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1

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

PubMed

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

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

2014-05-01

2

Engineering Properties of NPK Fertilizer Modified Soil  

E-print Network

NPK fertilizer is applied to the soil to modify its properties to give greater crop yield. These soil properties include: unit weight, void ratio, water content, and plasticity, tensile strength, compressibility, permeability and compact ability. Thus it becomes imperative to examine the engineering properties of NPK 20-10-5 fertilizer modified soils. Analysis of test results showed that the liquid limit, shrinkage limit, coefficient of permeability, and void ratio are decreased by the addition of fertilizer. It reduces the shear strength parameters of a soil. Therefore, NPK 20-10-5 fertilizer decreases the bearing capacity of soil and thereby increasing its erodibility

Ezeokonkwo J. C

3

N=1=NPK=KIMCHI=N  

E-print Network

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 ...

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

2006-01-01

4

Cultivo hidropônico de lisianto p ara flor de corte em sistema de fluxo laminar de nutrientes  

Microsoft Academic Search

Resumo - O objetivo deste trabalho foi avaliar as características produtivas e comerciais do cultivo de quatro cultivares de lisianto (Eustoma grandiflorum) em três soluções nutritivas em sistema de fluxo laminar de nutrientes (NFT). Utilizou-se o delineamento em blocos casualizados, em esquema fatorial 4x3, com três repetições. Os tratamentos foram compostos de quatro cultivares (Echo Champagne, Mariachi Pure White, Balboa

Alice Antonello; Londero Backes; José Geraldo Barbosa; Paulo Roberto Cecon; José Antonio Saraiva Grossi; Rogério Luiz Backes; Fernando Luiz Finger; Av. P. H. Rolfs

5

Effect of compost, nitrogen salts, and NPK fertilizers on methane oxidation potential at different temperatures.  

PubMed

The effects of compost, nitrogen salts, and nitrogen-phosphorous-potassium (NPK) fertilizers on the methane oxidation potential (MOP) of landfill cover soil at various temperatures were assessed. For this, we used batch assays conducted at 5°C, 15°C, and 25°C with microcosms containing landfill cover soil slurries amended with these elements. Results indicated variable impacts dependent on the type of amendment and the incubation temperature. For a given incubation temperature, MOP varied from one compost to another and with the amount of compost added, except for the shrimp/peat compost. With this latter compost, independent of the amount, MOP values remained similar and were significantly higher than those obtained with other composts. Amendment with most of the tested nitrogen salts led to similar improvements in methanotrophic activity, except for urea. MOP with NPK fertilizer addition was amongst the highest in this study; the minimum value obtained with NPK (20-0-20) suggested the importance of P for methanotrophs. MOP generally increased with temperature, and nutrient limitation became less important at higher temperatures. Overall, at each of the three temperatures tested, MOP with NPK fertilizer amendments provided the best results and was comparable to those observed with the addition of the shrimp/peat compost. The results of this study provide the first evidence of the following: (1) compost addition to improve methanotrophic activity in a landfill cover soil should consider the amount and type of compost used and (2) the importance of using NPK fertilizers rather than nitrogen salts, in enhancing this activity, primarily at low temperatures. One can also consider the potential beneficial impact of adding these elements to enhance plant growth, which is an advantage for MOP. PMID:21894478

Jugnia, Louis-B; Mottiar, Yaseen; Djuikom, Euphrasie; Cabral, Alexandre R; Greer, Charles W

2012-03-01

6

Effect of NPK fertilizer on chemical composition of pumpkin (Cucurbita pepo Linn.) seeds.  

PubMed

An investigation of the proximate composition and antioxidant profile of pumpkin seeds obtained from different levels of NPK 15 : 15 : 15 compound fertilizer application at the Obafemi Awolowo University, Ile-Ife, Nigeria was carried out. Pumpkin seeds were grown in 2010 for two cropping seasons (May to August and August to November), and the following fertilizer rates were applied: 0, 50, 100, 150, 200, and 250 kg/ha. Standard analytical methods were used to determine protein, crude fibre, ash, fat, carbohydrate, antioxidant activities, phenol, flavonoid, proanthocyanidin, and anthocyanin. The highest concentrations of the proximate and antioxidants analysed were found from the seeds of control and those treated with lower NPK rates. The mean protein, ash, crude fibre, and carbohydrate values of pumpkin seeds at zero to 100 kg NPK/ha were 27%, 1.56%, 0.56%, and 11.7% respectively. At these same levels of fertilizer, pumpkin seed oil yield was 59%. Antioxidant activities ranged from 89.9 to 90.4% while total phenol was 47 mg/100 g. Except for carbohydrate, the % concentration of nutrients and antioxidants in pumpkin seeds was significantly (P = 0.05) depressed with fertilizer rates above 100 g/ha. PMID:22629204

Oloyede, F M; Obisesan, I O; Agbaje, G O; Obuotor, E M

2012-01-01

7

Effect of NPK Fertilizer on Chemical Composition of Pumpkin (Cucurbita pepo Linn.) Seeds  

PubMed Central

An investigation of the proximate composition and antioxidant profile of pumpkin seeds obtained from different levels of NPK 15?:?15?:?15 compound fertilizer application at the Obafemi Awolowo University, Ile-Ife, Nigeria was carried out. Pumpkin seeds were grown in 2010 for two cropping seasons (May to August and August to November), and the following fertilizer rates were applied: 0, 50, 100, 150, 200, and 250?kg/ha. Standard analytical methods were used to determine protein, crude fibre, ash, fat, carbohydrate, antioxidant activities, phenol, flavonoid, proanthocyanidin, and anthocyanin. The highest concentrations of the proximate and antioxidants analysed were found from the seeds of control and those treated with lower NPK rates. The mean protein, ash, crude fibre, and carbohydrate values of pumpkin seeds at zero to 100?kg NPK/ha were 27%, 1.56%, 0.56%, and 11.7% respectively. At these same levels of fertilizer, pumpkin seed oil yield was 59%. Antioxidant activities ranged from 89.9 to 90.4% while total phenol was 47?mg/100?g. Except for carbohydrate, the % concentration of nutrients and antioxidants in pumpkin seeds was significantly (P = 0.05) depressed with fertilizer rates above 100?g/ha. PMID:22629204

Oloyede, F. M.; Obisesan, I. O.; Agbaje, G. O.; Obuotor, E. M.

2012-01-01

8

Phosphate solubilizers enhance NPK fertilizer use efficiency in rice and legume cultivation.  

PubMed

It has been reported that phosphate solubilizing bacteria (PSB) are the most promising bacteria among the plant growth promoting rhizobacteria (PGPR); which may be used as biofertilizers for plant growth and nutrient use efficiency. Moreover, these soil micro-organisms play a significant role in regulating the dynamics of organic matter decomposition and the availability of plant nutrients such as nitrogen (N), phosphorus (P), potassium (K) and other nutrients. Through this study, the management of nutrient use efficiency by the application of PSB was targeted in order to make the applied nutrients more available to the plants in the rice (Oryza sativa) and yardlong bean (Vigna unguiculata) cultivation. Results have shown that the treatments with PSB alone or in the form of consortia of compatible strains with or without the external application of chemical NPK gave more germination index (G. I.) from 2.5 to 5 in rice and 2.7 to 4.8 in bean seeds. They also showed a higher growth in both shoot and root length and a higher biomass as compared to the control. This gives us an idea about the potentiality of these PSB strains and their application in rice and yardlong bean cultivation to get a better harvest index. Their use will also possibly reduce the nutrient runoff or leaching and increase in the use efficiency of the applied fertilizers. Thus, we can conclude that the NPK uptake and management can be improved by the use of PSB in rice and yardlong bean cultivation, and their application may be much more beneficial in the agricultural field. PMID:22558541

Duarah, I; Deka, M; Saikia, N; Deka Boruah, H P

2011-12-01

9

Comparative effectiveness of cattle manure, poultry manure, phosphocompost and fertilizer-NPK on three cropping systems in vertisols of semi-arid tropics. I. Crop yields and system performance.  

PubMed

A field experiment was conducted on deep vertisols of Bhopal, India to evaluate the manural potential of three organic manures: farmyard manure (FYM), poultry manure (PM), phosphocompost (PC) vis-a-vis 0%, 75% and 100% recommended dose of fertilizer-NPK and to find out the most productive cropping system at various combinations of organic manures and chemical fertilizers. The seed yield of intercrop soybean (population converted to 100%) was 8.7% less than sole soybean whereas the grain yield of intercrop sorghum was 9.5% more than that of sole sorghum. However, the productivity in terms of soybean equivalent yield (SEY) was relatively high in intercropping system. The increasing NPK dose from 0% to 100% significantly improved SEY in sole sorghum and soybean/sorghum intercropping system and the integrated use of organics and inorganics recorded significantly more SEY than inorganics. The effect of nutrient management followed the order; 75% NPK + 5 t FYM ha(-1) > 75% NPK + 1.5 t PM ha(-1) > 75% NPK + 5 t PC ha(-1) > 100% NPK. Sorghum, both as sole and intercrop, responded more to PM while soybean to FYM. Application of 75% NPK in combination with PM or FYM or PC to preceding rainy season crops (soybean and sorghum) and 75% NPK to wheat produced significantly higher grain yield of wheat than those in inorganics and control indicating noticeable residual effect on the succeeding wheat crop and saving of 25% fertilizer-NPK. The effect of PC on rainy season crops was not as prominent as those of FYM and PM, but its residual effect on grain yield of wheat was comparable to those two organic manures. Among the cropping systems, soybean as preceding crop recorded the highest seed yield of wheat and was on a par with that of soybean/sorghum intercropping system. The yield of wheat following sorghum was the lowest. The total system productivity (TSP) was the highest in sorghum + soybean-wheat system and the lowest in the soybean-wheat system. PMID:15207299

Ghosh, P K; Ramesh, P; Bandyopadhyay, K K; Tripathi, A K; Hati, K M; Misra, A K; Acharya, C L

2004-10-01

10

Nutrients & Diagnosing Nutrient Needs  

E-print Network

Organic matter decomposition Weathering of soil minerals and rocks Atmosphere & precipitation OrganicNutrients & Diagnosing Nutrient Needs Carrie Laboski Dept. of Soil Science UW-Madison #12;Sources of nutrients available for plant uptake Nutrients in the soil solution are: In ionic form At low

Balser, Teri C.

11

Slow-released NPK fertilizer encapsulated by NaAlg-g-poly(AA-co-AAm)/MMT superabsorbent nanocomposite.  

PubMed

A novel slow released NPK fertilizer encapsulated by superabsorbent nanocomposite was prepared via in-situ free radical polymerization of sodium alginate, acrylic acid, acrylamide, and montmorillonite in the presence of fertilizer compounds. Evidence of grafting and component interactions, superabsorbent nanocomposite structure and morphology was obtained by a FT-IR, XRD and SEM techniques. The water absorbency behavior of superabsorbent nanocomposite was investigated. After those characterizations, the potential application was verified through the study of fertilizer release from prepared formulations. Results indicated that the presence of the montmorillonite caused the system to liberate the nutrient in a more controlled manner than that with the neat superabsorbent. The good slow release fertilizer property as well as good water retention capacity showed that this formulation is potentially viable for application in agriculture as a fertilizer carrier vehicle. PMID:25263891

Rashidzadeh, Azam; Olad, Ali

2014-12-19

12

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

PubMed

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

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

13

Wheat (Triticum aestivum L.) response to a zinc fertilizer applied as zinc lignosulfonate adhered to a NPK fertilizer.  

PubMed

The efficacy as Zn fertilizers for wheat of zinc lignosulfonate (ZnLS) products adhered to NPK was evaluated by three plant experimental designs. In the first and second assays, wheat plants were grown under controlled conditions with perlite and a calcareous soil as substrate, respectively. Shoot dry matter and Zn concentration showed that NPK + ZnLS was a better Zn source for wheat than NPK + ZnSO(4) under our experimental conditions. A third experiment was conducted under field conditions on a calcareous soil with a low Zn level. Wheat samples were taken at five growth stages of the crop. Although at early stages NPK + ZnLS was the most efficient source of Zn, at harvest no significant differences among treatments were found. Despite that, NPK + ZnLS showed evidence of being a useful Zn source for wheat crop under calcareous conditions. PMID:20527916

Martín-Ortiz, Diego; Hernández-Apaolaza, Lourdes; Gárate, Agustín

2010-07-14

14

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

Microsoft Academic Search

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

Abdeslam Ennabili; Mohammed Ater; Michel Radoux

1998-01-01

15

Modification in growth, biomass and yield of radish under supplemental UV-B at different NPK levels  

Microsoft Academic Search

Growth, biomass, yield and quality characteristics of radish (Raphanus sativus L. var. Pusa Himani) were investigated under supplemental UV-B (sUV-B; 280–320nm; +7.2kJm?2d?1) radiation at varying levels of soil NPK. Combinations of NPK were recommended, 1.5 times NPK, 1.5 times N and 1.5 times K. sUV-B radiation negatively affected the growth and economic yield with more reductions at 1.5 times recommended

Suruchi Singh; Rima Kumari; Madhoolika Agrawal; S. B. Agrawal

2011-01-01

16

Soil nutrients trump intraspecific effects on understory plant communities.  

PubMed

Understanding the links between intraspecific genetic variation and patterns of diversity in associated communities has been the primary focus of community genetics or 'genes-to-ecosystem' research in ecology. While other ecological factors, such as the abiotic environment, have well-documented influences on communities, the relative contributions of genetic variation versus the environment to species interactions remains poorly explored. In this study, we use a common garden experiment to study a coastal dune plant community dominated by the shrub, Baccharis pilularis, which displays a morphological dimorphism in plant architecture. We found the differences in the understory plant community between erect and prostrate morphs of Baccharis to be statistically significant, but small relative to the impacts of nutrient additions (NPK and C additions), for the richness, cover, and biomass of the understory plant community. There were no significant interactions between Baccharis morphology and nutrient-addition treatments, suggesting the influence of nutrient addition was consistent between erect and prostrate morphs. Moreover, we found no difference in overall plant community composition between Baccharis morphs, while NPK additions led to shifts in understory community composition compared to unfertilized shrubs. In sum, our results indicate that nutrients are the more important factor governing understory plant community structure in a coastal dunes ecosystem followed by intraspecific variation in dominant shrub architecture. Our results address a growing call to understand the extended consequences of intraspecific variation across heterogeneous environments in terrestrial ecosystems. PMID:23851987

Crutsinger, Gregory M; Carter, Benjamin E; Rudgers, Jennifer A

2013-12-01

17

Effect of urea and certain NPK fertilizers on the cereal cyst nematode (Heterodera avenae) on wheat  

PubMed Central

Two outdoor pot experiments were conducted in two consecutive years under outdoor conditions during the wheat growing season in Saudi Arabia to determine the effects of urea and certain compound fertilizers (NPK), compared to the effects of the nematicide fenamiphos on the cereal cyst nematode (CCN), Heterodera avenae, and wheat growth. The results showed that all of the treatments, except the fertilizer diammonium phosphate (DAP), reduced the number of nematode cysts/root system and increased (P ? 0.05) the dry weight of nematode-infected wheat plants. Fenamiphos and urea resulted in the best control, followed by the NPK fertilizers. The combined application of urea and fenamiphos resulted in the most significant effect in decreasing (P ? 0.05) the number of cysts/root system and increasing (P ? 0.05) the growth of nematode-infected wheat plants. PMID:24600314

Al-Hazmi, Ahmad S.; Dawabah, Ahmed A.M.

2013-01-01

18

Efficiency of a NPK fertilizer with adhered zinc lignosulfonate as a zinc source for maize (Zea mays L.).  

PubMed

The aim of this work was to evaluate the efficiency of a NPK fertilizer (8:15:15) with a Zn lignosulfonate (ZnLS) adhered as Zn source for maize plants. This product was compared in three experimental designs with the same NPK fertilizer with ZnSO(4) adhered and with no Zn adhered. The first and the second assays were carried out in a growth chamber by using perlite and a calcareous soil as substrate and the third experiment was raised in two calcareous fields. In general, growth chamber experiments showed that plants treated with NPK + ZnLS presented the highest dry weight and Zn concentrations in shoots. Also at field experiments, the Zn concentration in shoots was significantly high in plants treated with NPK + ZnLS. The grain harvested showed that this treatment gave the highest values in one location, but in the other no significant differences were observed. Although further research is required, we can conclude that NPK + ZnLS product could be a suitable source of Zn for maize crops. PMID:19761209

Martín-Ortiz, Diego; Hernández-Apaolaza, Lourdes; Gárate, Agustín

2009-10-14

19

Influence of NPK fertilization on calcium and magnesium in Poa pratensis L. with reference to dietary requirements of grazing cattle  

Microsoft Academic Search

A two?year experiment was conducted on Edwards muck (Limnic Medisaprist) on the Pinney?Purdue Agricultural Center at Wanatah, Indiana to study the effect of NPK fertilization on Ca and Mg concentrations in Kentucky bluegrass (Poa pratensis L.). Eight combinations of N?P?K fertilizer (0–0–0, 0–99–0, 0–0–372, 0–99–372, 168–0–0, 168–99–0, 168–0–372, 168–99–372 kg\\/ha), were applied each spring. Four cuttings were taken annually during

J. W. Lightner; C. L. Rhykerd; D. B. Mengel; G. E. Van Scoyoc; E. L. Hood; C. H. Noller

1983-01-01

20

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

Microsoft Academic Search

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

Veiko Uri; Hardi Tullus; Krista Lõhmus

2002-01-01

21

Differential sensitivity of spinach and amaranthus to enhanced UV-B at varying soil nutrient levels: association with gas exchange, UV-B-absorbing compounds and membrane damage.  

PubMed

The metabolic reasons associated with differential sensitivity of C3 and C4 plant species to enhanced UV-B under varying soil nutrient levels are not well understood. In the present study, spinach (Spinacia oleracea L. var All Green), a C3 and amaranthus (Amaranthus tricolor L. var Pusa Badi Chaulai), a C4 plant were subjected to enhanced UV-B (280-315 nm; 7.2 kJ m(-2) day(-1)) over ambient under varying soil nutrient levels. The nutrient amendments were recommended Nitrogen (N), Phosphorus (P), Potassium (K), 1.5× recommended NPK, 1.5× recommended N and 1.5× recommended K. Enhanced UV-B negatively affected both the species at all nutrient levels, but the reductions varied with nutrient concentration and combinations. Reductions in photosynthetic rate, stomatal conductance and chlorophyll content were significantly more in spinach compared with amaranthus. The reduction in photosynthetic rate was maximum at 1.5× recommended K and minimum in 1.5× NPK amended plants. The oxidative damage to membranes measured in terms of malondialdehyde content was significantly higher in spinach compared with amaranthus. Enhanced UV-B reduced SOD activity in both the plants except in amaranthus at 1.5× recommended K. POX activity increased under enhanced UV-B at all nutrient levels in amaranthus, but only at 1.5× K in spinach. Amaranthus had significantly higher UV-B-absorbing compounds than spinach even under UV-B stress. Lowest reductions in yield and total biomass under enhanced UV-B compared with ambient were observed in amaranthus grown at 1.5× recommended NPK. Enhanced UV-B did not significantly change the nitrogen use efficiency in amaranthus at all NPK levels, but reduced in spinach except at 1.5× K. These findings suggest that the differential sensitivity of the test species under enhanced UV-B at varying nutrient levels is due to varying antioxidative and UV-B screening capacity, and their ability to utilize nutrients. Amaranthus tolerated enhanced UV-B stress more than spinach at all nutrient levels and 1.5× recommended NPK lowered the sensitivity maximally to enhanced UV-B with respect to photosynthesis, biomass and yield. PCA score has also confirmed the lower sensitivity of amaranthus compared with spinach with respect to the measured physiological and biochemical parameters. PMID:23686471

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

2013-07-01

22

Nutrient uptake in mycorrhizal symbiosis  

Microsoft Academic Search

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

H. Marschner

1994-01-01

23

Key Nutrients.  

ERIC Educational Resources Information Center

Lessons written to help trainer agents prepare aides for work with families in the Food and Nutrition Program are presented in this booklet. The key nutrients discussed in the 10 lessons are protein, carbohydrates, fat, calcium, iron, iodine, and Vitamins A, B, C, and D. the format of each lesson is as follows: Purpose, Presentation, Application…

Federal Extension Service (USDA), Washington, DC.

24

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.

2010-02-09

25

Clinicopathologic findings in goats exposed to drinking water experimentally contaminated with varied low percentages of NPK 15–15–15 fertilizer  

Microsoft Academic Search

This study investigated the clinicopathology of goats exposed to drinking water experimentally contaminated with varied low\\u000a percentages of NPK 15–15–15 fertilizer. Twenty West African dwarf (WAD) goats of between 4 and 8 months of age were used for\\u000a the study. They were randomly divided into four groups (A, B, C, and D) and were given drinking water contaminated with NPK\\u000a 15–15–15

John I. Ihedioha; Christian O. Okorie-Kanu

2011-01-01

26

Impact of commercial garden growth substratum and NPK-fertilizer on copper fractionation in a copper-mine tailing  

Microsoft Academic Search

Organic amendment and NPK-fertilizer could affect the distribution of copper (Cu) among Cu-mine tailing compounds and hence the availability or phytotoxicity of Cu to plants. A laboratory incubation experiment was conducted to investigate the forms of Cu in a Cu-mine tailing (pH 7.70) amended with a commercial garden growth substratum (GGS) containing peat moss and natural mycorrhizae (Glomus intraradices) in

A. Charles; A. Karam; A. Jaouich

2009-01-01

27

Forbidden Lines in ns2npk Ground Configurations and nsnp Excited Configurations of Beryllium through Molybdenum Atoms and Ions  

Microsoft Academic Search

Observed and predicted wavelengths of magnetic dipole lines arising within ground configurations of the type ns2npk(n=2 and 3, k=1 to 5) are compiled. For n=2 the compilation includes the elements B through Kr, and for k=5 it extends to Mo. For n=3 Al through Mo are included. In addition the 2s2p excited configuration of the Be i isoelectronic sequence for

Victor Kaufman; Jack Sugar

1986-01-01

28

Effect of N and NPK fertilizers on early field performance of narrow-leaved ash, Fraxinus angustifolia.  

PubMed

The effect of fertilization in the first growing season on early survival and growth of narrow-leaved ash (NLA) (Fraxinus angustifolia ssp. oxycarpa) was evaluated throughout the first 3 years of growth in Adapazari, Turkey. A randomized complete block design with four replications was established to investigate fertilization effects. Granular N urea [46%, (NH2)2CO, NH2-N] and NPK (15/15/15%; NH3-N, P2O5, K2O) fertilizers were applied in mid-May of the first growing season. Fertilization treatments per tree were control, 67 g NPK (equal to 10/10/10 g N/P2O5 /K2O tree(-1)), 133 g NPK (20/20/20 g N/P2O5 /K2O tree(-1)), 33 g urea N (15 g N tree(-1)) and 54 g urea N (25 g N tree(-1)). After three growing seasons under these fertilizer treatments, 98% of trees were still viable. Compared to the control treatment, fertilization had a large and positive effect on diameter and height growth during the first 3 years of growth. However, since there were no significant differences among the fertilized plots in terms of tree diameter and height growth, addition of P and K to the fertilizer regime was not beneficial. The results show that N fertilization in the first growing season has the potential to improve early field growth of narrow-leaved ash. PMID:20648820

Cicek, Emrah; Yilmaz, Faruk; Yilmaz, Murat

2010-01-01

29

Short-term effect of nutrient availability and rainfall distribution on biomass production and leaf nutrient content of savanna tree species.  

PubMed

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna to test how water supply (even water supply vs. natural rainfall) and nutrient availability (no fertilisation vs. fertilisation) affects seedlings' above-ground biomass production and leaf-nutrient concentrations (N, P and K) of broad-leafed and fine-leafed tree species. Contrary to expectations, neither changes in water supply nor changes in soil nutrient level affected biomass production of the studied species. By contrast, leaf-nutrient concentration did change significantly. Under regular water supply, soil nutrient addition increased the leaf phosphorus concentration of both fine-leafed and broad-leafed species. However, under uneven water supply, leaf nitrogen and phosphorus concentration declined with soil nutrient supply, this effect being more accentuated in broad-leafed species. Leaf potassium concentration of broad-leafed species was lower when growing under constant water supply, especially when no NPK fertilizer was applied. We found that changes in environmental factors can affect leaf quality, indicating a potential interactive effect between land-use changes and environmental changes on savanna vegetation: under more uneven rainfall patterns within the growing season, leaf quality of tree seedlings for a number of species can change as a response to changes in nutrient levels, even if overall plant biomass does not change. Such changes might affect herbivore pressure on trees and thus savanna plant community dynamics. Although longer term experiments would be essential to test such potential effects of eutrophication via changes in leaf nutrient concentration, our findings provide important insights that can help guide management plans that aim to preserve savanna biodiversity. PMID:24667837

Barbosa, Eduardo R M; Tomlinson, Kyle W; Carvalheiro, Luísa G; Kirkman, Kevin; de Bie, Steven; Prins, Herbert H T; van Langevelde, Frank

2014-01-01

30

Short-Term Effect of Nutrient Availability and Rainfall Distribution on Biomass Production and Leaf Nutrient Content of Savanna Tree Species  

PubMed Central

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna to test how water supply (even water supply vs. natural rainfall) and nutrient availability (no fertilisation vs. fertilisation) affects seedlings’ above-ground biomass production and leaf-nutrient concentrations (N, P and K) of broad-leafed and fine-leafed tree species. Contrary to expectations, neither changes in water supply nor changes in soil nutrient level affected biomass production of the studied species. By contrast, leaf-nutrient concentration did change significantly. Under regular water supply, soil nutrient addition increased the leaf phosphorus concentration of both fine-leafed and broad-leafed species. However, under uneven water supply, leaf nitrogen and phosphorus concentration declined with soil nutrient supply, this effect being more accentuated in broad-leafed species. Leaf potassium concentration of broad-leafed species was lower when growing under constant water supply, especially when no NPK fertilizer was applied. We found that changes in environmental factors can affect leaf quality, indicating a potential interactive effect between land-use changes and environmental changes on savanna vegetation: under more uneven rainfall patterns within the growing season, leaf quality of tree seedlings for a number of species can change as a response to changes in nutrient levels, even if overall plant biomass does not change. Such changes might affect herbivore pressure on trees and thus savanna plant community dynamics. Although longer term experiments would be essential to test such potential effects of eutrophication via changes in leaf nutrient concentration, our findings provide important insights that can help guide management plans that aim to preserve savanna biodiversity. PMID:24667837

Barbosa, Eduardo R. M.; Tomlinson, Kyle W.; Carvalheiro, Luisa G.; Kirkman, Kevin; de Bie, Steven; Prins, Herbert H. T.; van Langevelde, Frank

2014-01-01

31

Seasonal Branch Nutrient Dynamics in Two Mediterranean Woody Shrubs with Contrasted Phenology  

PubMed Central

• Background and aims Mediterranean woody plants have a wide variety of phenological strategies. Some authors have classified the Mediterranean phanaerophytes into two broad phenological categories: phenophase?overlappers (that overlap resource?demanding activities in a short period of the year) and phenophase?sequencers (that protract resource?demanding activities throughout the year). In this work the impact of both phenological strategies on leaf nutrient accumulation and retranslocation dynamics at the level of leaves and branches was evaluated. Phenophase?overlappers were expected to accumulate nutrients in leaves throughout most of the year and withdraw them efficiently in a short period. Phenophase?sequencers were expected to withdraw nutrients progressively throughout the year, without long accumulation periods. • Methods To test this hypothesis, variations in phenology and leaf NPK in the crown of a phenophase?overlapper Cistus laurifolius and a phenophase?sequencer Bupleurum fruticosum were monitored monthly during 2 years. • Key Results Changes in nutrient concentration at the leaf level were not clearly related with the different phenologies. Nitrogen and phosphorous resorption efficiencies were lower in the phenophase?overlapper, and accumulation–retranslocation seasonality was similar in both species. Changes in the branch nutrient pool agreed with the hypothesis that the phenophase?overlapper accumulated nutrients from summer until the bud burst of the following spring, recovering a large nutrient pool during massive leaf shedding. The phenophase?sequencer did not accumulate nutrients from autumn until early spring, achieving lower nutrient recovery during spring leaf shedding. • Conclusions It is concluded that phenological demands influence branch nutrient cycling. This effect is easier to detect by assessing changes in the branch nutrient pool rather than changes in the leaf nutrient concentration. PMID:15072979

MILLA, RUBÉN; MAESTRO?MARTÍNEZ, M.; MONTSERRAT?MARTÍ, G.

2004-01-01

32

Chemical evaluation of nutrient supply from fly ash-biosolids mixtures  

SciTech Connect

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.

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

2000-02-01

33

Differential response of radish plants to supplemental ultraviolet-B radiation under varying NPK levels: chlorophyll fluorescence, gas exchange and antioxidants.  

PubMed

Current and projected increases in ultraviolet-B (UV-B; 280-315 nm) radiation may alter crop growth and yield by modifying the physiological and biochemical functions. This study was conducted to assess the possibility of alleviating the negative effects of supplemental UV-B (sUV-B; 7.2 kJ m?² day?¹; 280-315 nm) on radish (Raphanus sativus var Pusa Himani) by modifying soil nitrogen (N), phosphorus (P) and potassium (K) levels. The N, P and K treatments were recommended dose of N, P and K, 1.5 times recommended dose of N, P and K, 1.5 times recommended dose of N and 1.5 times recommended dose of K. Plants showed variations in their response to UV-B radiation under varying soil NPK levels. The minimum damaging effects of sUV-B on photosynthesis rate and stomatal conductance coupled with minimum reduction in chlorophyll content were recorded for plants grown at recommended dose of NPK. Flavonoids increased under sUV-B except in plants grown at 1.5 times recommended dose of N. Lipid peroxidation (LPO) also increased in response to sUV-B at all NPK levels with maximum at 1.5 times recommended dose of K and minimum at recommended dose of NPK. This study revealed that sUV-B radiation negatively affected the radish plants by reducing the photosynthetic efficiency and increasing LPO. The plants grown at 1.5 times recommended dose of NPK/N/K could not enhance antioxidative potential to the extent as recorded at recommended dose of NPK and hence showed more sensitivity to sUV-B. PMID:22304244

Singh, Suruchi; Kumari, Rima; Agrawal, Madhoolika; Agrawal, Shashi Bhushan

2012-07-01

34

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

PubMed

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

Lou, Y; Yang, Y

2001-04-01

35

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

PubMed

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

Wu, Lan; Liu, Mingzhu; Rui Liang

2008-02-01

36

Root nutrient foraging.  

PubMed

During a plant's lifecycle, the availability of nutrients in the soil is mostly heterogeneous in space and time. Plants are able to adapt to nutrient shortage or localized nutrient availability by altering their root system architecture to efficiently explore soil zones containing the limited nutrient. It has been shown that the deficiency of different nutrients induces root architectural and morphological changes that are, at least to some extent, nutrient specific. Here, we highlight what is known about the importance of individual root system components for nutrient acquisition and how developmental and physiological responses can be coupled to increase nutrient foraging by roots. In addition, we review prominent molecular mechanisms involved in altering the root system in response to local nutrient availability or to the plant's nutritional status. PMID:25082891

Giehl, Ricardo F H; von Wirén, Nicolaus

2014-10-01

37

Biogeochemical nutrient cycles and nutrient management strategies  

Microsoft Academic Search

Nutrient loading by riverine input into estuarine systems has increased by 6–50 times for the N load from pristine conditions to present, whereas a 18–180 times increase has been observed in the P load. Reductions in the ratio of N to P delivery has also occurred with time. In a review of nutrient limitation in estuarine systems, it is shown

Daniel J. Conley

1999-01-01

38

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

Microsoft Academic Search

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

Arshad Javaid; Rukhsana Bajwa

2011-01-01

39

Estimating nutrient surplus and nutrient use efficiency from farm characteristics  

Microsoft Academic Search

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

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

1995-01-01

40

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

SciTech Connect

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.

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

1989-01-01

41

Yield trends, and changes in soil organic-C and available NPK in a long-term rice–wheat system under integrated use of manures and fertilisers  

Microsoft Academic Search

Rice–wheat rotations, practised in 12.5million ha in Indo-Gangetic Plain region (IGPR), are the most important production system for food security of south Asian countries. Recent reports, however, indicate that the system is under production fatigue as yields have started declining due to continuous rice–wheat cultivation. We analysed the yield trends and effect of fertiliser NPK application, alone or in combination

R. L Yadav; B. S Dwivedi; Kamta Prasad; O. K Tomar; N. J Shurpali; P. S Pandey

2000-01-01

42

Nutrients in an Estuary  

NSDL National Science Digital Library

In this activity, learners model estuaries, artificially enriching both fresh and salt water samples with different amounts of nutrients and observing the growth of algae over several weeks. Learners relate their results to the phenomenon of algae blooms in estuaries. Learners then analyze data for different sites at the Guana Tolomato Matanzas National Estuarine Research Reserve (GTMNERR) in Florida to discover the relationships between nitrogen, chlorophyll, and dissolved oxygen. Finally, learners study how nutrients cycle through an estuary and suggest recommendations for reducing nutrient inputs to estuary waters.

Terc; National Oceanic and Atmospheric Administration (NOAA)

2012-06-26

43

LAKE NUTRIENT MODELING STUDY  

EPA Science Inventory

Determining the effects of morphological conditions, turbidity and watershed land use / land cover patterns on nutrient levels in Central Plains lakes and reservoirs. The study involves intensive field monitoring for the calibration and verification of basin and watershed models...

44

Food Groups and Nutrients  

NSDL National Science Digital Library

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 ...

Perry, Miss

2007-11-08

45

Nutrient cycling and foodwebs in Dutch estuaries  

Microsoft Academic Search

In this review several aspects of the functioning of the Dutch estuaries (Ems-Dollard, Wadden Sea, Oosterschelde, Westerschelde,\\u000a Grevelingen and Veerse Meer) have been compared. A number of large European rivers (especially Rhine) have a prevailing influence\\u000a on the nutrient cycling of most Dutch estuaries. Owing to the increased loading of the estuaries with nitrogen and phosphorus\\u000a compounds, effects of eutrophication

P. H. Nienhuis

1993-01-01

46

The subtropical nutrient spiral  

NASA Astrophysics Data System (ADS)

We present an extended series of observations and more comprehensive analysis of a tracer-based measure of new production in the Sargasso Sea near Bermuda using the 3He flux gauge technique. The estimated annually averaged nitrate flux of 0.84 ± 0.26 mol m-2 yr-1 constitutes only that nitrate physically transported to the euphotic zone, not nitrogen from biological sources (e.g., nitrogen fixation or zooplankton migration). We show that the flux estimate is quantitatively consistent with other observations, including decade timescale evolution of the 3H + 3He inventory in the main thermocline and export production estimates. However, we argue that the flux cannot be supplied in the long term by local diapycnal or isopycnal processes. These considerations lead us to propose a three-dimensional pathway whereby nutrients remineralized within the main thermocline are returned to the seasonally accessible layers within the subtropical gyre. We describe this mechanism, which we call "the nutrient spiral," as a sequence of steps where (1) nutrient-rich thermocline waters are entrained into the Gulf Stream, (2) enhanced diapycnal mixing moves nutrients upward onto lighter densities, (3) detrainment and enhanced isopycnal mixing injects these waters into the seasonally accessible layer of the gyre recirculation region, and (4) the nutrients become available to biota via eddy heaving and wintertime convection. The spiral is closed when nutrients are utilized, exported, and then remineralized within the thermocline. We present evidence regarding the characteristics of the spiral and discuss some implications of its operation within the biogeochemical cycle of the subtropical ocean.

Jenkins, William J.; Doney, Scott C.

2003-12-01

47

Influence of Npk inorganic fertilizer treatment on the proximate composition of the leaves of Ocimum gratissimum (L.) and Gongronema latifolium (benth).  

PubMed

The influence of NPK inorganic fertilizer treatment on the proximate composition of the leaves of Ocimum gratissimum (L.) and Gongronema latifolium (Benth) was investigated. Cultivated O. gratissimum and G. latifolium were treated with NPK (15:15:15) fertilizer at 100, 200, 300, 400 and 500 kg h(-1) treatment levels in planting buckets derived using the furrow slice method two months after seedling emergence. No fertilizer treatment served as control. The leaves of the plants were harvested for analysis one month after treatment. The leaf was used for the analysis because it the most eaten part. Fertilizer treatment significantly (p < 0.05) increased the dry matter, moisture content, ash, crude protein, crude fibre, crude fat contents of the leaves of both plants. On the other hand, fertilizer treatment significantly, (p < 0.05) decreased the carbohydrate and the calorific value of the leaves of the plants. The increase in the concentrations of these substances as a result of fertilizer of fertilizer treatment might be due to the role of fertilizer in chlorophyll content of plant's leaves, which in turn enhanced the process of photosynthesis leading to increased synthesis of these substances. The decrease in the carbohydrate content might be due to its conversion to other materials in the plants. The results obtained were discussed in line with current literatures. PMID:24494518

Osuagwu, G G E; Edeoga, H O

2013-04-15

48

Ocean nutrient enhancer \\  

Microsoft Academic Search

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

Satoshi Masuda; Masayuki Yonezawa; Masao Morikawa

2004-01-01

49

Exploring estuarine nutrient susceptibility.  

PubMed

The susceptibility of estuaries to nutrient loading is an important issue that cuts across a range of management needs. We used a theory-driven but data-tested simple model to assist classifying estuaries according to their susceptibility to nutrients. This simple nutrient-driven phytoplankton model is based on fundamental principles of mass balance and empirical response functions for a wide variety of estuaries in the United States. Phytoplankton production was assumed to be stoichiometrically proportional to nitrogen load and an introduced "efficiency factor" intended to capture the myriad processes involved in converting nitrogen load to algal production. A Markov Chain Monte Carlo algorithm of Bayesian inference was then employed for parameter estimation. The model performed remarkably well for chlorophyll estimates, and the predicted estimates of primary production, grazing, and sinking losses are consistent with measurements reported in the literature from a wide array of systems. Analysis of the efficiency factor suggests that estuaries with the ratio of river inflow to estuarine volume (Q/V) greater than 2.0 per year are less susceptible to nutrient loads, and those with Q/V between 0.3 and 2.0 per year are moderately susceptible. This simple model analysis provides a first-order screening tool for estuarine susceptibility classification. PMID:19544842

Scavia, Donald; Liu, Yong

2009-05-15

50

Nutrient Requirements in Adolescence.  

ERIC Educational Resources Information Center

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…

McKigney, John I,; Munro, Hamish N.

51

Nutrient Sharing between Symbionts  

Microsoft Academic Search

In this review, we consider the exchange of nutrients between the host plant and the bacterial microsym- biont in nitrogen-fixing legume root nodules. During nodule formation, the host tissues and the bacterial microsymbiont develop in response to each other to formaspecializedtissuethatmaintains anenvironment where nitrogen fixation can occur (Brewin, 2004; Mergaert et al., 2006; Prell and Poole, 2006). This com- plex

James White; Jurgen Prell; Euan K. James; Philip Poole

2007-01-01

52

Nutrition: What are Nutrients?  

NSDL National Science Digital Library

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

2010-05-24

53

Urban nUtrient Urban nUtrient  

E-print Network

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

Liskiewicz, Maciej

54

Nutrient Needs at a Glance  

E-print Network

This publication defines nutritional terms and lists the nutrients, vitamins, minerals and electrolytes for which recommended dietary allowances have been established. Additional information is provided on the sources of these nutrients...

Bielamowicz, Mary K.

2003-02-10

55

CSREES Nutrient Management Working Meeting  

E-print Network

or "themes": · Animal Waste Management · Drinking Water and Human Health · Environmental RestorationWelcome CSREES Nutrient Management Working Meeting May 4 and 5, 2004 Atlanta, GA #12;University Objectives · Information Sharing Among States ­ Nutrient management regulations ­ Nutrient management

56

Nutrients In Chesapeake Bay  

NSDL National Science Digital Library

The Chesapeake Bay is the largest estuary in the US. Eleven rivers empty into the bay creating the Chesapeake Bay Watershed. From urban areas and cultivated fields in which wetlands were not preserved, runoff can run into the rivers unfiltered. This runoff can include nutrients that can cause uncontrolled growth of an abundance of algae which can eventually increase the turbidity of the river, not allowing light to reach the bottom of the river. This will result in the loss of sub-aquatic vegetation (SAV) as well as the organisms which rely on it for food and habitat. There are a variety of tests that can be conducted to determine the presence of algae in the rivers. Two of these tests include pH and turbidity. In this lesson which includes field work, students will measure water quality and use authentic satellite data to explore the effects of nutrients in the Chesapeake Bay and the rivers of its watershed.

57

Nutrients, neurodevelopment, and mood  

Microsoft Academic Search

Human neurodevelopment is the result of genetic and environmental interactions. This paper examines the role of prenatal nutrition\\u000a relative to psychiatric disorders and explores the relationship among nutrients, mood changes, and mood disorders. Epidemiologic\\u000a studies have found that adults who were born with a normal, yet low birth weight have an increased susceptibility to diseases\\u000a such as coronary heart disease,

Regina C. Casper

2004-01-01

58

USDA Nutrient Database for Standard Reference  

MedlinePLUS

... to the USDA National Nutrient Database for Standard Reference Find nutrient information on over 8,000 foods ... program, The USDA National Nutrient Database for Standard Reference, is maintained by the Nutrient Data Laboratory, Beltsville ...

59

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

E-print Network

of governmental and industrial organizations, including the Department for Environment, Food and Rural AffairsThe Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions High for Dairy Research, School of Agriculture, Policy and Development, University of Reading, Reading, Berkshire

Bequette, Brian J.

60

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

E-print Network

The Journal of Nutrition Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions Human that hyperglycemia during pregnancy was associated with altered breast milk immune factors. Human milk) or without (n = 16) GDM at wk 24­28 in pregnancy. Milk was analyzed for HMO abundances, protein

Gleeson, Joseph G.

61

Changes in nutrient dynamics throughout water transfers in a Tropical Forest and Pasture of Rondonia, Brazil  

NASA Astrophysics Data System (ADS)

The clearing of tropical forest in the Brazilian Amazon for cattle pasture since the 70s is a globally important land use change that has consequences for soil biogeochemical cycles. Generally, five to ten years after deforestation, pastures become degraded due to inadequate management practices. Development of strategies for restoration of low productivity pastures constitutes the main goal for Rondônia state. We analyzed the concentrations of the main nutrient of the biogeochemical cycles in three representative land uses at Fazenda Nova Vida, in central Rondônia (10o30'S, 62o30'W). The treatments were: (1) native forest; (2) pasture dominated by the forage grass Brachiaria brizantha but containing some weeds, under non- intensive management and; (3) a section of the same pasture that was subjected to tilling, replanting and fertilization (NPK + micronutrients) to eliminate weeds and improve grass productivity. Water samples from rain, throughfall, overland flow, tension lysimeter and zero-tension lysimeter (1.0 m soil depth), were collected during the rainy seasons from January to May of 2002 and 2003. The concentrations of C (DOC and DIC), inorganic-N (NH4+, NO3- and NO2-), Na+, K+, Mg2+, Ca2+, SO42- and Cl- were measured in all treatments. Rain water was dominated by the nutrients (NH4+, Na+, K+, Ca2+ and Cl-) and DOC. Forest throughfall was enriched in most of the elements. Concentrations of elements in the overland flow showed higher variations in the pasture and in the plowed pasture, however samples were not collected in forest. Soil solution waters (tension lysimeter) and lysimeter waters (zero-tension lysimeter) too had higher variations for elements concentrations in all treatments. Forest clearing for pasture and pasture submitted to tillage practices profoundly influence soil properties and, consequently, the nutrient availability in soil profiles. The soil solution composition may be indicative of altered patterns of nutrient availability in this land use change.

Piccolo, M. D.; Neill, C.; Krusche, A.; Laclau, J. P.; Cerri, C. C.

2006-12-01

62

Use of Select Nutrients to Foster Wellness.  

ERIC Educational Resources Information Center

Discusses how to be healthy through one's diet. Lists 20 nutrients necessary for one's well being and explains role of each nutrient. Describes how nutrients complement one another and asserts that the right combination of nutrients can sometimes substitute for medication. Also lists 20 diagnostic categories of problems and suggests nutrients to…

Cassel, Russell N.

1987-01-01

63

Nutrient Removal in Wastewater Treatment  

ERIC Educational Resources Information Center

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)

Shah, Kanti L.

1973-01-01

64

Nutrient Influences on Leaf Photosynthesis  

PubMed Central

The net rate of CO2 uptake for leaves of Gossypium hirsutum L. was reduced when the plants were grown at low concentrations of NO3-, PO42-, or K+. 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 CO2 uptake rate at low nutrient levels was due to a decrease in the CO2 conductance expressed per unit mesophyll cell wall area (gcellCO2). The use of gcellCO2 and nutrient levels expressed per unit of mesophyll cell wall provides a new means of assessing nutrient effects on CO2 uptake of leaves. PMID:16661231

Longstreth, David J.; Nobel, Park S.

1980-01-01

65

Nutrient removal from farm effluents.  

PubMed

The objectives of the study were: (i) to examine the efficiency of nutrient removal during the treatment of dairy farm effluent in a two-pond system, and (ii) to produce an inexpensive but effective nutrient trap which could be recycled as a nutrient source or soil mulch. The concentration of chemical oxygen demand (COD), biological oxygen demand (BOD), nitrogen (N), phosphorus (P) and potassium (K) in a two-pond system used to treat dairy farm effluent was monitored over a period of 7 months. The retention of nutrients by two porous materials was examined both in the laboratory batch (zeolite and bark) and pilot-scale field (bark) experiments. The results indicated that biological treatment of farm effluents using the two-pond system was not effective in the removal of nutrients, which are likely to become pollutant when discharged to waterways. Both the bark and zeolite materials were effective in the removal of N, P and K from effluent. These materials can be placed in the second (i.e., aerobic) pond to treat effluents, which can then be discharged to streams with minimum impact on water quality. The nutrient-enriched porous materials can be recycled as a source of nutrients and soil conditioner. PMID:15182831

Bolan, N S; Wong, L; Adriano, D C

2004-09-01

66

SOUTHERN REGION NUTRIENT MANAGEMENT PUBLICATIONS  

E-print Network

SOUTHERN REGION NUTRIENT MANAGEMENT PUBLICATIONS BY CROP Bermudagrass Corn Cotton Forages Forage Sugarcane Turfgrasses and Lawn Vegetables Wetlands Wheat BY STATE Alabama Arkansas Florida Georgia Kentucky.) #12;Cotton Managing Nitrogen Fertilization in Cotton (Texas) (Hons, F.) Correcting Nitrogen Based

67

Nutrient Sensing in Plant Meristems  

Microsoft Academic Search

Plants need nutrient to grow and plant cells need nutrient to divide. The meristems are the factories and cells that are left\\u000a behind will expand and differentiate. However, meristems are not simple homogenous entities; cells in different parts of the\\u000a meristem do different things. Positional cues operate that can fate cells into different tissue domains. However, founder\\/stem\\u000a cells persist in

Dennis Francis; Nigel G. Halford

2006-01-01

68

South CarolinaSouth Carolina Nutrient Management Rules,Nutrient Management Rules,  

E-print Network

South CarolinaSouth Carolina Nutrient Management Rules,Nutrient Management Rules, Regulations, andManure Production Poultry ­ 40% Cow ­ 48% Swine ­ 12% #12;Nutrient Management ofNutrient Management of Confined and certification of all confined animal producers prior to July 2004 #12;Nutrient Management Requirements

69

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

E-print Network

Nutrient-plankton models with nutrient recycling S. R.-J. Jang1 and J. Baglama2 1. Department recycling can actually stabilize the nutrient- plankton interaction. Keywords: instantaneous nutrient of nutrient-plankton interaction with dif- ferent complexity have been constructed and analyzed since

Baglama, James

70

Nutrient density: principles and evaluation tools.  

PubMed

Nutrient profiling is the technique of rating or classifying foods on the basis of their nutritional value. Foods that supply relatively more nutrients than calories are defined as nutrient dense. Nutrient profile models calculate the content of key nutrients per 100 g, 100 kcal, or per serving size of food. For maximum effectiveness, nutrient profile models need to be transparent, based on publicly accessible nutrient composition data, and validated against independent measures of a healthy diet. These rigorous scientific standards were applied to the development of the Nutrient-Rich Foods (NRF) family of nutrient profile models. First, the NRF models included nutrients to encourage as well as nutrients to limit. Second, NRF model performance was repeatedly tested against the Healthy Eating Index (HEI), an independent measure of a healthy diet. HEI values were calculated for participants in the 1999-2002 NHANES. Models based on 100 kcal and serving sizes performed better than those based on 100 g. Formulas based on sums and means performed better than those based on ratios. The final NRF9.3 index was based on 9 beneficial nutrients (protein; fiber; vitamins A, C, and E; calcium; iron; potassium; and magnesium) and on 3 nutrients to limit (saturated fat, added sugar, and sodium). Higher NRF9.3 scores were associated with lower energy density and more nutrient-rich diets. The nutrient density of foods, paired with a comprehensive program of consumer education, can become the foundation of dietary recommendations and guidelines. PMID:24646818

Drewnowski, Adam; Fulgoni, Victor L

2014-05-01

71

Nutrients in a calcareous soil affected by Cadmium  

Microsoft Academic Search

A calcareous soil (Haploxeroll calcic) was amended in two different forms according with the standard nutritional requirements of tomato plant. The treatments applied were: i) an organic fertilization applying sewage sludge (SS), ii) an inorganic fertilization (IN) using mineral fertilizers (NPK), and iii) a treatment called W where no fertilizer was applied. For each treatment, cadmium (Cd) pollution was added

Raul Moral; Jose Navarro Pedreño; Joaquin Moreno Caselles; Ignacio Gómez; Jorge Mataix Solera

1998-01-01

72

Effect of sequential applications of foliar nutrients, biofertilizers and sowing dates on the incidence of corn stem borers in Egypt.  

PubMed

In this study either early sown (May 1st) or lately sown (June 2nd) corn plants were treated with Phosphorin & Rhizobactrin as biofertilizers and sprayed with six selected foliar nutrients, i.e. Polymex; Greenzit SP100, Greenzit NPK, Potasin-F, Copper sulphate and Ascorbic acid; in mono-, bi-, and/or tri-sequential applications. Such practices were conducted to show their beneficial effects compared with the chemical treatment in checking the incidence of the stem borers and hence increasing the corn yield. The obtained results could be summarized in the following chief points: (a) the lately sown biofertilized plants showed somewhat higher levels of infestation than the early planted ones., (b) in general, spraying the biofertilized corn plants in both sowing dates with the tested foliar nutrients, significantly decreased the rate of the stem borers infestation than the untreated plants of control., (c) the foliar sprays of Greenzit NPK alone, bi- or tri-sequential applications of Potasin-F, Polymex, Ascorbic acid and Copper sulphate achieved considerable success in reducing larval numbers of the borers species. For example, in case of using the bi-sequential nutrients (Polymex/Ascorbic acid) the numbers were 1.2, 1.5 and 1.2 larvae/5 plants, whereas the numbers were 1.3, 1.0 and 0.7 larvae/5 plants as a result, of the tri-sequential applications (Potasin-F/Ascorbic acid/Polymex) for the pink stem borer, Sesamia cretica, (Led.), the purple lined borer, Chilo agamemnon, (Bels.), and the European corn borer Ostrinia nubilalis (Hb.), in respect, vs. 4.8, 4.5 and 2.9 larvae/5 plants for the same stem borers, respectively, in case of the untreated corn plants. In addition, the other trisequential applications (Polymex/ascorbic acid/Copper sulphate), (Potasin-F/Copper sulphate/ascorbic acid) and (Potasin-F/Copper sulphate/Polymex) reduced the stem borers infestation; (d) from the view point of the interaction effects of sowing dates and the tested foliar nutrients, it was found that the tri-sequential sprayings (Potasin-F/Copper sulphate/Polymex) and/or (Potasin-F/Copper sulphate/Ascorbic acid) have lowered the rate of the stem borers infestation to 3.3 and 3.3 and 5.7 and 4.3 larvae/5 plants for the tri-applications in the 1st and 2nd sowing dates, respectively. Such reductions in the levels of infestation led to an increase in the grain yield up to 6.9 and 7.2 and 5.4 and 5.8 ton/fed, for the early and lately sown corn plants, in respect, and (e) All the foliar nutrients, with no exception, proved to be efficient in managing the stem borers infestation as compared with the insecticide treatment using Polytrin. Although the chemical application had lowered the level of infestation to 2.3 and 5.7 larvae/5 plants in the 1st and 2nd sowing dates as compared with 9.7 and 14.7 larvae/5 untreated plants for the same sowing dates, lesser grain yield of 5.6 and 4.4 ton/fed. was obtained in the first and second dates of planting, successively, in comparison to the grain yield resulted from the tri-applications of Potasin-F/Copper sulphate with either Polymex or Ascorbic acid. The abovementioned results assured the profitable effects of using foliar nutrients as well as the biofertilizers for attaining healthy corn plants, which would be capable of tolerating the injury inflicted by the studied stem borers and compensating for the harmful effects of insects infestation, so high grain yields could be obtained than those of the untreated and/or the insecticide treated plants. PMID:12696416

Mesbah, H A; Mourad, A K; el-Nimr, Hanyiat M; el-Kady, Magda B; Haroun, Nagah S

2002-01-01

73

Nutrient enrichment of natural waters  

Microsoft Academic Search

Evidence is presented to show the numerous sources of nutrient enrichment of natural waters. Factors affecting soil and water losses and their relationship to water pollution are discussed. The value and use of soil maps in predicting potential areas of water pollution from runoff and erosion is discussed. Small scale maps of the world are used to show how soil

A. A. Klingebiel

1973-01-01

74

with Comprehensive Nutrient Management Plans  

E-print Network

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

Mukhtar, Saqib

75

Nutrient Management in Organic Production  

E-print Network

, septic waste prohibited #12;Soils and Plants ­ Authorized Methods and Materials (Minerals) · Agricultural inputs · Holistic- emphasis on soil building, soil health, crop rotation, nutrient recycling · Requires, labeling ­Assure consumers of consistent standards in growing and labeling · Effect of history

Balser, Teri C.

76

Nutrient partitioning during adolescent pregnancy  

Microsoft Academic Search

Human adolescent mothers have an increased risk of delivering low birth weight and premature infants with high mortality rates within the first year of life. Studies using a highly controlled adolescent sheep paradigm demonstrate that, in young growing females, the hierarchy of nutrient partitioning during pregnancy is altered to promote growth of the maternal body at the expense of the

Jacqueline Wallace; Deirdre Bourke; Patricia Da Silva; Raymond Aitken

2001-01-01

77

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)

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.

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

2009-04-01

78

21 CFR 107.10 - Nutrient information.  

...the following nutrients supplied by 100 kilocalories: Nutrients Unit of measurement Protein Grams. Fat Do. Carbohydrate Do. Water Do. Linoleic acid Milligrams. Vitamins: Vitamin A International units. Vitamin D...

2014-04-01

79

21 CFR 107.10 - Nutrient information.  

Code of Federal Regulations, 2012 CFR

...the following nutrients supplied by 100 kilocalories: Nutrients Unit of measurement Protein Grams. Fat Do. Carbohydrate Do. Water Do. Linoleic acid Milligrams. Vitamins: Vitamin A International units. Vitamin D...

2012-04-01

80

21 CFR 107.10 - Nutrient information.  

Code of Federal Regulations, 2011 CFR

...the following nutrients supplied by 100 kilocalories: Nutrients Unit of measurement Protein Grams. Fat Do. Carbohydrate Do. Water Do. Linoleic acid Milligrams. Vitamins: Vitamin A International units. Vitamin D...

2011-04-01

81

21 CFR 107.10 - Nutrient information.  

Code of Federal Regulations, 2013 CFR

...the following nutrients supplied by 100 kilocalories: Nutrients Unit of measurement Protein Grams. Fat Do. Carbohydrate Do. Water Do. Linoleic acid Milligrams. Vitamins: Vitamin A International units. Vitamin D...

2013-04-01

82

Agronomy Facts 60 NUTRIENT MANAGEMENT PLANNING  

E-print Network

impact of nutrients on the environment. Programs such as the Chesapeake Bay Program and the Nutrient as pollutants. The leaching of nitrogen through the soil can raise groundwater nitrate levels. In addition

Kaye, Jason P.

83

Wastewater Treatment with Plants in Nutrient Films.  

National Technical Information Service (NTIS)

The nutrient film technique (NFT) is a unique modification of a hydroponic plant growth system which utilizes plants growing on an impermeable surface. A thin film of water flowing through the extensive root system provides nutrients for plants and associ...

H. DeLancey-Pompe, J. J. Madras, R. M. Kabrick, W. J. Jewell, W. W. Clarkson

1983-01-01

84

Phytoplanktonic nutrient utilisation and nutrient signature in the Southern Ocean  

Microsoft Academic Search

The separation in Southern Ocean provinces of silicate excess at nitrate exhaustion and of nitrate excess at silicate exhaustion was already introduced by Kamykowski and Zentara (Kamykowski, D., Zentara, S.J., 1985. Nitrate and silicic acid in the world ocean: patterns and processes. Mar. Ecol. Prog. Ser. 26, 47–59; and Kamykowski, D., Zentara, S.J., 1989. Circumpolar plant nutrient covariation in the

L. Goeyens; M. Semeneh; M. E. M. Baumann; M. Elskens; D. Shopova; F. Dehairs

1998-01-01

85

Nutrient transport in the Humber rivers  

Microsoft Academic Search

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

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

86

Nutrient Management Program Personnel Resource List  

E-print Network

v.01.2013 Nutrient Management Program Personnel Resource List State Conservation Commission 2301 N Nutrient Management Program Director 717-705-3895 Email: fschneider@pa.gov Oversees the implementation of the Nutrient Management Program in Pennsylvania. Provides technical, administrative and programmatic guidance

Guiltinan, Mark

87

Nutrient Management Program Personnel Resource List  

E-print Network

v.03.2014 Nutrient Management Program Personnel Resource List State Conservation Commission 2301 N Nutrient & Odor Management Programs Director 717-705-3895 Email: fschneider@pa.gov Oversees the implementation of the Nutrient Management Program in Pennsylvania. Provides technical, administrative

Guiltinan, Mark

88

Nutrient Management Module No. 12 Water Quality  

E-print Network

Nutrient Management Module No. 12 Water Quality Considerations and Regulations by Susan Mc about water quality considerations and regulations. This module covers Rocky Mountain CCA Nutrient, the reader should: 1.Recognize nutrient impacts on different water bodies 2.Understand common water quality

Lawrence, Rick L.

89

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 ...

90

N-P-K balance in a milk production system on a C. nlemfuensis grassland and a biomass bank of P. purpureum CT115 clone  

Microsoft Academic Search

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

G. Crespo; I. Rodriguez; O. Martinez

2009-01-01

91

Biomass and nutrient allocation of sawgrass and cattail along a nutrient gradient in the Florida Everglades  

Microsoft Academic Search

Biomass and nutrient allocation in sawgrass (Cladium jamaicense Crantz) and cattail (Typha domingensis Pers.) were examined along a nutrient gradient in the Florida Everglades in 1994. This north to south nutrient gradient, created by discharging nutrient-rich agricultural runoff into the northern region of Water Conservatio ea 2A, was represented by three areas (impacted, transitional and reference). Contrasting changes of plant

S. L. Miao; F. H. Sklar

1997-01-01

92

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

93

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

E-print Network

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

Baglama, James

94

Automated nutrient analyses in seawater  

SciTech Connect

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)

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

1981-02-01

95

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

PubMed

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

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

2010-02-01

96

Plant Nutrient Phytoremediation Using Duckweed  

Microsoft Academic Search

\\u000a Over the last 40 years a great deal of research has been published on the use of duckweed to treat wastewater both from point\\u000a sources (feedlots, food processing plants) and from non-point sources. These plants can recover nutrients such as nitrogen\\u000a and phosphorus from contaminated waters in those agricultural practices. They can also remove or accumulate metals, radionuclides,\\u000a and other

Louis Landesman; Clifford Fedler; Runbin Duan

97

Rhizosphere priming: a nutrient perspective.  

PubMed

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

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

2013-01-01

98

Nutrient Management in Recirculating Hydroponic Culture  

NASA Technical Reports Server (NTRS)

There is an increasing need to recirculate and reuse nutrient solutions in order to reduce environmental and economic costs. However, one of the weakest points in hydroponics is the lack of information on managing the nutrient solution. Many growers and research scientists dump out nutrient solutions and refill at weekly intervals. Other authors have recommended measuring the concentrations of individual nutrients in solution as a key to nutrient control and maintenance. Dumping and replacing solution is unnecessary. Monitoring ions in solution is not always necessary; in fact the rapid depletion of some nutrients often causes people to add toxic amounts of nutrients to the solution. Monitoring ions in solution is interesting, but it is not the key to effective maintenance.

Bugbee, Bruce

2004-01-01

99

Regulation of Nutrient Transport across the Placenta  

PubMed Central

Abnormal fetal growth, both growth restriction and overgrowth, is associated with perinatal complications and an increased risk of metabolic and cardiovascular disease later in life. Fetal growth is dependent on nutrient availability, which in turn is related to the capacity of the placenta to transport these nutrients. The activity of a range of nutrient transporters has been reported to be decreased in placentas of growth restricted fetuses, whereas at least some studies indicate that placental nutrient transport is upregulated in fetal overgrowth. These findings suggest that changes in placental nutrient transport may directly contribute to the development of abnormal fetal growth. Detailed information on the mechanisms by which placental nutrient transporters are regulated will therefore help us to better understand how important pregnancy complications develop and may provide a foundation for designing novel intervention strategies. In this paper we will focus on recent studies of regulatory mechanisms that modulate placental transport of amino acids, fatty acids, and glucose. PMID:23304511

Lager, Susanne; Powell, Theresa L.

2012-01-01

100

Managing urban nutrient biogeochemistry for sustainable urbanization.  

PubMed

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

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

2014-09-01

101

Nutrient transports in a Swedish estuary  

NASA Astrophysics Data System (ADS)

Himmerfjärd is a Swedish estuary bordering on the Baltic. The estuary lacks astronomical tides and its circulation is driven by winds and freshwater runoff. Because of a tertiary sewage treatment plant located at its inner end, the estuary is becoming increasingly eutrophic. A field study was carried out for a 78-day period in late summer and early fall of 1977 to determine rates of nutrient transport and to construct nutrient budgets. Since physical parameters (current velocity, temperature, salinity, winds and water level changes) were measured more frequently than nutrients (phosphate, nitrate, nitrite and ammonium) it was necessary to develop a suitable method to calculate nutrient flux time series and net nutrient fluxes. Over the study period, Himmerfjärd imported phosphorus and exported nitrogen. Direction of nutrient fluxes and changes in flux direction were consistent with the structure of the baroclinic currents.

Wilmot, Wayne; Toll, Peter; Kjerfve, Björn

1985-08-01

102

Rhizosphere Priming: a Nutrient Perspective  

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

103

Nutrient limitation in Crater Lake, Oregon  

Microsoft Academic Search

Experiments were carried out to determine what nutrient (or nutrients) was primarily responsible for limiting phytoplankton\\u000a productivity in ultraoligotrophic Crater Lake. The experiments included in situ and laboratory nutrient addition bioassays\\u000a utilizing the natural phytoplankton community, Selenastrum capricornutum bottle assays, photosynthetic responses, photosynthetic carbon metabolism, and response of dark uptake of 14CO2 with the addition of NH\\u000a 4\\u000a +\\u000a .

Alan W. Groeger

104

Nutrient limitation in Crater Lake, Oregon  

Microsoft Academic Search

Experiments were carried out to determine what nutrient (or nutrients) was primarily responsible for limiting phytoplankton\\u000a productivity in ultraoligotrophic Crater Lake. The experiments included in situ and laboratory nutrient addition bioassays\\u000a utilizing the natural phytoplankton community, Selenastrum capricornutum bottle assays, photosynthetic responses, photosynthetic carbon metabolism, and response of dark uptake of 14CO2 with the addition of NH\\u000a 4\\u000a +\\u000a .

Alan W. Groeger

2007-01-01

105

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.

2008-01-11

106

Nutrient-Specific Foraging in Invertebrate Predators  

NASA Astrophysics Data System (ADS)

Many herbivores and omnivores adjust their food selection behavior to regulate the intake of multiple nutrients. Carnivores, however, are generally assumed to optimize the rate of prey capture rather than select prey according to nutrient composition. We showed experimentally that invertebrate predators can forage selectively for protein and lipids to redress specific nutritional imbalances. This selection can take place at different stages of prey handling: The predator may select among foods of different nutritional composition, eat more of a prey if it is rich in nutrients that the predator is deficient in, or extract specific nutrients from a single prey item.

Mayntz, David; Raubenheimer, David; Salomon, Mor; Toft, Søren; Simpson, Stephen J.

2005-01-01

107

Nutrient conductivity effects on sweet pepper plants grown using a nutrient film technique  

Microsoft Academic Search

Sweet pepper (Capsicum annuum L.) plants were grown using Nutrient Film Technique (NFT) system with a nutrient solution of electrical conductivity (EC) 2 mS cm. Higher conductivity levels of 4, 6, 8, and 10 mS cm were achieved by adding concentrated KC1 solution to the basic nutrient solution. Higher ionic strength of the nutrient solution resulted in smaller sized fruit,

Teshome Tadesse; Michael A. Nichols; Keith J. Fisher

1999-01-01

108

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

Microsoft Academic Search

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

Ivan Valiela; Joseph E. Costa

1988-01-01

109

Nutrient spiralling in streams: implications for nutrient limitation and invertebrate activity  

Microsoft Academic Search

Nutrient cycling in streams occurs in conjunction with downstream transport as spatially distributed process that has been termed spiralling. The intensity of reutilization of nutrients as they pass downstream can be quantified in terms of the length of stream required for a nutrient atom to complete one (abstract) cycle; this distance is termed the spiralling length. The model for steady-state

J. D. Newbold; R. V. ONeill; J. W. Elwood; W. Van Winkle

1982-01-01

110

SSMILes: Measuring the Nutrient Tolerance of Algae.  

ERIC Educational Resources Information Center

Presents an activity integrating mathematics and science intended to introduce students to the use of metric measurement of mass as a way to increase the meaningfulness of observations about variables in life sciences. Involves measuring the nutrient tolerance of algae. Contains a reproducible algae nutrient graph. (Author/MKR)

Hedgepeth, David J.

1995-01-01

111

WASTEWATER TREATMENT WITH PLANTS IN NUTRIENT FILMS  

EPA Science Inventory

The nutrient film technique (NFT) is a unique modification of a hydroponic plant growth system which utilizes plants growing on an impermeable surface. A thin film of water flowing through the extensive root system provides nutrients for plants and associated microbial growth. Ro...

112

Acidic deposition, nutrient leaching and forest growth  

Microsoft Academic Search

Studies in Germany and confirmed in North America established that the forest decline that developed in the late 1970's and 80's resulted from a deficiency in one or more of the nutrient cations: Ca2+, Mg2+, and K+. These nutrients are essential to the structure of the foliage, to photosynthesis and to the growth of the trees. The reactions and mechanisms

George H. Tomlinson

2003-01-01

113

Processes and patterns of oceanic nutrient limitation  

NASA Astrophysics Data System (ADS)

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.

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

114

Docent Briefing NUTRIENTS...Why all the  

E-print Network

substantially reduced Phosphorus Nitrogen #12;Severe Algal Blooms Decreasing · Algal bloom frequency decreased frequency #12;Algal Bloom ­ Nutrient Relationships · Strong relationship between NITROGEN loads and algal to be a nutrient memory (~3 years) · Significant algal bloom reduction was achieved (~50%) Increasing Algal Blooms

Boynton, Walter R.

115

Pennsylvania Nutrient Management Specialist Certification Program  

E-print Network

v.06.2011 Pennsylvania Nutrient Management Specialist Certification Program Certification Trainings the PAPlants program (https://www.paplants.state.pa.us/). In order to use the PAPlants program, registrants must be enrolled in the Nutrient Management Certification Program administered by the Pennsylvania

Guiltinan, Mark

116

Pennsylvania Nutrient Management Specialist Certification Training Program  

E-print Network

v.09.2013 Pennsylvania Nutrient Management Specialist Certification Training Program Certification the PAPlants program (https://www.paplants.state.pa.us/). In order to use the PAPlants program, registrants must be enrolled in the Nutrient Management Certification Program administered by the Pennsylvania

Guiltinan, Mark

117

Nutrient movement in soils and its relation to ecosystem nutrient retention  

NASA Astrophysics Data System (ADS)

Nutrient limitation in terrestrial ecosystems is often accompanied with maintaining a nearly closed vegetation-soil nutrient cycle. The ability to retain nutrients in an ecosystem requires the capacity of the plant-soil system to draw down nutrient levels in soils effectually such that export concentrations in soil solutions remain low. We make use of a first principle model of nutrient diffusion and uptake at the root/micorrhizal surface to address how these soil processes shape levels of nutrient concentration in soil water and the magnitude of ecosystem nutrient export. We combine our analytical framework with available data on root properties and parameters for solute movements. Our results show that the physical environment permits plants to lower soil solute concentration substantially. Our analysis confirms that plant uptake capacities in soils are considerable such that water movement in soils is generally too small to significantly erode dissolved plant available nutrients. Our predicted levels of dissolved inorganic nitrogen concentrations are at the upper end of observed levels in soil water and headwater streams. Further efficient reduction of nutrient levels can be achieved through micorrhizal symbiosis, in particular if exudates reduce the buffering of ammonium, phosphate and other nutrients that tend to sorb to soil surfaces. As we scale our results from the environment of a single root to the entire active soil, we find that plant uptake capacity decreases as the intensity of soil water percolation increases, thereby weakening nutrient retention.

Gerber, S.; Brookshire, J.

2012-12-01

118

SUBMERGED MACROPHYTE EFFECTS ON NUTRIENT EXCHANGES IN RIVERINE SEDIMENTS  

EPA Science Inventory

Submersed macrophytes are important in nutrient cycling in marine and lacustrine systems, although their role in nutrient exchange in tidally-influenced riverine systems is not well studied. In the laboratory, plants significantly lowered porewater nutrient pools of riverine sedi...

119

Original article Biomass, litterfall and nutrient content in  

E-print Network

Original article Biomass, litterfall and nutrient content in Castanea sativa coppice stands November 1995) Summary - Aboveground biomass and nutrient content, litterfall and nutrient return) and Catania (Italy). Best regression equations for the aboveground biomass were obtained by applying the allo

Paris-Sud XI, Université de

120

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

SciTech Connect

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.

Radach, G. (Universitaet Hamburg (Germany))

1992-12-01

121

CSREES 406 National Integrated Water Quality Program-Nutrient Science Utilizing Mississippi River Diversions for Nutrient Management in  

E-print Network

;2 Utilizing Mississippi River Diversions for Nutrient Management in a Louisiana Coastal Watershed (NUMAN1 \\ CSREES 406 National Integrated Water Quality Program-Nutrient Science Utilizing Mississippi River Diversions for Nutrient Management in a Louisiana Coastal Watershed (NUMAN) PPROGRESS REPORT

122

Nutrient Criteria Technical Guidance Manual: Wetlands.  

National Technical Information Service (NTIS)

The purpose of this document is to provide scientifically defensible guidance to assist States, Authorized Tribes, Territories, and other authorized jurisdictions--hereafter referred to as States--in assessing the nutrient status of their wetlands, and to...

2007-01-01

123

Review article Disinfestation of recirculating nutrient solutions  

E-print Network

Review article Disinfestation of recirculating nutrient solutions in greenhouse horticulture David suppression, but few products are commercially available. recirculation / disinfestation / hydroponics The majority of greenhouse crops are grown using artificial substrates in hydroponic systems. These sub

Boyer, Edmond

124

MANGROVE-DERIVED NUTRIENTS AND CORAL REEFS  

EPA Science Inventory

Understanding the consequences of the declining global cover of mangroves due to anthropogenic disturbance necessitates consideration of how mangrove-derived nutrients contribute to threatened coral reef systems. We sampled potential sources of organic matter and a suite of sessi...

125

COMMONWEALTH OF PENNSYLVANIA NUTRIENT MANAGEMENT PROGRAM  

E-print Network

:_______________________________________________________________________ Date of Plan Approval:_______________________________ Operation Type (CAO, VAO or CAFO):_________________ Date of next 3 year Plan review:________________________ Program Compliance (* = Potential Act 38 Violations) 1. Nutrient Management Plan Implementation Yes No N/A a. Is the operation current with its

Guiltinan, Mark

126

Nutrient Addition Dramatically Accelerates Microbial Community Succession  

E-print Network

succession are widely debated, particularly for microorganisms. While successional soil microbial communities as an important control over soil microbial community development, greatly accelerating the rate of successionNutrient Addition Dramatically Accelerates Microbial Community Succession Joseph E. Knelman1

Colorado at Boulder, University of

127

Ocean chemistry: Fingerprints of a trace nutrient  

NASA Astrophysics Data System (ADS)

Lack of dissolved iron in the sea limits biological productivity and the uptake of carbon dioxide. The sources of dissolved iron in the North Atlantic Ocean have been identified from isotopic variations of this trace nutrient. See Letter p.212

Resing, Joseph A.; Barrett, Pamela M.

2014-07-01

128

Predator control of ecosystem nutrient dynamics.  

PubMed

Predators are predominantly valued for their ability to control prey, as indicators of high levels of biodiversity and as tourism attractions. This view, however, is incomplete because it does not acknowledge that predators may play a significant role in the delivery of critical life-support services such as ecosystem nutrient cycling. New research is beginning to show that predator effects on nutrient cycling are ubiquitous. These effects emerge from direct nutrient excretion, egestion or translocation within and across ecosystem boundaries after prey consumption, and from indirect effects mediated by predator interactions with prey. Depending on their behavioural ecology, predators can create heterogeneous or homogeneous nutrient distributions across natural landscapes. Because predator species are disproportionately vulnerable to elimination from ecosystems, we stand to lose much more from their disappearance than their simple charismatic attractiveness. PMID:20602626

Schmitz, Oswald J; Hawlena, Dror; Trussell, Geoffrey C

2010-10-01

129

Nutrient deficiencies after gastric bypass surgery.  

PubMed

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

Saltzman, Edward; Karl, J Philip

2013-01-01

130

HOW CHANGES IN NUTRIENT MANAGEMENT REGULATIONS  

E-print Network

typically have livestock (manure) USDA-NRCS Technical Standard 590 Impact of conservation planning Of Nutrients To Surface Water #12;The Water Erosion Process DETACHMENT Soil Sediment Load Sediment Transport

Balser, Teri C.

131

Growth, aboveground biomass, and nutrient concentration of young Scots pine and lodgepole pine in oil shale post-mining landscapes in Estonia.  

PubMed

The investigation was carried out in 8-year-old Scots pine (Pinus sylvestris L.) and lodgepole pine (Pinus contorta var. latifolia Engelm.) plantations on post-mining area, Northeast Estonia. The aim of the study was to assess the suitability of lodgepole pine for restoration of degraded lands by comparing the growth, biomass, and nutrient concentration of studied species. The height growth of trees was greater in the Scots pine stand, but the tree aboveground biomass was slightly larger in the lodgepole pine stand. The aboveground biomass allocation to the compartments did not differ significantly between species. The vertical distribution of compartments showed that 43.2% of the Scots pine needles were located in the middle layer of the crown, while 58.5% of the lodgepole pine needles were in the lowest layer of the crown. The largest share of the shoots and stem of both species was allocated to the lowest layer of the crown. For both species, the highest NPK concentrations were found in the needles and the lowest in the stems. On the basis of the present study results, it can be concluded that the early growth of Scots pine and lodgepole pine on oil shale post-mining landscapes is similar. PMID:21374054

Kuznetsova, Tatjana; Tilk, Mari; Pärn, Henn; Lukjanova, Aljona; Mandre, Malle

2011-12-01

132

Foods or Nutrients: Validity of Assessment Standards  

Microsoft Academic Search

LEARNING OUTCOME: To compare changes in dietary patterns based on food pyramid\\/CSFII groupings rather than Recommended Dietary AllowancesPeople select and consume foods not nutrients. Nutritionintervention appears to be most effective when clients are instructed about specific foods to eat and not eat. Yet when programs are evaluated for effectiveness, pre- and post-intervention intakes are compared based on specific nutrients in

PG Wolman; SF Stallings; CH Goodner

1996-01-01

133

Nutrient-Responsive Plant microRNAs  

Microsoft Academic Search

\\u000a Being sessile, plants have to cope with many adverse environmental changes, including changing nutrient availability. Adequate\\u000a availability of mineral macronutrients (e.g., N, P, K, S) and micronutrients (e.g., Cu, Fe, Zn) in the soil and their acquisition\\u000a are vitally important for plant growth, development, and reproduction. Too little or too much of the nutrients negatively\\u000a affects these traits and hence

Wolf-Rüdiger Scheible; Bikram Datt Pant; Magdalena Musialak-Lange; Przemyslaw Nuc

134

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

Microsoft Academic Search

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

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

1999-01-01

135

Nutrient fluxes from water to land: seabirds affect plant nutrient status on Gulf of California islands  

Microsoft Academic Search

Energy and nutrient fluxes across habitat boundaries can exert profound direct and indirect effects on the dynamics of recipient\\u000a systems. Transport from land to water is common and well studied; here, we document a less recognized process, substantial\\u000a flows from water to land. On hyperarid, naturally nutrient poor islands in the Gulf of California, nutrient input via seabird\\u000a guano directly

Wendy B. Anderson; Gary A. Polis

1999-01-01

136

Nutrient Shielding in Clusters of Cells  

PubMed Central

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 between 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 ?. PMID:23848711

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

2014-01-01

137

Nutrient shielding in clusters of cells  

NASA Astrophysics Data System (ADS)

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 ?.

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

2013-06-01

138

Improving nutrient efficiency as a strategy to reduce nutrient surpluses on dairy farms.  

PubMed

Dutch nutrient policy aims at reducing leaching of agricultural nutrients by internalizing the negative externalities associated with inefficient nutrient use. This is done by taxation of nitrogen and phosphate surpluses that exceed a hectare-based threshold of maximum-allowed surpluses. One management strategy farmers may use to reduce the nutrient surpluses on their farms is to improve the nutrient efficiency of the agricultural production process. This study employs Data Envelopment Analysis (DEA) to calculate nitrogen and phosphate efficiencies and an overall nutrient efficiency measure for a 3-year panel of 114 Dutch dairy farms. Subsequent analyses show the impact of both farm intensity and nutrient efficiency on the nitrogen and phosphate surpluses. It appears that farm intensity has a positive effect on efficiency, but efficiency and intensity exert opposite influences on nutrient surpluses. This is especially the case for nitrogen. The magnitude of a possible reduction of nitrogen surpluses through a strategy of efficiency improvement is therefore limited by the intensity of the farming system, unless the technology with which nutrients are used by the farming system can be further improved or input/output ratios will be altered. PMID:12805888

Ondersteijn, C J; Lansink, A G; Giesen, G W; Huirne, R B

2001-10-24

139

Calibration models for electromagnetic induction methods to assess nutrient accumulation beneath confined livestock areas.  

PubMed

Nutrient accumulation in soils beneath confined livestock areas is a potential source of groundwater contamination. Electromagnetic induction (EMI) has become a practical method to assess nutrient content, with multiple linear regression (MLR) as the statistical method often employed to translate EMI readings into nutrient content. The purpose of this research is to compare and contrast the performance of spatially referenced MLR models that include secondary, 'easy-to-acquire' predictor variables such as spatial coordinate locations, soil water content and elevation information with MLR models based solely on EMI readings. Six feedlot areas were surveyed with an EM38 conductivity meter and between 6 and 12 sites at each feedlot were sampled at five different depths. The electrical conductivity (EC(e)), nitrate (NO3-) and phosphate (PO4(3-)) concentrations were measured and used as response variables. Analyses were performed using two different approaches: the response variables in individual layers and response variables by combining the layers within the soil profile. The results of both MLR methods were comparable in most instances because the models preferentially incorporated predictors derived from EM38 readings. Differences between the models were more evident when predicting NO3- and PO4(3-), even though prediction of these two analytes by either method was generally poor. Combined profile analysis was more effective for defining nutrient build-up because by-layer analysis gave non-significant or poor models in many instances. PMID:21473273

Cordeiro, Marcos R C; Ranjan, R Sri; Ferguson, Ian J

2011-01-01

140

A Comparison of Nutrient Density Scores for 100% Fruit Juices  

Microsoft Academic Search

The 2005 Dietary Guidelines for Americans recommend that consumers choose a variety of nutrient- dense foods. Nutrient density is usually defined as the quantity of nutrients per calorie. Food and nutrition profes- sionals should be aware of the concept of nutrient density, how it might be quantified, and its potential application in food labeling and dietary guidance. This article presents

G. C. Rampersaud

2007-01-01

141

Adapting a CAFO's NMP for Today's Nutrient Challenges  

Microsoft Academic Search

Are nutrient planning processes adapting to our changing knowledge of nutrient issues on animal feeding operations? Our current public policy focuses nutrient planning procedures on efficient recycling of manure nutrients within the boundaries of an animal feeding operation's property. While this approach is an important step towards achieving sustainable animal feeding operations, it may not be the final solution for

Rick Koelsch

142

Food web interactions and nutrients dynamics in polyculture ponds  

Microsoft Academic Search

Artificial feed and fertilizers are the main sources of nutrients supporting fish growth in aquaculture ponds. The majority of the added nutrients are lost to the sediment, where they are no longer available for natural food production. By increasing resuspension of the sediment through the introduction of benthivorous fish, nutrient loss may be reduced, because of the re-mobilisation of nutrients

M. M. Rahman

2006-01-01

143

Nutrient Management Educational & Planning Resources The Pennsylvania Nutrient Management Education Program provides a wide array of resources  

E-print Network

v.08.2011 Nutrient Management Educational & Planning Resources The Pennsylvania Nutrient Management Education Program provides a wide array of resources to nutrient management specialists the material presented in the certification trainings and to cover aspects of nutrient management and related

Guiltinan, Mark

144

Marine nutrient contributions to tidal creeks in Virginia: spawning marine fish as nutrient vectors to freshwater ecosystems  

Microsoft Academic Search

Coastal freshwater streams are typically viewed as conduits for the transport of sediment and nutrients to the coasts. Some coastal streams however experience seasonal migrations of anadromous fish returning to the freshwater to spawn. The fish may be vectors for the delivery of marine nutrients to nutrient poor freshwater in the form of excreted waste and post-spawning carcasses. Nutrients derived

S. E. Macavoy; G. C. Garman

2006-01-01

145

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

ERIC Educational Resources Information Center

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…

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

146

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...

147

NutrientManagementaself-studycoursefromtheMSUExtensionServiceContinuingEducationSeries Nutrient Management Module No. 9  

E-print Network

and growth. A plant's sufficiency range is defined as the range of nutrient necessary to meet the plant's nutritional needs and maximize growth (Figure 1). The width of this range will depend upon individual plant of a growing plant. Toxicity occurs when a nutrient is in excess of plant needs and decreases plant growth

Lawrence, Rick L.

148

YAQUINA BAY NUTRIENT CRITERIA CASE STUDY: APPROACHES TO ESTUARINE NUTRIENT CRITERIA IN THE PACIFIC NORTHWEST  

EPA Science Inventory

The presentation presents an introduction to the Yaquina Bay Nutrient Case Study which provides approaches for development of estuarine nutrient criteria in the Pacific Northwest. As part of this effort, a database of historic and recent data has been assembled consisting of phy...

149

YAQUINA ESTUARY NUTRIENT CRITERIA CASE STUDY: GUIDANCE FOR DEVELOPING NUTRIENT CRITERIA IN THE PACIFIC NORTHWEST  

EPA Science Inventory

The presentation provides an introduction to the Yaquina Estuary Nutrient Case Study which includes considerations for development of estuarine nutrient criteria in the Pacific Northwest. As part of this effort, a database of historic and recent data has been assembled consistin...

150

Nutrient transporters: the Achilles' heel of anabolism  

PubMed Central

Highly proliferative cells, including cancer cells, require a constant supply of molecular building blocks to support their growth. To acquire substrates such as glucose and amino acids from the extracellular space, dividing cells rely on transporter proteins in the plasma membrane. Numerous studies link transcriptional and post-translational control of nutrient transporter expression with proliferation, highlighting the importance of nutrient transporters in both physiologic and pathologic growth. Here we review recent work that spotlights the crucial role of nutrient transporters in cell growth and proliferation, discuss post-translational mechanisms for coordinating expression of different transporters, and consider the therapeutic potential of targeting these proteins in cancer and other diseases characterized by inappropriate cell division. PMID:23402769

McCracken, Alison N.; Edinger, Aimee L.

2013-01-01

151

Quantitative evolutionary design of nutrient processing: Glucose  

PubMed Central

Quantitative evolutionary design involves the numerical relationships, evolved through natural selection, of biological capacities to each other and to natural loads. Here we study the relation of nutrient-processing capacities of the intestine and of organs beyond it (such as liver and kidneys) to each other and to natural loads of nutrients normally consumed. To control experimentally the rate of nutrient delivery to organs beyond the intestine, we administered nutrients directly into the veins of rats by the method of total parenteral nutrition (TPN). Control rats consuming the TPN solution by mouth ingested glucose at 42 mmol/day and processed it completely, as gauged by negligible appearance of glucose in urine and feces. Experimental rats receiving TPN were able to process infused glucose completely at rates up to 92 mmol/day. At higher infusion rates, they were unable to process further glucose, as gauged by rises in serum and urinary glucose levels and serum osmolality. At the highest infusion rates, they exhibited diuresis, dehydration, and both decreased weight gain and survival. These symptoms closely resemble the human diabetic condition known as nonketotic hypertonicity. Thus, a rat's body has a safety factor of 2.2 (=92/42) for glucose processing: it can process glucose at a rate 2.2 times its voluntary intake. This safety factor represents apparent excess capacity that may have evolved to process other nutrients converted into glucose, to minimize the risk of loads swamping capacities, to handle suddenly increased nutrient requirements, or to effect rapid mobilization of glucose. PMID:12077313

Steyermark, Anthony C.; Lam, Mandy M.; Diamond, Jared

2002-01-01

152

Export of nutrients from the Arctic Ocean  

NASA Astrophysics Data System (ADS)

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.

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

153

Mapping Nutrients Crucial to a Growing Population  

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

154

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)

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.

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

2013-04-01

155

Review of Nutrient Management in Freshwater Polyculture  

Microsoft Academic Search

One of the most important issues concerning fish-pond fertilization is the determination of the optimal amount of fertilizer to be applied to the pond system. Another important concern is the suitability of fish species for polyculture in order to optimize production. The dynamics of nutrients, phytoplankton, and fish is a complex subject and practitioners are often compelled to formulate solutions

Martin S. Kumar; Samantha N. Burgess; Le Thanh Luu

2005-01-01

156

Scouting and Managing Greenhouse Nutrient Problems  

E-print Network

-logged or poorly drained media. Conducting regular testing of media pH and EC is vital. pH affects the availability, or water-management problems rather than fertilizer type or concentration. Checking the roots is important of nutrients and EC gives you the overall concentration of fertilizer salts in the media. For plugs, test 2

New Hampshire, University of

157

Estimation of Nutrient Requirements from Growth Data  

Microsoft Academic Search

Two least squares methods of estimating nutrient require ments from growth data were compared. One method involved fitting a broken line by the method of least squares. The requirement was taken as the abscissa of the breakpoint in the curve. The other method involved fitting an appropriate exponential function to the growth data and estimat ing the requirement as the

KELLY R. ROBBINS; HORACE W. NORTON; ANDDAVID H. BAKER

158

4, 32293265, 2007 Carbon and nutrient  

E-print Network

Research, Geesthacht, Germany * now at: Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL1 to investigate nutrient and carbon processes within the Norwegian Sea. Nitrate is consumed by phytoplankton and sequestration of CO2, primary production and large-scale ocean mixing. As with many other high latitude

Paris-Sud XI, Université de

159

ANIMAL MANURES AS FEEDSTUFFS: NUTRIENT CHARACTERISTICS  

EPA Science Inventory

This study critically evaluates the potential value of animal manure as feedstuffs for livestock and poultry using information in the published literature. The paper provides an assessment of the nutrient and economic value of manures as a function of their composition when compa...

160

Effects of Nutrients on Spring Ecosystems  

Microsoft Academic Search

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,

Robert L. Knight; Sky K. Notestein

161

EFFECT OF NUTRIENT INTAKE ON PREMENSTRUAL DEPRESSION  

E-print Network

. depression, anxiety. mood swings, cravings for carbohydrate-rich foods, sleep dis- turbances, and somatic craving. Calorie and nutrient intakes were measured directly. The subjects with premenstrual syndrome failed to change, whereas intake of fat, a fixed constituent of all of the test foods, rose in proportion

Wurtman, Richard

162

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...

163

The Effects of Amniotic Nutrient Administration, \\  

Microsoft Academic Search

3 Abstract: In ovo feeding (IOF), injecting nutrients into the amnion, may improve growth performance by enhancing circulating IGF's and glycogen reserves. To test this hypothesis 400 Hybrid® turkey eggs were injected into the amnion with 1.5 ml saline solutions consisting of 4 IOF formulation treatments consisting of a factorial arrangement of 2 levels of arginine (ARG 0 or 0.7%)

2006-01-01

164

Can nutrient loads predict marine water quality?  

NSDL National Science Digital Library

This American Chemical Society article explores whether phosphorous or nitrogen plays a larger role in creating the algal blooms of the Mississippi River dead zone. It documents results of a study that finds that the algae-nutrient interaction is complex, but that the system is more phosphorous limited upstream and becomes more nitrogen limited farther downstream.

Pelley, Janet; Society, American C.

165

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

166

Nutrient farming: The business of environmental management  

Microsoft Academic Search

Restored wetlands could be used successfully to address our recurring problems of excess nutrients (and sediments) and flood damages along U.S. rivers. Credit markets for flood storage, nitrogen, phosphorous, carbon, atrazine, sediment, and many other constituents would economically motivate landowners to restore wetlands. The resulting high-quality open space would provide for recreation, wildlife habitat, and biodiversity. By instigating the market

Donald L. Hey; Laura S. Urban; Jill A. Kostel

2005-01-01

167

Nutrient Management Module No. 10 Fertilizers and  

E-print Network

Nutrient Management Module No. 10 Commercial Fertilizers and Soil Amendments by Ann McCauley, Soil fertilizer reactions in the soil 5. Determine the appropriate soil amendment for a given soil condition 6Managementaself-studycoursefromMSUExtensionContinuingEducationSeries 4449-10 May 2009 10 #12;Module 10: Commercial Fertilizers and Soil Amendments2 Background Commercial

Lawrence, Rick L.

168

River Nutrient Loads and Catchment Size  

Microsoft Academic Search

We have used a total of 496 sample sites to calibrate a simple regression model for calculating dissolved inorganic nutrient fluxes via runoff to the ocean. The regression uses the logarithms of runoff and human population as the independent variables and estimates the logarithms of dissolved inorganic nitrogen and phosphorus loading with R2 values near 0.8. This predictive capability is

S. V. Smith; D. P. Swaney; R. W. Buddemeier; M. R. Scarsbrook; M. A. Weatherhead; C. Humborg; H. Eriksson; F. Hannerz

2005-01-01

169

21 CFR 107.10 - Nutrient information.  

Code of Federal Regulations, 2010 CFR

...cholecalciferol, vitamin E content in units of milligram...potassium, and chloride content in units of...choline, and inositol content shall be declared except...listed nutrients, and the caloric density, may also...identified as essential by the Food and Drug...

2010-04-01

170

Uncertainty Propagation in an Ecosystem Nutrient Budget.  

EPA Science Inventory

New aspects and advancements in classical uncertainty propagation methods were used to develop a nutrient budget with associated error for a northern Gulf of Mexico coastal embayment. Uncertainty was calculated for budget terms by propagating the standard error and degrees of fr...

171

Estimating reference nutrient criteria for Maryland ecoregions.  

PubMed

Management of stream nutrients is becoming increasingly important in order to protect both water quality and aquatic resources throughout the USA. Using an extensive water quality database from the long-term Maryland Biological Stream Survey (MBSS), we describe nutrient relationships to landscape characteristics as total nitrogen (TN) and total phosphorus (TP) of small-order, non-tidal streams in USEPA L2 and L3 ecoregions in Maryland and by MBSS stream order at the L2 and L3 ecoregion levels. To protect stream ecosystem integrity, preliminary reference nutrient estimates (TN and TP) as percentiles (25th of all stream reaches and 75th of stream reference reaches) for the six Maryland L3 ecoregions are: Blue Ridge TN 0.29 and 0.64 mg/L, TP 0.0065 and 0.0090 mg/L; Central Appalachians TN 0.40 and 1.0 mg/L, TP 0.0060 and 0.015 mg/L; Middle Atlantic Coastal Plains TN 0.93 and 2.5 mg/L, TP 0.094 and 0.065 mg/L; Northern Piedmont TN 1.6 and 1.8 mg/L, TP 0.010 and 0.015 mg/L; Ridge and Valley TN 0.40 and 0.98 mg/L, TP 0.0063 and 0.012 mg/L; and Southeastern Plains TN 0.33 and 0.82 mg/L, TP 0.016 and 0.042 mg/L. High levels of both TN and TP are present in many streams found in non-tidal watersheds associated with all Maryland ecoregions, but are especially elevated in the Northern Piedmont and Middle Atlantic Coastal Plain ecoregions, with the latter second-order streams (average TN?>?2.9 mg/L) significantly higher than all other ecoregion-order combinations. Across all six ecoregions, mean nutrient loading for both TN and TP was generally equivalent in first-order streams to nutrient concentrations seen in both second- and third-order streams, indicating a definite need to increase efforts in preventing nutrients from entering first-order streams. Small-order stream nutrient levels are the drivers for subsequent TN and TP inputs into the upper freshwater tidal reaches of the Chesapeake Bay, resulting in a potential risk for altered estuarine ecosystems. PMID:22644126

Morgan, Raymond P; Kline, Kathleen M; Churchill, John B

2013-03-01

172

Nutrient-substituted hydroxyapatites: synthesis and characterization  

NASA Technical Reports Server (NTRS)

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.

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

1999-01-01

173

Nutrient Status of Adults with Cystic Fibrosis  

PubMed Central

Nutrition is thought to influence disease status in patients with cystic fibrosis (CF). This cross-sectional study sought to evaluate nutrient intake and anthropometric data from 64 adult outpatients with cystic fibrosis. Nutrient intake from food and supplements was compared with the Dietary Reference Intakes for 16 nutrients and outcomes influenced by nutritional status. Attention was given to vitamin D and calcium given potential skeletal implications due to cystic fibrosis. Measurements included weight, height, body composition, pulmonary function, and serum metabolic parameters. Participants were interviewed about dietary intake, supplement use, pulmonary function, sunlight exposure, and pain. The participants’ mean body mass index (±standard deviation) was 21.8±4.9 and pulmonary function tests were normal. Seventy-eight percent used pancreatic enzyme replacement for malabsorption. Vitamin D deficiency [25-hydroxyvitamin D (25OHD)<37.5 nmol/L] was common: 25 (39%) were deficient despite adequate vitamin D intake. Lipid profiles were normal in the majority, even though total and saturated fat consumption represented 33.0% and 16.8% of energy intake, respectively. Reported protein intake represented 16.9% of total energy intake (range 10%–25%). For several nutrients, including vitamin D and calcium, intake from food and supplements in many participants exceeded recommended Tolerable Upper Intake Levels. Among adults with cystic fibrosis, vitamin D deficiency was common despite reported adequate intake, and lipid profiles were normal despite a relatively high fat intake. Mean protein consumption was adequate, but the range of intake was concerning, as both inadequate or excessive intake may have deleterious skeletal effects. These findings call into question the applicability of established nutrient thresholds for patients with cystic fibrosis. PMID:18060897

GORDON, CATHERINE M.; ANDERSON, ELLEN J.; HERLYN, KAREN; HUBBARD, JANE L.; PIZZO, ANGELA; GELBARD, RONDI; LAPEY, ALLEN; MERKEL, PETER A.

2011-01-01

174

Nutrient and nonnutrient renal blood flow  

SciTech Connect

The role of prostaglandins in the distribution of total renal blood flow (TRBF) between nutrient and nonnutrient compartments was investigated in anesthetized mongrel dogs. Renal blood flow distribution was assessed by the xenon 133 freeze-dissection technique and by rubidium 86 extraction after ibuprofen treatment. Ibuprofen (13 mg/kg) significantly decreased TRBF by 16.3% +/- 1.2% (mean +/- SEM electromagnetic flow probe; p less than 0.005), but did not alter blood flows to the outer cortex (3.7 vs 4.3 ml/min per gram), the inner cortex (2.6 vs 2.7 ml/min per gram), and the other medulla (1.5 vs 1.5 ml/min per gram), which suggests a decrease in nonnutrient flow. In a separate group of animals the effect of reduced blood flow on the nutrient and nonnutrient components was determined by mechanically reducing renal arterial blood flow by 48%. Unlike the ibuprofen group, nutrient blood flows were proportionally reduced with the mechanical decrease in TRBF in the outer cortex (1.9 ml/min per gram, p less than 0.05), the inner cortex (1.4 ml/min per gram, p less than 0.05), and the outer medulla (0.8 ml/min per gram, p less than 0.01). These results indicate no shift between nutrient and nonnutrient compartments. Nutrient and nonnutrient renal blood flows of the left kidney were also determined by 86Rb extraction. After ibuprofen treatment, nonextracted 86Rb decreased to 12.1% from the control value of 15.6% (p less than 0.05). Mechanical reduction of TRBF did not significantly decrease the proportion of unextracted 86Rb (18.7%).

Young, J.S.; Passmore, J.C.; Hartupee, D.A.; Baker, C.H. (Univ. of Louisville, KY (USA))

1990-06-01

175

Seasonal Asynchrony in Terrestrial Nutrient Production and Demand Drives Nutrient Delivery to Arctic Streams  

NASA Astrophysics Data System (ADS)

Plant species that currently dominate the terrestrial plant community in the Arctic become dormant and cease to require nutrients shortly after the peak in the growing season in late-July to early August. However, deeper soils in the active layer may not freeze until much later, in mid-October to mid-November. Thus, there is a period of time in which vegetation demand for nutrients is low but soils are sufficiently warm to maintain microbial activity and to allow continued runoff from land to streams. Previously we hypothesized that this "seasonal asynchrony" in nutrient dynamics should lead to increased nutrient loading to streams in the fall. We used a small watershed close to the Toolik Lake Field Station on the North Slope of Alaska to test this hypothesis. We collected phenological observations to assess plant senescence, spectral irradiance data to calculate vegetation "greenness" (NDVI), and samples of stream water for nutrient analyses from mid-July through early October 2011. We found, as hypothesized, that the concentration and flux of nitrate increased significantly in this test watershed coincident with declines in NDVI that occur as plants senesced (Figure). Increases in other important nutrients (phosphate and ammonium) were not significant. We confirmed that this was a general phenomenon and not a unique characteristic of the test watershed by sampling nutrients in five other watersheds in the area ranging from tundra to mountain terrain. All watersheds exhibited the same general behavior of elevated nitrate during the transition from the growing season to the early winter season. We conclude that this is a general phenomenon that we have not observed previously because our long-term water research and monitoring programs have, until recently, been restricted to the core summer season. Increased nutrient loading due to seasonal asynchrony in nutrient dynamics is unlikely to be a new phenomenon. However, we expect the duration of this seasonal asynchrony - the period between plant dormancy and complete freeze up of soils - to increase as the Arctic region continues to warm. The effects of greater nutrient loading to arctic streams late in the season are unknown but include alteration of local stream ecosystem dynamics and/or increased delivery of nutrients to oligotrophic coastal and marine ecosystems.

Bowden, W. B.; Khosh, M. S.; Waldvogel, G.; Gooseff, M. N.; Wollheim, W. M.; Whittinghill, K. A.; Wlostowski, A. N.; Jacobson, A. D.; McClelland, J. W.; Douglas, T. A.; Lehn, G. O.; Barker, A.

2012-12-01

176

Degrading uplands in the rainforest region of Madagascar: Fallow biomass, nutrient stocks, and soil nutrient availability  

Microsoft Academic Search

Soil fertility restoration depends on natural fallows in the slash-and-burn system of eastern Madagascar. In the Beforona-Vohidrazana\\u000a study zone, none of the fallow species are able to withstand the slashing, burning and cropping frequencies of 3–5 years.\\u000a Eventually soils are abandoned for agriculture. Along the degradation sequence, this study quantifies fallow biomass, nutrient\\u000a stocks and soil nutrient availability of four dominant

Erika Styger; Erick C. M. Fernandes; Harivelo M. Rakotondramasy; Eric Rajaobelinirina

2009-01-01

177

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 ...

178

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...

179

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...

180

Nutrient release, recovery and removal from waste sludge of a biological nutrient removal system.  

PubMed

The uncontrolled release of nutrients from waste sludge results in nitrogen and phosphorus overloading in wastewater treatment plants when supernatant is returned to the inlet. A controlled release, recovery and removal of nutrient from the waste sludge of a Biological Nutrient Removal system (BNR) are investigated. Results showed that the supernatant was of high mineral salt, high electrical conductivity and poor biodegradability, in addition to high nitrogen and phosphorus concentrations after the waste sludge was hydrolysed through sodium dodecyl sulphate addition. Subsequently, over 91.8% of phosphorus and 10.5% of nitrogen in the supernatants were extracted by the crystallization method under the conditions of 9.5 pH and 400 rpm. The precipitate was mainly struvite according to X-ray diffraction and morphological examination. A multistage anoxic-oxic Moving Bed Biofilm Reactor (MBBR) was then adopted to remove the residual carbon, nitrogen and phosphorus in the supernatant. The MBBR exhibited good performance in simultaneously removing carbon, nitrogen and phosphorus under a short aeration time, which accounted for 31.25% of a cycle. Fluorescence in situ hybridization analysis demonstrated that nitrifiers presented mainly in floc, although higher extracellular polymeric substance content, especially DNA, appeared in the biofilm. Thus, a combination of hydrolysis and precipitation, followed by the MBBR, can complete the nutrient release from the waste sludge of a BNR system, recovers nutrients from the hydrolysed liquor and removes nutrients from leftovers effectively. PMID:25176308

Wang, Yi; Zheng, Shu-Jian; Pei, Li-Ying; Ke, Li; Peng, Dang-Cong; Xia, Si-Qing

2014-01-01

181

CH4 emissions from two floodplain fens of differing nutrient status  

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

182

Assessment of Nutrient Stability in Space Foods  

NASA Technical Reports Server (NTRS)

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.

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

2009-01-01

183

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

ERIC Educational Resources Information Center

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…

Brothers, Chris; And Others

184

REGULAR ARTICLE Tree mixture effects on aboveground nutrient pools  

E-print Network

REGULAR ARTICLE Tree mixture effects on aboveground nutrient pools of trees in an experimental biomass in mixtures than in monocultures while Cedrela odorata ­ the most nutrient efficient species ­ produced more biomass independent of stem growth rates because they acquired more nutrients in mixtures

Potvin, Catherine

185

The European Nutrient Database (ENDB) for Nutritional Epidemiology  

Microsoft Academic Search

Food composition databases (FCDB), as well as standardized calculation procedures are required for international studies on nutrition and disease to calculate nutrient intakes across countries. Comparisons of national FCDBs have shown that major improvements are needed in standardization and documentation at the food and nutrient levels to minimize systematic and random errors in nutrient intake estimations. The International Agency for

U. R. Charrondiere; J. Vignat; A. Møller; J. Ireland; W. Becker; S. Church; A. Farran; J. Holden; C. Klemm; A. Linardou; D. Mueller; S. Salvini; L. Serra-Majem; G. Skeie; W. van Staveren; I. Unwin; S. Westenbrink; N. Slimani; E. Ribol

2002-01-01

186

Artificial Soil With Build-In Plant Nutrients  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

187

Nutrient export from freshwater ecosystems by anadromous sockeye salmon (Oncorhynchus  

E-print Network

Nutrient export from freshwater ecosystems by anadromous sockeye salmon (Oncorhynchus nerka to freshwater ecosystems at low spawning densities. Ig- noring nutrient export by outgoing smolts will consistently lead to overestimation of nutrient import by Pacific salmon to freshwater ecosystems. Résumé : Les

188

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...

189

Nutrient proportions in foliage of semi-mature loblolly pine  

Microsoft Academic Search

Summary Nitrogen and phosphorus limitations to growth are common in many loblolly pine (Pinus taeda) stands. Interactions of these nutrients may complicate interpretation of foliar nutrient analysis for predicting response to forest fertilization. Proportions of foliar nutrient concentrations (and the changes in these proportions following fertilization) were examined in 36 semi-mature loblolly pine plantations in the southeastern United States. Mean

M. B. Adams; H. L. Allen

1985-01-01

190

Original article Biomass and nutrient cycling of a highly productive  

E-print Network

Original article Biomass and nutrient cycling of a highly productive Corsican pine stand on former 14 April; accepted 22 September 1997) Abstract - Biomass and nutrient cycling were examined in a 62 on a coarse and dry sandy soil with low exchangeable nutrient pools. Total aboveground biomass was estimated

Paris-Sud XI, Université de

191

Nutrient Management Certification for Delaware: Developing a Water Quality Curriculum  

ERIC Educational Resources Information Center

Water quality is a critical environmental, social, and political issue in Delaware. In the late 1990s, a series of events related to water quality issues led to the passage of a state nutrient management law. This new law required nutrient management planning and established a state certification program for nutrient users in the agricultural and…

Hansen, David J.; Binford, Gregory D.

2004-01-01

192

Droop models of nutrient-plankton interaction with intratrophic predation  

E-print Network

Droop models of nutrient-plankton interaction with intratrophic predation S. R.-J. Jang1 , J are positive, plankton populations can become extinct if the input nutrient concentration is modeled randomly and interpret nutrient-plankton interactions very successfully. Intratrophic predation on the other hand has

Baglama, James

193

A Nutrient Density-Nutrition Education Program for Elementary Schools.  

ERIC Educational Resources Information Center

Presents a nutrient density-nutrition education program that was developed and evaluated for students K-6. The program is designed to be integrated into existing curricula. Nutrient density, which compares the nutrients in food with its caloric content, serves as the conceptual framework of the program. (Author/MA)

Brown, Guendoline; And Others

1979-01-01

194

Nutrient Input into the Caspian Sea with River Runoff  

Microsoft Academic Search

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

A. V. Leonov; N. A. Nazarov

2001-01-01

195

Nutrient Management Specialist or Broker Signature The following appendices need to accompany the Nutrient Balance Worksheets if applicable  

E-print Network

the Nutrient Balance Worksheets if applicable: · Maps of fields where manure is to applied including manure Nutrient Balance Worksheet Appendices Date of Development February 6, 2009 NBS Cover Page - Page 1 Version

Guiltinan, Mark

196

Linkages Between Nutrients and Assemblages of Macroinvertebrates and Fish in Wadeable Streams: Implication to Nutrient Criteria Development  

Microsoft Academic Search

We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates\\u000a and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships\\u000a between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient\\u000a criteria development; and (3) evaluate the importance of

Lizhu Wang; Dale M. Robertson; Paul J. Garrison

2007-01-01

197

Nutrient Cycles and Pollution, Lake Michigan Style  

NSDL National Science Digital Library

This “clicker case” introduces students to the basics of nutrient cycling using a recent example of the expansion of a refinery on Lake Michigan. The story is told through a series of news clips from Chicago’s National Public Radio affiliate, WBEZ, which covers the northeastern Illinois and northwestern Indiana region.  The case is presented in class using a series of PowerPoint slides (~3.7MB) punctuated by questions that the students answer using electronic personal response systems, or "clickers." The case was designed for use in an upper-level introductory ecology course. It would be equally well suited in lower-level ecology courses as well as environmental science courses, and in an introductory biology course that covers nutrient cycles and/or pollution.

Heinz, Cheryl A.

2010-01-01

198

Porous membrane utilization in plant nutrient delivery  

NASA Technical Reports Server (NTRS)

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.

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

1987-01-01

199

Plants integrate information about nutrients and neighbors.  

PubMed

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

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

2010-06-25

200

Enhanced plant nutrient use efficiency with PGPR and AMF in an integrated nutrient management system.  

PubMed

A 3 year field study was conducted with field corn from 2005 to 2007 to test the hypothesis that microbial inoculants that increase plant growth and yield can enhance nutrient uptake, and thereby remove more nutrients, especially N, P, and K from the field as part of an integrated nutrient management system. The field trial evaluated microbial inoculants, which include a commercially available plant growth-promoting rhizobacteria (PGPR), arbuscular mycorrhiza fungi (AMF), and their combination across 2 tillage systems (no-till and conventional till) and 2 fertilization regimes (poultry litter and ammonium nitrate). Data were collected on plant height, yield (dry mass of ears and silage), and nutrient content of corn grain and silage. In addition, nutrient content of soil was determined, and bioavailability of soil nutrient was measured with plant root simulator probes. Results showed that inoculants promoted plant growth and yield. For example, grain yields (kg.ha(-1)) in 2007 for inoculants were 7717 for AMF, 7260 for PGPR+AMF, 7313 for PGPR, 5725 for the control group, and for fertilizer were 7470 for poultry litter and 6537 for NH4NO3. Nitrogen content per gram of grain tissues was significantly enhanced in 2006 by inoculant, fertilizer, and their interactions. Significantly higher amounts of N, P, and K were removed from the plots with inoculants, based on total nutrient content of grain per plot. These results supported the overall hypothesis and indicate that application of inoculants can lead to reduction in the build up of N, P, and K in agricultural soils. Further studies should be conducted to combine microbial inoculants with reduced rates of fertilizer. PMID:18923557

Adesemoye, A O; Torbert, H A; Kloepper, J W

2008-10-01

201

Nutrient Management in Conservation Tillage Systems  

E-print Network

Extension Number Four C O N S E R V A T I O N T I L L A G E S E R I E S o understand soil fertility will affect plants' rooting patterns, usually resulting in higher concentrations of roots near the soil to find mois- ture and nutrients. Soil pH often is stratified in conservation tillage systems because

Kaye, Jason P.

202

Lichen Substances Prevent Lichens from Nutrient Deficiency  

Microsoft Academic Search

The dibenzofuran usnic acid, a widespread cortical secondary metabolite produced by lichen-forming fungi, was shown to promote\\u000a the intracellular uptake of Cu2+ in two epiphytic lichens, Evernia mesomorpha and Ramalina menziesii, from acidic, nutrient-poor bark. Higher Cu2+ uptake in the former, which produces the depside divaricatic acid in addition to usnic acid, suggests that this depside promotes\\u000a Cu2+ uptake. Since

Markus Hauck; Karen Willenbruch; Christoph Leuschner

2009-01-01

203

Chasing Nutrients with an Arctic Sedge  

NASA Astrophysics Data System (ADS)

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.

Iverson, S. L.; Schimel, J.

2013-12-01

204

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

Microsoft Academic Search

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

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

2004-01-01

205

Mineral Nutrient Requirements of Cucumber Seedlings 1  

PubMed Central

Mineral nutrient requirements for maximum growth rate of cucumber (Cucumis sativus L.) seedlings are estimated on the basis of three criteria. 1. The optimal weight proportions among the nutrients present in the seedlings. In relation to N = 100, close to 75 K, 13 P, 9 Ca, and 9 Mg are required. 2. The optimal ratio between the nitrogen sources NH4 and NO3 in the solution. The best growth is recorded with about equivalent amounts. Nitrate alone is also highly productive. Cucumber prefers nitrate and is sensitive to high ammonium concentrations. 3. The optimal total concentration in the solution corresponds to 200 to 300 milligrams of nitrogen per liter, with the proportions of the nutrients according to criterion 1. Simple growth methods are suggested in which the three criteria are fulfilled. Calcium, especially, is found to accumulate in older leaves. It is proposed that this is not an expression for a physiological requirement for calcium but a mechanism for deposition of excess uptake important in adaptation to calcareous soils. This mechanism also operates at low calcium uptake rates, causing deficiency in the young parts, despite relatively high contents in the old leaves. Cucumber is therefore interpreted to be an obligate calcicole. The results are discussed in relation to similar experiments with birch (Betula verrucosa Ehrh.) seedlings, a species able to grow on very acid soils. PMID:16658558

Ingestad, Torsten

1973-01-01

206

Invasive aquarium fish transform ecosystem nutrient dynamics  

PubMed Central

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

Capps, Krista A.; Flecker, Alexander S.

2013-01-01

207

Nutrient addition dramatically accelerates microbial community succession.  

PubMed

The ecological mechanisms driving community succession are widely debated, particularly for microorganisms. While successional soil microbial communities are known to undergo predictable changes in structure concomitant with shifts in a variety of edaphic properties, the causal mechanisms underlying these patterns are poorly understood. Thus, to specifically isolate how nutrients--important drivers of plant succession--affect soil microbial succession, we established a full factorial nitrogen (N) and phosphorus (P) fertilization plot experiment in recently deglaciated (?3 years since exposure), unvegetated soils of the Puca Glacier forefield in Southeastern Peru. We evaluated soil properties and examined bacterial community composition in plots before and one year after fertilization. Fertilized soils were then compared to samples from three reference successional transects representing advancing stages of soil development ranging from 5 years to 85 years since exposure. We found that a single application of +NP fertilizer caused the soil bacterial community structure of the three-year old soils to most resemble the 85-year old soils after one year. Despite differences in a variety of soil edaphic properties between fertilizer plots and late successional soils, bacterial community composition of +NP plots converged with late successional communities. Thus, our work suggests a mechanism for microbial succession whereby changes in resource availability drive shifts in community composition, supporting a role for nutrient colimitation in primary succession. These results suggest that nutrients alone, independent of other edaphic factors that change with succession, act as an important control over soil microbial community development, greatly accelerating the rate of succession. PMID:25050551

Knelman, Joseph E; Schmidt, Steven K; Lynch, Ryan C; Darcy, John L; Castle, Sarah C; Cleveland, Cory C; Nemergut, Diana R

2014-01-01

208

Appropriate nutrient supplementation in celiac disease.  

PubMed

Reduced levels of iron, folate, vitamin B12, vitamin D, zinc, and magnesium are common in untreated celiac disease (CD) patients probably due to loss of brush border proteins and enzymes needed for the absorption of these nutrients. In the majority of patients, removal of gluten from the diet leads to histological recovery and normalization of iron, vitamin, and mineral levels. Iron deficiency anemia is the most common extra-intestinal sign of CD and usually resolves with adherence to a gluten-free diet. However, deficiencies of both folate and vitamin B12 may persist in some patients on a gluten-free diet, thus requiring vitamin supplementation to improve subjective health status. Similarly, exclusion of gluten from the diet does not always normalize bone mineral density; in these cases, supplementation of vitamin D and calcium is recommended. Resolution of mucosal inflammation may not be sufficient to abrogate magnesium deficiency. Since gluten-free cereal products have a lower magnesium content as compared with gluten-containing counterparts, a magnesium-enriched diet should be encouraged in CD patients. In this article we discuss the frequency and clinical relevance of nutrient deficiency in CD and whether and when nutrient supplementation is needed. PMID:24195595

Caruso, Roberta; Pallone, Francesco; Stasi, Elisa; Romeo, Samanta; Monteleone, Giovanni

2013-12-01

209

Nutrient sensing and signaling in the yeast Saccharomyces cerevisiae  

PubMed Central

The yeast Saccharomyces cerevisiae has been a favorite organism for pioneering studies on nutrient-sensing and signaling mechanisms. Many specific nutrient responses have been elucidated in great detail. This has led to important new concepts and insight into nutrient-controlled cellular regulation. Major highlights include the central role of the Snf1 protein kinase in the glucose repression pathway, galactose induction, the discovery of a G-protein-coupled receptor system, and role of Ras in glucose-induced cAMP signaling, the role of the protein synthesis initiation machinery in general control of nitrogen metabolism, the cyclin-controlled protein kinase Pho85 in phosphate regulation, nitrogen catabolite repression and the nitrogen-sensing target of rapamycin pathway, and the discovery of transporter-like proteins acting as nutrient sensors. In addition, a number of cellular targets, like carbohydrate stores, stress tolerance, and ribosomal gene expression, are controlled by the presence of multiple nutrients. The protein kinase A signaling pathway plays a major role in this general nutrient response. It has led to the discovery of nutrient transceptors (transporter receptors) as nutrient sensors. Major shortcomings in our knowledge are the relationship between rapid and steady-state nutrient signaling, the role of metabolic intermediates in intracellular nutrient sensing, and the identity of the nutrient sensors controlling cellular growth. PMID:24483210

Conrad, Michaela; Schothorst, Joep; Kankipati, Harish Nag; Van Zeebroeck, Griet; Rubio-Texeira, Marta; Thevelein, Johan M

2014-01-01

210

Anthropogenic nutrients and harmful algae in coastal waters.  

PubMed

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

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

2014-12-15

211

Nature of Random Variation in the Nutrient Composition of Meals  

PubMed Central

The mathematical formulation of nutrient variation in meals in presented by means of random vectors. The primary sources of nutrient variation in unit portions of menu items are identified and expressed in terms of random food-nutrient, random portion size and random ingredient composition variations. A secondary source of nutrient variation can be traced to the random selection process of combining menu items into individual meals from multiple choice menus. The separate as well as the joint effect of these sources on the total variation of the nutrient content of meals is described with the aid of variance-covariance matrices. The investigation is concluded with the formulation of multivariate probability statements concerning the adequacy of the nutrient content of meals relative to the distribution of the nutrient requirements over a given population. PMID:5971545

Balintfy, Joseph L.; Prekopa, Andras

1966-01-01

212

Turbulent nutrient fluxes in the Iceland Basin  

NASA Astrophysics Data System (ADS)

As part of a multidisciplinary cruise to the Iceland Basin in July-August 2007, near to the historical JGOFS Ocean Weather Station India site (˜59° N, ˜19° W), observations were made of vertical turbulent nutrient fluxes around an eddy dipole, a strong mesoscale feature consisting of a cyclonic eddy and an anti-cyclonically rotating mode-water eddy. Investigation of the spatial distribution of vertical turbulent diffusivity around the dipole shows an almost uniform horizontal distribution despite the strong horizontal gradients in water velocity and density observed. An area mean turbulent diffusivity was calculated as 0.21 (95% confidence interval: 0.17-0.26)×10-4 m2 s-1 at the base of the euphotic zone. The vertical turbulent fluxes of three major macro-nutrients into the euphotic zone were calculated as 0.13 (95% confidence interval 0.08-0.22) mmol m-2 day-1 for nitrate, 0.08 (0.05-0.12) mmol m-2 day-1 for silicate and, 8.6 (13.0-5.2 )×10-3 mmol m-2 day-1 for phosphate. The vertical turbulent flux of dissolved iron (dFe) into the euphotic zone was calculated to be 2.6 (95% confidence interval 1.3-4.3)×10-6 mmol m2 day-1. Turbulent macro-nutrient flux is estimated to contribute up to 14% of the deep winter mixing supply of silicate, nitrate and phosphate in the region. The magnitude of turbulent dFe flux is estimated to be at most 8% of the deep winter mixing supply of dFe. Deep winter mixing is hypothesised to supply an adequate amount of iron to fully utilise the deep winter mixed supply of silicate but not the deep winter mixed supply of nitrate. This suggests that while the iron supply may not limit the magnitude of the spring bloom, iron limitation may be occurring post bloom.

Forryan, A.; Martin, A. P.; Srokosz, M. A.; Popova, E. E.; Painter, S. C.; Stinchcombe, M. C.

2012-05-01

213

Biological nutrient removal from dairy wastewater  

SciTech Connect

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.

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

1998-07-01

214

Design of nutrient removal activated sludge systems.  

PubMed

A mechanistic mathematical model for nutrient and organic matter removal was used to describe the behavior of a nitrification denitrification enhanced biological phosphorus removal (NDEBPR) system. This model was implemented in a user-friendly software DESASS (design and simulation of activated sludge systems). A 484-L pilot plant was operated to verify the model results. The pilot plant was operated for three years over three different sludge ages. The validity of the model was confirmed with data from the pilot plant. Also, the utility of DESASS as a valuable tool for designing NDEBPR systems was confirmed. PMID:12906279

Manga, J; Ferrer, J; Seco, A; Garcia-Usach, F

2003-01-01

215

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

Microsoft Academic Search

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

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

2003-01-01

216

A biogeochemical model for phosphorus and nitrogen cycling in the Eastern Mediterranean Sea. Part 2. Response of nutrient cycles and primary production to anthropogenic forcing: 1950-2000  

NASA Astrophysics Data System (ADS)

Anthropogenic inputs of nutrient phosphorus (P) and nitrogen (N) to the Eastern Mediterranean Sea (EMS) increased significantly after 1950. Nonetheless, the EMS remained ultra-oligotrophic, with eutrophication only affecting a restricted number of nearshore areas. To better understand this apparent contradiction, we reconstructed the external inputs of reactive P and N to the EMS for the period 1950 to 2000. Although the inputs associated with atmospheric deposition and river discharge more than doubled, the inflow of surface water from the Western Mediterranean Sea (WMS) remained the dominant source of nutrient P and N to the EMS during the second half of the 20th century. The combined external input of reactive P rose by 24% from 1950 to 1985, followed by a slight decline. In contrast, the external reactive N input increased continuously from 1950 to 2000, with a 62% higher input in 2000 compared to 1950. When imposing the reconstructed inputs to the dynamic model of P and N cycling in the EMS developed in the companion paper, a maximum increase of primary production of only 16% is predicted. According to the model, integrated over the period 1950-2000, outflow of Levantine Intermediate Water (LIW) to the WMS exported the equivalent of about one third of the P supplied in excess of the 1950 input, while another one third was translocated to the Eastern Mediterranean Deep Water (EMDW). Together, both mechanisms efficiently counteracted enhanced P input to the EMS, by drawing nutrient P away from primary producers in the surface waters. Furthermore, between 1950 and 2000, inorganic and organic dissolved N:P ratios increased in all water masses. Thus, the EMS became even more P limited because of anthropogenic nutrient inputs. A model simulation incorporating the circulation changes accompanying the Eastern Mediterranean Transient (EMT) between 1987 and 2000 yielded a 4% increase of EMS primary productivity relative to the baseline scenario.

Powley, H. R.; Krom, M. D.; Emeis, K.-C.; Van Cappellen, P.

2014-11-01

217

Nutrient Management in TexasNutrient Management in Texas Sam FeagleySam Feagley  

E-print Network

,000 plant samples per year~ 10,000 plant samples per year ­­ ~ 6,000 water samples per year~ 6,000 water,bean, lablab, tall fescue, IllinoisIllinois bundleflowerbundleflower, crab grass, partridge pea,, crab grass, partridge pea, sunflower, guar, rice, sugarcane, citrussunflower, guar, rice, sugarcane, citrus #12;Nutrient

218

Mineral nutrients are continuously cycled through organisms and their environment, yet cellular nutrient  

E-print Network

Mineral nutrients are continuously cycled through organisms and their environment, yet cellular by a single amino acid change (Gly149 to Arg) in the essential yeast cell division cycle gene CDC1. The mutant bacteria. The survival of the pathogen during the burst of macrophage respiratory activity is thought

Nelson, Nathan

219

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

Microsoft Academic Search

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

JOHN CARRUTHERS FERGUSON

220

Nutrient Limitation in Northern Gulf of Mexico (NGOM): Phytoplankton Communities and Photosynthesis Respond to Nutrient Pulse  

PubMed Central

Although the Mississippi-Atchafalaya River system exports large amounts of nutrients to the Northern Gulf of Mexico annually, nutrient limitation of primary productivity still occurs offshore, acting as one of the major factors controlling local phytoplankton biomass and community structure. Bioassays were conducted for 48 hrs at two stations adjacent to the river plumes in April and August 2012. High Performance of Liquid Chromatography (HPLC) combined with ChemTax and a Fluorescence Induction and Relaxation (FIRe) system were combined to observe changes in the phytoplankton community structure and photosynthetic activity. Major fluorescence parameters (Fo, Fv/Fm) performed well to reveal the stimulating effect of the treatments with nitrogen (N-nitrate) and with nitrogen plus phosphate (+NPi). HPLC/ChemTax results showed that phytoplankton community structure shifted with nitrate addition: we observed an increase in the proportion of diatoms and prasinophytes and a decrease in cyanobacteria and prymnesiophytes. These findings are consistent with predictions from trait-based analysis which predict that phytoplankton groups with high maximum growth rates (?max) and high nutrient uptake rates (Vmax) readily take advantage of the addition of limiting nutrients. Changes in phytoplankton community structure, if persistent, could trigger changes of particular organic matter fluxes and alter the micro-food web cycles and bottom oxygen consumption. PMID:24551144

Zhao, Yan; Quigg, Antonietta

2014-01-01

221

Nutrient supply and intervertebral disc metabolism.  

PubMed

The metabolic environment of disc cells is governed by the avascular nature of the tissue. Because cellular energy metabolism occurs mainly through glycolysis, the disc cells require glucose for survival and produce lactic acid at high rates. Oxygen is also necessary for cellular activity, although not for survival; its pathway of utilization is unclear. Because the tissues are avascular, disc cells depend on the blood supply at the margins of the discs for their nutrients. The nucleus and inner anulus of the disc are supplied by capillaries that arise in the vertebral bodies, penetrate the subchondral bone, and terminate at the bone-disc junction. Small molecules such as glucose and oxygen then reach the cells by diffusion under gradients established by the balance between the rate of transport through the tissue to the cells and the rate of cellular demand. Metabolites such as lactic acid are removed by the reverse pathway. The concentrations of nutrients farthest from the source of supply can thus be low; oxygen concentrations as low as 1% have been measured in the discs of healthy animals. Although gradients cannot be measured easily in humans, they can be calculated. Measured concentrations in surgical patients are in agreement with calculated values. PMID:16595440

Grunhagen, Thijs; Wilde, Geoffrey; Soukane, Dahbia Mokhbi; Shirazi-Adl, Saeed A; Urban, Jill P G

2006-04-01

222

Lichen substances prevent lichens from nutrient deficiency.  

PubMed

The dibenzofuran usnic acid, a widespread cortical secondary metabolite produced by lichen-forming fungi, was shown to promote the intracellular uptake of Cu(2+) in two epiphytic lichens, Evernia mesomorpha and Ramalina menziesii, from acidic, nutrient-poor bark. Higher Cu(2+) uptake in the former, which produces the depside divaricatic acid in addition to usnic acid, suggests that this depside promotes Cu(2+) uptake. Since Cu(2+) is one of the rarest micronutrients, promotion of Cu(2+) uptake by lichen substances may be crucial for the studied lichens to survive in their nutrient-poor habitats. In contrast, study of the uptake of other metals in E. mesomorpha revealed that the intracellular uptake of Mn(2+), which regularly exceeds potentially toxic concentrations in leachates of acidic tree bark, was partially inhibited by the lichen substances produced by this species. Inhibition of Mn(2+) uptake by lichen substances previously has been demonstrated in lichens. The uptake of Fe(2+), Fe(3+), Mg(2+), and Zn(2+), which fail to reach toxic concentrations in acidic bark at unpolluted sites, although they are more common than Cu(2+), was not affected by lichen substances of E. mesomorpha. PMID:19151928

Hauck, Markus; Willenbruch, Karen; Leuschner, Christoph

2009-01-01

223

[Temporal and spatial variation of water nutrient level after exogenous nutrient input].  

PubMed

In order to study the spatial and temporal variations of nitrogen (N) and phosphorous (P) nutrition in artificial wetlands after a single exogenous nutrient input, 6 mosaic communities of 7 plant species were set up in a cement channel in the greenhouse. After the addition of N and P nutritional solutions, the concentrations of dissolved total nitrogen (DTN), dissolved total phosphorous (DTP), ammonia nitrogen (NH4(+)-N), nitrate nitrogen (NO3(-) -N) and nitrite nitrogen (NO2(-) -N) in the surface, middle, and bottom layers of the bulk water were determined regularly within 22 days. The results show that: (1) the water depth and measuring date have significant effects on nutritional contents while the type of plant communities have no such an influence; (2) the diffusion of nutrient from surface to the middle water layers is relatively slow, which costs 6 days under the current experimental condition; (3) in the bottom water layer, nutritional concentrations had no significant changes except for NO2-N, thus the exogenous nutrient input mainly affects the nutrient contents of surface and middle-level bulk water; (4) DTP and NH4(+) -N contents gradually decline to similar levels that before the nutritional input event until the end of experimental period, though DTN and NO3(-) -N content decrease much more slowly; (5) the fact that NO2(-) -N contents rise in water layers of all depths demonstrates that nitrification and denitrification in the process of N circulation are enhanced. It is concluded that exogenous nutrient inputs not only harm aquatic ecosystems but also directly threat human health. PMID:24946576

Fu, Ling; Zhao, Kai; Wang, Guo-Xiang; Ou, Yuan; Fan, Zhou; Mao, Li-Na; Zhang, Jia; Han, Rui-Ming

2014-04-01

224

Microalgal and cyanobacterial cultivation: the supply of nutrients.  

PubMed

Microalgae and cyanobacteria are a promising new source of biomass that may complement agricultural crops to meet the increasing global demand for food, feed, biofuels and chemical production. Microalgae and cyanobacteria cultivation does not interfere directly with food production, but care should be taken to avoid indirect competition for nutrient (fertilizer) supply. Microalgae and cyanobacteria production requires high concentrations of essential nutrients (C,N,P,S,K,Fe, etc.). In the present paper the application of nutrients and their uptake by microalgae and cyanobacteria is reviewed. The main focus is on the three most significant nutrients, i.e. carbon, nitrogen and phosphorus; however other nutrients are also reviewed. Nutrients are generally taken up in the inorganic form, but several organic forms of them are also assimilable. Some nutrients do not display any inhibition effect on microalgal or cyanobacterial growth, while others, such as NO2 or NH3 have detrimental effects when present in high concentrations. Nutrients in the gaseous form, such as CO2 and NO face a major limitation which is related mainly to their mass transfer from the gaseous to the liquid state. Since the cultivation of microalgae and cyanobacteria consumes considerable quantities of nutrients, strategies to improve the nutrient application efficiency are needed. Additionally, a promising strategy to improve microalgal and cyanobacterial production sustainability is the utilization of waste streams by recycling of waste nutrients. However, major constraints of using waste streams are the reduction of the range of the biomass applications due to production of contaminated biomass and the possible low bio-availability of some nutrients. PMID:25113948

Markou, Giorgos; Vandamme, Dries; Muylaert, Koenraad

2014-11-15

225

Nutrient Pollution of Coastal Rivers, Bays, and Seas  

NSDL National Science Digital Library

This 'Issues in Ecology' article from the Ecological Society of America provides information about the consequences of nutrient enrichment along the US coast. It describes problems such as harmful algal blooms (HABs), anoxia, hypoxia, and dead zones. It explains which nutrients are involved and describes implications of excess nutrients in regions such as the Gulf of Mexico/Mississippi River basin. The article features several color photographs, maps, and diagrams.

Howarth, Robert; Anderson, Donald; Cloern, James; Elfring, Chris; Hopkinson, Charles; Lapointe, Brian

226

Potato growth and yield using nutrient film technique (NFT)  

Microsoft Academic Search

Potato plants, cvs Denali and Norland, were grown in polyvinyl chloride (PVC) trays using a continuous flowing nutrient film\\u000a technique (NFT) to study tuber yield for NASs Controlled Ecological Life Support Systems (CELSS) program. Nutrient solution\\u000a 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,

Raymond M. Wheeler; C. Ross Hinkle; Cheryl L. Mackowiak; John C. Sager; William M. Knott

1990-01-01

227

Sources and fate of nutrients in a subtropical reservoir  

Microsoft Academic Search

This study examined the sources and fate of nutrient inputs from two principal tributaries to the eutrophic subtropical Wivenhoe\\u000a reservoir: an unregulated river and a dammed river with regular releases, during a period of declining reservoir water levels.\\u000a Nutrient budgets were constructed over a period of 6 years, and combined with short-term data on nutrient concentrations and\\u000a forms, and ?15N stable

Michele A. Burford; Susanne A. Green; Andrew J. Cook; Suzanne A. Johnson; Jason G. Kerr; Katherine R. O’Brien

228

ABOVE AND BELOWGROUND INTERACTIONS ARE MEDIATED BY NUTRIENT AVAILABILITY  

Microsoft Academic Search

By influencing nutrient mineralization in the soil, decomposers may affect the performance of plants and their associated herbivores. The strength of above-belowground linkages may therefore depend on the availability of nutrients in ecosystems. We investigated the dependency of decomposer- and leaf-herbivore-mediated changes in plant performance on soil nutrient availability in microcosm systems. In separate treatments, Poa annua was used as

Josephine Haase; Roland Brandl; Stefan Scheu; Martin Schädler

2008-01-01

229

Relationships between eutrophication variables: from nutrient loading to transparency  

Microsoft Academic Search

Monitoring data obtained from 231 freshwater lakes and ponds in the Netherlands, covering the period 1980–1996, were used to analyse the relationships between (a) transparency and chlorophyll-a, and the effect of system characteristics on this relationship, (b) chlorophyll-aand nutrient concentrations, and the effect of biological variables and (c) nutrient concentrations and nutrient loading. (a) Chlorophyll-aimposes a maximum on water transparency,

R. Portielje; D. T. Van der Molen

1999-01-01

230

Physical Transport of Nutrients and the Maintenance of Biological Production  

Microsoft Academic Search

\\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

Richard G. Williams; Michael J. Follows

231

Enhanced Use of Feed and Manure Nutrients in Animal Agriculture  

Microsoft Academic Search

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., soils and crops) and the relative impact of each component's management on the environment. Many livestock operations rely on inexpensive

J. Mark Powell

232

Nutrient utilization and reproductive performance in broiler breeder hens.  

E-print Network

??Experiments were conducted to evaluate the influences of initial body-weight at photostimulation, diet density or feeding level on nutrient utilization and reproductive performance of broiler… (more)

Mendoza Castro, Alexandra Maria

2006-01-01

233

The Plant Ionome Revisited by the Nutrient Balance Concept  

PubMed Central

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

Parent, Serge-Etienne; Parent, Leon Etienne; Egozcue, Juan Jose; Rozane, Danilo-Eduardo; Hernandes, Amanda; Lapointe, Line; Hebert-Gentile, Valerie; Naess, Kristine; Marchand, Sebastien; Lafond, Jean; Mattos, Dirceu; Barlow, Philip; Natale, William

2013-01-01

234

Effect of Animal Manure Amended Spent Grain and Cocoa Husk on Nutrient Status, Growth and Yied of Tomato  

Microsoft Academic Search

2 Abstract: Combined use of crop and animal wastes is necessary in order to obtain adequate amount of organic manure for use in crop production. Hence field experiments were conducted at two sites in Akure, Southwest Nigeria to compare effect of NPK (15-5-15) fertilizer (200 kg ha ? ) and each of Spent Grain (SG) and ground 1 Cocoa Husk

S. O. Ojeniyi; S. A. Odedina

235

Nitrate and nutrient accumulation in two varieties of bermudagrass (Cynodon dactylon (L.) Pers.) as influenced by soil applied fertilizer nutrients  

E-print Network

NITRATE AND NUTRIENT ACCUMULATION IN TWO VARIETIES OF BDRKIDllddlidd (C~d ~dt L (L. ) F . ) AS INFLUENCED BY SOIL APPLIED FERTILIZER NUTRIENTS A Thesis By DALE A. LOVELACE Submitted to the Graduate College of the TEXAS A6H UNIVERSITY... in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE January 1968 Major Subject: Agronomy NITRATE AND NUTRIENT ACCUMULATION IN TWO VARIETIES DP EEEEDDECEEEE EC~d ~dt L EL. ) P . ) AS INFLUENCED BY SOIL APPLIED FERTILIZER NUTRl...

Lovelace, Dale Allen

2012-06-07

236

Lateral Diffusion of Nutrients by Mammalian Herbivores in Terrestrial Ecosystems  

PubMed Central

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

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

2013-01-01

237

Leptin regulates the reward value of nutrient  

PubMed Central

We developed an assay for quantifying the reward value of nutrient and used it to analyze the effects of metabolic state and leptin. In this assay, mice chose between two sippers, one of which dispensed water and was coupled to optogenetic activation of dopaminergic (DA) neurons and the other of which dispensed natural or artificial sweeteners. This assay measured the reward value of sweeteners relative to lick-induced optogenetic activation of DA neurons. Mice preferred optogenetic stimulation of DA neurons to sucralose, but not to sucrose. However, the mice preferred sucralose plus optogenetic stimulation versus sucrose. We found that food restriction increased the value of sucrose relative to sucralose plus optogenetic stimulation, and that leptin decreased it. Our data suggest that leptin suppresses the ability of sucrose to drive taste-independent DA neuronal activation and provide new insights into the mechanism of leptin's effects on food intake. PMID:22081158

Domingos, Ana I; Vaynshteyn, Jake; Voss, Henning U; Ren, Xueying; Gradinaru, Viviana; Zang, Feng; Deisseroth, Karl; de Araujo, Ivan E; Friedman, Jeffrey

2014-01-01

238

Porous tube plant nutrient delivery system development: A device for nutrient delivery in microgravity  

NASA Technical Reports Server (NTRS)

The Porous Tube Plant Nutrient Delivery Systems or PTPNDS (U.S. Patent #4,926,585) has been under development for the past six years with the goal of providing a means for culturing plants in microgravity, specifically providing water and nutrients to the roots. Direct applications of the PTPNDS include plant space biology investigations on the Space Shuttle and plant research for life support in the Space Station Freedom. In the past, we investigated various configurations, the suitability of different porous materials, and the effects of pressure and pore size on plant growth. Current work is focused on characterizing the physical operation of the system, examining the effects of solution aeration, and developing prototype configurations for the Plant Growth Unit (PGU), the flight system for the Shuttle mid-deck. Future developments will involve testing on KC-135 parabolic flights, the design of flight hardware and testing aboard the Space Shuttle.

Dreschel, T. W.; Brown, C. S.; Piastuch, W. C.; Hinkle, C. R.; Knott, W. M.

1994-01-01

239

Original article Mineral nutrients of beech (Fagus sylvatica) bark  

E-print Network

­ Concentration of nutrients and balance between nutrients in trees can affect tree vitality, and are dependent and decreased concentrations of Mn and B. Negative influence from N fertilization could be traced la Suède. La concentration et l'équilibre des éléments minéraux dans les arbres peut affecter leur

Boyer, Edmond

240

MACRO NUTRIENT Hans-Rudolf Berthoud, Ph.D.  

E-print Network

Minerals 0.3-6.0% Calcium Ca++ Soil Minerals 0.1-3.0% Magnesium Mg++ Soil Minerals 0.05-1.0% Sulfur SO4 · Nutrients are ranked from most deficient to most excessive Disadvantages · Computations are complicated 2. B 3. K 4. Mg #12;Mobile vs. Immobile Nutrients #12;What deficiency is shown in these photos? 1. K

Galef Jr., Bennett G.

241

Insights into Digestion and Absorption of Major Nutrients in Humans  

ERIC Educational Resources Information Center

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 nonscientists know the details about how various…

Goodman, Barbara E.

2010-01-01

242

Ceratophyllum demersum – phosphorus interactions in nutrient enriched aquaria  

Microsoft Academic Search

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.

Paola Lombardo; G. Dennis Cooke

2003-01-01

243

Nutrient Exchange through Hyphae in Intercropping Systems Affects Yields  

ERIC Educational Resources Information Center

Arbuscular mycorrhizae fungi (AMF) play a large role in the current understanding of the soil ecosystem. They increase nutrient and water uptake, improve soil structure, and form complex hyphal networks that transfer nutrients between plants within an ecosystem. Factors such as species present, the physiological balance between the plants in the…

Thun, Tim Von

2013-01-01

244

Nutrient status of rhizosphere and phosphorus response of radish  

Microsoft Academic Search

Radish (Raphanus sativus L.) exhibits a high efficiency in the utilization of sparingly?soluble phosphates. A greenhouse experiment was designed to investigate the growth response of radish to different phosphorus (P) sources and the nutrient status of the rhizosphere associated with radish growth and nutrient absorption. Radish plants were grown in pots with the roots confined in rhizobags, in such a

Jianlin Wang; Zhichao Luo; Richard H. Loeppert

1995-01-01

245

BENTHIC NUTRIENT FLUX IN A SMALL ESTUARY IN NORTHWESTERNFLORIDA (USA)  

EPA Science Inventory

Benthic Nutrient Flux in a Small Estuary in Northwestern Florida(USA).Gulf and Caribbean Research 18, 15-25, 2006. Benthic nutrient fluxes of ammonium (NH4+), nitrite/nitrate (NO2-+NO3-), phosphate (PO4-), and dissolved silica (DSi) were measured in Escambia Bay, an estuar...

246

Biotechnology of nutrient uptake and assimilation in plants.  

PubMed

Plants require a complex balance of mineral nutrients to reproduce successfully. Because the availability of many of these nutrients in the soil is compromised by several factors, such as soil pH, cation presence, and microbial activity, crop plants depend directly on nutrients applied as fertilizers to achieve high yields. However, the excessive use of fertilizers is a major environmental concern due to nutrient leaching that causes water eutrophication and promotes toxic algae blooms. This situation generates the urgent need for crop plants with increased nutrient use efficiency and better-designed fertilization schemes. The plant biology revolution triggered by the development of efficient gene transfer systems for plant cells together with the more recent development of next-generation DNA and RNA sequencing and other omics platforms have advanced considerably our understanding on the molecular basis of plant nutrition and how plants respond to nutritional stress. To date, genes encoding sensors, transcription factors, transporters, and metabolic enzymes have been identified as potential candidates to improve nutrient use efficiency. In addition, the study of other genetic resources, such as bacteria and fungi, allows the identification of alternative mechanisms of nutrient assimilation, which are potentially applicable in plants. Although significant progress in this respect has been achieved by conventional breeding, in this review we focus on the biotechnological approaches reported to date aimed at boosting the use of the three most limiting nutrients in the majority of arable lands: nitrogen, phosphorus, and iron. PMID:24166442

López-Arredondo, Damar L; Leyva-González, Marco A; Alatorre-Cobos, Fulgencio; Herrera-Estrella, Luis

2013-01-01

247

Stability and preservation of primary calibration solutions of nutrients  

Microsoft Academic Search

In the absence of commercially available calibration solutions in a seawater matrix, the accurate determination of concentrations of nutrients (nitrate, nitrite, ammonia, phosphate, silicate) relies primarily on laboratory calibration solutions, especially primary salt solutions. Their stability is therefore a main factor for quality assurance of data. Since the existing information on nutrient calibration solution stability does not refer to published

Alain Aminot; Roger Kérouel

1996-01-01

248

Primary Productivity Regime and Nutrient Removal in the Danube Estuary  

Microsoft Academic Search

The primary productivity regime, as well as the distribution of dissolved inorganic nutrients and particulate organic matter in the Danube estuary, were investigated during several cruises at different discharge regimes of the Danube River. The shallowness of the upper surface layer due to insignificant tidal mixing and strong stratification of the Danube estuary, as well as the high nutrient concentrations,

C. Humborg

1997-01-01

249

Nutrient Enhancement Peter A. Bisson, Research Fish Biologist  

E-print Network

to freshwater food webs showed that nutrients from salmon carcasses were an important contributor to aquatic to transmit fish diseases or persistent organic pollutants to streams, and to increase nutrient loading. Trotter. 2001. Pacific salmon and wildlife ­ ecological contexts, relationships, and implications

250

Livestock Nutrient Management Concerns: Regulatory and Legislative Overview  

Microsoft Academic Search

A greater focus on manure nutrient disposition from concentrated animal-feeding opera- tions has developed from environmentalists, concerned citizens, and regulatory agencies. The establishment and enforcement of manure nutrient regulations will alter the future of livestock production. Proposed legislation and strategies may provide a false sense of security regarding environmental preservation or restoration and may impose monitoring and record keeping on

Deanne Meyer; D. Denise Mullinax

251

Can ectomycorrhizal weathering activity respond to host nutrient demands?  

E-print Network

Review Can ectomycorrhizal weathering activity respond to host nutrient demands? Nicholas P weathering Nutrient demand a b s t r a c t Ectomycorrhizal fungi may make a significant contribution to mineral weathering in temperate and boreal forests. It is important to know how this weathering activity

Bruns, Tom

252

Effects of acid rain on forest nutrient status  

Microsoft Academic Search

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.

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

1982-01-01

253

Study of diaphyseal nutrient foramina in human long bones  

Microsoft Academic Search

A study was done to determine the number, size, direction, exact site and position of the nutrient foramina in human long bones. The position of all nutrient foramina observed was on the flexor aspect and was more or less around a fixed area, but the exact spot varied considerably. Two foramina were much more frequent in the femur, clavicle and

G. S. Longia; M. L. Ajmani; S. K. Saxena; R. J. Thomas

1980-01-01

254

ORIGINAL ARTICLE Spatial variability of soil organic matter and nutrients  

E-print Network

(GIS). The spatial vari- ability of soil organic matter (SOM), total nitrogen (TN) and available these soil properties. Maps of SOM and TN were generated through interpolation of measured values by ordinary Á Semivariogram Á SOM and nutrients Á Spatial variability Introduction Soil nutrient level

Zhang, Minghua

255

Nutrient addition to enhance biological treatment of greywater  

Microsoft Academic Search

This study compares the chemical oxygen demand (COD) removal and respiration rates of a microbial population treating real and synthetic greywaters dosed with nutrient supplements. The nutrient composition of the real and synthetic greywaters was analysed and the dosing regime for nitrogen, phosphorus and a range of trace metals planned accordingly. The doses consisted of eight single additives (macronutrients and

Bruce Jefferson; Joanna E Burgess; Aude Pichon; Joanne Harkness; Simon J Judd

2001-01-01

256

Productivity and nutrient cycling in bioenergy cropping systems  

Microsoft Academic Search

One of the greatest obstacles confronting large-scale biomass production for energy applications is the development of cropping systems that balance the need for increased productive capacity with the maintenance of other critical ecosystem functions including nutrient cycling and retention. To address questions of productivity and nutrient dynamics in bioenergy cropping systems, we conducted two sets of field experiments during 2005-2007,

Andrew Howard Heggenstaller

2008-01-01

257

Nutrient quality of fast food kids meals1-4  

Microsoft Academic Search

Background: Exposure of children to kids meals at fast food res- taurants is high; however, the nutrient quality of such meals has not been systematically assessed. Objective: We assessed the nutrient quality of fast food meals marketed to young children, ie, \\

Sharon I O'Donnell; Sharon L Hoerr; Jason A Mendoza; Eugenia Tsuei Goh

258

Phytoplankton growth and stoichiometry under multiple nutrient limitation  

Microsoft Academic Search

Phytoplankton growth and stoichiometry depend on the availability of multiple nutrients. We use a mathematical model of phytoplankton with flexible stoichiometry to explain patterns of phytoplankton composition in chemostat experiments and nutrient drawdown dynamics that are found in the field. Exponential growth and equilibrium represent two distinct phases, each amenable to mathematical analysis. In a chemostat at a fixed dilution

Christopher A. Klausmeier; Elena Litchman; Simon A. Levin

2004-01-01

259

The New Nutrient Management What It Means for You  

E-print Network

out between fingers has slick feeling 3,0005,0006,00010,000Fine soil texture In Field Wet Soil Description Upon Squeezing 30%30%% Crop Residue Cover Wet soil rate gal./ac. Wet soil rate gal Nutrient Management · Apply nutrients according to annual NM plan using UW soil test recommendations

Balser, Teri C.

260

Association of arsenic with nutrient elements in rice plants.  

PubMed

Rice is the main cereal crop that feeds half of the world's population, and two thirds of the Chinese population. Arsenic (As) contamination in paddy soil and irrigation water elevates As concentration in rice grains, thus rice consumption is an important As intake route for populations in south and south-east Asia, where rice is the staple food. In addition to direct toxicity of As to human, As may limit the accumulation of micro-nutrients in rice grains, such as selenium (Se) and zinc (Zn). These micro-nutrients are essential for humans, while mineral deficiencies, especially iron (Fe) and Zn, are prevalent in China. Therefore, it is important to understand the interactions between As and micro-nutrients in rice plants, which is the principal source of these nutrients for people on rice diets. In addition, during the processes of As uptake, translocation and transformation, the status of macro-nutrients (e.g. silicon (Si), phosphors (P), sulfur (S)) are important factors affecting As dynamics in soil-plant systems and As accumulation in rice grains. Recently, synchrotron-based spectroscopic techniques have been applied to map the distribution of As and nutrient elements in rice plants, which will aid to understand how As are accumulated, complexed and transported within plants. This paper reviews the interactions between As and macro-nutrients, as well as micro-nutrients in rice plants. PMID:23771154

Duan, Guilan; Liu, Wenju; Chen, Xueping; Hu, Ying; Zhu, Yongguan

2013-06-01

261

Optimal foraging when regulating intake of multiple nutrients  

Microsoft Academic Search

There is growing evidence that, rather than maximizing energy intake subject to constraints, many animals attempt to regulate intake of multiple nutrients independently. In the complex diets of animals such as herbivores, the consumption of nutritionally imbalanced foods is sometimes inevitable, forcing trade-offs between eating too much of nutrients present in the foods in relative excess against too little of

Stephen J. Simpson; Richard M. Sibly; Kwang Pum Lee; Spencer T. Behmer; David Raubenheimer

2004-01-01

262

Managing Manure Nutrients Through Multi-crop Forage Production  

Microsoft Academic Search

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

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

263

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...

264

Comparison of nutrients release among some maricultured animals  

Microsoft Academic Search

Integrated mariculture is a feasible method to maintain sustainable and high productivity of aquaculture. The choice of cultured animals and biofilters in the integrated system has to be made on the basis of their nutrient release rates and the clearance rate of each component of the system. We are examining the nutrient release rates among fish (mangrove snapper, Lutjanus russeli,

Pei-Yuan Qian; Madeline C. S Wu; I-Hsun Ni

2001-01-01

265

Mariculture: significant and expanding cause of coastal nutrient enrichment  

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

266

Nutrient dynamics in Amazon shelf waters: results from AMASSEDS  

Microsoft Academic Search

Four hydrographic cruises were conducted on the Amazon shelf as part of the AMASSEDS field program. During each cruise, approximately 55 stations were occupied and nutrients, as well as other hydrographic parameters, were measured. The results of this time series sampling program indicate that the nutrient concentrations in the riverine end-member (silicate = 144 ?mol kg?1, phosphate = 0.7 ?mol

David J. Demaster; Robert H. Pope

1996-01-01

267

Medication-Nutrient Interactions and Individuals with Special Healthcare Needs  

ERIC Educational Resources Information Center

Many children and adults with special healthcare needs receive one or more medications on a regular basis. Parents and healthcare professionals who care for these individuals should be aware of each medication and potential interactions with foods/nutrients. Those who require long term or multiple medications are at highest risk for drug-nutrient…

Brizee, Lori S.

2008-01-01

268

Nutrient availability and cocoyam yield under different tillage practices  

Microsoft Academic Search

Research information on the effect of tillage systems on cocoyam (Xanthosoma sagittifolium (L.) Schott) growth, nutrient status and yield is lacking in Africa. The effects of zero tillage with mulch, zero tillage without mulch, manual mounding, manual ridging and conventional tillage on cocoyam yield, growth and nutrient availability were compared during 2 years on an Alfisol (Oxic Tropuldaf) at Owo

T. M. Agbede

2008-01-01

269

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

NASA Technical Reports Server (NTRS)

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.

Savage, Wayne

1998-01-01

270

Nutrient streams in the North Atlantic: Advective pathways of inorganic and dissolved organic nutrients  

NASA Astrophysics Data System (ADS)

The Gulf Stream provides a `nutrient stream,' an advective flux of nutrients carried in sub-surface waters, redistributing nutrients from the tropics to the mid latitudes. There is a dramatic downstream strengthening in the full depth, volume and nitrate transport diagnosed from synoptic measurements along three sections: 32 Sv and 300 kmol s-1 at 27°N, increasing to 66.7 Sv and 940 kmol s-1 at 35.5°N, and 149.5 Sv and 2100 kmol s-1 at 36.5°N; the transport estimates have uncertainties reaching 10% of their values. The transport-weighted nitrate concentration carried by the Gulf Stream generally decreases downstream in light layers (?? < 26.8), but increases in denser layers between 35.5°N and 36.5°N. The fraction of nutrients from regeneration within the upper thermocline slightly decreases downstream between 35.5°N and 36.5°N. Hence, the downstream variations in the nitrate concentrations carried by the Gulf Stream are probably due to lateral exchange along isopycnals, rather than diapycnal transfer or biological consumption and regeneration. The Gulf Stream also transports dissolved organic nitrogen (DON) northward within lighter upper waters, providing up to 26% of the total nitrogen transport. An accompanying model study reveals coherent nitrate and DON streams, including significant lateral exchange, running from the tropics along the western boundary of the subtropical gyre and following the separated jet along the inter-gyre boundary. The combined nitrate and DON transport along light surfaces (?? < 26.8) remains within the subtropical gyre, while the larger nitrate transport along denser surfaces passes into the subpolar gyre, sustaining high-latitude productivity.

Williams, Richard G.; McDonagh, Elaine; Roussenov, Vassil M.; Torres-Valdes, Sinhue; King, Brian; Sanders, Richard; Hansell, Dennis A.

2011-12-01

271

Linkages between nutrients and assemblages of macroinvertebrates and fish in wadeable streams: Implication to nutrient criteria development  

USGS Publications Warehouse

We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient criteria development; and (3) evaluate the importance of nutrients in influencing biological assemblages relative to other physicochemical factors at different spatial scales. Twenty-three of the 35 fish and 18 of the 26 macroinvertebrate measures significantly correlated (P < 0.05) with at least one nutrient measure. Percentages of carnivorous, intolerant, and omnivorous fishes, index of biotic integrity, and salmonid abundance were fish measures correlated with the most nutrient measures and had the highest correlation coefficients. Percentages of Ephemeroptera-Plecoptera-Trichoptera individuals and taxa, Hilsenhoff biotic index, and mean tolerance value were macroinvertebrate measures that most strongly correlated with the most nutrient measures. Selected biological measures showed clear trends toward degradation as concentrations of phosphorus and nitrogen increased, and some measures showed clear thresholds where biological measures changed drastically with small changes in nutrient concentrations. Our selected environmental factors explained 54% of the variation in the fish assemblages. Of this explained variance, 46% was attributed to catchment and instream habitat, 15% to nutrients, 3% to other water quality measures, and 36% to the interactions among all the environmental variables. Selected environmental factors explained 53% of the variation in macroinvertebrate assemblages. Of this explained variance, 42% was attributed to catchment and instream habitat, 22% to nutrients, 5% to other water quality measures, and 32% to the interactions among all the environmental variables. ?? 2006 Springer Science+Business Media, Inc.

Wang, L.; Robertson, D.M.; Garrison, P.J.

2007-01-01

272

Nutrient mitigation capacity in Mississippi Delta, USA drainage ditches.  

PubMed

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 capacity of a vegetated (V) and non-vegetated (NV) agricultural drainage ditch of similar size and landform in the Mississippi Delta. While no statistically significant differences in ammonium, nitrate, or dissolved inorganic phosphorus mitigation between the two ditches existed, there were significant differences in total inorganic phosphorus percent load reductions (V: 36% +/- 4; NV: 71% +/- 4). However, both agricultural drainage ditches were able to mitigate nutrients, thus reducing the load reaching downstream aquatic receiving systems. Further studies examining ecosystem dynamics within drainage ditches such as sediment and plant nutrient partitioning, as well as microbial processes involved, are needed to provide a better understanding of natural nutrient variability, seasonality and flux. PMID:19656598

Moore, M T; Kröger, R; Locke, M A; Cullum, R F; Steinriede, R W; Testa, S; Lizotte, R E; Bryant, C T; Cooper, C M

2010-01-01

273

Modeling Natural Stream Nutrient Concentrations from Landscape Predictors  

NASA Astrophysics Data System (ADS)

Understanding how much land use change has affected nutrient concentrations in aquatic ecosystems requires a way of estimating the nutrient concentrations that were present in these systems before they were altered. Pre-alteration data are generally not available, but models that associate natural landscape variation with stream nutrient concentrations can be used to predict natural nutrient concentrations. These models can also provide insight into which processes are primarily responsible for observed natural spatial and temporal variability in stream nutrient concentrations. We used data from 782 reference sites across the western USA to develop empirical models that predict natural, base-flow concentrations of total phosphorus (TP) and total nitrogen (TN). Models were built using Random Forests, a nonparametric regression technique that accounts for both interactions between variables and non-linear relationships. We developed candidate predictor variables associated with nutrient sources, sinks, or other processes potentially affecting nutrient concentrations among sites. Factors associated with watershed geology and P availability were the most important predictors of TP. Climate and co-precipitates were less important predictors. TN concentrations were equally associated with climate, atmospheric deposition, and vegetation phenology. Both models were relatively accurate (Root Mean Squared Errors < 12% of the range of observations for independent validation sites) and made better predictions than previous models of natural nutrient concentrations. However, the models were not very precise (r2 = 0.46 for the TP model, and r2 = 0.23 for the TN model). An analysis of the sources of variation showed that our models accounted for a majority of the spatial variation in nutrient concentrations, and much of the imprecision was due to temporal or measurement variation in nutrient concentrations.

Olson, J. R.; Hawkins, C. P.

2012-12-01

274

The nutrient density approach to healthy eating: challenges and opportunities.  

PubMed

The term 'nutrient density' for foods/beverages has been used loosely to promote the Dietary Guidelines for Americans. The 2010 Dietary Guidelines for Americans defined 'all vegetables, fruits, whole grains, fat-free or low-fat milk and milk products, seafood, lean meats and poultry, eggs, beans and peas (legumes), and nuts and seeds that are prepared without added solid fats, added sugars, and sodium' as nutrient dense. The 2010 Dietary Guidelines for Americans further states that nutrient-dense foods and beverages provide vitamins, minerals and other substances that may have positive health effects with relatively few (kilo)calories or kilojoules. Finally, the definition states nutrients and other beneficial substances have not been 'diluted' by the addition of energy from added solid fats, added sugars or by the solid fats naturally present in the food. However, the Dietary Guidelines Advisory Committee and other scientists have failed to clearly define 'nutrient density' or to provide criteria or indices that specify cut-offs for foods that are nutrient dense. Today, 'nutrient density' is a ubiquitous term used in the scientific literature, policy documents, marketing strategies and consumer messaging. However, the term remains ambiguous without a definitive or universal definition. Classifying or ranking foods according to their nutritional content is known as nutrient profiling. The goal of the present commentary is to address the research gaps that still exist before there can be a consensus on how best to define nutrient density, highlight the situation in the USA and relate this to wider, international efforts in nutrient profiling. PMID:25166614

Nicklas, Theresa A; Drewnowski, Adam; O'Neil, Carol E

2014-12-01

275

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

Microsoft Academic Search

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

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

2011-01-01

276

Comparison of Nutrient Content and Cost of Home-Packed Lunches to Reimbursable School Lunch Nutrient Standards and Prices  

ERIC Educational Resources Information Center

Purpose: The purpose of this study was to compare nutrient content and cost of home-packed lunches to nutrient standards and prices for reimbursable school lunches. Methods: Researchers observed food and beverage contents of 333 home packed lunches at four north Texas elementary schools. Nutritionist Pro was used to analyze lunches for calories,…

Johnson, Cara M.; Bednar, Carolyn; Kwon, Junehee; Gustof, Alissa

2009-01-01

277

Nutrient management effects on sweetpotato genotypes under controlled environment  

NASA Technical Reports Server (NTRS)

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.

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

1996-01-01

278

SUSPENDED AND BENTHIC SEDIMENT RELATIONSHIPS IN THE YAQUINA ESTUARY, OREGON: NUTRIENT PROCESSING  

EPA Science Inventory

Measurements of nutrient loading and subsequent nutrient processing are fundamental for determining biogeochemical processes in rivers and estuaries. In Oregon coastal watersheds, nutrient transport is strongly seasonal with up to 94% of the riverine dissolved nitrate and silic...

279

Incidence of nutrient canals in hypertensive patients: A radiographic study  

PubMed Central

Objectives: To determine if any correlation exists in the presence of nutrient canals in hypertensive patients and nonhypertensive patients, to compare the incidence of nutrient canals in different age groups, and also to compare the incidence of nutrient canals between dentulous and edentulous patients. Materials and Methods: This study was carried out on patients, who were divided into a control group comprising of healthy individuals, without history of hypertension and a study group of patients with the history of hypertension. The necessary information like age of the patient, presence or absence of hypertension, its duration, and blood pressure were recorded. An intraoral periapical radiograph of lower anterior region was made using bisecting angle technique and was interpreted. The presence or absence of nutrient canals, bone loss, and the levels of bone loss were recorded. The results so obtained were subjected to statistical analysis. Results: We found that the incidence of nutrient canals was statistically higher in the study group (55.2%) as compared to the control group (36.2%). The incidence of nutrient canals was also found to be increased with, the age till 60 years, amount of alveolar bone loss and in edentulous patients. Conclusion: Hypertension being one of the most commonly encountered medical problems in dental practice and many cases being undiagnosed, the presence of nutrient canal though not entirely indicative of hypertension, should increase the suspicion of the condition to be investigated further. PMID:24678218

Kumar, Vinod R.; Naik, Raghavendra Mahadev; Singh, Rajesh T.; Guruprasad, Yadavalli

2014-01-01

280

Nutrient enrichment affects the mechanical resistance of aquatic plants  

PubMed Central

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

Puijalon, Sara

2012-01-01

281

Water and nutrient acquisition by roots and canopies  

SciTech Connect

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.

Oren, R.; Sheriff, D.W.

1995-07-01

282

The Micro and Macro of Nutrients across Biological Scales.  

PubMed

During the past decade, we have gained new insights into the profound effects that essential micronutrients and macronutrients have on biological processes ranging from cellular function, to whole-organism performance, to dynamics in ecological communities, as well as to the structure and function of ecosystems. For example, disparities between intake and organismal requirements for specific nutrients are known to strongly affect animal physiological performance and impose trade-offs in the allocations of resources. However, recent findings have demonstrated that life-history allocation trade-offs and even microevolutionary dynamics may often be a result of molecular-level constraints on nutrient and metabolic processing, in which limiting reactants are routed among competing biochemical pathways. In addition, recent work has shown that complex ecological interactions between organismal physiological states such as exposure to environmental stressors and infectious pathogens can alter organismal requirements for, and, processing of, nutrients, and even alter subsequent nutrient cycling in ecosystems. Furthermore, new research is showing that such interactions, coupled with evolutionary and biogeographical constraints on the biosynthesis and availability of essential nutrients and micronutrients play an important, but still under-studied role in the structuring and functioning of ecosystems. The purpose of this introduction to the symposium "The Micro and Macro of Nutrient Effects in Animal Physiology and Ecology" is to briefly review and highlight recent research that has dramatically advanced our understanding of how nutrients in their varied forms profoundly affect and shape ecological and evolutionary processes. PMID:24935988

Warne, Robin W

2014-11-01

283

Neural regulation of intestinal nutrient absorption.  

PubMed

The nervous system and the gastrointestinal (GI) tract share several common features including reciprocal interconnections and several neurotransmitters and peptides known as gut peptides, neuropeptides or hormones. The processes of digestion, secretion of digestive enzymes and then absorption are regulated by the neuro-endocrine system. Luminal glucose enhances its own absorption through a neuronal reflex that involves capsaicin sensitive primary afferent (CSPA) fibres. Absorbed glucose stimulates insulin release that activates hepatoenteric neural pathways leading to an increase in the expression of glucose transporters. Adrenergic innervation increases glucose absorption through ?1 and ? receptors and decreases absorption through activation of ?2 receptors. The vagus nerve plays an important role in the regulation of diurnal variation in transporter expression and in anticipation to food intake. Vagal CSPAs exert tonic inhibitory effects on amino acid absorption. It also plays an important role in the mediation of the inhibitory effect of intestinal amino acids on their own absorption at the level of proximal or distal segment. However, chronic extrinsic denervation leads to a decrease in intestinal amino acid absorption. Conversely, adrenergic agonists as well as activation of CSPA fibres enhance peptides uptake through the peptide transporter PEPT1. Finally, intestinal innervation plays a minimal role in the absorption of fat digestion products. Intestinal absorption of nutrients is a basic vital mechanism that depends essentially on the function of intestinal mucosa. However, intrinsic and extrinsic neural mechanisms that rely on several redundant loops are involved in immediate and long-term control of the outcome of intestinal function. PMID:21854830

Mourad, Fadi H; Saadé, Nayef E

2011-10-01

284

Nutrient Acquisition and Metabolism by Campylobacter jejuni  

PubMed Central

The gastrointestinal pathogen Campylobacter jejuni is able to colonize numerous different hosts and compete against the gut microbiota. To do this, it must be able to efficiently acquire sufficient nutrients from its environment to support its survival and rapid growth in the intestine. However, despite almost 50?years of research, many aspects as to how C. jejuni accomplishes this feat remain poorly understood. C. jejuni lacks many of the common metabolic pathways necessary for the use of glucose, galactose, or other carbohydrates upon which most other microbes thrive. It does however make efficient use of citric acid cycle intermediates and various amino acids. C. jejuni readily uses the amino acids aspartate, glutamate, serine, and proline, with certain strains also possessing additional pathways allowing for the use of glutamine and asparagine. More recent work has revealed that some C. jejuni strains can metabolize the sugar l-fucose. This finding has upset years of dogma that C. jejuni is an asaccharolytic organism. C. jejuni also possesses diverse mechanisms for the acquisition of various transition metals that are required for metabolic activities. In particular, iron acquisition is critical for the formation of iron–sulfur complexes. C. jejuni is also unique in possessing both molybdate and tungsten cofactored proteins and thus has an unusual regulatory scheme for these metals. Together these various metabolic and acquisition pathways help C. jejuni to compete and thrive in wide variety of hosts and environments. PMID:22919597

Stahl, Martin; Butcher, James; Stintzi, Alain

2012-01-01

285

Diagnosis of nutrient imbalances with vector analysis in agroforestry systems.  

PubMed

Agricultural intensification has had unintended environmental consequences, including increased nutrient leaching and surface runoff and other agrarian-derived pollutants. Improved diagnosis of on-farm nutrient dynamics will have the advantage of increasing yields and will diminish financial and environmental costs. To achieve this, a management support system that allows for site-specific rapid evaluation of nutrient production imbalances and subsequent management prescriptions is needed for agroecological design. Vector diagnosis, a bivariate model to depict changes in yield and nutritional response simultaneously in a single graph, facilitates identification of nutritional status such as growth dilution, deficiency, sufficiency, luxury uptake, and toxicity. Quantitative data from cocoa agroforestry systems and pigeonpea intercropping trials in Ghana and Tanzania, respectively, were re-evaluated with vector analysis. Relative to monoculture, biomass increase in cocoa ( L.) under shade (35-80%) was accompanied by a 17 to 25% decline in P concentration, the most limiting nutrient on this site. Similarly, increasing biomass with declining P concentrations was noted for pigeonpea [ (L). Millsp.] in response to soil moisture availability under intercropping. Although vector analysis depicted nutrient responses, the current vector model does not consider non-nutrient resource effects on growth, such as ameliorated light and soil moisture, which were particularly active in these systems. We revisit and develop vector analysis into a framework for diagnosing nutrient and non-nutrient interactions in agroforestry systems. Such a diagnostic technique advances management decision-making by increasing nutrient precision and reducing environmental issues associated with agrarian-derived soil contamination. PMID:21546672

Isaac, Marney E; Kimaro, Anthony A

2011-01-01

286

Natural selection for costly nutrient recycling in simulated microbial metacommunities.  

PubMed

Recycling of essential nutrients occurs at scales from microbial communities to global biogeochemical cycles, often in association with ecological interactions in which two or more species utilise each others' metabolic by-products. However, recycling loops may be unstable; sequences of reactions leading to net recycling may be parasitised by side-reactions causing nutrient loss, while some reactions in any closed recycling loop are likely to be costly to participants. Here we examine the stability of nutrient recycling loops in an individual-based ecosystem model based on microbial functional types that differ in their metabolism. A supplied nutrient is utilised by a "source" functional type, generating a secondary nutrient that is subsequently used by two other types-a "mutualist" that regenerates the initial nutrient at a growth rate cost, and a "parasite" that produces a refractory waste product but does not incur any additional cost. The three functional types are distributed across a metacommunity in which separate patches are linked by a stochastic diffusive migration process. Regions of high mutualist abundance feature high levels of nutrient recycling and increased local population density leading to greater export of individuals, allowing the source-mutualist recycling loop to spread across the system. Individual-level selection favouring parasites is balanced by patch-level selection for high productivity, indirectly favouring mutualists due to the synergistic productivity benefits of the recycling loop they support. This suggests that multi-level selection may promote nutrient cycling and thereby help to explain the apparent ubiquity and stability of nutrient recycling in nature. PMID:22842011

Boyle, Richard A; Williams, Hywel T P; Lenton, Timothy M

2012-11-01

287

External nutrient sources, internal nutrient pools, and phytoplankton production in Chesapeake Bay  

SciTech Connect

External nutrient loadings, internal nutrient pools, and phytoplankton production were examined for three major subsystems of the Chesapeake Bay Estuary-the upper Mainstem, the Patuxent Estuary, and the Potomac Estuary-during 1985-1989. The atomic nitrogen to phosphorus ratios (TN:TP) of total loads were 51, 29 and 35, respectively. Most of these loads entered at the head of the estuaries from riverine sources and major wastewater treatment plants. Seven-16% of the nitrogen load entered the head of each estuary as particulate matter in contrast to 48-69% for phosphorus. The difference seems to favor a greater loss of phosphorus than nitrogen through sedimentation and burial. A major storm event in the Potomac watershed greatly increased the particulate fraction of nitrogen and phosphorus and lowered the TN:TP in the river-borne loads and accounted for 11% of the nitrogen and 31% of the phosphorus delivered to the estuary by the Potomac River during the entire 60- month period examined here. Within the Mainstem estuary, salinity dilution plots revealed strong net sources of ammonium and phosphate in the oligohaline to upper mesohaline region. indicating considerable internal recycling of nutrients to surface waters. A net sink of nitrate was indicated during summer. Phytoplankton biomass in the mesohaline Mainstem reached a peak in spring and was relatively constant throughout the other seasons. In the Patuxent and Potomac, the TN:TP ratios of external loads are 2-4 times higher than those observed over the previous two decades. These changes are attributed to point-source phosphorus controls and the likelihood that nitrogen-rich nonpoint source inputs, including contributions from the atmosphere, have increased. These higher N:P ratios now suggest a greater overall potential for phosphorus-limitation rather than nitrogen-limitation of phytoplankton in the areas studied. 66 refs., 6 figs., 7 tabs.

Magnien, R.E.; Summers, R.M. (Maryland Department of the Environment, Baltimore (United States)); Sellner, K.G. (Benedict Estuarine Research Lab., MD (United States))

1992-12-01

288

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

PubMed

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

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

2013-07-01

289

Response of algal metrics to nutrients and physical factors and identification of nutrient thresholds in agricultural streams  

USGS Publications Warehouse

Many streams within the United States are impaired due to nutrient enrichment, particularly in agricultural settings. The present study examines the response of benthic algal communities in agricultural and minimally disturbed sites from across the western United States to a suite of environmental factors, including nutrients, collected at multiple scales. The first objective was to identify the relative importance of nutrients, habitat and watershed features, and macroinvertebrate trophic structure to explain algal metrics derived from deposition and erosion habitats. The second objective was to determine if thresholds in total nitrogen (TN) and total phosphorus (TP) related to algal metrics could be identified and how these thresholds varied across metrics and habitats. Nutrient concentrations within the agricultural areas were elevated and greater than published threshold values. All algal metrics examined responded to nutrients as hypothesized. Although nutrients typically were the most important variables in explaining the variation in each of the algal metrics, environmental factors operating at multiple scales also were important. Calculated thresholds for TN or TP based on the algal metrics generated from samples collected from erosion and deposition habitats were not significantly different. Little variability in threshold values for each metric for TN and TP was observed. The consistency of the threshold values measured across multiple metrics and habitats suggest that the thresholds identified in this study are ecologically relevant. Additional work to characterize the relationship between algal metrics, physical and chemical features, and nuisance algal growth would be of benefit to the development of nutrient thresholds and criteria. ?? 2010 The Author(s).

Black, R.W.; Moran, P.W.; Frankforter, J.D.

2011-01-01

290

Nutrient load analysis of Lago de Yojoa, Honduras  

E-print Network

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 ...

Trate, Tia M. (Tia Marie)

2006-01-01

291

A Nutrient Combination that Can Affect Synapse Formation  

E-print Network

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 ...

Wurtman, Richard Jay

292

Herbivores and nutrients control grassland plant diversity via light limitation  

USGS Publications Warehouse

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.

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

293

Survey of States, Tribes, and Territories Nutrient Standards.  

National Technical Information Service (NTIS)

All States, Territories and Tribes were reviewed to determine if they have adopted nutrient criteria in their Water Quality Standards. Every State had narrative standards that protected the waters from objectionable conditions, such as floating material, ...

2003-01-01

294

Diet, nutrients, phytochemicals, and cancer metastasis suppressor genes  

E-print Network

Diet, nutrients, phytochemicals, and cancer metastasis suppressor genes Gary G. Meadows # Springer the mechanisms under- lying antimetastatic activity of some phytochemicals are being delineated, the impact of diet, dietary components, and various phytochemicals on metastasis suppressor genes is underexplored

Collins, Gary S.

295

Nutrient removal from swine lagoon effluent by duckweed  

SciTech Connect

Three duckweed geographic isolates were grown on varying concentrations of swine lagoon effluent in a greenhouse to determine their ability to remove nutrients from the effluent. Duckweed biomass was harvested every other day over a 12-day period. Duckweed biomass production, nutrient loss from the swine lagoon effluent, and nutrient content of duckweed biomass were used to identify effluent concentrations/geographic isolate combinations that are effective in terms of nutrient utilization from swine lagoon effluent and production of healthy duckweed biomass. When Lemna minor geographic isolate 8627 was grown on 50% swine lagoon effluent, respective losses of TKN, NH{sub 3}-N, TP, OPO{sub 4}-P, TOC, K, Cu, and Zn were 83, 100, 49, 31, 68, 21, 28 and 67%.

Bergmann, B.A.; Cheng, J.; Classen, J.; Stomp, A.M.

2000-04-01

296

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....

297

Intervertebral disc regeneration: do nutrients lead the way?  

PubMed

Strategies for the biological repair of intervertebral discs derive from the premise that disc degeneration results from impaired cellular activity and, therefore, that these structures can be induced to regenerate by implanting active cells or providing factors that restore normal cellular activity. In vitro and animal studies using this approach have had some success, but whether this success can be reproduced in degenerate human lumbar discs is unknown. Successful repair requires that the disc cells remain viable and active; they therefore need an adequate supply of nutrients. However, as the disc degenerates, the nutrient supply decreases, thereby limiting cell activity and viability. Current biologic approaches might place additional demands on an already precarious nutrient supply. Here, we discuss whether the loss of nutrients associated with disc degeneration limits the effectiveness of biologic approaches, and indicate that this neglected problem requires investigation if clinical application of such therapies is to succeed. PMID:24914695

Huang, Yong-Can; Urban, Jill P G; Luk, Keith D K

2014-09-01

298

Health Tip: Get the Right Nutrients While Nursing  

MedlinePLUS

... page, please enable JavaScript. Health Tip: Get the Right Nutrients While Nursing Beef up your diet for ... will do. HealthDay Copyright (c) 2014 HealthDay . All rights reserved. More Health News on: Breastfeeding Recent Health ...

299

Nutrient enrichment of the subarctic Pacific Ocean pycnocline  

NASA Astrophysics Data System (ADS)

At the end of the global thermohaline circulation, the subarctic Pacific is the richest nutrient repository in the world oceans. Trends towards lower oxygen and higher nutrients in waters below the surface layer (the pycnocline) have been observed in recent decades. We assess these trends using data from four programs and suggest the enrichment of pycnocline nitrate (200 Gmol y-1) is essential in keeping supply to the surface ocean constant, despite increasing upper ocean stratification. A nitrate budget helps identify possible vertical processes that could account for nutrient redistribution. We hypothesize that warming and oxygen loss in the deeper pycnocline, arising from ice loss in the Okhotsk Sea, have initiated a largely vertical redistribution of nutrients due to compression of vertical migrator habitat and/or changes in dissolution of sinking particulates. Coupled climate-ecosystem models will need to incorporate these processes to more fully understand projected changes in the subarctic Pacific.

Whitney, Frank A.; Bograd, Steven J.; Ono, Tsuneo

2013-05-01

300

Wild and commercial mushrooms as source of nutrients and nutraceuticals  

Microsoft Academic Search

In order to promote the use of mushrooms as source of nutrients and nutraceuticals, several experiments were performed in wild and commercial species. The analysis of nutrients included determination of proteins, fats, ash, and carbohydrates, particularly sugars by HPLC-RI. The analysis of nutraceuticals included determination of fatty acids by GC-FID, and other phytochemicals such as tocopherols, by HPLC-fluorescence, and phenolics,

Lillian Barros; Telma Cruz; Paula Baptista; Letícia M. Estevinho; Isabel C. F. R. Ferreira

2008-01-01

301

Nutrient Transport into the White Sea with River Runoff  

Microsoft Academic Search

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,

A. V. Leonov; O. V. Chicherina

2004-01-01

302

Soil nutrient leaching in response to simulated acid rain treatment  

Microsoft Academic Search

Soil and soil solution nutrient concentrations were evaluated over a 30-mo period to determine the impact of simulated acidic precipitation (70:30 equivalent basis H2SO4: HNO3) at pH values of 5.7, 4.5, 4.0, and 3.5 on forest. microcosms. Soil nutrient analysis indicated significantly lower concentrations of exchangeable Ca and Mg in the top 3.5 cm of the mineral soil after 30

J. M. Kelly; R. C. Strickland

1987-01-01

303

Nutrient addition accelerates leaf breakdown in an alpine springbrook  

Microsoft Academic Search

This study assessed the effect of nutrient enrichment on organic matter breakdown in an alpine springbrook, using alder leaf\\u000a packs to which phosphorus and nitrogen were added in the form of slow-release fertilizer briquettes. The breakdown of leaf\\u000a packs with nutrients added (k=0.0284 day–1) was significantly faster than that of unfertilized packs (k=0.0137 day–1), resulting in a 30% higher mass

Christopher T. Robinson; Mark O. Gessner

2000-01-01

304

Inventory of nutrient compounds in the Yellow Sea  

Microsoft Academic Search

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

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

2003-01-01

305

Dietary Sources of Nutrients among US Adults, 1989 to 1991  

Microsoft Academic Search

Objective To identify major food sources of 27 nutrients and dietary constituents for US adults.Design Single 24-hour dietary recalls were used to assess intakes. From 3,970 individual foods reported, 112 groups were created on the basis of similarities in nutrient content or use. Food mixtures were disaggregated using the US Department of Agriculture (USDA) food grouping system.Subjects\\/setting A nationally representative

AMY F SUBAR; SUSAN M KREBS-SMITH; ANNETTA COOK; LISA L KAHLE

1998-01-01

306

Interactive Effects of Nutrient and Mechanical Stresses on Plant Morphology  

PubMed Central

Background and Aims Plant species frequently encounter multiple stresses under natural conditions, and the way they cope with these stresses is a major determinant of their ecological breadth. The way mechanical (e.g. wind, current) and resource stresses act simultaneously on plant morphological traits has been poorly addressed, even if both stresses often interact. This paper aims to assess whether hydraulic stress affects plant morphology in the same way at different nutrient levels. Methods An examination was made of morphological variations of an aquatic plant species growing under four hydraulic stress (flow velocity) gradients located in four habitats distributed along a nutrient gradient. Morphological traits covering plant size, dry mass allocation, organ water content and foliage architecture were measured. Key Results Significant interactive effects of flow velocity and nutrient level were observed for all morphological traits. In particular, increased flow velocity resulted in size reductions under low nutrient conditions, suggesting an adaptive response to flow stress (escape strategy). On the other hand, moderate increases in flow velocity resulted in increased size under high nutrient conditions, possibly related to an inevitable growth response to a higher nutrient supply induced by water renewal at the plant surface. For some traits (e.g. dry mass allocation), a consistent sense of variation as a result of increasing flow velocity was observed, but the amount of variation was either reduced or amplified under nutrient-rich compared with nutrient-poor conditions, depending on the traits considered. Conclusions These results suggest that, for a given species, a stress factor may result, in contrasting patterns and hence strategies, depending on a second stress factor. Such results emphasize the relevance of studies on plant responses to multiple stresses for understanding the actual ecological breadth of species. PMID:17913725

Puijalon, Sara; Lena, Jean-Paul; Bornette, Gudrun

2007-01-01

307

Selection of Optimal Auxiliary Soil Nutrient Variables for Cokriging Interpolation  

PubMed Central

In order to explore the selection of the best auxiliary variables (BAVs) when using the Cokriging method for soil attribute interpolation, this paper investigated the selection of BAVs from terrain parameters, soil trace elements, and soil nutrient attributes when applying Cokriging interpolation to soil nutrients (organic matter, total N, available P, and available K). In total, 670 soil samples were collected in Fuyang, and the nutrient and trace element attributes of the soil samples were determined. Based on the spatial autocorrelation of soil attributes, the Digital Elevation Model (DEM) data for Fuyang was combined to explore the coordinate relationship among terrain parameters, trace elements, and soil nutrient attributes. Variables with a high correlation to soil nutrient attributes were selected as BAVs for Cokriging interpolation of soil nutrients, and variables with poor correlation were selected as poor auxiliary variables (PAVs). The results of Cokriging interpolations using BAVs and PAVs were then compared. The results indicated that Cokriging interpolation with BAVs yielded more accurate results than Cokriging interpolation with PAVs (the mean absolute error of BAV interpolation results for organic matter, total N, available P, and available K were 0.020, 0.002, 7.616, and 12.4702, respectively, and the mean absolute error of PAV interpolation results were 0.052, 0.037, 15.619, and 0.037, respectively). The results indicated that Cokriging interpolation with BAVs can significantly improve the accuracy of Cokriging interpolation for soil nutrient attributes. This study provides meaningful guidance and reference for the selection of auxiliary parameters for the application of Cokriging interpolation to soil nutrient attributes. PMID:24927129

Song, Genxin; Zhang, Jing; Wang, Ke

2014-01-01

308

Swift recovery of Sphagnum nutrient concentrations after excess supply  

PubMed Central

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

Heijmans, Monique M. P. D.

2008-01-01

309

Nutrition and the developing brain: nutrient priorities and measurement.  

PubMed

Nutrients and growth factors regulate brain development during fetal and early postnatal life. The rapidly developing brain is more vulnerable to nutrient insufficiency yet also demonstrates its greatest degree of plasticity. Certain nutrients have greater effects on brain development than do others. These include protein, energy, certain fats, iron, zinc, copper, iodine, selenium, vitamin A, choline, and folate. The effect of any nutrient deficiency or overabundance on brain development will be governed by the principle of timing, dose, and duration. The ability to detect the specific effects of nutrient deficiencies is dependent on knowing which area of the brain is preferentially affected and on having neurologic assessments that tap into the functions of those specific areas. As examples, protein-energy malnutrition causes both global deficits, which are testable by general developmental testing, and area-specific effects on the hippocampus and the cortex. Iron deficiency alters myelination, monoamine neurotransmitter synthesis, and hippocampal energy metabolism in the neonatal period. Assessments of these effects could include tests for speed of processing (myelination), changes in motor and affect (monoamines), and recognition memory (hippocampus). Zinc deficiency alters autonomic nervous system regulation and hippocampal and cerebellar development. Long-chain polyunsaturated fatty acids are important for synaptogenesis, membrane function, and, potentially, myelination. Overall, circuit-specific behavioral and neuroimaging tests are being developed for use in progressively younger infants to more accurately assess the effect of nutrient deficits both while the subject is deficient and after recovery from the deficiency. PMID:17284765

Georgieff, Michael K

2007-02-01

310

Characterization of Pseudomonas putida Genes Responsive to Nutrient Limitation  

SciTech Connect

The low bioavailability of nutrients and oxygen in the soil environment has hampered successful expression of biodegradation/biocontrol genes that are driven by promoters highly active during routine laboratory conditions of high nutrient- and oxygen-availability. Hence, in the present study, expression of the gus-tagged genes in 12 Tn5-gus mutants of the soil microbe Pseudomonas putida PNL-MK25 was examined under various conditions chosen to mimic the soil environment: low carbon, phosphate, nitrate, or oxygen, and in the rhizosphere. Based on their expression profiles, three nutrient-responsive mutant (NRM) strains, NRM5, NRM7, and NRM17, were selected for identification of the tagged genes. In the mutant strain NRM5, expression of the glutamate dehydrogenase (gdhA) gene was increased between 4.9- to 26.4-fold under various low nutrient conditions. In NRM7, expression of the novel NADPH:quinone oxidoreductase-like (nql) gene was consistently amongst the highest and was synergistically upregulated by low nutrient and anoxic conditions. The cyoD gene in NRM17, which encodes the fourth subunit of the cytochrome o ubiquinol oxidase complex, had decreased expression in low nutrient conditions but its absolute expression levels was still amongst the highest. Additionally, it was independent of oxygen availability, in contrast to that in E. coli.

Syn, Chris K.; Magnuson, Jon K.; Kingsley, Mark T.; Swarup, Sanjay

2004-06-01

311

Status of selected nutrients in obese dogs undergoing caloric restriction  

PubMed Central

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

2013-01-01

312

Oxygen consumption rates of bacteria under nutrient-limited conditions.  

PubMed

Many environments on Earth experience nutrient limitation and as a result have nongrowing or very slowly growing bacterial populations. To better understand bacterial respiration under environmentally relevant conditions, the effect of nutrient limitation on respiration rates of heterotrophic bacteria was measured. The oxygen consumption and population density of batch cultures of Escherichia coli K-12, Shewanella oneidensis MR-1, and Marinobacter aquaeolei VT8 were tracked for up to 200 days. The oxygen consumption per CFU (QO2) declined by more than 2 orders of magnitude for all three strains as they transitioned from nutrient-abundant log-phase growth to the nutrient-limited early stationary phase. The large reduction in QO2 from growth to stationary phase suggests that nutrient availability is an important factor in considering environmental respiration rates. Following the death phase, during the long-term stationary phase (LTSP), QO2 values of the surviving population increased with time and more cells were respiring than formed colonies. Within the respiring population, a subpopulation of highly respiring cells increased in abundance with time. Apparently, as cells enter LTSP, there is a viable but not culturable population whose bulk community and per cell respiration rates are dynamic. This result has a bearing on how minimal energy requirements are met, especially in nutrient-limited environments. The minimal QO2 rates support the extension of Kleiber's law to the mass of a bacterium (100-fg range). PMID:23770901

Riedel, Timothy E; Berelson, William M; Nealson, Kenneth H; Finkel, Steven E

2013-08-01

313

Long-term nutrient enrichment decouples predator and prey production  

PubMed Central

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

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

2009-01-01

314

Nutrient density of beverages in relation to climate impact  

PubMed Central

The food chain contributes to a substantial part of greenhouse gas (GHG) emissions and growing evidence points to the urgent need to reduce GHGs emissions worldwide. Among suggestions were proposals to alter food consumption patterns by replacing animal foods with more plant-based foods. However, the nutritional dimensions of changing consumption patterns to lower GHG emissions still remains relatively unexplored. This study is the first to estimate the composite nutrient density, expressed as percentage of Nordic Nutrition Recommendations (NNR) for 21 essential nutrients, in relation to cost in GHG emissions of the production from a life cycle perspective, expressed in grams of CO2-equivalents, using an index called the Nutrient Density to Climate Impact (NDCI) index. The NDCI index was calculated for milk, soft drink, orange juice, beer, wine, bottled carbonated water, soy drink, and oat drink. Due to low-nutrient density, the NDCI index was 0 for carbonated water, soft drink, and beer and below 0.1 for red wine and oat drink. The NDCI index was similar for orange juice (0.28) and soy drink (0.25). Due to a very high-nutrient density, the NDCI index for milk was substantially higher (0.54) than for the other beverages. Future discussion on how changes in food consumption patterns might help avert climate change need to take both GHG emission and nutrient density of foods and beverages into account. PMID:20806074

Smedman, Annika; Lindmark-Mansson, Helena; Drewnowski, Adam; Edman, Anna-Karin Modin

2010-01-01

315

Potato growth and yield using nutrient film technique (NFT)  

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

316

Insights into digestion and absorption of major nutrients in humans  

NSDL National Science Digital Library

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.

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

2010-06-01

317

Response to fertilization by various plant growth forms in an Alaskan tundra: nutrient accumulation and growth  

SciTech Connect

The fertilization responses of six tundra species belonging to three plant growth forms were compared to test the hypothesis that species of the same plant growth form are more similar to one another than to other growth forms in their response to a controlled perturbation. The controlled perturbation was a complete factorial NPK fertilization experiment in tussock tundra at Eagle Creek, Alaska, USA. We compared deciduous shrubs, evergreen shrubs, and functionally deciduous graminoids in terms of mineral and total nonstructural carbohydrate (TNC) concentrations, and annual production per stem or tiller.

Shaver, G.R. (San Diego State Univ., CA); Chapin, F.S. III

1980-06-01

318

Response of algal metrics to nutrients and physical factors and identification of nutrient thresholds in agricultural streams  

Microsoft Academic Search

Many streams within the United States are impaired due to nutrient enrichment, particularly in agricultural settings. The\\u000a present study examines the response of benthic algal communities in agricultural and minimally disturbed sites from across\\u000a the western United States to a suite of environmental factors, including nutrients, collected at multiple scales. The first\\u000a objective was to identify the relative importance of

Robert W. Black; Patrick W. Moran; Jill D. Frankforter

2011-01-01

319

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

PubMed Central

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

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

2013-01-01

320

Impact of the Invasive Alien Plant Solidago Gigantea on Primary Productivity, Plant Nutrient Content and Soil Mineral Nutrient Concentrations  

Microsoft Academic Search

Invasion by alien plants can alter ecosystem processes and soil properties. In this study, we compared aboveground productivity, nutrient pools in standing biomass and topsoil (0–0.10 m) mineral nutrient concentrations between plots invaded by Early Goldenrod (Solidago gigantea) and adjacent, uninvaded, vegetation at five sites in Belgium. The five sites were characterised by a resident perennial herbaceous vegetation and spanned a wide

Sonia Vanderhoeven; Nicolas Dassonville; Lydie Chapuis-Lardy; Matthieu Hayez; Pierre Meerts

2006-01-01

321

Hydromorphological control of nutrient cycling in complex river floodplain systems  

NASA Astrophysics Data System (ADS)

Riparian zones and floodplains are key components within river ecosystems controlling nutrient cycling by promoting transformation processes and thus, act as biogeochemical hot spots. The intensity of these processes depends on the exchange conditions (the connectivity) with the main channel and the morphological setting of the water bodies. At the landscape scale, three interrelated principles of hydromorphological dynamics can be formulated regarding the cycling and transfer of carbon and nutrients in large rivers ecosystems: a) The mode of carbon and nutrient delivery affects ecosystem functioning; b) Increasing residence time and contact area impact nutrient transformation; c) Floods and droughts are natural events that strongly influence pathways of carbon and nutrient cycling. These three principles of hydromorphological dynamics control the nutrient uptake and retention and are linked over different temporal and spatial scales. All three factors can be strongly affected by natural disturbances or anthropogenic impacts, through a change in either the water regime or the geomorphologic setting of the river valley. Any change in natural water regimes will affect the biogeochemistry of riparian zones and floodplains as well as their ability to cycle and mitigate nutrient fluxes originating from upstream and/or upslope. Especially these areas have been altered by river regulation and land use changes over the last 200 years leading to the deterioration of the functioning of these compartments within the riverine landscape. The resulting deficits have prompted rehabilitation and restoration measures aiming to increase the spatial heterogeneity, the complexity, of these ecosystems. Yet, a more integrated approach is needed considering the present status of nutrient dynamics and the effects of restoration measures at different scales. The present paper analyses the effects of river side-arm restoration on ecosystem functions within the side-arm and highlights potential effects on the main channel in a large river, the Danube River. During the growing season of 2006 and the end of the growing season 2007, a large-scale field survey was completed for two areas in the floodplain stretch of the Danube River one of which has recently undergone restoration via reconnection to the Danube River main channel. The sampling compared the sediment nutrient concentrations and potential denitrification and respiration rates. With changing surface water connection to the Danube River, the water bodies in the two compared floodplains experienced different patterns of microbial processing rates, particularly potential denitrification. We demonstrate that principles of hydromorphological dynamics control nutrient cycling in the water column and at the water sediment interface. These findings confirm the environmental control on these processes and their potential use as proxies to assess the consequences of hydrological changes by restoration measures on river ecosystem functioning.

Hein, T.; Bondar-Kunze, E.; Felkl, M.; Habersack, H.; Mair, M.; Pinay, G.; Tritthart, M.; Welti, N.

2009-04-01

322

TOR complex 2 (TORC2) in Dictyostelium suppresses phagocytic nutrient capture independently of TORC1-mediated nutrient sensing  

PubMed Central

The TOR protein kinase functions in two distinct complexes, TOR complex 1 (TORC1) and 2 (TORC2). TORC1 is required for growth in response to growth factors, nutrients and the cellular energy state; TORC2 regulates AKT signaling, which can modulate cytoskeletal polarization. In its ecological niche, Dictyostelium engulf bacteria and yeast for nutrient capture. Despite the essential role of TORC1 in control of cellular growth, we show that nutrient particle capture (phagocytosis) in Dictyostelium is independent of TORC1-mediated nutrient sensing and growth regulation. However, loss of Dictyostelium TORC2 components Rictor/Pia, SIN1/RIP3 and Lst8 promotes nutrient particle uptake; inactivation of TORC2 leads to increased efficiency and speed of phagocytosis. In contrast to phagocytosis, we show that macropinocytosis, an AKT-dependent process for cellular uptake of fluid phase nutrients, is not regulated by either of the TOR complexes. The integrated and balanced regulation of TORC1 and TORC2 might be crucial in Dictyostelium to coordinate growth and energy needs with other essential TOR-regulated processes. PMID:22266904

Rosel, Daniel; Khurana, Taruna; Majithia, Amit; Huang, Xiuli; Bhandari, Ramanath; Kimmel, Alan R.

2012-01-01

323

Species Diversity Across Nutrient Gradients: An Analysis of Resource Competition in Model Ecosystems  

Microsoft Academic Search

The capture and efficient use of limiting resources influence the competitive success of individual plant species as well as species diversity across resource gradients. In simulations, efficient nutrient acquisition or nutrient retention by species were key predictors of success when nutrients were limiting. Increased nutrient supply favored species with characteristics that improved light interception or light use. Ecological theory suggests

Darrell A. Herbert; Edward B. Rastetter; Laura Gough; Gaius R. Shaver

2004-01-01

324

Loblolly pine growth and soil nutrient stocks eight years after forest slash incorporation  

Microsoft Academic Search

Incorporation of forest slash during stand establishment is proposed as a means of increasing soil carbon and nutrient stocks. If effective, the increased soil carbon and nutrient status may result in increased aboveground tree growth. Eight years after study installation, the impact of forest slash incorporation into the soil on soil carbon and nutrient stocks, foliar nutrients and loblolly pine

Felipe G. Sanchez; Emily A. Carter; Zakiya H. Leggett

2009-01-01

325

The Effects of Deforestation on Nutrient Concentrations in Tributaries of Lake Tanganyika  

Microsoft Academic Search

Deforestation has many significant ecological consequences. The removal of vegetation results in increased erosion of soil sediments, which are many times deposited in water bodies, consequently depositing soil particles and nutrients. A decrease in vegetation also corresponds with a decrease in nutrient uptake in the soil, resulting in an increased rate of nutrient leaching from the soil. The leached nutrients

Catherine O'reilly

326

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

Microsoft Academic Search

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

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

2001-01-01

327

Pennsylvania Act 38/Nutrient Management Program/Technical Manual January 2013  

E-print Network

that is required to implement the nutrient management plan for this operation. The information generatedPennsylvania Act 38/Nutrient Management Program/Technical Manual January 2013 NMP Summary ­ Page 1 Nutrient Management Plan Summary The Nutrient Management Plan Summary is comprised of four components

Guiltinan, Mark

328

Pennsylvania Act 38/Nutrient Management Program/Technical Manual January 2014  

E-print Network

& Responsibilities Additional Nutrient Management Plan Requirements Operator Management Map Table of Contents PagePennsylvania Act 38/Nutrient Management Program/Technical Manual January 2014 Supplement 2 Sample Nutrient Management Plan Supplement 2 Sample Nutrient Management Plan Supplement 2 provides a sample

Guiltinan, Mark

329

Pennsylvania Act 38/Nutrient Management Program/Technical Manual January 2014  

E-print Network

that is required to implement the nutrient management plan for this operation. The information generatedPennsylvania Act 38/Nutrient Management Program/Technical Manual January 2014 NMP Summary ­ Page 1 Nutrient Management Plan Summary The Nutrient Management Plan Summary is comprised of four components

Guiltinan, Mark

330

The Influence of Microtopography on Soil Nutrients in Created Mitigation Wetlands  

E-print Network

and physicochemistry, thus affecting the balance of plant nutrients in soil. Wet- land plants vary in nutrient demandsThe Influence of Microtopography on Soil Nutrients in Created Mitigation Wetlands Kurt F. Moser,1- graphy and soil nutrients (and trace elements), comparing results for created and reference wetlands

331

Watershed Classification as a Tool to Partition Variance in Nutrient Biological Response Relationships  

Microsoft Academic Search

Refining effects-based nutrient water quality criteria requires the partitioning of variation in nutrient-response relationships, including responses related to algae and dissolved oxygen, among stream types. In addition to nutrients, algal accrual rate can be limited by shading, herbivory, and the instream flow regime. For example, moderate flow rates can stimulate nutrient uptake, while frequent spates can scour algal biomass. Furthermore,

N. E. Detenbeck; S. Yue; J. A. Thompson; D. Pfeifer; C. R. Bauer

2005-01-01

332

Reducing future nutrient inputs to the Black Sea.  

PubMed

Rivers export increasing amounts of dissolved inorganic (DIN, DIP) and organic (DON, DOP) nitrogen and phosphorus to the Black Sea causing coastal eutrophication. The aim of this study is to explore future trends in river export of these nutrients to the sea through a sensitivity analysis. We used the Global NEWS (Nutrient Export from WaterSheds) model to this end. We calculated that between 2000 and 2050 nutrient inputs to the Black Sea may increase or decrease, depending on the assumed environmental management. We analyzed the effects of agricultural and sewage management on nutrient inputs to the sea in 2050 relative to two Millennium Ecosystem Assessment (MEA) scenarios, Global Orchestration (GO) and Adaptive Mosaic (AM). In these baselines, total N and P inputs to the Black Sea decrease between 2000 and 2050, but not for all rivers and nutrient forms. Our results indicate that it is possible to reduce nutrient inputs to the sea further between 2000 and 2050 in particular for dissolved inorganic N and P and for many river basins, but not for all. For scenarios assuming combined agricultural and sewage management dissolved inorganic N and P inputs to the Black Sea are reduced by up to two-thirds between 2000 and 2050 and dissolved organic N and P inputs by one-third. River export of DIN is mainly affected by agricultural management and that of DIP by sewage management. On the other hand, in scenarios assuming increased fertilizer use for, for instance bioenergy crops, nutrient inputs to the sea increase. An increase in DIP inputs by southern rivers seems difficult to avoid because of the increasing number of people connected to sewage systems. PMID:23906857

Strokal, Maryna Petrivna; Kroeze, Carolien; Kopilevych, Volodymyr Abramovych; Voytenko, Larysa Vladyslavivna

2014-01-01

333

Sleep symptoms associated with intake of specific dietary nutrients.  

PubMed

Sleep symptoms are associated with weight gain and cardiometabolic disease. The potential role of diet has been largely unexplored. Data from the 2007-2008 National Health and Nutrition Examination Survey (NHANES) were used (n = 4552) to determine which nutrients were associated with sleep symptoms in a nationally representative sample. Survey items assessed difficulty falling asleep, sleep maintenance difficulties, non-restorative sleep and daytime sleepiness. Analyses were adjusted for energy intake, other dietary factors, exercise, body mass index (BMI) and sociodemographics. Population-weighted, logistic regression, with backwards-stepwise selection, examined which nutrients were associated with sleep symptoms. Odds ratios (ORs) reflect the difference in odds of sleep symptoms associated with a doubling in nutrient. Nutrients that were associated independently with difficulty falling asleep included (in order): alpha-carotene (OR = 0.96), selenium (OR = 0.80), dodecanoic acid (OR = 0.91), calcium (OR = 0.83) and hexadecanoic acid (OR = 1.10). Nutrients that were associated independently with sleep maintenance difficulties included: salt (OR = 1.19), butanoic acid (0.81), carbohydrate (OR = 0.71), dodecanoic acid (OR = 0.90), vitamin D (OR = 0.84), lycopene (OR = 0.98), hexanoic acid (OR = 1.25) and moisture (OR = 1.27). Nutrients that were associated independently with non-restorative sleep included butanoic acid (OR = 1.09), calcium (OR = 0.81), vitamin C (OR = 0.92), water (OR = 0.98), moisture (OR = 1.41) and cholesterol (OR = 1.10). Nutrients that were associated independently with sleepiness included: moisture (OR = 1.20), theobromine (OR = 1.04), potassium (OR = 0.70) and water (OR = 0.97). These results suggest novel associations between sleep symptoms and diet/metabolism, potentially explaining associations between sleep and cardiometabolic diseases. PMID:23992533

Grandner, Michael A; Jackson, Nicholas; Gerstner, Jason R; Knutson, Kristen L

2014-02-01

334

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...

335

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

Microsoft Academic Search

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

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

2011-01-01

336

Nutrient Overland Flow and Nitrous Oxide Losses from Residential Landscapes  

NASA Astrophysics Data System (ADS)

Residential lawn maintenance practices (mowing, fertilizer, irrigation, reseeding, and aeration) result in aesthetically appealing landscapes, but is capable of causing nutrient losses via overland flow or gaseous losses to the atmosphere (e.g. nitrous oxide - N2O). The overall study objective was to determine the effect of lawn maintenance on nutrient losses from residential landscapes. The specific objectives were: modify a passive sampling system to determine nutrient loads due to overland flow from lawns; evaluate differences in overland flow frequency, volumes, and nutrient losses during rainfall events (? 25.4 mm); and compare N2O losses following rainfall events. Three distinct lawn schemes were studied: a high maintenance fescue (Festuca arundinacea) lawn (HMFL), a low maintenance fescue lawn (LMFL), and a mixed forested residential landscape (FRL). The modified passive sampling system allowed 100% recovery of overland flow and demonstrated that differences in maintenance influenced the overland flow frequency, volumes, and nutrient losses. The LMFL had the greatest overland flow volumes and nutrient unit area loads; although N and P concentrations in overland flow exceeded USEPA recommendations from all three lawns. Nutrient losses (g ha-1 yr-1) from all three residential landscapes were 1000 times less than fertilizer (kg ha-1 yr-1) and throughfall (kg ha-1 yr-1) inputs, partially due to the presence of well-structured soils (low bulk densities and high infiltration rates). Irrigation practices between the HMFL and LMFL explained the differences in overland flow volumes and nutrient loads, especially during the first half of the study when drought conditions existed at the study site (Cary, North Carolina). The lack of irrigation in the LMFL resulted in early dormancy and a minimal thatch layer and lower plant density, which caused higher volumes of overland flow. Trends in the N2O losses from the HMFL and LMFL were associated with timing of fertilizer applications, presence or absence of irrigation, and seasonal growth patterns of the fescue. For the RFL, the presence of a decomposing litter layer limited N2O production. Well-maintained residential lawns, receiving recommended fertilizer N applications and frequent irrigation, reduce nutrient losses via overland flow but may provide optimum conditions for greater N2O fluxes.

Osmond, D.; Spence, P.; Heitman, J.; Robarge, W. P.; Walker, J. T.; water quality, nitrogen emissions, residential landscapes

2011-12-01

337

Critical source times for nutrient loss in agricultural catchment streams  

NASA Astrophysics Data System (ADS)

Identifying periods of the year when there is a high risk of incidental nutrient loss from farms via runoff to streams underpins current nutrient management legislation in Europe. This research explored high-temporal resolution nutrient transfer patterns relative to the time that manure and fertiliser are prohibited from being spread (the mandatory spreading 'closed' period) in five Irish agricultural catchments. Catchment nutrient losses during the 12 week closed periods in 2009-10, 2010-11 and 2011-12 were compared with losses during the remainder of the year, and with losses in the two week 'shoulder' periods immediately before and after the closed period. The closed period losses were assumed to be residual from soil nutrient stores and the 'shoulder' periods were considered to also include incidental losses. Nutrient loss was measured at sub-hourly frequency as total phosphorus (P) and total oxidised nitrogen (mostly nitrate-N) fluxes in streamflow. The streamflow fluxes showed that the proportion of the annual nitrate-N loss occurring during the closed periods (33-61%) was high compared with the remainder of the year. Six to ten times more nitrate-N loss occurred in the two weeks after, compared with the two weeks before, the closed period. These two week 'shoulder' period losses were, on average, less than or equal to 2.5 kg nitrate-N/ha and 9% of total annual nitrate-N loss in streamflow. On average, 40-53% of the annual P loss occurred during the closed periods but in a runoff-prone catchment in a year with a wet summer, the closed period was the less risky period. Similar to nitrate-N, two to twenty times more P loss occurred in the two weeks after, compared with the two weeks before, the closed period. These shoulder period losses were, on average, less than or equal to 0.027 kg/ha and 4.2% of total annual P loss in streamflow. The proportion of the shoulder period loss that could be attributed to recently spread nutrients was not known but can be informed by farm practice and nutrient flow pathways analysis. Losses after the closed period, especially P, could include a significant contribution from eroded soil, which would not be prevented by extending the spreading closed period. Policy proposals to extend the mandatory closed period should consider the long term potential for nutrient runoff and plant growth conditions during the 'shoulder' periods, infrastructure costs of further storage requirements, production costs of restricting critical farm operations during the shoulders and unintended environmental costs such as shifting farm activities towards periods when water bodies are more susceptible to eutrophication.

Melland, Alice; Shore, Mairead; Mellander, Per-Erik; McDonald, Noeleen; Shortle, Ger; Murphy, Paul; Jordan, Phil

2014-05-01

338

Using criteria to establish nutrient intake values (NIVs).  

PubMed

One of the most important of the nutrient intake values (NIVs) is the average nutrient requirement (ANR). The ANR is defined as an intake value that will be adequate for half of the individuals in a group of people with similar characteristics. It is used to estimate the prevalence of adequacy, and it serves as the basis for the individual nutrient level (INLx). The determination of adequacy is a complex process, with the resulting value of the ANR dependent on the criterion or functional outcome chosen to define nutrient adequacy. Because nutrients have multiple sites of action in human metabolism, it is possible to demonstrate abnormal function in one parameter measured or observed as a result of inadequate intake of a nutrient, while other parameters requiring the same nutrient appear normal or within normal ranges. Thus, depending on the criterion of adequacy selected, the requirement for a given nutrient may be at a lower or a higher intake amount. In harmonizing development of NIVs, it is important to clearly identify the criterion of adequacy selected and the rationale for its selection. Rarely are available data sufficient to provide dose-response information from which to select a level of intake at which half of the individuals demonstrate adequacy and half appear to demonstrate inadequacy. Three levels of intake, of which at least one level of intake is below the requirement for most of the individuals in the sample, and one level of intake is above their requirement, are useful for establishing a level at which half of the group might be considered to demonstrate adequacy. Types of human nutrient studies that may be used to obtain data are discussed, as well as characteristics of the sample size needed to demonstrate adequacy. The variation in requirements is also an important aspect in predicting levels of intake that will have defined probabilities of adequacy for groups (to develop the INLx where x is the defined probability chosen). An analysis of the origins of different types of variability is presented. When estimating energy requirements, a special case of NIVs, important issues must be considered. Additionally, an example of evaluating data used to establish an ANR for vitamin A, and the effect of variability in requirements for vitamin A, is provided. PMID:17521118

Yates, Allison A

2007-03-01

339

Insect herbivory accelerates nutrient cycling and increases plant production  

PubMed Central

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

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

2000-01-01

340

Circulation and nutrient modeling of Thermaikos Gulf, Greece  

NASA Astrophysics Data System (ADS)

Thermaikos Gulf is considered to be one of the most polluted coastal zones in Greece. It is the final receptor of both municipal and industrial wastewaters from the city of Thessaloniki and of two heavily polluted rivers, Axios and Aliakmon. Nutrient enrichment and consequent eutrophication is the primary water quality issue of Thermaikos. The mathematical model WASP 6.0 was used to simulate the hydrodynamics, nutrient dynamics and phytoplakton evolution in the gulf. The model is a physical-based model that compartmentalizes the water body into high dispersivity, uniform concentration compartments. It then performs mass balances on water quantity and quality. In addition to the hydrodynamics, the model can simulate the carbon, oxygen, nitrogen, phosphorous and plankton concentrations in the water body. Monthly hydrologic and water quality fluxes from 1997 to 1998, inputs to the gulf and seasonal nutrient surveys in the gulf were used to calibrate nutrient dynamics. The gulf was compartmentalized into 12 compartments, six were horizontal and two were vertical. Salinity data were used to calibrate the hydrodynamic variables of the model. Model calibration was conducted by minimizing the root mean square error between field observations and model simulation. The model was able to capture the variation of salinity and nutrient concentrations. The results showed the importance of Thessaloniki effluents to the Thessaloniki Bay and Gulf and the Axios and Aliakmon River loads to the degree of eutrophication of the entire gulf. The model can be used to assess management scenarios to improve the water quality of the gulf.

Nikolaidis, Nikolaos P.; Karageorgis, Aristomenis P.; Kapsimalis, Vasilios; Marconis, Giannis; Drakopoulou, Paraskevi; Kontoyiannis, Harilaos; Krasakopoulou, Evangelia; Pavlidou, Alexandra; Pagou, Kalliopi

2006-04-01

341

The imprint of crop choice on global nutrient needs  

NASA Astrophysics Data System (ADS)

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.

Jobbágy, Esteban G.; Sala, Osvaldo E.

2014-08-01

342

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

PubMed

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

Zhu, Yu-Mei; Liu, Su-Mei

2011-09-01

343

Effects of salinity and nutrient addition on mangrove Excoecaria agallocha.  

PubMed

Effects of salinity on seed germination and growth of young (1 month old) and old (2-year old) seedlings of Excoecaria agallocha were investigated. Combined effects of salinity and nutrient level were also examined on old seedlings. Seed germination was best at 0 and 5 psu salinity. 15 psu salinity significantly delayed root initiation and decreased final establishment rate. All seeds failed to establish at 25 psu salinity. Young seedlings performed best at 0 and 5 psu, but growth was stunned at 15 psu, and all seedlings died within 90 days at 25 psu. Old seedlings grew best at salinities below 5 psu and they survived the whole cultivation at 25 psu. This indicated that E. agallocha increased salt tolerance over time. Gas exchange was significantly compromised by salinities above 15 psu but evidently promoted by high nutrient. Proline accumulated considerably at high nutrient, and its contents increased from 0 to 15 psu but decreased at 25 psu salinity. Lipid peroxidation was aggravated by increasing salinity beyond 15 psu but markedly alleviated by nutrient addition. These responses indicated that E. agallocha was intolerant to high salinity but it can be greatly enhanced by nutrient addition. PMID:24691495

Chen, Yaping; Ye, Yong

2014-01-01

344

Modelling macrofaunal biomass in relation to hypoxia and nutrient loading  

NASA Astrophysics Data System (ADS)

Nutrient loading of aquatic ecosystems results in more food for benthic macrofaunal communities but also increases the risk of hypoxia, resulting in a reduction or complete loss of benthic biomass. This study investigates the interaction between eutrophication, hypoxia and benthic biomass with emphasis on the balance between gains and loss of benthic biomass due to changes in nutrient loadings. A physiological fauna model with 5 functional groups was linked to a 3D coupled hydrodynamic-ecological Baltic Sea model. Model results revealed that benthic biomass increased between 0 and 700% after re-oxygenating bottom waters. Nutrient reduction scenarios indicated improved oxygen concentrations in bottom waters and decreased sedimentation of organic matter up to 40% after a nutrient load reduction following the Baltic Sea Action Plan. The lower food supply to benthos reduced the macrofaunal biomass up to 35% especially in areas not currently affected by hypoxia, whereas benthic biomass increased up to 200% in areas affected by eutrophication-induced hypoxia. The expected changes in benthic biomass resulting from nutrient load reductions and subsequent reduced hypoxia may not only increase the food supply for benthivorous fish, but also significantly affect the biogeochemical functioning of the ecosystem.

Timmermann, Karen; Norkko, Joanna; Janas, Urszula; Norkko, Alf; Gustafsson, Bo G.; Bonsdorff, Erik

2012-12-01

345

Dietary sources of nutrient consumption in a rural Japanese population.  

PubMed

We determined the sources of nutrient intake of 59 men and 60 women in two rural towns in the Miyagi Prefecture, a northeastern part of Japan. Four 3-day food records were collected in four seasons within a year. The total dishes and recipes were classified into 197 items. Their percent contributions to the total population consumption of energy and 14 nutrients were calculated as the sum of the nutrient intake contributed by a given dish or recipe divided by the total nutrient intake from all the items. Rice was the largest contributor for energy (29.8%), protein (13.0%) and carbohydrates (45.3%). Miso soup, as a dish, was a leading contributor (7.1%) for fat. The largest contributor for sodium, calcium, carotene, vitamin C were miso soup (17.1%), milk (16.6%), spinach (23.6%), green tea (13.6%), respectively. The result suggests that the examination of nutrient sources based on dishes and recipes, rather than on food materials, may be useful in characterizing the dietary patterns of populations. PMID:11848179

Ogawa, Keiko; Tsubono, Yoshitaka; Nishino, Yoshikazu; Watanabe, Yoko; Ohkubo, Takayoshi; Watanabe, Takao; Nakatsuka, Haruo; Takahashi, Nobuko; Kawamura, Mieko; Tsuji, Ichiro; Hisamichi, Shigeru

2002-01-01

346

Competition for one nutrient with internal storage and toxin mortality.  

PubMed

This study presents a mathematical model of two species competing in a chemostat for one resource that is stored internally, and who also compete through allelopathy. Each species produces a toxin to that increases mortality rate of its competitor. The two species system and its single species subsystem follow mass conservation constraints characteristic of chemostat models. Persistence of a single species occurs if the nutrient supply of an empty habitat allows it to acquire a threshold of stored nutrient quota, sufficient to overcome loss to outflow after accounting for the cost of toxin production. For the two-species system, a semitrivial equilibrium with one species resident is unstable to invasion by the missing species according to a similar threshold condition. The invader increases if acquires a stored nutrient quota sufficient to overcome loss to outflow and toxin-induced mortality, after accounting for the cost of the invader's own toxin production. If both semitrivial equilibria for the two-species system are invasible then there is at least one coexistence equilibrium. Numerical analyses indicate another possibility: bistability in which both semitrivial equilibria are stable against invasion. In such a case there is competitive exclusion of one species, whose identity depends on initial conditions. When there is a tradeoff between abilities to compete for the nutrient and to compete through toxicity, the more toxic species can dominate only under nutrient-rich conditions. Bistability under such conditions could contribute to the unpredictability of toxic algal blooms. PMID:23660151

Grover, James P; Wang, Feng-Bin

2013-08-01

347

Nutrient removal and starch production through cultivation of Wolffia arrhiza.  

PubMed

Wolffia arrhiza, a small weed found mostly in tropical and subtropical water environments, exhibits a high growth rate and consequently absorbs large amounts of nitrogen and phosphorus. Its vegetative frond contains 40% protein on a dry weight basis and its turion, which is the dormant form, has a similar starch content. The applicability of this weed to nutrient removal from secondary-treated waste water combined with starch resource production was evaluated. The nitrogen and phosphorus removal capabilities of the vegetative frond and the optimal conditions for inducing of the formation of turions from harvested biomass of vegetative fronds for the production of starch were investigated using artificial nutrient solutions. The vegetative frond showed high contents of nitrogen (6-7% of the total dry weight) and phosphorus (1-2% of the total dry weight). The nutrient removal rates of the vegetative frond were estimated to be 126 mg-N/m(2)/d and 38 mg-P/m(2)/d under a continuous flow condition. For turion formation from the vegetative fronds, a low nutrient concentration and a high plant density were most effective. Under the optimum conditions, the starch production rate was estimated to be 6 g-starch/m(2) (nutrient removal tank)/d. PMID:16232450

Fujita, M; Mori, K; Kodera, T

1999-01-01

348

Parallel Exploitation of Diverse Host Nutrients Enhances Salmonella Virulence  

PubMed Central

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

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

2013-01-01

349

Nutrient depletion in Bacillus subtilis biofilms triggers matrix production  

NASA Astrophysics Data System (ADS)

Many types of bacteria form colonies that grow into physically robust and strongly adhesive aggregates known as biofilms. A distinguishing characteristic of bacterial biofilms is an extracellular polymeric substance (EPS) matrix that encases the cells and provides physical integrity to the colony. The EPS matrix consists of a large amount of polysaccharide, as well as protein filaments, DNA and degraded cellular materials. The genetic pathways that control the transformation of a colony into a biofilm have been widely studied, and yield a spatiotemporal heterogeneity in EPS production. Spatial gradients in metabolites parallel this heterogeneity in EPS, but nutrient concentration as an underlying physiological initiator of EPS production has not been explored. Here, we study the role of nutrient depletion in EPS production in Bacillus subtilis biofilms. By monitoring simultaneously biofilm size and matrix production, we find that EPS production increases at a critical colony thickness that depends on the initial amount of carbon sources in the medium. Through studies of individual cells in liquid culture we find that EPS production can be triggered at the single-cell level by reducing nutrient concentration. To connect the single-cell assays with conditions in the biofilm, we calculate carbon concentration with a model for the reaction and diffusion of nutrients in the biofilm. This model predicts the relationship between the initial concentration of carbon and the thickness of the colony at the point of internal nutrient deprivation.

Zhang, Wenbo; Seminara, Agnese; Suaris, Melanie; Brenner, Michael P.; Weitz, David A.; Angelini, Thomas E.

2014-01-01

350

Light, nutrients and the growth of herbaceous forest species  

NASA Astrophysics Data System (ADS)

The herb layer of forests planted on former agricultural land often differs from that of old-growth forest. This study investigates if the expected increased nutrient availability in the shaded conditions of newly planted forests and the plasticity of the species to adjust their biomass allocation to different levels of light and nutrients help to explain these differences in the herb layers of the two forest types. In a greenhouse experiment biomass distribution and production of two species characteristic for the highly shaded forest floor, Circaea lutetiana and Mercurialis perennis, and two species more common in the forest-edge, Aegopodium podagraria and Impatiens parviflora were studied at different levels of light (2%, 8% and 66% of the full light level) and nutrients (30 and 300 kg N ha -1 per year). The main factor affecting allocation and biomass production was light availability. Nutrient supply only had a significant effect at the higher light levels. Species were mainly plastic to changes in light and the two species from the forest floor showed to be more rigid in allocation pattern than the species from the forest-edge. So, although the species from the forest-edge were more plastic, they did not profit from the increased nutrient supply because the main factor affecting biomass distribution and production was light availability.

Elemans, Marjet

2004-12-01

351

Contribution of complementary food nutrients to estimated total nutrient intakes for urban Guatemalan infants in the second semester of life.  

PubMed

Complementary foods (CF) are introduced earlier or later than appropriate in developing societies. They often contribute poorly to overall adequate micronutrient intake during the critical period for growth and development, which constitutes the period from 6 to 12 months of life. The objective of this study was to determine the contribution of the CF nutrients to the total estimated nutrient intake in infants in the second semester of life. Three non-consecutive 24-hour recalls interviews were conducted with mothers of 64 infants, aged 6-12 months on enrolment, from a convenience sample in a marginal urban settlement in Guatemala City. Retrospective recording of early introduction of pre- and post-lacteal feeding and introduction of first foods and beverages was included. Human milk intakes were estimated by a model based on assumptions that human milk plus CF exactly satisfied the infant's daily energy needs. The WHO/FAO Recommended Nutrient Intakes (RNI) were the standards for adequate nutrient consumption. Instances of exclusive breast feeding to 6 months were rare, with the introduction of CF earlier than recommended. Baby food in jars was mentioned most frequently as the first food offered. The contribution of CF increased with age through the second semester of life. CF contributed more of a nutrient than human milk in all instances. However,CF nutrient density for Ca, Fe, and Zn fell below international standard. Fortified sugar contributed excessive amounts of Vitamin A to the diets. We conclude that for most nutrients, intakes reached or exceeded recommendation levels, unusual within the CF experience in scientific literature. PMID:22094843

Hernández, Liza; Campos, Raquel; Enneman, Anke; Soto-Méndez, Maria José; Vossenaar, Marieke; Solomons, Noel W

2011-01-01

352

Combination air sampling cassette and nutrient media dish  

US Patent & Trademark Office Database

A combination air sampling cassette and nutrient media dish having base, orifice plate, and nutrient media dish assembly for the collection of airborne particles. The orifice plate includes a plurality of holes that brings the nutrient media dish into fluid communication with the ambient air. A pump is connected to the air outlet in the base to pull air into the orifice plate through the holes, over the culture media, and out through the air outlet. As the air passes through the holes in the orifice plate it is accelerated and results in the selected impaction of particles in the culture media. A cover fits over the assembly to protect the culture media prior to and after sampling.

2002-10-29

353

Assessing the susceptibility of two UK estuaries to nutrient enrichment  

NASA Astrophysics Data System (ADS)

The susceptibility of two UK estuaries, the Severn and Solva Estuaries to the risks and impacts of nutrient enrichment was investigated in this study by examining nutrients, dissolved oxygen (DO) and turbidity concentrations in the estuaries and applying a risk assessment model based on the UK's Comprehensive Studies Task Team (CSTT) modelling approach. Both estuaries were found to be nutrient enriched. However, there was no evidence of oxygen depletion in the Severn and algal blooms were not observed due to high turbidity, strong tidal currents and tidally induced vertical mixing conditions in the estuary. Although algal blooms were observed in the Solva Estuary, the estuary was well-oxygenated due to the relatively high water exchange rate and consistent rapid flushing in the estuary. The conditions in the Solva Estuary were predicted to be favourable for phytoplankton productivity and the wider potential implications for future water quality protection strategies in the Solva were discussed.

Kadiri, Margaret; Bockelmann-Evans, Bettina; Rauen, William B.

2014-10-01

354

Acclimation of Chlamydomonas reinhardtii to its nutrient environment.  

PubMed

To cope with low nutrient availability in nature, organisms have evolved inducible systems that enable them to scavenge and efficiently utilize the limiting nutrient. Furthermore, organisms must have the capacity to adjust their rate of metabolism and make specific alterations in metabolic pathways that favor survival when the potential for cell growth and division is reduced. In this article I will focus on the acclimation of Chlamydomonas reinhardtii, a unicellular, eukaryotic green alga to conditions of nitrogen, sulfur and phosphorus deprivation. This organism has a distinguished history as a model for classical genetic analyses, but it has recently been developed for exploitation using an array of molecular and genomic tools. The application of these tools to the analyses of nutrient limitation responses (and other biological processes) is revealing mechanisms that enable Chlamydomonas to survive harsh environmental conditions and establishing relationships between the responses of this morphologically simple, photosynthetic eukaryote and those of both nonphotosynthetic organisms and vascular plants. PMID:11079767

Grossman, A

2000-10-01

355

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."

356

Sediment and nutrient losses from an irrigated watershed.  

NASA Astrophysics Data System (ADS)

Irrigated agriculture is an essential part of stable food and fiber production. However, water returning from irrigated watersheds can contain excess sediment, nutrients and salts. Applying polyacrylamide to furrow irrigated fields reduces erosion 60 to 90%. Converting from furrow irrigation to sprinkler irrigation eliminates planned irrigation runoff necessary for uniform water application. Installing sediment ponds removes 50 to 80% of the suspended sediment from water before it flows back to major water bodies. In southern Idaho, irrigation watershed monitoring showed that implementing these conservation practices has reduced average suspended sediment loss from 460 kg/ha in 1970 to less than 100 kg/ha in 2005. These practices, however, have had less effect on soluble nutrients. Median nitrate concentrations have almost doubled from 1970 to 2005. Current research is focusing on identifying practices to reduce soluble nutrient losses.

Bjorneberg, D.; Ippolito, J.

2011-12-01

357

Nutrient dynamics management based on GIS modeling tools  

NASA Astrophysics Data System (ADS)

Nutrient sources and fate are investigated in the Evrotas, a temporary river in Greece. We assess field monitoring and modelling tools for the estimation of nutrient fate and transport through various diffuse pathways. The `total daily maximum load' approach is used to estimate the nutrient flux status by flow class and measures are recommended and applied for each flow status. Using this approach in Evrotas basin, it was estimated that almost 60% of the river network fails to meet nitrogen criteria and 50% phosphate criteria. We recommend that existing well-documented remediation measures such as reforestation of the riparian area should be implemented to achieve load reduction in close conjunction with social needs.

Tzoraki, Ourania; Nikolaidis, Nikolaos P.; Kassotaki, Eliza; Cooper, David; Papadoulakis, Vasilis

2013-08-01

358

Method and apparatus for determining nutrient stimulation of biological processes  

DOEpatents

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.

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

359

Method and apparatus for determining nutrient stimulation of biological processes  

DOEpatents

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.

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

360

Marine nutrient contributions to tidal creeks in Virginia: spawning marine fish as nutrient vectors to freshwater ecosystems  

NASA Astrophysics Data System (ADS)

Coastal freshwater streams are typically viewed as conduits for the transport of sediment and nutrients to the coasts. Some coastal streams however experience seasonal migrations of anadromous fish returning to the freshwater to spawn. The fish may be vectors for the delivery of marine nutrients to nutrient poor freshwater in the form of excreted waste and post-spawning carcasses. Nutrients derived from marine sources are 13C, 15N and 34S enriched relative to nutrients in freshwater. Here we examine sediment, particulate organic matter (POM), invertebrates and fish in two tidal freshwater tributaries of the James River USA. The d15N of POM became elevated (from 3.8 to 6.5%), coincident with the arrival of anadromous river herring (Alosa sp), indicating a pulse of marine nitrogen. However, the elevated 15N was not observed in sediment samples or among invertebrates, which did not experience a seasonal isotopic shift (there were significant differences however among the guilds of invertebrate). Anadromous Alosa aestivalis captured within the tidal freshwater were 13C and 34S enriched (-19.3 and 17.2%, respectively) relative to resident freshwater fishes (-26.4 and 3.6% respectively) captured within 2 weeks of the Alosa. Although it is likely that marine derived nitrogen was detected in the tidal freshwater, it was not in sufficient abundance to change the isotope signature of most ecosystem components.

Macavoy, S. E.; Garman, G. C.

2006-12-01

361

Nutrient leaching from mixed-species Florida residential landscapes.  

PubMed

Nutrient losses from residential lawns and landscapes can negatively impact water quality. Information about nutrient leaching from established residential landscapes containing a mixture of woody ornamental plants and turfgrass is limited. The objective of our study was to determine the effect of vegetation cover (turfgrass vs. woody ornamental) on nutrient leaching from established landscapes. Nine drainage lysimeters were planted with three vegetation treatments with the following coverage: (i) 60% turfgrass, 40% ornamental; (ii) 75% turfgrass, 25% ornamental; and (iii) 90% turfgrass, 10% ornamental. Daily leachate samples were collected and combined to produce weekly flow-weighted samples for 1 yr. Leachate samples were analyzed for total Kjeldahl N (TKN), nitrate (+ nitrite)-N (NO), ammonium-N (NH-N), and dissolved reactive phosphorus (DRP). The ratio of actual evapotranspiration (ET) to reference evapotranspiration (ET) was similar among treatments. However, drainage from the 90% turfgrass lysimeters was periodically higher than from the 60 and/or 75% turfgrass treatments. In most cases, leachate N and P concentrations and loads followed the same trend as drainage. The addition of shrubs in the 60 and 75% turfgrass treatments reduced leachate when rainfall was low and irrigation was the main water input. We suggest that established woody ornamental plants are more effective at absorbing water and nutrients than turfgrass due, in part, to increased root biomass and deeper rooting of established woody plants, which allows for more efficient uptake of soil water and nutrients. The use of woody plants in residential landscapes can reduce nutrient leaching in urban areas. PMID:24216431

Qin, Zhixuan; Shober, Amy L; Beeson, Richard C; Wiese, Christine

2013-09-01

362

A changing nutrient regime in the Gulf of Maine  

NASA Astrophysics Data System (ADS)

Recent oceanographic observations and a retrospective analysis of nutrients and hydrography over the past five decades have revealed that the principal source of nutrients to the Gulf of Maine, the deep, nutrient-rich continental slope waters that enter at depth through the Northeast Channel, may have become less important to the Gulf's nutrient load. Since the 1970s, the deeper waters in the interior Gulf of Maine (>100 m) have become fresher and cooler, with lower nitrate (NO 3) but higher silicate (Si(OH) 4) concentrations. Prior to this decade, nitrate concentrations in the Gulf normally exceeded silicate by 4-5 ?M, but now silicate and nitrate are nearly equal. These changes only partially correspond with that expected from deep slope water fluxes correlated with the North Atlantic Oscillation, and are opposite to patterns in freshwater discharges from the major rivers in the region. We suggest that accelerated melting in the Arctic and concomitant freshening of the Labrador Sea in recent decades have likely increased the equatorward baroclinic transport of the inner limb of the Labrador Current that flows over the broad continental shelf from the Grand Banks of Newfoundland to the Gulf of Maine. That current system now brings a greater fraction of colder and fresher deep shelf waters into the Gulf than warmer and saltier offshore slope waters which were previously thought to dominate the flux of nutrients. Those deep shelf waters reflect nitrate losses from sediment denitrification and silicate accumulations from rivers and in situ regeneration, which together are altering the nutrient regime and potentially the structure of the planktonic ecosystem.

Townsend, David W.; Rebuck, Nathan D.; Thomas, Maura A.; Karp-Boss, Lee; Gettings, Rachel M.

2010-04-01

363

Allocation of nutrients to somatic tissues in young ovariectomized grasshoppers.  

PubMed

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 ¹?N, 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

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

2010-11-01

364

Evidence for sensitivity of dune wetlands to groundwater nutrients.  

PubMed

Dune slacks are seasonal wetlands, high in biodiversity, which experience considerable within-year and between-year variations in water-table. They are subject to many pressures including climate change, land use change and eutrophication. Despite their biological importance and the threats facing them, the hydrological and nutrient parameters that influence their soil properties and biodiversity are poorly understood and there have been no empirical studies to date testing for biological effects in dune systems resulting from groundwater nutrients at low concentrations. In this study we examined the impact of groundwater nutrients on water chemistry, soil chemistry and vegetation composition of dune slacks at three distance classes (0-150 m, 150-300 m, 300-450 m) away from known (off-site) nutrient sources at Aberffraw dunes in North Wales, whilst accounting for differences in water-table regime. Groundwater nitrate and dissolved inorganic nitrogen (DIN) and soil nitrate and nitrite all had significantly higher concentrations closest to the nutrient source. Multivariate analysis showed that although plant species composition within this site was primarily controlled by water table depth and water table fluctuation, nitrogen from groundwater also influenced species composition, independently of water table and soil development. A model containing all hydrological parameters explained 17% of the total species variance; an additional 7% was explained following the addition of NO3 to this model. Areas exposed to elevated, but still relatively low, groundwater nutrient concentrations (mean 0.204 mg/L+/-0.091 of DIN) had greater abundance of nitrophilous species and fewer basipholous species than in areas with lower concentrations. This shows that clear biological impact occurs below previously suggested DIN thresholds of 0.20-0.40 (mg/L). PMID:24846404

Rhymes, Jennifer; Wallace, Hilary; Fenner, Nathalie; Jones, Laurence

2014-08-15

365

Efficiency of nutrient acquisition by fine roots and mycorrhizae  

SciTech Connect

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.

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

1995-07-01

366

Predator-Driven Nutrient Recycling in California Stream Ecosystems  

PubMed Central

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

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

2013-01-01

367

Managing Crop Nutrients Through Soil, Manure and Effluent Testing  

E-print Network

Benef_its of Manure and Ef_f_luent Livestock manures are often rich in plant nutrients. Studies have shown that up to 75 percent of the nitrogen (N), 60 percent of the phosphorus (P 2 O 5 ) and 80 percent of the potas- sium (K 2 0) fed to dairy...Benef_its of Manure and Ef_f_luent Livestock manures are often rich in plant nutrients. Studies have shown that up to 75 percent of the nitrogen (N), 60 percent of the phosphorus (P 2 O 5 ) and 80 percent of the potas- sium (K 2 0) fed to dairy...

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

1998-12-10

368

Mathematical modelling of plant water and nutrient uptake  

NASA Astrophysics Data System (ADS)

In this presentation I will describe a model of plant water and nutrient uptake and how to translate this model and experimental data from the single root scale to the root branching structure scale. The model starts at the single root scale and describes the water and nutrient movement in the soil using Richards' equation (water uptake) and diffusion-convection equation (nutrient uptake). The water and nutrient uptake in the single root scale model is represented by boundary conditions. In the case of nutrient uptake this has the form of a non-linear Michaelis-Menten uptake law and in the case of water this is given by a soil-xylem pressure difference boundary condition. The flow of water in the xylem is modeled as Poiseuille flow. We solve the single root scale models using the analytic approximate technique of asymptotic expansions similar to Oseen expansions known from fluid dynamics. We will then discuss how to use the analytic expression to estimate the water and nutrient uptake by growing root branching systems. We model the growth of the root system using a dynamic population model to describe the branching and elongation of roots in the branching system. This root branching population model results in a hyperbolic equation similar to age dependent population models and it can be solved fully analytically using the method of characteristics. Thus we have a fully analytic description of the root branching system evolution. We use this branching model to estimate the nutrient uptake in a scenario when the competition between subbranches is small, i.e., as it is in the case of phosphate, potassium and arsenic. We compare our approximate analytic model to a full 3d simulation of the root system phosphate uptake and find that the analytic model almost perfectly reproduces the 3d numerical model. In addition the analytic model can be included in larger field/catchment/climate scale models something which is not practically possible with the numerical simulations due to their high computational burden. As a further development of the analytic model we extend it to take into account more details about the root morphology, such as the branching angle between roots, to calculate the evolution of the soil moisture and nutrient concentration profiles due to surface fertilisation and rainfall events. Using this model we are able to determine the relationship between the rainfall events and fertiliser movement into the soil profile. We find that there is a critical rate of rainfall below which the fertilizer (or pollutant) movement into the deeper layers of the soil is impeded due to the development of a slowly varying fluid saturation profile.

Roose, Tiina

2010-05-01

369

Basin characteristics and nutrient losses: the EUROHARP catchment network perspective.  

PubMed

The EC-funded EUROHARP project studies the harmonisation of modelling tools to quantify nutrient losses from diffuse sources. This paper describes a set of study areas used in the project from geographical conditions, to land use and land management, geological and hydro-geological perspectives. The status of data availability throughout Europe in relation to the modelling requirements is presented. The relationships between the catchment characteristics and the nutrient export are investigated, using simple data available for all the catchments. In addition, this study also analyses the hydrological representativity of the time series utilised in the EUROHARP project. PMID:19280031

Bouraoui, F; Grizzetti, B; Adelsköld, G; Behrendt, H; de Miguel, I; Silgram, M; Gómez, S; Granlund, K; Hoffmann, L; Kronvang, B; Kvaernø, S; Lázár, A; Mimikou, M; Passarella, G; Panagos, P; Reisser, H; Schwarzl, B; Siderius, C; Sileika, A S; Smit, A A M F R; Sugrue, R; Vanliedekerke, M; Zaloudik, J

2009-03-01

370

Defining Powerhouse Fruits and Vegetables: A Nutrient Density Approach  

PubMed Central

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

2014-01-01

371

Nutrient resources for crop production in the tropics  

PubMed Central

For the foreseeable future a majority of the population, and almost all the mal- and under-nourished, will continue to be found in the tropics and subtropics. Food security in these parts of the world will have to be met largely from local resources. The productivity of the land is to a large extent determined by the fertlity of the soil, which in turn is mostly determined by its organic matter content and stored nutrients. Soil organic matter is readily lost when organic matter inputs are reduced upon cultivation and more so upon intensification. The concomitant loss of topsoil and possible exposure of subsoil acidity may cause further soil degradation.
Plant nutrients to replenish what is yearly taken from the soil to meet the demands for food and fibre amount to 230 million tonnes (Mt). Current fertilizer consumption stands at about 130 Mt of N, P2O5,and K2O, supplemented by an estimated 90 Mt of N from biological nitrogen fixation worldwide. Although 80 per cent of the population lives in the developing world, only half the world's fertilizer is consumed there. Yet, as much as 50% of the increase in agricultural productivity in the developing world is due to the adoption of fertilizers. World population growth will cause a doubling in these nutrients requirements for the developing world by 2020, which, in the likely case of inadequate production, will need to be met from soil reserves. Because expansion of the cultivable land area is reaching its limits, the reliance on nutrient inputs and their efficient use is bound to grow.
With current urban expansion, nutrients in harvested products are increasingly lost from the rural environment as a whole. Estimates of soil nutrient depletion rates for sub-Saharan Africa (SSA) are alarmingly high. The situation may be more favourable in Latin America and Asia where fertilizer inputs are tenfold those of SSA. Closing the nutrient cycle at a community level in rural areas may be tedious; on an inter-regional level it is associated with considerable costs of collection, detoxification and transportation to the farms. Yet, at the rate at which some of the non-renewable resources such as phosphorus and potassium are being exploited, recycling of these nutrients will soon be required.

Vlek, P. L. G.; Kuhne, R. F.; Denich, M.

1997-01-01

372

PAS Kinase: A Nutrient Sensing Regulator of Glucose Homeostasis  

PubMed Central

Per-Arnt-Sim (PAS) kinase (PASK, PASKIN, and PSK) is a member of the group of nutrient sensing protein kinases. These protein kinases sense the energy or nutrient status of the cell and regulate cellular metabolism appropriately. PAS kinase responds to glucose availability and regulates glucose homeostasis in yeast, mice, and man. Despite this pivotal role, the molecular mechanisms of PAS kinase regulation and function are largely unknown. This review focuses on what is known about PAS kinase, including its conservation from yeast to man, identified substrates, associated phenotypes and role in metabolic disease. PMID:24265199

DeMille, Desiree; Grose, Julianne H.

2014-01-01

373

A mixed-layer nutrient climatology of Leeuwin Current and Western Australian shelf waters: Seasonal nutrient dynamics and biomass  

NASA Astrophysics Data System (ADS)

We present a seasonal climatology of the nutrient environment for waters off southwestern Australia with the intention of identifying spatial and seasonal characteristics of the nutrient environment and identify situations where the shelf may be susceptible to anthropogenic nutrient stress. The seasonal climatologies were generated from historical hydrographic data contained within the CSIRO Atlas of Regional Seas. The data presented here suggest the surface waters of the southwestern Australian shelf, the Leeuwin Current and offshore are all low in nitrogen (less than 0.5 ?M) year round and that primary productivity is nitrogen limited. The shelf waters contain some dissolved phosphate, at relatively low levels (up to 0.25 ?M) but diatom production may be limited by low levels of silicic acid (silicate) which are less than 2 ?M year round. The Leeuwin Current is largely devoid of phosphate but contains reasonably high levels of silicate (up to 4 ?M) and may be a silicate source to surrounding waters. A cross-shelf gradient in chlorophyll a biomass suggests that terrestrial nutrient sources make an important contribution to primary productivity. Offshore, a seasonal (wintertime) increase in chlorophyll a biomass coincides with a deepening of the mixed layer and is presumably supported by the mixing of deep water nutrients or chlorophyll from the deepwater maximum into the euphotic zone associated with this deepening. Further observations, particularly cross-shelf profiles from winter and profiles along the core of the Leeuwin Current, are required to fully separate the influence of the Leeuwin Current from other potential seasonal nutrient sources.

Lourey, Martin J.; Dunn, Jeff R.; Waring, Jason

2006-01-01

374

Managing Nutrients on Wisconsin Soils Webinar Workshop2013  

E-print Network

Managing Nutrients on Wisconsin Soils Webinar Workshop­2013 Webinar Agenda Date/Time Topic Speaker is an intensive nine- hour webinar designed for agency and industry personnel who desire to have a more in depth for the webinar is required for each participant and the fee is $90 per person. Registration will close on March

Balser, Teri C.

375

Parasitic and Infectious Disease Responses to Changing Global Nutrient Cycles  

E-print Network

) are a significant threat to human, livestock, and wildlife health and are changing dramatically in the face of human cycles. Humans have now altered the nitrogen (N) cycle to an astonishing degree, and those changes regulated by ecological interactions, changes in nutrients are likely to affect their dynamics

McKenzie, Valerie

376

QUALITATIVE AND QUANTITATIVE NUTRIENT REQUIREMENTS OF FISHES: A REVIEW}  

E-print Network

in the diet include thiamine, riboflavin, pyridoxine, niacin, pantothenic acid, ascorbic acid, choline, folic Qualitative and quantitative protein, amino acid, lipid, fatty acid, carbohydrate, vitamin, and min- eral acid, vitamin, and mineral requirements of fishes, since recent research with these nutrients has

377

Nutrient and food intakes differ among Latina subgroups during pregnancy  

PubMed Central

Objective To document nutrient and food group serving intakes from food sources among Latina subgroups living in the same geographical area. Design A cross-sectional study. Nutrient and food group serving intakes were assessed by means of a 24 h recall administered immediately after a prenatal survey. Setting Hartford, CT, USA. Subjects A total of 233 low-income pregnant Latinas. For analyses, Latinas were classified into two groups on the basis of self-reported ethnic identity: Puerto Ricans and non-Puerto Rican Latinas. Results Puerto Rican Latinas were more likely than non-Puerto Rican Latinas to be more acculturated and to consume foods (i.e. processed meat, cheese, soft drinks) and higher levels of nutrients (i.e. fat, SFA, MUFA, trans fatty acids) that have been implicated in the development of chronic diseases. By contrast, non-Puerto Rican Latinas were more likely to consume foods (i.e. fruits, dark green/yellow vegetables, tomatoes, non-starchy vegetables) and higher levels of nutrients (i.e. fibre, vegetable protein, folate, ?-carotene) that promote health when compared with Puerto Rican Latinas. Conclusions Findings suggest that acculturation may play a role in dietary intake. Clinicians and dietitians need to be aware of these differences to encourage healthy eating patterns among more acculturated pregnant Latina clients. PMID:21729472

Hromi-Fiedler, Amber; Bermudez-Millan, Angela; Segura-Perez, Sofia; Perez-Escamilla, Rafael

2011-01-01

378

Nerveless and gutsy: intestinal nutrient sensing from invertebrates to humans  

PubMed Central

The increasingly recognized role of gastrointestinal signals in the regulation of food intake, insulin production and peripheral nutrient storage has prompted a surge of interest in studying how the gastrointestinal tract senses and responds to nutritional information. Identification of metabolically important intestinal nutrient sensors could provide potential new drug targets for the treatment of diabetes, obesity and gastrointestinal disorders. From a more fundamental perspective, the study of intestinal chemosensation is revealing novel, non-neuronal modes of communication involving differentiated epithelial cells. It is also identifying signalling mechanisms downstream of not only canonical receptors but also nutrient transporters, thereby supporting a chemosensory role for “transceptors” in the intestine. This review describes known and proposed mechanisms of intestinal carbohydrate, protein and lipid sensing, best characterized in mammalian systems. It also highlights the potential of invertebrate model systems such as C. elegans and Drosophila melanogaster by summarizing known examples of molecular evolutionary conservation. Recently developed genetic tools in Drosophila, an emerging model system for the study of physiology and metabolism, allow the temporal, spatial and high-throughput manipulation of putative intestinal sensors. Hence, fruit flies may prove particularly suited to the study of the link between intestinal nutrient sensing and metabolic homeostasis. PMID:22248674

Miguel-Aliaga, Irene

2012-01-01

379

Modelling and simulation of nutrient dispersion from coated fertilizer granules  

NASA Astrophysics Data System (ADS)

The usage of Controlled-Release Fertilizer (CRF) is essential in plants and crops to fulfill the need and requirement for the modern agriculture which now feeds 6 billion people. Therefore modeling and simulation of nutrient release from coated fertilizer has become the best method to study the behavior of some parameters toward water saturation in and nutrient release from the coated-fertilizer granule. This paper is the improvement development of modeling and computer simulation by Basu [1] which include some of the factors affecting the water saturation time and nutrient release time from a coated-fertilizer. The effect of granule radius, the diffusivity of water and nutrient, the temperature of surrounding, the contact areas and the characteristic of the coating are studied and the simulation was developed using MATLAB software. The studies and understanding of this project is very important and useful especially to determine the important parameters in the manufacturing process of the coated-fertilizer granule and also will be useful for the farmers/users in the selection of the best fertilizers for their crops.

Razali, Radzuan; Daud, Hanita; Nor, Shafiq Mohd.

2014-10-01

380

NUTRIENT CONTROL OF HUNGER BY EXTRINSIC GASTROINTESTINAL1 NEURONS2  

E-print Network

are key determinants in the control of appetite32 and food intake. In normal individuals a precise in terms of control of food intake by the16 central nervous system (CNS). Nutrient sensing that20 control food intake and body weight, which might pave the way to future approaches in the21

Paris-Sud XI, Université de

381

NONPOINT SOURCE - STREAM NUTRIENT LEVEL RELATIONSHIPS: A NATIONWIDE STUDY  

EPA Science Inventory

National Eutrophication Survey (NES) data for a nationwide collection of 928 non-point source watersheds were studied for relationships between macro-drainage area characteristics (particularly land use) and nutrient levels in streams. Both the total and inorganic forms of phosph...

382

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...

383

OZONE ALTERS THE CONCENTRATIONS OF NUTRIENTS IN BEAN TISSUE  

EPA Science Inventory

Studies were conducted to determine the impact of ozone on the nutrient concentrations in tissue from various organs of beans (Phaseolus vulgaris L. cv Bush Bluelake 290). The plants were exposed to episodic concentrations of ozone in open-top field exposure chambers from soon af...

384

Masting in whitebark pine (Pinus albicaulis) depletes stored nutrients.  

PubMed

• 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

Sala, Anna; Hopping, Kelly; McIntire, Eliot J B; Delzon, Sylvain; Crone, Elizabeth E

2012-10-01

385

Nutrient Management Module No. 13 Regulation and Management  

E-print Network

Nutrient Management Module No. 13 Manure and Biosolids: Regulation and Management by Clain Jones, with the focus on manure and stabilized municipal wastewater sludge (`biosolids') management. Objectives 1. Understand pros and cons of manure and biosolids application 2. Distinguish between animal feeding operations

Lawrence, Rick L.

386

Lepidium latifolium : plant nutrient competition-soil interactions  

Microsoft Academic Search

Exotic weeds are invading rangelands of the western United States at unprecedented rates. Understanding plant-soil relationships and competitive interactions of invasive weeds is crucial in long-term control strategies. In a greenhouse experiment, we investigated the influence of soil nutrient depletion on plant growth and plant competition between the exotic invasive weeds, Lepidium latifolium (invading wetlands) and Bromus tectorum (invading a

Robert R. Blank; Robert G. Qualls; James A. Young

2002-01-01

387

Trophic state, eutrophication and nutrient criteria in streams  

Microsoft Academic Search

Trophic state is the property of energy availability to the food web and defines the foundation of community integrity and ecosystem function. Describing trophic state in streams requires a stoichiometric (nutrient ratio) approach because carbon input rates are linked to nitro- gen and phosphorus supply rates. Light determines the source of carbon. Cross system analyses, small exper- iments and ecosystem

Walter K. Dodds

2007-01-01

388

Stoichiometric nutrient balance and origin of coastal eutrophication  

Microsoft Academic Search

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)

Dubravko Justi?; Nancy N. Rabalais; R. Eugene Turner

1995-01-01

389

Nutrient and grazing influences on a subtropical seagrass community  

E-print Network

of the dominant seagrass and macroalgae. One site was eutrophic, the other mesotrophic to oligotrophc. Nutrients with the dominance of this macroalga in the eutrophic portion of the bay and with previous work showing biomass of the dominant seagrass Tha- lassia testudinum at the eutrophic site but not at the mesotrophic

McGlathery, Karen

390

Retention of Riverine Sediment and Nutrient Loads by Coastal Plain  

E-print Network

accumulated a very large amount of material compared to their annual river loads of sediment (median among floodplain inundation retained greater proportions of riverine loads of nitrogen and phosphorus, but systemsRetention of Riverine Sediment and Nutrient Loads by Coastal Plain Floodplains Gregory B. Noe

391

Effect of potassium on moringa plants growth in nutriente solution  

Microsoft Academic Search

The work was carried out to evaluate the effects of K + rates on the initial growth as well as on the partition and accumulation of this element in roots, stems and leaves of moringa (Moringa oleifera Lam.) plants. A pot (0.5 dm 3) experiment was carried out under greenhouse conditions using river sand as substrate irrigated with nutrient solution

Lucia Helena; Ricardo Almeida Viégas; Ana Carolina; Feitosa de Vasconcelos; Hugo Vieira

392

Chlorophyll a: Nitrogen was the limiting nutrient, with significantly higher  

E-print Network

grow in two or three weeks. We wished to determine how the rate of biomass growth changes in response to nutrient additions over a longer period of time (ie. more than 3 weeks). RESULTS METHODS Preparation, Denise Bruesewitz (Colby College, Waterville, ME) and Jennifer Tank (University of Notre Dame, Notre Dame

Hall, Sharon J.

393

DIAGNOSTIC INDICATORS OF STREAM IMPAIRMENT AS A RESULT OF NUTRIENTS  

EPA Science Inventory

The main goal of this project is to provide information needed by States to set nutrient criteria at a level appropriately protective of their water bodies' aquatic life uses. The information that would be generated by this study is critically needed in order for States to use it...

394

Nutrients by the Numbers: Using Math to Explore Nutrition  

NSDL National Science Digital Library

Students strengthen their percentage and fraction skills by comparing the nutritional values of similar food products. They individually calculate their own daily intake of various nutrients and compare their diets to recommended daily percentages. Discussion questions, additional activities, and suggestions for assessment are included with the lesson plan.

Dekorne, Clayton; Khan, Javaid

2002-10-03

395

Identifying the Source of Nutrient Contamination in a Lagoon System  

Microsoft Academic Search

Nutrient concentrations within watercourses are often associated with the input of sewage or the runoff of fertilizers. Due to population increases, there has been a dramatic rise in the amount of fertilizer applied to land, as well as in the further development of sewage treatment plants (STPs), both of which can lead to significant discharges with associated eutrophication risks in

D. Wayland; D. P. Megson; S. M. Mudge; J. D. Icely; A. Newton

2008-01-01

396

Nutrient chemistry of the water column of Lake Tanganyika  

Microsoft Academic Search

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

J. M. EDMOND; R. F. STALLARD; H. CRAIG; V. CRAIG; R. F. WEISS; G. W. COULTER

1993-01-01

397

SEDIMENT AND NUTRIENT ACCUMULATION WITHIN LOWLAND BOTTOMLAND ECOSYSTEMS  

E-print Network

SEDIMENT AND NUTRIENT ACCUMULATION WITHIN LOWLAND BOTTOMLAND ECOSYSTEMS: AN EXAMPLE FROM, and transformations are important environmental functions of riverine forested wetland ecosystems, yet documentation. This accumulated sediment contains a coarsely estimated 5% and 27% of the annual nitrogen and phosphorus loads

398

Nutrient fate in aquacultural systems for waste treatment  

Microsoft Academic Search

Twelve small, recirculating aquacultural systems were operated for livestock waste treatment to determine nutrient fate. Each system consisted of a 730-L fish tank coupled in a recirculating loop with three sand beds (serving as biofilters) in parallel. Fish (Tilapia species) were grown in the tanks while cattails, reed canary grass, and tomatoes were grown in separate sand beds. Swine waste

J. H. Dontje; C. J. Clanton

1999-01-01

399

Assessment of heat treatment for nutrient preservation in seawater samples  

Microsoft Academic Search

Heat treatments, pasteurization and tyndallization, were tested as potential techniques for preservation of seawater samples for subsequent determination of nutrients (nitrate, nitrite, ammonia and phosphate), either for aquatic studies or for production of reference materials. The advantage over other methods is two-fold: there is no addition of preservative and no special equipment is required for sample storage. The effect of

Alain Aminot; Roger Kérouel

1997-01-01

400

Microstructure and nutrient distribution in oats: influence on quality  

Microsoft Academic Search

Oats have long been recognized as having superior quality among cereals with respect to protein and lipid composition as well as soluble dietary fibre (beta-glucan). The microstructure and chemistry of oats influence oat quality, and thus are determinants of the end products derived from oats. Light and scanning electron microscopies have been used to elucidate microstructure and nutrient distribution in

S. Shea Miller; Judith Frégeau-Reid

2009-01-01

401

Nutrient fluxes from the Danube basin to the Black sea  

Microsoft Academic Search

This paper deals with the state of the art of quantification of sources, pathways and sinks of nutrients in the Danube Basin and their transport form the catchment to the Black Sea. It shows main results of emission estimates to surface waters and the Danube Water Quality Model approach to link this emissions estimates to measured water monitoring data. The

M. Zessner; J. van Gils

402

Hydromorphological control of nutrient cycling in complex river floodplain systems  

Microsoft Academic Search

Riparian zones and floodplains are key components within river ecosystems controlling nutrient cycling by promoting transformation processes and thus, act as biogeochemical hot spots. The intensity of these processes depends on the exchange conditions (the connectivity) with the main channel and the morphological setting of the water bodies. At the landscape scale, three interrelated principles of hydromorphological dynamics can be

T. Hein; E. Bondar-Kunze; M. Felkl; H. Habersack; M. Mair; G. Pinay; M. Tritthart; N. Welti

2009-01-01

403

Microbial Indicators of Nutrient Enrichment: A Mesocosm Study  

Microsoft Academic Search

Microbial communities are in close contact with the wetland soil microenvironment and can therefore function effectively as monitors of soilpollution.Theobjectiveofthisstudywastodeterminechangesinthe functional responses of microbial communities as a result of an external input of nutrients, while controlling for vegetation. A controlled ex- periment was performed at the mesocosm scale, consisting of two 1 m by 13 m raceways containing an organic

R. Corstanje; K. R. Reddy

2006-01-01

404

Dietary Protein: An Essential Nutrient For Bone Health  

Microsoft Academic Search

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,

Jean-Philippe Bonjour

2005-01-01

405

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...

406

Nutrient status: a missing factor in phenological and pollen research?  

PubMed Central

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

Jochner, Susanne

2013-01-01

407

EFFECTS OF TOXIC CHEMICAL ON NUTRIENT CYCLING PROCESSES IN SOIL  

EPA Science Inventory

Assessing the risk of toxic chemicals to soil nutrient cycling processes involves an understanding of the potential for chemical effects on the diversity and the activity of the microbial communities and higher life forms in the natural system. ssessments of risk associated with ...

408

Original article The effect of feed enzymes on nutrient  

E-print Network

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

Paris-Sud XI, Université de

409

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...

410

Aquaponic Systems: Nutrient recycling from fish wastewater by vegetable production  

Microsoft Academic Search

This chapter describes the possibility to combine wastewater treatment in recirculating aquaculture systems (RAS) with the production of crop plants biomass. In an aquaponic RAS established in Waedenswil, Zurich, the potential of three crop plants was assessed to recycle nutrients from fish wastewater. A special design of trickling filters was used to provide nitrification of fish wastewater: Light-expanded clay aggregate

Andreas Graber; Ranka Junge

2009-01-01

411

CELL SIGNALING & DEVELOPMENT Target of Rapamycin (TOR) in Nutrient Signaling  

E-print Network

(carbon, nitrogen, phosphate, stress, caffeine): 1183 The EGO complex: 1184 Feedback loop.Loewith@unige.ch Genetics, Vol. 189, 1177­1201 December 2011 1177 #12;CONTENTS, continued TORC1 inhibits stress responses: 1189 Environmental stress response: 1189 Nutrient uptake and intermediary metabolism: 1189 Autophagy

Halazonetis, Thanos

412

Feasibility of nutrient recovery from industrial sludge by vermicomposting technology  

Microsoft Academic Search

Transformation of industrial sludges into vermicompost is of double interest: on the one hand, a waste is converted into value added product, and, on the other, it controls a pollutant that is a consequence of increasing industrialization. This paper reports the feasibility of utilization of vermicomposting technology for nutrient recovery from industrial sludge in laboratory scale experiment employing Eisenia fetida

Anoop Yadav; V. K. Garg

2009-01-01

413

Introduction Wheat development is affected by nutrients, water, light,  

E-print Network

. We know that planted seeds will germinate and emerge after a certain pe- riod of time ­ dependingIntroduction 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

Liskiewicz, Maciej

414

Oviposition behavior partitions aquatic landscapes along predation and nutrient gradients  

Microsoft Academic Search

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.

C. A. Binckley; W. J. Resetarits Jr

2008-01-01

415

Long-Term Nutrient Performance in a Bioinfiltration Rain Garden  

EPA Science Inventory

The goals of this study is to gain a better understanding of the nutrients and metals removal mechanisms involved in a bioinfiltration stormwater abatement system, predict the useful life of a bioinfiltration BMP for the removal of certain contaminants and assess toxicity of stor...

416

Consideration of nutrient levels in studies of cognitive decline.  

PubMed

Epidemiological studies suggest that certain micronutrients may improve or maintain cognitive function. Consistent demonstration of benefits in intervention trials has been elusive, possibly because most intervention trials do not select subjects on the basis of nutrient status and/or intake. The objective of this review was to identify levels of intake or markers of nutrient insufficiency that define at-risk older adult populations to determine whether these populations will benefit from nutritional intervention. This review examines evidence from interventional and prospective observational studies that evaluated the effects of folate, vitamin B12 , and vitamin E on cognitive decline in older populations. The studies suggest that supplementation may protect against cognitive decline when serum folate is <12?nmol/L or vitamin E intake is <6.1?mg/day. The literature is inadequate to define a level for vitamin B12 . Epidemiological studies investigating the relations of nutrients to cognitive decline should consider nutrient status in the reporting and interpretation of results. Randomized trials should design inclusion and exclusion criteria to select individuals with low intake and to disallow multivitamin intake. These recommendations may be useful for the design of valid trials and to advance the current understanding of nutrition and neurological diseases. PMID:25323849

Barnes, Jennifer L; Tian, Min; Edens, Neile K; Morris, Martha Clare

2014-11-01

417

NRCS Nutrient Management Field Team Coordinators Counties in Field Office  

E-print Network

v.09.2013 NRCS Nutrient Management Field Team Coordinators Counties in Field Office Service Area Technical Center West Area Clarion Tim Elder Timothy.Elder@pa.usda.gov Crawford County W1 Waterford Waterford Tom Lamont Thomas.Lamont@pa.usda.gov Erie County W1 Meadville Waterford Tom Lamont Thomas

Guiltinan, Mark

418

Effects of Exotic Plant Invasions on Soil Nutrient Cycling Processes  

Microsoft Academic Search

Although it is generally acknowledged that invasions by exotic plant species represent a major threat to biodiversity and ecosystem stability, little attention has been paid to the potential impacts of these invasions on nutrient cycling processes in the soil. The literature on plant–soil interactions strongly suggests that the introduction of a new plant species, such as an invasive exotic, has

Joan G. Ehrenfeld

2003-01-01

419

Nutrient analysis of the Beef Alternative Merchandising cuts.  

PubMed

The objective of this study was to generate raw and cooked nutrient composition data to identify Quality Grade differences in proximate values for eight Beef Alternative Merchandising (BAM) cuts. The data generated will be used to update the nutrient data in the USDA National Nutrient Database for Standard Reference (SR). Beef Rib, Oven-Prepared, Beef Loin, Strip Loin, and Beef Loin, Top Sirloin Butt subprimals were collected from a total of 24 carcasses from four packing plants. The carcasses were a combination of USDA Yield Grades 2 (n=12) and 3 (n=12), USDA Quality Grades upper two-thirds Choice (n=8), low Choice (n=8), and Select (n=8), and two genders, steer (n=16) and heifer (n=8). After aging, subprimals were fabricated into the BAM cuts, dissected, and nutrient analysis was performed. Sample homogenates from each animal were homogenized and composited for analysis of the following: proximate analysis, long chain and trans-fatty acids, conjugated linoleic acid, total cholesterol, vitamin B-12, and selenium. This study identified seven BAM cuts from all three Quality Grades that qualify for USDA Lean; seven Select cuts that qualify for USDA Extra Lean; and three Select cuts that qualify for the American Heart Association's Heart Healthy Check. PMID:23261533

Desimone, T L; Acheson, R A; Woerner, D R; Engle, T E; Douglass, L W; Belk, K E

2013-03-01

420

Phytoplankton growth on organic nutrients from trash fish  

Microsoft Academic Search

Trash fish is common feed for caged fish in marine aquaculture. Most feed is not eaten and enters the water surrounding fish farms. The organic matter in trash fish is a nutrient source contributing to aquatic eutrophication impacts such as algal blooms and low oxygen. The objective of this study was to examine whether phytoplankton utilized organic matter of trash

Yongli Gao; Kedong Yin; Lei He; Paul J. Harrison

2012-01-01

421

Original article Nutrient leaching from soil amended with apple waste  

E-print Network

Original article Nutrient leaching from soil amended with apple waste Anne-Marie de COCKBORNE December 2000) Abstract ­ Among the possibilities for disposing of overproduction of apple, land application is flexible and inexpensive. Six soil columns receiving 0, 200 or 500 Mg of apple wasteha­1 were

Paris-Sud XI, Université de

422

Primary Consumer Stable Nitrogen Isotopes as Indicators of Nutrient  

E-print Network

cause of eutrophication of inland waters, although the diffuse and variable nature of nutrient inputsDanishlakesspanningarangeoftrophicstates(oligotrophic to eutrophic) and land uses (forest, urban, agriculture). Primary consumer 15N values eutrophication of aquatic systems, with consequent algal blooms, fish kills, habitat and biodiversity loss

Vander Zanden, Jake

423

Nutrient removal from eutrophic lake water by wetland filtration  

Microsoft Academic Search

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

M. F. Coveney; D. L. Stites; E. F. Lowe; L. E. Battoe; R. Conrow

2002-01-01

424

Nutrient Management Module No. 8 Soil pH and  

E-print Network

H is a measure of the soil solution's acidity and alkalinity. By definition, pH is the `negative logarithm4449-8 May 2009 Nutrient Management Module No. 8 Soil pH and Organic Matter by Ann McCauley, Soil Scientist; Clain Jones, Extension Soil Fertility Specialist; and Jeff Jacobsen, College of Agriculture Dean

Lawrence, Rick L.

425

Nutrient content and in vitro digestibility of Turkish grape pomaces  

Microsoft Academic Search

During harvest of grapes for wine production in Turkey, a total of 28 fresh grape pomace samples from white and red wine grape varieties were collected from wine production facilities. Samples were classified by grape color and the pomace from red grapes was separated manually into stalk, skin plus pulp and seed fractions. Nutrient contents were determined for total samples

M. Basalan; T. Gungor; F. N. Owens; I. Yalcinkaya

2011-01-01

426

Climate Variability Impacts on Watershed Nutrient Delivery and Reservoir Production  

Microsoft Academic Search

Reservoirs in agricultural dominated watersheds tend to exhibit pulse-system behavior especially if located in climates dominated by summer convective precipitation inputs. Concentration and bulk mass of nutrient and sediment inputs into reservoir systems vary in terms of timing and magnitude of delivery from watershed sources to reservoirs under these climate conditions. Reservoir management often focuses on long-term average inputs without

J. D. White; S. J. Prochnow; L. M. Zygo; B. W. Byars

2005-01-01

427

DEVELOPMENT OF SAV LOSS-NUTRIENT LOAD RELATIONSHIPS  

EPA Science Inventory

The Nutrient Team effort related to SAV is comprised of two components. 1) collection of necessary data to determine the effectiveness of modeling SAV important to Gulf of Mexico estuarine environments; and 2) collaboration with the USGS wetland research center to analyze changes...

428

Nutrient Management Module No. 1 Soil Sampling and  

E-print Network

and/or soil amendments to optimize economic return. The objectives of this module are to: 1) describe samples that are representative of the field to be fertilized. If soil is submitted from only a fewNutrient Management Module No. 1 Soil Sampling and Laboratory Selection by Clain Jones, Soil

Lawrence, Rick L.

429

The Effect of Dexmedetomidine on Nutrient Organ Blood Flow  

Microsoft Academic Search

The cY,-adrenergic agonist dexmedetomidine decreases not only heart rate, myocardial contractility, and oxy- gen demand, but also cardiac output (Q). To investigate whether this reduction in Q could critically impair per- fusion of individual organs, we studied the effect of dexmedetomidine on nutrient blood flow to the heart, brain, kidney, spleen, skin, intestine, liver, and arterio- venous anastomoses using the

C. J. Lawrence; F. W. Prinzen; S. de Lange

1996-01-01

430

Plant Leaf Residue Decomposition, Nutrient Release and Soil Enzyme Activity  

Microsoft Academic Search

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

Julia Dux; Lindsey Norgrove; Stefan Hauser; Barbara Wick; Ronald Kühne

431

Urban Runoff and Nutrients Loading Control from Sustainable BMPs (Invited)  

Microsoft Academic Search

Climate change alters hydrodynamic and nutrient dynamic in both large and small geographic scales. These changes in our freshwater system directly affect drinking water, food production, business, and all aspects of our life. Along with climate change is increasing urbanization which alters natural landscape. Urban runoff has been identified as one of many potential drivers of the decline of pelagic

Q. Xiao

2009-01-01

432

Injection of nutrients and TEAs in clayey soils using electrokinetics  

SciTech Connect

Bioremediation is a cost-effective and attractive technique for cleanup of organic contaminants in high-permeable soils. Difficulties in providing sufficient nutrients and terminal electron acceptors (TEAs) (e.g., nitrate and sulfate) to subsurface contaminant locations preclude its use for in situ biodegradation of organic contaminants in clayey soils. Electrokinetics is shown to be an effective means to inject necessary ionic nutrients and TEAs in clayey soils. Theoretical analysis and experimental results show that electromigration is a significant factor compared with advective transport rate of ions by electroosmosis. Negatively charged nutrients and TEAs could be injected via introducing them at the cathode and vice versa for positively charged ions. Results also indicate that the concentration achievable in the soil depends on the conductivity of the soil and the inlet concentration of the ion to be injected. The higher the soil conductivity and the inlet concentration the higher is the concentration of ionic nutrients and TEAs achievable in the soil. The pH conditions in the soil could be maintained within the range of approximately 6--9 by placing a calcium carbonate layer in the vicinity of the anode.

Thevanayagam, S. [State Univ. of New York, Buffalo, NY (United States). Dept. of Civil, Structural, and Environmental Engineering; Rishindran, T. [Terraprobe, Brampton, Ontario (Canada)

1998-04-01

433

Morphological responses to nutrient availability in four clonal herbs  

Microsoft Academic Search

This paper examines morphological plasticity of clonal plants of contrasting habitats and of contrasting architectures in response to nutrient supply. The hypotheses were tested that plants from rich habitats possess greater plasticity in response to variation in resource supply than species from poor habitats, and that rhizomatous species are less plastic in their response than stoloniferous species. Two sympodial rhizomatous

Ming Dong; Marinus J. A. Werger

1996-01-01

434

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...

435

Enterectomy, vagal deafferentation and nutrient utilization in the pig  

E-print Network

NOTE Enterectomy, vagal deafferentation and nutrient utilization in the pig J.P. LAPLACE G to a total vagal deafferentation, or to a 4 m distal jejunectomy, or to both deafferentation and jejunectomy, 1980 a and 1981). These results were obtained in the Pig using vagal deafferentation (LAPLACE, 1980 b

Boyer, Edmond

436

Nutrient limitation and algal blooms in urbanizing tidal creeks  

Microsoft Academic Search

Tidal creeks are commonly found in low energy systems on the East and Gulf Coasts of the United States, and are often subject to intense watershed human development. Many of these creeks are receiving urban and suburban runoff containing nutrients, among other pollutants. During the period 1993–2001, we studied three tidal creeks located in southeastern North Carolina, a rapidly urbanizing

Michael A. Mallin; Douglas C. Parsons; Virginia L. Johnson; Matthew R. McIver; Heather A. CoVan

2004-01-01

437

Herbivores and nutrients control grassland plant diversity via light limitation.  

SciTech Connect

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.

Borer, Elizabeth T. [Department of Ecology, Evolution, and Behavior, University of Minnesota; et al, et al

2014-01-01

438

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...

439

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...

440

Microbial activity and nutrient dynamics in earthworm casts (Lumbricidae)  

Microsoft Academic Search

Microbial respiration, microbial biomass and nutrient requirements of the microflora (C, N, P) were studied in the food substrate (soil taken from the upper 3 cm of the mineral soil of a beech wood on limestone), the burrow walls and the casts of the earthworm Aporrectodea caliginosa (Savigny). The passage of the soil through the gut caused an increase in

S. Scheu

1987-01-01

441

Recovery of three arctic stream reaches from experimental nutrient enrichment  

USGS Publications Warehouse

1. Nutrient enrichment and resulting eutrophication is a widespread anthropogenic influence on freshwater ecosystems, but recovery from nutrient enrichment is poorly understood, especially in stream environments. We examined multi-year patterns in community recovery from experimental low-concentration nutrient enrichment (N + P or P only) in three reaches of two Arctic tundra streams (Kuparuk River and Oksrukuyik Creek) on the North Slope of Alaska (U.S.A.). 2. Rates of recovery varied among community components and depended on duration of enrichment (2-13 consecutive growing seasons). Biomass of epilithic algae returned to reference levels rapidly (within 2 years), regardless of nutrients added or enrichment duration. Aquatic bryophyte cover, which increased greatly in the Kuparuk River only after long-term enrichment (8 years), took 8 years of recovery to approach reference levels, after storms had scoured most remnant moss in the recovering reach. 3. Multi-year persistence of bryophytes in the Kuparuk River appeared to prevent recovery of insect populations that had either been positively (e.g. the mayfly Ephemerella, most chironomid midge taxa) or negatively (e.g. the tube-building chironomid Orthocladius rivulorum) affected by this shift in dominant primary producer. These lags in recovery (of >3 years) were probably driven by the persistent effect of bryophytes on physical benthic habitat. 4. Summer growth rates of Arctic grayling (both adults and young-of-year) in Oksrukuyik Creek (fertilised for 6 years with no bryophyte colonisation), which were consistently increased by nutrient addition, returned to reference rates within 1-2 years. 5. Rates of recovery of these virtually pristine Arctic stream ecosystems from low-level nutrient enrichment appeared to be controlled largely by duration of enrichment, mediated through physical habitat shifts caused by eventual bryophyte colonisation, and subsequent physical disturbance that removed bryophytes. Nutrient enrichment of oligotrophic Arctic stream ecosystems caused by climate change or local anthropogenic activity may have dramatic and persistent consequences if it results in the colonisation of long-lived primary producers that alter physical habitat. ?? 2007 The Authors.

Benstead, J.P.; Green, A.C.; Deegan, L.A.; Peterson, B.J.; Slavik, K.; Bowden, W.B.; Hershey, A.E.

2007-01-01

442

Nutrient Limitation of Microbial Mediated Decomposition and Arctic Soil Chronology  

NASA Astrophysics Data System (ADS)

Soils of northern permafrost regions currently contain twice as much carbon as the entire Earth's atmosphere. Traditionally, environmental constraints have limited microbial activity resulting in restricted decomposition of soil organic matter in these systems and accumulation of massive amounts of soil organic carbon (SOC), however climate change is reducing the constraints of decomposition in arctic permafrost regions. Carbon cycling in nutrient poor, arctic ecosystems is tightly coupled to other biogeochemical cycles. Several studies have suggested strong nitrogen limitations of primary productivity and potentially warm-season microbial activity in these nutrient deficient soils. Nitrogen is required for microbial extracellular enzyme production which drives the decomposition of soil organic matter (SOM). Nitrogen limited arctic soils may also experience limitation via labile carbon availability despite the SOM rich environment due to low extracellular enzyme production. Few studies have directly addressed nutrient induced microbial limitation in SOC rich arctic tundra soils, and even less is known about the potential for nutrient co-limitation. Additionally, through the process of becoming deglaciated, sites within close proximity to one another may have experienced drastic differences in their effective soil ages due to the varied length of their active histories. Many soil properties and nutrient deficiencies are directly related to soil age, however this chronology has not previously been a focus of research on nutrient limitation of arctic soil microbial activity. Understanding of nutrient limitations, as well as potential co-limitation, on arctic soil microbial activity has important implications for carbon cycling and the ultimate fate of the current arctic SOC reservoir. Analyses of nutrient limitation on soils of a single site are not adequate for fully understanding the controls on soil microbial activity across a vast land mass with large variation in effective soil age. My research is focused on addressing the questions of the extent of microbial N limitation in arctic tundra soils, the potential for co-limitation of labile C despite a high SOC environment, and the dependence, if any, nutrient limitation may have on the effective age of the soil. I have addressed these questions by conducting a laboratory soil incubation of factorial design with treatments of amended glucose, amended ammonium nitrate, and a control consisting of an addition of an equivalent volume of deionized water. Moist acid tundra soils possessing similar soil properties from two arctic sites of close proximity yet with varying deglaciation chronologies were utilized in my study. Soil properties of C-mineralization via respiration, microbial biomass, and nitrogen content in the forms of ammonium, nitrate, and total free amino acids and microbial extra-cellular enzyme production were assayed to determine the microbial response to the experimental treatments. Through the results of this work, I hope to better our understanding of biogeochemical cycling within arctic tundra ecosystems and the response to climate change by contributing to existing knowledge of nutrient limitation on microbial mediated decomposition of SOC in the arctic and how this may differ in soils of varying effective age.

Melle, C. J.; Darrouzet-Nardi, A.; Wallenstein, M. D.

2012-12-01

443

Plasticity of the Arabidopsis Root System under Nutrient Deficiencies1[C][W][OPEN  

PubMed Central

Plant roots show a particularly high variation in their morphological response to different nutrient deficiencies. Although such changes often determine the nutrient efficiency or stress tolerance of plants, it is surprising that a comprehensive and comparative analysis of root morphological responses to different nutrient deficiencies has not yet been conducted. Since one reason for this is an inherent difficulty in obtaining nutrient-deficient conditions in agar culture, we first identified conditions appropriate for producing nutrient-deficient plants on agar plates. Based on a careful selection of agar specifically for each nutrient being considered, we grew Arabidopsis (Arabidopsis thaliana) plants at four levels of deficiency for 12 nutrients and quantified seven root traits. In combination with measurements of biomass and elemental concentrations, we observed that the nutritional status and type of nutrient determined the extent and type of changes in root system architecture (RSA). The independent regulation of individual root traits further pointed to a differential sensitivity of root tissues to nutrient limitations. To capture the variation in RSA under different nutrient supplies, we used principal component analysis and developed a root plasticity chart representing the overall modulations in RSA under a given treatment. This systematic comparison of RSA responses to nutrient deficiencies provides a comprehensive view of the overall changes in root plasticity induced by the deficiency of single nutrients and provides a solid basis for the identification of nutrient-sensitive steps in the root developmental program. PMID:23852440

Gruber, Benjamin D.; Giehl, Ricardo F.H.; Friedel, Swetlana; von Wiren, Nicolaus

2013-01-01

444

Birds transport nutrients to fragmented forests in an urban landscape.  

PubMed

The influence of urbanization on nutrient cycling is vaguely known. Here we document that birds, especially those increasing in urban areas (such as crows, Corvus macrorhynchos and C. corone), affect nutrient cycles. Using fecal traps, we measured phosphorus (P) and nitrogen (N) input from the excrement of birds in fragmented forests in an urban landscape. Sources of avian feces were examined on the basis of carbon (C), N, and P percentages and stable isotopes of delta15N and delta13C. Nitrogen and P input was aggregated in the urban landscape, being especially high at the forest where crows roosted during winter. The annual P input due to bird droppings (range 0.068-0.460 kg x ha(-1) x yr(-1); mean 0.167 kg x ha(-1) x yr(-1)) was 12.4% of the total of other pathways in typical forests and 52.9% in the evergreen forest where crows roosted. The annual N input due to bird droppings (range 0.44-3.49 kg x ha(-1) x yr(-1); mean 1.15 kg x ha(-1) x yr(-1)) was 5.2% of the total of other pathways in typical forests and 27.0% in the evergreen forest used by roosting crows. Expected sources of nutrients in feces included insects in the breeding season, fruits in autumn, and mammals and birds in winter. Stable isotopes suggested that the source of nutrients in forests used by roosting crows was from outside the forest. Therefore, birds played a significant role as transporters of nutrients from garbage (including fish, livestock, and/or C4 plants such as corn, with high delta15N and delta13C) in residential and business areas to fragmented evergreen forests, especially near their winter roosts. PMID:17494385

Fujita, Motoko; Koike, Fumito

2007-04-01

445

MODEL SIMULATION STUDIES OF SCALE-DEPENDENT GAIN IN STREAM NUTRIENT ASSIMILATIVE CAPACITY RESULTING FROM IMPROVING NUTRIENT RETENTION METRICS  

EPA Science Inventory

Considering the difficulty in measuring restoration success for nonpoint source pollutants, nutrient assimilative capacity (NAS) offers an attractive systems-based metric. Here NAS was defined using an impulse-response model of nitrate fate and transport. Eleven parameters were e...

446

Table 1. Nutrient content of corn grain and stover at 150 bu/acre yield Nutrient Grain Stover Total  

E-print Network

for Field, Vegetable and Fruit Crops (A2809). If insufficient nutrients are avail- able to the corn plant planting dates, selection of adapted hybrids, and effective weed and insect control. This publication. Liming for corn production Aglime recommendations are based on the target pH level of the most acid

Balser, Teri C.

447

Effect of Temperature and Nutrient Manipulations on eelgrass Zostera marina L. from the Pacific Northwest, USA  

EPA Science Inventory

Global climate change will have a large impact on the three predominate drivers of estuarine seagrass productivity, temperature, light and nutrients. I experimentally evaluate the response of Pacific Northwest Z. marina to interactive effects of temperature and nutrient conditio...

448

9 CFR 317.369 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2013 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2013-01-01

449

9 CFR 317.369 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2012 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2012-01-01

450

9 CFR 381.469 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2010 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2010-01-01

451

9 CFR 381.469 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2013 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2013-01-01

452

9 CFR 381.469 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2012 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2012-01-01

453

9 CFR 317.369 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2011 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2011-01-01

454

9 CFR 317.369 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2010 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2010-01-01

455

9 CFR 381.469 - Labeling applications for nutrient content claims.  

Code of Federal Regulations, 2011 CFR

...following form to the Director, Food Labeling Division, Regulatory Programs, Food Safety and Inspection Service...level of the nutrient in the food would qualify the label of...regulation. Assay methods used to determine the level of a nutrient...

2011-01-01

456

NUTRIENT CONTAMINATION AS A RESULT OF POINT SOURCE DISCHARGES: A SURVEY  

EPA Science Inventory

Nutrients are common contaminants in Gulf of Mexico estuaries and when present in high concentrations, they can cause excessive algal growths and hypoxic conditions. The magnitude and biological significance of nutrient loading to estuarine waters receiving treated wastewaters is...

457

7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.  

...contamination of crops, soil, or water by plant nutrients, pathogenic organisms, heavy metals, or residues of prohibited...contamination of crops, soil, or water by plant nutrients, pathogenic organisms, heavy metals, or residues of...

2014-01-01

458

Regulating farm nutrient runoff : Maryland's experience with the Water Quality Improvement Act  

E-print Network

Federal and state programs designed to address nonpoint agricultural nutrient pollution rely almost exclusively on voluntary programs and financial incentives to encourage farmers to adopt nutrient management plans and ...

Herbst, Annemarie H

2005-01-01

459

HYDRAULIC FRACTURING TO IMPROVE NUTRIENT AND OXYGEN DELIVERY FOR IN SITU BIORECLAMATION  

EPA Science Inventory

The in situ delivery of nutrients and oxygen in soil is a serious problem in implementing in situ biodegradation. Current technology requires ideal site conditions to provide the remediating organisms with the nutrients and oxygen required for their metabolism, but...

460

COMMUNICATION: SHOULD ECOLOGICAL REGIONS OR LAND-COVER COMPOSITION GUIDE ESTABLISHMENT OF NUTRIENT CRITERIA?  

EPA Science Inventory

The continuing expansion of anthropogenic influence across the continental United States has motivated the establishment of nutrient criteria for streams, lakes, and estuaries as a means to promote the protection of aquatic resources. Nutrient criteria have been established based...

461

COMMUNICATION: SHOULD ECOLOGICAL REGIONS OR LAND-COVER COMPOSITION GUIDE ESTABLISHMENT OF NUTRIENT CRITERIA  

EPA Science Inventory

The continuing expansion of anthropogenic influence across the continental United States has motivated the establishment of nutrient criteria for streams, lakes, and estuaries as a means to promote the protection of aquatic resources. Nutrient criteria have been established base...

462

Evaluations of nutrient diffusing substrates and the primary importance of light in controlling periphyton  

E-print Network

eutrophication. In the first study, artificial channels were used to investigate the response of periphyton to different nutrient delivery mechanisms. In two channels, nutrients were delivered via diffusion to periphyton growth surfaces using modified Matlock...

Murawski, Matthew Thomas

2012-06-07

463

Geomorphic stream restoration as an approach for reducing nutrients in degraded urban watersheds  

EPA Science Inventory

Elevated nitrate levels in streams and groundwater pose human and ecological threats. Stream restoration may improve the nutrient removal capacity of streams, yet few studies have investigated the effectiveness of restoration as a nutrient BMP despite significant national effort...

464

78 FR 13874 - Watershed Modeling To Assess the Sensitivity of Streamflow, Nutrient, and Sediment Loads to...  

Federal Register 2010, 2011, 2012, 2013

...Nutrient, and Sediment Loads to Climate Change and Urban Development in 20 U...Nutrient, and Sediment Loads to Climate Change and Urban Development in 20 U...of plausible mid-21st century climate change and urban development...

2013-03-01