft Academic Search

    Hailin Zhang; Thanh H. Dao; Nicholas T. Basta; Elizabeth A. Dayton; Tommy C. Daniel

    SUMMARY Many soils in the United States contain excessive levels of nutrients, especially phosphorus (P), due to repeated heavy applications of animal manure. Also, soils with a history of long-term poultry litter or swine manure applications have elevated levels of copper (Cu), zinc (Zn), selenium (Se), and arsenic (As). Runoff and eroded soils carry dissolved and sediment-associated nutrients to wa-

  12. A Nutrient Sensor Mechanism Controls Drosophila Growth

    Microsoft Academic Search

    Julien Colombani; Sophie Raisin; Sophie Pantalacci; Thomas Radimerski; Jacques Montagne; Pierre Léopold

    2003-01-01

    Organisms modulate their growth according to nutrient availability. Although individual cells in a multicellular animal may respond directly to nutrient levels, growth of the entire organism needs to be coordinated. Here, we provide evidence that in Drosophila, coordination of organismal growth originates from the fat body, an insect organ that retains endocrine and storage functions of the vertebrate liver. In

  13. NUTRIENTS IN WATERSHEDS; DEVELOPING ENHANCED MODELING TOOLS

    EPA Science Inventory

    Nutrient enrichment is one of the most detrimental stressors causing water-resource impairment. Of systems surveyed and reported as impaired, 40% of rivers, 51% of lakes, and 57% of estuaries listed nutrients as a primary cause of impairment (USEPA, 1996). In many cases, these ...

  14. Processes and patterns of oceanic nutrient limitation

    NASA Astrophysics Data System (ADS)

    Moore, C. M.; Mills, M. M.; Arrigo, K. R.; Berman-Frank, I.; Bopp, L.; Boyd, P. W.; Galbraith, E. D.; Geider, R. J.; Guieu, C.; Jaccard, S. L.; Jickells, T. D.; La Roche, J.; Lenton, T. M.; Mahowald, N. M.; Marañón, E.; Marinov, I.; Moore, J. K.; Nakatsuka, T.; Oschlies, A.; Saito, M. A.; Thingstad, T. F.; Tsuda, A.; Ulloa, O.

    2013-09-01

    Microbial activity is a fundamental component of oceanic nutrient cycles. Photosynthetic microbes, collectively termed phytoplankton, are responsible for the vast majority of primary production in marine waters. The availability of nutrients in the upper ocean frequently limits the activity and abundance of these organisms. Experimental data have revealed two broad regimes of phytoplankton nutrient limitation in the modern upper ocean. Nitrogen availability tends to limit productivity throughout much of the surface low-latitude ocean, where the supply of nutrients from the subsurface is relatively slow. In contrast, iron often limits productivity where subsurface nutrient supply is enhanced, including within the main oceanic upwelling regions of the Southern Ocean and the eastern equatorial Pacific. Phosphorus, vitamins and micronutrients other than iron may also (co-)limit marine phytoplankton. The spatial patterns and importance of co-limitation, however, remain unclear. Variability in the stoichiometries of nutrient supply and biological demand are key determinants of oceanic nutrient limitation. Deciphering the mechanisms that underpin this variability, and the consequences for marine microbes, will be a challenge. But such knowledge will be crucial for accurately predicting the consequences of ongoing anthropogenic perturbations to oceanic nutrient biogeochemistry.

  15. Nutrient dynamics and food-web stability

    SciTech Connect

    DeAngelis, D.L.; Mulholland, P.J.; Palumbo, A.V.; Steinman, A.D.; Huston, M.A.; Elwood, J.W. (Environmental Sciences Div., Oak Ridge National Lab., Oak Ridge, TN (US))

    1989-01-01

    The importance of nutrient limitation and recycling in ecosystems is widely recognized. Nutrients, defined in the broad sense as all material elements vital to biological functions, are in such small supply that they limit production in many ecosystems. Such limitation can affect ecosystem properties, including the structure and dynamics of the food webs that link species through their feeding relationships. What are the effects of limiting nutrients on the stability of ecosystem food webs Most of the literature on food web stability centers around the dynamics of population numbers and/or biomasses. Nevertheless, a growing body of theoretical and empirical research considers the role that both nutrient limitation and recycling can play in stability. In this paper, it is the authors objective to summarize the current understanding of several important types of stability. The theoretical and empirical evidence relating these types of stability and nutrient cycling is described. A central generalization is produced in each case.

  16. ORIGINAL PAPER Implication of nutrient and salinity interaction

    E-print Network

    ORIGINAL PAPER Implication of nutrient and salinity interaction on the productivity of Spartina nutrient availability and reduced salinity. Although studies have documented nutrient limitation and salinity stress in coastal marshes, interpreting the effects of freshwater rein- troduction on plant

  17. Version 2.1 January 2012 Nutrient Balance Sheet

    E-print Network

    Kaye, Jason P.

    Version 2.1 ­ January 2012 Nutrient Balance Sheet Prepared For Operator's Name Operator's Address _________________________________ County of Origin _____________________________________ Nutrient Balance Worksheet Appendices The following appendices need to accompany the Nutrient Balance Worksheets if applicable: · Maps of fields where

  18. Linking nutrient enrichment, sediment erodibility and biofilms

    NASA Astrophysics Data System (ADS)

    Conrad, B.; Mahon, R.; Sojka, S. L.

    2014-12-01

    Sediment movement in coastal lagoons affects nutrient flux and primary producer growth. Previous research has shown that sediment erodibility is affected by biofilm concentration and that growth of benthic organisms, which produce biofilm, is affected by nutrient enrichment. However, researchers have not examined possible links between nutrient addition and sediment erodibility. We manipulated nutrient levels in the water column of 16 microcosms filled with homogenized sediment from a shallow coastal lagoon and artificial seawater to determine the effects on biofilm growth, measured through chlorophyll a and colloidal carbohydrate concentrations. Erosion tests using a Gust microcosm were conducted to determine the relationship between sediment erodibility and biofilm concentration. Results show that carbohydrate levels decreased with increasing nutrient enrichment and were unrelated to chlorophyll concentrations and erodibility. The nutrient levels did not predictably affect the chlorophyll levels, with lower chlorophyll concentrations in the control and medium enrichment treatments than the low and high enrichment treatments. Controls on biofilm growth are still unclear and the assumed relationship between carbohydrates and erodibility may be invalid. Understanding how biofilms respond to nutrient enrichment and subsequent effects on sediment erodibility is essential for protecting and restoring shallow coastal systems.

  19. Carnitine as an essential nutrient.

    PubMed

    Borum, P R; Bennett, S G

    1986-01-01

    Carnitine performs a critically important role in energy metabolism and is synthesized in the healthy adult predominantly in the liver and kidney. The typical well balanced American diet contains significant amounts of carnitine as well as the essential amino acids and micronutrients needed for carnitine biosynthesis. Thus carnitine is an infrequent problem in the healthy, well nourished adult population in the United States. However, carnitine can be a conditionally essential nutrient for several different types of individuals. Preterm infants require carnitine for life-sustaining metabolic processes but have a carnitine biosynthetic capability that is not fully developed. There is an increasing number of documented problems with carnitine metabolism in preterm infants not receiving an exogenous source of carnitine indicating that endogenous biosynthesis of carnitine is not adequate to meet the infant's need. Children with different forms of organic aciduria appear to have a greatly increased need for carnitine to function in the excretion of the accumulating organic acids. This need exceeds their dietary carnitine intake and carnitine biosynthetic capability. Renal patients treated with chronic hemodialysis appear to lose carnitine via the hemodialysis treatment, and this loss cannot be repleted simply by endogenous biosynthesis and dietary intake. Treatment with drugs such as valproic acid and metabolic stresses such as trauma, sepsis, organ failure, etc, can also result in a requirement for exogenous carnitine. Accurate assessment of the carnitine status of patients at risk for carnitine deficiency is fundamental to the identification of those patients who require carnitine as the result of altered metabolism. PMID:3088084

  20. The eukaryotic plasma membrane as a nutrient-sensing device.

    PubMed

    Holsbeeks, Inge; Lagatie, Ole; Van Nuland, An; Van de Velde, Sam; Thevelein, Johan M

    2004-10-01

    In eukaryotic cells, G-protein-coupled receptors (GPCRs), non-transporting nutrient carrier homologues and active nutrient carriers have been recently shown to function as sensors that directly monitor the level of nutrients in the extracellular environment. The plasma membrane is not only the cellular boundary at which signalling molecules that govern metabolism and proliferation are detected, but also the boundary across which nutrients that sustain the generation of energy and building blocks are transported. Nutrient sensors combine these functions in various ways. Classical receptor proteins detect the presence of nutrients, carriers combine the functions of nutrient transporters and receptors, and carrier homologues have lost their transport capacity and become pure receptors. The activation of signal transduction pathways by nutrients adds a new layer to the regulatory network that controls metabolism and proliferation. Nutrient sensors highlight the importance of both nutrients as signalling molecules and nutrient carriers as receptors for signalling pathways. PMID:15450611

  1. USDA Nutrient Database for Standard Reference

    MedlinePLUS

    ... site was jointly developed by the USDA Nutrient Data Laboratory, and the Food and Nutrition Information Center and Information Systems Division of the National Agricultural Library. Last Modified: Dec 7, 2011

  2. Nutrient deficiencies after gastric bypass surgery.

    PubMed

    Saltzman, Edward; Karl, J Philip

    2013-01-01

    Bariatric surgery, and in particular, gastric bypass, is an increasingly utilized and successful approach for long-term treatment of obesity and amelioration of comorbidities. Nutrient deficiencies after surgery are common and have multiple causes. Preoperative factors include obesity, which appears to be associated with risk for several nutrient deficiencies, and preoperative weight loss. Postoperatively, reduced food intake, suboptimal dietary quality, altered digestion and absorption, and nonadherence with supplementation regimens contribute to risk of deficiency. The most common clinically relevant micronutrient deficiencies after gastric bypass include thiamine, vitamin B??, vitamin D, iron, and copper. Reports of deficiencies of many other nutrients, some with severe clinical manifestations, are relatively sporadic. Diet and multivitamin use are unlikely to consistently prevent deficiency, thus supplementation with additional specific nutrients is often needed. Though optimal supplement regimens are not yet defined, most micronutrient deficiencies after gastric bypass currently can be prevented or treated by appropriate supplementation. PMID:23642197

  3. NUTRIENTS IN WATERSHEDS: DEVELOPING ENHANCED MODELING TOOLS

    EPA Science Inventory

    Nutrient enrichment is one of the most important stressors causing water-resource impairment. These impairments are causing devastating changes: 1) high nitrate concentrations have rendered the groundwaters and reservoirs in many regions impotable -- especially in the rural area...

  4. USDA NATIONAL NUTRIENT DATABASE FOR STANDARD REFERENCE

    EPA Science Inventory

    The USDA Nutrient Database for Standard Reference (SR) is the major source of food composition data in the United States. It provides the foundation for most food composition databases in the public and private sectors....

  5. NRMRL'S NUTRIENT-RELATED RISK MANAGEMENT RESEARCH

    EPA Science Inventory

    Anthropogenic loadings of nutrients into our Nation's atmosphere, aquatic, and terrestrial ecosystems have increased dramatically within the past few decades. Environmental impairments associated with this over fertilization include aquatic habitat loss due to low dissolved oxyge...

  6. Nutrient enrichment increases mortality of mangroves.

    PubMed

    Lovelock, Catherine E; Ball, Marilyn C; Martin, Katherine C; C Feller, Ilka

    2009-01-01

    Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients. PMID:19440554

  7. Prevalence of nutrient deficiencies in bariatric patients

    Microsoft Academic Search

    Seok Yee Toh; Nazy Zarshenas; John Jorgensen

    2009-01-01

    ObjectiveThe aims of this study were to determine the prevalence of nutrient deficiencies in patients who present for bariatric surgery, assess nutritional status after surgery, and compare these with preoperative levels.

  8. The use of nutrient audits to determine nutrient balances in Africa

    Microsoft Academic Search

    William F. Sheldrick; John Lingard

    2004-01-01

    A model, designed to carry out soil nutrient audits, has been used to calculate nutrient balances for Africa for the period 1961–1998 for land used for arable and permanent crops. The model indicates that in Africa and most African countries, nutrient depletion has been increasing and in 1998 was 3.5 million tonnes nitrogen (17.4 kg N ha?1 year?1). The corresponding

  9. The stoichiometry of particulate nutrients in Lake Tanganyika – implications for nutrient limitation of phytoplankton

    Microsoft Academic Search

    Marko Järvinen; Kalevi Salonen; Jouko Sarvala; Kristiina Vuorio; Anne Virtanen

    1999-01-01

    We studied the potential nutrient limitation of phytoplankton by means of seston nutrient stoichiometry and nutrient enrichment bioassays in the epilimnion of Lake Tanganyika. In most cases, the particulate carbon to phosphorus (C:P) ratio was high and indicated moderate P deficiency, while the respective C:N ratio mainly suggested moderate N deficiency. The N:P ratios of seston indicated rather balanced N

  10. The fate of nutrients in streams

    SciTech Connect

    Mulholland, P.

    1993-01-01

    In addition to important basic questions of ecological science, studies of streams and rivers contribute to an understanding of how to manage these systems to preserve or enhance their value as drinking water sources, recreation areas, and wildlife habitats. A factor that affects both ecological and human health is the concentration of various nutrients in streams. The research programs carried out at ORNL over the last few decades are briefly discussed along with current efforts on nutrient cycling in streams.

  11. Nutrient Requirements of the Cow and Calf. 

    E-print Network

    Maddox, L. A. Jr.

    1965-01-01

    the : devote little space to the neecls of the cow and energy value of feeds antl nutrient requirements of If'. Information necessary to establish require- animals (Glossary of Energy Terms, 1962) . A :nts for several functions are limited and some..., National Re- Osage County, Oklahoma, Texas A&M search Council Publication 464. Univ., PhD Dissertation. 10. Nutrient Requirements of Beef Cattle, 1963, 5. Fraps, G. S., 1947, The Composition and Util- National Academy of Science, National Re- ization...

  12. Nutrient elements in large Chinese estuaries

    Microsoft Academic Search

    Jing Zhang

    1996-01-01

    Based on comprehensive observations since 1983, this study summarizes major features of nutrient elements (nitrogen, phosphorus and silicon) in large Chinese river\\/estuary systems. Elevated nutrient element levels were observed in Chinese rivers, when compared to large and less disturbed aquatic systems (e.g. the Amazon, Zaire and Orinoco). Data from this study are similar to those obtained from the polluted and\\/or

  13. Nutrient shielding in clusters of cells

    NASA Astrophysics Data System (ADS)

    Lavrentovich, Maxim O.; Koschwanez, John H.; Nelson, David R.

    2013-06-01

    Cellular nutrient consumption is influenced by both the nutrient uptake kinetics of an individual cell and the cells' spatial arrangement. Large cell clusters or colonies have inhibited growth at the cluster's center due to the shielding of nutrients by the cells closer to the surface. We develop an effective medium theory that predicts a thickness ? of the outer shell of cells in the cluster that receives enough nutrient to grow. The cells are treated as partially absorbing identical spherical nutrient sinks, and we identify a dimensionless parameter ? that characterizes the absorption strength of each cell. The parameter ? can vary over many orders of magnitude among different cell types, ranging from bacteria and yeast to human tissue. The thickness ? decreases with increasing ?, increasing cell volume fraction ?, and decreasing ambient nutrient concentration ??. The theoretical results are compared with numerical simulations and experiments. In the latter studies, colonies of budding yeast, Saccharomyces cerevisiae, are grown on glucose media and imaged under a confocal microscope. We measure the growth inside the colonies via a fluorescent protein reporter and compare the experimental and theoretical results for the thickness ?.

  14. Contribution of Glomus intraradices inoculation to nutrient acquisition and mitigation of ionic imbalance in NaCl-stressed Trigonella foenum-graecum.

    PubMed

    Evelin, Heikham; Giri, Bhoopander; Kapoor, Rupam

    2012-04-01

    The study aimed to investigate the effects of an AM fungus (Glomus intraradices Schenck and Smith) on mineral acquisition in fenugreek (Trigonella foenum-graecum) plants under different levels of salinity. Mycorrhizal (M) and non-mycorrhizal (NM) fenugreek plants were subjected to four levels of NaCl salinity (0, 50, 100, and 200 mM NaCl). Plant tissues were analyzed for different mineral nutrients. Leaf senescence (chlorophyll concentration and membrane permeability) and lipid peroxidation were also assessed. Under salt stress, M plants showed better growth, lower leaf senescence, and decreased lipid peroxidation as compared to NM plants. Salt stress adversely affected root nodulation and uptake of NPK. This effect was attenuated in mycorrhizal plants. Presence of the AM fungus prevented excess uptake of Na(+) with increase in NaCl in the soil. It also imparted a regulatory effect on the translocation of Na(+) ions to shoots thereby maintaining lower Na(+) shoot:root ratios as compared to NM plants. Mycorrhizal colonization helped the host plant to overcome Na(+)-induced Ca(2+) and K(+) deficiencies. M plants maintained favorable K(+):Na(+), Ca(2+):Na(+), and Ca(2+):Mg(2+) ratios in their tissues. Concentrations of Cu, Fe, and Zn(2+) decreased with increase in intensity of salinity stress. However, at each NaCl level, M plants had higher concentration of Cu, Fe, Mn(2+), and Zn(2+) as compared to NM plants. M plants showed reduced electrolyte leakage in leaves as compared to NM plants. The study suggests that AM fungi contribute to alleviation of salt stress by mitigation of NaCl-induced ionic imbalance thus maintaining a favorable nutrient profile and integrity of the plasma membrane. PMID:21695577

  15. Growth, nutrient absorption, and moisture status of selected woody species in coal-mine spoil in response to an induced infection by the ectomycorrhizal fungus Pisolithus tinctorius

    SciTech Connect

    Walker, R.F.; West, D.C.; McLaughlin, S.B.

    1982-09-01

    In this study, nursery grown loblolly and Virginia pine seedlings infected with Pisolithus and control seedlings were outplanted on a coal mine spoil in Tennessee which had been previously hydroseeded. Granular fertilizer was applied by broadcasting to one-half of the seedlings of each ectomycorrhizal treatment at the rate of 112 kg/ha NPK. After 3 years, the survival and growth of loblolly pine infected with Pisolithus were superior to that of the control seedlings, and chemical analyses of foliar samples revealed that the seedlings with Pisolithus ectomycorrhizae had a higher foliar concentration of NO/sub 3/ and a lower concentration of Zn than the control seedlings. The survival, growth, and nutrient absorption of Virginia pine were not significantly affected by the infection with Pisolithus after 2 years, but both loblolly and Virginia pine seedlings with Pisolithus ectomycorrhizae exhibited an enhanced ability to absorb water during periods of high moisture stress, as determined by the pressure chamber technique. Fertilization substantially reduced the survival of the seedlings of both species. Sweet birch and European alder were grown under high, intermediate, and low fertility regimes in sand culture containing a mycelial inoculum of Pisolithus tinctorius for 5 months and then transplanted to coal mine spoil containing an identical Pisolithus inoculum. Control seedlings of each species were similarly grown except that no inoculum was incorporated into the potting media. The nutrient treatments initiated in the sand culture were continued throughout the study. Examinations of the roots of the sweet birch seedlings revealed that high fertility significantly reduced the development of Pisolithus ectomycorrhizae, but Pisolithus formed abundant ectomycorrhizae on the roots of sweet birch grown under the intermediate and low fertility regimes and these seedlings were significantly larger than comparable control seedlings.

  16. Version 3.0 January 2013 Nutrient Balance Sheet

    E-print Network

    Guiltinan, Mark

    Version 3.0 ­ January 2013 Nutrient Balance Sheet Prepared For Operator's Name Operator's Address for each crop management unit (if applicable) #12;Version 3.0 ­ January 2013 Nutrient Balance Sheet Summary = nutrient excess #12;Version 3.0 ­ January 2013 Nutrient Balance Sheet Summary Notes CMU/Field ID Crop Group

  17. Potential Effects of Nutrient Profiles on Nutrient Intakes in the Netherlands, Greece, Spain, USA, Israel, China and South-Africa

    Microsoft Academic Search

    Annet J. C. Roodenburg; Anke Schlatmann; Mariska Dötsch-Klerk; Robert Daamen; Jie Dong; Marta Guarro; Margarita Stergiou; Nazeeia Sayed; Eunice Ronoh; Léon Jansen; Jacob C. Seidell; Daniel Tomé

    2011-01-01

    IntroductionNutrient profiling is defined as the science of categorising foods based on their nutrient composition. The Choices Programme is a nutrient profile system with criteria that determine whether foods are eligible to carry a “healthier option” stamp. The Daily Menu Method which has been developed to evaluate these criteria is described here. This method simulates the change in calculated nutrient

  18. Are nutrient databases and nutrient analysis systems ready for the International implications of nutrigenomics?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective is to discuss the implications internationally of the increased focus on nutrigenomics as the underlying basis for individualized health promotion and chronic disease prevention and the challenges presented to existing nutrient database and nutrient analysis systems by these trends. De...

  19. Nutrient-plankton interaction with a toxin in a variable input nutrient environment

    E-print Network

    Baglama, James

    -0816 Abstract. A simple model of phytoplankton-zooplankton interaction with a periodic input nutrient and dinoflagellates, although many other groups of algae are also very populated. Pollution of freshwater and marine of toxic substances upon nutrient- phytoplankton-zooplankton interaction. In the early 1980s, Hansen

  20. South CarolinaSouth Carolina Nutrient Management Rules,Nutrient Management Rules,

    E-print Network

    Confined Animals Approx. 1,100 total confined animal facilities 153 large CAFO's 121 poultry 31 swine 1 dairy 566 medium CAFO's 85% poultry 8% swine 6% dairy #12;Swine Beef Dairy Broiler Turkey Layer Manure ProductionManure Production Poultry ­ 40% Cow ­ 48% Swine ­ 12% #12;Nutrient Management ofNutrient Management of Confined

  1. Louisiana's Nutrient ManagementLouisiana's Nutrient Management Educational/Research ProgramsEducational/Research Programs

    E-print Network

    Louisiana's Nutrient ManagementLouisiana's Nutrient Management Educational/Research ProgramsEducational/Research Programs Matthew F. Stephens Area Agent Calhoun, La. #12;Louisiana Facts Poultry production is largest #12;Louisiana Facts Cotton .....491,000 acres Rice.....530,000 acres Soybeans....770,000 acres Grain

  2. Modeling the Response of Nutrient Concentrations and Primary Productivity in Lake Michigan to Nutrient Loading Scenarios

    EPA Science Inventory

    A water quality model, LM3 Eutro, will be used to estimate the response of nutrient concentrations and primary productivity in Lake Michigan to nutrient loading scenarios. This work is part of a larger effort, the Future Midwestern landscapes study, that will estimate the produc...

  3. Engaging Citizens to Urban Nutrient Planning of Lawns within a Nutrient Sensitive Watershed

    Microsoft Academic Search

    Steven G. Hefner; Clay Robertson

    Simple and concise urban lawn nutrient management plans can be successfully implemented to combat eutrophication of lakes and streams. Soil test values from 540 lawns near Springfield, Missouri found that 51% of the samples tested above optimum levels for available phosphorus, especially where lawns were more than 20 years old. Urban nutrient management plans that contain the type, quantity, and

  4. Nutrient Requirements of Domestic Animals, Number 10: Nutrient Requirements of Laboratory Animals. Third Revised Edition, 1978.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Board on Agricultural and Renewable Resources.

    This report deals with the nutrient requirements of seven species of animals used extensively for biomedical research in the United States. Following an introductory chapter of general information on nutrition, chapters are presented on the nutrient requirements of the laboratory rat, mouse, gerbil, guinea pig, hamster, vole, and fishes. Each…

  5. WATER NUTRIENTS, PLANT NUTRIENTS, AND INDICATORS OF BIOLOGICAL CONTROL ON WATERHYACINTH AT TEXAS FIELD SITES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Waterhyacinth (Eichhornia crassipes (Mart.) Solms) can take up water nutrients sufficient for growth under highly variable conditions. Few studies have linked water and plant nutrients to measures of biological control in field populations. Fifteen sites in coastal Texas were sampled in 2003 and 2...

  6. Effects of earthworm casts and compost on soil microbial activity and plant nutrient availability

    Microsoft Academic Search

    Hala I Chaoui; Larry M Zibilske; Tsutomu Ohno

    2003-01-01

    Vermicomposting differs from conventional composting because the organic material is processed by the digestive systems of worms. The egested casts can be used to improve the fertility and physical characteristics of soil and potting media. In this study, the effects of earthworm casts (EW), conventional compost (CP) and NPK inorganic fertilizer (FT) amendments on N mineralization rates, microbial respiration, and

  7. Exergy analysis of nutrient recovery processes.

    PubMed

    Hellström, D

    2003-01-01

    In an exergy analysis, the actual consumption of resources in physical and chemical processes is calculated. Energy and chemical elements are not consumed in the processes--they are only transformed into other forms with lower quality. The principals of exergy analysis are illustrated by comparing different wastewater treatment systems for nutrient recovery. One system represents an end-of-pipe structure, whereas other systems include source separation of grey water, black water, and urine. The exergy flows analysed in this paper are those related to management and treatment of organic matter and nutrients. The study shows that the total exergy consumption is lowest for the system with source separation of urine and faeces and greatest for the conventional wastewater treatment system complemented by processes for nutrient recovery. PMID:12926618

  8. Efect of organic barley-based crop rotations on soil nutrient balance in a semiarid environment for a 16-year experiment

    NASA Astrophysics Data System (ADS)

    Meco, Ramón; María Moreno, Marta; Lacasta, Carlos; Moreno, Carmen

    2013-04-01

    In natural ecosystems with no percolating moisture regime, the biogeochemical cycle can be considered a closed system because the nutrients extracted by the roots will be returned to the soil after a certain time. In organic farming, a cycle model as close as possible is taken as a guideline, but we have to consider that unlike natural ecosystems, where most of the nutrients remain in the cycle, the agrosystems are open cycles. To achieve a sustainable fertility of the soil, the soil nutrient levels, the extractions according to the expected crop yields and the export refunds in the form of crop residues, biological nitrogen fixation, green manure or compost will have to be determined. Nutrient balance should be closed with external inputs, always avoiding to be a source of negative impacts on the environment. In organic farming without exogenous inputs, the effect of the crop rotations is much more noticeable in the nutrient balance than in the conventional farming fields which every year receive inputs of nutrients (nitrogen, phosphorus and potassium) in the form of chemical fertilizers. The most extractive crop rotations are those that produce a greater decrease in soil reserves, and in these cases exogenous inputs to maintain sustainability should be considered; however, in less extractive crop rotations, extractions can be restored by the edaphogenesis processes. In this work, soil organic matter, phosphorus and potassium balances were analyzed in different organic barley-based crop rotations (barley monoculture [b-b] and in rotation with vetch for hay production [B-Vh], vetch as green manure [B-Vm], sunflower [B-S], chickpea [B-C] and fallow [B-F]) in clay soils under a semiarid environment ("La Higueruela" Experimental Farm, Santa Olalla, Toledo, central Spain) over a 16 year period. Additionally, barley monoculture in conventional farming [B-B] was included. In the organic system, the fertilization involved the barley straw in all rotations, the sunflower straw in B-S, the symbiotic nitrogen from the vetch crops and the green manure in B-Vm. In the conventional system, fertilization consisted on barley straw and chemical fertilizers at a rate of 80-60-30 kg N-P-K ha-1. Before the organic management, the whole plot was subjected to conventional practices. The highest total yields (and therefore the nutrients extractions) were obtained in B-Vh, followed in this order by B-B, B-S, B-F, B-Vm, B-C and b-b. The crop rotations with the highest yields favoured the microbial activity and the organic residues mineralization, although this caused, eventually, a small decrease in the soil organic matter content. Since the eighth year, this parameter remained more stable until the end of the study period. The highest decrease of soil organic matter took place in B-F and B-S, while the lowest ones happened in B-B, where the great amounts of barley straw incorporated into the soil compensated the organic matter losses. The conversion from conventional to organic management with the incorporation of the straw to the soil implies a re-adaptation process with a decrease of the soil phosphorus level by the increasing soil microbial biomass. A decrease of phosphorus during the first six years of the experiment and a posterior recovery and stabilization of this ratio by the solubilisation of the fixed phosphorus was observed. B-F and B-S presented the lowest soluble phosphorus losses, while B-C the highest ones. In the same way, the potassium level decreased during the first eight years and after that remained constant. The highest decreases took place in the rotations with the biggest amounts of barley straw; this decrease could be explained by the nutrient immobilization caused by the microbial biomass.

  9. Export of nutrients from the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Torres-Valdés, Sinhué; Tsubouchi, Takamasa; Bacon, Sheldon; Naveira-Garabato, Alberto C.; Sanders, Richards; McLaughlin, Fiona A.; Petrie, Brian; Kattner, Gerhard; Azetsu-Scott, Kumiko; Whitledge, Terry E.

    2013-04-01

    study provides the first physically based mass-balanced transport estimates of dissolved inorganic nutrients (nitrate, phosphate, and silicate) for the Arctic Ocean. Using an inverse model-generated velocity field in combination with a quasi-synoptic assemblage of hydrographic and hydrochemical data, we quantify nutrient transports across the main Arctic Ocean gateways: Davis Strait, Fram Strait, the Barents Sea Opening (BSO), and Bering Strait. We found that the major exports of all three nutrients occur via Davis Strait. Transports associated with the East Greenland Current are almost balanced by transports associated with the West Spitsbergen Current. The most important imports of nitrate and phosphate to the Arctic occur via the BSO, and the most important import of silicate occurs via Bering Strait. Oceanic budgets show that statistically robust net silicate and phosphate exports exist, while the net nitrate flux is zero, within the uncertainty limits. The Arctic Ocean is a net exporter of silicate (-15.7 ± 3.2 kmol s-1) and phosphate (-1.0 ± 0.3 kmol s-1; net ± 1 standard error) to the North Atlantic. The export of excess phosphate (relative to nitrate) from the Arctic, calculated at -1.1 ± 0.3 kmol s-1, is almost twice as large as previously estimated. Net transports of silicate and phosphate from the Arctic Ocean provide 12% and 90%, respectively, of the net southward fluxes estimated at 47°N in the North Atlantic. Additional sources of nutrients that may offset nutrient imbalances are explored, and the relevance and the pathway of nutrient transports to the North Atlantic are discussed.

  10. Mapping Nutrients Crucial to a Growing Population

    NASA Astrophysics Data System (ADS)

    Tarnowski, J. R.; Cassidy, E. S.; Gerber, J. S.

    2011-12-01

    Over two billion people worldwide suffer from inadequate levels of micronutrients, mainly in the form of iodine, iron, and vitamin A deficiencies. With a growing population, producing crops that contain high amounts of these micronutrients is of increased importance. Addressing these deficiencies sustainably requires a detailed examination of the agricultural production of the micronutrients. The purpose of this study is to determine whether or not enough of these important nutrients are produced to meet the nutritional needs of the global population, and to determine where nutrients are most deficient. We used area specific crop production data to map where and how much iron and vitamin A are produced from major crops.

  11. Fast Detection of Nutrient Limitation in Macroalgae and Seagrass with Nutrient-Induced Fluorescence

    PubMed Central

    den Haan, Joost; Huisman, Jef; Dekker, Friso; ten Brinke, Jacomina L.; Ford, Amanda K.; van Ooijen, Jan; van Duyl, Fleur C.; Vermeij, Mark J. A.; Visser, Petra M.

    2013-01-01

    Background Rapid determination of which nutrients limit the primary production of macroalgae and seagrasses is vital for understanding the impacts of eutrophication on marine and freshwater ecosystems. However, current methods to assess nutrient limitation are often cumbersome and time consuming. For phytoplankton, a rapid method has been described based on short-term changes in chlorophyll fluorescence upon nutrient addition, also known as Nutrient-Induced Fluorescence Transients (NIFTs). Thus far, though, the NIFT technique was not well suited for macroalgae and seagrasses. Methodology & Principal Findings We developed a new experimental setup so that the NIFT technique can be used to assess nutrient limitation of benthic macroalgae and seagrasses. We first tested the applicability of the technique on sea lettuce (Ulva lactuca) cultured in the laboratory on nutrient-enriched medium without either nitrogen or phosphorus. Addition of the limiting nutrient resulted in a characteristic change in the fluorescence signal, whereas addition of non-limiting nutrients did not yield a response. Next, we applied the NIFT technique to field samples of the encrusting fan-leaf alga Lobophora variegata, one of the key algal species often involved in the degradation of coral reef ecosystems. The results pointed at co-limitation of L. variegata by phosphorus and nitrogen, although it responded more strongly to phosphate than to nitrate and ammonium addition. For turtle grass (Thalassia testudinum) we found the opposite result, with a stronger NIFT response to nitrate and ammonium than to phosphate. Conclusions & Significance Our extension of the NIFT technique offers an easy and fast method (30–60 min per sample) to determine nutrient limitation of macroalgae and seagrasses. We successfully applied this technique to macroalgae on coral reef ecosystems and to seagrass in a tropical inner bay, and foresee wider application to other aquatic plants, and to other marine and freshwater ecosystems. PMID:23861947

  12. MIDDLE SNAKE RIVER PRODUCTIVITY AND NUTRIENT ASSESSMENT

    EPA Science Inventory

    From 1992 to 1994, the University of Idaho conducted a research project on the water quality- limited section of the MIddle Snake River from Twin Falls downstream to Upper Salmon Falls Dam in an effort to determine the relationship between the nutrients and sediments entering thi...

  13. Pesticide and Nutrient Management for Orchards

    E-print Network

    Pesticide and Nutrient Management for Orchards FAS 104 · October 2001 MICHIGAN STATE U N I V E R S I T Y EXTENSION Michigan Groundwater Stewardship Program Traditionally, pesticides and fertilizers is concerned about the possibility of agricultural pesticides and fertilizers showing up in water samples taken

  14. Biological Nutrient Removal in Compact Biofilm Systems

    Microsoft Academic Search

    J. P. Bassin

    2012-01-01

    The removal of nutrients such as nitrogen and phosphorus from both domestic and industrial wastewaters is imperative since they potentially harm the environment. One of the main consequences of excessive availability of nitrogen and phosphorus in aquatic ecosystems (freshwater, marine and estuarine) is the overgrowth of algae and other aquatic plants, a phenomenon designated as eutrophication. Algae and aquatic plants

  15. The nutrient cycling model: lessons learned

    Microsoft Academic Search

    Dale W Johnson; Trine Sogn; Sheila Kvindesland

    2000-01-01

    The nutrient cycling model (NuCM) is a stand level model that depicts the cycling of N, P, K, Ca, Mg, and S on daily, weekly or monthly time scales. NuCM has been applied to several forest ecosystems (ponderosa pine, red spruce, beech, eastern deciduous, loblolly pine, slash pine, Scots pine, and Norway spruce) to simulate the effects of changing atmospheric

  16. Nutrient Estimation Using Subsurface Sensing Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report investigates the use of precision management techniques for measuring soil conductivity on feedlot surfaces to estimate nutrient value for crop production. An electromagnetic induction soil conductivity meter was used to collect apparent soil electrical conductivity (ECa) from feedlot p...

  17. Nutrient Management Module No. 12 Water Quality

    E-print Network

    Lawrence, Rick L.

    . Eutrophication The U.S. Environmental Protection Agency (EPA) has identified eutrophication as the main cause of impaired surface water quality (USEPA, 1999). Eutrophication is a process characterized by high nutrient et al., 2000). The process of eutrophication may negatively impact water use for recreation, industry

  18. NUTRIENT MEDIATED PROTECTION AGAINST ENDOTHELIAL CELL DYSFUNCTION

    Microsoft Academic Search

    Gudrun Reiterer

    2004-01-01

    Atherosclerosis is thought to be initiated by endothelial cell dysfunction. Research described in this dissertation is focused on interactions of nutrients, cytokines and pharmaceutical compounds in the intracellular signaling pathways leading to endothelial cell activation. The flavonoid quercetin could significantly downregulate the inflammatory pathways induced by linoleic acid as determined by DNA binding assays of the proinflammatory transcription factors nuclear

  19. Nutrient management studies in biofuel cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research was conducted to determine the effect of nutrient management practices on biofuel crop production, and to evaluate long term effects of biofuel crop production on selected chemical, physical and microbiological properties. Experimental plots for research on biofuel crop production were esta...

  20. OBESITY AND NUTRIENT CONSUMPTION: A RATIONAL ADDICTION?

    Microsoft Academic Search

    TIMOTHY J. RICHARDS; PAUL M. PATTERSON; ABEBAYEHU TEGENE

    2007-01-01

    Recent research shows that the dramatic rise in obesity in the United States is due more to the overconsumption of unhealthy foods than underactivity. This study tests for an addiction to food nutrients as a potential explanation for the apparent excessive consumption. A random coefficients (mixed) logit model is used to test a multivariate rational addiction model. The results reveal

  1. DETECTING TEMPORAL CHANGE IN WATERSHED NUTRIENT YIELDS

    EPA Science Inventory

    Meta-analyses reveal that nutrient yields tend to be higher for watersheds dominated by anthropogenic uses (e.g., urban, agriculture) and lower for watersheds dominated by natural vegetation. One implication of this pattern is that loss of natural vegetation will produce increase...

  2. Nutrient Management Module No. 4 Phosphorus Cycling,

    E-print Network

    Lawrence, Rick L.

    Nutrient Management Module No. 4 Phosphorus Cycling, Testing and Fertilizer Recommendations about phosphorus. Objectives 1.Understand the various soil forms of phosphorus 2.Recognize how soil and climate properties affect phosphorus cycling in soil 3.Recognize how cropping systems affect phosphorus

  3. Real sea experiment of ocean nutrient enhancer \\

    Microsoft Academic Search

    K. Ouchi; A. J. Murphy

    2003-01-01

    The five years project of increasing a primary production and making a new fishing ground by upwelling deep ocean water (DOW) which is very rich in nutrient salt such as Nitrogen, Phosphorus, etc. was commenced in the year of 2000, sponsored by the Fisheries Agency of Japanese Government and Marino-Forum 21. In the open ocean, now, there are no successful

  4. SOUTHEASTERN PLAINS NUTRIENT RESPONSE (SPNR) PROJECT

    EPA Science Inventory

    This study is part of a multi-year effort to examine nutrient biological responses and to develop accurate tools for measuring and assessing those responses. For 2007, this work involves developing a methodology for sampling and analysis of periphyton from sand and sediment. We...

  5. Original article Digestibility, blood levels of nutrients

    E-print Network

    Paris-Sud XI, Université de

    Original article Digestibility, blood levels of nutrients and skin responses of calves fed soyabean 24 August 1994) Summary ― Three milk substitute diets in which the protein was provided either by skim milk only (con- trol diet) or mainly (71%) by a commercial soyabean or lupin concentrate (soyabean

  6. NUTRIENT RESPONSE IN GREAT LAKES WETLANDS

    EPA Science Inventory

    The U.S. EPA National Health and Environmental Effects Laboratory's Aquatic Stressor Framework and associated Nutrient Implementation Plan define scientific and regulatory needs, and lay-out research goals too for a cross divisional program to investigate stressor-response relati...

  7. Effects of Nutrients on Spring Ecosystems

    Microsoft Academic Search

    Robert L. Knight; Sky K. Notestein

    Summary The relationship between nutrients and spring ecosystem structure and function primarily focuses on the state-wide increase in spring nitrate concentrations derived from anthropogenic sources and the concurrent observed visual decline of these ecosystems. However, the apparent correlation between increased nitrate loading and declining aesthetic appearance of spring ecosystems has only anecdotally provided evidence for a causative relationship. Organism-level studies,

  8. AGRICIJLTURAL NUTRIENT MANAGEMENT LOWER FRASER VALLEY

    E-print Network

    , Surface Water and Groundwater Factors 11 4.0 1991 AGRICULTURAL WASTE MANAGEMENT PRACTICES 15 4.1 Dairy 15 OF AGRICULTURAL WASTES in the LOWER FRASER VALLEY Project 3 AGRICULTURAL NUTRIENT MANAGEMENT in the LOWER FRASER 71 9.0 SUMMARY 78 REFERENCES 80 #12;iii List of Figures 1.0 Agricultural Waste Management Zones 3 2

  9. Ocean nutrient ratios governed by plankton biogeography.

    PubMed

    Weber, Thomas S; Deutsch, Curtis

    2010-09-30

    The major nutrients nitrate and phosphate have one of the strongest correlations in the sea, with a slope similar to the average nitrogen (N) to phosphorus (P) content of plankton biomass (N/P = 16:1). The processes through which this global relationship emerges despite the wide range of N/P ratios at the organism level are not known. Here we use an ocean circulation model and observed nutrient distributions to show that the N/P ratio of biological nutrient removal varies across latitude in Southern Ocean surface waters, from 12:1 in the polar ocean to 20:1 in the sub-Antarctic zone. These variations are governed by regional differences in the species composition of the plankton community. The covariation of dissolved nitrate and phosphate is maintained by ocean circulation, which mixes the shallow subsurface nutrients between distinct biogeographic provinces. Climate-driven shifts in these marine biomes may alter the mean N/P ratio and the associated carbon export by Southern Ocean ecosystems. PMID:20882009

  10. Agronomy Facts 38-D A Nutrient Management

    E-print Network

    Kaye, Jason P.

    assessment, and management option selection for the next plan. This process is facilitated by the appropriate stage of the process (Figure 2, next page). For instance, input information, such as manure analyses is part of the nutrient management approach described in this series. Any part of the process

  11. Duodenal luminal chemosensing; acid, ATP, and nutrients.

    PubMed

    Akiba, Yasutada; Kaunitz, Jonathan D

    2014-01-01

    Intestinal chemosensing of endogenous and exogenous luminal compounds, including acid, CO2, bile acids and nutrients is an emerging area of gastrointestinal research, since gut hormones, particularly including incretins and glucagon-like peptide-2 (GLP-2) are released in response to luminal nutrients. Identification of luminal chemosensors such as nutrient-ligand G-protein coupled receptors (GPCRs) in enteroendocrine cells has linked luminal compounds to the corresponding gut hormone release. Mucosal chemical sensors are necessary to exert physiological responses such as secretion, digestion, absorption, and motility. We have been studying the mechanisms by which luminal compounds are sensed via mucosal acid sensors and GPCRs, which trigger mucosal defense mechanisms. In addition to luminal acid/CO2 sensing in the duodenum, recent studies also show that compounds present post-prandially such as amino acids, bile acids and fatty acids, enhance duodenal mucosal defenses, with digestion following the initial gastric processing. These studies may form the basis for therapies in which luminal nutrients release gut hormones that affect the mucosal protection, appetite, satiety, and systemic metabolisms. PMID:23886391

  12. CH4 emissions from two floodplain fens of differing nutrient status

    NASA Astrophysics Data System (ADS)

    Stanley, Kieran; Heppell, Catherine; Belyea, Lisa; Baird, Andrew

    2014-05-01

    Floodplain fens emit large amounts of CH4 in comparison with ombrotrophic bogs. Little is known about the effect of fluvial nitrogen (N) and phosphorus (P) on CH4 dynamics in fens, although N and P affect carbon (C) dynamics indirectly in other environments by controlling plant growth and root exudate release, as well as by altering microbial biomass and decomposition rates. This study aimed to compare CH4 emissions from two floodplain fen sites which differ in nutrient status, Sutton Fen (52°45'N 001°30'E) and Strumpshaw Fen (52°36'N 001°27'E), in the Norfolk Broadland of England. Sutton and Strumpshaw Fen are under conservation management and both sites have water levels that vary within a few decimetres above and below the surface. The sites are dominated by reed (Phragmites australis). Areas within the fens where the reed was cut in 2009 were chosen for this study. Average plant height and mean aboveground biomass were significantly greater at Strumpshaw (107.2 ± 7.8 cm and 1578 ± 169 g m-2, respectively) than Sutton (56.5 ± 5.1 cm and 435 ± 42 g m-2) as were mean foliar N and P contents (21.8 ± 1.5 g kg-1 and 2.0 ± 0.2 g kg-1 at Strumpshaw, versus 16.3 ± 1.5 g kg-1 and 1.1 ± 0.1 g kg-1 at Sutton). Foliar NPK ratios showed Strumpshaw to be N limited, whereas Sutton was both N and P limited, depending on microsite. Surface peat N and P contents were also greater at Strumpshaw (28.3 ± 0.35 g kg-1 and 0.78 ± 0.02 g kg-1, respectively) than Sutton (18.32 ± 0.87 g kg-1 and 0.43 ± 0.1 g kg-1). These results indicate clear differences in nutrient status between the two sites despite their geographical proximity and other similarities. CH4 emissions were monitored monthly between 19th June 2012 and 2nd September 2013 using tall static chambers and glass funnel-traps, the latter for ebullition. Steady fluxes did not follow a clear seasonal pattern; however, emission was greatest in the summer months. Strumpshaw had a greater range in efflux (0.25 to 134.2 mg CH4 m-2 h-1) than Sutton (0.17 to 29.82 mg CH4 m-2 h-1). Ebullition was generally greater at Sutton throughout the study period, with rates ranging from 0 to 62.09 mg CH4 m-2 h-1 and 0 to 19.30 mg CH4 m-2 h-1 for Sutton and Strumpshaw, respectively. Fluxes were generally within the range of values reported in the literature for ebullition (0 to 466 mg CH4 m-2 h-1) and steady fluxes (0 to 76.83 mg CH4 m-2 h-1). Results show the importance of floodplain fens for CH4 emission, and more research needs to be undertaken to fully understand the factors controlling CH4 fluxes from these systems.

  13. OXYGEN UPTAKE AND NUTRIENT REGENERATION IN THE PECONIC ESTUARY

    EPA Science Inventory

    EXECUTIVE SUMMARY: OXYGEN UPTAKE AND NUTRIENT REGENERATION IN THE PECONIC ESTUARY Rates of oxygen consumption and nutrient regeneration were measured annually throughout the Peconic Estuarine System. Sediment and water column oxygen uptake were measured to determine the potential...

  14. NUTRIENT DYNAMICS IN RELATION TO GEOMORPHOLOGY OF RIVERINE WETLANDS

    EPA Science Inventory

    Variation in water depth and soil properties associated with geomorphic structures can affect riverine wetland nutrient dynamics by altering biogeochemical processes. We examined the seasonal influence of soils and geomorphology on nutrient forms and concentrations in riverine we...

  15. Comparison of Nutrient Drivers and Response Metrics in Oregon Estuaries

    EPA Science Inventory

    With the goal of assessing sensitivity to nutrient enrichment, we present a cross-estuary comparison of nutrient sources, levels, and biological responses (phytoplankton and macroalgae) for thirteen Oregon estuaries. Nitrogen levels in the upstream portions of the estuaries are ...

  16. ENHANCED NUTRIENT REMOVAL FROM ON-SITE WASTEWATER TREATMENT SYSTEMS

    EPA Science Inventory

    Nutrient (nitrogen and phosphorus) runoffs impact streams and ecosystems. Furthermore, on-site wastewater treatment systems are important sources of nutrient discharges because effluents from septic tanks typically contain high concentrations of organic matter, nitrogen and ph...

  17. WATER NUTRIENTS, PLANT NUTRIENTS, AND INDICATORS OF BIOLOGICAL CONTROL IN WATERHYACINTH AT TEXAS FIELD SITES.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interactions occur under controlled conditions between the nutrient content of floating waterhyacinth plants (Eichhornia crassipes) and reporduction of waterhyacinth weevils (Neochetina bruchi and N. eichhorniae) introduced for biocontrol. Few studies have linked water nutrition, plant nutrition, a...

  18. Nutrient-substituted hydroxyapatites: synthesis and characterization

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.

    1999-01-01

    Incorporation of Mg, S, and plant-essential micronutrients into the structure of synthetic hydroxyapatite (HA) may be advantageous for closed-loop systems, such as will be required on Lunar and Martian outposts, because these apatites can be used as slow-release fertilizers. Our objective was to synthesize HA with Ca, P, Mg, S, Fe, Cu, Mn, Zn, Mo, B, and Cl incorporated into the structure, i.e., nutrient-substituted apatites. Hydroxyapatite, carbonate hydroxyapatite (CHA), nutrient-substituted hydroxyapatite (NHA), and nutrient-substituted carbonate hydroxyapatite (NCHA) were synthesized by precipitating from solution. Chemical and mineralogical analysis of precipitated samples indicated a considerable fraction of the added cations were incorporated into HA, without mineral impurities. Particle size of the HA was in the 1 to 40 nm range, and decreased with increased substitution of nutrient elements. The particle shape of HA was elongated in the c-direction in unsubstituted HA and NHA but more spherical in CHA and NCHA. The substitution of cations and anions in the HA structure was confirmed by the decrease of the d[002] spacing of HA with substitution of ions with an ionic radius less than that of Ca or P. The DTPA-extractable Cu ranged from 8 to 8429 mg kg-1, Zn ranged from 57 to 1279 mg kg-1, Fe from 211 to 2573 mg kg-1, and Mn from 190 to 1719 mg kg-1, depending on the substitution level of each element in HA. Nutrient-substituted HA has the potential to be used as a slow-release fertilizer to supply micronutrients, S, and Mg in addition to Ca and P.

  19. Dairy manure nutrient analysis using quick tests.

    PubMed

    Singh, A; Bicudo, J R

    2005-05-01

    Rapid on-farm assessment of manure nutrient content can be achieved with the use of quick tests. These tests can be used to indirectly measure the nutrient content in animal slurries immediately before manure is applied on agricultural fields. The objective of this study was to assess the reliability of hydrometers, electrical conductivity meter and pens, and Agros N meter against standard laboratory methods. Manure samples were collected from 34 dairy farms in the Mammoth Cave area in central Kentucky. Regression equations were developed for combined and individual counties located In the area (Barren, Hart and Monroe). Our results indicated that accuracy in nutrient estimation could be improved if separate linear regressions were developed for farms with similar facilities in a county. Direct hydrometer estimates of total nitrogen were among the most accurate when separate regression equations were developed for each county (R2 = 0.61, 0.93, and 0.74 for Barren, Hart and Monroe county, respectively). Reasonably accurate estimates (R2 > 0.70) were also obtained for total nitrogen and total phosphorus using hydrometers, either by relating specific gravity to nutrient content or to total solids content. Estimation of ammoniacal nitrogen with Agros N meter and electrical conductivity meter/pens correlated well with standard laboratory determinations, especially while using the individual data sets from Hart County (R2 = 0.70 to 0.87). This study indicates that the use of quick test calibration equations developed for a small area or region where farms are similar in terms of manure handling and management, housing, and feed ration are more appropriate than using "universal" equations usually developed with combined data sets. Accuracy is expected to improve if individual farms develop their own calibration curves. Nevertheless, we suggest confidence intervals always be specified for nutrients estimated through quick testing for any specific region, county, or farm. PMID:15974265

  20. Global nutrients data synthesis based on Reference Material of Nutrients of Seawater

    NASA Astrophysics Data System (ADS)

    Aoyama, Michio; Murata, Akihiko; Nishino, Shigeto

    2013-04-01

    Realistic distributions of nitrate, phosphate and silicate and inventories of them in the world's ocean are basic issues of geochemical study of nitrogen, phosphorous and silicon cycles as well as tracer use of nutrients for deep ocean circulation. WOA09 and WGHC were global hydrographic datasets created by objective analysis and offset correction/objective analysis, respectively. However synthesis using mathematics methods and experience could get apparent global comparability but does not have a firm foundation, therefore accuracy is unknown for nutrients data in WOA05/09 and WGHC. Recently hydrographic dataset such as CARINA and PACIFICA were also created by synthesis. We did global synthesis work based on Reference Material of Nutrients in Seawater (RMNS) for WOCE/CLIVAR cruises datasets, WGHC datasets and some new hydrographic cruises which cover the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean and the Arctic Ocean. Among 69982 profiles in 5174 cruises, we could put correction factors of nutrients concentration for 14491 profiles in 268 cruises for nitrate, 18378 profiles in 412 cruises for phosphate and 15825 profiles in 268 cruises for silicate. Global Nutrients Dataset 2010, GND10, is newly created as 0.5 deg. × 0.5 deg. and 50 m interval of 138 levels gridded dataset based on corrected nutrients profiles described above. One feature of GND10 is that nitrate vs. phosphate ratio in deep waters in WOA dataset showed a peak at 14.6 while nitrate vs. phosphate ratio in GND10 showed a peak at 14.3 and kurtosis of frequency distribution of nitrate vs. phosphate ratio is larger in GND10 dataset rather than that in WOA dataset. A reason of larger kurtosis of distribution of nitrate vs. phosphate ratio might be that comparability of nitrate and phosphate concentration data was improved. Newly created GND10 can provide more realistic distribution of nutrients in the world ocean because comparability of nutrients concentration in GND10 is improved based on RMNS. The GND10 would be useful to study changes in the distribution of concentrations of nutrients in the world ocean and also useful as new initial conditions for modelers who studies global changes. Carbonate system data and oxygen data will be merged with factor corrected nutrients data to study coupling of carbonate system and nutrients cycles, too.

  1. November 2006 Issue #2 2006 TILLAGE EFFECTS ON NUTRIENT STRATIFICATION

    E-print Network

    Balser, Teri C.

    ____________________________________________________________________________________ TILLAGE EFFECTS ON NUTRIENT STRATIFICATION AND SOIL TEST RECOMMENDATIONS Dick Wolkowski 1/ Soil testing. Because P, K, and to some extent soil pH are immobile in soils nutrient and pH stratification will develop cause more variability in fertilizer recommendations due to nutrient stratification than might be found

  2. Environmental effects on nutrient and energy metabolism in pigs

    Microsoft Academic Search

    C. Wenk

    1998-01-01

    Besides the genetic predisposition and the dietary supply of nutrients, environmental factors affect the performance of the pig. Environment can affect the nutrient composition and availability of the feed. It can also influence appetite and therefore the feed intake. Furthermore, nutrient and energy utilization on the level of digestion and intermediate metabolism can depend on environmental factors. Especially the energy

  3. ENHANCED USE OF FEED AND MANURE NUTRIENTS IN ANIMAL AGRICULTURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole-farm nutrient balances and animal:cropland ratios are used to asses overall pollution risks of livestock farms. These whole-farm indicators cannot address, however, how nutrient management in one production component (e.g., feed) may affect nutrient cycling in other production components (e.g...

  4. Land Cover - Nutrient Export Relationships in Space and Time

    EPA Science Inventory

    The relationship between watershed land-cover composition and nutrient export has been well established through several meta-analyses. The meta-analyses reveal that nutrient loads from watersheds dominated by natural vegetation tend to be lower than nutrient loads from watershed...

  5. Nutrient Cycling in a Natural Stand of Typha angustifolia

    Microsoft Academic Search

    Pratima Sharma; Takashi Asaeda; Jagath Manatunge; Takeshi Fujino

    2006-01-01

    We studied nutrient cycling within a natural monospecific stand of Typha angustifolia along the shoreline of Lake Teganuma, a shallow eutrophic lake northeast of Tokyo. Seasonal patterns of biomass and nutrient concentrations in the above- and belowground plant parts were observed over a period of two years, and nutrients released from the dead plants into the water environment were estimated

  6. Nutrient Input into the Caspian Sea with River Runoff

    Microsoft Academic Search

    A. V. Leonov; N. A. Nazarov

    2001-01-01

    Long-term observational data are used to compare and analyze time and space variations in the concentrations of nutrients in the water of major rivers flowing into the Caspian Sea and assess the nutrients runoff into the sea. Annual variations in the normal monthly values of river runoff and nutrient compound concentrations and input into the sea are considered (18 compounds

  7. Posidonia oceanica meadow: a low nutrient high chlorophyll (LNHC) system?

    PubMed Central

    Gobert, Sylvie; Laumont, Noémie; Bouquegneau, Jean-Marie

    2002-01-01

    Background In spite of very low nutrient concentrations in its vicinity – both column and pore waters-, the Posidonia oceanica of the Revellata Bay displays high biomass and productivity. We measured the nutrient fluxes from the sediment into the water enclosed among the leaf shoots ("canopy water") to determine if it is possible source of nutrients for P. oceanica leaves. Results During the summer, the canopy water appears to act as a nutrient reservoir for the plant. During that period, the canopy water layer displays both a temperature 0.5°C cooler than the upper water column, and a much higher nutrient content, as shown in this work using a very simple original technique permitting to sample water with a minimal disturbance of the water column's vertical structure. Despite low nutrient concentrations in pore water, mean net fluxes were measured from the sediment to the canopy water. These fluxes are sufficient to provide 20% of the mean daily nitrogen and phosphorus requirement of the P. oceanica shoots. Conclusion An internal cycling of nutrients from P. oceanica senescent leaves was previously noted as an efficient strategy to help face low nutrient availability. The present study points out a second strategy which consists in holding back, in the canopy, the nutrients released at the water-sediment interface. This process occurs when long leaves, during poor nutrient periods in the water column, providing, to P. oceanica, the possibility to develop, high biomass, high chlorophyll quantities in low nutrient environment (a Low Nutrients High Chlorophyll system). PMID:12188926

  8. Nutrient profiles in retail cuts of bison meat

    Microsoft Academic Search

    J. K. Galbraith; G. Hauer; L. Helbig; Z. Wang; M. J. Marchello; L. A. Goonewardene

    2006-01-01

    The objectives were to determine the nutrient composition and variation in eight cuts of bison meat in bulls and heifers and identify nutrient relationships in the clod and sirloin by principal component analysis. The nutrients analyzed were: energy, protein, total fat, saturated fat, monounsaturated fat, polyunsaturated fat, transfat, cholesterol, vitamin A, Ca, Fe, Na and moisture. Differences were observed in

  9. Artificial Soil With Build-In Plant Nutrients

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W.; Allen, Earl; Henninger, Donald; Golden, D. C.

    1995-01-01

    Nutrients contained in sandlike material. Artificial soil provides nutrients to plants during several growing seasons without need to add fertilizer or nutrient solution. When watered, artificial soil slowly releases all materials a plant needs to grow. Developed as medium for growing crops in space. Also used to grow plants on Earth under controlled conditions or even to augment natural soil.

  10. Nutrient budget for Saguling Reservoir, West Java, Indonesia

    Microsoft Academic Search

    Barry T Hart; Wendy van Dok; Nani Djuangsih

    2002-01-01

    A preliminary nutrient budget for Saguling Reservoir is reported as a first attempt to quantify the behaviour of nutrients entering this reservoir. This work is part of a larger Indonesia–Australia collaborative research and training project, involving Padjadjaran University and Monash University, established to study nutrient dynamics in Saguling Reservoir.Saguling Reservoir, the first of a chain of three large reservoirs (Saguling,

  11. Can ectomycorrhizal weathering activity respond to host nutrient demands?

    E-print Network

    Bruns, Tom

    . This review examines what is known about how plants sense and respond to nutrient demand and discusses to minimize time between stand harvest without depleting mineral nutrient levels in the soil and to policyReview Can ectomycorrhizal weathering activity respond to host nutrient demands? Nicholas P

  12. Nutrients in the Great Lakes. Teacher's Guide and Student Workbook.

    ERIC Educational Resources Information Center

    Brothers, Chris; And Others

    This teacher guide and student workbook set presents two learning activities, designed for fifth through ninth grade students, that concentrate on nutrients in the Great Lakes. In activity A, students simulate aquatic habitats using lake water and goldfish in glass jars and observe the effects of nutrient loading and nutrient limitation on aquatic…

  13. Whole Farm Nutrient Balance Calculator for New York Dairy Farms

    ERIC Educational Resources Information Center

    Soberon, Melanie A.; Ketterings, Quirine M.; Rasmussen, Caroline N.; Czymmek, Karl J.

    2013-01-01

    Nutrient loss and accumulation as well as associated environmental degradation have been a concern for animal agriculture for many decades. Federal and New York (NY) regulations apply to Concentrated Animal Feeding Operations and a comprehensive nutrient management plan (CNMP) is required for regulated farms. The whole farm nutrient mass balance…

  14. Vertical Nutrient Distributions in the Western North Pacific Ocean: Simple Model for Estimating Nutrient Upwelling, Export Flux and Consumption Rates

    Microsoft Academic Search

    KATSUMI HIROSE; HITOMI KAMIYA

    2003-01-01

    A one-dimensional, steady-state model has been developed to understand the factors controlling vertical distributions of nutrients such as nitrate and phosphate in the western North Pacific water columns. The model includes simple physics and some biogeochemical processes. Nutrients are supplied by upwelling of nutrient-rich deep waters with a constant upwelling velocity and nutrient regeneration due to decompo- sition of sinking

  15. Assessment of Nutrient Stability in Space Foods

    NASA Technical Reports Server (NTRS)

    Zwart, S. R.; Perchonok, M.; Braby, L. A.; Kloeris, V. A.; Smith, S. M.

    2009-01-01

    Maintaining an intact nutrient supply in the food system flown on spacecraft is a critical issue for mission success and crew health and safety. Early polar expeditions and exploration expeditions by sailing vessels have taught us that a deficiency, or excess, of even a single vitamin in the food supply can be catastrophic. Evidence from ground-based research indicates that some vitamins are destroyed and fatty acids are oxidized (and therefore rendered dangerous or useless) by different types of radiation and by conditions of long-term storage. We hypothesize that radiation and long-term storage in the space-flight environment will affect the stability of vitamins, amino acids, and fatty acids in the space food system. The research objectives of our ongoing stability studies are to determine the stability of water- and fat-soluble vitamins, fatty acids, and amino acids in the space food supply before and after space flight on the International Space Station (ISS). Foods were analyzed after 2 weeks (a flight control), 11, 19, and 28 months of flight. Along with the space-flown foods, ground-based controls matched for time, light, and temperature are analyzed. The flight studies complement planned ground-based studies of the effects of radiation on vitamins, amino acids, and fatty acids. Flight studies are needed because a model based on ground-based data cannot predict all of the effects of the space-flight environment. Flight studies provide a more accurate test system to determine the effects on these nutrients of the temperature, and radiation conditions in the space-flight environment. Ground studies are required to evaluate longer missions and higher radiation levels expected outside low-Earth orbit. In addition to providing information about nutrient stability in space, the results of these studies will help NASA determine if a need exists to develop special packaging that can ensure stability of foods and nutrients in space, or if further studies of nutrient metabolism or nutrient requirements are needed.

  16. Nutrient-Dense Food Groups Have High Energy Costs: An Econometric Approach to Nutrient Profiling1,2

    Microsoft Academic Search

    Matthieu Maillot; Nicole Darmon; Michel Darmon; Lionel Lafay; Adam Drewnowski

    Consumers wishing to replace some of the foods in their diets with more nutrient-dense options need to be able to identify such foods on the basis of nutrient profiling. The present study used nutrient profiling to rank 7 major food groups and 25 subgroups in terms of their contribution to dietary energy, diet quality, and diet cost for 1332 adult

  17. Development of a nutrient pollution indicator using the seagrass, Zostera marina, along nutrient gradients in three New England estuaries

    Microsoft Academic Search

    Kun-Seop Lee; Frederick T Short; David M Burdick

    2004-01-01

    Worldwide, seagrasses provide important habitats in coastal ecosystems, but seagrass meadows are often degraded or destroyed by cultural eutrophication. Presently, there are no available tools for early assessment of nutrient over-enrichment; direct measurements of water column nutrients are ineffective since the nutrients typical of early enrichment are rapidly taken up by plants within the ecosystem. We investigated whether, in a

  18. Obesity: interactions of genome and nutrients intake.

    PubMed

    Doo, Miae; Kim, Yangha

    2015-03-01

    Obesity has become one of the major public health problems all over the world. Recent novel eras of research are opening for the effective management of obesity though gene and nutrient intake interactions because the causes of obesity are complex and multifactorial. Through GWASs (genome-wide association studies) and genetic variations (SNPs, single nucleotide polymorphisms), as the genetic factors are likely to determine individuals' obesity predisposition. The understanding of genetic approaches in nutritional sciences is referred as "nutrigenomics". Nutrigenomics explores the interaction between genetic factors and dietary nutrient intake on various disease phenotypes such as obesity. Therefore, this novel approach might suggest a solution for the effective prevention and treatment of obesity through individual genetic profiles and help improve health conditions. PMID:25866743

  19. Porous membrane utilization in plant nutrient delivery

    NASA Technical Reports Server (NTRS)

    Dreschel, T. W.; Hinkle, C. R.; Prince, R. P.; Knott, W. M., III

    1987-01-01

    A spacecraft hydroponic plant growth unit of tubular configuration, employing a microporous membrane as a capilary interface between plant roots and a nutrient solution, is presented. All three of the experimental trials undertaken successfully grew wheat from seed to harvest. Attention is given to the mass/seed, number of seeds/head, ratio of seed dry mass to total plant dry mass, production of tillers, and mass of seed/plant. Dry matter production is found to be reduced with increasing suction pressure; this is true for both average seed and average total dry matter/plant. This may be due to a reduction in water and nutrient availability through the microporous membrane.

  20. Plants integrate information about nutrients and neighbors.

    PubMed

    Cahill, James F; McNickle, Gordon G; Haag, Joshua J; Lamb, Eric G; Nyanumba, Samson M; St Clair, Colleen Cassady

    2010-06-25

    Animals regularly integrate information about the location of resources and the presence of competitors, altering their foraging behavior accordingly. We studied the annual plant Abutilon theophrasti to determine whether a plant can demonstrate a similarly complex response to two conditions: presence of a competitor and heterogeneous resource distributions. Individually grown plants fully explored the pot by using a broad and uniform rooting distribution regardless of soil resource distributions. Plants with competitors and uniform soil nutrient distributions exhibited pronounced reductions in rooting breadth and spatial soil segregation among the competing individuals. In contrast, plants with competitors and heterogeneous soil nutrient distributions reduced their root growth only modestly, indicating that plants integrate information about both neighbor and resource distributions in determining their root behavior. PMID:20576883

  1. Nutrient detection by incretin hormone secreting cells

    PubMed Central

    Diakogiannaki, Eleftheria; Gribble, Fiona M.; Reimann, Frank

    2012-01-01

    The hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulintropic polypeptide (GIP) are secreted after a meal. Like other enteroendocrine hormones they help to orchestrate the bodies' response to the availability of newly absorbable nutrients and are noteworthy as they stimulate postprandial insulin secretion, underlying what is known as the incretin effect. GLP-1-mimetics are now widely used in the treatment of type 2 diabetes and advantages over older insulinotropic therapies include weight loss. An alternative treatment regime might be the recruitment of endogenous GLP-1, however, very little is known about the physiological control of enteroendocrine responses. This review focuses on the molecular mechanisms to detect nutrient arrival in the gut that have been implicated within the incretin secreting cells. PMID:22182802

  2. Seasonal sediment and nutrient transport patterns.

    PubMed

    Moriasi, D N; Guzman, J A; Steiner, J L; Starks, P J; Garbrecht, J D

    2014-07-01

    It is essential to understand sediment and nutrient sources and their spatial and temporal patterns to design effective mitigation strategies. However, long-term data sets to determine sediment and nutrient loadings are scarce and expensive to collect. The goal of this study was to determine seasonal patterns of suspended sediment (SS), total N (TN), and total P (TP) concentrations and loadings for three USGS gauge sites located at the Fort Cobb Reservoir Experimental watershed (FCREW) located in southwestern Oklahoma. Measured instantaneous discharge, SS, TN, and TP concentration data were used to develop lognormal water quality-discharge relationships. The water quality-discharge relationships were used to generate estimated seasonal concentrations and loads based on hourly or 30-min interval discharge. The estimated concentrations and loads were used to determine seasonal patterns for SS, TN, and TP relative to the respective state water quality criteria. Decreasing and increasing monotonic trends were observed for the seasonal time series loads for all three sites, but they were insignificant based on the Spearman test (? = 0.05). The largest loads were estimated during the wet springs and summers. The study SS, TN, and TP target concentrations were exceeded in one season or another. The study results showed that the priority locations to implement the TN and TP conservation practices were the Lake Creek and Willow Creek subwatersheds during the winter and spring seasons. Common practices to mitigate nutrients and suspended sediments include nutrient management, no-till, conversion of cultivated land to pasture, riparian buffers, and animal exclusion. PMID:25603081

  3. Chasing Nutrients with an Arctic Sedge

    NASA Astrophysics Data System (ADS)

    Iverson, S. L.; Schimel, J.

    2013-12-01

    Climate change has put the Arctic into a state of flux. Understanding the effects an altered climate will have on vegetation and nutrient cycling requires more knowledge of the key plant and soil functions of major arctic ecosystems. One of these ecosystems, moist acidic tussock tundra, is dominated by a single plant species, the tussock-forming sedge Eriophorum vaginatum. This plant has unusual underground biomass: long, fast-growing, non-branching, non-mycorrhizal roots. In contrast to many other plants in nutrient-limiting environments, this sedge is highly successful without maximizing its root surface area to volume ratio. The benefits of this growth strategy to the plants and its effects on the accompanying soil-microbe-plant relationships are not fully understood. One possibility is that the roots may help the plant take advantage of nutrients released into the active layer of soil as it thaws in the spring. The roots may also stimulate microbial activity, increasing nutrient turnover and availability. A study was undertaken to explore the nitrogen (N) and carbon (C) dynamics in these plants, as well as the microbial populations associated with active E. vaginatum roots. Intact tussock microcosms (plant and accompanying soil) were removed from the tundra and cultivated in transparent boxes. Half the plants were kept in light to encourage photosynthesis (and thus greater plant activity), while the other half was kept in the dark to inhibit it. Using a 15N isotopic tracer injected at the extremity of root penetration into the soil, the N uptake capacity of E. vaginatum roots at depth was explored. This uptake capacity is compared to measures of plant activity, microbial activity, and soil solution chemistry in order to paint a clearer picture of the role of E. vaginatum in the soil ecosystem.

  4. Nutrient profiling schemes: overview and comparative analysis

    Microsoft Academic Search

    Marcella Garsetti; Jan de Vries; Maurice Smith; Amélie Amosse; Nathalie Rolf-Pedersen

    2007-01-01

    Nutrient profiling is a discipline aimed at classifying foods based on their nutritional composition. So far, several profiling\\u000a schemes have been proposed for varied purposes world-wide. Primary aim to inventory the main profiling schemes that have been\\u000a developed so far (both applied and not) and to summarise their main aspects. Secondary aim to critically review a selection\\u000a of them, to

  5. Anthropogenic nutrients and harmful algae in coastal waters.

    PubMed

    Davidson, Keith; Gowen, Richard J; Harrison, Paul J; Fleming, Lora E; Hoagland, Porter; Moschonas, Grigorios

    2014-12-15

    Harmful algal blooms (HABs) are thought to be increasing in coastal waters worldwide. Anthropogenic nutrient enrichment has been proposed as a principal causative factor of this increase through elevated inorganic and/or organic nutrient concentrations and modified nutrient ratios. We assess: 1) the level of understanding of the link between the amount, form and ratio of anthropogenic nutrients and HABs; 2) the evidence for a link between anthropogenically generated HABs and negative impacts on human health; and 3) the economic implications of anthropogenic nutrient/HAB interactions. We demonstrate that an anthropogenic nutrient-HAB link is far from universal, and where it has been demonstrated, it is most frequently associated with high biomass rather than low biomass (biotoxin producing) HABs. While organic nutrients have been shown to support the growth of a range of HAB species, insufficient evidence exists to clearly establish if these nutrients specifically promote the growth of harmful species in preference to benign ones, or if/how they influence toxicity of harmful species. We conclude that the role of anthropogenic nutrients in promoting HABs is site-specific, with hydrodynamic processes often determining whether blooms occur. We also find a lack of evidence of widespread significant adverse health impacts from anthropogenic nutrient-generated HABs, although this may be partly due to a lack of human/animal health and HAB monitoring. Detailed economic evaluation and cost/benefit analysis of the impact of anthropogenically generated HABs, or nutrient reduction schemes to alleviate them, is also frequently lacking. PMID:25173729

  6. The role of arbuscular mycorrhizas in reducing soil nutrient loss.

    PubMed

    Cavagnaro, Timothy R; Bender, S Franz; Asghari, Hamid R; Heijden, Marcel G A van der

    2015-05-01

    Substantial amounts of nutrients are lost from soils via leaching and as gaseous emissions. These losses can be environmentally damaging and expensive in terms of lost agricultural production. Plants have evolved many traits to optimize nutrient acquisition, including the formation of arbuscular mycorrhizas (AM), associations of plant roots with fungi that acquire soil nutrients. There is emerging evidence that AM have the ability to reduce nutrient loss from soils by enlarging the nutrient interception zone and preventing nutrient loss after rain-induced leaching events. Until recently, this important ecosystem service of AM had been largely overlooked. Here we review the role of AM in reducing nutrient loss and conclude that this role cannot be ignored if we are to increase global food production in an environmentally sustainable manner. PMID:25840500

  7. The role of autophagy in intracellular pathogen nutrient acquisition

    PubMed Central

    Steele, Shaun; Brunton, Jason; Kawula, Thomas

    2015-01-01

    Following entry into host cells intracellular pathogens must simultaneously evade innate host defense mechanisms and acquire energy and anabolic substrates from the nutrient-limited intracellular environment. Most of the potential intracellular nutrient sources are stored within complex macromolecules that are not immediately accessible by intracellular pathogens. To obtain nutrients for proliferation, intracellular pathogens must compete with the host cell for newly-imported simple nutrients or degrade host nutrient storage structures into their constituent components (fatty acids, carbohydrates, and amino acids). It is becoming increasingly evident that intracellular pathogens have evolved a wide variety of strategies to accomplish this task. One recurrent microbial strategy is to exploit host degradative processes that break down host macromolecules into simple nutrients that the microbe can use. Herein we focus on how a subset of bacterial, viral, and eukaryotic pathogens leverage the host process of autophagy to acquire nutrients that support their growth within infected cells.

  8. Nutrient flows between ecosystems can destabilize simple food chains.

    PubMed

    Marleau, Justin N; Guichard, Frédéric; Mallard, François; Loreau, Michel

    2010-09-01

    Dispersal of organisms has large effects on the dynamics and stability of populations and communities. However, current metacommunity theory largely ignores how the flows of limiting nutrients across ecosystems can influence communities. We studied a meta-ecosystem model where two autotroph-consumer communities are spatially coupled through the diffusion of the limiting nutrient. We analyzed regional and local stability, as well as spatial and temporal synchrony to elucidate the impacts of nutrient recycling and diffusion on trophic dynamics. We show that nutrient diffusion is capable of inducing asynchronous local destabilization of biotic compartments through a diffusion-induced spatiotemporal bifurcation. Nutrient recycling interacts with nutrient diffusion and influences the susceptibility of the meta-ecosystem to diffusion-induced instabilities. This interaction between nutrient recycling and transport is further shown to depend on ecosystem enrichment. It more generally emphasizes the importance of meta-ecosystem theory for predicting species persistence and distribution in managed ecosystems. PMID:20600133

  9. Nutrient Sensing Nuclear Receptors Coordinate Autophagy

    PubMed Central

    Lee, Jae Man; Wagner, Martin; Xiao, Rui; Kim, Kang Ho; Feng, Dan; Lazar, Mitchell A.; Moore, David D.

    2014-01-01

    Autophagy is an evolutionally conserved catabolic process that recycles nutrients upon starvation and maintains cellular energy homeostasis1–3. Its acute regulation by nutrient sensing signaling pathways is well described, but its longer-term transcriptional regulation is not. The nuclear receptors PPAR? and FXR are activated in the fasted or fed liver, respectively4,5. Here we show that both regulate hepatic autophagy. Pharmacologic activation of PPAR? reverses the normal suppression of autophagy in the fed state, inducing autophagic lipid degradation, or lipophagy. This response is lost in PPAR? knockout (PPAR??/?) mice, which are partially defective in the induction of autophagy by fasting. Pharmacologic activation of the bile acid receptor FXR strongly suppresses the induction of autophagy in the fasting state, and this response is absent in FXR knockout (FXR?/?) mice, which show a partial defect in suppression of hepatic autophagy in the fed state. PPAR? and FXR compete for binding to shared sites in autophagic gene promoters, with opposite transcriptional outputs. These results reveal complementary, interlocking mechanisms for regulation of autophagy by nutrient status. PMID:25383539

  10. Invasive aquarium fish transform ecosystem nutrient dynamics

    PubMed Central

    Capps, Krista A.; Flecker, Alexander S.

    2013-01-01

    Trade of ornamental aquatic species is a multi-billion dollar industry responsible for the introduction of myriad fishes into novel ecosystems. Although aquarium invaders have the potential to alter ecosystem function, regulation of the trade is minimal and little is known about the ecosystem-level consequences of invasion for all but a small number of aquarium species. Here, we demonstrate how ecological stoichiometry can be used as a framework to identify aquarium invaders with the potential to modify ecosystem processes. We show that explosive growth of an introduced population of stoichiometrically unique, phosphorus (P)-rich catfish in a river in southern Mexico significantly transformed stream nutrient dynamics by altering nutrient storage and remineralization rates. Notably, changes varied between elements; the P-rich fish acted as net sinks of P and net remineralizers of nitrogen. Results from this study suggest species-specific stoichiometry may be insightful for understanding how invasive species modify nutrient dynamics when their population densities and elemental composition differ substantially from native organisms. Risk analysis for potential aquarium imports should consider species traits such as body stoichiometry, which may increase the likelihood that an invasion will alter the structure and function of ecosystems. PMID:23966642

  11. Leaf mineral nutrient remobilization during leaf senescence and modulation by nutrient deficiency

    PubMed Central

    Maillard, Anne; Diquélou, Sylvain; Billard, Vincent; Laîné, Philippe; Garnica, Maria; Prudent, Marion; Garcia-Mina, José-Maria; Yvin, Jean-Claude; Ourry, Alain

    2015-01-01

    Higher plants have to cope with fluctuating mineral resource availability. However, strategies such as stimulation of root growth, increased transporter activities, and nutrient storage and remobilization have been mostly studied for only a few macronutrients. Leaves of cultivated crops (Zea mays, Brassica napus, Pisum sativum, Triticum aestivum, Hordeum vulgare) and tree species (Quercus robur, Populus nigra, Alnus glutinosa) grown under field conditions were harvested regularly during their life span and analyzed to evaluate the net mobilization of 13 nutrients during leaf senescence. While N was remobilized in all plant species with different efficiencies ranging from 40% (maize) to 90% (wheat), other macronutrients (K–P–S–Mg) were mobilized in most species. Ca and Mn, usually considered as having low phloem mobility were remobilized from leaves in wheat and barley. Leaf content of Cu–Mo–Ni–B–Fe–Zn decreased in some species, as a result of remobilization. Overall, wheat, barley and oak appeared to be the most efficient at remobilization while poplar and maize were the least efficient. Further experiments were performed with rapeseed plants subjected to individual nutrient deficiencies. Compared to field conditions, remobilization from leaves was similar (N–S–Cu) or increased by nutrient deficiency (K–P–Mg) while nutrient deficiency had no effect on Mo–Zn–B–Ca–Mn, which seemed to be non-mobile during leaf senescence under field conditions. However, Ca and Mn were largely mobilized from roots (-97 and -86% of their initial root contents, respectively) to shoots. Differences in remobilization between species and between nutrients are then discussed in relation to a range of putative mechanisms. PMID:26029223

  12. Leaf mineral nutrient remobilization during leaf senescence and modulation by nutrient deficiency.

    PubMed

    Maillard, Anne; Diquélou, Sylvain; Billard, Vincent; Laîné, Philippe; Garnica, Maria; Prudent, Marion; Garcia-Mina, José-Maria; Yvin, Jean-Claude; Ourry, Alain

    2015-01-01

    Higher plants have to cope with fluctuating mineral resource availability. However, strategies such as stimulation of root growth, increased transporter activities, and nutrient storage and remobilization have been mostly studied for only a few macronutrients. Leaves of cultivated crops (Zea mays, Brassica napus, Pisum sativum, Triticum aestivum, Hordeum vulgare) and tree species (Quercus robur, Populus nigra, Alnus glutinosa) grown under field conditions were harvested regularly during their life span and analyzed to evaluate the net mobilization of 13 nutrients during leaf senescence. While N was remobilized in all plant species with different efficiencies ranging from 40% (maize) to 90% (wheat), other macronutrients (K-P-S-Mg) were mobilized in most species. Ca and Mn, usually considered as having low phloem mobility were remobilized from leaves in wheat and barley. Leaf content of Cu-Mo-Ni-B-Fe-Zn decreased in some species, as a result of remobilization. Overall, wheat, barley and oak appeared to be the most efficient at remobilization while poplar and maize were the least efficient. Further experiments were performed with rapeseed plants subjected to individual nutrient deficiencies. Compared to field conditions, remobilization from leaves was similar (N-S-Cu) or increased by nutrient deficiency (K-P-Mg) while nutrient deficiency had no effect on Mo-Zn-B-Ca-Mn, which seemed to be non-mobile during leaf senescence under field conditions. However, Ca and Mn were largely mobilized from roots (-97 and -86% of their initial root contents, respectively) to shoots. Differences in remobilization between species and between nutrients are then discussed in relation to a range of putative mechanisms. PMID:26029223

  13. High fertigation frequency: the effects on uptake of nutrients, water and plant growth

    Microsoft Academic Search

    A. Silber; G. Xu; I. Levkovitch; S. Soriano; A. Bilu; R. Wallach

    2003-01-01

    The objective of the present research was to explore the effects of combined irrigation and fertilization (fertigation) frequency on growth, yield and uptake of water and nutritional elements by plants. Lettuce (Lactuca sativa L., cv. Iceberg) was used as the model plant. Two experiments were conducted in a screen-house: compound fertilizer at a constant N:P:K ratio at different concentrations was

  14. Enhancing crop growth, nutrients availability, economics and beneficial rhizosphere microflora through organic and biofertilizers

    Microsoft Academic Search

    Ghulam Jilani; Abida Akram; Raja M. Ali; Fauzia Y. Hafeez; Imran H. Shamsi; Arshad N. Chaudhry; Abid G. Chaudhry

    2007-01-01

    Field experiment was conducted on fodder maize to explore the potential of integrated use of chemical, organic and biofertilizers\\u000a for improving maize growth, beneficial microflora in the rhizosphere and the economic returns. The treatments were designed\\u000a to make comparison of NPK fertilizer with different combinations of half dose of NP with organic and biofertilizers viz. biological\\u000a potassium fertilizer (BPF), Biopower,

  15. Biological nutrient removal from dairy wastewater

    SciTech Connect

    Danalewich, J.R.; Papagiannis, T.G.; Gerards, R.; Vriens, L.; Belyea, R.; Tumbleson, M.E.; Raskin, L.

    1998-07-01

    The authors developed a synthetic wastewater which closely represents actual milk processing wastewater. The design of this synthetic wastewater was facilitated by the collection of composite wastewater samples from 15 milk processing plants in the Upper Midwest. These samples, milk, and milk products were analyzed for various chemical parameters. Based on these results, they diluted evaporated milk and cottage cheese, as well as a number of dry chemicals to create a synthetic wastewater. The concentrations in the resulting synthetic wastewater matched average concentrations of 15 composite wastewater samples. Four continuous-flow activated sludge treatment systems are currently being operated to evaluate biological nutrient removal using this synthetic wastewater as an influent.

  16. Nutrient-centrism and perceived risk of chronic disease.

    PubMed

    Schuldt, Jonathon P; Pearson, Adam R

    2015-06-01

    This experiment explored consequences of two common lay theories about the diet-disease link: nutrient-centrism, the belief that nutrients (e.g. potassium) are crucial to staving off disease, and whole-food centrism, the belief that whole foods (e.g. bananas), containing these nutrients in their natural context, are most beneficial. Depicting an individual's diet in terms of nutrients rather than whole foods containing these nutrients reduced the perceived likelihood that the individual would experience leading diet-related diseases (e.g. heart disease, diabetes). Although nutrition experts increasingly emphasize the health benefits of natural whole foods, people nevertheless appear to privilege nutrients when estimating disease risks. PMID:26032805

  17. Nutrient balances at farm level in Machakos (Kenya), using a participatory nutrient monitoring (NUTMON) approach

    Microsoft Academic Search

    L. N. Gachimbi; H. van Keulen; E. G. Thuranira; A. M. Karuku; A. de Jager; S. Nguluu; B. M. Ikombo; J. M. Kinama; J. K. Itabari; S. M. Nandwa

    2005-01-01

    A total of 74 farms were selected from Machakos, Mwingi and Makueni districts in Kenya, using participatory techniques and classified in three categories on the basis of soil fertility management (low level, medium and high level). Soil fertility management was monitored, using the NUTrient MONitoring methodology, which appears a suitable and appropriate tool for the diagnostic phase of Farming System

  18. Vertical gradient of nutrients in two dimictic lakes – influence of phototrophic sulfur bacteria on nutrient balance

    Microsoft Academic Search

    Uwe Selig; Thomas Hübener; Reinhard Heerkloss; Hendrik Schubert

    2004-01-01

    Vertical profiles of soluble and particulate nutrients were analyzed at the end of summer stratification in two dimictic lakes located in northeast Germany. In addition, irradiance and plankton biomass were determined. The concentrations of particulate organic carbon and phytoplankton biomass in the epilimnion were higher in Lake Tiefer than in Lake Dudinghausen, even though the apparent trophic status of Lake

  19. Nutrient content and variability in newly obtained salmon data for USDA Nutrient Database for Standard Reference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because different species, sources, and forms of salmon are now available, we sampled selected salmon products to determine variability of nutrient profiles from those items. Sample units of retail raw wild, raw farmed, and canned salmon were obtained from 12 locations using statistically valid samp...

  20. NUTRIENT TRANSPORT IN STARFISH. II. UPTAKE OF' NUTRIENTS BY ISOLATED ORGANS

    Microsoft Academic Search

    JOHN CARRUTHERS FERGUSON

    nutrient materials may be released from the storage tissues into the coelornic fluid,. (2) nutrientmaterialsmaybe extractedfromthe coelomic fluidby the tissuesre quiring them, and (3 ) these operations may occur at rates sufficient to satisfy the metabolic needs of the animals. These processes, common to most animals, may be quite readily studied in star fish. Several of the major organs of

  1. Effect of peanut hull and pine chip biochar on soil nutrients, corn nutrient status and yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyrolysis is the process of anaerobic thermal conversion of biomass for energy production that may offer an option of returning carbon and nutrients to the soil while producing energy. The Ultisols in the southeastern United States have inherently low soil organic carbon and fertility. These soils m...

  2. Nutrient ManagementNutrient Management Program in OklahomaProgram in Oklahoma

    E-print Network

    #12;Animal Waste Related Research Nutrient management Water quality Feed management Air quality? Regulation Education Research Teaching #12;Regulations On Animal WasteRegulations On Animal Waste ManagementManagement;Animal Waste ManagementAnimal Waste Management ExtensionExtension Prepared and implemented the required

  3. Nutrient limitation in the sea: dynamics, identification, and significance

    Microsoft Academic Search

    R. C. DUGDALE

    1967-01-01

    A mathematical model has been constructed to provide a thcorctical framework for the investigation and discussion of nutrient limitation in the sea. The euphotic zone is divided into nutrient-limited and light-limited regions. For simplicity, the regeneration term is ignored, and a steady state is assumed. The uptake of major nutrients is assumed to follow the Michaelis-Menton expression, and some data

  4. Physical Transport of Nutrients and the Maintenance of Biological Production

    Microsoft Academic Search

    Richard G. Williams; Michael J. Follows

    \\u000a The oceanic distributions of nutrients and patterns of biological production are controlled by the interplay of biogeochemical\\u000a and physical processes, and external sources. Biological and chemical processes lead to the transformation of nutrients between\\u000a inorganic and organic forms, and also between dissolved and particulate forms. Physical processes redistribute nutrients within\\u000a the water column through transport and mixing. The combined role

  5. Organic matter stability and nutrient availability in Taupo Pumice

    Microsoft Academic Search

    R. H. Jackman

    1960-01-01

    Soils derived from rhyolitic Taupo pumice when under permanent pasture accumulate organically bound nutrients in the top soil to a high degree. The available nutrient supply is thereby reduced.Respirometry studies show that this accumulation is not due to a reduced microbial activity resulting from a deficiency of a major or minor nutrient element.Raising the pH increases the microbial activity of

  6. Spanish children's diet: compliance with nutrient and food intake guidelines

    Microsoft Academic Search

    M A Royo-Bordonada; L Gorgojo; J M Martín-Moreno; C Garcés; F Rodríguez-Artalejo; M Benavente; A Mangas; M de Oya

    2003-01-01

    Objective: To compare the diet of Spanish children against the nutrient and food intake guidelines. To calculate an index of overall diet quality and check its validity against nutrient intake.Design and setting: Cross-sectional study in four cities in Spain, where information on food and nutrient intake was obtained from schoolchildren through a food frequency questionnaire.Participants: The sample included 1112 children

  7. The Diverse Nutrient Strategies of Harmful Algae: Focus on Osmotrophy

    Microsoft Academic Search

    P. M. Glibert; C. Legrand

    Organic forms of nutrients originate from various sources, natural and anthropogenic. Organic nutrients are, in turn, used\\u000a by many HAB species that have multiple acquisition mechanisms. The strategies for nutrient and carbon acquisition by HABs\\u000a are thus far more complex than were thought a decade or two ago. With the application of the host of methods now available\\u000a to characterize

  8. Non-nutritional uses of nutrients Richard J. Wurtman

    E-print Network

    Wurtman, Richard

    2011 Keywords: Carbohydrates Tryptophan Uridine Blood­brain barrier Neurotransmitter Synaptogenesis, and thus promote synaptogenesis. In order for the nutrient to produce such effects, its plasma levels must

  9. The Plant Ionome Revisited by the Nutrient Balance Concept

    PubMed Central

    Parent, Serge-Étienne; Parent, Léon Etienne; Egozcue, Juan José; Rozane, Danilo-Eduardo; Hernandes, Amanda; Lapointe, Line; Hébert-Gentile, Valérie; Naess, Kristine; Marchand, Sébastien; Lafond, Jean; Mattos, Dirceu; Barlow, Philip; Natale, William

    2013-01-01

    Tissue analysis is commonly used in ecology and agronomy to portray plant nutrient signatures. Nutrient concentration data, or ionomes, belong to the compositional data class, i.e., multivariate data that are proportions of some whole, hence carrying important numerical properties. Statistics computed across raw or ordinary log-transformed nutrient data are intrinsically biased, hence possibly leading to wrong inferences. Our objective was to present a sound and robust approach based on a novel nutrient balance concept to classify plant ionomes. We analyzed leaf N, P, K, Ca, and Mg of two wild and six domesticated fruit species from Canada, Brazil, and New Zealand sampled during reproductive stages. Nutrient concentrations were (1) analyzed without transformation, (2) ordinary log-transformed as commonly but incorrectly applied in practice, (3) additive log-ratio (alr) transformed as surrogate to stoichiometric rules, and (4) converted to isometric log-ratios (ilr) arranged as sound nutrient balance variables. Raw concentration and ordinary log transformation both led to biased multivariate analysis due to redundancy between interacting nutrients. The alr- and ilr-transformed data provided unbiased discriminant analyses of plant ionomes, where wild and domesticated species formed distinct groups and the ionomes of species and cultivars were differentiated without numerical bias. The ilr nutrient balance concept is preferable to alr, because the ilr technique projects the most important interactions between nutrients into a convenient Euclidean space. This novel numerical approach allows rectifying historical biases and supervising phenotypic plasticity in plant nutrition studies. PMID:23526060

  10. Autophagy, plant senescence, and nutrient recycling.

    PubMed

    Avila-Ospina, Liliana; Moison, Michael; Yoshimoto, Kohki; Masclaux-Daubresse, Céline

    2014-07-01

    Large numbers of publications have appeared over the last few years, dealing with the molecular details of the regulation and process of the autophagy machinery in animals, plants, and unicellular eukaryotic organisms. This strong interest is caused by the fact that the autophagic process is involved in the adaptation of organisms to their environment and to stressful conditions, thereby contributing to cell and organism survival and longevity. In plants, as in other eukaryotes, autophagy is associated with longevity as mutants display early and strong leaf senescence symptoms, however, the exact role of autophagy as a pro-survival or pro-death process is unclear. Recently, evidence that autophagy participates in nitrogen remobilization has been provided, but the duality of the role of autophagy in leaf longevity and/or nutrient recycling through cell component catabolism remains. This review aims to give an overview of leaf senescence-associated processes from the physiological point of view and to discuss relationships between nutrient recycling, proteolysis, and autophagy. The dual role of autophagy as a pro-survival or pro-death process is discussed. PMID:24687977

  11. Plant Available Nutrients, Barrow, Alaska, Ver. 1

    DOE Data Explorer

    Sloan, Victoria; Liebig, Jenny; Curtis, Bryan; Hahn, Melanie; Iversen, Colleen; Siegrist, Julie

    This dataset consists of measurements of plant available nutrients made using Plant Root Simulator probes (Western Ag Innovations Inc.) during 2012 and 2013. In 2012, Ca, Mg, K, P, Fe, Mn, Cu, Zn, B, S, Pb, Al, Cd, NO3-N and NH4-N were measured during spring, summer and winter in the centers, edges and troughs of four polygons in each of four areas of contrasting moisture regime and polygon type. In 2013, probes were installed in centers, edges and troughs of four polygons in each of two areas (high-centered and low-centered polygons) at two-week intervals and at 3 soil depths to capture fine-scale season dynamics of NO3-N and NH4-N. PRS probes are ion exchange resin membranes held in plastic supports that are inserted into soil to measure ion supply in situ. The anion and cation exchange with the membrane is intended to mimic plant uptake and thus provide a relevant measure of soil nutrient bioavailability. Measurements are made per area of probe membrane and cannot be converted to concentrations or related to soil volume.

  12. Plant Available Nutrients, Barrow, Alaska, Ver. 1

    SciTech Connect

    Sloan, Victoria; Liebig, Jenny; Curtis, Bryan; Hahn, Melanie; Iversen, Colleen; Siegrist, Julie

    2014-02-19

    This dataset consists of measurements of plant available nutrients made using Plant Root Simulator probes (Western Ag Innovations Inc.) during 2012 and 2013. In 2012, Ca, Mg, K, P, Fe, Mn, Cu, Zn, B, S, Pb, Al, Cd, NO3-N and NH4-N were measured during spring, summer and winter in the centers, edges and troughs of four polygons in each of four areas of contrasting moisture regime and polygon type. In 2013, probes were installed in centers, edges and troughs of four polygons in each of two areas (high-centered and low-centered polygons) at two-week intervals and at 3 soil depths to capture fine-scale season dynamics of NO3-N and NH4-N. PRS probes are ion exchange resin membranes held in plastic supports that are inserted into soil to measure ion supply in situ. The anion and cation exchange with the membrane is intended to mimic plant uptake and thus provide a relevant measure of soil nutrient bioavailability. Measurements are made per area of probe membrane and cannot be converted to concentrations or related to soil volume.

  13. Nutrient Enrichment Drives Gulf of Mexico Hypoxia

    NASA Astrophysics Data System (ADS)

    Boesch, Donald F.; Boynton, Walter R.; Crowder, Larry B.; Diaz, Robert J.; Howarth, Robert W.; Mee, Laurence D.; Nixon, Scott W.; Rabalais, Nancy N.; Rosenberg, Rutger; Sanders, James G.; Scavia, Donald; Turner, R. Eugene

    2009-04-01

    During most summers over the past 30 years, bottom dissolved oxygen across a large area of the Louisiana and upper Texas continental shelf declined to concentrations too low (hypoxia) for most fish and large invertebrate animals to survive. This area is one of the best known “dead zones” proliferating around the world [Diaz and Rosenberg, 2008]. During July 2008, hypoxic bottom waters extended across 20,720 square kilometers (Figure 1), but they were probably even more extensive because winds from Hurricane Dolly mixed the waters off Texas before the survey could be completed. Increased inputs of nutrients (principally nitrogen and phosphorus) from the U.S. agricultural heartland within the Mississippi-Atchafalaya River Basin (MARB) are implicated in the development and spread of hypoxia in the Gulf of Mexico. Consequently, the causes of, and solutions for, hypoxia have been subjects of extensive debate and analysis. An integrated scientific assessment led to a 2001 Action Plan [Mississippi River/Gulf of Mexico Watershed Nutrient Task Force, 2001] with a goal of reducing the area of the hypoxic zone to less than 5000 square kilometers by reducing nitrogen loading [Rabalais et al., 2007].

  14. Lateral Diffusion of Nutrients by Mammalian Herbivores in Terrestrial Ecosystems

    PubMed Central

    Wolf, Adam; Doughty, Christopher E.; Malhi, Yadvinder

    2013-01-01

    Animals translocate nutrients by consuming nutrients at one point and excreting them or dying at another location. Such lateral fluxes may be an important mechanism of nutrient supply in many ecosystems, but lack quantification and a systematic theoretical framework for their evaluation. This paper presents a mathematical framework for quantifying such fluxes in the context of mammalian herbivores. We develop an expression for lateral diffusion of a nutrient, where the diffusivity is a biologically determined parameter depending on the characteristics of mammals occupying the domain, including size-dependent phenomena such as day range, metabolic demand, food passage time, and population size. Three findings stand out: (a) Scaling law-derived estimates of diffusion parameters are comparable to estimates calculated from estimates of each coefficient gathered from primary literature. (b) The diffusion term due to transport of nutrients in dung is orders of magnitude large than the coefficient representing nutrients in bodymass. (c) The scaling coefficients show that large herbivores make a disproportionate contribution to lateral nutrient transfer. We apply the diffusion equation to a case study of Kruger National Park to estimate the conditions under which mammal-driven nutrient transport is comparable in magnitude to other (abiotic) nutrient fluxes (inputs and losses). Finally, a global analysis of mammalian herbivore transport is presented, using a comprehensive database of contemporary animal distributions. We show that continents vary greatly in terms of the importance of animal-driven nutrient fluxes, and also that perturbations to nutrient cycles are potentially quite large if threatened large herbivores are driven to extinction. PMID:23951141

  15. Dynamics of inorganic nutrient species in the Bohai seawaters

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Yu, Z. G.; Raabe, T.; Liu, S. M.; Starke, A.; Zou, L.; Gao, H. W.; Brockmann, U.

    2004-02-01

    Within the frame of a Sino-German Joint Research Program, two cruises of "R/V Dong Fang Hong 2" were carried out in September-October 1998 and April-May 1999, respectively, to understand the dynamics of nutrients in the Bohai. Nutrient species (NO 3-, NO 2-, NH 4+, PO 43- and SiO 32-) are determined colorimetrically on board for five anchor and 30 grid stations. In situ incubation experiments are performed to determine planktonic nutrient uptake and benthic exchange flux. Nutrient concentrations display short-term variability and seasonal change in the Bohai, with higher levels in shallow coastal waters than in the Central Bohai. The influence of riverine discharge on nutrient levels can be seen from salinity isopleths, nutrient distribution and species ratios. Near-bottom (nb) waters have similar nutrient concentrations as to the surface waters in the Central Bohai, whereas stratification takes place in the Bohai Strait and North Yellow Sea. In situ incubation experiments provide evidence that the uptake ratio (i.e. N, P) by phytoplankton is proportional to the ratios among nutrient species in ambient waters. Based on the data of this study and previously publications, a preliminary estimate of nutrient budgets via riverine input and atmospheric deposition is established. The results indicate that atmospheric deposition gains importance over rivers in delivering nutrients into the Bohai and sustain the new production, following recent decrease in riverine inflow caused by drought periods in North China and damming practices. A historical review of nutrient data indicates that concentrations of nitrogen increase and phosphorus and silica decrease in the Central Bohai over last 40 years. This potentially has an important influence on the health of ecosystem in Bohai (e.g. food web and community structure), though further study is needed to examine the scenario in more detail.

  16. Nutrient recycling by Tropheus brichardi across a littoral productivity gradient in Lake Tanganyika

    Microsoft Academic Search

    Tana Hintz; Peter McIntyre

    Nutrient recycling occurs when nutrients are released into the environment by animals or microbial consumers. Fish-mediated nutrient recycling is an important source of nutrients for primary producers in many aquatic ecosystems, sometimes even exceeding external loading rates (Attayde and Hansson 2001). Consumers release non-assimilated nutrients as liquid waste that is available to primary producers or as feces that is available

  17. Nutrient Solution Prepared with Ozonated Water does not Damage Early Growth of Hydroponically Grown Tomatoes

    Microsoft Academic Search

    Keiko Ohashi-Kaneko; Mari Yoshii; Takeshi Isobe; Jong-Seok Park; Kenji Kurata; Kazuhiro Fujiwara

    2009-01-01

    Ozonated water as a water source for nutrient solution was investigated in hydroponically grown tomatoes. Nutrient solution was prepared by diluting concentrated nutrient solutions with ozonated water with dissolved ozone (DO3) concentrations of 0 to 10 mg L. Manganese concentration in the nutrient solution decreased with increasing DO3 concentrations. Initial growth of tomato plants supplied with nutrient solution prepared with

  18. Critical limits for nutrient concentrations and ratios for forest trees - a comment

    Microsoft Academic Search

    Walter Flückiger; Sabine Braun

    Many approaches have been made to get a better understanding of adequate ranges for nutrient concentrations and ratios of woody plants in respect of growth, cold hardiness and drought re- sistance as well as susceptibility of plants to parasite attacks. To define critical nutrient limits, nutrient ratios are more useful than nutrient concentrations. The ratios not only reflect nutrient balance

  19. THE USDA NATIONAL NUTRIENT DATABASE FOR WINDOWS, SR18 VERSION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Nutrient Data Laboratory (NDL) has released an easily searchable version of the USDA National Nutrient Database for Standard Reference, Rel. 18 (SR18) for use on personal computers using the Windows® Operating System, Windows® 98SE and above. This product is available for download, at no cost, f...

  20. Manure Application Under Winter Conditions: Nutrient Runoff and Leaching Losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter application of manure is commonly practiced and potential nutrient losses are difficult to predict. This study was conducted in order to determine nutrient losses via surface runoff and subsurface leachate from winter-applied manure based on its relative placement with respect to snow. A labo...

  1. Modeling seasonal export and retention of nutrients in european catchments

    Microsoft Academic Search

    J. de Klein

    2003-01-01

    In the abatement of eutrophication of standing waters management of sources and transport of nutrients in river catchments is crucial. However the transport of nitrogen and phosphorus can vary significantly among (sub) catchments as a result of different physical, chemical and biotic factors. Qualitative and quantitative differences in nutrient pathways within catchments hamper the application of common standards and reliable

  2. Ceratophyllum demersum – phosphorus interactions in nutrient enriched aquaria

    Microsoft Academic Search

    Paola Lombardo; G. Dennis Cooke

    2003-01-01

    High macrophyte density in shallow lakes is often associated with clear water, especially when the non-rooted, submerged angiosperm Ceratophyllum demersum is dominant. Lack of true roots and high surface area:volume ratio suggest that nutrient uptake from the water column by C. demersum may be high. Therefore, possible competition for nutrients, including phosphorus (P), could contribute to phytoplankton inhibition.

  3. Effects of broiler litter application on nutrient accumulation in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excessive nutrient accumulation in soils due to land application of broiler litter is a growing environmental concern. A four-year study was conducted on a Pembroke silt loam soil (Mollic Paleudalf) cropped to orchardgrass (Dactylis glomerata L.) to evaluate accumulation of soil nutrients from broil...

  4. Impacts of Agricultural Nutrient Regulation in a Heterogeneous Region

    Microsoft Academic Search

    Doug Parker; Erik Lichtenberg

    2004-01-01

    Nonpoint sources of water pollutants, in particular, nutrients like nitrogen and phosphorus, are increasingly a focus of US water pollution policy. In most cases, agriculture is the largest contributor of these pollutants, in part because, until recently, it has largely remained unregulated. Recently, however, a number of initiatives have targeted nutrient runoff and leaching from animal agriculture. Many states have

  5. Nutrient composition of poultry manures in England and Wales

    Microsoft Academic Search

    F. A. Nicholson; B. J. Chambers; K. A. Smith

    1996-01-01

    In this study, 121 poultry manure samples were collected from commercial holdings in England and Wales. The nutrient contents of the individual manure samples varied widely. In general, broiler\\/turkey litters had a higher dry matter content (c.60%) than layer manures (c.35%), although all manure types had similar concentrations of nutrients (N, P, K, Mg, S) on a dry weight basis.

  6. Nutrient values for Australian and overseas chicken meat

    Microsoft Academic Search

    Yasmine Probst

    2009-01-01

    Purpose – The purpose of this paper is to summarise analysed nutrient data for Australian chicken meat and compare analysed data for Australian chicken meat with overseas data. Design\\/methodology\\/approach – Analysed nutrient data for Australian chicken meat was compared with publicly available English language databases from overseas countries. Where similar cuts were available, ratio plots were developed to determine similarities

  7. Approaches for Development of Nutrient Criteria in Oregon Estuaries

    EPA Science Inventory

    Development of nutrient criteria for all water body types of the US remains a top priority for EPA. Estuaries in the Pacific Northwest receive nutrients from both the watershed and the coastal ocean, and thus are particularly complex systems in which to establish water quality c...

  8. SOUTHEASTERN PLAINS IN-STREAM NUTRIENT AND BIOLOGICAL RESPONSE (SPINBR)

    EPA Science Inventory

    States and EPA lack a tool to characterize and measure biological response to nutrients in flowing waters. This study is designed to describe, examine and characterize the relationship between biological response and aquatic nutrients as a potential causal variable along a gradi...

  9. Tech Manual Update Bulletin Pennsylvania's Nutrient Management Act Program

    E-print Network

    Kaye, Jason P.

    ............................................................................................... 5 PLAN UPDATES FOR NEW CROP YEARS The Act 38 Nutrient Management Program Technical Manual outlines years. One option is to plan for one crop year in the initial nutrient management plan. Updates", "Section V: Plan Review and Implementation", "Section II, Appendix 4: Crop & Manure Management Information

  10. Nutrient mitigation capacity in Mississippi Delta, USA drainage ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutrophication and hypoxia within aquatic systems are a serious international concern. Various management practices have been proposed to help alleviate nutrient loads transported to the Gulf of Mexico and other high-profile aquatic systems. The current study examined the nutrient mitigation capac...

  11. Manure application under winter conditions: Nutrient runoff and leaching losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter application of manure is commonly practiced and potential nutrient losses are difficult to predict. This study was conducted in order to determine nutrient losses via surface runoff and subsurface leachate from winter-applied manure based on its relative placement with respect to snow. A labo...

  12. Rice lines with high leaf mineral nutrient levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) and Potassium (K), and sometimes other mineral nutrients are often applied as fertilizer, in addition to Nitrogen, to help achieve high yields in Texas rice production. For some mineral nutrients, total levels in soil would be sufficient to support the desired rice crop growth, but th...

  13. Nutrient and grazing influences on a subtropical seagrass community

    E-print Network

    McGlathery, Karen

    parrotfish Sparisoma radians),were partitioned using roofless cages. Nutrient enrich- ment caused an increase or reduced seagrass growth from shading. Nutrient enrichment caused an increase in the nitrogen content the higher-nitrogen seagrass at the eutrophic site. Intense grazing on this nitrogen-enriched T

  14. Biochar impact on nutrient leaching from a Midwestern agricultural soil

    Microsoft Academic Search

    David Laird; Pierce Fleming; Baiqun Wang; Robert Horton; Douglas Karlen

    2010-01-01

    Application of biochar to highly weathered tropical soils has been shown to enhance soil quality and decrease leaching of nutrients. Little, however, is known about the effects of biochar applications on temperate region soils. Our objective was to quantify the impact of biochar on leaching of plant nutrients following application of swine manure to a typical Midwestern agricultural soil. Repacked

  15. An integrated study of nutrient leaching and greenhouse gas emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient leaching and greenhouse gas emission are two of the primary environmental impacts of crop production. These processes have been studied at great length separately, but few integrated studies of leaching and greenhouse gas emission have been conducted. We measured nutrient leaching and green...

  16. Nutrient Profiles – A Suitable Means of Nutrition Information

    Microsoft Academic Search

    Helmut F. Erbersdobler

    2007-01-01

    For several years, nutrient profiling has been discussed as a regulatory instrument for health claims made on foods. The aims of the European Commission are mainly to protect consumers from misleading and even dangerous information and to ban advertisements for foods and menus for children if they are not healthy. Generally, nutrient profiling will be established on the basis of

  17. Nutrient Transport in Tile-Fed Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage ditches receive water and associated contaminants from agricultural fields via surface runoff or sub-surface tile drains. Little consideration has been given to the processes affecting nutrient transport once in surface water. The objective of this research was to evaluate the nutrient fa...

  18. Original article Nutrient cycling in deciduous forest ecosystems

    E-print Network

    Paris-Sud XI, Université de

    Original article Nutrient cycling in deciduous forest ecosystems of the Sierra de Gata mountains - The present work fits into a general study on nutrient cycling in four Quercus pyrenaica oak forests and one from that of the oak forests. It is also possible to differentiate three groups of bioelements: 1

  19. The effect of sucrose application on soil nutrient availability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil nutrient availability is a principal factor constraining the invasiveness of exotic weeds such as cheatgrass (Bromus tectorum L.). The soil microbial community is generally C limited; thus, providing a labile C source can cause microbes to proliferate and immobilize soil nutrients, particularly...

  20. Effects of acid rain on forest nutrient status

    Microsoft Academic Search

    Dale W. Johnson; John Turner; J. M. Kelly

    1982-01-01

    The paper presents an extensive literature review that deals with the assessment of the effects of acidic atmospheric inputs on forest nutrient status within the context of natural, internal acid production by carbonic and organic acids as well as the nutrient inputs and drains by management practices such as harvesting, fire and fertilization. 123 refs.

  1. Nutrient and Pesticide Removal From Laboratory Simulated Tile Drainage Discharge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excess nutrient and pesticide transport through subsurface tile drainage is well documented. One approach receiving consideration for reducing the amount of nutrients and pesticides in subsurface drainage waters is end-of-tile filters. The filters are often comprised of industrial wastes or by-produ...

  2. Managing Manure Nutrients Through Multi-crop Forage Production

    Microsoft Academic Search

    G. L. Newton; J. K. Bernard; R. K. Hubbard; J. R. Allison; R. R. Lowrance; G. J. Gascho; R. N. Gates; G. Vellidis

    2003-01-01

    Concentrated sources of dairy manure represent sig- nificant water pollution potential. The southern USA may be more vulnerable to water quality problems than someotherregionsbecauseofclimate,typicalfarmsize, and cropping practices. Dairy manure can be an effec- tive source of plant nutrients and large quantities of nutrients can be recycled through forage production, especially when multi-cropping systems are utilized. Linkingforageproductionwithmanureutilizationisan environmentally sound approach for

  3. The Effects of Nutrient Dynamics on Root Patch Choice

    Microsoft Academic Search

    Hagai Shemesh; Adi Arbiv; Mordechai Gersani; Ofer Ovadia; Ariel Novoplansky; Hans Henrik Bruun

    2010-01-01

    Plants have been recognized to be capable of allocating more roots to rich patches in the soil. We tested the hypothesis that in addition to their sensitivity to absolute differences in nutrient availability, plants are also responsive to temporal changes in nutrient availability. Different roots of the same Pisum sativum plants were subjected to variable homogeneous and heterogeneous temporally –

  4. PROFITABLE AND SUSTAINABLE SOIL TEST-BASED NUTRIENT MANAGEMENT

    Microsoft Academic Search

    Parviz N. Soltanpour; Jorge A. Delgado

    2002-01-01

    Soil testing determines nutrient, lime, gypsum or S, leaching requirements for crops, and potential elemental toxicity to crops and\\/or their consumers. The majority of farmers do not use soil testing or use higher or lower than economic optimum nutrient rates. Shortcomings of the current soil testing methodology are inability to predict yields, large soil test spacial and temporal variability, inability

  5. Reference Condition Approach for Numeric Nutrient Criteria for Oregon Estuaries

    EPA Science Inventory

    Development of nutrient criteria for all water body types of the US remains a top priority for EPA. Estuaries in the Pacific Northwest receive nutrients from both the watershed and the coastal ocean, and thus are particularly complex systems in which to establish water quality c...

  6. Trophic Cascades, Nutrients, and Lake Productivity: Whole-Lake Experiments

    Microsoft Academic Search

    Stephen R. Carpenter; Jonathan J. Cole; James R. Hodgson; James F. Kitchell; Michael L. Pace; Darren Bade; Kathryn L. Cottingham; Timothy E. Essington; Jeffrey N. Houser; Daniel E. Schindler

    2001-01-01

    Responses of zooplankton, pelagic primary producers, planktonic bacteria, and CO2 exchange with the atmosphere were measured in four lakes with contrasting food webs under a range of nutrient enrichments during a seven-year period. Prior to enrichment, food webs were manipulated to create contrasts between piscivore dominance and plank- tivore dominance. Nutrient enrichments of inorganic nitrogen and phosphorus exhibited ratios of

  7. Methane productivity and nutrient recovery from manure Henrik B. Mller

    E-print Network

    Methane productivity and nutrient recovery from manure Henrik B. Møller Danish Institute of Agricultural Sciences Ph.D thesis BioCentrum-DTU Technical University of Denmark 2003 #12;Acknowledgements This thesis, entitled "Methane productivity and nutrient recovery from manure" is presented in partial

  8. Soil nutrient depletion by agricultural production in Southern Mali

    Microsoft Academic Search

    Floris van der Pol; Boubacar Traore

    1993-01-01

    The degree of soil mining by agricultural production in Southern Mali is assessed by calculating nutrient balances: differences between the amount of plant nutrients exported from the cultivated fields, and those added to the fields. Export processes include extraction by crops, losses due to leaching, to erosion, and to volatilization and denitrification. Inputs include applications of fertilizer and manure, restitution

  9. Mariculture: significant and expanding cause of coastal nutrient enrichment

    NASA Astrophysics Data System (ADS)

    Bouwman, Lex; Beusen, Arthur; Glibert, Patricia M.; Overbeek, Ciska; Pawlowski, Marcin; Herrera, Jorge; Mulsow, Sandor; Yu, Rencheng; Zhou, Mingjiang

    2013-12-01

    Mariculture (marine aquaculture) generates nutrient waste either through the excretion by the reared organisms, or through direct enrichment by, or remineralization of, externally applied feed inputs. Importantly, the waste from fish or shellfish cannot easily be managed, as most is in dissolved form and released directly to the aquatic environment. The release of dissolved and particulate nutrients by intensive mariculture results in increasing nutrient loads (finfish and crustaceans), and changes in nutrient stoichiometry (all mariculture types). Based on different scenarios, we project that nutrients from mariculture will increase up to six fold by 2050 with exceedance of the nutrient assimilative capacity in parts of the world where mariculture growth is already rapid. Increasing nutrient loads and altered nutrient forms (increased availability of reduced relative to oxidized forms of nitrogen) and/or stoichiometric proportions (altered nitrogen:phosphorus ratios) may promote an increase in harmful algal blooms (HABs) either directly or via stimulation of algae on which mixotrophic HABs may feed. HABs can kill or intoxicate the mariculture product with severe economic losses, and can increase risks to human health.

  10. Aquaculture pond fertilization impacts of nutrient input on production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ponds are a primary production system to a wide variety of freshwater fish species. Each species have specific and unique nutrient needs and successful pond fertilization is critical to a successful aquaculture enterprise. Aquaculture Pond Fertilization: Impacts of Nutrient Input on Production pro...

  11. Nutrient Management, Mississippi 2004 Larry Oldham, Ph.D.

    E-print Network

    of Cropping Management Systems for the Brown Loam Area of Mississippi Animal By-Product Related Nutrient Litter Management for Land Productivity and Water Quality: Forestry Component Comparison of PoultryNutrient Management, Mississippi 2004 Larry Oldham, Ph.D. Associate Extension Professor - Soils #12

  12. USDA updates nutrient values for fast food pizza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of quick service pizza has increased as Americans are spending more on food away from home. Pizza is consistently a primary Key Food in the USDA National Food and Nutrient Analysis Program (NFNAP) because it is a contributor of more than 14 nutrients of public health significance to the...

  13. The New Nutrient Management What It Means for You

    E-print Network

    Balser, Teri C.

    applied nutrients ­ add a P based standard reviewed at public hearing ­ add manure analysis from not apply nutrients to: fields eroding more than "T" (tolerable soil loss) established concentrated flow Restrictions When frozen or snow covered soil prevents effective incorporation · No N & P commercial fertilizer

  14. Effects of Soil Texture on Belowground Carbon and Nutrient

    E-print Network

    Neff, Jason

    ´, Brazil ABSTRACT Soil texture plays a key role in belowground C storage in forest ecosystems and stronglyEffects of Soil Texture on Belowground Carbon and Nutrient Storage in a Lowland Amazonian Forest influences nutrient availability and retention, particularly in highly weathered soils. We used field data

  15. Nutrient-contaminant (Pu) plant accumulation model

    SciTech Connect

    Cowan, C.E.; Jenne, E.A.; Simpson, J.C.; Cataldo, D.A.

    1981-12-01

    A model was developed which simulates the movement and daily accumulation of nutrients and contaminants in crop plants resulting from known physiological processes in the plant. In the model, the daily contaminant accumulation is governed by daily increase in plant biomass derived from photosynthesis and by the specified thermodynamic activity of the bioavailable contaminant species in soil or hydroponic solutin. Total accumulation and resulting concentration in the plant's root, stem and branch, leaf, and reproductive compartments can be simulated any time during the growing season. Parameters were estimated from data on plutonium accumulation in soybeans and the model was calibrated against this same data set. The plutonium distribution in the plant was found to be most sensitive to parameters related to leaf accumulation. Contamination at different times during the growing season resulted in a large change in predicted leaf accumulation but very little change in predicted accumulation in other plant parts except when contamination occurred very late in the growing season.

  16. Nutrient budgets for large Chinese estuaries and embayment

    NASA Astrophysics Data System (ADS)

    Liu, S. M.; Hong, G.-H.; Ye, X. W.; Zhang, J.; Jiang, X. L.

    2009-01-01

    Nutrient concentrations among the Chinese rivers and bays vary 10-75 fold depending on nutrient elements. The silicic acid levels in South China rivers are higher than those from North China rivers and the yields of dissolved silicate increased from the north to the south of China, indicating the effect of climate on weathering. The nutrient levels in Chinese rivers are higher than those from the large and less-disturbed world rivers such as Amazon and Zaire, but comparable to the values for European and North American polluted and eutrophic rivers like the Loire and Po. This may be ascribed to both of extensive leaching and influences from agricultural and domestic activities over the drainage basins of Chinese rivers. DIN:PO3-4 ratios in most of Chinese rivers and bays are higher (up to 2800) than the other rivers in the world. The atomic ratios of DIN to PO43- in the major Chinese rivers and embayment decrease in exponential trend with increase in the atomic ratios of PO43- to Si(OH)4, indicating that primary production in coastal environments changes with the nutrients transport when the urbanization develops to a certain extent, and the potential limited nutrient elements can be changed from phosphorus to nitrogen limitation, which can modify aquatic food webs and then the ocean ecosystem. A simple steady-state mass-balance box model was employed. The output shows that the estuaries and embayment behave as a sink or source of nutrients. For the major Chinese estuaries, both residual and mixing flow transport nutrients off the estuaries, and nutrient transport fluxes in summer is 3-4 fold that in winter except comparable for NH4+. These fluxes are 1.0-1.7 fold that estimated by timing riverine nutrient concentrations and freshwater discharge. For the major Chinese embayment, nutrient elements are transported to China Seas except PO43- and Si(OH)4 in Sanggou Bay and Jiaozhou Bay. Seasonally, nutrients transport fluxes off the bays in the summer are 2.2-7.0 fold that in the winter. In the embayment, the exchange flow dominated the water budgets, resulting in average system salinity approaching the China seas salinity where river discharge is limited. The major Chinese estuaries and embayment transport 1.0-3.1% of nitrogen, 0.2-0.5% of phosphorus and 3% of silicon necessary for phytoplankton growth for the China Seas. This demonstrates regenerated nutrients in water column and sediments and nutrients transport fluxes between the China Seas and open ocean play an important role for phytoplankton growth. Atmospheric deposition may be another important source of nutrients for the China Seas.

  17. Factors controlling nutrient availability to the developing fetus in ruminants.

    PubMed

    Dunlap, Kathrin A; Brown, Jacob D; Keith, Ashley B; Satterfield, M Carey

    2015-01-01

    Inadequate delivery of nutrients results in intrauterine growth restriction (IUGR), which is a leading cause of neonatal morbidity and mortality in livestock. In ruminants, inadequate nutrition during pregnancy is often prevalent due to frequent utilization of exensive forage based grazing systems, making them highly susceptible to changes in nutrient quality and availability. Delivery of nutrients to the fetus is dependent on a number of critical factors including placental growth and development, utero-placental blood flow, nutrient availability, and placental metabolism and transport capacity. Previous findings from our laboratory and others, highlight essential roles for amino acids and their metabolites in supporting normal fetal growth and development, as well as the critical role for amino acid transporters in nutrient delivery to the fetus. The focus of this review will be on the role of maternal nutrition on placental form and function as a regulator of fetal development in ruminants. PMID:25908972

  18. Optimal foraging for specific nutrients in predatory beetles.

    PubMed

    Jensen, Kim; Mayntz, David; Toft, Søren; Clissold, Fiona J; Hunt, John; Raubenheimer, David; Simpson, Stephen J

    2012-06-01

    Evolutionary theory predicts that animals should forage to maximize their fitness, which in predators is traditionally assumed equivalent to maximizing energy intake rather than balancing the intake of specific nutrients. We restricted female predatory ground beetles (Anchomenus dorsalis) to one of a range of diets varying in lipid and protein content, and showed that total egg production peaked at a target intake of both nutrients. Other beetles given a choice to feed from two diets differing only in protein and lipid composition selectively ingested nutrient combinations at this target intake. When restricted to nutritionally imbalanced diets, beetles balanced the over- and under-ingestion of lipid and protein around a nutrient composition that maximized egg production under those constrained circumstances. Selective foraging for specific nutrients in this predator thus maximizes its reproductive performance. Our findings have implications for predator foraging behaviour and in the structuring of ecological communities. PMID:22237910

  19. Nutrient Uptake: The Arbuscular Mycorrhiza Fungal Symbiosis as a Plant Nutrient Acquisition Strategy

    Microsoft Academic Search

    Elke Neumann; Eckhard George

    \\u000a Symbiotic association of roots with arbuscular mycorrhizal (AM) fungi is a very widespread strategy by which plants facilitate\\u000a their acquisition of mineral elements from the soil. Studies employing sophisticated methodology in the fields of in vitro\\u000a culture of AM colonized roots, microscopy, isotope labeling and molecular biology have shed light into the physiology of AM\\u000a fungal nutrient uptake, transport and

  20. The Coupling of Solution Chemistry to Plant Nutrient Demand in an on Demand Nutrient Delivery System

    NASA Technical Reports Server (NTRS)

    Savage, Wayne

    1998-01-01

    The goal of the proposal will be to determine the suitability of the DASI instrument in providing a signal that can be recognized and be utilized as an indicator of plant stress. The method to be utilized for evaluating stress is the presentation of an every increasing level of nutrient deficiency and salinity stress (addition of salt (NACl) or increasing concentration of balanced nutrient) while simultaneously recording spectral reflectance using the DASI instrument and monitoring the traditional processes of gas exchange and nutrient uptake parameters. In this manner, we will be able to directly compare the DASI measurements with known stresses as determined by the traditional gas exchange and nutrient uptake measures of stress. We anticipate that the DASI will provide a sensitive identifier of plant stress; recording signals of the resulting changes in plant metabolism in real time, far before any visible effects of stress could be observed. Thus, there is a potential for very early management intervention to correct a stress condition before damage could develop. The present response time for the observation of visual symptoms of plant stress is considerable and only provides an indication that a stress is present after it has been present for an extended period of time. Thus, the impact of a plant-based life support function will have already been significant. An additional benefit of this research to regenerative life support will be the characterization of a potential recovery scenario from various degrees of stress. The experimental approach to be employed includes the removal of the stress at various points in the stress gradient and the characterization of plant performance and reflectance spectra during recovery from various degrees of stress. Spectral reflectance imaging techniques have been developed and used to measure the biochemical composition of plants and relate these characteristics to the fluxes of biochemical elements within the ecosystem.

  1. Interactions between temperature and nutrients across levels of ecological organization.

    PubMed

    Cross, Wyatt F; Hood, James M; Benstead, Jonathan P; Huryn, Alexander D; Nelson, Daniel

    2015-03-01

    Temperature and nutrient availability play key roles in controlling the pathways and rates at which energy and materials move through ecosystems. These factors have also changed dramatically on Earth over the past century as human activities have intensified. Although significant effort has been devoted to understanding the role of temperature and nutrients in isolation, less is known about how these two factors interact to influence ecological processes. Recent advances in ecological stoichiometry and metabolic ecology provide a useful framework for making progress in this area, but conceptual synthesis and review are needed to help catalyze additional research. Here, we examine known and potential interactions between temperature and nutrients from a variety of physiological, community, and ecosystem perspectives. We first review patterns at the level of the individual, focusing on four traits--growth, respiration, body size, and elemental content--that should theoretically govern how temperature and nutrients interact to influence higher levels of biological organization. We next explore the interactive effects of temperature and nutrients on populations, communities, and food webs by synthesizing information related to community size spectra, biomass distributions, and elemental composition. We use metabolic theory to make predictions about how population-level secondary production should respond to interactions between temperature and resource supply, setting up qualitative predictions about the flows of energy and materials through metazoan food webs. Last, we examine how temperature-nutrient interactions influence processes at the whole-ecosystem level, focusing on apparent vs. intrinsic activation energies of ecosystem processes, how to represent temperature-nutrient interactions in ecosystem models, and patterns with respect to nutrient uptake and organic matter decomposition. We conclude that a better understanding of interactions between temperature and nutrients will be critical for developing realistic predictions about ecological responses to multiple, simultaneous drivers of global change, including climate warming and elevated nutrient supply. PMID:25400273

  2. Farmers' use of nutrient management: lessons from watershed case studies.

    PubMed

    Osmond, Deanna L; Hoag, Dana L K; Luloff, Al E; Meals, Donald W; Neas, Kathy

    2015-03-01

    Nutrient enrichment of water resources has degraded coastal waters throughout the world, including in the United States (e.g., Chesapeake Bay, Gulf of Mexico, and Neuse Estuary). Agricultural nonpoint sources have significant impacts on water resources. As a result, nutrient management planning is the primary tool recommended to reduce nutrient losses from agricultural fields. Its effectiveness requires nutrient management plans be used by farmers. There is little literature describing nutrient management decision-making. Here, two case studies are described that address this gap: (i) a synthesis of the National Institute of Food and Agriculture, the Conservation Effects Assessment Project, and (ii) field surveys from three nutrient-impaired river basins/watersheds in North Carolina (Neuse, Tar-Pamlico, and Jordan Lake drainage areas). Results indicate farmers generally did not fully apply nutrient management plans or follow basic soil test recommendations even when they had them. Farmers were found to be hesitant to apply N at university-recommended rates because they did not trust the recommendations, viewed abundant N as insurance, or used recommendations made by fertilizer dealers. Exceptions were noted when watershed education, technical support, and funding resources focused on nutrient management that included easing management demands, actively and consistently working directly with a small group of farmers, and providing significant resource allocations to fund agency personnel and cost-share funds to farmers. Without better dialogue with farmers and meaningful investment in strategies that reward farmers for taking what they perceive as risks relative to nutrient reduction, little progress in true adoption of nutrient management will be made. PMID:26023957

  3. Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato

    NASA Technical Reports Server (NTRS)

    McKeehen, J. D.; Mitchell, C. A.; Wheeler, R. M.; Bugbee, B.; Nielsen, S. S.

    1996-01-01

    Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS.

  4. Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato

    NASA Astrophysics Data System (ADS)

    McKeehen, J. D.; Mitchell, C. A.; Wheeler, R. M.; Bugbee, B.; Nielsen, S. S.

    Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO_2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS.

  5. Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato.

    PubMed

    McKeehen, J D; Mitchell, C A; Wheeler, R M; Bugbee, B; Nielsen, S S

    1996-01-01

    Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS. PMID:11538817

  6. Effects of Anthropogenic Nutrient Enrichment on Exotic and Restored Native Aquatic Vegetation 

    E-print Network

    Parnell, Allison

    2012-07-16

    Understanding how nutrient input into coastal wetlands influences aquatic vegetation and the fate of anthropogenic nutrient inputs can help improve water quality management plans. The goals of this study were to (1) compare nutrient concentrations...

  7. Evaluation of nutrient variability in highly consumed "fast foods" under the National Food and Nutrient Analysis Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    USDA's National Food and Nutrient Analysis Program generates means and standard errors (S.E.) of nutrients in foods from nationally representative sample sets used in dietary assessment and consumer education. However, genetic makeup, growing/shipping/storage conditions, preparation techniques, and ...

  8. Reference Materials for Determination of the Nutrient Composition of Foods: Results from USDA's National Food and Nutrient Analysis Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certified reference materials (CRMs) play a critical role in validating the accuracy of nutrient data for food samples. A number of available food CRMs of differing matrix composition have assigned concentrations for various nutrients, along with associated uncertainty intervals (UIs) for those valu...

  9. EFFECTS OF ROOT ZONE PH AND NUTRIENT CONCENTRATION ON THE GROWTH AND NUTRIENT UPTAKE OF TOMATO SEEDLINGS

    Microsoft Academic Search

    Yun-Im Kang; Jin-Myeon Park; Seung-Heui Kim; Nam-Jun Kang; Kyoung-Sub Park; Si-Young Lee; Byoung Ryong Jeong

    2011-01-01

    The effects of nutrient concentration and pH, two major chemical properties of soil, on plant responses were investigated with seedlings of tomato, which is widely grown in greenhouses, as the model plant. An experiment with four levels of nutrient concentration [None (NC 0), 1 (NC 1), 5 (NC 5), and 10 folds (NC 10)], in combination with three pH levels

  10. Growth and Nutrient Intakes of Human Milk-Fed Preterm Infants Provided With Extra Energy and Nutrients After Hospital Discharge

    Microsoft Academic Search

    Deborah L. O'Connor; Sobia Khan; Karen Weishuhn; Jennifer Vaughan; Douglas M. Campbell; Elizabeth Asztalos; Mark Feldman; Carol Westall; Hilary Whyte

    OBJECTIVES.The purpose of this pilot study was to determine whether mixing a multi- nutrient fortifier to approximately one half of the human milk fed each day for a finite period after discharge improves the nutrient intake and growth of predomi- nantly human milk-fed low birth weight infants. We also assessed the impact of this intervention on the exclusivity of human

  11. Enhanced nutrient removal in a modified step feed process treating municipal wastewater with different inflow distribution ratios and nutrient ratios.

    PubMed

    Ge, Shijian; Peng, Yongzhen; Wang, Shuying; Guo, Jianhua; Ma, Bin; Zhang, Liang; Cao, Xu

    2010-12-01

    A pilot-scale modified step feed process was proposed to enhance organics and nutrient (N and P) removal performance from municipal wastewater. It combined University of Cape Town (UCT) and step feed process. Effects of inflow distribution ratios and nutrients ratios were investigated. The highest removal efficiencies of 89% for chemical oxygen demanding (COD), 88% for total nitrogen (TN) and 93% for phosphorus were obtained, respectively, at the inflow distribution ratio of 40:30:30%. The phosphorus removal exhibited an upward trend with the increasing of influent COD/P and TN/P, and the nitrogen removal had a positive correlation with influent COD/TN. In addition, aerobic simultaneous nitrification and denitrification and anoxic denitrifying phosphorus uptake made a distinct contribution to enhance nutrient removal. The proposed system was demonstrated to be an attractive enhanced biological nutrient removal process for wastewater treatment plants due to relatively high nutrient removal, robust sludge settleability and energy savings. PMID:20650632

  12. Nutrient vectors and riparian nutrient processing in African semiarid savanna ecosystems

    USGS Publications Warehouse

    Jacobs, Shayne M.; Bechtold, J.S.; Biggs, H.C.; Grimm, N. B.; McClain, M.E.; Naiman, R.J.; Perakis, Steven S.; Pinay, G.; Scholes, M.C.

    2007-01-01

    This review article describes vectors for nitrogen and phosphorus delivery to riparian zones in semiarid African savannas, the processing of nutrients in the riparian zone and the effect of disturbance on these processes. Semiarid savannas exhibit sharp seasonality, complex hillslope hydrology and high spatial heterogeneity, all of which ultimately impact nutrient fluxes between riparian, upland and aquatic environments. Our review shows that strong environmental drivers such as fire and herbivory enhance nitrogen, phosphorus and sediment transport to lower slope positions by shaping vegetative patterns. These vectors differ significantly from other arid and semiarid ecosystems, and from mesic ecosystems where the impact of fire and herbivory are less pronounced and less predictable. Also unique is the presence of sodic soils in certain hillslopes, which substantially alters hydrological flowpaths and may act as a trap where nitrogen is immobilized while sediment and phosphorus transport is enhanced. Nutrients and sediments are also deposited in the riparian zone during seasonal, intermittent floods while, during the dry season, subsurface movement of water from the stream into riparian soils and vegetation further enrich riparian zones with nutrients. As is found in mesic ecosystems, nutrients are immobilized in semiarid riparian corridors through microbial and plant uptake, whereas dissimilatory processes such as denitrification may be important where labile nitrogen and carbon are in adequate supply and physical conditions are suitablea??such as in seeps, wallows created by animals, ephemeral wetlands and stream edges. Interaction between temporal hydrologic connectivity and spatial heterogeneity are disrupted by disturbances such as large floods and extended droughts, which may convert certain riparian patches from sinks to sources for nitrogen and phosphorus. In the face of increasing anthropogenic pressure, the scientific challenges are to provide a basic understanding of riparian biogeochemistry in semiarid African savannas to adequately address the temporal and spatial impact of disturbances, and to apply this knowledge to better regional land and water management. An integrated, multidisciplinary approach applied in protected as well as human-disturbed ecosystems in southern Africa is essential for underpinning a strong environmental basis for sustainable human-related expansion.

  13. Nutrient management effects on sweetpotato genotypes under controlled environment

    NASA Technical Reports Server (NTRS)

    David, P. P.; Bonsi, C. K.; Trotman, A. A.; Douglas, D. Z.

    1996-01-01

    Sweetpotato is one of several crops recommended by National Aeronautics and Space Administration (NASA) for bioregenerative life support studies. One of the objectives of the Tuskegee University NASA Center is to optimize growth conditions for adaptability of sweetpotatoes for closed bioregenerative systems. The role of nutrient solution management as it impacts yield has been one of the major thrusts in these studies. Nutrient solution management protocol currently used consists of a modified half Hoagland solution that is changed at 14-day intervals. Reservoirs are refilled with deionized water if the volume of the nutrient solution was reduced to 8 liters or less before the time of solution change. There is the need to recycle and replenish nutrient solution during crop growth, rather than discard at 14 day intervals as previously done, in order to reduce waste. Experiments were conducted in an environmental growth room to examine the effects of container size on the growth of several sweetpotato genotypes grown under a nutrient replenishment protocol. Plants were grown from vine cuttings of 15cm length and were planted in 0.15 x 0.15 x 1.2m growth channels using a closed nutrient film technique system. Nutrient was supplied in a modified half strength Hoagland's solution with a 1:2.4 N:K ratio. Nutrient replenishment protocol consisted of daily water replenishment to a constant volume of 30.4 liters in the small containers and 273.6 liters in the large container. Nutrients were replenished as needed when the EC of the nutrient solution fell below 1200 mhos/cm. The experimental design used was a split-plot with the main plot being container size and genotypes as the subplot. Nine sweetpotato genotypes were evaluated. Results showed no effect of nutrient solution container size on storage root yield, foliage fresh and dry mass, leaf area or vine length. However, plants grown using the large nutrient solution container accumulated more storage root dry mass than those with the small containers. Although plants grown with the smaller containers showed greater water uptake, plant nutrient uptake was lower than with the larger container. All genotypes evaluated showed variation in their responses to all parameters measured.

  14. Nutrient load summaries for major lakes and estuaries of the Eastern United States, 2002

    USGS Publications Warehouse

    Moorman, Michelle C.; Hoos, Anne B.; Bricker, Suzanne B.; Moore, Richard B.; García, Ana María; Ator, Scott W.

    2014-01-01

    Nutrient enrichment of lakes and estuaries across the Nation is widespread. Nutrient enrichment can stimulate excessive plant and algal growth and cause a number of undesirable effects that impair aquatic life and recreational activities and can also result in economic effects. Understanding the amount of nutrients entering lakes and estuaries, the physical characteristics affecting the nutrient processing within these receiving waterbodies, and the natural and manmade sources of nutrients is fundamental to the development of effective nutrient reduction strategies. To improve this understanding, sources and stream transport of nutrients to 255 major lakes and 64 estuaries in the Eastern United States were estimated using Spatially Referenced Regression on Watershed attributes (SPARROW) nutrient models.

  15. Linkages between hydrogeomorphology and nutrient availability in wetlands (Invited)

    NASA Astrophysics Data System (ADS)

    Noe, G. B.; Hupp, C. R.; Schenk, E.; Batson, J.; Krauss, K.; Ensign, S.; Wolf, K.; Ahn, C.

    2013-12-01

    Hydrogeomorphology is an important determinant of nutrient transport, cycling, and availability in wetlands. Fluvial geomorphic position in the landscape can influence the connectivity of wetlands to flowing water, thereby affecting the inputs of nutrients to the wetland, and ultimately controlling biogeochemical transformations. Similarly, internal geomorphic heterogeneity (microtopography) can influence soil wetness within the wetland and biogeochemistry. Nitrogen (N) and phosphorus (P) inputs and soil biogeochemical transformations were measured across a range of wetland ecosystems, including floodplain wetlands, tidal freshwater wetlands, and created wetlands. Nitrogen and P inputs from sedimentation and inorganic ion loading to the soil surface were greater at locations with greater connectivity to river water. Nutrient inputs from sedimentation also vary across broad landscape gradients from nontidal, tidal freshwater, and tidal oligohaline wetlands. Both N and P mineralization in wetland soils increased with N and P inputs. Thus, greater hydrologic connectivity (as influenced by landscape position and river-wetland geomorphology) stimulates nutrient availability for primary production, other biogeochemical processes, and ecosystem nutrient retention. Furthermore, microtopographic heterogeneity within wetlands stimulated nutrient availability and retention. In tidal freshwater wetlands, hummocks were hotspots of soil nitrification relative to low lying hollows. In created wetlands, building microtopography during construction resulted in greater soil nitrification and denitrification. In conclusion, geomorphology and hydrology at multiple scales influence the inputs, biogeochemical transformations, and availability of nutrients in wetland ecosystems.

  16. Water and nutrient acquisition by roots and canopies

    SciTech Connect

    Oren, R.; Sheriff, D.W.

    1995-07-01

    Water and nutrient supply rates, as well as internal (plant) and external (soil) deficits, can have major effects on physiological activity and growth. Effects of water or nutrient deficits on growth can be demonstrated separately, but they often interact, as shown for several Pinus species, and by Turner (1982) for Pinus radiata. Moist soil and wet canopy surfaces facilitate nutrient uptake through roots and foliage, respectively. Water uptake is affected by the number and distribution of roots in relation to the distribution of soil moisture, and by the wetness and hydraulic permeability of foliage. Nutrient uptake is similarly affected by tissue characteristics and nutrient concentration, but also depends on the moisture regime in the bulk soil and in the vicinity of absorbing surfaces. In this chapter, we discuss generalities based on results from observational studies of unmanipulated plants and of stands. We also consider information from experimental manipulation of nutrient and water availability. A more thorough treatment of the effects of mycorrhizae and anthropogenic pollution on water and nutrient acquisition is given, respectively.

  17. Nutrient enrichment affects the mechanical resistance of aquatic plants

    PubMed Central

    Puijalon, Sara

    2012-01-01

    For many plant species, nutrient availability induces important anatomical responses, particularly the production of low-density tissues to the detriment of supporting tissues. Due to the contrasting biomechanical properties of plant tissues, these anatomical responses may induce important modifications in the biomechanical properties of plant organs. The aim of this study was to determine the effects of nutrient enrichment on the anatomical traits of two freshwater plant species and its consequences on plant biomechanical performance. Two plant species were grown under controlled conditions in low versus high nutrient levels. The anatomical and biomechanical traits of the plant stems were measured. Both species produced tissues with lower densities under nutrient-rich conditions, accompanied by modifications in the structure of the aerenchyma for one species. As expected, nutrient enrichment also led to important modifications in the biomechanical properties of the stem for both species. In particular, mechanical resistance (breaking force and strength) and stiffness of stems were significantly reduced under nutrient rich conditions. The production of weaker stem tissues as a result of nutrient enrichment may increase the risk of plants to mechanical failure, thus challenging plant maintenance in mechanically stressful or disturbed habitats. PMID:23028018

  18. The gastrointestinal tract as a nutrient-balancing organ

    PubMed Central

    Clissold, Fiona J.; Tedder, Benjamin J.; Conigrave, Arthur D.; Simpson, Stephen J.

    2010-01-01

    Failure to provision tissues with an appropriate balance of nutrients engenders fitness costs. Maintaining nutrient balance can be achieved by adjusting the selection and consumption of foods, but this may not be possible when the nutritional environment is limiting. Under such circumstances, rebalancing of an imbalanced nutrient intake requires post-ingestive mechanisms. The first stage at which such post-ingestive rebalancing might occur is within the gastrointestinal tract (GIT), by differential release of digestive enzymes—releasing less of those enzymes for nutrients present in excess while maintaining or boosting levels of enzymes for nutrients in deficit. Here, we use an insect herbivore, the locust, to show for the first time that such compensatory responses occur within the GIT. Furthermore, we show that differential release of proteases and carbohydrases in response to nutritional state translate into differential extraction of macronutrients from host plants. The prevailing view is that physiological and structural plasticity in the GIT serves to maximize the rate of nutrient gain in relation to costs of maintaining the GIT; our findings show that GIT plasticity is integral to the maintenance of nutrient balance. PMID:20129973

  19. Flavour-nutrient learning in humans: an elusive phenomenon?

    PubMed

    Yeomans, Martin R

    2012-06-01

    One widely cited model of how humans acquire liking for different foods is flavour-nutrient learning, where associations between the orosensory properties of the ingested food or drink (the flavour CS) and positive consequences of nutrient ingestion (the UCS) lead to acquired liking for the flavour (flavour-nutrient hedonic learning: FNL-H). Likewise, an association between the CS and the post-ingestive effects of ingested nutrients has been suggested to lead to learning about how satiating a particular food is (flavour-nutrient satiety learning: FNSH). However, whereas there is evidence for both FNL-H and FNL-S in experimental studies with non-human animals, evidence in humans is less convincing, with many failures to find the predicted changes in liking, preference or intake following repeated flavour-nutrient pairings. The present short review considers how subtle differences in experimental design might underlie this inconsistency, and identifies key design features which appear to increase the likelihood of success in human flavour-nutrient learning studies. Key factors include CS novelty, the level of nutrients ingested during training, the appetitive state of the consumer and individual consumer characteristics. A further complication is competition between FNL-H and FNL-S, and with other associations such as flavour-flavour learning. From this it is possible to make important inferences about the nature of human flavour-nutrient learning which firstly suggest that it has important similarities to that seen in other species, but secondly that the laboratory investigations of both FNL-H and FNL-S in humans can be compromised by subtle but important variations in experimental design. PMID:22465846

  20. Search the USDA National Nutrient Database for Standard Reference

    NSDL National Science Digital Library

    The USDA Agricultural Research Service Nutrient Data Laboratory presents the National Nutrient Database, which has an easy-to-search interface that quickly retrieves nutritional data for every food item that contains a specific keyword. For instance, searching for "soybean" calls up a long list of food items for which soybean is an ingredient: various margarines, salad dressings, and oils; raw soybeans; steamed soybeans; roasted soybeans; and so on. The complete nutrition report for each item can then be viewed after selecting a unit of measurement (e.g., per 100 grams). The database may also be search by single nutrients, such as iron or folic acid.

  1. Hydroponic Crop Production using Recycled Nutrients from Inedible Crop Residues

    NASA Technical Reports Server (NTRS)

    Garland, Jay L.; Mackowiak, Cheryl L.; Sager, John C.

    1993-01-01

    The coupling of plant growth and waste recycling systems is an important step toward the development of bioregenerative life support systems. This research examined the effectiveness of two alternative methods for recycling nutrients from the inedible fraction (residue) of candidate crops in a bioregenerative system as follows: (1) extraction in water, or leaching, and (2) combustion at 550 C, with subsequent reconstitution of the ash in acid. The effectiveness of the different methods was evaluated by (1) comparing the percent recovery of nutrients, and (2) measuring short- and long-term plant growth in hydroponic solutions, based on recycled nutrients.

  2. Placental nutrient supply and fetal growth.

    PubMed

    Desforges, Michelle; Sibley, Colin P

    2010-01-01

    This review considers mechanisms by which transfer across the placenta takes place and how the capacity of the placenta to supply nutrients relates to fetal growth and vice versa. Blood flow through both uterine and umbilical circulations of the placenta, the structural properties of the placental exchange barrier and its related diffusional permeability, and the expression and activity of a wide range of transporter proteins in the syncytiotrophoblast, the transporting epithelium of the placenta, all need to be taken into account in considering placental supply capacity. We discuss the evidence that each of these factors affects, and is affected by, fetal growth rate and consider the regulatory mechanisms involved, with a particular focus on data that has emerged from study of the system A amino acid transporter. We consider that future work will build on the considerable foundation of knowledge regarding placental transfer mechanisms, as well as the other aspects of placental structure and function, to develop new diagnostic and therapeutic strategies for pregnancy complications, such as fetal growth restriction or overgrowth. PMID:19876836

  3. The mycorrhizal-associated nutrient economy: a new framework for predicting carbon-nutrient couplings in temperate forests.

    PubMed

    Phillips, Richard P; Brzostek, Edward; Midgley, Meghan G

    2013-07-01

    Understanding the context dependence of ecosystem responses to global changes requires the development of new conceptual frameworks. Here we propose a framework for considering how tree species and their mycorrhizal associates differentially couple carbon (C) and nutrient cycles in temperate forests. Given that tree species predominantly associate with a single type of mycorrhizal fungi (arbuscular mycorrhizal (AM) fungi or ectomycorrhizal (ECM) fungi), and that the two types of fungi differ in their modes of nutrient acquisition, we hypothesize that the abundance of AM and ECM trees in a plot, stand, or region may provide an integrated index of biogeochemical transformations relevant to C cycling and nutrient retention. First, we describe how forest plots dominated by AM tree species have nutrient economies that differ in their C-nutrient couplings from those in plots dominated by ECM trees. Secondly, we demonstrate how the relative abundance of AM and ECM trees can be used to estimate nutrient dynamics across the landscape. Finally, we describe how our framework can be used to generate testable hypotheses about forest responses to global change factors, and how these dynamics can be used to develop better representations of plant-soil feedbacks and nutrient constraints on productivity in ecosystem and earth system models. PMID:23713553

  4. Porewater nutrient concentrations and benthic nutrient fluxes across the Pakistan margin OMZ

    NASA Astrophysics Data System (ADS)

    Woulds, Clare; Schwartz, Matthew C.; Brand, Tim; Cowie, Greg L.; Law, Gareth; Mowbray, Stephen R.

    2009-03-01

    Porewater concentrations and benthic fluxes of phosphate, silicate, ammonia, nitrate and nitrite were measured at five sites spanning the Pakistan margin oxygen minimum zone (OMZ), in order to characterise the biogeochemical processes occurring, and to assess whether oxygen concentration and a seasonal pulse of organic matter are controlling factors. Typical concentrations of 1-70 ?M, 50-250 ?M, 0-270 ?M, <5 ?M and 0-4 ?M for PO 43-, H 4SiO 4, NH 4+, NO 3- and NO 2-, respectively were obtained. Evidence was found for the occurrence of intense denitrification, sorption of PO 43- onto iron and manganese oxyhydroxides and possibly fluoroapatite precipitation at depth (>30 cm) in the sediment. These processes are all redox-sensitive, and their intensities varied across the margin, suggesting that oxygen concentration exerts a strong influence over nutrient concentrations and cycling. Variation in nutrient concentrations and fluxes before and after the summer monsoon was limited to an oxygen-driven change to the PO 43- profile at one site, indicating that either nutrient profiles do not generally alter on seasonal timescales, or that any impact of the monsoon had subsided before the post-monsoon sampling period. Porewater profile modelling tended to underestimate the magnitude of fluxes, but was in general agreement with the directions of measured fluxes, and in situ and shipboard flux measurements also generally agreed. Phosphate and H 4SiO 4 concentrations and benthic fluxes on the Pakistan margin were similar to those reported at abyssal sites from around the world, while NH 4+ and NO 3- concentrations and fluxes were comparable to shallower, more productive and/or hypoxic marine settings.

  5. LAKE ERIE NUTRIENT CONTROL: EFFECTIVENESS REGARDING ASSESSMENT IN EASTERN BASIN

    EPA Science Inventory

    A three-year synoptic monitoring program was conducted on 26 stations from 1973-75. Data generated included major nutrients, temperature structure and oxygen depletion as well as phytoplankton, zooplankton, and benthic macroinvertebrate dynamics....

  6. 9 CFR 381.463 - Nutrient content claims for “healthy.”

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...shall contain 10 percent or more of the Reference Daily Intake or Daily Reference Value as defined in § 381.409 for vitamin A, vitamin C, iron, calcium, protein, or fiber per reference amount customarily consumed prior to any nutrient...

  7. 9 CFR 381.463 - Nutrient content claims for “healthy.”

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...shall contain 10 percent or more of the Reference Daily Intake or Daily Reference Value as defined in § 381.409 for vitamin A, vitamin C, iron, calcium, protein, or fiber per reference amount customarily consumed prior to any nutrient...

  8. 9 CFR 381.463 - Nutrient content claims for “healthy.”

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...shall contain 10 percent or more of the Reference Daily Intake or Daily Reference Value as defined in § 381.409 for vitamin A, vitamin C, iron, calcium, protein, or fiber per reference amount customarily consumed prior to any nutrient...

  9. 9 CFR 317.363 - Nutrient content claims for “healthy.”

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...shall contain 10 percent or more of the Reference Daily Intake or Daily Reference Value as defined in § 317.309 for vitamin A, vitamin C, iron, calcium, protein, or fiber per reference amount customarily consumed prior to any nutrient...

  10. 9 CFR 317.363 - Nutrient content claims for “healthy.”

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...shall contain 10 percent or more of the Reference Daily Intake or Daily Reference Value as defined in § 317.309 for vitamin A, vitamin C, iron, calcium, protein, or fiber per reference amount customarily consumed prior to any nutrient...

  11. A Nutrient Combination that Can Affect Synapse Formation

    E-print Network

    Wurtman, Richard Jay

    Brain neurons form synapses throughout the life span. This process is initiated by neuronal depolarization, however the numbers of synapses thus formed depend on brain levels of three key nutrients—uridine, the omega-3 ...

  12. Evaluating nutrient impacts in urban watersheds: challenges and research opportunities.

    PubMed

    Carey, Richard O; Hochmuth, George J; Martinez, Christopher J; Boyer, Treavor H; Dukes, Michael D; Toor, Gurpal S; Cisar, John L

    2013-02-01

    This literature review focuses on the prevalence of nitrogen and phosphorus in urban environments and the complex relationships between land use and water quality. Extensive research in urban watersheds has broadened our knowledge about point and non-point pollutant sources, but the fate of nutrients is not completely understood. For example, it is not known how long-term nutrient cycling processes in turfgrass landscapes influence nitrogen retention rates or the relative atmospheric contribution to urban nitrogen exports. The effect of prolonged reclaimed water irrigation is also unknown. Stable isotopes have been used to trace pollutants, but distinguishing sources (e.g., fertilizers, wastewater, etc.) can be difficult. Identifying pollutant sources may aid our understanding of harmful algal blooms because the extent of the relationship between urban nutrient sources and algal blooms is unclear. Further research on the delivery and fate of nutrients within urban watersheds is needed to address manageable water quality impacts. PMID:23202644

  13. Herbivores and nutrients control grassland plant diversity via light limitation

    USGS Publications Warehouse

    Borer, Elizabeth T.; Seabloom, Eric W.; Gruner, Daniel S.; Harpole, W. Stanley; Hillebrand, Helmut; Lind, Eric M.; Alder, Peter B.; Alberti, Juan; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori; Blumenthal, Dana; Brown, Cynthia S.; Brudvig, Lars A.; Buckley, Yvonne M.; Cadotte, Marc; Chu, Cheng-Jin; Cleland, Elsa E.; Crawley, Michael J.; Daleo, Pedro; Damschen, Ellen I.; Davies, Kendi F.; DeCrappeo, Nicole M.; Du, Guozhen; Firn, Jennifer; Hautier, Yann; Heckman, Robert W.; Hector, Andy; HilleRisLambers, Janneke; Iribarne, Oscar; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Leakey, Andrew D.B.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Mortensen, Brent; O'Halloran, Lydia R.; Orrock, John L.; Pascual, Jesús; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Williams, Ryan J.; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

    2014-01-01

    Human alterations to nutrient cycles and herbivore communities are affecting global biodiversity dramatically. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  14. QUANTIFYING ASSAY VARIATION IN NUTRIENT ANALYSIS OF FEEDSTUFFS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analytical results from different laboratories have greater variation than those from a single laboratory, and this variation differs by nutrient. Objectives of this presentation are to describe methods for quantifying the analytical reproducibility among and repeatability within laboratories, estim...

  15. Act 38 Record Keeping Checklist Pennsylvania's Nutrient Management Plans

    E-print Network

    Guiltinan, Mark

    for each crop management unit _____ Land Application of Nutrients ­ annually; location (ID) & number of acres, date of application, and application rate for each crop management unit _____ Crop Yields ­ annually; approximate yield levels for each crop management unit _____ Uncollected Manure Information

  16. Gustatory and metabolic perception of nutrient stress in Drosophila.

    PubMed

    Linford, Nancy J; Ro, Jennifer; Chung, Brian Y; Pletcher, Scott D

    2015-02-24

    Sleep loss is an adaptive response to nutrient deprivation that alters behavior to maximize the chances of feeding before imminent death. Organisms must maintain systems for detecting the quality of the food source to resume healthy levels of sleep when the stress is alleviated. We determined that gustatory perception of sweetness is both necessary and sufficient to suppress starvation-induced sleep loss when animals encounter nutrient-poor food sources. We further find that blocking specific dopaminergic neurons phenocopies the absence of gustatory stimulation, suggesting a specific role for these neurons in transducing taste information to sleep centers in the brain. Finally, we show that gustatory perception is required for survival, specifically in a low nutrient environment. Overall, these results demonstrate an important role for gustatory perception when environmental food availability approaches zero and illustrate the interplay between sensory and metabolic perception of nutrient availability in regulating behavioral state. PMID:25675472

  17. Marsh Soil Responses to Nutrients: Belowground Structural and Organic Properties

    EPA Science Inventory

    Coastal marsh responses to nutrient enrichment apparently depend upon soil matrix and whether the system is primarily biogenic or minerogenic. Deteriorating organic rich marshes (Jamaica Bay, NY) receiving wastewater effluent had lower belowground biomass, organic matter, and soi...

  18. Marsh Soil Responses to Nutrients: Belowground Structural and Organic Properties.

    EPA Science Inventory

    Coastal marsh responses to nutrient enrichment apparently depend upon soil matrix and whether the system is primarily biogenic or minerogenic. Deteriorating organic rich marshes (Jamaica Bay, NY) receiving wastewater effluent had lower belowground biomass, organic matter, and soi...

  19. NUTRIENT LIMITATION AND PHOSPHATE REGENERATION IN ARTIFICIAL CUTAWAY

    E-print Network

    McCarthy, T.K.

    -chemical characteristics, trophic statuses and limiting nutrient states. Two of the alkaline mesotrophic study lakes were regenerated appeared to be independent of lake trophic status. The current data provide some evidence

  20. Design concept and experiment of ocean nutrient enhancer \\

    Microsoft Academic Search

    Kazuyuki Ouchi; H. Ohmura

    2004-01-01

    To increase a primary production in the sea, upwelling and discharging a Deep Ocean Water (DOW) which has very rich nutrient salts into the euphotic surface layer has been proposed by many oceanologists as a \\

  1. Nutrient load analysis of Lago de Yojoa, Honduras

    E-print Network

    Trate, Tia M. (Tia Marie)

    2006-01-01

    Lake Yojoa, Honduras is an important natural resource to the people of Honduras. The lake's water quality has been a controversial subject. This thesis describes a nutrient load analysis performed to gain a better understanding ...

  2. Nutrient cycling and plant dynamics in estuaries: A brief review

    NASA Astrophysics Data System (ADS)

    Flindt, Mogens R.; Pardal, Miguel Ângelo; Lillebø, Ana Isabel; Martins, Irene; Marques, João Carlos

    1999-07-01

    Eutrophication of European estuaries due to massive nutrient loading from urban areas and diffuse runoff from extensively cultivated land areas is analysed. Consequences for the ecology of estuaries, namely changes in plant species composition, which also affects heterotrophic organisms, are approached based on examples showing that the result is often a fundamental structural change of the ecosystem, from a grazing and/or nutrient controlled stable systems to unstable detritus/mineralisation systems, where the turnover of oxygen and nutrients is much more dynamic and oscillations between aerobic and anaerobic states frequently occur. Several relevant aspects are examined, namely the influence of rooted macrophytes on nutrient dynamics, by comparing bare bottom sediments with eelgrass covered sediments, primary production and the development of organic detritus, and hydrodynamics and its relations to the spatial distribution of macrophytes in estuarine systems.

  3. Nutrient composition and sensory properties of prepared ground beef

    E-print Network

    Bravo-Gutierrez, Maria Leticia

    1992-01-01

    NUTRIENT COMPOSITION AND SENSORY PROPERTIES OF PREPARED GROUND BEEF A Thesis by MARIA LETICIA BRAVO-GUTIERREZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1992 Major Subject: Food Science and Technology NUTRIENT COMPOSITION AND SENSORY PROPERTIES OF PREPARED GROUND BEEF A Thesis by Maria Leticia Bravo-Gutierrez Approved as to style and content by: Ki S. Rhee (Chair...

  4. Nutrient leaching characteristics of vegetation common to Texas reservoir sites

    E-print Network

    Weldon, Clark Pierce

    1975-01-01

    of leaching studies were conducted on representa- tive grasses, herbage and trees to determine the short term relative nutrient release rates of nitrogen and phos- phorous. Leaching studies were also perf'ormed to deter- mine the eff'ects, if any, of... release was found to vary widely depending upon vegetation type, tissue type, decom- position state, and aeration. As an example, nutrients were released from grasses at a much faster rate than from tree leaves, bark, or twigs. This indicates...

  5. Swift recovery of Sphagnum nutrient concentrations after excess supply.

    PubMed

    Limpens, Juul; Heijmans, Monique M P D

    2008-08-01

    Although numerous studies have addressed the effects of increased N deposition on nutrient-poor environments such as raised bogs, few studies have dealt with to what extent, and on what time-scale, reductions in atmospheric N supply would lead to recovery of the ecosystems in question. Since a considerable part of the negative effects of elevated N deposition on raised bogs can be related to an imbalance in tissue nutrient concentrations of the dominant peat-former Sphagnum, changes in Sphagnum nutrient concentration after excess N supply may be used as an early indicator of ecosystem response. This study focuses on the N and P concentrations of Sphagnum magellanicum and Sphagnum fallax before, during and after a factorial fertilization experiment with N and P in two small peatlands subject to a background bulk deposition of 2 g N m(-2) year(-1). Three years of adding N (4.0 g N m(-2) year(-1)) increased the N concentration, and adding P (0.3 g P m(-2) year(-1)) increased the P concentration in Sphagnum relative to the control treatment at both sites. Fifteen months after the nutrient additions had ceased, N concentrations were similar to the control whereas P concentrations, although strongly reduced, were still slightly elevated. The changes in the N and P concentrations were accompanied by changes in the distribution of nutrients over the capitulum and the stem and were congruent with changes in translocation. Adding N reduced the stem P concentration, whereas adding P reduced the stem N concentration in favor of the capitulum. Sphagnum nutrient concentrations quickly respond to reductions in excess nutrient supply, indicating that a management policy aimed at reducing atmospheric nutrient input to bogs can yield results within a few years. PMID:18465147

  6. Managing Crop Nutrients Through Soil, Manure and Effluent Testing 

    E-print Network

    McFarland, Mark L.; Provin, Tony; Feagley, Sam E.

    1998-12-10

    and manures contain smaller amounts of other plant nutrients including calci- um, magnesium, sulfur, manganese, copper, iron, zinc, boron, molybde- num, and chloride. Along with these nutrients, manures and litters supply valuable organic matter to help... Received: Date Reported: County: Plant Analysis* Plant Analysis Ratings Lab Sample ID Nitrogen Phosphorus Potassium Calcium Magnesium Sodium Zinc Iron Copper Manganese Sulfur Boron Number Sample Type % % % % % PPM PPM PPM PPM PPM PPM PPM xxx...

  7. Inventory of nutrient compounds in the Yellow Sea

    Microsoft Academic Search

    S. M Liu; J Zhang; S. Z Chen; H. T Chen; G. H Hong; H Wei; Q. M Wu

    2003-01-01

    Nutrient species were analyzed from samples collected in the Yellow Sea in May 1998, including NO3?, NO2?, NH4+, PO43?, SiO32?, dissolved organic nitrogen (DON), particulate nitrogen, dissolved organic phosphorus (DOP), particulate phosphorus, etc. The exchange fluxes of nutrients across the sediment\\/water interface were determined by incubation of sediment on board the ship. The concentrations of N, P and Si compounds

  8. Upper Mississippi Basin Loading Database (Sediment and Nutrients): Update

    NSDL National Science Digital Library

    The Upper Midwest Environmental Sciences Center (UMESC) provides this updated database on sediments and nutrients of the Upper Mississippi River Basin. Included in the database are maps (Shape) showing the locations of monitoring stations; figures displaying rates of Nitrogen/ Phosphorus loadings and yields; and sediment and nutrient data by sub-area (ascii, .xls, Lotus). In addition, background information is provided on the monitoring sites.

  9. Dynamics of inorganic nutrient species in the Bohai seawaters

    Microsoft Academic Search

    J. Zhang; Z. G Yu; T Raabe; S. M Liu; A Starke; L Zou; H. W Gao; U Brockmann

    2004-01-01

    Within the frame of a Sino-German Joint Research Program, two cruises of “R\\/V Dong Fang Hong 2” were carried out in September–October 1998 and April–May 1999, respectively, to understand the dynamics of nutrients in the Bohai. Nutrient species (NO3?, NO2?, NH4+, PO43? and SiO32?) are determined colorimetrically on board for five anchor and 30 grid stations. In situ incubation experiments

  10. Distributions of inorganic nutrients in the bohai sea of china

    Microsoft Academic Search

    Li Zhengyan; Bai Jie; Shi Jinhui; Gao Huiwang

    2003-01-01

    To study the contents and distribution of inorganic nutrients in the Bohai Sea of China, two cruise surveys were undertaken\\u000a in August (summer) 2000 and January (winter) 2001, respectively. A total of 595 water samples were collected from 91 stations\\u000a and five nutrients, i.e., nitrate, nitrite, ammonia, phosphate and silicate, were analyzed for each sample. The results show that the

  11. Nutrient Transport into the White Sea with River Runoff

    Microsoft Academic Search

    A. V. Leonov; O. V. Chicherina

    2004-01-01

    Averaged data from long-term observations of concentrations of mineral-nutrient fractions along with fragmentary data and indirect estimates of organic-component concentrations in the tributaries of the sea (the Niva, the Onega, the Northern Dvina, the Mezen, and the Kem rivers) are analyzed. Monthly variations in the concentrations of the major nutrients in the river water flowing into the sea are characterized,

  12. Effects of mountain agriculture on nutrient cycling at upstream watersheds

    NASA Astrophysics Data System (ADS)

    Lin, T.-C.; Shaner, P. L.; Wang, L.-J.; Shih, Y.-T.; Wang, C.-P.; Huang, G.-H.; Huang, J.-C.

    2015-05-01

    The expansion of agriculture to rugged mountains can exacerbate negative impacts of agriculture activities on ecosystem function. In this study, we monitored streamwater chemistry of four watersheds with varying proportions of agricultural lands (0.4, 3, 17, 22%) and rainfall chemistry of two of the four watersheds at Feitsui Reservoir Watershed in northern Taiwan to examine the effects of agriculture on watershed nutrient cycling. We found that the greater the proportions of agricultural lands, the higher the ion concentrations, which is evident for fertilizer-associated ions (NO3-, K+) but not for ions that are rich in soils (SO42-, Ca2+, Mg2+), suggesting that agriculture enriched fertilizer-associated nutrients in streamwater. The watershed with the highest proportion of agricultural lands had higher concentrations of ions in rainfall and lower nutrient retention capacity (i.e. higher output-input ratio of ions) compared to the relatively pristine watershed, suggesting that agriculture can influence atmospheric deposition of nutrients and a system's ability to retain nutrients. Furthermore, we found that a forested watershed downstream of agricultural activities can dilute the concentrations of fertilizer-associated ions (NO3-, K+) in streamwater by more than 70%, indicating that specific landscape configurations help mitigate nutrient enrichment to aquatic systems. We estimated that agricultural lands at our study site contributed approximately 400 kg ha-1 yr-1 of NO3-N and 260 kg ha-1 yr-1 of PO4-P output via streamwater, an order of magnitude greater than previously reported around the globe and can only be matched by areas under intense fertilizer use. Furthermore, we re-constructed watershed nutrient fluxes to show that excessive leaching of N and P, and additional loss of N to the atmosphere via volatilization and denitrification, can occur under intense fertilizer use. In summary, this study demonstrated the pervasive impacts of agriculture activities, especially excessive fertilization, on ecosystem nutrient cycling at mountain watersheds.

  13. Nutrient mobility in variable- and permanent-charge soils

    Microsoft Academic Search

    Phillip Sollins; G. PHILIP ROBERTSON; Goro Uehara

    1988-01-01

    Variable-charge (v-c) and permanent-charge (p-c) soils differ fundamentally with regard to many nutrient-cycling processes. Variable-charge soils are more common in the tropics than in temperature zones because their formation requires desilication, which proceeds fastest in warm, moist climates. The dynamics of nutrient mobility tend to be more complex in v-c than in p-c soils. For example, theory predicts that, as

  14. Swift recovery of Sphagnum nutrient concentrations after excess supply

    PubMed Central

    Heijmans, Monique M. P. D.

    2008-01-01

    Although numerous studies have addressed the effects of increased N deposition on nutrient-poor environments such as raised bogs, few studies have dealt with to what extent, and on what time-scale, reductions in atmospheric N supply would lead to recovery of the ecosystems in question. Since a considerable part of the negative effects of elevated N deposition on raised bogs can be related to an imbalance in tissue nutrient concentrations of the dominant peat-former Sphagnum, changes in Sphagnum nutrient concentration after excess N supply may be used as an early indicator of ecosystem response. This study focuses on the N and P concentrations of Sphagnum magellanicum and Sphagnum fallax before, during and after a factorial fertilization experiment with N and P in two small peatlands subject to a background bulk deposition of 2 g N m?2 year?1. Three years of adding N (4.0 g N m?2 year?1) increased the N concentration, and adding P (0.3 g P m?2 year?1) increased the P concentration in Sphagnum relative to the control treatment at both sites. Fifteen months after the nutrient additions had ceased, N concentrations were similar to the control whereas P concentrations, although strongly reduced, were still slightly elevated. The changes in the N and P concentrations were accompanied by changes in the distribution of nutrients over the capitulum and the stem and were congruent with changes in translocation. Adding N reduced the stem P concentration, whereas adding P reduced the stem N concentration in favor of the capitulum. Sphagnum nutrient concentrations quickly respond to reductions in excess nutrient supply, indicating that a management policy aimed at reducing atmospheric nutrient input to bogs can yield results within a few years. PMID:18465147

  15. Response of shallow aquatic ecosystems to different nutrient loading levels

    Microsoft Academic Search

    R. Portielje

    1994-01-01

    Eutrophication of surface waters leads to a decline of water quality, which becomes manifest as an impoverishment of the aquatic community. Insight into the effects of eutrophication on the structure and functioning of these communities and knowlegde on underlying interactions is needed to quantify the required reduction of nutrient input.<\\/TT>To investigate the effects of nutrient loading on the receiving water,

  16. Long-term nutrient enrichment decouples predator and prey production

    PubMed Central

    Davis, John M.; Rosemond, Amy D.; Eggert, Susan L.; Cross, Wyatt F.; Wallace, J. Bruce

    2009-01-01

    Increased nutrient mobilization by human activities represents one of the greatest threats to global ecosystems, but its effects on ecosystem productivity can differ depending on food web structure. When this structure facilitates efficient energy transfers to higher trophic levels, evidence from previous large-scale enrichments suggests that nutrients can stimulate the production of multiple trophic levels. Here we report results from a 5-year continuous nutrient enrichment of a forested stream that increased primary consumer production, but not predator production. Because of strong positive correlations between predator and prey production (evidence of highly efficient trophic transfers) under reference conditions, we originally predicted that nutrient enrichment would stimulate energy flow to higher trophic levels. However, enrichment decoupled this strong positive correlation and produced a nonlinear relationship between predator and prey production. By increasing the dominance of large-bodied predator-resistant prey, nutrient enrichment truncated energy flow to predators and reduced food web efficiency. This unexpected decline in food web efficiency indicates that nutrient enrichment, a ubiquitous threat to aquatic ecosystems, may have unforeseen and unpredictable effects on ecosystem structure and productivity. PMID:20018677

  17. Potato growth and yield using nutrient film technique (NFT).

    PubMed

    Wheeler, R M; Mackowiak, C L; Sager, J C; Knott, W M; Hinkle, C R

    1990-01-01

    Potato plants, cvs Denali and Norland, were grown in polyvinyl chloride (PVC) trays using a continuous flowing nutrient film technique (NFT) to study tuber yield for NASA's Controlled Ecological Life Support Systems (CELSS) program. Nutrient solution pH was controlled automatically using 0.39M (2.5% (v/v) nitric acid (HNO3), while water and nutrients were replenished manually each day and twice each week, respectively. Plants were spaced either one or two per tray, allotting 0.2 or 0.4 m2 per plant. All plants were harvested after 112 days. Denali plants yielded 2850 and 2800 g tuber fresh weight from the one- and two-plant trays, respectively, while Norland plants yielded 1800 and 2400 g tuber fresh weight from the one- and two-plant trays. Many tubers of both cultivars showed injury to the periderm tissue, possibly caused by salt accumulation from the nutrient solution on the surface. Total system water usage throughout the study for all the plants equaled 709 liters (L), or approximately 2 L m-2 d-1. Total system acid usage throughout the study (for nutrient solution pH control) equaled 6.60 L, or 18.4 ml m-2 d-1 (7.2 mmol m-2 d-1). The results demonstrate that continuous flowing nutrient film technique can be used for tuber production with acceptable yields for the CELSS program. PMID:11537254

  18. Substrate and nutrient limitation regulating microbial growth in soil

    NASA Astrophysics Data System (ADS)

    Bååth, Erland

    2015-04-01

    Microbial activity and growth in soil is regulated by several abiotic factors, including temperature, moisture and pH as the most important ones. At the same time nutrient conditions and substrate availability will also determine microbial growth. Amount of substrate will not only affect overall microbial growth, but also affect the balance of fungal and bacterial growth. The type of substrate will also affect the latter. Furthermore, according to Liebig law of limiting factors, we would expect one nutrient to be the main limiting one for microbial growth in soil. When this nutrient is added, the initial second liming factor will become the main one, adding complexity to the microbial response after adding different substrates. I will initially describe different ways of determining limiting factors for bacterial growth in soil, especially a rapid method estimating bacterial growth, using the leucine incorporation technique, after adding C (as glucose), N (as ammonium nitrate) and P (as phosphate). Scenarios of different limitations will be covered, with the bacterial growth response compared with fungal growth and total activity (respiration). The "degree of limitation", as well as the main limiting nutrient, can be altered by adding substrate of different stoichiometric composition. However, the organism group responding after alleviating the nutrient limitation can differ depending on the type of substrate added. There will also be situations, where fungi and bacteria appear to be limited by different nutrients. Finally, I will describe interactions between abiotic factors and the response of the soil microbiota to alleviation of limiting factors.

  19. [Compare the growth of Enteromorpha prolifera under different nutrient conditions].

    PubMed

    Pang, Qiu-ting; Li, Feng; Liu, Xiang-qing; Wang, Jiang-tao

    2013-09-01

    Enteromorpha prolifera (E. prolifera) tides have erupted frequently in the Yellow Sea and brought serious environmental problems to coastal sea since 2007. In order to research the influence of nutrients on E. prolifera growth, mesocosm experiments were carried out in the Yellow Sea in May 2012. There were 12 mesocosms, including 9 different experimental conditions. It shows that the uptake ability of nutrients and the growth of E. prolifera are strong. The growth rate of E. prolifera reaches 82% when the nutrient level is appropriate, while the rate could also keep around 10% even under low nutrient conditions. When phosphate level is appropriate, high dissolved inorganic nitrogen (DIN) concentration could promote the growth of E. prolifera. Sufficient and continuous nutrient supplement is the material basis for outbreak of E. prolifera green tide. Through analyzing the amount of nutrient uptake by E. prolifera, the production of organics by photosynthesis could be estimated, which has a strong linear relationship with the increased of wet weight of E. prolifera. PMID:24288982

  20. Insights into digestion and absorption of major nutrients in humans

    NSDL National Science Digital Library

    Barbara E. Goodman (Sanford School of Medicine, University of South Dakota Basic Biomedical Sciences)

    2010-06-01

    Nutrient digestion and absorption is necessary for the survival of living organisms and has evolved into the complex and specific task of the gastrointestinal (GI) system. While most people simply assume that their GI tract will work properly to use nutrients, provide energy, and release wastes, few non-scientists know the details about how various nutrients are digested and how the breakdown products traverse the cells lining the small intestine to reach the blood stream and to be used by the other cells of the body. There have been several recent discoveries of new transporters that likely contribute to the absorption of oligopeptides and fatty acids. In addition, details are being clarified about how transporters work and in what forms nutrients can be absorbed. The enzymes that digest basic carbohydrates, proteins, and fats have been identified in various segments of the GI tract, and details are becoming clearer about what types of bonds they hydrolyze. Usually, detailed information about the digestion of basic nutrients is presented and learned in biochemistry courses and detailed information about absorption via transepithelial transport of the breakdown products of digestion is studied in physiology courses. The goal of this Staying Current article is to combine the details of the biochemistry of digestion with the updated information about the physiology of nutrient absorption into one source for teachers of physiology. Insights are included about some of the diseases and conditions that can bring about malabsorption of food in the GI tract and their consequences.

  1. A global model of carbon-nutrient interactions

    NASA Technical Reports Server (NTRS)

    Moore, Berrien, III; Gildea, Patricia; Vorosmarty, Charles; Mellilo, Jerry M.; Peterson, Bruce J.

    1985-01-01

    The global biogeochemical model presented has two primary objectives. First, it characterizes natural elemental cycles and their linkages for the four elements significant to Earth's biota: C, N, S, and P. Second, it describes changes in these cycles due to human activity. Global nutrient cycles were studied within the drainage basins of several major world rivers on each continent. The initial study region was the Mississippi drainage basin, concentrating on carbon and nitrogen. The model first establishes the nutrient budgets of the undisturbed ecosystems in a study region. It then uses a data set of land use histories for that region to document the changes in these budgets due to land uses. Nutrient movement was followed over time (1800 to 1980) for 30 ecosystems and 10 land use categories. A geographically referenced ecological information system (GREIS) was developed to manage the digital global data bases of 0.5 x 0.5 grid cells needed to run the model: potential vegetation, drainage basins, precipitation, runoff, contemporary land cover, and FAO soil maps of the world. The results show the contributions of land use categories to river nutrient loads on a continental scale; shifts in nutrient cycling patterns from closed, steady state systems to mobile transient or open, steady state systems; soil organic matter depletion patterns in U.S. agricultural lands; changing nutrient ratios due to land use changes; and the effect of using heavy fertilizer on aquatic systems.

  2. Status of selected nutrients in obese dogs undergoing caloric restriction

    PubMed Central

    2013-01-01

    Background The purpose of this study was to test the hypothesis that dog plasma concentrations of selected nutrients decrease after undergoing caloric restriction for weight loss. Thirty-one overweight dogs that had successfully lost at least 15% of initial body weight were included in the study. Nutrients that had been previously identified to be at potential risk of deficiency during caloric restriction were measured in plasma (choline, amino acids) and urine (selenium) at the initiation and completion of a standardized weight loss regimen in dogs. Results Dogs remained healthy throughout the study, and no signs attributable to nutrient deficiency were noted. Percentage weight loss was 28.3% (16.0-40.1%) starting body weight, over a period of 250 days (91–674 days). Median energy intake during the weight loss period was 62 (44 to 74) Kcal/kg0.75 target weight per day. Choline (P?=?0.046) and threonine (P?=?0.02) decreased after weight loss. Glycine (P?=?0.041), and urinary selenium:creatinine ratio (P?=?0.006) both increased after weight loss. There were no other significant differences in plasma nutrient concentrations. Conclusions Since concentrations of most measured nutrients did not change significantly, the data are not consistent with widespread nutrient deficiency in dogs undergoing caloric restriction using a diet formulated for weight loss. However, the significance of the decrease in plasma choline concentration requires further assessment. PMID:24156605

  3. Controlled environments alter nutrient content of soybeans.

    PubMed

    Jurgonski, L J; Smart, D J; Bugbee, B; Nielsen, S S

    1997-01-01

    Information about compositional changes in plants grown in controlled environments is essential for developing a safe, nutritious diet for a Controlled Ecomological Life-Support System (CELSS). Information now is available for some CELSS candidate crops, but detailed information has been lacking for soybeans. To determine the effect of environment on macronutrient and mineral composition of soybeans, plants were grown both in the field and in a controlled environment where the hydroponic nutrient solution, photosynthetic flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at seed maturity, separated into discrete parts, and oven dried prior to chemical analysis. Plant material was analyzed for proximate composition (moisture, protein, lipid, ash, and carbohydrate), total nitrogen (N), nonprotein N (NPN), nitrate, minerals, amino acid composition, and total dietary fiber. The effect of environment on composition varied by cultivar and plant part. Chamber-grown plants generally exhibited the following characteristics compared with field-grown plants: 1) increased total N and protein N for all plant parts, 2) increased nitrate in leaves and stems but not in seeds, 3) increased lipids in seeds, and 4) decreased Ca:P ratio for stems, pods, and leaves. These trends are consistent with data for other CELSS crops. Total N, protein N, and amino acid contents for 350 ppm CO2 and 1000 ppm CO2 were similar for seeds, but protein N and amino acid contents for leaves were higher at 350 ppm CO2 than at 1000 ppm CO2. Total dietary fiber content of soybean leaves was higher with 350 ppm CO2 than with 1000 ppm CO2. Such data will help in selecting of crop species, cultivars, and growing conditions to ensure safe, nutritious diets for CELSS. PMID:11542579

  4. The impact of large animal extinctions on nutrient fluxes in early river valley civilizations

    E-print Network

    Malhi, Yadvinder

    this changing nutrient flux using a ``random walk'' model and estimate that phosphorus (P) concentrations of nutrients away from nutrient concentration gradients common near floodplains, and the local extinction of nutrient concentration gradients, with the largest animals dispropor- tionally important in this transport

  5. Methods of Imputation used in the USDA National Nutrient Database for Standard Reference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: To present the predominate methods of imputing used to estimate nutrient values for foods in the USDA National Nutrient Database for Standard Reference (SR20). Materials and Methods: The USDA Nutrient Data Laboratory developed standard methods for imputing nutrient values for foods wh...

  6. Budgets of non-nitrogen nutrients in a high fertility pasture system

    Microsoft Academic Search

    L. B Owens; R. W Van Keuren; W M. Edwards

    1998-01-01

    Concentrations and transport of non-nitrogen nutrients in surface runoff and subsurface flow were determined under a high fertility pasture system during a multi-year study. Most studies of nutrient loss from grasslands have focused solely or primarily on nitrogen. Nevertheless, maintaining a proper balance of other nutrients is important to healthy plant growth, avoidance of toxicity problems from improper nutrient balances,

  7. Establishing Relationships Among Nutrient Concentrations, Phytoplankton Abundance, and Biochemical Oxygen Demand in Minnesota, USA, Rivers

    Microsoft Academic Search

    Steven Heiskary; Howard Markus

    2001-01-01

    In this study, we demonstrated significant and predictable relationships among nutrients, algae, and biochemical oxygen demand (BOD) in five medium to large Minnesota, USA, rivers. These rivers were distributed across three ecoregions ranging from the Northern Lakes & Forests (NLF) (low nutrients), to the North Central Hardwood forests (NCHF) (intermediate nutrients), to the Western Corn Belt Plains (WCBP) (high nutrients).

  8. Testing nutrient profile models in relation to energy density and energy cost

    Microsoft Academic Search

    A Drewnowski; M Maillot; N Darmon

    2009-01-01

    Background: Nutrient profiling of foods is defined as the science of classifying foods based on their nutrient content. Food rankings generated by nutrient profile models need to be tested against objective reality as opposed to public opinion.Objective: To test the performance of selected nutrient profile models in relation to the foods' energy density (kcal g?1) and energy cost (Dollar per

  9. Biomass and nutrient removal by willow clones in experimental bioenergy plantations in New York State

    Microsoft Academic Search

    Hector G. Adegbidi; Timothy A. Volk; Edwin H. White; Lawrence P. Abrahamson; Russell D. Briggs; Donald H. Bickelhaupt

    2001-01-01

    The development of short-rotation intensive cultural (SRIC) willow systems as a source of bioenergy and bioproducts is growing in the northeastern and midwestern United States. Important data for sustainable management such as nutrient removal and nutrient use efficiency in willow bioenergy plantations is lacking. This study reports wood biomass production, annual removal of nutrients, and nutrient use efficiency in experimental

  10. Modelling of Usual Nutrient Intakes: Potential Impact of the Choices Programme on Nutrient Intakes in Young Dutch Adults

    PubMed Central

    Roodenburg, Annet J. C.; van Ballegooijen, Adriana J.; Dötsch-Klerk, Mariska; van der Voet, Hilko; Seidell, Jacob C.

    2013-01-01

    Introduction The Choices Programme is an internationally applicable nutrient profiling system with nutrition criteria for trans fatty acids (TFA), saturated fatty acids, sodium, added sugar and for some product groups energy and fibre. These criteria determine whether foods are eligible to carry a “healthier option” stamp. In this paper a nutrient intake modelling method is described to evaluate these nutritional criteria by investigating the potential effect on nutrient intakes. Methods Data were combined from the 2003 Dutch food consumption survey in young adults (aged 19–30) and the Dutch food composition table into the Monte Carlo Risk Assessment model. Three scenarios were calculated: the “actual intakes” (scenario 1) were compared to scenario 2, where all foods that did not comply were replaced by similar foods that did comply with the Choices criteria. Scenario 3 was the same as scenario 2 adjusted for the difference in energy density between the original and replacement food. Additional scenarios were calculated where snacks were not or partially replaced and stratified analyses for gender, age, Body Mass Index (BMI) and education. Results Calculated intake distributions showed that median energy intake was reduced by 16% by replacing normally consumed foods with Choices compliant foods. Intakes of nutrients with a maximal intake limit were also reduced (ranging from ?23% for sodium and ?62% for TFA). Effects on intakes of beneficial nutrients varied from an unintentional reduction in fat soluble vitamin intakes (?15 to ?28%) to an increase of 28% for fibre and 17% calcium. Stratified analyses in this homogeneous study population showed only small differences across gender, age, BMI and education. Conclusions This intake modelling method showed that with consumption of Choices compliant foods, nutrient intakes shift towards population intake goals for the nutrients for which nutrition criteria were defined, while effects on beneficial nutrients were diverse. PMID:24015237

  11. Sources of nutrients impacting surface waters in Florida: a review.

    PubMed

    Badruzzaman, Mohammad; Pinzon, Jimena; Oppenheimer, Joan; Jacangelo, Joseph G

    2012-10-30

    The promulgation of numeric nutrient criteria for evaluating impairment of waterbodies in Florida is underway. Adherence to the water quality standards needed to meet these criteria will potentially require substantial allocations of public and private resources in order to better control nutrient (i.e., nitrogen and phosphorus) releases from contributing sources. Major sources of nutrients include atmospheric deposition (195-380 mg-N/m(2)/yr, 6 to 16 mg-P/m(2)/yr), reclaimed water irrigation (0.13-29 mg-N/L, 0.02 to 6 mg-P/L), septic systems (3.3 × 10(3)-6.68 × 10(3) g-N/person/yr, 0.49 × 10(3)-0.85 × 10(3) g-P/person/yr) and fertilizer applications (8 × 10(6)-24 × 10(6) mg-N/m(2)/yr). Estimated nitrogen loadings to the Florida environment, as calculated from the above rates are as follows: 5.9 × 10(9)-9.4 × 10(9) g-N/yr from atmospheric deposition, 1.2 × 10(8)-2.6 × 10(10) g-N/yr from reclaimed water, 2.4 × 10(10)-4.9 × 10(10) g-N/year from septic systems, and 1.4 × 10(11) g-N/yr from fertilizer application. Similarly, source specific phosphorus loading calculations are also presented in this paper. A fraction of those nutrient inputs may reach receiving waterbodies depending upon site specific regulation on nutrient control, nutrient management practices, and environmental attenuation. In Florida, the interconnectivity of hydrologic pathways due to the karst landscape and high volumes of rainfall add to the complexity of tracking nutrient loads back to their sources. In addition to source specific nutrient loadings, this review discusses the merits of source specific markers such as elemental isotopes (boron, nitrogen, oxygen, strontium, uranium and carbon) and trace organic compounds (sucralose, gadolinium anomaly, carbamazepine, and galaxolide) in relating nutrient loads back to sources of origin. Although this review is focused in Florida, the development of source specific markers as a tool for tracing nutrient loadings back to sources of origin is applicable and of value to all other geographical locations. PMID:22699026

  12. Changes in the nutrient ratios and phytoplankton community after declines in nutrient concentrations in a semi-enclosed bay in Hong Kong.

    PubMed

    Lie, Alle A Y; Wong, C Kim; Lam, Jackie Y C; Liu, J H; Yung, Y K

    2011-04-01

    Tolo Harbour is a landlocked bay with poor tidal flushings in the northeastern part of Hong Kong. During the 1980s, excessive nutrient loading led to dramatic increase in nutrient concentrations, accompanied by lower N:P ratios, higher algal biomass and shifts in the phytoplankton community. We studied the effects of nutrient loading reduction measures on nutrient concentrations, nutrient ratios and phytoplankton dynamics in Tolo Harbour by comparing data collected before the full implementation of nutrient loading reduction measures (1986-1997) to those after the implementation (1998-2008). Such measures led to declines in nutrient concentrations, changes in N:P and N:Si ratios, lower chlorophyll-a concentrations and fewer algal blooms. Diatoms were the most abundant phytoplankton group in Tolo Harbour both before and after declines in nutrient concentrations. The density of dinoflagellates did not change, but substantial increase in other algal group abundance was recorded. PMID:21316754

  13. A COMPARATIVE ANALYSIS OF NUTRIENT LOADING, NUTRIENT RETENTION AND NET ECOSYSTEM METABOLISM IN THREE TIDAL RIVER ESTUARIES DIFFERING PREDOMINATELY BY THEIR WATERSHED LAND USE TYPES.

    EPA Science Inventory

    Abstract and oral presentation for the Estuarine Research Federation Conference. Estuarine retention of watershed nutrient loads, system-wide nutrient biogeochemical fluxes, and net ecosystem metabolism (NEM) were determined in three estuaries exhibiting differing magnitud...

  14. Arbuscular mycorrhiza in relation to management history, soil nutrients and plant species diversity

    Microsoft Academic Search

    Åsa Eriksson

    2001-01-01

    Thelow nutrient status of semi-natural grasslands, pastures and meadows,reflects a continuity of nutrient reduction by grazing and hay-making. Ithas been hypothesized that the nutrient depletion itself may reduce competitionbetween individuals, and that mycorrhiza smooths out differences in nutrientuptake and competitive ability, so that competition for nutrients is evenfurther reduced. This interaction between site history, nutrient status andmycorrhiza could thus be

  15. Differences in egg nutrient availability, development, and nutrient metabolism of broiler and layer embryos.

    PubMed

    Nangsuay, A; Molenaar, R; Meijerhof, R; van den Anker, I; Heetkamp, M J W; Kemp, B; van den Brand, H

    2015-03-01

    Selection for production traits of broilers and layers leads to physiological differences, which may already be present during incubation. This study aimed to investigate the influence of strain (broiler vs layer) on egg nutrient availability, embryonic development and nutrient metabolism. A total of 480 eggs with an egg weight range of 62.0 to 64.0 g from Lohmann Brown Lite and Ross 308 breeder flocks of 41 or 42 weeks of age were selected in two batches of 120 eggs per batch per strain. For each batch, 30 eggs per strain were used to determine egg composition, including nutrient and energy content, and 90 eggs per strain were separately incubated in one of two climate respiration chambers at an eggshell temperature of 37.8°C. The results showed that broiler eggs had a higher ratio of yolk: albumen with 2.41 g more yolk and 1.48 g less albumen than layers. The yolk energy content of broiler eggs was 46.32 kJ higher than that of layer eggs, whereas total energy content of broiler eggs was 47.85 kJ higher compared to layer eggs. Yolk-free body mass at incubation day 16 and chick weight and length at hatch were higher in broilers compared to layers. Respiration quotient of broiler embryos was higher than layer embryos during incubation day 8 to incubation day 10. A 0.24 g lower residual yolk at the hatch of broiler embryos than for the layer embryos indicated that broiler embryos used more yolk and had a higher energy utilization and energy deposition in yolk-free body mass. Heat production of broiler embryos was higher than that of layer embryos from incubation day 12 to incubation day 18, but efficiency of converting egg energy used by embryos to form yolk-free body mass was similar. In conclusion, broiler and layer embryos have different embryonic development patterns, which affect energy utilization and embryonic heat production. However, the embryos are equal in efficiency of converting the energy used to yolk-free body mass. PMID:25700914

  16. Long-term biomass production and nutrient uptake of birch, alder and willow plantations on cut-away peatland

    Microsoft Academic Search

    Jyrki Hytönen; Anna Saarsalmi

    2009-01-01

    The leafless above-ground biomass production of planted silver birch (Betula pendula), downy birch (Betula pubescens), grey alder (Alnus incana), indigenous willows (Salix triandra and Salix phylicifolia) and an alder-willow mixture growing on a cut-away peatland area in Central Finland was investigated during a period of 18 (willows) or 19 (birches and alders) years. Biannual fertilization of the birches (0, NPK)

  17. Modeling the Response of Cassava to Fertilizers: A Site-Specific Nutrient Management Approach for Greater Tuberous Root Yield

    Microsoft Academic Search

    G. Byju; M. Nedunchezhiyan; C. S. Ravindran; V. S. Santhosh Mithra; V. Ravi; S. K. Naskar

    2012-01-01

    Conventional fertilizer-management strategy results in decreased fertilizer-use efficiency and unbalanced nitrogen (N)–phosphorus (P)–potassium (K) applications. The quantitative evaluation of fertility of tropical soils (QUEFTS) model was used for determining region-specific balanced NPK uptake requirements and recommendations for a target yield of cassava. Minimum and maximum internal efficiencies of N, P, and K were estimated as 35 and 80 for N,

  18. Distributions of inorganic nutrients in the bohai sea of china

    NASA Astrophysics Data System (ADS)

    Zhengyan, Li; Jie, Bai; Jinhui, Shi; Huiwang, Gao

    2003-04-01

    To study the contents and distribution of inorganic nutrients in the Bohai Sea of China, two cruise surveys were undertaken in August (summer) 2000 and January (winter) 2001, respectively. A total of 595 water samples were collected from 91 stations and five nutrients, i.e., nitrate, nitrite, ammonia, phosphate and silicate, were analyzed for each sample. The results show that the average concentration of dissolved inorganic nitrogen (DIN) in the Bohai Sea in winter (6.529 ?mol L-1) is significantly higher than that in summer (3.717 ?mol L-1). The phosphorus concentration in winter (0.660 ?mol L-1) is also significantly higher than that in summer (0.329 ?mol L-1). Mean silicate concentration in winter (7.858 ?mol L-1) is, however, not significantly different from that in summer (7.200 ?mol L-1). Nutrients also vary considerably in different areas in Bohai Sea. DIN concentration in the Laizhou Bay (4.444 ?mol L-1), for example, is significantly higher than those in the Bohai Bay (2.270 ?mol L-1) and Bohai Strait (2.431 ?mol L-1), which is caused by the discharge of large amounts of nitrogen into Laizhou Bay via Yellow River. The nutrients show different vertical distribution patterns. In summer, nutrients in bottom layer are generally richer than those in surface and middle layers. In winter, however, nutrients are not significantly different in different layers. Compared with historic data, DIN contents have increased continually since the early 1980 s. Based on atomic ratios of different nutrients, nitrogen is still the limiting factor for algal growth in the Bohai Sea.

  19. Applications of nutrient profiling: potential role in diet-related chronic disease prevention and the feasibility of a core nutrient-profiling system

    Microsoft Academic Search

    G Sacks; M Rayner; L Stockley; P Scarborough; W Snowdon; B Swinburn

    2011-01-01

    Background\\/objectives:A number of different nutrient-profiling models have been proposed and several applications of nutrient profiling have been identified. This paper outlines the potential role of nutrient-profiling applications in the prevention of diet-related chronic disease (DRCD), and considers the feasibility of a core nutrient-profiling system, which could be modified for purpose, to underpin the multiple potential applications in a particular country.Methods:The

  20. Quantifying the nutrient flux within a lowland karstic catchment

    NASA Astrophysics Data System (ADS)

    McCormack, T.; Naughton, O.; Johnston, P. M.; Gill, L. W.

    2015-01-01

    Nutrient contamination of surface and groundwaters is an issue of growing importance as the risks associated with agricultural runoff escalate due to increasing demands on global food production. In this study, the nutrient flux occurring within the surface and groundwaters of a lowland karst catchment in western Ireland was investigated with the aid of alkalinity sampling and a hydrological model. Water samples were collected and tested from a variety of rivers, lakes (or turloughs), boreholes and springs at monthly intervals over a three year period. Alkalinity sampling was used to elucidate the contrasting hydrological functioning between different turloughs. Such disparate hydrological functioning was further investigated with the aid of a hydrological model which allowed for an estimate of allogenic and autogenic derived nutrient loading into the karst system. The model also allowed for an investigation of mixing within the turloughs, comparing observed behaviours with the hypothetical conservative behaviour allowed for by the model. Results indicated that at the system outlet to the sea, autogenic recharge had added approximately 35% to the total flow and approximately 85% to the total N-load. Within some turloughs, nutrient loads were found to reduce over the flooded period, even though the turloughs hydrological functioning (and the hydrological model) suggested this should not occur. As such, it was determined that nutrient loss processes were occurring within the system. Denitrification was deemed to be the main process reducing nitrogen concentrations within the turloughs whereas phosphorus loss is thought to occur mostly within the diffuse/epikarst zone.

  1. Insect herbivory accelerates nutrient cycling and increases plant production

    PubMed Central

    Belovsky, G. E.; Slade, J. B.

    2000-01-01

    Ecologists hold two views about the role of herbivory in ecosystem dynamics. First, from a food web perspective in population/community ecology, consumption by herbivores reduces plant abundance. Second, from a nutrient cycling perspective in ecosystem ecology, herbivory sometimes slows down cycling, which decreases plant abundance, but at other times speeds up cycling, which possibly increases plant abundance. The nutrient cycling perspective on herbivory has been experimentally addressed more thoroughly in aquatic systems than in terrestrial systems. We experimentally examined how grasshoppers influence nutrient cycling and, thereby, plant abundance and plant species composition over a period of 5 years. We examined how grasshoppers influence nutrient (nitrogen) cycling (i) by their excrement, (ii) by changing the abundance of and the decomposition rate of plant litter, and (iii) by both. Grasshoppers may speed up nitrogen cycling by changing the abundance and decomposition rate of plant litter, which increases total plant abundance (up to 32.9 g/m2 or 18%), especially, the abundance of plants that are better competitors when nitrogen is more available. However, whether grasshoppers enhance plant abundance depends on how much they consume. Consequently, ecosystems and food web perspectives are not mutually exclusive. Finally, under some conditions, grasshoppers may decrease nutrient cycling and plant abundance. PMID:11106378

  2. Kinetic exploration of nitrate-accumulating microalgae for nutrient recovery.

    PubMed

    Coppens, Joeri; Decostere, Bjorge; Van Hulle, Stijn; Nopens, Ingmar; Vlaeminck, Siegfried E; De Gelder, Leen; Boon, Nico

    2014-10-01

    Within sustainable resource management, the recovery of nitrogen and phosphorus nutrients from waste streams is becoming increasingly important. Although the use of microalgae has been described extensively in environmental biotechnology, the potential of nitrate-accumulating microalgae for nutrient recovery has not been investigated yet. The ability of these marine microorganisms to concentrate environmental nitrate within their biomass is remarkable. The aim of this study was to investigate the application potential of nitrate-accumulating diatoms for nutrient recovery from marine wastewaters. The intracellular nitrate storage capacity was quantified for six marine diatom strains in synthetic wastewater. Amphora coffeaeformis and Phaeodactylum tricornutum stored the highest amount of nitrate with respectively 3.15 and 2.10 g N L(-1) of cell volume, which accounted for 17.3 and 4.6 %, respectively, of the total nitrogen content. The growth and nitrate and phosphate uptake of both diatoms were further analyzed and based on these features P. tricornutum showed the highest potential for nutrient recovery. A mathematical model was developed which included intracellular nitrate storage and the kinetic parameters were derived for P. tricornutum. Furthermore, a simulation study was performed to compare the performance of a proposed microalgal nutrient recovery unit with a conventional denitrification system for marine wastewater treatment. Overall, this study demonstrates the potential application of P. tricornutum for saline wastewater treatment with concurrent nitrogen and phosphorus recycling. PMID:25001595

  3. Sedimentary nutrient dynamics in a tropical estuarine mangrove ecosystem

    NASA Astrophysics Data System (ADS)

    Krishna Prasad, M. Bala; Ramanathan, A. L.

    2008-10-01

    Mangrove sediments play a pivotal role in the nutrient biogeochemical processes by behaving as both source and sink for nutrients and other materials. Surface and core sediments were collected from various locations of the Pichavaram mangrove (India) and analyzed for grain size distribution, nutrients and stable N isotope (? 15N) signatures in order to understand the spatial and vertical distribution of nutrients and biogeochemical processes of the C, N, P and S in this ecosystem. Sand is the dominant fraction followed by silt and clay. Spatial distribution of nutrients is controlled by the external and internal loadings, whereas vertical distribution is largely driven by the in situ microbial activities. Interior mangrove sediments contain higher concentrations of organic carbon (OC) than the estuarine sediments reflecting high rates of organic matter retention. Finer fractions of sediment hold ˜60% OC due to high surface area. At some sampling points, moderately high ? 15N signatures were observed and this may be because of agricultural runoff and aquaculture effluents.

  4. Nutrient fluxes from coastal California catchments with suburban development

    NASA Astrophysics Data System (ADS)

    Melack, J. M.; Leydecker, A.; Beighley, E.; Robinson, T.; Coombs, S.

    2005-12-01

    Numerous streams originate in the mountains fringing California's coast and transport nutrients into coastal waters. In central California, these streams traverse catchments with land covers including chaparral, grazed grasslands, orchards, industrial agriculture and suburban and urban development. Fluvial nutrient concentrations and fluxes vary as a function of these land covers and as a function of considerable fluctuations in rainfall. As part of a long-term investigation of mobilization and fluvial transport of nutrients in catchments bordering the Santa Barbara Channel we have intensively sampled nutrient concentrations and measured discharge during storm and base flows in multiple catchments and subcatchments. Volume-weighted mean concentrations of nitrate generally ranged from 5 to 25 micromolar in undeveloped areas, increased to about 100 micromolar for suburban and most agricultural catchments, and were in excess of 1000 micromolar in catchments with greenhouse-based agriculture. Phosphate concentrations ranged from 2 to 20 micromolar among the catchments. These data are used to examine the premise that the suburbanized portion of the catchments is the primary source of nutrients to the streams.

  5. Future productivity and carbon storage limited by terrestrial nutrient availability

    NASA Astrophysics Data System (ADS)

    Wieder, William R.; Cleveland, Cory C.; Smith, W. Kolby; Todd-Brown, Katherine

    2015-06-01

    The size of the terrestrial sink remains uncertain. This uncertainty presents a challenge for projecting future climate-carbon cycle feedbacks. Terrestrial carbon storage is dependent on the availability of nitrogen for plant growth, and nitrogen limitation is increasingly included in global models. Widespread phosphorus limitation in terrestrial ecosystems may also strongly regulate the global carbon cycle, but explicit considerations of phosphorus limitation in global models are uncommon. Here we use global state-of-the-art coupled carbon-climate model projections of terrestrial net primary productivity and carbon storage from 1860-2100 estimates of annual new nutrient inputs from deposition, nitrogen fixation, and weathering; and estimates of carbon allocation and stoichiometry to evaluate how simulated CO2 fertilization effects could be constrained by nutrient availability. We find that the nutrients required for the projected increases in net primary productivity greatly exceed estimated nutrient supply rates, suggesting that projected productivity increases may be unrealistically high. Accounting for nitrogen and nitrogen-phosphorus limitation lowers projected end-of-century estimates of net primary productivity by 19% and 25%, respectively, and turns the land surface into a net source of CO2 by 2100. We conclude that potential effects of nutrient limitation must be considered in estimates of the terrestrial carbon sink strength through the twenty-first century.

  6. Parallel Exploitation of Diverse Host Nutrients Enhances Salmonella Virulence

    PubMed Central

    Steeb, Benjamin; Claudi, Beatrice; Burton, Neil A.; Tienz, Petra; Schmidt, Alexander; Farhan, Hesso; Mazé, Alain; Bumann, Dirk

    2013-01-01

    Pathogen access to host nutrients in infected tissues is fundamental for pathogen growth and virulence, disease progression, and infection control. However, our understanding of this crucial process is still rather limited because of experimental and conceptual challenges. Here, we used proteomics, microbial genetics, competitive infections, and computational approaches to obtain a comprehensive overview of Salmonella nutrition and growth in a mouse typhoid fever model. The data revealed that Salmonella accessed an unexpectedly diverse set of at least 31 different host nutrients in infected tissues but the individual nutrients were available in only scarce amounts. Salmonella adapted to this situation by expressing versatile catabolic pathways to simultaneously exploit multiple host nutrients. A genome-scale computational model of Salmonella in vivo metabolism based on these data was fully consistent with independent large-scale experimental data on Salmonella enzyme quantities, and correctly predicted 92% of 738 reported experimental mutant virulence phenotypes, suggesting that our analysis provided a comprehensive overview of host nutrient supply, Salmonella metabolism, and Salmonella growth during infection. Comparison of metabolic networks of other pathogens suggested that complex host/pathogen nutritional interfaces are a common feature underlying many infectious diseases. PMID:23633950

  7. [Nutrients in atmospheric wet deposition in the East China Sea].

    PubMed

    Zhu, Yu-Mei; Liu, Su-Mei

    2011-09-01

    92 rainwater samples were collected at Shengsi Archipelago from January 2008 to December 2009. The pH and the concentrations of nutrients (NH4(+), NO3(-) + NO2(-), PO4(3-), SiO3(2-)) were analyzed using spectrophotometry to understand the impacts of the atmospheric wet deposition on the ecosystem of the East China Sea. The results showed that the pH of 85% samples were less than 5.0, and had significant effect on the environment. There were significant differences among monthly average concentrations of nutrients and rainfall and seasonal average wet deposition of nutrients in investigation periods. The annual average wet deposition flux was 52.05 mmol x (m2 x a) (-1) for DIN, 0.08 mmol x (m2 x a) (-1) for PO4(3-), 2.05 mmol x (m2 x a) (-1) for SiO3(2-). The average molar ratios of NO3(-)/NH4(+) is 0.73, N: P ratio is 684: 1, indicating that nutrients composition in rainwater was different from seawater of the East China Sea Shelf (10-150). The wet deposition may change the nutrients structure, pH and lead to change the phytoplankton production in the surface seawater of the East China Sea, even lead to the red tide. PMID:22165245

  8. The imprint of crop choice on global nutrient needs

    NASA Astrophysics Data System (ADS)

    Jobbágy, Esteban G.; Sala, Osvaldo E.

    2014-08-01

    Solutions to meet growing food requirements in a world of limited suitable land and degrading environment focus mainly on increasing crop yields, particularly in poorly performing regions, and reducing animal product consumption. Increasing yields could alleviate land requirements, but imposing higher soil nutrient withdrawals and in most cases larger fertilizer inputs. Lowering animal product consumption favors a more efficient use of land as well as soil and fertilizer nutrients; yet actual saving may largely depend on which crops and how much fertilizer are used to feed livestock versus people. We show, with a global analysis, how the choice of cultivated plant species used to feed people and livestock influences global food production as well as soil nutrient withdrawals and fertilizer additions. The 3 to 15-fold differences in soil nutrient withdrawals per unit of energy or protein produced that we report across major crops explain how composition shifts over the last 20 years have reduced N, maintained P and increased K harvest withdrawals from soils while contributing to increasing dietary energy, protein and, particularly, vegetable fat outputs. Being highly variable across crops, global fertilization rates do not relate to actual soil nutrient withdrawals, but to monetary values of harvested products. Future changes in crop composition could contribute to achieve more sustainable food systems, optimizing land and fertilizer use.

  9. Nutrient enrichment enhances black band disease progression in corals

    NASA Astrophysics Data System (ADS)

    Voss, Joshua D.; Richardson, Laurie L.

    2006-11-01

    Infectious diseases are recognized as significant contributors to the dramatic loss of corals observed worldwide. However, the causes of increased coral disease prevalence and severity are not well understood. One potential factor is elevated nutrient concentration related to localized anthropogenic activities such as inadequate waste water treatment or terrestrial runoff. In this study the effect of nutrient enrichment on the progression of black band disease (BBD) was investigated using both in situ and laboratory experiments. Experimental increases in localized nutrient availability using commercial time release fertilizer in situ resulted in doubling of BBD progression and coral tissue loss in the common reef framework coral Siderastrea siderea. Laboratory experiments in which artificially infected S. siderea colonies were exposed to increased nitrate concentrations (up to 3 ?M) demonstrated similar increases in BBD progression. These findings provide evidence that the impacts of this disease on coral populations are exacerbated by nutrient enrichment and that management to curtail excess nutrient loading may be important for reducing coral cover loss due to BBD.

  10. Effects of cerium oxide nanoparticles on soil enzymatic activities and wheat grass nutrients uptake

    NASA Astrophysics Data System (ADS)

    Li, Biting; Chen, Yirui; Bai, Lingyun; Jacobson, Astrid; Darnault, Christophe

    2015-04-01

    The US National Science Foundation estimated that the use of nanomaterials and nanotechnology would reach a global market value of 1 million this year. Concomitant with the wide applications of nanoparticles is an increasing risk of adverse effects to the environment and human health. As a common nanomaterial used as a fuel catalyst and polish material, cerium (IV) oxide nanoparticles (CeO2 NP) were tested for their potential impact on soil health and plant growth. Through exposure by air, water, and solid deposition, nanoparticles may accumulate in soils and impact agricultural systems. The objectives of this research were to determine whether CeO2 NPs affect the growth of wheat grass and selected soil enzyme activities chose as indicators of soil health. Wheat grass was grown in plant boxes containing CeO2 NPs mixed with agricultural soil at different concentrations. Two control groups were included: one consisting of soil with plants but no CeO2 NPs, and one containing only soil, i.e., no NP or wheat plants added. The plants were grown for 10 weeks and harvested every two weeks in a laboratory under sodium growth lights. At the end of the each growing period, two weeks, soils were assayed for phosphatase, ?-glucosidase, and urease activities, and NPK values. Spectrophotometer analyses were used to assess enzyme activities, and NPK values were tested by Clemson Agricultural Center. Wheat yields were estimated by shoot and root lengths and weights.

  11. Role of nutrient cycling and herbivory in regulating periphyton communities in laboratory streams

    SciTech Connect

    Mulholland, P.J.; Steinman, A.D.; Palumbo, A.V.; Elwood, J.W. (Oak Ridge National Laboratory, TN (United States)); Kirschtel, D.B. ( University of Louisville, KY (United States))

    1992-01-01

    In this study the authors examined the role of nutrient cycling and herbivory in regulating stream periphyton communities. Population, community, and ecosystem-level properties were studied in laboratory stream channels that had nutrient inputs reduced compared to channels where ambient nutrient levels were maintained. They reduced nutrient inputs in four of eight channels by recirculating 90% of the flow, whereas the other four channels received once-through flow of spring water. They examined the interaction between herbivory and nutrients by varying the number of snails (Elimia clavaeformis) among streams with different nutrient input regimes. Reduction in nutrient input via recirculation resulted in lower concentrations of nutrients in the water but did not result in significant differences in biomass, carbon fixation, or algal taxonomic composition. However, herbivory had large effects on these characteristics by reducing biomass and areal rates of carbon fixation and simplifying periphyton taxonomy and physiognomy. Lower rates of nutrient input significantly affected characteristics associated with nutrient cycling. Streams with reduced nutrient inputs had lower periphyton nutrient contents, higher ratios of total:net uptake of P from water, and higher rates of phosphatase activity than streams with ambient nutrient inputs. However, the effects of reduced nutrient input on cycling characteristics were reduced or eliminated by intense herbivory.

  12. Microbial community composition in sediments resists perturbation by nutrient enrichment

    PubMed Central

    Bowen, Jennifer L; Ward, Bess B; Morrison, Hilary G; Hobbie, John E; Valiela, Ivan; Deegan, Linda A; Sogin, Mitchell L

    2011-01-01

    Functional redundancy in bacterial communities is expected to allow microbial assemblages to survive perturbation by allowing continuity in function despite compositional changes in communities. Recent evidence suggests, however, that microbial communities change both composition and function as a result of disturbance. We present evidence for a third response: resistance. We examined microbial community response to perturbation caused by nutrient enrichment in salt marsh sediments using deep pyrosequencing of 16S rRNA and functional gene microarrays targeting the nirS gene. Composition of the microbial community, as demonstrated by both genes, was unaffected by significant variations in external nutrient supply in our sampling locations, despite demonstrable and diverse nutrient-induced changes in many aspects of marsh ecology. The lack of response to external forcing demonstrates a remarkable uncoupling between microbial composition and ecosystem-level biogeochemical processes and suggests that sediment microbial communities are able to resist some forms of perturbation. PMID:21412346

  13. Method and apparatus for determining nutrient stimulation of biological processes

    DOEpatents

    Colwell, Frederick S. (Idaho Falls, ID); Geesey, Gill G. (Bozeman, MT); Gillis, Richard J. (Bozeman, MT); Lehman, R. Michael (Idaho Falls, ID)

    1997-01-01

    A method and apparatus for determining the nutrients to stimulate microorganisms in a particular environment. A representative sample of microorganisms from a particular environment are contacted with multiple support means wherein each support means has intimately associated with the surface of the support means a different nutrient composition for said microorganisms in said sample. The multiple support means is allowed to remain in contact with the microorganisms in the sample for a time period sufficient to measure differences in microorganism effects for the multiple support means. Microorganism effects for the multiple support means are then measured and compared. The invention is particularly adaptable to being conducted in situ. The additional steps of regulating nutrients added to the particular environment of microorganisms can enhance the desired results. Biological systems particularly suitable for this invention are bioremediation, biologically enhanced oil recovery, biological leaching of metals, and agricultural bioprocesses.

  14. Method and apparatus for determining nutrient stimulation of biological processes

    DOEpatents

    Colwell, Frederick S. (Idaho Falls, ID); Geesey, Gill G. (Bozeman, MT); Gillis, Richard J. (Bozeman, MT); Lehman, R. Michael (Idaho Falls, ID)

    1999-01-01

    A method and apparatus for determining the nutrients to stimulate microorganisms in a particular environment. A representative sample of microorganisms from a particular environment are contacted with multiple support means wherein each support means has intimately associated with the surface of the support means a different nutrient composition for said microorganisms in said sample. The multiple support means is allowed to remain in contact with the microorganisms in the sample for a time period sufficient to measure difference in microorganism effects for the multiple support means. Microorganism effects for the multiple support means are then measured and compared. The invention is particularly adaptable to being conducted in situ. The additional steps of regulating nutrients added to the particular environment of microorganisms can enhance the desired results. Biological systems particularly suitable for this invention are bioremediation, biologically enhanced oil recovery, biological leaching of metals, and agricultural bioprocesses.

  15. Method and apparatus for determining nutrient stimulation of biological processes

    DOEpatents

    Colwell, F.S.; Geesey, G.G.; Gillis, R.J.; Lehman, R.M.

    1999-07-13

    A method and apparatus are disclosed for determining the nutrients to stimulate microorganisms in a particular environment. A representative sample of microorganisms from a particular environment are contacted with multiple support means wherein each support means has intimately associated with the surface of the support means a different nutrient composition for microorganisms in the sample. The multiple support means is allowed to remain in contact with the microorganisms in the sample for a time period sufficient to measure difference in microorganism effects for the multiple support means. Microorganism effects for the multiple support means are then measured and compared. The invention is particularly adaptable to being conducted in situ. The additional steps of regulating nutrients added to the particular environment of microorganisms can enhance the desired results. Biological systems particularly suitable for this invention are bioremediation, biologically enhanced oil recovery, biological leaching of metals, and agricultural bioprocesses. 5 figs.

  16. The Quality of Our Nation's Waters: Nutrients and Pesticides

    NSDL National Science Digital Library

    The Quality of Our Nation's Waters: Nutrients and Pesticides is the first report in a series of non-technical publications from the US Geological Survey. Based on findings of the NAWQA (National Water Quality Assessment Program), this first report "presents insights on nutrients and pesticides in water and on pesticides in bed sediment and fish tissue." Subsequent reports will cover other water-quality topics including arsenic, radon, other trace elements, and industrial chemicals, as well as chemical and physical effects on aquatic communities. Targeting resource managers, regulators, and policy makers, the report (.pdf format) provides a general overview of findings on nutrients and pesticides, in addition to technical discussions of "the sources, distributions, and potential effects of these chemicals."

  17. Recycling of food waste as nutrients in Chlorella vulgaris cultivation.

    PubMed

    Lau, Kin Yan; Pleissner, Daniel; Lin, Carol Sze Ki

    2014-10-01

    Heterotrophic cultivation of Chlorella vulgaris was investigated in food waste hydrolysate. The highest exponential growth rate in terms of biomass of 0.8day(-1) was obtained in a hydrolysate consisting of 17.9gL(-1) glucose, 0.1gL(-1) free amino nitrogen, 0.3gL(-1) phosphate and 4.8mgL(-1) nitrate, while the growth rate was reduced in higher concentrated hydrolysates. C. vulgaris utilized the nutrients recovered from food waste for the formation of biomass and 0.9g biomass was produced per gram glucose consumed. The microalgal biomass produced in nutrient sufficient batch cultures consisted of around 400mgg(-1) carbohydrates, 200mgg(-1) proteins and 200mgg(-1) lipids. The conversion of nutrients derived from food waste and the balanced biomass composition make C. vulgaris a promising strain for the recycling of food waste in food, feed and fuel productions. PMID:25128844

  18. Method and apparatus for determining nutrient stimulation of biological processes

    DOEpatents

    Colwell, F.S.; Geesey, G.G.; Gillis, R.J.; Lehman, R.M.

    1997-11-11

    A method and apparatus is described for determining the nutrients to stimulate microorganisms in a particular environment. A representative sample of microorganisms from a particular environment are contacted with multiple support means wherein each support means has intimately associated with the surface of the support means a different nutrient composition for said microorganisms in said sample. The multiple support means is allowed to remain in contact with the microorganisms in the sample for a time period sufficient to measure differences in microorganism effects for the multiple support means. Microorganism effects for the multiple support means are then measured and compared. The invention is particularly adaptable to being conducted in situ. The additional steps of regulating nutrients added to the particular environment of microorganisms can enhance the desired results. Biological systems particularly suitable for this invention are bioremediation, biologically enhanced oil recovery, biological leaching of metals, and agricultural bioprocesses. 5 figs.

  19. Nutrient concentrations and fluxes in the upper catchment of the Miyun Reservoir, China, and potential nutrient reduction strategies.

    PubMed

    Jiao, Jian; Du, Pengfei; Lang, Cong

    2015-03-01

    The Miyun Reservoir is Beijing's main drinking water source. Increased nutrient levels in the reservoir have resulted in an increased risk of harmful algal blooms. One hundred ten water samples were collected at a range of spatial scales in the upper catchment of the Miyun Reservoir and were analyzed for total nitrogen (TN), nitrate (NO3 (-)-N), ammonium (NH4 (+)-N), total phosphorus (TP), and the potassium permanganate index (CODMn). Empirical equations were developed from relationships between nutrient concentrations and the main controls on nutrient, and were used to identify parts of the catchment that should be targeted with nutrient load reduction measures. Cropland was the main source of sediment for the streams, and much of the phosphorus was associated with sediment. The annual mean TP concentrations were closely correlated with both the annual mean suspended sediment concentrations and the ratio of the cropland area to the total basin area. There was a linear relationship between the annual mean TN concentration and the population density in the basins. Soil conservation may play an important role in reducing TP concentrations in the upper reaches of the Chao and Bai Rivers. It may be useful to (1) construct natural riparian buffers and vegetated buffers along croplands close to the watercourses, (2) implement management strategies to reduce nitrogen (N) fertilizer applications, and (3) construct additional wetlands to reduce nutrient loads in the study area. PMID:25673273

  20. Internal nutrient sources and nutrient distributions in Alviso Pond A3W, California

    USGS Publications Warehouse

    Topping, Brent R.; Kuwabara, James S.; Garrett, Krista K.; Takekawa, John Y.; Parchaso, Francis; Piotter, Sara; Clearwater, Iris; Shellenbarger, Gregory G.

    2013-01-01

    Within the Alviso Salt Pond complex, California, currently undergoing avian-habitat restoration, pore-water profilers (U.S. Patent 8,051,727 B1) were deployed in triplicate at two contrasting sites in Pond A3W (“Inlet”, near the inflow, and “Deep”, near the middle of the pond; figs. 1 and 2; table 1, note that tables in this report are provided online only as a .xlsx workbook at http://pubs.usgs.gov/of/2013/1128/). Deployments were conducted in 2010 and 2012 during the summer algal-growth season. Specifically, three deployments, each about 7 weeks apart, were undertaken each summer. This study provides the first measurements of the diffusive flux of nutrients across the interface between the pond bed and water column (that is, benthic nutrient flux). These nutrient fluxes are crucial to pond restoration efforts because they typically represent a major (if not the greatest) source of nutrients to the water column in both ponds and other lentic systems. For soluble reactive phosphorus (SRP, the most biologically available form in solution), benthic flux was positive both years (that is, out of the sediment into the water column; table 2), with the exception of the August 2010 deployment, which exhibited nearly negligible but negative flux. Overall, the average SRP flux was significantly greater at Deep (23.9 ± 8.6 micromoles per square meter per hour (µmol-m-2-h-1); all errors shown reflect the 95-percent confidence interval) than Inlet (12.6 ± 4.9 µmol-m-2-h-1). There was much greater temporal variability in SRP flux in the pond than reported for the lower estuary (Topping and others, 2001). For dissolved ammonia, benthic flux was consistently positive on all six sampling trips, and similar to SRP, the fluxes at Deep (258 ± 49 µmol-m-2-h-1) were consistently greater than those at Inlet (28 ± 11 µmol-m-2-h-1). Dissolved ammonia fluxes reported for South San Francisco Bay by Topping and others (2001) fall in between these values. Once again, greater variability for benthic fluxes determined in the pond was observed relative to adjacent South San Francisco Bay. With the near absence of any measurable concentration gradient, dissolved-nitrate fluxes were consistently negligible in the pond. Silica fluxes are often used to represent sediment diagenetic processes that biogeochemically cycle silica (an important algal macronutrient) between biogenic and inorganic phases (Fanning and Pilson, 1974; Emerson and others, 1984). For South San Francisco Bay, those values are consistently positive from core-incubation experiments. In Pond A3W, dissolved-silica fluxes averaged 49 ± 25 µmol-m-2-h-1 at Inlet and were much higher at Deep (482 ± 370 µmol-m-2-h-1), similar to the spatially variability observed for SRP and dissolved ammonia. An elevated silica flux can stimulate diatom production and subsequent eutrophication effects. Variability in these silica fluxes is consistent with season patterns in pond primary productivity. On the basis of comparisons of dissolved-oxygen flux measurements by profilers and core incubations, it appears that diffusive flux estimates for the sediment in this pond, as one might expected in such benthically productive environments, result in a significant underestimation of true sediment oxygen demand. Therefore, a core incubation experiment was conducted to better quantify the demand. To complement these benthic-flux studies, a diurnal study of nutrient advective flux into and out of the pond was measured during neap and spring tides to provide comparative estimates for allochthonous solute transport (Garret, 2012). Using the two different tides as the probable upper and lower boundaries, we can estimate a range of probable values throughout the year. After converting this advective flux into kg/yr, we can compare it directly to benthic flux estimates for the pond extrapolated over the 2.27 square kilometer (km2) pond surface. Benthic flux of nitrogen species, averaged over all sites and dates, was about 80,000 kilograms per year (kg/yr), well above the adjective flux range of -50 to 1,

  1. Allocation of Nutrients to Somatic Tissues in Young Ovariectomized Grasshoppers

    PubMed Central

    Judd, Evan T.; Hatle, John D.; Drewry, Michelle D.; Wessels, Frank J.; Hahn, Daniel A.

    2010-01-01

    The disposable soma hypothesis predicts that when reproduction is reduced, life span is increased because more nutrients are invested in the soma, increasing somatic repair. Rigorously testing the hypothesis requires tracking nutrients from ingestion to allocation to the soma or to reproduction. Fruit flies on life-extending dietary restriction increase allocation to the soma “relative” to reproduction, suggesting that allocation of nutrients can be associated with extension of life span. Here, we use stable isotopes to track ingested nutrients in ovariectomized grasshoppers during the first oviposition cycle. Previous work has shown that ovariectomy extends life span, but investment of protein in reproduction is not reduced until after the first clutch of eggs is laid. Because ovariectomy does not affect investment in reproduction at this age, the disposable soma hypothesis would predict that ovariectomy should also not affect investment in somatic tissues. We developed grasshopper diets with distinct signatures of 13C and 15N, but that produced equivalent reproductive outputs. These diets are, therefore, appropriate for the reciprocal switches in diet needed for tracking ingested nutrients. Incorporation of stable isotopes into eggs showed that grasshoppers are income breeders, especially for carbon. Allocation to the fat body of nitrogen ingested as adults was slightly increased by ovariectomy; this was our only result that was not consistent with the disposable soma hypothesis. In contrast, ovariectomy did not affect allocation of nitrogen to femoral muscles. Further, allocation of carbon to the fat body or femoral muscles did not appear to be affected by ovariectomy. Total anti-oxidant activities in the hemolymph and femoral muscles were not affected by ovariectomy. These experiments showed that allocation of nutrients was altered little by ovariectomy in young grasshoppers. Additional studies on older individuals are needed to further test the disposable soma hypothesis. PMID:21558244

  2. Global assessment of nutrient loads to the world's largest lakes

    NASA Astrophysics Data System (ADS)

    Fink, Gabriel; Reder, Klara; Malsy, Marcus; Eisner, Stephanie; Flörke, Martina

    2015-04-01

    Lakes are essential resources of drinking water for a large part of mankind. Even so, most of the industrial and domestic waste water is discharged - often untreated - into rivers and streams that are finally the tributaries of these important freshwater bodies. Additionally, diffuse nutrient sources such as fertilizer and atmospheric deposition exacerbate existing algal blooms and low oxygen concentrations in rivers, lakes, and reservoirs. In this tense atmosphere of competing water uses, it is necessary to analyze all sources of pollution as well as their total contributions in order to protect these water bodies against deterioration. Finally, this is a general and urgently needed basis for developing recommendations for involved stakeholders and decision makers. Therefore, the project eartH2Observe, initiated and financed by the European Commission, creates the necessary and underlying quantitative and qualitative hydrological and water use data. In this context, information for global as well as for regional water resource assessments is being prepared based on new earth observations and an ensemble of global hydrological models. As a member of this ensemble, WaterGAP3 provides global estimates of lake water quality relevant parameters on a 5 arc minutes grid, namely total phosphorus and total nitrogen. These nutrient loads to lakes from different sources such as industrial fertilizer, organic fertilizer, domestic loads, atmospheric deposition, and urban surface runoff are estimated for the period 1990 to 2010 in a monthly time step. Whereas nutrient loads and their changes into numerous lakes worldwide are calculated, a special focus is set on nutrient loads into the large and shallow Lake Peipus, which is located between Estonia and Russia and subject to blooms of harmful cyanobacteria. We present estimates, trends, as well as sources of present nutrient loads (TN and TP) to the world's largest lakes with detailed insights to the Lake Peipus situation. Finally global hotspots of nutrient pollution to lakes are identified and discussed.

  3. Nutrient-dependent/pheromone-controlled adaptive evolution: a model

    PubMed Central

    Kohl, James Vaughn

    2013-01-01

    Background The prenatal migration of gonadotropin-releasing hormone (GnRH) neurosecretory neurons allows nutrients and human pheromones to alter GnRH pulsatility, which modulates the concurrent maturation of the neuroendocrine, reproductive, and central nervous systems, thus influencing the development of ingestive behavior, reproductive sexual behavior, and other behaviors. Methods This model details how chemical ecology drives adaptive evolution via: (1) ecological niche construction, (2) social niche construction, (3) neurogenic niche construction, and (4) socio-cognitive niche construction. This model exemplifies the epigenetic effects of olfactory/pheromonal conditioning, which alters genetically predisposed, nutrient-dependent, hormone-driven mammalian behavior and choices for pheromones that control reproduction via their effects on luteinizing hormone (LH) and systems biology. Results Nutrients are metabolized to pheromones that condition behavior in the same way that food odors condition behavior associated with food preferences. The epigenetic effects of olfactory/pheromonal input calibrate and standardize molecular mechanisms for genetically predisposed receptor-mediated changes in intracellular signaling and stochastic gene expression in GnRH neurosecretory neurons of brain tissue. For example, glucose and pheromones alter the hypothalamic secretion of GnRH and LH. A form of GnRH associated with sexual orientation in yeasts links control of the feedback loops and developmental processes required for nutrient acquisition, movement, reproduction, and the diversification of species from microbes to man. Conclusion An environmental drive evolved from that of nutrient ingestion in unicellular organisms to that of pheromone-controlled socialization in insects. In mammals, food odors and pheromones cause changes in hormones such as LH, which has developmental affects on pheromone-controlled sexual behavior in nutrient-dependent reproductively fit individuals across species of vertebrates. PMID:24693353

  4. Efficiency of nutrient acquisition by fine roots and mycorrhizae

    SciTech Connect

    Yanai, R.D.; Fahey, T.J.; Miller, S.L.

    1995-07-01

    It is difficult to assess claims about the adaptive advantages of root foraging strategies without a conceptual model specific enough to allow quantitative prediction and testing. Application of a solute uptake model in combination with a calculation of carbon costs provides a means of assessing the efficiency of carbon expenditures in procuring nutrients from soil. We analyzed the optimal values of root properties, such as longevity, diameter, and mycorrhizal association, that maximized the efficiency of carbon exchange for nutrient uptake in different environments. Optimal longevity was found to decrease with increased soil fertility if the kinetics of nutrient uptake were assumed to decline with increased root longevity. Optimal diameter was found to be smaller than observed in roots, suggesting that other constraints on root structure or function limit their minimum diameter. Mycorrhizal hyphae were found to be more efficient than roots regardless of soil fertility. The steady-state approach to calculating carbon costs and nutrient gain enabled combinations of root and soil properties to be very simply evaluated. However, this approach ignored spatial heterogeneity and temporal variation in root and soil properties, such as aging of roots and patchiness of soil fertility. Furthermore, finding the values of root parameters that maximize root E may not predict the optimal root deployment for the plant, which depends on the relative value of carbon and nutrients in the whole plant. Estimation of the rate of exchange of carbon and nutrients in roots is a necessary step toward an economic analysis of allocation strategies; it also reveals areas of ignorance and helps to identify future research needs.

  5. Effects of nutrient enrichment on mangrove leaf litter decomposition.

    PubMed

    Keuskamp, Joost A; Hefting, Mariet M; Dingemans, Bas J J; Verhoeven, Jos T A; Feller, Ilka C

    2015-03-01

    Nutrient enrichment of mangroves, a common phenomenon along densely populated coastlines, may negatively affect mangrove ecosystems by modifying internal carbon and nutrient cycling. The decomposition of litter exerts a strong influence on these processes and is potentially modified by eutrophication. This study describes effects of N and P enrichment on litter decomposition rate and mineralisation/immobilisation patterns. By making use of reciprocal litter transplantation experiments among fertiliser treatments, it was tested if nutrient addition primarily acts on the primary producers (i.e. changes in litter quantity and quality) or on the microbial decomposers (i.e. changes in nutrient limitation for decomposition). Measurements were done in two mangrove forests where primary production was either limited by N or by P, which had been subject to at least 5 years of experimental N and P fertilisation. Results of this study indicated that decomposers were always N-limited regardless of the limitation of the primary producers. This leads to a differential nutrient limitation between decomposers and primary producers in sites where mangrove production was P-limited. In these sites, fertilisation with P caused litter quality to change, resulting in a higher decomposition rate. This study shows that direct effects of fertilisation on decomposition through an effect on decomposer nutrient availability might be non-significant, while the indirect effects through modifying litter quality might be quite substantial in mangroves. Our results show no indication that eutrophication increases decomposition without stimulating primary production. Therefore we do not expect a decline in carbon sequestration as a result of eutrophication of mangrove ecosystems. PMID:25497680

  6. Nutrient Profiles of Vegetarian and Non Vegetarian Dietary Patterns

    PubMed Central

    Jaceldo-Siegl, Karen; Sabate, Joan; Fraser, Gary E.

    2013-01-01

    Background Differences in nutrient profiles between vegetarian and non vegetarian dietary patterns reflect nutritional differences that may contribute to the development of disease. Objective To compare nutrient intakes between dietary patterns characterized by consumption or exclusion of meat and dairy products. Design Cross-sectional study of 71751 subjects (mean age 59 years) from the Adventist-Health-Study-2. Data was collected between 2002 and 2007. Participants completed a 204-item validated semi-quantitative food frequency questionnaire. Dietary patterns compared were: non vegetarian, semi vegetarian, pesco vegetarian, lacto-ovo vegetarian and strict vegetarian. ANCOVA was used to analyze differences in nutrient intakes by dietary patterns and were adjusted for age, and sex and race. BMI and other relevant demographic data were reported and compared by dietary pattern using chi-square tests and ANOVA. Results Many nutrient intakes varied significantly between dietary patterns. Non vegetarians had the lowest intakes of plant proteins, fiber, ?-Carotene, and Mg than those following vegetarian dietary patterns and the highest intakes of saturated, trans, arachidonic, and docosahexaenoic fatty acids. The lower tails of some nutrient distributions in strict vegetarians suggested inadequate intakes by a portion of the subjects. Energy intake was similar among dietary patterns at close to 2000 kcal/d with the exception of semi vegetarians that had an intake of 1713 kcal/d. Mean BMI was highest in non-vegetarians (mean; standard deviation [SD]) (28.7; [6.4]) and lowest in strict vegetarians (24.0; [4.8]). Conclusions Nutrient profiles varied markedly between dietary patterns that were defined by meat and dairy intakes. These differences can be of interest in the etiology of obesity and chronic diseases. PMID:23988511

  7. Predator-Driven Nutrient Recycling in California Stream Ecosystems

    PubMed Central

    Munshaw, Robin G.; Palen, Wendy J.; Courcelles, Danielle M.; Finlay, Jacques C.

    2013-01-01

    Nutrient recycling by consumers in streams can influence ecosystem nutrient availability and the assemblage and growth of photoautotrophs. Stream fishes can play a large role in nutrient recycling, but contributions by other vertebrates to overall recycling rates remain poorly studied. In tributaries of the Pacific Northwest, coastal giant salamanders (Dicamptodon tenebrosus) occur at high densities alongside steelhead trout (Oncorhynchus mykiss) and are top aquatic predators. We surveyed the density and body size distributions of D. tenebrosus and O. mykiss in a California tributary stream, combined with a field study to determine mass-specific excretion rates of ammonium (N) and total dissolved phosphorus (P) for D. tenebrosus. We estimated O. mykiss excretion rates (N, P) by bioenergetics using field-collected data on the nutrient composition of O. mykiss diets from the same system. Despite lower abundance, D. tenebrosus biomass was 2.5 times higher than O. mykiss. Mass-specific excretion summed over 170 m of stream revealed that O. mykiss recycle 1.7 times more N, and 1.2 times more P than D. tenebrosus, and had a higher N:P ratio (8.7) than that of D. tenebrosus (6.0), or the two species combined (7.5). Through simulated trade-offs in biomass, we estimate that shifts from salamander biomass toward fish biomass have the potential to ease nutrient limitation in forested tributary streams. These results suggest that natural and anthropogenic heterogeneity in the relative abundance of these vertebrates and variation in the uptake rates across river networks can affect broad-scale patterns of nutrient limitation. PMID:23520520

  8. Soil nutrient heterogeneity interacts with elevated CO2 and nutrient availability to determine species and assemblage responses in a model grassland community.

    PubMed

    Maestre, Fernando T; Bradford, Mark A; Reynolds, James F

    2005-12-01

    Interactive effects of atmospheric CO(2) concentration ([CO(2)]), soil nutrient availability and soil nutrient spatial distribution on the structure and function of plant assemblages remain largely unexplored. Here we conducted a microcosm experiment to evaluate these interactions using a grassland assemblage formed by Lolium perenne, Plantago lanceolata, Trifolium repens, Anthoxanthum odoratum and Holcus lanatus. Assemblages exhibited precise root foraging patterns, had higher total and below-ground biomass, and captured more nitrogen when nutrients were supplied heterogeneously. Root foraging responses were modified by nutrient availability, and the patterns of N capture by interactions between nutrient distribution, availability and [CO(2)]. Greater above-ground biomass was observed under elevated CO(2) only under homogeneous conditions of nutrient supply and at the highest availability level. CO(2) interacted with nutrient distribution and availability to determine foliar percentage N and below : above-ground biomass ratios, respectively. Interactions between nutrient distribution and CO(2) determined the relative contribution to above-ground biomass of four of the species. The responses of dominant and subordinate species to [CO(2)] were dependent on the availability and distribution of nutrients. Our results suggest that soil nutrient distribution has the potential to influence the response of plant species and assemblages to changes in [CO(2)] and nutrient availability. PMID:16313646

  9. Phosphorus: A Rate Limiting Nutrient in Surface Waters

    Microsoft Academic Search

    D. L. Correll

    ABSTRACT Phosphorus,is an essential element,for all life forms. It is a mineral,nutrient. Orthophosphate,is the only form,of P that autotrophs,can assimilate. Extracel- lular enzymes,hydrolyze,organic,forms,of P to phos- phate. Eutrophication,is the over-enrichment,of surface waters,with mineral,nutrients. The results are excessive production of autotrophs, especially algae and cyanobacteria.,This high,productivity,leads,to,high bacterial populations and high respiration rates, leading to hypoxia,or anoxia in poorly,mixed,bottom,waters,and at night in

  10. Nutrients transport in catchments of Brazil with different land uses

    NASA Astrophysics Data System (ADS)

    Martinelli, L. A.; Camargo, P. B.; Ometto, J. P. B.; Bernardes, M.

    2003-04-01

    We will present in this study the nutrients transport in catchments of Brazil with different land uses. We will emphasize the transport of dissolved carbon and nitrogen in 7 catchments of the São Paulo State, southeast region of Brazil. These are catchments ranging from 2,000 to 15,000 km2, where much of the main vegetation (Atlantic forest) was already replaced mainly by pasture and sugar cane. Two of these basins are severely affected by domestic and industrial wastewaters. The results from these catchments will be compared with the transport of nutrients in more pristine catchments of the Amazon basin, where most of the original vegetation is still intact.

  11. Defining powerhouse fruits and vegetables: a nutrient density approach.

    PubMed

    Di Noia, Jennifer

    2014-01-01

    National nutrition guidelines emphasize consumption of powerhouse fruits and vegetables (PFV), foods most strongly associated with reduced chronic disease risk; yet efforts to define PFV are lacking. This study developed and validated a classification scheme defining PFV as foods providing, on average, 10% or more daily value per 100 kcal of 17 qualifying nutrients. Of 47 foods studied, 41 satisfied the powerhouse criterion and were more nutrient-dense than were non-PFV, providing preliminary evidence of the validity of the classification scheme. The proposed classification scheme is offered as a tool for nutrition education and dietary guidance. PMID:24901795

  12. Nutrient competition as a determinant for cancer growth

    NASA Astrophysics Data System (ADS)

    Scalerandi, M.; Romano, A.; Pescarmona, G. P.; Delsanto, P. P.; Condat, C. A.

    1999-02-01

    Competition for available nutrients is known to be crucial for cancer development. Based on this fact, a model is proposed that can describe the manifold of morphologies and growth rates characteristic of tumoral growth. The formulation of a consistent set of rules governing the microscopic interactions leads to a system of coupled nonlinear iteration equations. These equations contain both deterministic and stochastic terms and are amenable to direct numerical simulation. They allow us to test the effects of such parameters as the availability, diffusivity, and binding rate of nutrients and the mobility, death, and multiplication rates of cancer cells on tumor morphology and development. Detailed numerical solutions are presented.

  13. Nitrate and nutrient accumulation in two varieties of bermudagrass (Cynodon dactylon (L.) Pers.) as influenced by soil applied fertilizer nutrients 

    E-print Network

    Lovelace, Dale Allen

    1968-01-01

    bermudagrass as influenced by various nutrient treatments and nitrogen levels. . . . 28 16. Zinc ppm in NK-37 bermudagrass as influenced by nutrient treatment, soil texture and nitrogen level. 29 17. Zinc ppm in NK-37 bermudagrass and Coastal bermudagrass.... Iron 6. Manganese 7. Zinc 8. Fe-Mn-Zn-Mo-8-Cu 120 K20 20 8 2 Mo 20 Fe 20 Mn 12 Zn 50 Material KC1 Na2SO4 Na2(Mo04) 2H 0 Che lated Multi Tracin 9. S-Fe-K Combination of individual treatment NX, -37 bermudagrass was grown with all...

  14. Nutrient presses and pulses differentially impact plants, herbivores, detritivores and their natural enemies.

    PubMed

    Murphy, Shannon M; Wimp, Gina M; Lewis, Danny; Denno, Robert F

    2012-01-01

    Anthropogenic nutrient inputs into native ecosystems cause fluctuations in resources that normally limit plant growth, which has important consequences for associated food webs. Such inputs from agricultural and urban habitats into nearby natural systems are increasing globally and can be highly variable, spanning the range from sporadic to continuous. Despite the global increase in anthropogenically-derived nutrient inputs into native ecosystems, the consequences of variation in subsidy duration on native plants and their associated food webs are poorly known. Specifically, while some studies have examined the effects of nutrient subsidies on native ecosystems for a single year (a nutrient pulse), repeated introductions of nutrients across multiple years (a nutrient press) better reflect the persistent nature of anthropogenic nutrient enrichment. We therefore contrasted the effects of a one-year nutrient pulse with a four-year nutrient press on arthropod consumers in two salt marshes. Salt marshes represent an ideal system to address the differential impacts of nutrient pulses and presses on ecosystem and community dynamics because human development and other anthropogenic activities lead to recurrent introductions of nutrients into these natural systems. We found that plant biomass and %N as well as arthropod density fell after the nutrient pulse ended but remained elevated throughout the nutrient press. Notably, higher trophic levels responded more strongly than lower trophic levels to fertilization, and the predator/prey ratio increased each year of the nutrient press, demonstrating that food web responses to anthropogenic nutrient enrichment can take years to fully manifest themselves. Vegetation at the two marshes also exhibited an apparent tradeoff between increasing %N and biomass in response to fertilization. Our research emphasizes the need for long-term, spatially diverse studies of nutrient enrichment in order to understand how variation in the duration of anthropogenic nutrient subsidies affects native ecosystems. PMID:22952814

  15. Nutrient Presses and Pulses Differentially Impact Plants, Herbivores, Detritivores and Their Natural Enemies

    PubMed Central

    Murphy, Shannon M.; Wimp, Gina M.; Lewis, Danny

    2012-01-01

    Anthropogenic nutrient inputs into native ecosystems cause fluctuations in resources that normally limit plant growth, which has important consequences for associated food webs. Such inputs from agricultural and urban habitats into nearby natural systems are increasing globally and can be highly variable, spanning the range from sporadic to continuous. Despite the global increase in anthropogenically-derived nutrient inputs into native ecosystems, the consequences of variation in subsidy duration on native plants and their associated food webs are poorly known. Specifically, while some studies have examined the effects of nutrient subsidies on native ecosystems for a single year (a nutrient pulse), repeated introductions of nutrients across multiple years (a nutrient press) better reflect the persistent nature of anthropogenic nutrient enrichment. We therefore contrasted the effects of a one-year nutrient pulse with a four-year nutrient press on arthropod consumers in two salt marshes. Salt marshes represent an ideal system to address the differential impacts of nutrient pulses and presses on ecosystem and community dynamics because human development and other anthropogenic activities lead to recurrent introductions of nutrients into these natural systems. We found that plant biomass and %N as well as arthropod density fell after the nutrient pulse ended but remained elevated throughout the nutrient press. Notably, higher trophic levels responded more strongly than lower trophic levels to fertilization, and the predator/prey ratio increased each year of the nutrient press, demonstrating that food web responses to anthropogenic nutrient enrichment can take years to fully manifest themselves. Vegetation at the two marshes also exhibited an apparent tradeoff between increasing %N and biomass in response to fertilization. Our research emphasizes the need for long-term, spatially diverse studies of nutrient enrichment in order to understand how variation in the duration of anthropogenic nutrient subsidies affects native ecosystems. PMID:22952814

  16. Absorption of a nutrient solution in chronic alcoholics without nutrient deficiencies and liver cirrhosis.

    PubMed

    Pfeiffer, A; Schmidt, T; Vidon, N; Pehl, C; Kaess, H

    1992-12-01

    Duodenal and jejunal absorption of a nutrient solution at two different caloric loads (1.32 and 3.96 kcal/min = 5.6 and 16.8 kJ/min) was compared in chronic alcoholics without malnutrition, liver cirrhosis, obvious small-bowel dysfunction, and exocrine pancreatic insufficiency and in an age-matched control group, by means of the intestinal perfusion technique. In chronic alcoholics duodenal net absorption of water (p < 0.025), sodium (p < 0.02), potassium (p < 0.005), total nitrogen (p < 0.02), carbohydrates (p < 0.05), and lipids (p < 0.05) was lower than in controls when both caloric loads were administered, but jejunal absorption rates were not decreased. Biliopancreatic secretion did not differ between alcoholics and controls. Higher serum protein leakage in alcoholics was indicated by an increased (p < 0.01) duodenal alpha 1-antitrypsin clearance under low caloric load infusion. It is concluded that the absorptive function of the duodenum is impaired in alcoholics, whereas the upper jejunum is not affected. PMID:1475618

  17. Comparing the nutrient rich foods index with "Go," "Slow," and "Whoa," foods.

    PubMed

    Drewnowski, Adam; Fulgoni, Victor

    2011-02-01

    The US National Heart, Lung, and Blood Institute has grouped foods and beverages into three classes: "Go," "Slow," and "Whoa," as part of a children's guide to eating right. Using nutrient composition data in the 2004 Food and Nutrient Database for Dietary Studies, this descriptive study compared the Go, Slow, and Whoa food classes to tertiles of food rankings generated by the Nutrient Rich Foods Index. A total of 1,045 foods and beverages were first assigned into Go, Slow, and Whoa classes and then ranked by the Nutrient Rich Foods Index nutrient profile model. The Nutrient Rich Foods Index model was based on nine nutrients to encourage: protein, fiber, vitamins A, C, and E, calcium, iron, magnesium, and potassium; and on three nutrients to limit: saturated fat, added sugar, and sodium, all calculated per 100 calories. Both the Go, Slow, and Whoa and the Nutrient Rich Foods Index models readily distinguished between energy-dense and nutrient-rich beverages and foods, and the three Go, Slow, and Whoa classes closely corresponded to tertiles of Nutrient Rich Foods Index scores. There were some disagreements in the class assignment of fortified cereals, some dairy products, and diet beverages. Unlike the Go, Slow, and Whoa model, the Nutrient Rich Foods Index model produced continuous scores that could be used to rank foods within a given class. The study provides an illustration of how diverse nutrient profiling systems can be used to identify healthful foods and beverages. PMID:21272703

  18. Changes in the nutrient content of american diets.

    PubMed

    Huang, Kuo S; Huang, Sophia Wu

    2011-01-01

    As obesity and being overweight continue to increase in the United States, public concern is growing about the quality of American diets. We compare the changes in nutrients contributed by major food groups in the periods 1953-1980 and 1981-2008 and find that there is reduced cholesterol intake and increased calcium intake, but the levels of food energy and total fats increase substantially. To understand how economic factors affect the overall nutritional quality of American diets, we estimate a complete food demand system and conduct a nutrient demand analysis. Among our findings, we conclude that some price manipulations such as subsidizing fruits and vegetables could be effective to increase produce consumption, but the effects of taxing fats to reduce the consumption of fats could be limited. Increasing income would improve intakes of nutrients such as calcium and various vitamins (likely now insufficient), but intakes of nutrients such as energy, saturated fats, and cholesterol (likely now excessive) would also rise with increased income. PMID:22828122

  19. Nutrient disorders of 'Evolution' mealy-cup sage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To produce popular floriculture crops like mealy-cup sage (Salvia farinacea (Benth.)), growers must be equipped with cultural information including the ability to recognize and characterize disorders. Diagnostic criteria of nutrient disorders of mealy-cup sage are absent from the literature. Theref...

  20. Impact of Soil Biochar Applications on Nutrient Leaching

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil applications of biochar, a co-product of lignocellulosic bioenergy production using the pyrolysis platform, has been proposed as a potential means of sequestering carbon, improving soil quality and of returning plant nutrients removed from soils by the harvesting of biomass crops. We used soil ...

  1. Oviposition behavior partitions aquatic landscapes along predation and nutrient gradients

    Microsoft Academic Search

    C. A. Binckley; W. J. Resetarits Jr

    2008-01-01

    That individuals attempt to minimize the ratio of mortality risk\\/growth rate (?\\/g) when foraging within individual habitat patches is well established. Do species partition among spatially discrete communities embedded in complex landscapes in a similar manner? We investigated how 3 ovipositing species (2 Hyla treefrogs and a hydrophilid beetle, Tropisternus lateralis) responded to simultaneous gradients of nutrients and predation risk.

  2. Nutrient budgets in intensive shrimp ponds: implications for sustainability

    Microsoft Academic Search

    Simon J Funge-Smith; Matthew R. P Briggs

    1998-01-01

    Serious production losses have occurred in shrimp producing countries around the world, principally due to poor rearing environments and pathogenic disease. In response to this, shrimp farmers are changing their culture methods. To understand the source and sink of nutrients which affect pondwater quality and effluent impact, the nitrogen, phosphorus and solids budget have been constructed for water exchange systems.

  3. Tillage and nutrient sources impact the productivity of eroded soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil degradation is a consequence of soil organic matter (SOM) losses due to soil disturbance, SOM decomposition, and soil erosion. Manure addition has been shown to enhance SOM, improve soil nutrient status, and increase soil productivity. Manure rates and degree of incorporation may also influenc...

  4. NUTRIENT SYNCHRONY: SOUND IN THEORY, ELUSIVE IN PRACTICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concept of improving animal performance through synchronizing ruminal availability of nutrients has been with us for at least 3 decades. Though theoretically appealing, research and field results have not supported this approach to diet formulation. Why? Essential to successful ruminal synchrony...

  5. Soil nutrient heterogeneity alters competition between two perennial grass species

    Microsoft Academic Search

    Bart Fransen; Hans de Kroon; Frank Berendse

    2001-01-01

    Differences in root foraging behavior between species have been well documented, but the effects of these differences on belowground competitive ability are only beginning to be studied. Here we report the results of a competition experiment in homogeneous and heterogeneous soils between two species that differ in their ability to acquire nutrients from patchy environments. The perennial grasses Festuca rubra

  6. ALGAL RESPONSES TO NUTRIENT LOADING IN GREAT LAKES COASTAL WETLANDS

    EPA Science Inventory

    We are evaluating the influence of nutrient loading on phytoplankton and periphyton in coastal wetlands of the Great Lakes as part of an EPA study associated with the Great Lakes Environmental Indicator (GLEI) project. A primary goal is to assess the role of wetland morphology an...

  7. Nutrient Losses from Row Crop Agriculture in Indiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient losses from agriculture in the Midwestern United States have been identified as contributing to water quality problems such as hypoxia in the Gulf of Mexico, and eutrophication in the great lakes. Fields and catchments in the Cedar Creek sub-watershed of the St. Joseph River basin were mon...

  8. Introduction Wheat development is affected by nutrients, water, light,

    E-print Network

    Liskiewicz, Maciej

    Introduction Wheat development is affected by nutrients, water, light, and other factors/harvest schedule. Wheat moves through a predictable sequence of develop- ment based upon environmental variables in wheat is jointing or when the first node is noticeable. Wheat at jointing could be thriving and have

  9. Herbivores and nutrients control grassland plant diversity via light limitation.

    SciTech Connect

    Borer, Elizabeth T. [Department of Ecology, Evolution, and Behavior, University of Minnesota; et al, et al

    2014-01-01

    Human alterations to nutrient cycles1,2 and herbivore communities3–7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8,9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  10. Nutrient Retention of Vitamins and Minerals in Cooked Whole Grains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recipe calculations are used in many applications, such as food consumption surveys and food service, to estimate the nutrient content of multi-ingredient foods when analytical data are not available. When using uncooked foods as ingredients in recipes, retention factors are needed to account for l...

  11. SEDIMENT AND NUTRIENT ACCUMULATION WITHIN LOWLAND BOTTOMLAND ECOSYSTEMS

    E-print Network

    THE ATCHAFALAYA RIVER BASIN, LOUISIANA C.R. Hupp1 and G.B. Noe1 ABSTRACT Sediment and nutrient deposition, storage, and transformations are important environmental functions of riverine forested wetland ecosystems, yet documentation Basin is the largest contiguously forested riparian wetland in North America and is incurring high

  12. Avoidance of dairy products: Implications for nutrient adequacy and health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy products are an important contributor of many essential nutrients often lacking in the typical North American diet, including calcium, potassium, and vitamin D, and limiting dairy intake may adversely affect health. Dairy exclusion diets may exacerbate the risk of osteoporosis and negatively i...

  13. Nutrient selection in the absence of taste receptor signaling.

    PubMed

    Ren, Xueying; Ferreira, Jozélia G; Zhou, Ligang; Shammah-Lagnado, Sara J; Yeckel, Catherine W; de Araujo, Ivan E

    2010-06-01

    When allowed to choose between different macronutrients, most animals display a strong attraction toward carbohydrates compared with proteins. It remains uncertain, however, whether this food selection pattern depends primarily on the sensory properties intrinsic to each nutrient or, alternatively, metabolic signals can act independently of the hedonic value of sweetness to stimulate elevated sugar intake. Here we show that Trpm5(-/-) mice, which lack the cellular mechanisms required for sweet and several forms of l-amino acid taste transduction, develop a robust preference for d-glucose compared with isocaloric l-serine independently of the perception of sweetness. Moreover, a close relationship was found between glucose oxidation and taste-independent nutrient intake levels, with animals increasing intake as a function of glucose oxidation rates. Furthermore, microdialysis measurements revealed nutrient-specific dopaminergic responses in accumbens and dorsal striatum during intragastric infusions of glucose or serine. Specifically, intragastric infusions of glucose induced significantly higher levels of dopamine release compared with isocaloric serine in both ventral and dorsal striatum. Intragastric stimulation of dopamine release seemed to depend on glucose utilization, because administration of an anti-metabolic glucose analog resulted in lower dopamine levels in striatum, an effect that was reversed by intravenous glucose infusions. Together, our findings suggest that carbohydrate-specific preferences can develop independently of taste quality or caloric load, an effect associated with the ability of a given nutrient to regulate glucose metabolism and stimulate brain dopamine centers. PMID:20534849

  14. Optimizing Nutrient Management for Sustainable Bio-energy Feedstock Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn grain and stover are both being evaluated as feedstock sources for bio-energy production. To meet current and future demands for corn, both short- and long-term effects on nutrient cycling, physical properties, and biological activity in soils must be understood. Our project goal was to increas...

  15. Nutrient status: a missing factor in phenological and pollen research?

    PubMed Central

    Jochner, Susanne

    2013-01-01

    Phenology ranks among the best ecosystem processes for fingerprinting climate change since temperature explains a high percentage of the interannual or spatial variation in phenological onset dates. However, roles of other environmental variables, such as foliar nutrient concentrations, are far from adequately understood. This observational study examined the effects of air temperature and 11 nutrients on spring phenology of Betula pendula Roth (birch) along an urban–rural gradient in Munich, Germany, during the years 2010/2011. Moreover, the influence of temperature, nutrients, and air pollutants (NO2 and O3) on the amounts of pollen and catkin biomass in 2010 was evaluated. In addition to the influence of higher temperatures advancing phenological onset dates, higher foliar concentrations of potassium, boron, zinc, and calcium were statistically significantly linked to earlier onset dates. Since flushing of leaves is a turgor-driven process and all the influential nutrients are involved in cell extension, membrane function, and stability, there might be a reasonable physiological interpretation of the observed association. The amounts of pollen were negatively correlated with temperature, atmospheric NO2, and foliar iron concentration, suggesting that these variables restrict pollen production. The results of this study suggested an influence of nutritional status on both phenology and pollen production. The interaction of urbanization and climate change should be considered in the assessment of the impact of global warming on ecosystems and human health. PMID:23630329

  16. Nutrient Transport in Dredged Reaches of Agricultural Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are a vital component of many of the more productive agricultural landscapes in the United States. These systems often require intensive management to ensure adequate removal of water from the system, but little is known about how ditch management affects nutrient losse...

  17. Original article The effect of feed enzymes on nutrient

    E-print Network

    Paris-Sud XI, Université de

    Original article The effect of feed enzymes on nutrient and energy retention in young racing. No difference in body weight was observed between groups. Despite feed restriction, intake was higher for enzyme-sup- plemented diet. When related to feed intake, excreta were lower by 11% for enzyme-supplemented diet. Enzyme

  18. Effect of nutrient enrichment on seagrass associated meiofauna in Tanzania.

    PubMed

    Daudi, Lillian Nduku; Lugomela, Charles; Uku, Jacqueline Nduku; De Troch, Marleen

    2012-12-01

    Abundance, diversity and community structure of meiofauna, with special emphasis on epiphytic harpacticoid copepods, occurring in Tanzanian seagrass beds under various nutrient inputs was determined. All measured parameters for epiphytic meiofauna and diatoms (fucoxanthin) were negatively affected by nutrient input and this was detected even at the higher taxonomic levels of meiofauna, supporting the validity of higher taxon surrogacy in environmental impact studies. However, benthic meiofauna and other biofilm characteristics (chlorophyll a) did not show any difference between sites suggesting that nutrient enrichment had less impact on these variables. This indicates a differential impact of pollution on epiphytic vs. benthic communities. Consequently, different trophic levels will be impacted in various ways and hence the effects of pollution on the overall ecosystem functioning of seagrass beds are complex and not straightforward. Although the seagrass plants themselves don't show any major changes under different nutrient input, associated organisms that guarantee energy flow at basal levels of the food web in this ecosystem can be largely impacted. PMID:23072915

  19. Nutrient losses from an irrigated watershed in southern Idaho

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water, sediment and nutrients flowing into and out of the 82,000 ha Twin Falls, ID irrigation tract were measured from 2005 to 2008. Approximately 80% of the water flowing into the watershed was irrigation water diverted from the Snake River. About 40% of the watershed inflow returned to the Snake R...

  20. Cadmium: A nutrient for the marine diatom Thalassiosira weissflogii

    Microsoft Academic Search

    JENNIFER G. LEE; SAMANTHA B. ROBERTS; FRANÇOIS M. M. MOREL

    1995-01-01

    Although cadmium is known to be very toxic, it exhibits nutrientlike vertical concentration profiles in the open ocean. Recent work has shown that under conditions of zinc limitation, cadmium enhances the growth of the marine diatom Thalassiosira weissflogii. Here, we conclusively demonstrate that Cd is a nutrient for T. weissjlogii at inorganic Zn and Cd concentrations typical of surface seawater,

  1. Photosynthetic carbon allocation: Effects of planktivorous fish and nutrient enrichment

    Microsoft Academic Search

    Sofia Perin; David R. S. Lean; Frances R. Pick; Asit Mazumder

    2002-01-01

    The proportions of lipid, polysaccharide and protein profoundly influence the nutritional value of food for planktonic organisms. Here, we investigated the ef- fects of nutrients (N and P) and planktivorous fish (Phox- inus sp.) on the partitioning of photosynthetically fixed 14C-labelled bicarbonate into macromolecules (lipids, polysaccharides and proteins) and low molecular weight (LMW) metabolites of epilimnetic phytoplankton living in large

  2. Recent advances in modeling nutrient utilization in ruminants1

    Microsoft Academic Search

    E. Kebreab; J. Dijkstra; A. Bannink

    2009-01-01

    Mathematical modeling techniques have been applied to study various aspects of the ruminant, such as rumen function, post-absorptive metabolism and product composition. This review focuses on advances made in modeling rumen fermentation and its associated rumen disorders, and energy and nutrient utilization and excretion with respect to environmental issues. Accurate prediction of fermentation stoichiometry has impact on estimating the type

  3. Nutrient content of the moist tropical forest of Ghana

    Microsoft Academic Search

    D. J. Greenland; J. M. L. Kowal

    1960-01-01

    Summary The total weight of vegetation on an area of just over 1 acre of old secondary forest in the moist forest zone of Ghana has been determined, and found to be equivalent to roughly 150 tons per acre dry weight. The nutrient content of each component of the vegetation was also determined and showed that the amounts of the

  4. Do nutrients limit algal periphyton in blackwater coastal plain streams?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many streams draining the U.S. Atlantic coastal plain are listed as having impaired water quality because of low levels of dissolved oxygen (DO). Nutrient enrichment from nonpoint source pollution, and associated algal and bacterial growth (which create a biological oxygen demand), may be the cause...

  5. Predators Accelerate Nutrient Cycling in a Bromeliad Ecosystem

    E-print Network

    Srivastava, Diane

    on nutrient cycling by using the detritus-based insect community in bromeliads. We demonstrate that predation containing either no insects, detritivores only, or detritivores and predators. The presence of detritivores is consumed, the insects will pref- erentially retain N in their body tissues and release P. Predation

  6. MODELING SEDIMENT-NUTRIENT FLUX AND SEDIMENT OXYGEN DEMAND

    EPA Science Inventory

    Depositional flux of particulate organic matter in bottom sediments affects nutrients cycling at the sediment-water interface and consumes oxygen from the overlying water in streams, lakes, and estuaries. This project deals with analytical modeling of nitrogen and carbon producti...

  7. Stoichiometric nutrient balance and origin of coastal eutrophication

    Microsoft Academic Search

    Dubravko Justi?; Nancy N. Rabalais; R. Eugene Turner

    1995-01-01

    We present here an analysis of the stoichiometry of dissolved nutrients in 10 large world rivers, Amazon, Changjiang, Huanghe, Mackenzie, Mississippi, Po, Rhine, Seine, Yukon and Zaire, and in two river-dominated coastal ecosystems prone to eutrophication, the northern Adriatic Sea and the northern Gulf of Mexico. Our analysis suggests that proportions of dissolved silica (Si), nitrogen (N) and phosphorous (P)

  8. Variable Responses of Lowland Tropical Forest Nutrient Status

    E-print Network

    Harms, Kyle E.

    Variable Responses of Lowland Tropical Forest Nutrient Status to experimental fertilization and litter manipulation treatments in an old-growth lowland tropical forest,5 Jennifer S. Powers,6 Michael Kaspari,7 Milton N. Garcia,2 and Benjamin L. Turner2 1 Centre for Ecology

  9. FIELD STUDY OF NUTRIENT CONTROL IN A MULTICELL LAGOON

    EPA Science Inventory

    This report covers nutrient control in a serially arranged, multicell aerated lagoon system over a three year period. The objective was to develop reliable technology for reducing phosphorus and for converting ammonia-nitrogen to nitrate-nitrogen. A six-cell lagoon was modified i...

  10. EFFECT OF RAIN INTENSITY ON NUTRIENT LOSS: LABORATORY STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil surface structure has a significant influence on percolation and runoff rate. We hypothesized that seal formation on the soil surface will considerably effect "mixing zone" formation and nutrient loss through runoff. Effect of rain intensity 15-100 mm h-1 and surface structural condition (degra...

  11. Diet, nutrients, phytochemicals, and cancer metastasis suppressor genes

    E-print Network

    Collins, Gary S.

    Abbreviations BRMS Breast cancer metastasis suppressor CTGF Connective tissue growth factor DHA DocosahexaenoicDiet, nutrients, phytochemicals, and cancer metastasis suppressor genes Gary G. Meadows # Springer and mortality of cancer patients is metastasis. There exists a relative lack of specific therapeutic approaches

  12. MINERAL NUTRIENT REQUIREMENTS FOR REGULATING THE GROWTH OF PLANT TISSUE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mineral nutrient requirements of nonembryogenic citrus callus were characterized by breaking the MS salts into the following five factors – NH4NO3, KNO3, Ca-Mg-Cl-Mn-SO4-PO4, metals, and Fe-EDTA. A D-optimal response surface experimental design where each factor was varied over a range of conce...

  13. Assessing Nutrient Transport Following Dredging of Agricultural Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are vital for many agricultural landscapes in the U.S. Previous research has indicated that dredging agricultural drainage ditches may degrade water quality. In this study, we monitored nutrient transport in two drainage ditches for six years (2003-2008), during which t...

  14. NOAA Technical Report NMFS 32 Nutrient Distributions for

    E-print Network

    32 NOAA Technical Report NMFS 32 Nutrient Distributions for Georges Bank and Adjacent Waters National Oceanic and Atmospheric Administration National Marine Fisheries Service #12;NOAA TECHNICAL, and publishes statistics on various phases of the industry. The NOAA Technical Report NMFS series

  15. MACRO NUTRIENT Hans-Rudolf Berthoud, Ph.D.

    E-print Network

    Galef Jr., Bennett G.

    -Feeding Experiments and Protein Intake 22 8 Theoretical Implications of Failures to Self-Select 23 9 Learning, protein, fat, calcium, and oxygen, as well as internal effectors capable of redressing any detectedNEURAL and METABOLIC CONTROL of MACRO NUTRIENT INTAKE Edited by Hans-Rudolf Berthoud, Ph.D. Randy J

  16. Dietary Protein: An Essential Nutrient For Bone Health

    Microsoft Academic Search

    Jean-Philippe Bonjour

    2005-01-01

    Nutrition plays a major role in the development and maintenance of bone structures resistant to usual mechanical loadings. In addition to calcium in the presence of an adequate vitamin D supply, proteins represent a key nutrient for bone health, and thereby in the prevention of osteoporosis. In sharp opposition to experimental and clinical evidence, it has been alleged that proteins,

  17. CONTROLS OF SEAGRASS EPIPHYTE ABUNDANCE: DOES LIGHT TRUMP NUTRIENTS?

    EPA Science Inventory

    Epiphytes on seagrass growing in the lower intertidal were examined along an estuarine gradient within Yaquina Bay, Oregon over a period of 4 years. The Yaquina Estuary receives high levels of nutrients from the watershed during the wet season and from the ocean during the dry s...

  18. Mechanisms of cancer inhibition by anti-oxidant nutrients

    Microsoft Academic Search

    G Shklar

    1998-01-01

    The cancer inhibitory properties of anti-oxidant micronutrients have been well established in experimental animal models and cell culture studies. Human studies have also tended to indicate an inhibition of various forms of cancer and the regression of some precancerous lesions. The biological mechanisms for cancer inhibition and regression are now gradually becoming understood, and the anti-oxidant nutrients appear to act

  19. Empirical approach to predict leached nutrients from landfill site.

    PubMed

    Barman, Pranab Jyoti; Kartha, Suresh A; Pradhan, Bulu

    2015-05-01

    An empirical approach is made in this investigation to predict the leached concentrations of sodium (Na), calcium (Ca), and potassium (K) in the effluents from a landfill site. Water at certain predetermined inflow filling rate is applied to a specific ponding depth, at the top of an experimental column filled with landfill refuse soil at the top (upper layer) and normal local soil at the bottom (base layer). The water infiltrates into the upper layer soil, percolates through the pores in upper and base layers, and in the process leaches the nutrients from the soils that are collected at the bottom of the column. The experimentations were for different combinations of heights of upper and base layer soils, water ponding depth, and inflow filling rates. The nutrient concentrations in the outflow leachates are measured using flame photometer. The observations showed mixed responses of leaching and trapping of nutrients in the soil layers for the various combinations. The experimental observations also inferred that the nutrient leaching is more for cases involving higher ponding depths and higher inflow filling rates. Empirical relationships with respect to the geometrical parameters, to predict the leached concentrations of Na, Ca, and K, are developed from the experimental observations using nonlinear least squares regressive techniques. Exponential equations gave the best empirical fit among various nonlinear relations in the regression technique. The empirical models also predicted well for each subcategory of independent variables that are substantiated by high correlation coefficients. PMID:25410312

  20. Salinity–mineral nutrient relations in horticultural crops

    Microsoft Academic Search

    S. r. Grattan; C. m. Grieve

    1998-01-01

    The relations between salinity and mineral nutrition of horticultural crops are extremely complex and a complete understanding of the intricate interactions involved would require the input from a multidisciplinary team of scientists. This review addresses the nutrient elements individually and we emphasise research directed towards the organ, whole-plant and field level. We have attempted to synthesise the literature and reconcile

  1. Nutrient chemistry of the water column of Lake Tanganyika

    Microsoft Academic Search

    J. M. EDMOND; R. F. STALLARD; H. CRAIG; V. CRAIG; R. F. WEISS; G. W. COULTER

    1993-01-01

    Lake Tanganyika shows pcrmancnt thermal stratification with deep-water temperatures that have been stable over the period of observation (since 1939). The lake is anoxic below - 150-m depth. In general the nutrients show Redficld behavior save in the deep waters of the northern basin where large excesses of phosphate and ammonia are prcscnt. Bacterial disproportionation of organic material probably plays

  2. PHOSPHORUS FEEDING AND MANURE NUTRIENT RECYCLING ON WISCONSIN DAIRY FARMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient management regulations for livestock operations are focused on a farm¿s ability to recycle the phosphorus (P) contained in manure. Most efforts to improve dairy manure management emphasize manure handling, storage, and land application techniques. Little is known about relationships betwee...

  3. Nutrient limitation of phytoplankton in a central Arizona reservoir

    Microsoft Academic Search

    Nancy L. Crane; Milton R. Sommerfeld

    1976-01-01

    The influence of added nutrients nitrogen, phosphorus and carbon on the phytoplankton of a small recreational reservoir in central Arizona was investigated during the summer, 1974. Polyethylene bags were used to isolate lake water and the natural populations for the addition of nitrogen, phosphorus and carbon individually and in combination. A large increase in phytoplankton numbers, extractable chlorophyll, pH and

  4. Techniques to Enhancing Sustainable Nutrient and Irrigation Management for Potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two aspects of nutrient and irrigation best management practices (BMP) in relation to sustainable agricultural production systems described in this paper are: (i) application of crop simulation model for decision support system; and (ii) real-time, automated measurement of soil water content to aid ...

  5. Rhythmic patterns of nutrient acquisition by wheat roots

    Microsoft Academic Search

    Sergey ShabalaB; Andrew KnowlesA

    2002-01-01

    Oscillatory patterns in H+, K+, Ca2+ and Cl- uptake were observed at different regions of the root surface, including root hairs, using a non-invasive ion flux measuring technique (the MIFE™ technique). To our knowledge, this is the first report of ultradian oscillations in nutrient acquisition in the mature root zone. Oscillations of the largest magnitude were usually measured in the

  6. Flow Dynamics and Nutrient Reduction in Rain Gardens

    EPA Science Inventory

    The hydrological dynamics and changes in stormwater nutrient concentrations within rain gardens were studied by introducing captured stormwater runoff to rain gardens at EPA?s Urban Water Research Facility in Edison, New Jersey. The runoff used in these experiments was collected...

  7. Original article Nutrient cycling in deciduous forest ecosystems of

    E-print Network

    Boyer, Edmond

    Original article Nutrient cycling in deciduous forest ecosystems of the Sierra de Gata mountains and compared with the returns found in four deciduous oak (Quercus pyrenaica Wild.) forests (1990-1993) located. This similarity is logical since the plots harbour the same deciduous species which are, however, subjected

  8. Water, weed, and nutrient management practices in organic blackberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of our study is to investigate the effects of organic management on plant and soil water and nutrient relations, plant growth, yield, and fruit quality in an organic trailing blackberry production system. Treatments include: cultivar ('Marion' and 'Black Diamond'); irrigation (post-harve...

  9. Retrofitting SBR systems to nutrient removal in sensitive tourist areas

    Microsoft Academic Search

    R. Tasli; N. Artan; D. Orhon

    2001-01-01

    Retrofitting of existing SBR systems for nutrient removal is evaluated and defined for small communities in sensitive coastal areas, with seasonal fluctuations in wastewater quantity and quality. The proposed approach is developed by means of basic process stoichiometry and verified using ASM2d. The efficiency of retrofitting is found to rely on the delicate balance between the overall sludge age, the

  10. Exploring the Sulfur Nutrient Cycle Using the Winogradsky Column

    ERIC Educational Resources Information Center

    Rogan, Brian; Lemke, Michael; Levandowsky, Michael; Gorrell, Thomas

    2005-01-01

    The Winogradsky column demonstrates how the metabolic diversity of prokaryotes transforms sulfur to different forms with varying redox states and hence, supplies nutrients and/or energy to the organism. The Winogardsky column is an excellent way to show that not all bacteria are pathogens and they have an important role in the geochemical cycling…

  11. Patterns of nutrient loading in forested and urbanized coastal streams

    Microsoft Academic Search

    M. H. Wahl; H. N. McKellar; T. M. Williams

    1997-01-01

    As part of a larger investigation of the effects of coastal urbanization on estuaries, stream nutrient loading was examined over a range of hydrologic and seasonal conditions for an urbanized and a forested watershed (11 ha versus 37 ha). Despite the smaller size, the urbanized stream produced 72% greater annual streamflow volume (162 versus 94 × 103m3 · yr?1), and

  12. NUTRIENT TRANSPORT IN THE LAKE POINSETT SYSTEM JACK M. SKILLE

    E-print Network

    NUTRIENT TRANSPORT IN THE LAKE POINSETT SYSTEM BY JACK M. SKILLE A thesis submitted in partial. An annual 2.07x 10~ m 3 surface discharge into Lake Poinsett transported 3 oc~,; 1.66 x 104 kg (PO4, and 70% of the phosphorus load was retained by the lake or lost by ways other than water discharge

  13. Masting in whitebark pine (Pinus albicaulis) depletes stored nutrients.

    PubMed

    Sala, Anna; Hopping, Kelly; McIntire, Eliot J B; Delzon, Sylvain; Crone, Elizabeth E

    2012-10-01

    • In masting trees, synchronized, heavy reproductive events are thought to deplete stored resources and to impose a replenishment period before subsequent masting. However, direct evidence of resource depletion in wild, masting trees is very rare. Here, we examined the timing and magnitude (local vs individual-level) of stored nutrient depletion after a heavy mast event in Pinus albicaulis. • In 2005, the mast year, we compared seasonal changes in leaf and sapwood nitrogen (N) and phosphorus (P) concentrations and leaf photosynthetic rates in cone-bearing branches, branches that never produced cones, and branches with experimentally removed cones. We also compared nutrient concentrations in cone branches and branches that had never had cones between 2005 and 2006, and measured tree ring width and new shoot growth during 2005. • During the mast year, N or P depletion occurred only in tissue fractions of reproductive branches, where photosynthetic rates were reduced. However, by the end of the following year, nutrients were depleted in all branches, indicating individual-level resource depletion. New shoot and radial growth were not affected by masting. • We provide direct evidence that mast events in wild trees deplete stored nutrients. Our results highlight the importance of evaluating reproductive costs over time and at the individual level. PMID:22889129

  14. Modelling consumer exposures to nutrients and additives in animal products

    Microsoft Academic Search

    D. R. Tennant; P. Bequet; D. Jans

    2009-01-01

    Current guidelines for assessing human exposures to nutrients and other substances used in animal feed are based on methods used for veterinary pharmaceuticals. These methods assume high-level daily consumption of animal products and do not take account of differences between species or between consuming humans. A more detailed dietary modelling approach is described, which takes these factors into account as

  15. Interaction between Plant Nutrients: IV. Interaction between Calcium and Phosphate

    Microsoft Academic Search

    Svend Tage Jakobsen

    1993-01-01

    The interaction between calcium and phosphate is complex because these ions both support and counteract each other. The supporting effect is due to a simultaneous uptake and translocation of calcium and phosphate. The counteracting effect is caused by precipitation of less soluble calcium phosphates at the vicinity of nutrient-absorbing roots.At high activity ratios between potassium and calcium the risk of

  16. Do Megafauna influence spatial patterns of nutrient distribution?

    E-print Network

    Malhi, Yadvinder

    as "nutrient arteries" in the system. Further study of this system is required to fully understand the role for numerous discussions and help with refining methods and sampling design, as well as dissipating statistical doubts. I wish to thank Sam Moore for great deal of advice and help with the planning and the logistics

  17. Functional diversity governs ecosystem response to nutrient enrichment

    Microsoft Academic Search

    Florence D. Hulot; Gérard Lacroix; Françoise Lescher-Moutoué; Michel Loreau

    2000-01-01

    The relationship between species diversity and ecosystem functioning is a central topic in ecology today. Classical approaches to studying ecosystem responses to nutrient enrichment have considered linear food chains. To what extent ecosystem structure, that is, the network of species interactions, affects such responses is currently unknown. This severely limits our ability to predict which species or functional groups will

  18. Fungicide and Nutrient Transport with Runoff from Creeping Bentgrass Turf

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The detection of pesticides and excess nutrients in surface waters of urban watersheds has lead to increased environmental concern and suspect of contaminant contributions from residential, urban, and recreational sources. Highly managed biotic systems such as golf courses and commercial landscapes ...

  19. Nutrient enrichment, biodiversity loss, and consequent declines in ecosystem productivity

    E-print Network

    Minnesota, University of

    Nutrient enrichment, biodiversity loss, and consequent declines in ecosystem productivity Forest in biodiversity, species compo- sition, and ecosystem functioning. It remains unknown whether such shifts in biodiversity and species composition may, them- selves, be major contributors to the total, long-term impacts

  20. CHALLENGES IN INTEGRATING CAFO NUTRIENT MANAGEMENT WITH ENVIRONMENTAL STEWARDSHIP

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In general, 70 to 90% of nutrients fed to livestock subsequently end up in manure and can potentially be lost to the environment. Thus, the effects of livestock operations, especially larger concentrated animal feeding operations (CAFO), on the environment are a growing concern among many groups...

  1. UPSTREAM-TO-DOWNSTREAM CHANGES IN NUTRIENT EXPORT RISK

    EPA Science Inventory

    One of the early operating principles of landscape ecology was the importance of studying the movement of energy, nutrients, and biota in the horizontal or x,y plane (Risser et al. 1984). The new focus on horizontal movement was in part based on the recognition that many ecol...

  2. Measuring Nitrification: A Laboratory Approach to Nutrient Cycling.

    ERIC Educational Resources Information Center

    Hicks, David J.

    1990-01-01

    Presented is an approach to the study of nutrient cycling in the school laboratory. Discussed are obtaining, processing, and incubating samples; extraction of ions from soil; procedures for nitrate and ammonium analysis; data analysis; an example of results; and other aspects of the nitrogen cycle. (CW)

  3. USDA National Nutrient Database for Standard Reference, Release 22

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Nutrient Database for Standard Reference, Release 22 contains data for over 7,500 food items for up to 143 food components when a complete profile is available for a food item. It replaces the previous release, SR21, issued in September 2008. Data in SR22 supersede values in the printed Han...

  4. USDA National Nutrient Database for Standard Reference, Release 21

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Nutrient Database for Standard Reference, Release 21 contains data for 7,414 food items for up to 140 food components when a complete profile is available for a food item. It replaces the previous release, SR20, issued in September 2007. Data in SR21 supersede values in the printed Handbook...

  5. Nutrient removal from eutrophic lake water by wetland filtration

    Microsoft Academic Search

    M. F. Coveney; D. L. Stites; E. F. Lowe; L. E. Battoe; R. Conrow

    2002-01-01

    Lake Apopka is a large (125 km2), shallow (mean depth 1.6 m) lake in Florida, USA. The lake was made hypereutrophic by phosphorus loading from floodplain farms and has high levels of nutrients, phytoplankton (Chl a 80 ?g l?1), and suspended matter. The restoration plan developed by the St. Johns River Water Management District encompasses the biomanipulation concept in which

  6. Modeling of nutrient concentrations in the river Loktinka, Western Siberia

    NASA Astrophysics Data System (ADS)

    Sheludkov, Artyom; Kiesel, Jens; Veshkurtseva, Tatyana

    2014-05-01

    Nutrient pollution is the process where too many nutrients, mainly nitrogen and phosphorus, are added to bodies of water and act as fertilizer, causing excessive growth of algae and threatening the natural species assemblages. The investigated catchment area is the river Loktinka which is located in the southern part of the West Siberian Plain, in the forest-steppe vegetation region. One of the most serious contaminant of the surface waters in the region are nutrients. The main input of nutrients comes from untreated runoff from agricultural fields and pastures. To mitigate agricultural non-point source pollution, simulation tools can aid in the development of temporal and spatial management plans. This study presents a software application of a Geohydrological Analysis Model, developed by Prof. Kalinin, Tyumen State University, Russian Federation (1998) for the region. The model is based on "Runoff Forming Surfaces", which are a distinguished part of the catchment characterized by a set of natural components such as land use, soil and elevation. These areas are relatively homogeneous and lead to the same parameters for representing the hydrological cycle. The model is used to simulate the water quality situation which was sampled during spring runoff in 2013. Results of the Siberian Geohydrological Analysis Model are compared to simulations carried out with the Soil and Water Assessment Tool (SWAT).

  7. Temporal Changes in the Spatial Variability of Soil Nutrients

    SciTech Connect

    R. L. Hoskinson; J. R. Hess; R. S. Alessi

    1999-07-01

    This paper reports the temporal changes in the spatial variability of soil nutrient concentrations across a field during the growing season, over a four-year period. This study is part of the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project at the INEEL. Uniform fertilization did not produce a uniform increase in fertility. During the growing season, several of the nutrients and micronutrients showed increases in concentration although no additional fertilization had occurred. Potato plant uptake did not explain all of these changes. Some soil micronutrient concentrations increased above levels considered detrimental to potatoes, but the plants did not show the effects in reduced yield. All the nutrients measured changed between the last sampling in the fall and the first sampling the next spring prior to fertilization. The soil microbial community may play a major role in the temporal changes in the spatial variability of soil nutrient concentrations. These temporal changes suggest potential impact when determining fertilizer recommendations, and when evaluating the results of spatially varying fertilizer application.

  8. HETEROGENEOUS ORTHOTROPIC ELASTICTY ABOUT A NUTRIENT FORAMEN VIA MICROINDENTATION

    Microsoft Academic Search

    Satchi Venkataraman

    We determined the spatial distribution of orthotropic engineering constants about a nutrient foramen using the combined techniques of microindentation, polarized microscopy, and elasticity transformation. One goal of this estimation was to provide an independent verification of our related work(2) that relied upon more laborious techniques, and we found variations in the constants that were quite similar to our previous findings.(2)

  9. Hydrogen peroxide mediates plant root cell response to nutrient deprivation

    Microsoft Academic Search

    Ryoung Shin; Daniel P. Schachtman

    2004-01-01

    Potassium (K+) is an essential nutrient required by plants in large quantities, but changes in soil concentrations may limit K+ acquisition by roots. It is not known how plant root cells sense or signal the changes that occur after the onset of K+ deficiency. Changes in the kinetics of Rb+ uptake in Arabidopsis roots occur within 6 h after K+

  10. Modelling biological nutrient removal activated sludge systems—a review

    Microsoft Academic Search

    Zhi-rong Hu; M. C Wentzel; G. A Ekama

    2003-01-01

    The external nitrification (EN) biological nutrient removal (BNR) activated sludge (ENBNRAS) system shows considerable promise for full-scale implementation. As an aid for this implementation, a mathematical simulation model would be an invaluable tool. To develop such a model, a study was conducted to select the most suitable simulation model to serve as a starting point for further development. For this,

  11. EXTERNAL NITRIFICATION IN BIOLOGICAL NUTRIENT REMOVAL ACTIVATED SLUDGE SYSTEMS

    Microsoft Academic Search

    Z Hu; M C Wentzel; G A Ekama

    SUMMARY A biological nutrient removal (BNR) activated sludge (AS) scheme incorporating external nitrification in a fixed media system is evaluated. A laboratory scale investigation of the scheme indicates that it holds considerable potential for BNRAS system intensification through major reduction in sludge age and oxygen demand and significant improvement in sludge settleability. Because the BNRAS system is not required to

  12. Measuring Cellular-Scale Nutrient Distribution in Algal Biofilms with

    E-print Network

    Dodds, Walter

    determine macroalgae (seaweed) cell-wall composition ap- most useful tools for the study of biological. Performing molecular spectroscopy through a mi- cells) research has grown. Primarily, cultured algae have nutrient dis- tribution in single algal cells on acellular and subcellular level. To enable the study

  13. Behavioural mechanisms of nutrient balancing in Locusta migratoria nymphs

    Microsoft Academic Search

    P. G. Chambers; S. J. Simpson; D. Raubenheimer

    1995-01-01

    This study addresses the short-term behavioural mechanisms that underlie nutrient balancing by a herbivorous insect. Fifth instar Locusta migratoria nymphs were given one of four pairings of artificial foods, with each food containing different levels of protein and carbohydrate. The foods were chosen such that the treatment groups would have to ingest very different ratios of the foods to attain

  14. Stream water nutrient enrichment in a mixed-use watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutrophic conditions, in both saline and freshwater systems, result from nutrient export from upstream watersheds. The objective of this study was to quantify the surface runoff losses of nitrate-nitrogen (NO3-N), total nitrogen (TN), dissolved reactive phosphorus (DRP), and total phosphorus (TP) r...

  15. Nutrient Dynamics in Flooded Wetlands. II: Model Application

    EPA Science Inventory

    In this paper we applied and evaluated the wetland nutrient model described in an earlier paper. Hydrologic and water quality data from a small restored wetland located on Kent Island, Maryland, which is part of the Delmarva Peninsula on the Eastern shores of the Chesapeake Bay...

  16. NUTRIENT SOLUTION CONCENTRATION AFFECTS GROWTH OF SUBIRRIGATED BEDDING PLANTS

    Microsoft Academic Search

    Jong-Goo Kang; Marc W. van Iersel

    2002-01-01

    To evaluate the effects of nutrient solution concentration on growth of alyssum [Lobularia maritima (L.) Desv. ‘New Carpet of Snow’], celosia (Celosia argentea L. ‘Gloria Scarlet’), dianthus (Dianthus chinensis L. ‘Telstar Crimson’), gomphrena (Gomphrena globosa L. ‘Gnome White’), stock [Matthiola incana (L.) R. Br ‘Special Mix’], and zinnia (Zinnia elegans Jacq. ‘Dreamland Mix’), we grew plants with five different concentrations

  17. Thresholds of ecosystem response to nutrient enrichment from fish aggregations.

    PubMed

    Layman, Craig A; Allgeier, Jacob E; Yeager, Lauren A; Stoner, Elizabeth W

    2013-02-01

    Biogeochemical hotspots can be driven by aggregations of animals, via excretion, that provide a concentrated source of limiting nutrients for primary producers. In a subtropical seagrass ecosystem, we characterized thresholds of ecological change associated with such hotspots surrounding artificial reef habitats. We deployed reefs of three sizes to aggregate fishes at different densities (and thus different levels of nutrient supply via excretion) and examined seagrass characteristics that reflect ecosystem processes. Responses varied as a function of reef size, with higher fish densities (on larger reefs) associated with more distinct ecological thresholds. For example, adjacent to larger reefs, the percentage of P content (%P) of seagrass (Thalassia testudinum) blades was significantly higher than background concentrations; fish densities on smaller reefs were insufficient to support sharp transitions in %P. Blade height was the only variable characterized by thresholds adjacent to smaller reefs, but lower fish densities (and hence, nutrient input) on smaller reefs were not sufficient for luxury nutrient storage by seagrass. Identifying such complexities in ecological thresholds is crucial for characterizing the extent to which biogeochemical hotspots may influence ecosystem function at a landscape scale. PMID:23691671

  18. Reducing nutrient losses in runoff from furrow irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Few studies have comprehensively examined nutrient losses in runoff from furrow-irrigated fields, but the rising cost of fertilizer and finite nature of the resource encourages further research. A 2-yr experiment measured runoff losses of sediment, particulate P and N, and dissolved NO3-N, NH4-N, K...

  19. Plant Leaf Residue Decomposition, Nutrient Release and Soil Enzyme Activity

    Microsoft Academic Search

    Julia Dux; Lindsey Norgrove; Stefan Hauser; Barbara Wick; Ronald Kühne

    We studied the impact of plant leaf residue decompo sition and nutrient release of nitrogen and phosphorus of two weed species - Imperata cylindrica and Chromolaena odorata - and one native forest species - Phyllanthus discoideus - on soil enzyme activities in a pot experiment in the humid tropics of central Cameroon. We tested th e impact of plant leaf

  20. IMPROVED SCIENCE AND DECISION SUPPORT FOR MANAGING WATERSHED NUTRIENT LOADS

    EPA Science Inventory

    The proposed research addresses two critical gaps in the TMDL process: (1) the inadequacy of presently existing receiving water models to accurately simulate nutrient-sediment-water interactions and fixed plants; and (2) the lack of decision-oriented optimization f...