WorldWideScience

Sample records for plant nutrient mobilization

  1. Plant nutrient mobilization in temperate heathland responds to elevated CO2, temperature and drought

    DEFF Research Database (Denmark)

    Andresen, Louise C.; Michelsen, Anders; Jonasson, Sven

    2010-01-01

    when combined with CO2 and drought. Below Deschampsia, the net nitrification rate decreased in response to drought and, while phosphorus availability and microbial P immobilization decreased, but nitrification increased in response to elevated CO2. Furthermore, leaf litter decomposition of both species...... decreased in response to drought. These complex changes in availability and release of nutrients from soil organic matter turnover and mineralization in response to elevated CO2 and climate change may influence the future plant carbon sequestration and species composition at temperate heathlands....

  2. Reduction of soluble nitrogen and mobilization of plant nutrients in soils from U.S. northern Great Plains agroecosystems by phenolic compounds

    Science.gov (United States)

    Phenolic plant secondary metabolites actively participate in a broad range of important reactions that affect livestock, plants and soil. In soil, phenolic compounds can affect nutrient dynamics and mobility of metals but their role in northern Great Plains agroecosystems is largely unknown. We eval...

  3. Leaf-mining by Phyllonorycter blancardella reprograms the host-leaf transcriptome to modulate phytohormones associated with nutrient mobilization and plant defense.

    Science.gov (United States)

    Zhang, Hui; Dugé de Bernonville, Thomas; Body, Mélanie; Glevarec, Gaëlle; Reichelt, Michael; Unsicker, Sybille; Bruneau, Maryline; Renou, Jean-Pierre; Huguet, Elisabeth; Dubreuil, Géraldine; Giron, David

    2016-01-01

    Phytohormones have long been hypothesized to play a key role in the interactions between plant-manipulating organisms and their host-plants such as insect-plant interactions that lead to gall or 'green-islands' induction. However, mechanistic understanding of how phytohormones operate in these plant reconfigurations is lacking due to limited information on the molecular and biochemical phytohormonal modulation following attack by plant-manipulating insects. In an attempt to fill this gap, the present study provides an extensive characterization of how the leaf-miner Phyllonorycter blancardella modulates the major phytohormones and the transcriptional activity of plant cells in leaves of Malus domestica. We show here, that cytokinins strongly accumulate in mined tissues despite a weak expression of plant cytokinin-related genes. Leaf-mining is also associated with enhanced biosynthesis of jasmonic acid precursors but not the active form, a weak alteration of the salicylic acid pathway and a clear inhibition of the abscisic acid pathway. Our study consolidates previous results suggesting that insects may produce and deliver cytokinins to the plant as a strategy to manipulate the physiology of the leaf to create a favorable nutritional environment. We also demonstrate that leaf-mining by P. blancardella leads to a strong reprogramming of the plant phytohormonal balance associated with increased nutrient mobilization, inhibition of leaf senescence and mitigation of plant direct and indirect defense.

  4. Regulating nutrient allocation in plants

    Science.gov (United States)

    Udvardi, Michael; Yang, Jiading; Worley, Eric

    2014-12-09

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

  5. Regulating nutrient allocation in plants

    Energy Technology Data Exchange (ETDEWEB)

    Udvardi, Michael; Yang, Jiading; Worley, Eric

    2014-12-09

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

  6. Plant Mobile Small RNAs

    OpenAIRE

    Dunoyer, Patrice; Melnyk, Charles; Molnar, Attila; Slotkin, R Keith

    2013-01-01

    In plants, RNA silencing is a fundamental regulator of gene expression, heterochromatin formation, suppression of transposable elements, and defense against viruses. The sequence specificity of these processes relies on small noncoding RNA (sRNA) molecules. Although the spreading of RNA silencing across the plant has been recognized for nearly two decades, only recently have sRNAs been formally demonstrated as the mobile silencing signals. Here, we discuss the various types of mobile sRNA mol...

  7. Tree root systems and nutrient mobilization

    DEFF Research Database (Denmark)

    Boyle, Jim; Rob, Harrison; Raulund-Rasmussen, Karsten;

    Roots mobilize nutrients via deep penetration and rhizosphere processes inducing weathering of primary minerals. These contribute to C transfer to soils and to tree nutrition. Assessments of these characteristics and processes of root systems are important for understanding long-term supplies...... of nutrient elements essential for forest growth and resilience. Research and techniques have signifi cantly advanced since Olof Tamm’s 1934 base mineral index for Swedish forest soils, and basic nutrient budget estimates for whole-tree harvesting systems of the 1970s. Recent research in areas that include...... sometimes stored at depth. Other recent studies on potential release of nutrients due to chemical weathering indicate the importance of root access to deep soil layers. Release profi les clearly indicate depletion in the top layers and a much higher potential in B and C horizons. Review of evaluations...

  8. Plant Mobile Small RNAs

    Science.gov (United States)

    Dunoyer, Patrice; Melnyk, Charles; Molnar, Attila; Slotkin, R. Keith

    2013-01-01

    In plants, RNA silencing is a fundamental regulator of gene expression, heterochromatin formation, suppression of transposable elements, and defense against viruses. The sequence specificity of these processes relies on small noncoding RNA (sRNA) molecules. Although the spreading of RNA silencing across the plant has been recognized for nearly two decades, only recently have sRNAs been formally demonstrated as the mobile silencing signals. Here, we discuss the various types of mobile sRNA molecules, their short- and long-range movement, and their function in recipient cells. PMID:23818501

  9. Plant and pathogen nutrient acquisition strategies

    OpenAIRE

    Fatima, Urooj; Senthil-Kumar, Muthappa

    2015-01-01

    Nutrients are indispensable elements required for the growth of all living organisms including plants and pathogens. Phyllosphere, rhizosphere, apoplast, phloem, xylem, and cell organelles are the nutrient niches in plants that are the target of bacterial pathogens. Depending upon nutrients availability, the pathogen adapts various acquisition strategies and inhabits the specific niche. In this review, we discuss the nutrient composition of different niches in plants, the mechanisms involved ...

  10. Terrestrial plants require nutrients in similar proportions.

    Science.gov (United States)

    Knecht, Magnus F; Göransson, Anders

    2004-04-01

    Theoretical considerations based on nutrition experiments suggest that nutrient ratios of terrestrial plants are similar to the Redfield ratio found in marine phytoplankton. Laboratory experiments have shown that seedlings of many different plant species have similar nutrient concentration ratios when supplied with nutrients at free access. However, at free access, nutrients are likely to be taken up in amounts in excess of a plant's requirements for growth. In further experiments, therefore, the supply rate of each nutrient was reduced so that excessive uptake did not occur. Again, similar nutrient ratios were found among the plant species tested, although the ratios differed from those found in plants given free access to nutrients. Based on the law of the minimum, we suggest that optimum nutrient ratios be defined as the ratios found in plants when all nutrients are limiting growth simultaneously. The literature on nutrient concentrations was surveyed to investigate nutrient ratios in terrestrial ecosystems. Nutrients taken into consideration were nitrogen, phosphorus, potassium, calcium and magnesium. Based on the assumption that nitrogen is either the limiting nutrient or, when not limiting, is taken up only in small excess amounts, we calculated nutrient ratios from published data. The calculated ratios corresponded closely to the ratios determined in laboratory and field experiments.

  11. Plant nutrient transporter regulation in arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, Stephen; Bechmann, I.E.

    2002-01-01

    This review discusses the role arbuscular mycorrhizal fungi play in the regulation of plant nutrient transporter genes. Many plant nutrient transporter genes appear to be transcriptionally regulated by a feed-back mechanism that reduces their expression when the plant reaches an optimal level...

  12. Tree root systems and nutrient mobilization

    DEFF Research Database (Denmark)

    Boyle, Jim; Rob, Harrison; Raulund-Rasmussen, Karsten

    Roots mobilize nutrients via deep penetration and rhizosphere processes inducing weathering of primary minerals. These contribute to C transfer to soils and to tree nutrition. Assessments of these characteristics and processes of root systems are important for understanding long-term supplies...... some of the world’s most productive intensively managed forests, including Brazil and the Southeast and Pacifi c Northwest regions of the United States, have shown that root systems are often several meters in depth, and often extend deeper than soil is sampled. Large amounts of carbon are also...... sometimes stored at depth. Other recent studies on potential release of nutrients due to chemical weathering indicate the importance of root access to deep soil layers. Release profi les clearly indicate depletion in the top layers and a much higher potential in B and C horizons. Review of evaluations...

  13. Microbial phosphorous mobilization strategies across a natural nutrient limitation gradient

    Science.gov (United States)

    Walker, R.; Wang, S.; Nico, P. S.; Fox, P. M.; Hao, Z.; Karaoz, U.; Torok, T.; Brodie, E.; Chakraborty, R.; Hao, Z.

    2016-12-01

    Phosphorus (P) is a critical nutrient and frequently limits primary productivity in terrestrial ecosystems. Microorganisms have evolved an array of strategies to mobilize occluded and insoluble P and may be important regulators of P availability to vegetation. Understanding the mechanisms of P mobilization, the breadth of microorganisms responsible, and the impact of these organisms on vegetation growth remains an important knowledge gap for both predicting ecosystem productivity and harnessing microbial functions to improve vegetation growth. To determine the relationship between soil development, phosphorus availability and P mobilizing microorganisms and their strategies we are studying a marine terrace chronosequence (Ecological Staircase, Mendocino County, CA) representing a fertility gradient culminating in P-limited pygmy forests that provide an ideal natural observatory to investigate how plant-microbe interactions co-evolve in response to P stress. Soil mineralogical analysis identified acidic soils bearing iron and aluminum phosphates and phytate as the dominant forms of occluded inorganic and organic P, respectively. Several diverse bacterial and fungal strains were isolated on media with AlPO4, FePO4, or phytate as the sole P source. Most microorganisms were able to utilize AlPO4 as a sole P source, with fewer subsisting on FePO4 or phytate. Terraces with a higher fraction of occluded and organic P harbored the greatest abundance of P-mobilizing microorganisms, with a significant proportion coming from the Burkholderia. Isolates that exhibited significant excess P mobilization were inoculated with Arabidopsis and Switchgrass plants grown with insoluble P forms had a positive impact on growth. These results indicate that rhizosphere microorganisms that have evolved under extreme nutrient limitation have an extended capacity for P solubilization, and could potentially be harnessed to alleviate P stress for plants. The detailed mechanisms for P

  14. Plant and pathogen nutrient acquisition strategies

    Directory of Open Access Journals (Sweden)

    Urooj eFatima

    2015-09-01

    Full Text Available Nutrients are indispensable elements required for the growth of all living organisms including plants and pathogens. Phyllosphere, rhizosphere, apoplast, phloem, xylem and cell organelles are the nutrient niches in plants that are the target of bacterial pathogens. Depending upon nutrients availability, the pathogen adapts various acquisition strategies and inhabits the specific niche. In this review, we discuss the nutrient composition of different niches in plants, the mechanisms involved in the recognition of nutrient niche and the sophisticated strategies used by the bacterial pathogens for acquiring nutrients. We provide insight into various nutrient acquisition strategies used by necrotrophic, biotrophic and hemi-biotrophic bacteria. Specifically we discuss both modulation of bacterial machinery and manipulation of host machinery. In addition, we highlight the current status of our understanding about the nutrient acquisition strategies used by bacterial pathogens, namely targeting the sugar transporters that are dedicated for the plant’s growth and development. Bacterial strategies for altering the plant cell membrane permeability to enhance the release of nutrients are also enumerated along with in-depth analysis of molecular mechanisms behind these strategies. The information presented in this review will be useful to understand the plant-pathogen interaction in nutrient perspective.

  15. Phloem small RNAs, nutrient stress responses, and systemic mobility

    Directory of Open Access Journals (Sweden)

    Kehr Julia

    2010-04-01

    Full Text Available Abstract Background Nutrient availabilities and needs have to be tightly coordinated between organs to ensure a balance between uptake and consumption for metabolism, growth, and defense reactions. Since plants often have to grow in environments with sub-optimal nutrient availability, a fine tuning is vital. To achieve this, information has to flow cell-to-cell and over long-distance via xylem and phloem. Recently, specific miRNAs emerged as a new type of regulating molecules during stress and nutrient deficiency responses, and miR399 was suggested to be a phloem-mobile long-distance signal involved in the phosphate starvation response. Results We used miRNA microarrays containing all known plant miRNAs and a set of unknown small (s RNAs earlier cloned from Brassica phloem sap 1, to comprehensively analyze the phloem response to nutrient deficiency by removing sulfate, copper or iron, respectively, from the growth medium. We show that phloem sap contains a specific set of sRNAs that is distinct from leaves and roots, and that the phloem also responds specifically to stress. Upon S and Cu deficiencies phloem sap reacts with an increase of the same miRNAs that were earlier characterized in other tissues, while no clear positive response to -Fe was observed. However, -Fe led to a reduction of Cu- and P-responsive miRNAs. We further demonstrate that under nutrient starvation miR399 and miR395 can be translocated through graft unions from wild type scions to rootstocks of the miRNA processing hen1-1 mutant. In contrast, miR171 was not transported. Translocation of miR395 led to a down-regulation of one of its targets in rootstocks, suggesting that this transport is of functional relevance, and that miR395, in addition to the well characterized miR399, could potentially act as a long-distance information transmitter. Conclusions Phloem sap contains a specific set of sRNAs, of which some specifically accumulate in response to nutrient deprivation. From

  16. Plant Watering Autonomous Mobile Robot

    National Research Council Canada - National Science Library

    Hema Nagaraja; Reema Aswani; Monisha Malik

    2012-01-01

    .... The system comprises of a mobile robot and a temperature-humidity sensing module. The system is fully adaptive to any environment and takes into account the watering needs of the plants using the temperature-humidity sensing module...

  17. Plant Watering Autonomous Mobile Robot

    Directory of Open Access Journals (Sweden)

    Hema Nagaraja

    2012-07-01

    Full Text Available Now days, due to busy routine life, people forget to water their plants. In this paper, we present a completely autonomous and a cost-effective system for watering indoor potted plants placed on an even surface. The system comprises of a mobile robot and a temperature-humidity sensing module. The system is fully adaptive to any environment and takes into account the watering needs of the plants using the temperature-humidity sensing module. The paper describes the hardware architecture of the fully automated watering system, which uses wireless communication to communicate between the mobile robot and the sensing module. This gardening robot is completely portable and is equipped with a Radio Frequency Identification (RFID module, a microcontroller, an on-board water reservoir and an attached water pump. It is capable of sensing the watering needs of the plants, locating them and finally watering them autonomously without any human intervention. Mobilization of the robot to the potted plant is achieved by using a predefined path. For identification, an RFID tag is attached to each potted plant. The paper also discusses the detailed implementation of the system supported with complete circuitry. Finally, the paper concludes with system performance including the analysis of the water carrying capacity and time requirements to water a set of plants.

  18. Endocytotic uptake of nutrients in carnivorous plants.

    Science.gov (United States)

    Adlassnig, Wolfram; Koller-Peroutka, Marianne; Bauer, Sonja; Koshkin, Edith; Lendl, Thomas; Lichtscheidl, Irene K

    2012-07-01

    Carnivorous plants trap, digest and absorb animals in order to supplement their mineral nutrition. Nutrients absorbed by the plant include different nitrogen species, phosphate, potassium, trace elements and small organic compounds. Uptake is usually thought to be performed via specific channels, but this study provides evidence that endocytosis is involved as well. Traps of the carnivorous plants Nepenthes coccinea, Nepenthes ventrata, Cephalotus follicularis, Drosophyllum lusitanicum, Drosera capensis, Dionaea muscipula, Aldrovanda vesiculosa, Genlisea violacea × lobata, Sarracenia psittacina and Sarracenia purpurea were stained with methylene blue in order to identify possible sites of uptake. The permeable parts of the traps were incubated with fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) and other fluorescent endocytosis markers, combined with the soluble protein BSA or respiratory inhibitors. Uptake was studied by confocal microscopy. In Nepenthes, small fluorescent vesicles became visible 1 h after incubation with FITC-BSA. These vesicles fused to larger compartments within 30 h. A similar behaviour was found in the related genera Drosera, Dionaea, Aldrovanda and Drosophyllum but also in Cephalotus with glands of different evolutionary origin. In Genlisea and Sarracenia, no evidence for endocytosis was found. We propose that in many carnivorous plants, nutrient uptake by carriers is supplemented by endocytosis, which enables absorption and intracellular digestion of whole proteins. The advantage for the plant of reducing secretion of enzymes for extracellular digestion is evident. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  19. Nutrient Use Efficiency in Plants: Concepts and Approaches

    NARCIS (Netherlands)

    Hawkesford, M.J.; Kopriva, S.; De Kok, L.J.

    2014-01-01

    Nutrient Use Efficiency in Plants: Concepts and Approaches is the ninth volume in the Plant Ecophysiology series. It presents a broad overview of topics related to improvement of nutrient use efficiency of crops. Nutrient use efficiency (NUE) is a measure of how well plants use the available mineral

  20. Negative effects of fertilization on plant nutrient resorption.

    Science.gov (United States)

    Yuan, Z Y; Chen, Han Y H

    2015-02-01

    Plants in infertile habitats are thought to have a high rate of nutrient resorption to enable them reuse nutrients more efficiently than those in fertile habitats. However, there is still much debate on how plant nutrient resorption responds to nutrient availability. Here we used a meta-analysis from a global data set of 9703 observations at 306 sites from 508 published articles to examine the effects of nitrogen (N) and phosphorus (P) fertilization on plant foliar N and P concentrations and resorption efficiency. We found that N fertilization enhanced N concentration in green leaves by 27% and P fertilization enhanced green-leaf P by 73% on average. The N and P concentrations in senesced leaves also increased with respective nutrient fertilization. Resorption efficiencies (percentage of nutrient recovered from senescing leaves) of both N and P declined in response to respective nutrient fertilization. Combined N and P fertilization also had negative effects on both N and P resorption efficiencies. Whether nutrient resorption efficiency differs among plant growth types and among ecosystems, however, remains uncertain due to the limited sample sizes when analyzed by plant growth types or ecosystem types. Our analysis indicates that fertilization decreases plant nutrient resorption and the view that nutrient resorption is a critical nutrient conservation strategy for plants in nutrient-poor environments cannot be abandoned. The response values to fertilization presented in our analysis can help improve biogeochemical models.

  1. Shoot Apex Demand Determines Assimilate and Nutrients Partitioning and Nutrient-uptake Rate in Tobacco Plants

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Our previous experiment revealed that apex-removed plants have larger root systems but a lower K+-uptake rates than intact tobacco plants.Since the apex is not only e center of growth and metabolism,but also an important place of auxin synthesis and export,the aims of this study were to distinguish whether the apex demand or auxin synthesized in the apex regulates assimilate and nutrients partitioning within plant,and to explain the reason for the lower K+-uptake rate of the apex-ramoved plant.In comparison with the control plant,covering the shoot apex with a black transparent plastic bag reduced net increases In dry matter and nutrients;however,the distribution of the dry matter and nutrients between shoot and roots and nutrient-uptake rates were not changed.Removal of the shoot apex shifted the dry mass and nutrients distributions to roots,and reduced the rate of nutrient uptake.Application of 1-naphthylacetic acid(NAA) could partly replace the role of the removed apex,stimulated assimilate and nutrient deposition into the treated tissue,and enhanced the reduced plasma membrane ATPase activity of roots to the control level.However,treatment of the apex-removed plants with NAA could not rescue the reduced nutrient uptake rate and the shifted assimilates and nutrients partitioning caused by excision of the apex.Higher nutrient uptake rate of the intact plants could not be explained by root growth parameters,such as total root surface area and number of root tips.The results from the present study indicate that strong apex demand determined assimilatas and nutrients partitioning and nutrient-uptake rate in tobacco(Nicotiana tabacum)plants.

  2. Biotechnology of nutrient uptake and assimilation in plants.

    Science.gov (United States)

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

    2013-01-01

    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.

  3. Phosphorus mobilizing consortium Mammoth P™ enhances plant growth

    Directory of Open Access Journals (Sweden)

    Peter Baas

    2016-06-01

    Full Text Available Phosphorus (P is a critical nutrient used to maximize plant growth and yield. Current agriculture management practices commonly experience low plant P use efficiency due to natural chemical sorption and transformations when P fertilizer is applied to soils. A perplexing challenge facing agriculture production is finding sustainable solutions to deliver P more efficiently to plants. Using prescribed applications of specific soil microbial assemblages to mobilize soil bound—P to improve crop nutrient uptake and productivity has rarely been employed. We investigated whether inoculation of soils with a bacterial consortium developed to mobilize soil P, named Mammoth PTM, could increase plant productivity. In turf, herbs, and fruits, the combination of conventional inorganic fertilizer combined with Mammoth PTM increased productivity up to twofold compared to the fertilizer treatments without the Mammoth PTM inoculant. Jalapeño plants were found to bloom more rapidly when treated with either Mammoth P. In wheat trials, we found that Mammoth PTM by itself was able to deliver yields equivalent to those achieved with conventional inorganic fertilizer applications and improved productivity more than another biostimulant product. Results from this study indicate the substantial potential of Mammoth PTM to enhance plant growth and crop productivity.

  4. Nutrient allocation among stem, leaf and inflorescence of jatropha plants

    Directory of Open Access Journals (Sweden)

    Rosiane L. S. de Lima

    2015-08-01

    Full Text Available ABSTRACTInformation on the partitioning of nutrients among various organs in jatropha plants, as a complementary tool for the recommendation of fertilization, is still not available. This study aimed to evaluate the contents of macro and micronutrients in stems, leaves and inflorescences of jatropha branches at the beginning of flowering. At the beginning of flowering, adult jatropha plants were sampled and divided into five compartments: inflorescences, leaves from vegetative branches, leaves from flowering branches, stems from vegetative branches and stems from flowering branches. Jatropha inflorescences are a drain of nutrients. Leaves are important sources of nutrients demanded by the inflorescences at the beginning of flowering. The higher allocation of nutrients in the inflorescences suggests the need for preventive/corrective fertilizations, which must be performed at least 30 days before flowering, providing plants with nutrients in adequate amounts for a good yield.

  5. White root tips supply plants with oxygen, water and nutrients

    NARCIS (Netherlands)

    Heuvelink, E.; Kierkels, T.

    2016-01-01

    The main, most important function of roots belonging to horticultural crops is the uptake of water and nutrients. Healthy roots are essential for a healthy plant. After all, if the uptake of water and nutrients is not functioning properly, then other aspects also leave a lot to be desired

  6. Salinization Enhances Mobilization of Nutrients from Sediments to Streams

    Science.gov (United States)

    Haq, S.; Kaushal, S.; Hohman, S.; Coplin, J.; Duan, S.

    2015-12-01

    Many regions of the U.S. and elsewhere are experiencing increased salinization of freshwater due to the widespread application of road salts. Increased salinization has the potential to release stored nutrients from sediments, decrease biodiversity, and perturb water quality. We conducted laboratory experiments to investigate the potential effects of road salt (NaCl) on nutrient mobilization from sediments to stream water. Sediments and stream water were incubated from 2 urbanizing watersheds of the Chesapeake Bay in the Baltimore-Washington Metropolitan area. Stream sediment was incubated from 11 routinely monitored streams exhibiting a land use gradient within the Baltimore Ecosystem Study Long-Term Ecological Research (BES LTER) site and Anacostia River watershed. Our results indicate that salinization increased the release of soluble reactive phosphorus and total dissolved nitrogen at all sites. The release of dissolved organic carbon and dissolved inorganic carbon varied between sites, and these differential responses may be due to: stream sediment composition, organic matter content, and ambient water quality. The magnitude and frequency of road salt application may be amplified in the near future due to the interactive effects of climate variability and urbanization, and our research suggests this can have water quality and ecological implications for freshwater ecosystems. Further research is necessary to elucidate driving mechanisms of changes in sediment biogeochemical cycles in response to salinization and the temporal response of freshwater ecosystems.

  7. Plant nutrients do not covary with soil nutrients under changing climatic conditions

    Science.gov (United States)

    Luo, Wentao; Elser, James J.; Lü, Xiao-Tao; Wang, Zhengwen; Bai, Edith; Yan, Caifeng; Wang, Chao; Li, Mai-He; Zimmermann, Niklaus E.; Han, Xingguo; Xu, Zhuwen; Li, Hui; Wu, Yunna; Jiang, Yong

    2015-08-01

    Nitrogen (N) and phosphorus (P) play vital roles in plant growth and development. Yet how climate regimes and soil fertility influence plant N and P stoichiometry is not well understood, especially in the belowground plant parts. Here we investigated plant aboveground and belowground N and P concentrations ([N] and [P]) and their stoichiometry in three dominant genera along a 2200 km long climatic gradient in northern China. Results showed that temperature explained more variation of [N] and [P] in C4 plants, whereas precipitation exerted a stronger influence on [N] and [P] in C3 plants. Both plant aboveground and belowground [N] and [P] increased with decreasing precipitation, and increasing temperatures yet were negatively correlated with soil [N] and [P]. Plant N:P ratios were unrelated with all climate and soil variables. Plant aboveground and belowground [N] followed an allometric scaling relationship, but the allocation of [P] was isometric. These results imply that internal processes stabilize plant N:P ratios and hence tissue N:P ratios may not be an effective parameter for predicting plant nutrient limitation. Our results also imply that past positive relationships between plant and nutrient stocks may be challenged under changing climatic conditions. While any modeling would need to be able to replicate currently observed relationships, it is conceivable that some relationships, such as those between temperature or rainfall and carbon:nutrient ratios, should be different under changing climatic conditions.

  8. Fire alters ecosystem carbon and nutrients but not plant nutrient stoichiometry or composition in tropical savanna.

    Science.gov (United States)

    Pellegrini, Adam F A; Hedin, Lars O; Staver, A Carla; Govender, Navashni

    2015-05-01

    Fire and nutrients interact to influence the global distribution and dynamics of the savanna biome, but the results of these interactions are both complex and poorly known. A critical but unresolved question is whether short-term losses of carbon and nutrients caused by fire can trigger long-term and potentially compensatory responses in the nutrient stoichiometry of plants, or in the abundance of dinitrogen-fixing trees. There is disagreement in the literature about the potential role of fire on savanna nutrients, and, in turn, on plant stoichiometry and composition. A major limitation has been the lack of fire manipulations over time scales sufficiently long for these interactions to emerge. We use a 58-year, replicated, large-scale, fire manipulation experiment in Kruger National Park (South Africa) in savanna to quantify the effect of fire on (1) distributions of carbon, nitrogen, and phosphorus at the ecosystem scale; (2) carbon: nitrogen: phosphorus stoichiometry of above- and belowground tissues of plant species; and (3) abundance of plant functional groups including nitrogen fixers. Our results show dramatic effects of fire on the relative distribution of nutrients in soils, but that individual plant stoichiometry and plant community composition remained unexpectedly resilient. Moreover, measures of nutrients and carbon stable isotopes allowed us to discount the role of tree cover change in favor of the turnover of herbaceous biomass as the primary mechanism that mediates a transition from low to high 'soil carbon and nutrients in the absence of fire. We conclude that, in contrast to extra-tropical grasslands or closed-canopy forests, vegetation in the savanna biome may be uniquely adapted to nutrient losses caused by recurring fire.

  9. Nutrient acquisition and secondary metabolites in plant pathogenic fungi

    DEFF Research Database (Denmark)

    Droce, Aida

    and infection processes of these two distinct phytopathogens are described with special attention on the importance of uptake and reallocation of nutrients. Nutrient uptake from host plant is crucial for fungi to grow and proliferate and during several developmental processes nutrient reallocation, a mechanism...... called autophagy, is crucial. In this ph.d project autophagy and dipeptide transport in Fg and Bgh is assessed with respect to pathology, developmental processes and mycotoxins production. Several techniques within molecular biology, bioinformatics, microbiology, analytical chemistry and plant pathology...

  10. Plant response to nutrient availability across variable bedrock geologies

    Science.gov (United States)

    Castle, S.C.; Neff, J.C.

    2009-01-01

    We investigated the role of rock-derived mineral nutrient availability on the nutrient dynamics of overlying forest communities (Populus tremuloides and Picea engelmanni-Abies lasiocarpa v. arizonica) across three parent materials (andesite, limestone, and sandstone) in the southern Rocky Mountains of Colorado. Broad geochemical differences were observed between bedrock materials; however, bulk soil chemistries were remarkably similar between the three different sites. In contrast, soil nutrient pools were considerably different, particularly for P, Ca, and Mg concentrations. Despite variations in nutrient stocks and nutrient availability in soils, we observed relatively inflexible foliar concentrations and foliar stoichiometries for both deciduous and coniferous species. Foliar nutrient resorption (P and K) in the deciduous species followed patterns of nutrient content across substrate types, with higher resorption corresponding to lower bedrock concentrations. Work presented here indicates a complex plant response to available soil nutrients, wherein plant nutrient use compensates for variations in supply gradients and results in the maintenance of a narrow range in foliar stoichiometry. ?? 2008 Springer Science+Business Media, LLC.

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

    Science.gov (United States)

    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 Ingman; Davies, Kendi F.; DeCrappeo, Nicole M.; Du, Guozhen; Firn, Jennifer; Hautier, Yann; Heckman, Robert W.; Hector, Andy; HilleRisLambers, Janneke; Iribarne, Oscar; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Leakey, Andrew D.B.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Mortensen, Brent; O'Halloran, Lydia R.; Orrock, John L.; Pascual, Jesús; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Williams, Ryan J.; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

    2014-01-01

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

  12. Nuclear power plants for mobile applications

    Science.gov (United States)

    Anderson, J. L.

    1972-01-01

    Mobile nuclear powerplants for applications other than large ships and submarines will require compact, lightweight reactors with especially stringent impact-safety design. The technical and economic feasibility that the broadening role of civilian nuclear power, in general, (land-based nuclear electric generating plants and nuclear ships) can extend to lightweight, safe mobile nuclear powerplants are examined. The paper discusses technical experience, identifies potential sources of technology for advanced concepts, cites the results of economic studies of mobile nuclear powerplants, and surveys future technical capabilities needed by examining the current use and projected needs for vehicles, machines, and habitats that could effectively use mobile nuclear reactor powerplants.

  13. [Interactive effects between plant allelochemicals, plant allelopathic potential and soil nutrients].

    Science.gov (United States)

    Xiao, Huilin; Peng, Shaolin; Zheng, Yuji; Mo, Jiangming; Luo, Wei; Zeng, Xiaoduo; He, Xiaoxia

    2006-09-01

    Plant allelopathy relates to many ecological factors. The deficit of soil nutrients can influence the production of plant allelochemicals, and thus, influence plant allelopathic potential, while plant allelochemicals can influence the form and level of soil nutrients by the ways of complexation, adsorption, acid dissolution, competition, inhibition, and others. In this paper, the interactive effects between plant allelochemicals, plant allelopathic potential and soil nutrients were summarized, and further research aspects in this field were prospected. It was suggested that following aspects should be strengthened: (1) the integration of plant allelopathy and soil-plant nutrition research to more precisely and deeply interpret the relationships between plant allelochemicals, plant allelopathic potential and soil nutrients, (2) the integration of plant allelopathy and ecosystem nutrient cycling research to simulate the plant nutrients disturbance in nature and make the allelopathy research results more true and more reliable, and (3) the allelopathy research with soils containing excessive nutrients or polluted to provide new ideas and scientific basis in revealing the mechanisms of plants interaction and biomass variation in agricultural and forestry production, and in ecological protection.

  14. Plant Leachate Nutrient Recovery with Biological, Thermal, and Photocatalytic Pretreatments

    Science.gov (United States)

    Wong, Les

    2015-01-01

    Plants are ideal for long term space travel: provide essential resources - oxygen, water, food; Water-soaked plants expel soluble nutrients in a leachate solution - toxins and wastes are also expelled and inhibit growth; biological, thermal, photocatalytic coupled with an acid digestion treatment will hopefully maximize recovery and remove wastes

  15. New Ways to Determine Plant Nutrient Deficiences Using Fast Spectroscopy

    DEFF Research Database (Denmark)

    van Maarschalkerweerd, Marie

    for soil and plant analysis are described and the usability of each technique is discussed. Focus is put particularly on the newest methods for plant analysis based on fast spectroscopy, such as visual and near-infrared (Vis-NIR) reflectance and chlorophyll a fluorescence. These methods enable easy, fast...... of measuring chlorophyll a fluorescence, gradually straightens and disappears as P deficiency is induced, and this is used in the method. A similar change was found in tomato plants, indicating that this could be a general effect on photosynthesis. There are further indications that also deficiencies of Mg, Cu...... used methods. Such instruments can help plant producers by optimizing nutrient addition of Cu and P, and there are clear indications that similar methods for further nutrients can be identified, to the benefit of agriculture as well as environment....

  16. Benchmarking Biological Nutrient Removal in Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Gernaey, Krist; Jeppsson, Ulf

    2011-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant...

  17. Modelling of the Nutrient Medium for Plants Cultivation in Spaceflight

    Science.gov (United States)

    Nechitailo, Galina S.

    2016-07-01

    MODELLING OF THE NUTRIENT MEDIUM FOR PLANTS CULTIVATION IN SPACEFLIGHT Nechitajlo G.S.*, Rakhmetova A.A.**, Bogoslovskaja O.A.**, Ol'hovskay I.P.**, Glushchenko N.N.** *Emanuel Institute of Biochemical Physics of Russian Academy of Sciences (IBCP RAS) mail: spacemal@mail.ru **V.L. Talrose Institute for Energy Problems of Chemical Physics of Russian Academy of Science (INEPCP RAS) mail: nnglu@ mail.ru The valuable life and fruitful activity of cosmonauts and researchers in conditions of spaceflights and prolonged work at space stations are only possible with creating life area providing fresh air, natural food, comfortable psychological conditions, etc. The solution of that problem under space conditions seems impossible without use of high nano- and biotechnologies for plants growth. A priority should be given not only to choose species of growth plants in space, but also to improve conditions for their growth which includes optimal nourishing components for plants, preparation of nutrient mediums, illumination and temperature. We are deeply convinced that just manipulations with growing conditions for cultivated plants, but not genes changes, is a guarantee of success in the decision of this problem. For improving the method of plants growing on the artificial nutrient medium with balanced content of components, being necessary for growth and development of plants, we added essential metal elements: Fe, Zn, Cu - in an electroneutral state in the form of nanoparticles instead of sulfates or other easily dissolving salts. Nanoparticulated metals are known to have a number of advantages in comparison with salts: metals in an electroneutral form are characterized with the prolonged and multifunctional action, low toxicity per se and appearing to be much below the toxicity of the same metals in the ionic forms, accumulation as a reserve being used in biotic dozes, active distribution in bodies and organs of plants and stimulation of vital processes. A high reactivity

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-01

    Human alterations to nutrient cycles1,2 and herbivore communities3–7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8,9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  19. Response of plant nutrient stoichiometry to fertilization varied with plant tissues in a tropical forest.

    Science.gov (United States)

    Mo, Qifeng; Zou, Bi; Li, Yingwen; Chen, Yao; Zhang, Weixin; Mao, Rong; Ding, Yongzhen; Wang, Jun; Lu, Xiankai; Li, Xiaobo; Tang, Jianwu; Li, Zhian; Wang, Faming

    2015-09-29

    Plant N:P ratios are widely used as indices of nutrient limitation in terrestrial ecosystems, but the response of these metrics in different plant tissues to altered N and P availability and their interactions remains largely unclear. We evaluated changes in N and P concentrations, N:P ratios of new leaves (1 yr), stems and mixed fine roots of seven species after 3-years of an N and P addition experiment in a tropical forest. Nitrogen addition only increased fine root N concentrations. P addition increased P concentrations among all tissues. The N × P interaction reduced leaf and stem P concentrations, suggesting a negative effect of N addition on P concentrations under P addition. The reliability of using nutrient ratios as indices of soil nutrient availability varied with tissues: the stoichiometric metrics of stems and older leaves were more responsive indicators of changed soil nutrient availability than those of new leaves and fine roots. However, leaf N:P ratios can be a useful indicator of inter-specific variation in plant response to nutrients availability. This study suggests that older leaf is a better choice than other tissues in the assessment of soil nutrient status and predicting plant response to altered nutrients using nutrients ratios.

  20. Chlorophyll Meters Aid Plant Nutrient Management

    Science.gov (United States)

    2009-01-01

    On December 7, 1972, roughly 5 hours and 6 minutes after launch, the crew of Apollo 17 took one of history s most famous photographs. The brilliant image of the fully illuminated Earth, the African and Antarctic continents peering out from behind swirling clouds, came to be known as the Blue Marble. Today, Earth still sometimes goes by the Blue Marble nickname, but as the satellites comprising NASA s Earth Observing System (EOS) scan the planet daily in ever greater resolutions, it is often the amount of green on the planet that is a focus of researchers attention. Earth s over 400,000 known plant species play essential roles in the planet s health: They absorb carbon dioxide and release the oxygen we breathe, help manage the Earth s temperature by absorbing and reflecting sunlight, provide food and habitats for animals, and offer building materials, medication, and sustenance for humans. As part of NASA s efforts to study our own planet along with the universe around it, the Agency s EOS satellites have been accumulating years of valuable data about Earth s vegetation (not to mention its land features, oceans, and atmosphere) since the first EOS satellite launched in 1997. Among the powerful sensors used is the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the NASA Terra and Aqua satellites. MODIS sweeps the entire Earth every few days, beaming back information gathered across 36 bands of visible and infrared light, yielding images that let scientists track how much of Earth is green over the course of seasons and years. Monitoring the density and distribution of vegetation on Earth provides a means of determining everything from the impact of natural and human-induced climate change to the potential outbreak of disease. (Goddard Space Flight Center and U.S. Department of Defense researchers have determined, for example, that vegetation density can be used to pinpoint regions of heavy rainfall in Africa regions ripe for outbreaks of rainfall

  1. Impact of Temperature and Nutrients on Carbon: Nutrient Tissue Stoichiometry of Submerged Aquatic Plants: An Experiment and Meta-Analysis.

    Science.gov (United States)

    Velthuis, Mandy; van Deelen, Emma; van Donk, Ellen; Zhang, Peiyu; Bakker, Elisabeth S

    2017-01-01

    Human activity is currently changing our environment rapidly, with predicted temperature increases of 1-5°C over the coming century and increased nitrogen and phosphorus inputs in aquatic ecosystems. In the shallow parts of these ecosystems, submerged aquatic plants enhance water clarity by resource competition with phytoplankton, provide habitat, and serve as a food source for other organisms. The carbon:nutrient stoichiometry of submerged aquatic plants can be affected by changes in both temperature and nutrient availability. We hypothesized that elevated temperature leads to higher carbon:nutrient ratios through enhanced nutrient-use efficiency, while nutrient addition leads to lower carbon:nutrient ratios by the luxurious uptake of nutrients. We addressed these hypotheses with an experimental and a meta-analytical approach. We performed a full-factorial microcosm experiment with the freshwater plant Elodea nuttallii grown at 10, 15, 20, and 25°C on sediment consisting of pond soil/sand mixtures with 100, 50, 25, and 12.5% pond soil. To address the effect of climatic warming and nutrient addition on the carbon:nutrient stoichiometry of submerged freshwater and marine plants we performed a meta-analysis on experimental studies that elevated temperature and/or added nutrients (nitrogen and phosphorus). In the microcosm experiment, C:N ratios of Elodea nuttallii decreased with increasing temperature, and this effect was most pronounced at intermediate nutrient availability. Furthermore, higher nutrient availability led to decreased aboveground C:P ratios. In the meta-analysis, nutrient addition led to a 25, 22, and 16% reduction in aboveground C:N and C:P ratios and belowground C:N ratios, accompanied with increased N content. No consistent effect of elevated temperature on plant stoichiometry could be observed, as very few studies were found on this topic and contrasting results were reported. We conclude that while nutrient addition consistently leads to

  2. Carbon storage and nutrient mobilization from soil minerals by deep roots and rhizospheres

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Harrison, Robert; Stupak, Inge

    2016-01-01

    Roots mobilize nutrients via deep soil penetration and rhizosphere processes inducing weathering of primary minerals. These processes contribute to C transfer to soils and to tree nutrition. Assessments of these characteristics and processes of root systems are important for understanding long...... studies on potential release of nutrients due to chemical weathering indicate the importance of root access to deep soil layers. Nutrient release profiles clearly indicate depletion in the top layers and a much higher potential in B and C horizons. Reviewing potential sustainability of nutrient supplies......-term supplies of nutrient elements essential for forest growth and resilience. Research and techniques have significantly advanced since Olof Tamm’s 1934 “base mineral index” for Swedish forest soils, and the basic nutrient budget estimates for whole-tree harvesting systems of the 1970s. Recent research...

  3. A Device for Simulating Soil Nutrient Extraction and Plant Uptake

    Institute of Scientific and Technical Information of China (English)

    YANG Xu-Jian; LAI Yong-Lin; MO Jin-Yu; SHEN Hong

    2012-01-01

    In situ evaluating the availability of soil nutrients has been a challenge.In this study,a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake (DSSNEPU) and its operating procedures were introduced.The device consists of a sampling tube,a fluid supply system,a low pressure system,a tube sheath and an elution cylinder.The sampling tube was firstly soaked in the solution of 0.5 mol L-1 NaHCO3 and then buried into soils.The fluid supply system was connected to the sampling tube and the deionized water was supplied.During the period,low pressure system started a vacuum for 3 min every 10 min interval.After extraction,the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 mol L-1 HC1.The elution solution was used for nutrient measurement.The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h.No significant increases of P and K were observed for longer extraction duration.The optimal temperature for extracting P and K was 30 ℃ in this experiment.Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system.Correlation analysis indicated that P and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake.The above results suggest that this device is applicable to assess the availability of nutrients in soils.

  4. Mathematical modelling of plant water and nutrient uptake

    Science.gov (United States)

    Roose, Tiina

    2010-05-01

    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

  5. Plant traits mediate consumer and nutrient control on plant community productivity and diversity.

    Science.gov (United States)

    Eskelinen, Anu; Harrison, Susan; Tuomi, Maria

    2012-12-01

    The interactive effects of consumers and nutrients on terrestrial plant communities, and the role of plant functional traits in mediating these responses, are poorly known. We carried out a six-year full-factorial field experiment using mammalian herbivore exclusion and fertilization in two habitat types (fertile and infertile alpine tundra heaths) that differed in plant functional traits related to resource acquisition and palatability. Infertile habitats were dominated by species with traits indicative of a slow-growing strategy: high C:N ratio, low specific leaf area, and high condensed tannins. We found that herbivory counteracted the effect of fertilization on biomass, and that this response differed between the two habitats and was correlated with plant functional traits. Live biomass dominated the treatment responses in infertile habitats, whereas litter accumulation dominated the treatment responses in fertile habitats and was strongly negatively associated with resident community tannin concentration. Species richness declined under herbivore exclusion and fertilization in fertile habitats, where litter accumulation was greatest. Community means of plant C:N ratio predicted treatment effects on diversity: fertilization decreased and herbivory increased dominance in communities originally dominated by plants with high C:N, while fertilization increased and herbivory diminished dominance in communities where low C:N species were abundant. Our results highlight the close interdependence between consumer effects, soil nutrients, and plant functional traits and suggest that plant traits may provide an improved understanding of how consumers and nutrients influence plant community productivity and diversity.

  6. Is nitrogen transfer among plants enhanced by contrasting nutrient-acquisition strategies?

    Science.gov (United States)

    Teste, François P; Veneklaas, Erik J; Dixon, Kingsley W; Lambers, Hans

    2015-01-01

    Nitrogen (N) transfer among plants has been found where at least one plant can fix N2 . In nutrient-poor soils, where plants with contrasting nutrient-acquisition strategies (without N2 fixation) co-occur, it is unclear if N transfer exists and what promotes it. A novel multi-species microcosm pot experiment was conducted to quantify N transfer between arbuscular mycorrhizal (AM), ectomycorrhizal (EM), dual AM/EM, and non-mycorrhizal cluster-rooted plants in nutrient-poor soils with mycorrhizal mesh barriers. We foliar-fed plants with a K(15) NO3 solution to quantify one-way N transfer from 'donor' to 'receiver' plants. We also quantified mycorrhizal colonization and root intermingling. Transfer of N between plants with contrasting nutrient-acquisition strategies occurred at both low and high soil nutrient levels with or without root intermingling. The magnitude of N transfer was relatively high (representing 4% of donor plant N) given the lack of N2 fixation. Receiver plants forming ectomycorrhizas or cluster roots were more enriched compared with AM-only plants. We demonstrate N transfer between plants of contrasting nutrient-acquisition strategies, and a preferential enrichment of cluster-rooted and EM plants compared with AM plants. Nutrient exchanges among plants are potentially important in promoting plant coexistence in nutrient-poor soils.

  7. [The content of nutrient elements of plant in KCl fertilizer].

    Science.gov (United States)

    Xu, Fang; Rui, Yu-Kui; Lin, Qiang; Zhang, Fu-Suo

    2009-03-01

    Potassium is one of the three most important plant nutrient elements, so many researchers pay attention on its fertilizer efficiency. But fertilizers were all industrial products containing many other nutrient elements in most experiments of fertilizer efficiency. All the other nutrient elements, including necessitous elements and beneficial elements in potassium fertilizer (KCl) were analyzed by method of ICP-MS. The results showed that KCl fertilizer contained many necessitous elements (Mg, Ca, Mn, Fe, Ni, Cu, Zn and Mo), the concentrations of them are 50.51, 1 309.48, 5.44, 500.83 microg x g(-1) and 65.54, 238.85, 212.44, 10.40 ng x g(-1) respectively; beneficial elements (Na, Al, Si, Co and Se) are 25 095.89, 3.83, 3.40 microg x g(-1) and 13.12, 23.25 ng x g(-1) respectively. All the above elements could influence the results of potassium fertilizer efficiency experiments, so pure fertilizer should be used in the future potassium fertilizer efficiency experiments.

  8. ALTERED SYMPATHETIC CONTROL OF NUTRIENT MOBILIZATION DURING PHYSICAL EXERCISE AFTER LESIONS IN THE VMH

    NARCIS (Netherlands)

    Balkan, B.; Strubbe, J.H.; Bruggink, J.E.; Steffens, A.B.

    1991-01-01

    To study the impact of obesity on sympathetic nervous regulation of nutrient mobilization, obese rats and lean controls were subjected to physical exercise. Male Wistar rats, rendered obese by bilateral electrolytic lesions of the ventromedial hypothalamus (VMH) were subjected to 15 min swimming. Pe

  9. ALTERED SYMPATHETIC CONTROL OF NUTRIENT MOBILIZATION DURING PHYSICAL EXERCISE AFTER LESIONS IN THE VMH

    NARCIS (Netherlands)

    Balkan, B.; Strubbe, J.H.; Bruggink, J.E.; Steffens, A.B.

    1991-01-01

    To study the impact of obesity on sympathetic nervous regulation of nutrient mobilization, obese rats and lean controls were subjected to physical exercise. Male Wistar rats, rendered obese by bilateral electrolytic lesions of the ventromedial hypothalamus (VMH) were subjected to 15 min swimming. Pe

  10. Soil nutrient competition in earth system models: an important but underappreciated driver of plant responses to nutrient fertilization

    Science.gov (United States)

    Zhu, Q.; Riley, W. J.; Tang, J.; Koven, C.

    2015-12-01

    Earth System Models (ESMs) used to project future biosphere-climate feedbacks rely on predictions of terrestrial carbon dynamics. Furthermore, soil nutrient availability strongly modulates land surface carbon dynamics, including plant sequestration of atmospheric CO2. Plant growth under future environmental changes (e.g., nitrogen and phosphorus deposition) depends on how well plants compete with microbial and abiotic competitors. Here, we surveyed recent developments of nutrient competition representations in ESMs that participated in the CMIP5 project. We found that nutrient competition is over-simplified despite its ecological significance. Existing ESMs either assume that soil-decomposing microbes (1) outcompete plants or (2) are evenly competitive, both of which are inconsistent with theoretical understanding and field observations. We compiled and synthesized global data of forest carbon productivity in response to nitrogen and phosphorus fertilization experiments. Using this synthesis, we show that existing ESMs with the first and second competition schemes lead to underestimation and overestimation, respectively, of fertilization effects on plant growth. We reduced these systematic biases by applying a new competition scheme in CLM4.5 and the essentially equivalent ACME land model (ALMv0) based on the Equilibrium Chemistry Approximation, which is based on classical equilibrium chemical kinetics theory. This approach dynamically updates nutrient competitiveness among multiple consumers (e.g., plants, decomposing microbes, nitrifier, denitrifier, mineral surfaces) as a function of soil nutrient status. There has been a long-term debate regarding how to implement theoretically realistic and computationally efficient nutrient competition schemes in ESMs. Our approach reconciles the complex nature of ecosystem nutrient competition with a computationally tractable approach applicable to ESMs. More importantly, our results imply that previous estimates of plant

  11. Nutrient allocation among plant organs across 13 tree species in three Bornean rain forests with contrasting nutrient availabilities.

    Science.gov (United States)

    Aoyagi, Ryota; Kitayama, Kanehiro

    2016-07-01

    Allocation of nitrogen (N) and phosphorus (P) among plant organs is an important factor regulating growth rate, which is a key ecological process associated with plant life-history strategies. However, few studies have explored how N and P investment in photosynthetic (leaves) and non-photosynthetic (stems and roots) organs changes in relation to depletion of each element. We investigated nutrient concentrations of plant organs in relation to whole-plant nutrient concentration (total nutrient weight per total biomass) as an index of nutrient status of each individual using the saplings of the 13 species in three tropical rain forests with contrasting N and P availabilities (tropical evergreen forests and tropical heath forests). We found a steeper decrease in foliar N concentration than foliar P concentration with decreasing whole-plant nutrient concentration. Moreover, the steeper decrease in foliar N concentration was associated with relatively stable N concentration in stems, and vice versa for P. We suggest that the depletion of N is associated with a rapid dilution of foliar N because the cell walls in non-photosynthetic organs function as an N sink. On the other hand, these species can maintain foliar P concentration by decreasing stem P concentrations despites the depletion of P. Our results emphasize the significance of non-photosynthetic organs as an N sink for understanding the variation of foliar nutrient concentrations for the tree species in the three Bornean rain forests with different N and P availabilities.

  12. From plant surface to plant metabolism: the uncertain fate of foliar-applied nutrients.

    Science.gov (United States)

    Fernández, Victoria; Brown, Patrick H

    2013-01-01

    The application of agrochemical sprays to the aerial parts of crop plants is an important agricultural practice world-wide. While variable effectiveness is often seen in response to foliar treatments, there is abundant evidence showing the beneficial effect of foliar fertilizers in terms of improving the metabolism, quality, and yields of crops. This mini-review is focused on the major bottlenecks associated with the uptake and translocation of foliar-applied nutrient solutions. A better understanding of the complex scenario surrounding the ultimate delivery of foliar-applied nutrients to sink cells and organs is essential for improving the effectiveness and performance of foliar fertilizers.

  13. Nutrient cycle of planted forest of Pinus tabulaeformis in the Miyun Reservoir Watershed, Beijing

    Institute of Scientific and Technical Information of China (English)

    Shihai LIU; Xinxiao YU

    2009-01-01

    We studied the nutrient cycle of a planted for-est ofPinus tabulaeformis in the Miyun Reservoir Water-shed, Beijing. Results show that the total biomass of P.tabulaeformis stands at age 29 in the experimental area is 92627 kg/hm2, and the total nutrient store is 695.17 kg/hm2 including nitrogen (N), phosphorus (P), kalium (K), calium (Ca) and magnesium (Mg). The sequence of their contents in different organs was given as follows: needle > branch >trunk > root. The annual amount of 85.37 kg/hm2 of five nutrient elements were assimilated by P. tabulaeformis,about 0.34% of the total store in soil, and 3.30% of available nutrient store in soil depth from 0 to 30 cm. The nutrient annual retention is 35.92 kg/hm2, annual returning 49.46kg/hm2, the rain input 26.04kg/hm2 to the five nutrient elements. The parameter absorption coefficient,utilization coefficient, cycle coefficient and turnover period were cited to describe the nutrient elements cycle characteristic of the planted forest ecosystem of P.tabulaeformis. The absorption coefficient is the ratio of plant nutrient element content to soil nutrient element content, and its sequence of five nutrient elements was given as follows: N > P > K > Ca > Mg. Utilization coef-ficient is the ratio of the nutrient element annual uptake amount to the nutrient element storage in standing crops,and its sequence of five nutrient elements was: Mg > K >P > N > Ca. The big utilization coefficient means more nutrients stored in the plant. The cycle coefficient is the ratio of the nutrient element annual return amount to the nutrient element annual uptake amount, its sequence:Ca > N > P > K > Mg. Turnover period is the ratio of the nutrient storage in the crops to the annual returning, its sequence: Mg > K > P > N > Ca.

  14. Plant Foliar Response to Soil Nutrient Availability Across Contrasting Geologic Settings

    Science.gov (United States)

    Castle, S. C.; Neff, J. C.

    2007-12-01

    Rock derived mineral nutrients such as P, Ca, Mg, Mn, and K play a significant, but poorly understood role in the structure and function of temperate forest ecosystems. Though these nutrients are not necessarily limiting to plant growth, they are essential to plant physiological functioning. In this study, we test the hypothesis that foliar nutrients are a proxy for soil nutrient availability across sites of different underlying geologies. Specifically, we focus on the plant nutrient-use strategies of rock derived nutrients (P and K) and how they relate to soil nutrient status. In order to assess the responses of plant species to nutrient availability, we monitored above ground net primary productivity (current annual increment + litterfall), plant chemistry, and soil nutrients for a period of 24 months. This research was completed in the San Juan Mountain region of southern Colorado, where there is a high local diversity of bedrock geochemistry. Within this region, two small sub-alpine basins were chosen; a sedimentary basin composed of Mesozoic cyclic limestone, sandstone & shale and a volcanic basin composed of Tertiary rhyolite. Across these basins, geology played a significant role in explaining the variability of rock derived nutrient availability. Initial results suggest that differences in bedrock geochemistry have little influence on the aboveground net primary production (ANPP) of plants or on the chemistry of foliar materials. This inflexibility of foliar chemistry to variations in nutrient availability suggests that genetic and physiologic controls play a strong role in determining the chemical content of plant materials. An alternative hypothesis is that deposition of eolian mineral dust into subalpine systems could play a role in offsetting the reliance of vegetation on deeper bedrock derived nutrient sources. An investigation is currently underway to assess the contribution of eolian dust derived nutrients to plant nutrition using Sr as a geochemical

  15. Plants adapted to nutrient limitation allocate less biomass into stems in an arid-hot grassland.

    Science.gov (United States)

    Yan, Bangguo; Ji, Zhonghua; Fan, Bo; Wang, Xuemei; He, Guangxiong; Shi, Liangtao; Liu, Gangcai

    2016-09-01

    Biomass allocation can exert a great influence on plant resource acquisition and nutrient use. However, the role of biomass allocation strategies in shaping plant community composition under nutrient limitations remains poorly addressed. We hypothesized that species-specific allocation strategies can affect plant adaptation to nutrient limitations, resulting in species turnover and changes in community-level biomass allocations across nutrient gradients. In this study, we measured species abundance and the concentrations of nitrogen and phosphorus in leaves and soil nutrients in an arid-hot grassland. We quantified species-specific allocation parameters for stems vs leaves based on allometric scaling relationships. Species-specific stem vs leaf allocation parameters were weighted with species abundances to calculate the community-weighted means driven by species turnover. We found that the community-weighted means of biomass allocation parameters were significantly related to the soil nutrient gradient as well as to leaf stoichiometry, indicating that species-specific allocation strategies can affect plant adaptation to nutrient limitations in the studied grassland. Species that allocate less to stems than leaves tend to dominate nutrient-limited environments. The results support the hypothesis that species-specific allocations affect plant adaptation to nutrient limitations. The allocation trade-off between stems and leaves has the potential to greatly affect plant distribution across nutrient gradients.

  16. Nutrient uptake and use efficiency in co-occurring plants along a disturbance and nutrient availability gradient in the boreal forests of the southwest Yukon, Canada

    NARCIS (Netherlands)

    Nitschke, Craig R.; Waeber, Patrick O.; Klaassen, Jan Willem; Dordel, Julia; Innes, John L.; Aponte, Cristina

    2017-01-01

    Aim: In boreal forest ecosystems plant productivity is typically constrained by mineral nutrient availability. In some boreal regions changes in nutrient availability have led to limited changes in productivity but large changes in plant composition. To determine the impact that a change in nutrient

  17. Nutrient presses and pulses differentially impact plants, herbivores, detritivores and their natural enemies.

    Science.gov (United States)

    Murphy, Shannon M; Wimp, Gina M; Lewis, Danny; Denno, Robert F

    2012-01-01

    Anthropogenic nutrient inputs into native ecosystems cause fluctuations in resources that normally limit plant growth, which has important consequences for associated food webs. Such inputs from agricultural and urban habitats into nearby natural systems are increasing globally and can be highly variable, spanning the range from sporadic to continuous. Despite the global increase in anthropogenically-derived nutrient inputs into native ecosystems, the consequences of variation in subsidy duration on native plants and their associated food webs are poorly known. Specifically, while some studies have examined the effects of nutrient subsidies on native ecosystems for a single year (a nutrient pulse), repeated introductions of nutrients across multiple years (a nutrient press) better reflect the persistent nature of anthropogenic nutrient enrichment. We therefore contrasted the effects of a one-year nutrient pulse with a four-year nutrient press on arthropod consumers in two salt marshes. Salt marshes represent an ideal system to address the differential impacts of nutrient pulses and presses on ecosystem and community dynamics because human development and other anthropogenic activities lead to recurrent introductions of nutrients into these natural systems. We found that plant biomass and %N as well as arthropod density fell after the nutrient pulse ended but remained elevated throughout the nutrient press. Notably, higher trophic levels responded more strongly than lower trophic levels to fertilization, and the predator/prey ratio increased each year of the nutrient press, demonstrating that food web responses to anthropogenic nutrient enrichment can take years to fully manifest themselves. Vegetation at the two marshes also exhibited an apparent tradeoff between increasing %N and biomass in response to fertilization. Our research emphasizes the need for long-term, spatially diverse studies of nutrient enrichment in order to understand how variation in the duration

  18. Nutrient Mass Balance for the Mobile River Basin in Alabama, Georgia, and Mississippi

    Science.gov (United States)

    Harned, D. A.; Harvill, J. S.; McMahon, G.

    2001-12-01

    The source and fate of nutrients in the Mobile River drainage basin are important water-quality concerns in Alabama, Georgia, and Mississippi. Land cover in the basin is 74 percent forested, 16 percent agricultural, 2.5 percent developed, and 4 percent wetland. A nutrient mass balance calculated for 18 watersheds in the Mobile River Basin indicates that agricultural non-point nitrogen and phosphorus sources and urban non-point nitrogen sources are the most important factors associated with nutrients in the streams. Nitrogen and phosphorus inputs from atmospheric deposition, crop fertilizer, biological nitrogen fixation, animal waste, and point sources were estimated for each of the 18 drainage basins. Total basin nitrogen inputs ranged from 27 to 93 percent from atmospheric deposition (56 percent mean), 4 to 45 percent from crop fertilizer (25 percent mean), rank test. The correlation analysis indicated that higher nitrogen concentrations in the streams are associated with urban areas and higher loads are associated with agriculture; high phosphorus output loads and concentrations are associated with agriculture. Higher nutrient loads in agricultural basins are partly an effect of basin size-- larger basins generate larger nutrient loads. Nutrient loads and concentrations showed no significant correlation to point-source inputs. Nitrogen loads were significantly (p0.5) higher in basins with greater cropland areas. Nitrogen concentrations also increased as residential, commercial, and total urban areas increased. Phosphorus loads were positively correlated with animal-waste inputs, pasture, and total agricultural land. Phosphorus concentrations were highest in basins with the greatest amounts of row-crop agriculture.

  19. The filter feeder Dreissena polymorpha affects nutrient, silicon, and metal(loid) mobilization from freshwater sediments.

    Science.gov (United States)

    Schaller, Jörg; Planer-Friedrich, Britta

    2017-05-01

    Organic sediments in aquatic ecosystems are well known sinks for nutrients, silicon, and metal(loid)s. Organic matter-consuming organisms like invertebrate shredders, grazers, and bioturbators significantly affect element fixation or remobilization by changing redox conditions or binding properties of organic sediments. Little is known about the effect of filter feeders, like the zebra mussel Dreissena polymorpha, an invasive organism in North American and European freshwater ecosystems. A laboratory batch experiment exposing D. polymorpha (∼1200 organisms per m(2)) to organic sediment from a site contaminated with arsenic, copper, lead, and uranium revealed a significant uptake and accumulation of arsenic, copper, iron, and especially uranium both into the soft body tissues and the seashell. This is in line with previous observations of metal(loid) accumulation from biomonitoring studies. Regarding its environmental impact, D. polymorpha significantly contributed to mobilization of silicon, iron, phosphorus, arsenic, and copper and to immobilization of uranium (p < 0.001), probably driven by redox conditions, microbial activity within the gut system, or active control of element homeostasis. No net mobilization or immobilization was observed for zinc and lead, because of their low mobility at the prevailing pH of 7.5-8.5. The present results suggest that D. polymorpha can both ameliorate (nutrient mobilization, immobilization of toxicants mobile under oxic conditions) or aggravate negative effects (mobilization of toxicants mobile under reducing conditions) in ecosystems. Relating the results of the present study to observed population densities in natural freshwater ecosystems suggests a significant influence of D. polymorpha on element cycling and needs to be considered in future studies.

  20. Accumulation of arsenic and nutrients by castor bean plants grown on an As-enriched nutrient solution.

    Science.gov (United States)

    Melo, E E C; Costa, E T S; Guilherme, L R G; Faquin, V; Nascimento, C W A

    2009-08-30

    Phytoextraction is a remediation technique that consists in using plants to remove contaminants from soils and water. This study evaluated arsenic (As) accumulation in Castor bean (Ricinus communis cv. Guarany) grown in nutrient solution in order to assess its phytoextraction ability. Castor bean plants were grown under greenhouse conditions in pots containing a nutrient solution amended with increasing doses of As (0, 10, 50, 100, 250, 500 and 5000 microg L(-1)) in a completely randomized design with four replications. Shoot and roots dry matter production as well as arsenic and nutrient tissue concentrations were measured at the end of the experiment. The results showed that increasing As concentration in nutrient solution caused a decrease in shoot and root biomass but did not result in severe toxicity symptoms in castor bean growing under a range of As concentration from 0 to 5000 microg L(-1). The As doses tested did not affect the accumulation of nutrients by castor bean. Although castor bean did not pose characteristics of a plant suitable for commercial phytoextraction, it could be useful for revegetation of As-contaminated areas while providing an additional income by oil production.

  1. Uptake and partitioning of nutrients in blackberry and raspberry and evaluating plant nutrient status for accurate assessment of fertilizer requirements

    Science.gov (United States)

    Raspberry and blackberry plantings have a relatively low nutrient requirement compared to many other perennial fruit crops. Annual total N accumulation ranged from 62-110 lb/a in red raspberry and 33-39 lb/a in blackberry. Primocanes rely primarily on fertilizer N for growth, whereas floricane growt...

  2. Hydroponics: A Versatile System to Study Nutrient Allocation and Plant Responses to Nutrient Availability and Exposure to Toxic Elements.

    Science.gov (United States)

    Nguyen, Nga T; McInturf, Samuel A; Mendoza-Cózatl, David G

    2016-07-13

    Hydroponic systems have been utilized as one of the standard methods for plant biology research and are also used in commercial production for several crops, including lettuce and tomato. Within the plant research community, numerous hydroponic systems have been designed to study plant responses to biotic and abiotic stresses. Here we present a hydroponic protocol that can be easily implemented in laboratories interested in pursuing studies on plant mineral nutrition. This protocol describes the hydroponic system set up in detail and the preparation of plant material for successful experiments. Most of the materials described in this protocol can be found outside scientific supply companies, making the set up for hydroponic experiments less expensive and convenient. The use of a hydroponic growth system is most advantageous in situations where the nutrient media need to be well controlled and when intact roots need to be harvested for downstream applications. We also demonstrate how nutrient concentrations can be modified to induce plant responses to both essential nutrients and toxic non-essential elements.

  3. Root growth and plant biomass in Lolium perenne exploring a nutrient-rich patch in soil.

    Science.gov (United States)

    Nakamura, Ryoji; Kachi, Naoki; Suzuki, Jun-Ichirou

    2008-11-01

    We investigated soil exploration by roots and plant growth in a heterogeneous environment to determine whether roots can selectively explore a nutrient-rich patch, and how nutrient heterogeneity affects biomass allocation and total biomass before a patch is reached. Lolium perenne L. plants were grown in a factorial experiment with combinations of fertilization (heterogeneous and homogeneous) and day of harvest (14, 28, 42, or 56 days after transplanting). The plant in the heterogeneous treatment was smaller in its mean total biomass, and allocated more biomass to roots. The distributions of root length and root biomass in the heterogeneous treatment did not favor the nutrient-rich patch, and did not correspond to the patchy distribution of inorganic nitrogen. Specific root length (length/biomass) was higher and root elongation was more extensive both laterally and vertically in the heterogeneous treatment. These characteristics may enable plants to acquire nutrients efficiently and increase the probability of encountering nutrient-rich patches in a heterogeneous soil. However, heterogeneity of soil nutrients would hold back plant growth before a patch was reached. Therefore, although no significant selective root placement in the nutrient-rich patch was observed, plant growth before reaching nutrient-rich patches differed between heterogeneous and homogeneous environments.

  4. Some aspects of interactions between heavy metals and plant mineral nutrients

    OpenAIRE

    Anna Siedlecka

    2014-01-01

    Heavy metals are aggresive environmental pollutants. They are easily taken up by plants and they are strong stess factors for plant metabolism. Heavy metals influence includes also disturbances in plant mineral nutrition by competition with other nutrients. Typical symptoms of heavy metals toxicity are often similar or even the same like symptoms of some essential nutrients deficiency. The aim of this paper is to discuss mechanisms of some heavy metals uptake and possible ways of their influe...

  5. Plant Biomass Leaching for Nutrient Recovery in Closed Loop Systems Project

    Science.gov (United States)

    Zeitlin, Nancy P.; Wheeler, Raymond (Compiler); Lunn, Griffin

    2015-01-01

    Plants will be important for food and O2 production during long term human habitation in space. Recycling of nutrients (e.g., from waste materials) could reduce the resupply costs of fertilizers for growing these plants. Work at NASA's Kennedy Space Center has shown that ion exchange resins can extract fertilizer (plant essential nutrients) from human waste water, after which the residual brine could be treated with electrodialysis to recover more water and produce high value chemicals (e.g., acids and bases). In habitats with significant plant production, inedible biomass becomes a major source of solid waste. To "close the loop" we also need to recover useful nutrients and fertilizer from inedible biomass. We are investigating different approaches to retrieve nutrients from inedible plant biomass, including physical leaching with water, processing the biomass in bioreactors, changing the pH of leaching processing, and/or conducting multiple leaches of biomass residues.

  6. Effect of Cultural Measures on Nutrient Contents in Rice Plants with Erect Panicles

    Institute of Scientific and Technical Information of China (English)

    WANGBOLUN; ZOUBANGJItffu

    1999-01-01

    Field experiments were carried out with rice variety of Shenong 91 of short culms and erect panicles to study nutrient contents in high-yiedlding rice plants and to increase rice yield by appropriate fertilization.Nitrogen,phosphorus,potassium,magnesium,zinc,manganese,iron and copper contents in rice plants varied with different treatment factors.The relationship between the nutrient contents and treatment factors could be simulated using a multiple quadratic equation.The nutrient contents in plants should be appropriate for high-yielding rice.If the mean nutrient content in rice plants producuing 11 t ha-1 or more of grain (uj) was set as the standard value and the standard deviation (σj) was set as the range of variation,the nutrient content in high-yielding rice plants should be μj±1.99σj.Rice leaves were sensitive to the nutrient elements.Heavy nitrogen dressing increased the content of nitrogen in rice plants.Sparse transplanting also increased nitrogen content,Improper application of nitrogen,phosphorus and potassium could affect the nutrient contents and decrease the grain yield.

  7. Current understanding on ethylene signaling in plants: the influence of nutrient availability.

    Science.gov (United States)

    Iqbal, Noushina; Trivellini, Alice; Masood, Asim; Ferrante, Antonio; Khan, Nafees A

    2013-12-01

    The plant hormone ethylene is involved in many physiological processes, including plant growth, development and senescence. Ethylene also plays a pivotal role in plant response or adaptation under biotic and abiotic stress conditions. In plants, ethylene production often enhances the tolerance to sub-optimal environmental conditions. This role is particularly important from both ecological and agricultural point of views. Among the abiotic stresses, the role of ethylene in plants under nutrient stress conditions has not been completely investigated. In literature few reports are available on the interaction among ethylene and macro- or micro-nutrients. However, the published works clearly demonstrated that several mineral nutrients largely affect ethylene biosynthesis and perception with a strong influence on plant physiology. The aim of this review is to revisit the old findings and recent advances of knowledge regarding the sub-optimal nutrient conditions on the effect of ethylene biosynthesis and perception in plants. The effect of deficiency or excess of the single macronutrient or micronutrient on the ethylene pathway and plant responses are reviewed and discussed. The synergistic and antagonist effect of the different mineral nutrients on ethylene plant responses is critically analyzed. Moreover, this review highlights the status of information between nutritional stresses and plant response, emphasizing the topics that should be further investigated. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Comparison of nutrient acquisition in exotic plant species and congeneric natives

    NARCIS (Netherlands)

    Meisner, A.; De Boer, W.; Verhoeven, K.J.F.; Boschker, H.T.S.; Van der Putten, W.H.

    2011-01-01

    1.The ability of exotic plant species to establish and expand in new areas may be enhanced by a relatively high ability to acquire soil nutrients. To test this hypothesis, we predicted that the capacity for nutrient acquisition would be higher in seedlings of exotic species than in seedlings of nati

  9. Effects of nutrients and fish on periphyton and plant biomass across a European latitudinal gradient

    NARCIS (Netherlands)

    Bécares, E.; Gomá, J.; Fernández-Aláez, M.; Fernández-Aláez, C.; Romo, S.; Rosa Miracle, M.; Ståhl-Delbanco, A.; Hansson, L-A.; Gyllström, M.; van de Bund, W.; Van Donk, E.; Kairesalo, T.; Hietala, J.; Stephen, D.; Balayla, D.; Moss, B.

    2008-01-01

    Replicated, factorial mesocosm experiments were conducted across Europe to study the effects of nutrient enrichment and fish density on macrophytes and on periphyton chlorophyll a (chl-a) with regard to latitude. Periphyton chl-a densities and plant decline were significantly related to nutrient loa

  10. Effects of nutrients and fish on periphyton and plant biomass across a European latitudinal gradient

    NARCIS (Netherlands)

    Bécares, E.; Gomá, J.; Fernández-Aláez, M.; Fernández-Aláez, C.; Romo, S.; Rosa Miracle, M.; Ståhl-Delbanco, A.; Hansson, L-A.; Gyllström, M.; van de Bund, W.; Van Donk, E.; Kairesalo, T.; Hietala, J.; Stephen, D.; Balayla, D.; Moss, B.

    2008-01-01

    Replicated, factorial mesocosm experiments were conducted across Europe to study the effects of nutrient enrichment and fish density on macrophytes and on periphyton chlorophyll a (chl-a) with regard to latitude. Periphyton chl-a densities and plant decline were significantly related to nutrient

  11. Nutrient and metal uptake in wetland plants at stormwater detension ponds

    DEFF Research Database (Denmark)

    Istenic, Darja; Arias, Carlos Alberto; Brix, Hans

    2011-01-01

    Nutrients and metals were analysed in tissues of various wetland plants growing in stormwater detention ponds in Denmark. Nutrient and metal concentrations in below and aboveground tissues were compared to the concentrations of the adjacent sediment. The results showed accumulation of heavy metal...

  12. The performance of plant species in removing nutrients from ...

    African Journals Online (AJOL)

    2011-10-26

    Oct 26, 2011 ... The discharge was collected from a drainage pipe at the base of each of the 150 containers. ... The species that performed well for all three nutrients include .... layers were placed below the Malmesbury shale, comprising of.

  13. Contribution of Wastewater Treatment Plant Effluents to Nutrient Dynamics in Aquatic Systems: A Review

    Science.gov (United States)

    Carey, Richard O.; Migliaccio, Kati W.

    2009-08-01

    Excessive nutrient loading (considering nitrogen and phosphorus) is a major ongoing threat to water quality and here we review the impact of nutrient discharges from wastewater treatment plants (WWTPs) to United States (U.S.) freshwater systems. While urban and agricultural land uses are significant nonpoint nutrient contributors, effluent from point sources such as WWTPs can overwhelm receiving waters, effectively dominating hydrological characteristics and regulating instream nutrient processes. Population growth, increased wastewater volumes, and sustainability of critical water resources have all been key factors influencing the extent of wastewater treatment. Reducing nutrient concentrations in wastewater is an important aspect of water quality management because excessive nutrient concentrations often prevent water bodies from meeting designated uses. WWTPs employ numerous physical, chemical, and biological methods to improve effluent water quality but nutrient removal requires advanced treatment and infrastructure that may be economically prohibitive. Therefore, effluent nutrient concentrations vary depending on the particular processes used to treat influent wastewater. Increasingly stringent regulations regarding nutrient concentrations in discharged effluent, along with greater freshwater demand in populous areas, have led to the development of extensive water recycling programs within many U.S. regions. Reuse programs provide an opportunity to reduce or eliminate direct nutrient discharges to receiving waters while allowing for the beneficial use of reclaimed water. However, nutrients in reclaimed water can still be a concern for reuse applications, such as agricultural and landscape irrigation.

  14. Nutrient abatement potential and abatement costs of waste water treatment plants in the Baltic Sea region.

    Science.gov (United States)

    Hautakangas, Sami; Ollikainen, Markku; Aarnos, Kari; Rantanen, Pirjo

    2014-04-01

    We assess the physical potential to reduce nutrient loads from waste water treatment plants in the Baltic Sea region and determine the costs of abating nutrients based on the estimated potential. We take a sample of waste water treatment plants of different size classes and generalize its properties to the whole population of waste water treatment plants. Based on a detailed investment and operational cost data on actual plants, we develop the total and marginal abatement cost functions for both nutrients. To our knowledge, our study is the first of its kind; there is no other study on this issue which would take advantage of detailed data on waste water treatment plants at this extent. We demonstrate that the reduction potential of nutrients is huge in waste water treatment plants. Increasing the abatement in waste water treatment plants can result in 70 % of the Baltic Sea Action Plan nitrogen reduction target and 80 % of the Baltic Sea Action Plan phosphorus reduction target. Another good finding is that the costs of reducing both nutrients are much lower than previously thought. The large reduction of nitrogen would cost 670 million euros and of phosphorus 150 million euros. We show that especially for phosphorus the abatement costs in agriculture would be much higher than in waste water treatment plants.

  15. Plant species differ in early seedling growth and tissue nutrient responses to arbuscular and ectomycorrhizal fungi.

    Science.gov (United States)

    Holste, Ellen K; Kobe, Richard K; Gehring, Catherine A

    2017-04-01

    Experiments with plant species that can host both arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) are important to separating the roles of fungal type and plant species and understanding the influence of the types of symbioses on plant growth and nutrient acquisition. We examined the effects of mycorrhizal fungal type on the growth and tissue nutrient content of two tree species (Eucalyptus grandis and Quercus costaricensis) grown under four nutrient treatments (combinations of low versus high nitrogen (N) and phosphorus (P) with different N:P ratios) in the greenhouse. Trees were inoculated with unidentified field mixtures of AMF or EMF species cultivated on root fragments of AMF- or EMF-specific bait plants. In E. grandis, inoculation with both AMF and EMF positively affected belowground plant dry weight and negatively affected aboveground dry weight, while only inoculation with AMF increased tissue nutrient content. Conversely, Q. costaricensis dry weight and nutrient content did not differ significantly among inoculation treatments, potentially due to its dependence on cotyledon reserves for growth. Mineral nutrition of both tree species differed with the ratio of N to P applied while growth did not. Our results demonstrate that both tree species' characteristics and the soil nutrient environment can affect how AMF and EMF interact with their host plants. This research highlights the importance of mycorrhizal fungal-tree-soil interactions during early seedling growth and suggests that differences between AMF and EMF associations may be crucial to understanding forest ecosystem functioning.

  16. Ash characteristics and plant nutrients in some aquatic biomasses

    Science.gov (United States)

    Masto, Reginald; Pandit, Ankita; George, Joshy; Mukhopadhyay, Sangeeta; Selvi, Vetrivel; Ram, Lal

    2016-04-01

    is released at 800 °C. The salgging tendencies based on both base: acid ratio and slagging factor, fouling probabilities based on fouling factors is in the order Hydrilla > Eichornia > Lemna > Spirogyra. Among the different heavy metals Zn, Pb, Cu, and Ni have concentration > 100 mg/kg; Cr and V content was > 50 mg/kg; Co, > 10 mg/kg. In general the heavy metal contents were higher in Spirogyra. Due to the volatile nature Cd and Pb decreases in ash with temperature and is lost continuously in flue gas. Plant nutrient content was relatively higher for Eichornia: K (8 - 12.8 %), P (5.7 - 7.3 %), Ca (9.2 - 10.8 %), Mg (2.8 - 3.6 %), S (1.9 - 2.9 %), Zn (0.033 - 0.045 %), Fe (3.3 - 4.7 %), Cu (0.009 - 0.013 %), Mn (0.8 -1.3%). Among the four biomasses we have studied, Eichornia could be a potential candidate for energy extraction in view of its C content and widespread availability in many parts of the globe, and fast multiplication associated with the eutrophication of water bodies.

  17. Ecophysiology of novel core phylotypes in activated sludge wastewater treatment plants with nutrient removal

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Awata, Takanori; Nierychlo, Marta

    An in depth understanding of the ecology of activated sludge nutrient removal wastewater treatment systems requires detailed knowledge of the community composition and metabolic activities of individual members. Recent 16S rRNA gene amplicon surveys of activated sludge wastewater treatment plants...... with nutrient removal in Denmark indicate a core set of bacterial genera. These core genera are suggested to be responsible for the bulk of nutrient transformations underpinning the functions of these plants. While we know the basic in situ activities of some of these genera, there is little to no information...

  18. Characterization of the in situ ecophysiology of novel phylotypes in nutrient removal activated sludge treatment plants

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Awata, Takanori; Nierychlo, Marta

    2015-01-01

    An in depth understanding of the ecology of activated sludge nutrient removal wastewater treatment systems requires detailed knowledge of the community composition and metabolic activities of individual members. Recent 16S rRNA gene amplicon surveys of activated sludge wastewater treatment plants...... with nutrient removal indicate the presence of a core set of bacterial genera. These organisms are likely responsible for the bulk of nutrient transformations underpinning the functions of these plants. While the basic activities of some of these genera in situ are known, there is little to no information...

  19. Plant Growth Environments with Programmable Relative Humidity and Homogeneous Nutrient Availability

    Science.gov (United States)

    Lind, Kara R.; Lee, Nigel; Sizmur, Tom; Siemianowski, Oskar; Van Bruggen, Shawn; Ganapathysubramaniam, Baskar

    2016-01-01

    We describe the design, characterization, and use of “programmable”, sterile growth environments for individual (or small sets of) plants. The specific relative humidities and nutrient availability experienced by the plant is established (RH between 15% and 95%; nutrient concentration as desired) during the setup of the growth environment, which takes about 5 minutes and hydroponics conditions (e.g., root phenotyping, complete control over nutrient composition, scalability) and soil conditions (e.g., aeration of roots, shading of roots), while being comparable in cost and setup time to Magenta® boxes. PMID:27304431

  20. The plant nitrogen mobilization promoted by Colletotrichum lindemuthianum in Phaseolus leaves depends on fungus pathogenicity.

    Science.gov (United States)

    Tavernier, Virginie; Cadiou, Sandrine; Pageau, Karine; Laugé, Richard; Reisdorf-Cren, Michèle; Langin, Thierry; Masclaux-Daubresse, Céline

    2007-01-01

    Nitrogen plays an essential role in the nutrient relationship between plants and pathogens. Some studies report that the nitrogen-mobilizing plant metabolism that occurs during abiotic and biotic stress could be a 'slash-and-burn' defence strategy. In order to study nitrogen recycling and mobilization in host plants during pathogen attack and invasion, the Colletotrichum lindemuthianum/Phaseolus vulgaris interaction was used as a model. C. lindemuthianum is a hemibiotroph that causes anthracnose disease on P. vulgaris. Non-pathogenic mutants and the pathogenic wild-type strain were used to compare their effects on plant metabolism. The deleterious effects of infection were monitored by measuring changes in chlorophyll, protein, and amino acid concentrations. It was shown that amino acid composition changed depending on the plant-fungus interaction and that glutamine accumulated mainly in the leaves infected by the pathogenic strain. Glutamine accumulation correlated with the accumulation of cytosolic glutamine synthetase (GS1 alpha) mRNA. The most striking result was that the GS1 alpha gene was induced in all the fungus-infected leaves, independent of the strain used for inoculation, and that GS1 alpha expression paralleled the PAL3 and CHS defence gene expression. It is concluded that a role of GS1 alpha in plant defence has to be considered.

  1. Examining Dehydration and Hypoxic Stress in Wheat Plants Using a Porous Tube Plant Nutrient Delivery System Developed for Microgravity

    Science.gov (United States)

    Dreschel, T. W.; Hall, C. R.; Foster, T. E.; Salganic, M.; Warren, L.; Corbett, M.

    2005-01-01

    The Porous Tube Plant Nutrient Delivery System (PTPNDS) was designed for NASA to grow plants in microgravity of space. The system utilizes a controlled fluid loop to supply nutrients and water to plant roots growing on a ceramic surface moistened by capiflary action. A PTPNDS test bed was developed and utilizing remote sensing systems, spectral analyses procedures, gas-exchange, and fluorescence measurements, we examined differences in plant water status for wheat plants (Triticum aestivum, cv. Perigee) grown in a modified growth chamber during the summers of 2003 and 2004. Some differences in plant performance were detectable in the gas-exchange and fluorescence measurements. For instance, in both years the plants grown with the most available water had the lowest rates of photosynthesis and exhibited higher proportions of non-photochemical quenching particularly under low light levels. In addition, small differences in mean leaf water content between treatments were detected using spectral reflectance analyses.

  2. The introduction of mobile plant clinics to Uganda

    DEFF Research Database (Denmark)

    Danielsen, Solveig; Mutebi, Emmanuel

    Four mobile (or community-based) plant health clinics were started in Uganda on a pilot basis in 2005 as an attempt to ensure better plant health advisory services for small-scale farmers.  This new way of delivering primary plant healthcare to farmers has attracted wider interest and the Ministry......, Makerere University and CABI. The purpose of this study was to gather results and lessons learned from the pilot period to inform future plant clinic interventions. The study covers issues of organisation and management, clinic operation and performance as well as clinic use and preliminary evidence...

  3. Effect of salinity stress on plant fresh weight and nutrient ...

    African Journals Online (AJOL)

    user

    2011-03-07

    Mar 7, 2011 ... Although Brassica species produce maximum yield under normal soil and ..... germination of seeds and growth of young plants of hordeum vulgare, ... weight and plant growth of soybean (Glycine max L. Merrill) cultivars.

  4. Nutrient leaching when compost is part of plant growth media

    Science.gov (United States)

    Bioretention cells collect urban runoff and are used to slow storm water surge, reduce or remove nutrients or other pollutants, and provide aesthetics to the landscape. A cell is filled with soil mixed with sand, compost, and other materials, and underlain by an aggregate layer and drainage pipe. Th...

  5. Plant and soil nutrient stoichiometry along primary ecological successions: Is there any link?

    Science.gov (United States)

    Di Palo, Francesca; Fornara, Dario A

    2017-01-01

    Ecological stoichiometry suggests that plant Nitrogen (N)-to-Phosphorus (P) ratios respond to changes in both soil N:P stoichiometry and soil N and P availability. Thus we would expect that soil and plant N:P ratios be significantly related along natural gradients of soil development such as those associated with primary ecological successions. Here we explicitly search for linkages between plant and soil N:P stoichiometry along four primary successions distributed across Europe. We measured N and P content in soils and plant compartments (leaf, stem and root) of 72 wild plant species distributed along two sand dune and two glacier successions where soil age ranges from few to thousand years old. Overall we found that soil N:P ratios strongly increased along successional stages, however, plant N:P ratios were neither related to soil N:P stoichiometry nor to changes in soil N and P availability. Instead changes in plant nutrient stoichiometry were "driven" by plant-functional-group identity. Not only N:P ratios differed between legumes, grasses and forbs but each of these plant functional groups maintained N:P ratios relatively constant across pioneer, middle and advanced successional stages. Our evidence is that soil nutrient stoichiometry may not be a good predictor of changes in plant N:P stoichiometry along natural primary ecological successions, which have not reached yet a retrogressive stage. This could be because wild-plants rely on mechanisms of internal nutrient regulation, which make them less dependent to changes in soil nutrient availability under unpredictable environmental conditions. Further studies need to clarify what underlying evolutionary and eco-physiological mechanisms determine changes in nutrient stoichiometry in plant species distributed across natural environmental gradients.

  6. Competition for light and nutrients in layered communities of aquatic plants

    NARCIS (Netherlands)

    Van Gerven, Luuk P.A.; de Klein, J.J.M; Gerla, Daan J.; Kooi, B.W.; Kuiper, Jan J.; Mooij, Wolf M.

    2015-01-01

    Dominance of free-floating plants poses a threat to biodiversity in many freshwater ecosystems. Here we propose a theoretical framework to understand this dominance, by modeling the competition for light and nutrients in a layered community of floating and submerged plants. The model shows that at h

  7. Competition for light and nutrients in layered communities of aquatic plants

    NARCIS (Netherlands)

    Gerven, van Luuk P.A.; Klein, de Jeroen J.M.; Gerla, Daan J.; Kooi, Bob W.; Kuiper, Jan J.; Mooij, Wolf M.

    2015-01-01

    Dominance of free-floating plants poses a threat to biodiversity in many freshwater ecosystems. Here we propose a theoretical framework to understand this dominance, by modeling the competition for light and nutrients in a layered community of floating and submerged plants. The model shows that a

  8. Competition for Light and Nutrients in Layered Communities of Aquatic Plants

    NARCIS (Netherlands)

    van Gerven, L.P.A.; de Klein, J.J.M.; Gerla, D.J.; Kooi, B.W.; Kuiper, J.J.; Mooij, W.M.

    2015-01-01

    Dominance of free-floating plants poses a threat to biodiversity in many freshwater ecosystems. Here we propose a theoretical framework to understand this dominance, by modeling the competition for light and nutrients in a layered community of floating and submerged plants. The model shows that at h

  9. Reciprocal effects of litter from exotic and congeneric native plant species via soil nutrients

    NARCIS (Netherlands)

    Meisner, A.; Boer, de W.; Cornelissen, J.H.C.; Putten, van der W.H.

    2012-01-01

    Invasive exotic plant species are often expected to benefit exclusively from legacy effects of their litter inputs on soil processes and nutrient availability. However, there are relatively few experimental tests determining how litter of exotic plants affects their own growth conditions compared to

  10. Impact of FGD gypsum on soil fertility and plant nutrient uptake

    Science.gov (United States)

    Use of FGD gypsum is thought to improve soil productivity and increase plant production. Thus, a study was conducted to evaluate the effects of FGD gypsum on yield, plant nutrient uptake and soil productivity. The study was conducted on an established bermudagrass pasture. Poultry litter was applied...

  11. Dynamics of water and nutrients for potted plants induced by flooded bench fertigation: experiments and simulation.

    NARCIS (Netherlands)

    Otten, W.

    1994-01-01

    Dynamics of water and nutrients as affected by physical and chemical characteristics of a substrate, fertigation method and schedule, and plant uptake were studied for a flooded bench fertigation system for potted plants, through a detailed experimental study of the root environment and a simulation

  12. Competition for light and nutrients in layered communities of aquatic plants.

    Science.gov (United States)

    van Gerven, Luuk P A; de Klein, Jeroen J M; Gerla, Daan J; Kooi, Bob W; Kuiper, Jan J; Mooij, Wolf M

    2015-07-01

    Dominance of free-floating plants poses a threat to biodiversity in many freshwater ecosystems. Here we propose a theoretical framework to understand this dominance, by modeling the competition for light and nutrients in a layered community of floating and submerged plants. The model shows that at high supply of light and nutrients, floating plants always dominate due to their primacy for light, even when submerged plants have lower minimal resource requirements. The model also shows that floating-plant dominance cannot be an alternative stable state in light-limited environments but only in nutrient-limited environments, depending on the plants' resource consumption traits. Compared to unlayered communities, the asymmetry in competition for light-coincident with symmetry in competition for nutrients-leads to fundamentally different results: competition outcomes can no longer be predicted from species traits such as minimal resource requirements ([Formula: see text] rule) and resource consumption. Also, the same two species can, depending on the environment, coexist or be alternative stable states. When applied to two common plant species in temperate regions, both the model and field data suggest that floating-plant dominance is unlikely to be an alternative stable state.

  13. Influence of calcium foliar fertilization on plant growth, nutrient concentrations, and fruit quality of papaya.

    Science.gov (United States)

    Calcium (Ca) is a major plant nutrient that affects cell wall and plasma membrane formation and plays a key role in plant growth and biomass production. It can be used to decrease fruit decay and increase firmness and shelf life. So far, little attention has been paid to investigate the effects of f...

  14. Comparison of four aquatic plant treatment systems for nutrient removal from eutrophied water.

    Science.gov (United States)

    Li, Jihua; Yang, Xiaoying; Wang, Zhengfang; Shan, Ying; Zheng, Zheng

    2015-03-01

    Nutrient removal behaviors of four aquatic plant treatment systems (Oenanthe javanica, Iris pseudacorus L., Canna lily, and Potamogeton crispus) were systematically examined and compared. The kinetics of nutrient uptake were conducted with the standard depletion method. All four aquatic species exhibited a strong preference of ammonium nitrogen (NH4(+)-N) over nitrate nitrogen (NO3(-)-N) and nitrite nitrogen (NO2(-)-N). Main pathways of nutrient removal in the aquatic plant treatment system were examined in details. It was estimated that direct assimilation by plants accounted for 28.2-34.5% of N reduction and 25.2-33.4% of P reduction while substrate absorption accounted for 7.2-25.5% of N reduction and 7.3-25.0% of P reduction. The activity of urease and phosphatase in the substrates could indicate the aquatic plant treatment system's capability for reducing TN and soluble P load.

  15. Nutrient Recovery of Plant Leachates Under Thermal, Biological, and Photocatalytic Pretreatments

    Science.gov (United States)

    Wong, Les

    2015-01-01

    Nutrient recovery has always been a problem for long distance and long-term space missions. To allow humans to man these missions, a steady source of oxygen, water, and food are necessary for survival beyond Earth's atmosphere. Plants are currently an area of interest since they are capable of providing all three resources for life sustainability. We are currently interested in nutrient recovery for future plant growth and simple aqueous leachate extractions can recover some of the nutrients. However, leaching plants also removes water-soluble organic plant wastes, which inhibits plant growth if not separated properly. To combat the issues with waste and maximize nutrient recovery, we are attempting to pre-treat the plant matter using biological, thermal, and photocatalytic methods before subjecting the solution with variable-strength acid digestion. For the biological method, the inoculums: mixed heterotrophic/nitrifying bioreactor effluent and Trichoderma vessei are used in an attempt to liberate more nutrients from the plant matter. For the thermal method, plants are subjected to varying temperatures at different retention times to determine nutrient recovery. Lastly, the photocatalytic method utilizes TiO (sub 2)'s oxidizing abilities under specific pHs and retention times to reduce organic wastes and improve nutrient gains. A final acid digestion serves to liberate nutrients even further in order to maximize recovery. So far, we have tested ideal acid digestion variables for practicality and performance in our experiments. We found that a low retention time of 10 minutes and a high acid concentration of 0.1 and 1 mole HCl were the most effective at nutrient recovery. For space travel purposes, 0.1 mole currently looks like a viable acid digestion to use since it is relatively effective and sustainable from a mass and energy balance if acid recovery can be performed on waste brines. Biological pretreatments do not look to be too effective and the thermal and

  16. Nutrient accumulation of Leucaena leucocephala with different planting spacings

    Energy Technology Data Exchange (ETDEWEB)

    Hu, T.W.; Cheng, W.E.; Shen, T.A.

    1983-01-01

    Data are given on the accumulation of N, P, K, Ca and Mg, and the removal of these nutrients at harvest, in 3-year-old trees established at spacings of 2x2, 2x1, 1x1, 1x0.5, and 0.5x0.5 m at Chia-Lin, Taiwan. Differences between spacings were not significant. 3 references.

  17. A review on beneficial effects of rhizosphere bacteria on soil nutrient availability and plant nutrient uptake.

    OpenAIRE

    Osorio Vega, Nelson Walter

    2011-01-01

    Este artículo se constituye en una revisión de los beneficios de bacterias rizosféricas sobre la nutrición vegetal. La interacción entre planta y bacterias solubilizadoras de fosfato es explicada en mayor detalle y usada como modelo para ilustrar el rol que algunas bacterias de la rizosfera juegan en la disponibilidad de nutrientes en el suelo. Las condiciones ambientales de la rizosfera también se discuten con detalle. Los beneficios de estas bacterias han sido obtenidos, y mejorados, en pre...

  18. When Michaelis and Menten met Holling: towards a mechanistic theory of plant nutrient foraging behaviour.

    Science.gov (United States)

    McNickle, Gordon G; Brown, Joel S

    2014-10-22

    Plants are adept at assessing and responding to nutrients in soil, and generally proliferate roots into nutrient-rich patches. An analogy between this growth response and animal foraging movement is often drawn, but because of differences between plants and animals it has not always been clear how to directly apply existing foraging theory to plants. Here we suggest one way to unite pre-existing ideas in plant nutrient uptake with foraging theory. First, we show that the Michaelis-Menten equation used by botanists and the Holling disc equation used by zoologists are actually just rearrangements of the same functional response. This mathematical unity permits the translation of existing knowledge about the nutrient uptake physiology of plants into the language of foraging behaviour, and as a result gives botanists direct access to foraging theory. Second, we developed a model of root foraging precision based on the Holling disc equation and the marginal value theorem, and parameterize it from the literature. The model predicts (i) generally plants should invest in higher quality patches compared to lower quality patches, and as patch background-contrast increases; (ii) low encounter rates between roots and nutrients result in high root foraging precision; and (iii) low handling times for nutrients should result in high root foraging precision. The available data qualitatively support these predictions. Third, to parameterize the model above we undertook a review of the literature. From that review we obtained parameter estimates for nitrate and/or ammonium uptake for 45 plant species from 38 studies. We observe that the parameters ranged over six orders of magnitude, there was no trade-off in foraging ability for nitrate versus ammonium: plants that were efficient foragers for one form of nitrogen were efficient foragers for the other, and there was also no phylogenetic signal in the parameter estimates. Published by Oxford University Press on behalf of the Annals

  19. Impact of organic carbon and nutrients mobilized during chemical oxidation on subsequent bioremediation of a diesel-contaminated soil.

    Science.gov (United States)

    Sutton, Nora B; Grotenhuis, Tim; Rijnaarts, Huub H M

    2014-02-01

    Remediation with in situ chemical oxidation (ISCO) impacts soil organic matter (SOM) and the microbial community, with deleterious effects on the latter being a major hurdle to coupling ISCO with in situ bioremediation (ISB). We investigate treatment of a diesel-contaminated soil with Fenton's reagent and modified Fenton's reagent coupled with a subsequent bioremediation phase of 187d, both with and without nutrient amendment. Chemical oxidation mobilized SOM into the liquid phase, producing dissolved organic carbon (DOC) concentrations 8-16 times higher than the untreated field sample. Higher aqueous concentrations of nitrogen and phosphorous species were also observed following oxidation; NH4(+) increased 14-172 times. During the bioremediation phase, dissolved carbon and nutrient species were utilized for microbial growth-yielding DOC concentrations similar to field sample levels within 56d of incubation. In the absence of nutrient amendment, the highest microbial respiration rates were correlated with higher availability of nitrogen and phosphorus species mobilized by oxidation. Significant diesel degradation was only observed following nutrient amendment, implying that nutrients mobilized by chemical oxidation can increase microbial activity but are insufficient for bioremediation. While all bioremediation occurred in the first 28d of incubation in the biotic control microcosm with nutrient amendment, biodegradation continued throughout 187d of incubation following chemical oxidation, suggesting that chemical treatment also affects the desorption of organic contaminants from SOM. Overall, results indicate that biodegradation of DOC, as an alternative substrate to diesel, and biological utilization of mobilized nutrients have implications for the success of coupled ISCO and ISB treatments.

  20. Impact of chemical oxidation on indigenous bacteria and mobilization of nutrients and subsequent bioremediation of crude oil-contaminated soil.

    Science.gov (United States)

    Xu, Jinlan; Deng, Xin; Cui, Yiwei; Kong, Fanxing

    2016-12-15

    Fenton pre-oxidation provides nutrients to promote bioremediation. However, the effects of the indigenous bacteria that remain following Fenton oxidation on nutrient mobilization and subsequent bioremediation remain unclear. Experiments were performed with inoculation with native bacteria and foreign bacteria or without inoculation after four regimens of stepwise pre-oxidations. The effects of the indigenous bacteria remaining after stepwise oxidation on nutrient mobilization and subsequent bioremediation over 80 days were investigated. After stepwise Fenton pre-oxidation at a low H2O2 concentration (225×4), the remaining indigenous bacterial populations reached their peak (4.8±0.17×10(6)CFU/g), the nutrients were mobilized rapidly, and the subsequent bioremediation of crude oil was improved (biodegradation efficiency of 35%). However, after stepwise Fenton pre-oxidation at a high H2O2 concentration (450×4), only 3.6±0.16×10(3)CFU/g of indigenous bacteria remained, and the indigenous bacteria that degrade C15-C30 alkanes were inhibited. The nutrient mobilization was then highly limited, and only 19% of total petroleum hydrocarbon was degraded. Furthermore, the recovery period after the low H2O2 concentration stepwise Fenton pre-oxidation (225×4) was less than 20 days, which was 20-30 days shorter than with the other pre-oxidation treatments. Therefore, stepwise Fenton pre-oxidation at a low H2O2 concentration protects indigenous bacterial populations and improves the nutrient mobilization and subsequent bioremediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Responses of plant nutrient resorption to phosphorus addition in freshwater marsh of Northeast China.

    Science.gov (United States)

    Mao, Rong; Zeng, De-Hui; Zhang, Xin-Hou; Song, Chang-Chun

    2015-01-29

    Anthropogenic activities have increased phosphorus (P) inputs to most aquatic and terrestrial ecosystems. However, the relationship between plant nutrient resorption and P availability is still unclear, and much less is known about the underlying mechanisms. Here, we used a multi-level P addition experiment (0, 1.2, 4.8, and 9.6 g P m(-2) year(-1)) to assess the effect of P enrichment on nutrient resorption at plant organ, species, and community levels in a freshwater marsh of Northeast China. The response of nutrient resorption to P addition generally did not vary with addition rates. Moreover, nutrient resorption exhibited similar responses to P addition across the three hierarchical levels. Specifically, P addition decreased nitrogen (N) resorption proficiency, P resorption efficiency and proficiency, but did not impact N resorption efficiency. In addition, P resorption efficiency and proficiency were linearly related to the ratio of inorganic P to organic P and organic P fraction in mature plant organs, respectively. Our findings suggest that the allocation pattern of plant P between inorganic and organic P fractions is an underlying mechanism controlling P resorption processes, and that P enrichment could strongly influence plant-mediated biogeochemical cycles through altered nutrient resorption in the freshwater wetlands of Northeast China.

  2. Functional compatibility in cucumber mycorrhizas in terms of plant growth performance and foliar nutrient composition.

    Science.gov (United States)

    Ravnskov, S; Larsen, J

    2016-09-01

    Functional compatibility in cucumber mycorrhizas in terms of plant and fungal growth, and foliar nutrient composition from all possible combinations of six cucumber varieties and three species of arbuscular mycorrhizal (AM) fungi was evaluated. Measurements of foliar nutrient composition included N, P, K, Mg, Ca, Na, Fe, Zn, Mn and Cu. Growth of AM fungi was measured in terms of root colonisation, as examined with microscopy and the AM fungus biomarker fatty acid 16:1ω5 from both phospholipids and neutral lipids. Different responses of plant growth and foliar nutrient profiles were observed for the different AM symbioses examined. The AM fungus Claroideoglomus claroideum caused growth depression in association with four out of six cucumber varieties; Rhizophagus irregularis caused growth promotion in one of six cucumber varieties; whereas Funneliformis mosseae had no effect on the growth performance of any of the cucumber varieties examined. All three AM fungi markedly altered host plant shoot nutrient composition, with the strongest contrast observed between cucumber-R. irregularis symbioses and non-mycorrhizal cucumber plants, independent of cucumber variety. On the other hand, AM fungal growth in roots differed between the three AM fungi, but was unaffected by host genotype. Strong build-up of storage lipids was observed for R. irregularis, which was more moderate in the two other AM fungi. In conclusion, strong differential responses of cucumber varieties to inoculation with different AM fungi in terms of growth and shoot nutrient composition revealed high functional diversity in AM symbioses in cucumber plants.

  3. Responses of plant nutrient resorption to phosphorus addition in freshwater marsh of Northeast China

    Science.gov (United States)

    Mao, Rong; Zeng, De-Hui; Zhang, Xin-Hou; Song, Chang-Chun

    2015-01-01

    Anthropogenic activities have increased phosphorus (P) inputs to most aquatic and terrestrial ecosystems. However, the relationship between plant nutrient resorption and P availability is still unclear, and much less is known about the underlying mechanisms. Here, we used a multi-level P addition experiment (0, 1.2, 4.8, and 9.6 g P m-2 year-1) to assess the effect of P enrichment on nutrient resorption at plant organ, species, and community levels in a freshwater marsh of Northeast China. The response of nutrient resorption to P addition generally did not vary with addition rates. Moreover, nutrient resorption exhibited similar responses to P addition across the three hierarchical levels. Specifically, P addition decreased nitrogen (N) resorption proficiency, P resorption efficiency and proficiency, but did not impact N resorption efficiency. In addition, P resorption efficiency and proficiency were linearly related to the ratio of inorganic P to organic P and organic P fraction in mature plant organs, respectively. Our findings suggest that the allocation pattern of plant P between inorganic and organic P fractions is an underlying mechanism controlling P resorption processes, and that P enrichment could strongly influence plant-mediated biogeochemical cycles through altered nutrient resorption in the freshwater wetlands of Northeast China.

  4. Microbial Communities in Danish Wastewater Treatment Plants with Nutrient Removal

    DEFF Research Database (Denmark)

    Mielczarek, Artur Tomasz

    that plants with return sludge Side-Stream Hydrolysis (SSH) instead of the normal anaerobic process tank tended to have significantly fewer unwanted GAOs in contrast to many plants with traditional mainstream anaerobic tank and thus it was proposed that this system might be an effective strategy of control...

  5. New Ways to Determine Plant Nutrient Deficiences Using Fast Spectroscopy

    DEFF Research Database (Denmark)

    van Maarschalkerweerd, Marie

    leaves. The method is specific for Cu, and the condition can be diagnosed so early that it is reversible. Paper III describes a method to diagnose P deficiency in barley plants and quantify P concentration in deficient plants. It was found that the I-step in the OJIP transient, which is the outcome...

  6. Continuous planting under a high density enhances the competition for nutrients among young Cunninghamia lanceolata saplings

    OpenAIRE

    Dong, Tingfa; Zhang, Yunxiang; Zhang,Yuanbin; Zhang, Sheng

    2016-01-01

    International audience; AbstractKey messageA high-density plantation inhibited growth and biomass accumulation of Cunninghamia lanceolata(Lamb.) Hook. saplings, as well as their photosynthesis. This inhibition was enhanced in a soil that had been previously planted with the same species. The main factors limiting photosynthesis and growth were leaf-level irradiance and nutrient availability, mainly of P and Mg.ContextThe planting density and continuous planting greatly affect the photosynthes...

  7. SOIL-PLANT NUTRIENT INTERACTIONS IN TWO MANGROVE AREAS AT SOUTHERN BRAZIL

    OpenAIRE

    Ana Paula Lang Martins Madi; Maria Regina Torres Boeger; Carlos Bruno Reissmann; Kelly Geronazzo Martins

    2015-01-01

    ABSTRACTMangrove forests have a simple architecture. They shelter a few number of arboreal species that grow in a saline environment subject to tidal activity. The research objective was to evaluate possible interactions between physical-chemical soil attributes and plant-leaf nutrient concentrations of different mangrove species. Different mangrove species growing in the same soil, and the same mangrove species growing in two different soil classes were evaluated as to their leaf nutrient co...

  8. Nutrient Release, Plant Nutrition, and Potassium Leaching from Polymer-Coated Fertilizer

    OpenAIRE

    Henrique Bley; Clesio Gianello; Lenio da Silva Santos; Lisiane Priscila Roldão Selau

    2017-01-01

    ABSTRACT The increase in food consumption and limitations in food production areas requires improved fertilizer efficiency. Slow- or controlled-release fertilizers are an alternative for synchronizing nutrient availability with the plant demands, reducing losses to the environment. The aim of this study was to evaluate the efficacy of polymer-coated KCl compared with conventional KCl. The products were incubated in soil under controlled conditions to evaluate the time required for nutrient re...

  9. Herbivores, the Functional Diversity of Plants Species, and the Cycling of Nutrients in Ecosystems

    Science.gov (United States)

    Pastor; Cohen

    1997-06-01

    Numerous investigators have suggested that herbivores almost always increase rates of nutrient and energy flow through terrestrial ecosystems by returning to the soil fecal material and urine with faster turnover rate than shed plant litter. These previous theories and models always treat the producer compartment as a homogenous pool. Essentially, they assume that consumers feed through a pureed cream of vegetable soup. However, many field observations and experiments have shown that consumers feed selectively (i.e., in a cafeteria) and that consumer choice is made on the same chemical basis that determines decomposition rates. Plants that are preferred food sources often have higher nutrient content, higher growth rates, and faster decomposition rates. As consumption reduces dominance of these species in favor of unpreferred species with slower decomposition, rates of nutrient cycling and energy flow should therefore decline. We analyze a model in which the consumer is given a choice among producers that vary in nutrient uptake rates, rates of nutrient return to decomposers, and consumer preference, and which is parameterized for plants and consumers characteristic of boreal regions. In this model, in an open, well-mixed system with one consumer and two such producers, the nutrient/energy flow will not exceed that of a system without the consumer. If the consumer has a choice between two such producers, it must choose one plant over the other at a greater ratio than that between the two plants in uptake and decay rates. In contrast, in a closed system the consumer must be less selective to coexist with the two plants. The system behavior is determined by the level of nutrient return through the consumer and the differences between the plants in nutrient uptake rates and consumer preference. Species richness affects properties of this model system to the extent that species are functionally distinct (i.e., have different rate constants) in a multivariate space of

  10. Are ant feces nutrients for plants? A metabolomics approach to elucidate the nutritional effects on plants hosting weaver ants

    DEFF Research Database (Denmark)

    Vidkjær, Nanna Hjort; Wollenweber, Bernd; Gislum, René

    2015-01-01

    interactions involving other ant species that have demonstrated the transfer of nutrients from ants to plants. In this 7-months study, a GC–MS-based metabolomics approach along with an analysis of total nitrogen and carbon levels was used to study metabolic changes in ant-hosting Coffea arabica plants compared......Weaver ants (genus Oecophylla) are tropical carnivorous ant species living in high numbers in the canopies of trees. The ants excrete copious amounts of fecal matter on leaf surfaces, and these feces may provide nutrients to host trees. This hypothesis is supported by studies of ant-plant...... with control plants. The results showed elevated levels of total nitrogen, amino acids, fatty acids, caffeine, and secondary metabolites of the phenylpropanoid pathway in leaves from ant-hosting plants. Minor effects were observed for sugars, whereas little or no effect was observed for organic acids, despite...

  11. Scaling plant nitrogen use and uptake efficiencies in response to nutrient addition in peatlands.

    Science.gov (United States)

    Iversen, Colleen M; Bridgham, Scott D; Kellogg, Laurie E

    2010-03-01

    Nitrogen (N) is the primary growth-limiting nutrient in many terrestrial ecosystems, and therefore plant production per unit N taken up (i.e., N use efficiency, NUE) is a fundamentally important component of ecosystem function. Nitrogen use efficiency comprises two components: N productivity (A(N), plant production per peak biomass N content) and the mean residence time of N in plant biomass (MRT(N)). We utilized a five-year fertilization experiment to examine the manner in which increases in N and phosphorus (P) availability affected plant NUE at multiple biological scales (i.e., from leaf to community level). We fertilized a natural gradient of nutrient-limited peatland ecosystems in the Upper Peninsula of Michigan, USA, with 6 g N x m(-2) x yr(-1), 2 g P x m(-2) x yr(-1), or a combination of N and P. Our objectives were to determine how changes in carbon and N allocation within a plant to leaf and woody tissue and changes in species composition within a community, both above- and belowground, would affect (1) NUE; (2) the adaptive trade-off between the components of NUE; (3) the efficiency with which plants acquired N from the soil (N uptake efficiency); and (4) plant community production per unit soil N availability (N response efficiency, NRE). As expected, N and P addition generally increased aboveground production and N uptake. In particular, P availability strongly affected the way in which plants took up and used N. Nitrogen use efficiency response to nutrient addition was not straightforward. Nitrogen use efficiency differed between leaf and woody tissue, among species, and across the ombrotrophic-minerotrophic gradient because plants and communities were adapted to maximize either A(N) or MRT(N), but not both concurrently. Increased N availability strongly decreased plant and community N uptake efficiency, while increased P availability increased N uptake efficiency, particularly in a nitrogen-fixing shrub. Nitrogen uptake efficiency was more important

  12. Nutrient dynamics and plant assemblages of Macrotermes falciger mounds in a savanna ecosystem

    Science.gov (United States)

    Muvengwi, Justice; Ndagurwa, Hilton G. T.; Nyenda, Tatenda; Mbiba, Monicah

    2016-10-01

    Termites through mound construction and foraging activities contribute significantly to carbon and nutrient fluxes in nutrient-poor savannas. Despite this recognition, studies on the influence of termite mounds on carbon and nitrogen dynamics in sub-tropical savannas are limited. In this regard, we examined soil nutrient concentrations, organic carbon and nitrogen mineralization in incubation experiments in mounds of Macrotermes falciger and surrounding soils of sub-tropical savanna, northeast Zimbabwe. We also addressed whether termite mounds altered the plant community and if effects were similar across functional groups i.e. grasses, forbs or woody plants. Mound soils had significantly higher silt and clay content, pH and concentrations of calcium (Ca), magnesium (Mg), potassium (K), organic carbon (C), ammonium (NH4+) and nitrate (NO3-) than surrounding soils, with marginal differences in phosphorus (P) and sodium (Na) between mounds and matrix soils. Nutrient enrichment increased by a factor ranging from 1.5 for C, 4.9 for Mg up to 10.3 for Ca. Although C mineralization, nitrification and nitrification fraction were similar between mounds and matrix soils, nitrogen mineralization was elevated on mounds relative to surrounding matrix soils. As a result, termite mounds supported unique plant communities rich and abundant in woody species but less diverse in grasses and forbs than the surrounding savanna matrix in response to mound-induced shifts in soil parameters specifically increased clay content, drainage and water availability, nutrient status and base cation (mainly Ca, Mg and Na) concentration. In conclusion, by altering soil properties such as texture, moisture content and nutrient status, termite mounds can alter the structure and composition of sub-tropical savanna plant communities, and these results are consistent with findings in other savanna systems suggesting that increase in soil clay content, nutrient status and associated changes in the plant

  13. Controls over nutrient flow through plants and microbes in Arctic tundra. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schimel, J.

    1994-02-01

    Ecosystem productivity in the Arctic is strongly controlled by N availability to plants. Thus, disturbances to the Arctic system are likely to have their greatest impacts by altering the supply of nutrients to plants. Thus, to understand the dynamics of Arctic tundra, a complete understanding of the controls on N cycling in tundra soils is necessary. This project focused on understanding nutrient dynamics in arctic tussock tundra, specifically evaluating the role of microbial uptake and competition for nutrients as a control on plant N-uptake. The project consisted of several major components: Short- and long-term partitioning of NH{sub 4}{sup +} in tussock tundra (1990--1991); Measurement of NH{sub 4}{sup +} uptake rates by Eriophorum vaginatum and by soil microbes; Determination of microbial NH{sub 4}{sup +} and NO{sub 3}{minus} uptake kinetics; and Determination of the partitioning of NH{sub 4}{sup +} and amino acids between E. vaginatum and soil microbes.

  14. Nematodes enhance plant growth and nutrient uptake under C and N-rich conditions

    Science.gov (United States)

    Gebremikael, Mesfin T.; Steel, Hanne; Buchan, David; Bert, Wim; de Neve, Stefaan

    2016-09-01

    The role of soil fauna in crucial ecosystem services such as nutrient cycling remains poorly quantified, mainly because of the overly reductionistic approach adopted in most experimental studies. Given that increasing nitrogen inputs in various ecosystems influence the structure and functioning of soil microbes and the activity of fauna, we aimed to quantify the role of the entire soil nematode community in nutrient mineralization in an experimental set-up emulating nutrient-rich field conditions and accounting for crucial interactions amongst the soil microbial communities and plants. To this end, we reconstructed a complex soil foodweb in mesocosms that comprised largely undisturbed native microflora and the entire nematode community added into defaunated soil, planted with Lolium perenne as a model plant, and amended with fresh grass-clover residues. We determined N and P availability and plant uptake, plant biomass and abundance and structure of the microbial and nematode communities during a three-month incubation. The presence of nematodes significantly increased plant biomass production (+9%), net N (+25%) and net P (+23%) availability compared to their absence, demonstrating that nematodes link below- and above-ground processes, primarily through increasing nutrient availability. The experimental set-up presented allows to realistically quantify the crucial ecosystem services provided by the soil biota.

  15. Nematodes enhance plant growth and nutrient uptake under C and N-rich conditions

    Science.gov (United States)

    Gebremikael, Mesfin T.; Steel, Hanne; Buchan, David; Bert, Wim; De Neve, Stefaan

    2016-01-01

    The role of soil fauna in crucial ecosystem services such as nutrient cycling remains poorly quantified, mainly because of the overly reductionistic approach adopted in most experimental studies. Given that increasing nitrogen inputs in various ecosystems influence the structure and functioning of soil microbes and the activity of fauna, we aimed to quantify the role of the entire soil nematode community in nutrient mineralization in an experimental set-up emulating nutrient-rich field conditions and accounting for crucial interactions amongst the soil microbial communities and plants. To this end, we reconstructed a complex soil foodweb in mesocosms that comprised largely undisturbed native microflora and the entire nematode community added into defaunated soil, planted with Lolium perenne as a model plant, and amended with fresh grass-clover residues. We determined N and P availability and plant uptake, plant biomass and abundance and structure of the microbial and nematode communities during a three-month incubation. The presence of nematodes significantly increased plant biomass production (+9%), net N (+25%) and net P (+23%) availability compared to their absence, demonstrating that nematodes link below- and above-ground processes, primarily through increasing nutrient availability. The experimental set-up presented allows to realistically quantify the crucial ecosystem services provided by the soil biota. PMID:27605154

  16. Plant Size and Competitive Dynamics along Nutrient Gradients.

    Science.gov (United States)

    Goldberg, Deborah E; Martina, Jason P; Elgersma, Kenneth J; Currie, William S

    2017-08-01

    Resource competition theory in plants has focused largely on resource acquisition traits that are independent of size, such as traits of individual leaves or roots or proportional allocation to different functions. However, plants also differ in maximum potential size, which could outweigh differences in module-level traits. We used a community ecosystem model called mondrian to investigate whether larger size inevitably increases competitive ability and how size interacts with nitrogen supply. Contrary to the conventional wisdom that bigger is better, we found that invader success and competitive ability are unimodal functions of maximum potential size, such that plants that are too large (or too small) are disproportionately suppressed by competition. Optimal size increases with nitrogen supply, even when plants compete for nitrogen only in a size-symmetric manner, although adding size-asymmetric competition for light does substantially increase the advantage of larger size at high nitrogen. These complex interactions of plant size and nitrogen supply lead to strong nonlinearities such that small differences in nitrogen can result in large differences in plant invasion success and the influence of competition along productivity gradients.

  17. Standard sampling method of Longkong leaf for evaluation of plant nutrient status

    Directory of Open Access Journals (Sweden)

    Sae-lim, M.

    2005-05-01

    Full Text Available Leaf analysis is a tool for effective fertilizer recommendations in fruit trees. To achieve this goal, suitable leaf sampling method is a very important step. This study aimed to investigate leaf age, leaflet from different compound leaf positions and number of trees to be sampled as a representative sample for plant nutrient status of Longkong (Aglaia dookkoo Griff. tree. The middle pair of leaflets from the 1st, 2nd, 3rd, and 4th compound leaves from growing twigs at the lower canopy of Longkong trees were separately sampled and the following nutrients were determined: nitrogen (N, phosphorus (P, potassium (K, calcium (Ca and magnesium (Mg. The effect of soil fertility management and leaf age collected from twigs flushed at flowering and post harvest stages on nutrient concentration was investigated. Results showed that concentrations of plant nutrients in leaflets collected from different compound leaf positions were not significantly different. The leaf nutrient concentration depended on soil fertility management, higher fertilizer input resulting in higher leaf nutrient concentration. As leaf age increased, concentrations of N, P and K tended to decrease. In contrast, concentrations of Ca and Mg increased with leaf age. However, concentrations of most nutrients showed minimum variation with leaf aged 3-6 months. It is, thus, suggested that the middle pair leaflet of the 2nd compound leaf position aged 3-6 months of the lower twig should be sampled at post harvest stage from 25-35 trees to be used as a composite sample for plant nutrient analysis.

  18. Hydrological management for improving nutrient assimilative capacity in plant-dominated wetlands: A modelling approach.

    Science.gov (United States)

    Xu, Zhihao; Yang, Zhifeng; Yin, Xinan; Cai, Yanpeng; Sun, Tao

    2016-07-15

    Wetland eutrophication is a global environmental problem. Besides reducing pollutant emissions, improving nutrient assimilative capacity in wetlands is also significant for preventing eutrophication. Hydrological management can improve nutrient assimilative capacity in wetlands through physical effects on the dilution capacity of water body and ecological effects on wetland nutrient cycles. The ecological effects are significant while were rarely considered in previous research. This study focused on the ecological effects of hydrological management on two crucial nutrient removal processes, plant uptake and biological denitrification, in plant-dominated wetlands. A dual-objective optimization model for hydrological management was developed to improve wetland nitrogen and phosphorus assimilative capacities, using upstream reservoir release as water regulating measure. The model considered the interactions between ecological processes and hydrological cycles in wetlands, and their joint effects on nutrient assimilative capacity. Baiyangdian Wetland, the largest freshwater wetland in northern China, was chosen as a case study. The results found that the annual total assimilative capacity of nitrogen (phosphorus) was 4754 (493) t under the optimal scheme for upstream reservoir operation. The capacity of nutrient removal during the summer season accounted for over 80% of the annual total removal capacity. It was interesting to find that the relationship between water inflow and nutrient assimilative capacity in a plant-dominated wetland satisfied a dose-response relationship commonly describing the response of an organism to an external stressor in the medical field. It illustrates that a plant-dominated wetland shows similar characteristics to an organism. This study offers a useful tool and some fresh implications for future management of wetland eutrophication prevention.

  19. Biochar as carrier for plant nutrients and microorganisms - techniques of agro-activation

    Science.gov (United States)

    Schmidt, H.-P.

    2012-04-01

    The soil enhancing qualities of biochar are strongly linked to its influence on nutrient cycling dynamics, sorption dynamics and to changing habitat condition for soil fauna. But as shown in multiple studies, the addition of pure biochar to agricultural soils may provoke reduced plant growth caused by the immobilisation of plant nutrients. The very potent sorption dynamics of biochar makes it an effective carrier for plant nutrients and plant-root symbiotic microorganisms. At the Delinat-Institute, we tried sundry methods of charging biochars with organic and mineral plant nutrients as well as with microorganisms. This includes the use of biochar as bulk agent in aerobic composting, in malolactic fermentation and as treatment for liquid manure, but also formulations of mineral carbon-fertilizers. Those biochar products are tested in pot and also large scale field trials. Results and experiences of these trials as well as different activation methods will be explained. A short overview of industrial designing of biochar based products will be given.

  20. Finding the harvesting frequency to maximize nutrient removal in a constructed wetland dominated by submerged aquatic plants

    NARCIS (Netherlands)

    Verhofstad, M.J.J.M.; Poelen, M.D.M.; Van Kempen, M.M.L.; Bakker, E.S.; Smolders, A.J.P.

    2017-01-01

    Water quality is still poor in many freshwater ecosystems around the world as a result of anthropogenic nutrient loading. Constructed wetlands can be used to remove excess nutrients. In these wetlands, helophytes or free floating aquatic plants are traditionally used to absorb the nutrients. The

  1. Evaluation of the nutrient status of wheat plants

    NARCIS (Netherlands)

    Kostic, M.; Dijkshoorn, W.; Wit, de C.T.

    1967-01-01

    The balance of the principal ionic constituents in plants is reviewed in relation to the requirements for each of the elements, and for total accumulation as reflected in the total cation content (C), the inorganic anion conent (A) and the organic anion content (C-A). The balance in young wheat plan

  2. Nutrient considerations for Plants grown under Spaceflight conditions.

    Science.gov (United States)

    Levine, H. G.; Krikorian, A. D.

    We present here results on the analysis of 100 mL medium samples extracted from sterilized floral foam Smithers-Oasis Kent OH used to support the growth of both dicotyledonous Haplopappus gracilis n 75 and monocotyledonous Hemerocallis cv Autumn Blaze n 25 aseptic plants in NASA s Plant Growth Unit PGU during the 5-day CHROMEX-01 Space Shuttle flight March 1989 STS-29 At recovery the medium remaining within each of the five foam blocks for both the space flight and ground control experiments was extracted under vacuum filtered and subjected to elemental analyses Concentration levels of some elements remained the same while some decreased and others increased A unique aspect of this experiment was that all plants were either aseptic tissue culture generated plantlets or sterile seedling clones and the design of the PGU facilitated the maintenance of asepsis throughout the mission confirmed by post-flight microbial sampling This permitted the elimination of microbial considerations in the interpretation of the data The significance of these findings for growing plants in altered gravity environments is discussed

  3. Kareel plant: A natural source of medicines and nutrients

    Directory of Open Access Journals (Sweden)

    Ravi K Upadhyay

    2011-01-01

    Full Text Available Capparis decidua or kareel is an indigenous medicinal plant of India having large biodiversity in different north-western states of India. The young flower bud and fruits are used to make pickles while caper berries are used as vegetable. Plant has its wider utility in traditional folk medicine and is used as ailments to relieve variety of pains or aches such as toothache, cough and asthma heal. Plant contains few important secondary metabolites such as quercetin which act as melanogenesis stimulator and also increase tyrosinase protein expression. Capparis sp. seeds contain lectin that exhibit potent anti HIV-1 reverse transcriptase inhibition activity and also inhibits proliferation of hepatoma HepG2 and breast cancer MCF-7 cells. It shows anti-rheumatic, anti-diabitic, anti-arthritis and anti-gout agent. C. decidua contains generous quantities of alkaloids, fatty acids, terpenes, vitamins, fibre and oils that show greater medicinal and nutritive value. It also contains saccharides, glycosides, flavonoids, volatile oils, sterols and steroids, which showed multiple pharmacological effects such as anti-inflammatory, odynolysis, anti-fungus, hepatoprotective effect, hypoglycemic activity, anti-oxidation, anti-hyperlipemia, anti-coagulated blood, smooth muscle stimulation, anti-stress reaction. Cadabicine an alkaloid that occurs in leaves shows anti-parasitic activity, while root bark and pulp are used to kill helminthes. Due to enzymatic inhibition plant extract shows the ability to control Leishmania major and L. infantum, L. donovani, L. braziliensis, Crithidia fasciculata and Herpetomonas muscarum infection. In the present review article both medicinal and nutraceutical properties of C decidua have been described in detail and special emphasis is given on its sustainable use of plant and its conservation in natural habitat.

  4. Improving Lowland Rice (O. sativa L. cv. MR219) Plant Growth Variables, Nutrients Uptake, and Nutrients Recovery Using Crude Humic Substances.

    Science.gov (United States)

    Palanivell, Perumal; Ahmed, Osumanu Haruna; Ab Majid, Nik Muhamad; Jalloh, Mohamadu Boyie; Susilawati, Kasim

    2015-01-01

    High cation exchange capacity and organic matter content of crude humic substances from compost could be exploited to reduce ammonia loss from urea and to as well improve rice growth and soil chemical properties for efficient nutrients utilization in lowland rice cultivation. Close-dynamic air flow system was used to determine the effects of crude humic substances on ammonia volatilization. A pot experiment was conducted to determine the effects of crude humic substances on rice plant growth, nutrients uptake, nutrients recovery, and soil chemical properties using an acid soil mixed with three rates of crude humic substances (20, 40, and 60 g pot(-1)). Standard procedures were used to evaluate rice plant dry matter production, nutrients uptake, nutrients recovery, and soil chemical properties. Application of crude humic substances increased ammonia volatilization. However, the lowest rate of crude humic substances (20 g pot(-1)) significantly improved total dry matter, nutrients uptake, nutrients recovery, and soil nutrients availability compared with crude humic substances (40 and 60 g pot(-1)) and the normal fertilization. Apart from improving growth of rice plants, crude humic substances can be used to ameliorate acid soils in rice cultivation. The findings of this study are being validated in our ongoing field trials.

  5. Improving Lowland Rice (O. sativa L. cv. MR219 Plant Growth Variables, Nutrients Uptake, and Nutrients Recovery Using Crude Humic Substances

    Directory of Open Access Journals (Sweden)

    Perumal Palanivell

    2015-01-01

    Full Text Available High cation exchange capacity and organic matter content of crude humic substances from compost could be exploited to reduce ammonia loss from urea and to as well improve rice growth and soil chemical properties for efficient nutrients utilization in lowland rice cultivation. Close-dynamic air flow system was used to determine the effects of crude humic substances on ammonia volatilization. A pot experiment was conducted to determine the effects of crude humic substances on rice plant growth, nutrients uptake, nutrients recovery, and soil chemical properties using an acid soil mixed with three rates of crude humic substances (20, 40, and 60 g pot−1. Standard procedures were used to evaluate rice plant dry matter production, nutrients uptake, nutrients recovery, and soil chemical properties. Application of crude humic substances increased ammonia volatilization. However, the lowest rate of crude humic substances (20 g pot−1 significantly improved total dry matter, nutrients uptake, nutrients recovery, and soil nutrients availability compared with crude humic substances (40 and 60 g pot−1 and the normal fertilization. Apart from improving growth of rice plants, crude humic substances can be used to ameliorate acid soils in rice cultivation. The findings of this study are being validated in our ongoing field trials.

  6. Maternal control of nutrient allocation in plant seeds by genomic imprinting.

    Science.gov (United States)

    Costa, Liliana M; Yuan, Jing; Rouster, Jacques; Paul, Wyatt; Dickinson, Hugh; Gutierrez-Marcos, Jose F

    2012-01-24

    Imprinted genes are commonly expressed in mammalian placentas and in plant seed endosperms, where they exhibit preferential uniparental allelic expression. In mammals, imprinted genes directly regulate placental function and nutrient distribution from mother to fetus; however, none of the >60 imprinted genes thus far reported in plants have been demonstrated to play an equivalent role in regulating the flow of resources to the embryo. Here we show that imprinted Maternally expressed gene1 (Meg1) in maize is both necessary and sufficient for the establishment and differentiation of the endosperm nutrient transfer cells located at the mother:seed interface. Consistent with these findings, Meg1 also regulates maternal nutrient uptake, sucrose partitioning, and seed biomass yield. In addition, we generated an imprinted and nonimprinted synthetic Meg1 ((syn)Meg1) dosage series whereby increased dosage and absence of imprinting both resulted in an unequal investment of maternal resources into the endosperm. These findings highlight dosage regulation by genomic imprinting as being critical for maintaining a balanced distribution of maternal nutrients to filial tissues in plants, as in mammals. However, unlike in mammals, Meg1 is a maternally expressed imprinted gene that surprisingly acts to promote rather than restrict nutrient allocation to the offspring.

  7. Embedded mobile farm robot for identification of diseased plants

    Science.gov (United States)

    Sadistap, S. S.; Botre, B. A.; Pandit, Harshavardhan; Chandrasekhar; Rao, Adesh

    2013-07-01

    This paper presents the development of a mobile robot used in farms for identification of diseased plants. It puts forth two of the major aspects of robotics namely automated navigation and image processing. The robot navigates on the basis of the GPS (Global Positioning System) location and data obtained from IR (Infrared) sensors to avoid any obstacles in its path. It uses an image processing algorithm to differentiate between diseased and non-diseased plants. A robotic platform consisting of an ARM9 processor, motor drivers, robot mechanical assembly, camera and infrared sensors has been used. Mini2440 microcontroller has been used wherein Embedded linux OS (Operating System) is implemented.

  8. Adaptive radiation with regard to nutrient sequestration strategies in the carnivorous plants of the genus Nepenthes.

    Science.gov (United States)

    Pavlovič, Andrej

    2012-02-01

    Carnivorous pitcher plants of the genus Nepenthes have evolved a great diversity of pitcher morphologies. Selective pressures for maximizing nutrient uptake have driven speciation and diversification of the genus in a process known as adaptive radiation. This leads to the evolution of pitchers adapted to specific and often bizarre source of nutrients, which are not strictly animal-derived. One example is Nepenthes ampullaria with unusual growth pattern and pitcher morphology what enables the plant to capture a leaf litter from the canopy above. We showed that the plant benefits from nitrogen uptake by increased rate of photosynthesis and growth what may provide competitive advantage over others co-habiting plants. A possible impact of such specialization toward hybridization, an important mechanism in speciation, is discussed.

  9. How do plants respond to nutrient shortage by biomass allocation?

    Science.gov (United States)

    Hermans, Christian; Hammond, John P; White, Philip J; Verbruggen, Nathalie

    2006-12-01

    Plants constantly sense the changes in their environment; when mineral elements are scarce, they often allocate a greater proportion of their biomass to the root system. This acclimatory response is a consequence of metabolic changes in the shoot and an adjustment of carbohydrate transport to the root. It has long been known that deficiencies of essential macronutrients (nitrogen, phosphorus, potassium and magnesium) result in an accumulation of carbohydrates in leaves and roots, and modify the shoot-to-root biomass ratio. Here, we present an update on the effects of mineral deficiencies on the expression of genes involved in primary metabolism in the shoot, the evidence for increased carbohydrate concentrations and altered biomass allocation between shoot and root, and the consequences of these changes on the growth and morphology of the plant root system.

  10. Nutrients of Topsoil for Sugarcane Planting in Xinping County of Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    Jiabin; MA; Wanghai; TIAN; Shunfa; LONG; Huazhen; LI; Long; SU; Zhitao; YIN; Yuanyuan; GAO

    2014-01-01

    To provide reference for fertilizer application of sugarcane planting in Xinping County,this paper analyzed nutrient content of topsoil according to the nutrient indicators established in the Second Soil Census. The results show that 51. 76% soil in sugarcane planting area of Xinping County is faintly acid,50. 88% soil has relatively low organic matter,45. 88% soil lacks alkali-hydrolyzable nitrogen( N),26. 47% soil lacks phosphorus( P),50. 29% soil lacks potassium( K),37. 14% soil lacks sulfur( S),12. 86% soil lacks magnesium( Mg),10% soil lacks manganese( Mn),and 31. 43% soil lacks zinc( Zn). In the sugarcane production,it is required to pay attention to increase of application of organic fertilizer,to foster soil fertility,supplement boron fertilizer,to keep balance of soil nutrients.

  11. The effect of AMF suppression on plant species composition in a nutrient-poor dry grassland.

    Science.gov (United States)

    Dostálek, Tomáš; Pánková, Hana; Münzbergová, Zuzana; Rydlová, Jana

    2013-01-01

    Arbuscular mycorrhizal fungi (AMF) are expected to be one of the key drivers determining the diversity of natural plant communities, especially in nutrient-poor and dry habitats. Several previous studies have explored the importance of AMF for the composition of plant communities in various types of habitats. Surprisingly, studies of the role of AMF in nutrient-poor dry grassland communities dominated by less mycotrophic plant species are still relatively rare. We present the results of a 3-year study in which a plant community in a species-rich dry grassland was subjected to the fungicide carbendazim to suppress AMF colonization. We tested the effect of the fungicide on the following parameters: the plant species composition; the number of plant species; the cover of the rare, highly mycorrhiza-dependent species Aster amellus; the cover of the dominant, less mycorrhiza-dependent species Brachypodium pinnatum; and the cover of graminoids and perennial forbs. In addition, we examined the mycorrhizal inoculation potential of the soil. We found that the suppression of AMF with fungicide resulted in substantial changes in plant species composition and significant decrease in species richness, the cover of A. amellus and the cover of perennial forbs. In contrast the species increasing their cover after fungicide application were graminoids--the C3 grasses B. pinnatum and Bromus erectus and the sedge Carex flacca. These species appear to be less mycorrhiza dependent. Moreover, due to their clonal growth and efficient nutrient usage, they are, most likely, better competitors than perennial forbs under fungicide application. Our results thus suggest that AMF are an essential part of the soil communities supporting a high diversity of plant species in species-rich dry grasslands in nutrient-poor habitats. The AMF are especially important for the maintenance of the populations of perennial forbs, many of which are rare and endangered in the area.

  12. Effect of temperature and nutrients on the growth and development of seedlings of an invasive plant.

    Science.gov (United States)

    Skálová, Hana; Moravcová, Lenka; Dixon, Anthony F G; Kindlmann, P; Pyšek, Petr

    2015-04-28

    Plant species distributions are determined by the response of populations to regional climates; however, little is known about how alien plants that arrive in central Europe from climatically warmer regions cope with the temperature conditions at the early stage of population development. Ambrosia artemisiifolia (common ragweed) is an invasive annual plant causing considerable health and economic problems in Europe. Although climate-based models predict that the whole of the Czech Republic is climatically suitable for this species, it is confined to the warmest regions. To determine the factors possibly responsible for its restricted occurrence, we investigated the effects of temperature and nutrient availability on its seedlings. The plants were cultivated at one of seven temperature regimes ranging from 10 to 34 °C, combined with three nutrient levels. The data on the rate of leaf development were used to calculate the lower developmental threshold (LDT, the temperature, in °C, below which development ceases), the sum of effective temperatures (SET, the amount of heat needed to complete a developmental stage measured in degree days above LDT) and width of the thermal window. The rate of development decreased with decrease in temperature and nutrient supply. Besides this, the decrease in the availability of nutrients resulted in decreased LDT, increased SET and wider thermal window. The dependence of LDT and SET on the availability of nutrients contradicts the concept that thermal constants do not vary. Our results highlight temperature as the main determinant of common ragweed's distribution and identify nutrient availability as a factor that results in the realized niche being smaller than the fundamental niche; both of these need to be taken into account when predicting the future spread of A. artemisiifolia.

  13. Combating Human Micronutrient Deficiencies through Soil Management Practices that Enhance Bioavailability of Nutrients to Plants

    Science.gov (United States)

    O'Meara, Mary

    2009-01-01

    Micronutrient malnutrition affects the health and well being of 3 billion people globally. Identifying means to improve the micronutrient density in the edible portions of crops is an important way to combat nutrient deficiencies. By studying how plants obtain micronutrients from the soil, we can develop methods to enhance uptake. Although more…

  14. Benchmarking biological nutrient removal in wastewater treatment plants: influence of mathematical model assumptions

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Gernaey, Krist V.; Jeppsson, Ulf

    2012-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant...

  15. Relative quantitative RT-PCR to study the expression of plant nutrient transporters in arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, S.H.

    2001-01-01

    The influence of arbuscular mycorrhizal fungi (AMF) on the expression of plant nutrient transporters was studied using a relative. quantitative reverse-transcription polymerase chain-reaction (RQRT-PCR) technique. Reverse-transcribed 18S rRNA was used to standardize the treatments. The technique...

  16. Interactions between plant growth and soil nutrient cycling under elevated CO2: a meta-analysis

    NARCIS (Netherlands)

    Graaff, de M.A.; Groenigen, van K.J.; Six, J.; Hungate, B.; Kessel, van C.

    2006-01-01

    free air carbon dioxide enrichment (FACE) and open top chamber (OTC) studies are valuable tools for evaluating the impact of elevated atmospheric CO2 on nutrient cycling in terrestrial ecosystems. Using meta-analytic techniques, we summarized the results of 117 studies on plant biomass production, s

  17. Combating Human Micronutrient Deficiencies through Soil Management Practices that Enhance Bioavailability of Nutrients to Plants

    Science.gov (United States)

    O'Meara, Mary

    2009-01-01

    Micronutrient malnutrition affects the health and well being of 3 billion people globally. Identifying means to improve the micronutrient density in the edible portions of crops is an important way to combat nutrient deficiencies. By studying how plants obtain micronutrients from the soil, we can develop methods to enhance uptake. Although more…

  18. Plant rhizosphere effects on metal mobilization and transport. 1998 annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Fan, T.W.M.

    1998-06-01

    'Information on the mechanism of how plants mobilize, uptake, and metabolize metal ions is very limited. Especially deficient is the understanding of these processes involving pollutant metal ions and interactions among these ions. Based on the current knowledge regarding nutrient ions, it is clear that elucidation of rhizospheric processes such as exudation of organic ligands by plant roots and plant metabolism/adaptation involving these biogenic chelators is critically important. A mechanistic insight into these processes will advance knowledge in microbe-plant host interactions and how metal ions are mobilized, immobilized, and sequestered by these interactions. This, in turn, is essential to applications such as phytobioremediation and microbioremediation of metal ion pollution. Root exudation also serves many other important rhizosphere functions including energy supply for microbial degradation of organic pollutants, structuring of microbial community, and the formation of soil humic materials which are considered to be a major sink for both organic and inorganic pollutants. How root exudates function is critically dependent on the chemical nature of exudate components. Therefore, a comprehensive characterization of all major exudate components, regardless of their chemical class, should facilitate the development and implementation of bioremediation for both organic and inorganic pollutants. Therefore, the objectives of this project are: (1) To obtain a comprehensive composition of major organic components in plant root exudates as a function of different metal ions; (2) To examine plant metabolic response(s) to these metal ion treatments, with emphasis on biosynthetic pathways of organic ligands; and (3) To investigate the effect(s) of soil microbial (e.g. mycorrhizae) association on (1) and (2).'

  19. Plant species effects on soil nutrients and chemistry in arid ecological zones.

    Science.gov (United States)

    Johnson, Brittany G; Verburg, Paul S J; Arnone, John A

    2016-09-01

    The presence of vegetation strongly influences ecosystem function by controlling the distribution and transformation of nutrients across the landscape. The magnitude of vegetation effects on soil chemistry is largely dependent on the plant species and the background soil chemical properties of the site, but has not been well quantified along vegetation transects in the Great Basin. We studied the effects of plant canopy cover on soil chemistry within five different ecological zones, subalpine, montane, pinyon-juniper, sage/Mojave transition, and desert shrub, in the Great Basin of Nevada all with similar underlying geology. Although plant species differed in their effects on soil chemistry, the desert shrubs Sarcobatus vermiculatus, Atriplex spp., Coleogyne ramosissima, and Larrea tridentata typically exerted the most influence on soil chemistry, especially amounts of K(+) and total nitrogen, beneath their canopies. However, the extent to which vegetation affected soil nutrient status in any given location was not only highly dependent on the species present, and presumably the nutrient requirements and cycling patterns of the plant species, but also on the background soil characteristics (e.g., parent material, weathering rates, leaching) where plant species occurred. The results of this study indicate that the presence or absence of a plant species, especially desert shrubs, could significantly alter soil chemistry and subsequently ecosystem biogeochemistry and function.

  20. Controls of bedrock geochemistry on soil and plant nutrients in Southeastern Utah

    Science.gov (United States)

    Neff, J.C.; Reynolds, R.; Sanford, R.L.; Fernandez, D.; Lamothe, P.

    2006-01-01

    The cold deserts of the Colorado Plateau contain numerous geologically and geochemically distinct sedimentary bedrock types. In the area near Canyonlands National Park in Southeastern Utah, geochemical variation in geologic substrates is related to the depositional environment with higher concentrations of Fe, Al, P, K, and Mg in sediments deposited in alluvial or marine environments and lower concentrations in bedrock derived from eolian sand dunes. Availability of soil nutrients to vegetation is also controlled by the formation of secondary minerals, particularly for P and Ca availability, which, in some geologic settings, appears closely related to variation of CaCO3 and Ca-phosphates in soils. However, the results of this study also indicate that P content is related to bedrock and soil Fe and Al content suggesting that the deposition history of the bedrock and the presence of P-bearing Fe and Al minerals, is important to contemporary P cycling in this region. The relation between bedrock type and exchangeable Mg and K is less clear-cut, despite large variation in bedrock concentrations of these elements. We examined soil nutrient concentrations and foliar nutrient concentration of grasses, shrubs, conifers, and forbs in four geochemically distinct field sites. All four of the functional plant groups had similar proportional responses to variation in soil nutrient availability despite large absolute differences in foliar nutrient concentrations and stoichiometry across species. Foliar P concentration (normalized to N) in particular showed relatively small variation across different geochemical settings despite large variation in soil P availability in these study sites. The limited foliar variation in bedrock-derived nutrients suggests that the dominant plant species in this dryland setting have a remarkably strong capacity to maintain foliar chemistry ratios despite large underlying differences in soil nutrient availability. ?? 2006 Springer Science

  1. Nutrient capital sequestration in pioneer plant communities on surface-mine spoil

    Energy Technology Data Exchange (ETDEWEB)

    Wade, G.L.

    1985-01-01

    Four pioneer plant communities on a surface-mine spoil were compared in terms of biomass production and nutrient capital sequestration. A chenopodium album-dominated community (Treatment 4) produced the greatest amount of biomass. Next were a community derived from a forest topsoil seed bank spread over mine spoil (Treatment 2), a seed bank community with common reclamation species seeded into it (Treatment 3), and a mix of grasses and Lespedeza commonly used in reclamation (Treatment 1). Amounts of nutrients sequestered in vegetation were not strictly proportional to biomass. Community nutrient contents were largely influenced by community biomass and the nutrient uptake characteristics of the species with most biomass. Significant changes in soil chemistry were found after one growing season. Addition of the reclamation mix of grasses and Lespedeza to the seed bank resulted in significantly fewer established native species. Native species lost their normal dominance and exhibited stunted growth and phenological delay in Treatment 3. Nutrient content niche, nutrient content niche share, and niche breadth (Levins; B) were calculated for important species in each community. Native species generally had reduced niche breadths and niche shares when reclamation species were added to the community. Community content niche, the sums of species content niches, varied between different types of pioneer communities.

  2. [Soil nutrients spatial variability and soil fertility suitability in Qujing tobacco-planting area].

    Science.gov (United States)

    Li, Qiang; Zhou, Ji-heng; Yang, Rong-sheng; Zhang, Zheng-yan; Xie, Yan; Zhang, Yi-yang; Huang, Kua-ke; Li, Wei

    2011-04-01

    By adopting GPS technique, 2088 sampling sites were installed in the tobacco-planting area of Qujing City, Yunnan Province, with 0-20 cm soil samples collected to determine their main nutrients contents. The overall characteristics and spatial variability of the tobacco soil nutrients were analyzed by classic statistics and geo-statistics, and the soil fertility suitability in planting tobacco was evaluated by the methods of fuzzy mathematics. In the study area, soil pH and soil organic matter, available S, and water-soluble Cl contents were appropriate, soil total N and alkalihydrolyzable N contents were too high, soil available K, Ca, Mg, Cu, Fe, Zn, Mo, and Mn contents were abundant, soil available P content was at medium level, while soil total P and K and available B contents were insufficient. All the nutrient indices presented anisotropic distribution, among which, the spatial variability of soil available P and B was mainly caused by random factors, and that of other nutrients was caused by the co-effects of structural and random factors. The spatial distribution map of soil fertility suitability index (SFI) showed that there was no the excellent grade region for tobacco-planting, good grade region accounted for 8.0%, general grade region accounted for 51.6%, moderate grade region accounted for 39.0%, and low grade region accounted for 1.4%.

  3. Identification and Control of Nutrient Removing Processes in Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Nielsen, Marinus K.; Madsen, Henrik; Carstensen, Niels Jacob

    1994-01-01

    Today the use of on-line control for wastewater treatment plants is very low. A main reason is the lack of quality of the data, and the fact that more sophisticated control strategies must be based on a model of the dynamics of the biological processes. This paper discusses the historical reasons...... for the limited use of modern control strategies for wastewater treatment plants. Today, however, on-line nutrient sensors are more reliable. In the present context the use of on-line monitored values of ammonia, nitrate and phosphate from a full scale plant are used as the background for discussing...

  4. Decomposition and nutrient release of leguminous plants in coffee agroforestry systems

    Directory of Open Access Journals (Sweden)

    Eduardo da Silva Matos

    2011-02-01

    Full Text Available Leguminous plants used as green manure are an important nutrient source for coffee plantations, especially for soils with low nutrient levels. Field experiments were conducted in the Zona da Mata of Minas Gerais State, Brazil to evaluate the decomposition and nutrient release rates of four leguminous species used as green manures (Arachis pintoi, Calopogonium mucunoides, Stizolobium aterrimum and Stylosanthes guianensis in a coffee agroforestry system under two different climate conditions. The initial N contents in plant residues varied from 25.7 to 37.0 g kg-1 and P from 2.4 to 3.0 g kg-1. The lignin/N, lignin/polyphenol and (lignin+polyphenol/N ratios were low in all residues studied. Mass loss rates were highest in the first 15 days, when 25 % of the residues were decomposed. From 15 to 30 days, the decomposition rate decreased on both farms. On the farm in Pedra Dourada (PD, the decomposition constant k increased in the order C. mucunoides < S. aterrimum < S. guianensis < A. pintoi. On the farm in Araponga (ARA, there was no difference in the decomposition rate among leguminous plants. The N release rates varied from 0.0036 to 0.0096 d-1. Around 32 % of the total N content in the plant material was released in the first 15 days. In ARA, the N concentration in the S. aterrimum residues was always significantly higher than in the other residues. At the end of 360 days, the N released was 78 % in ARA and 89 % in PD of the initial content. Phosphorus was the most rapidly released nutrient (k values from 0.0165 to 0.0394 d-1. Residue decomposition and nutrient release did not correlate with initial residue chemistry and biochemistry, but differences in climatic conditions between the two study sites modified the decomposition rate constants.

  5. Genetic Based Plant Resistance and Susceptibility Traits to Herbivory Influence Needle and Root Litter Nutrient Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Classen, Aimee T [ORNL; Chapman, Samantha K. [Smithsonian Environmental Research Center, Edgewater, MD; Whitham, Thomas G [Northern Arizona University; Hart, Stephen C [Northern Arizona University; Koch, George W [Northern Arizona University

    2007-01-01

    It is generally assumed that leaf and root litter decomposition have similar drivers and that nutrient release from these substrates is synchronized. Few studies have examined these assumptions, and none has examined how plant genetics (i.e., plant susceptibility to herbivory) could affect these relationships. Here we examine the effects of herbivore susceptibility and resistance on needle and fine root litter decomposition of pi on pine, Pinus edulis. The study population consists of individual trees that are either susceptible or resistant to herbivory by the pi on needle scale, Matsucoccus acalyptus, or the stem-boring moth, Dioryctria albovittella. Genetic analyses and experimental removals and additions of these insects have identified trees that are naturally resistant and susceptible to these insects. These herbivores increase the chemical quality of litter inputs and alter soil microclimate, both of which are important decomposition drivers. Our research leads to four major conclusions: Herbivore susceptibility and resistance effects on 1) needle litter mass loss and phosphorus (P) retention in moth susceptible and resistant litter are governed by microclimate, 2) root litter nitrogen (N) and P retention, and needle litter N retention are governed by litter chemical quality, 3) net nutrient release from litter can reverse over time, 4) root and needle litter mass loss and nutrient release are determined by location (above- vs. belowground), suggesting that the regulators of needle and root decomposition differ at the local scale. Understanding of decomposition and nutrient retention in ecosystems requires consideration of herbivore effects on above- and belowground processes and how these effects may be governed by plant genotype. Because an underlying genetic component to herbivory is common to most ecosystems of the world and herbivory may increase in climatic change scenarios, it is important to evaluate the role of plant genetics in affecting carbon and

  6. Dynamics of Nutrient Accumulation in Maize Plants Under Different Water and N Supply Conditions

    Institute of Scientific and Technical Information of China (English)

    SONG Hai-xing; LI Sheng-xiu

    2002-01-01

    The dynamics of accumulations of plant dry matter, nutrient uptake and N fertilizer recoverywere studied with different water and N supply, using summer maize (Zea mays L. var. Shandang) as an indi-cator crop. The total dry matter (including roots) and N, P, K uptake amounts were continuously increasedwith plant growth, and their accumulations with time during plant-growing period were shaped in S curves thatcould be described by exponential regression equations. Differentiating the regression equations fitting thecurves over time for first derivatives, the momentary rate was obtained of the dry matter and nutrient uptake.Results show that the dry matter and the nutrient uptake were not in the same rate at all time, but changedfrom one time to another. Usually, the rate increased rapidly at early stages, and gradually decreased afterreaching their peak. Of N, P and K, the uptake rate of N and K was higher, and their increase and decreasewere both fast while P was reversed. The time of the maximum absorptive rate appeared earlier for K, fol-lowed by N, and then by P. In any case, the maximum nutrient uptake rate appeared earlier than did the drymatter. The momentary N recovery rate was similar in trend to those of dry matter and N uptake, and its max-imum recovery rate occurred almost at the same time as its maximum uptake rate. Supplemental irrigationraised the cumulative and momentary rates of N. Although water and N supplies increased dry matter and nu-trient uptake rates, they did not alter their changing trends during the plant-growing period.

  7. Common mycorrhizal networks amplify competition by preferential mineral nutrient allocation to large host plants.

    Science.gov (United States)

    Weremijewicz, Joanna; Sternberg, Leonel da Silveira Lobo O'Reilly; Janos, David P

    2016-10-01

    Arbuscular mycorrhizal (AM) fungi interconnect plants in common mycorrhizal networks (CMNs) which can amplify competition among neighbors. Amplified competition might result from the fungi supplying mineral nutrients preferentially to hosts that abundantly provide fixed carbon, as suggested by research with organ-cultured roots. We examined whether CMNs supplied (15) N preferentially to large, nonshaded, whole plants. We conducted an intraspecific target-neighbor pot experiment with Andropogon gerardii and several AM fungi in intact, severed or prevented CMNs. Neighbors were supplied (15) N, and half of the target plants were shaded. Intact CMNs increased target dry weight (DW), intensified competition and increased size inequality. Shading decreased target weight, but shaded plants in intact CMNs had mycorrhizal colonization similar to that of sunlit plants. AM fungi in intact CMNs acquired (15) N from the substrate of neighbors and preferentially allocated it to sunlit, large, target plants. Sunlit, intact CMN, target plants acquired as much as 27% of their nitrogen from the vicinity of their neighbors, but shaded targets did not. These results suggest that AM fungi in CMNs preferentially provide mineral nutrients to those conspecific host individuals best able to provide them with fixed carbon or representing the strongest sinks, thereby potentially amplifying asymmetric competition below ground.

  8. Nutrient Allocation Strategies of Woody Plants: An Approach From the Scaling of Nitrogen and Phosphorus Between Twigs and Leaves

    Science.gov (United States)

    Yan, Z.; Li, P.; Chen, Y.; Han, W.; Fang, J.

    2015-12-01

    Allocation of limited nutrients, such as nitrogen (N) and phosphorus (P), among plant organs reflects the influences of evolutionary and ecological processes on functional traits of plants, and thus is related to functional groups and environmental conditions. In this study, we tested this hypothesis by exploring the stoichiometric scaling of N and P concentrations between twigs and leaves of 335 woody species from 12 forest sites across eastern China. There were significant scaling relationships between twig N (or P) and leaf N (or P) using reduced major axis (RMA) regression analysis; yet their scaling exponents varied among functional groups and changed with environmental factors. Evergreen broad-leaved plants had a higher exponent (αP) of twig P to leaf P than that of deciduous broad-leaved plants (1.26 vs. 0.96, p 1 at low latitude (23.2°N) to nutrient concentration increased, plants at low latitudes showed a faster increase in twig nutrient concentration, whereas plants at high latitudes presented a faster increase in leaf nutrient concentration. Such shifts in nutrient allocation strategy from low to high latitudes may be controlled by temperature. Overall, our findings provide a new approach to explore plant nutrient allocation strategies by analysing the stoichiometric scaling of nutrients among organs, which could broaden our understanding of the interactions between plants and their environments.

  9. Silicon alleviates drought stress of rice plants by improving plant water status, photosynthesis and mineral nutrient absorption.

    Science.gov (United States)

    Chen, Wei; Yao, Xiaoqin; Cai, Kunzheng; Chen, Jining

    2011-07-01

    Drought is a major constraint for rice production in the rainfed lowlands in China. Silicon (Si) has been verified to play an important role in enhancing plant resistance to environmental stress. Two near-isogenic lines of rice (Oryza sativa L.), w-14 (drought susceptible) and w-20 (drought resistant), were selected to study the effects of exogenous Si application on the physiological traits and nutritional status of rice under drought stress. In wet conditions, Si supply had no effects on growth and physiological parameters of rice plants. Drought stress was found to reduce dry weight, root traits, water potential, photosynthetic parameters, basal quantum yield (F(v)/F(0)), and maximum quantum efficiency of PSII photochemistry (F(v)/F(m)) in rice plants, while Si application significantly increased photosynthetic rate (Pr), transpiration rate (Tr), F(v)/F(0), and F(v)/F(m) of rice plants under drought stress. In addition, water stress increased K, Na, Ca, Mg, Fe content of rice plants, but Si treatment significantly reduced these nutrient level. These results suggested that silicon application was useful to increase drought resistance of rice through the enhancement of photochemical efficiency and adjustment of the mineral nutrient absorption in rice plants.

  10. Symptoms of nutritional deficiencies in neem plants cultivated in nutrient solution

    Directory of Open Access Journals (Sweden)

    Ronnky Chaell Braga da Silva

    2011-03-01

    Full Text Available The planting of forest species is an activity that, besides introducing new exotic types of plants, can lessen the environmental impacts resulting from extractivism. Nevertheless, such success depends, upon other factors, on the knowledge of the nutritional needs of the species to be used. This study intended to check the typical symptoms of nutritional deficiency of macronutrients in the culture of Neem, through the visual observation of the plants. The experiment was carried out in a greenhouse at the College of Agronomy and Veterinary Medicine (FAMEV of the Federal University of Mato Grosso (UFMT in Cuiabá/MT, and it was set up in randomized blocks, with seven treatments and three repetitions. Each experimental unit was represented by a plastic vase, two liters capacity. The treatments used were: complete nutritive solution and solution with the omission of the following nutrients: -N, -P, -K, -Ca, -Mg and -S. It was ascertained that the visual symptoms of nutrient deficiency were, as a general rule, of easy characterization except for the treatment with omission of sulphur. Therefore, the omission of macronutrients decreases the production of total dry matter of the Neem plants, except for the omission of the S nutrient.

  11. Growth, Development, and Mineral Nutrient Accumulation and Distribution in Tulip from Planting through Postanthesis Shoot Senescence

    Directory of Open Access Journals (Sweden)

    Carl E. Niedziela

    2015-01-01

    Full Text Available Tulips were grown under field conditions from mid-November through early-June. Plants were harvested and dissected into eight organs on twenty-one dates. These parts were dried, weighed, and analyzed for N, P, K, Ca, and Mg. A transition (as determined by curve join points from a linear to a steep negative cubic response occurred prior to shoot emergence for N (82 days after planting (DAP, at shoot emergence for K (93 DAP and Ca (94 DAP, and after shoot emergence for Mg (102 DAP and dry matter (118 DAP. A transition from a linear to a steeper linear response occurred at shoot emergence for P (93 DAP. Growth, organ development, and nutrient accumulation occurred continuously from planting to maturity (188 DAP, except for K which did not accumulate during the initial linear phase. Since the increase in accumulation of all five nutrients preceded the dry matter accumulation, these nutrients could be used as predictors in growth models. Practical implications from this study include the importance of maintaining soil Ca levels through liming and applying the N, P, and Mg as split applications with smaller rates at planting and larger rates at emergence. The entire K application may be applied at emergence.

  12. The Role of Strigolactones in Nutrient-Stress Responses in Plants

    Directory of Open Access Journals (Sweden)

    Marek Marzec

    2013-04-01

    Full Text Available Strigolactones (SLs are a new group of plant hormones, which have been intensively investigated during the last few years. The wide spectrum of SLs actions, including the regulation of shoot/root architecture, and the stimulation of the interactions between roots and fungi or bacteria, as well as the stimulation of germination of parasitic plants, indicates that this group of hormones may play an important role in the mechanisms that control soil exploration, and the root-mediated uptake of nutrients. Current studies have shown that SLs might be factors that have an influence on the plant response to a deficiency of macronutrients. Experimental data from the last four years have confirmed that the biosynthesis and exudation of SLs are increased under phosphorus and nitrogen deficiency. All these data suggest that SLs may regulate the complex response to nutrient stress, which include not only the modification of the plant developmental process, but also the cooperation with other organisms in order to minimize the effects of threats. In this paper the results of studies that indicate that SLs play an important role in the response to nutrient stress are reviewed and the consequences of the higher biosynthesis and exudation of SLs in response to phosphorus and nitrogen deficiency are discussed.

  13. Nutrient Release, Plant Nutrition, and Potassium Leaching from Polymer-Coated Fertilizer

    Directory of Open Access Journals (Sweden)

    Henrique Bley

    Full Text Available ABSTRACT The increase in food consumption and limitations in food production areas requires improved fertilizer efficiency. Slow- or controlled-release fertilizers are an alternative for synchronizing nutrient availability with the plant demands, reducing losses to the environment. The aim of this study was to evaluate the efficacy of polymer-coated KCl compared with conventional KCl. The products were incubated in soil under controlled conditions to evaluate the time required for nutrient release. A greenhouse experiment was performed with corn plants in pots with loamy sand- or clay-textured soil types to evaluate plant nutrition and losses due to leaching. The K application rates were 0, 18, 36, and 54 mg dm-3. The pots were irrigated, and the percolated liquid was collected. The plants were harvested 30 days after sowing to quantify dry matter (DM and its K content. In the incubation study, the K release from the coated fertilizer was found to be 42 % over 154 days. The data were fit to a linear function from which a period of 315 days was estimated as required for the release of 75 % of the nutrient. Meanwhile, conventional KCl releases 85 % of the K nutrient in the first 48h. In the cultivation of plants in pots, the coating reduced K losses due to leaching in the loamy sand soil; however, only the application rate of 54 mg dm-3 promoted DM production equivalent to conventional KCl. It is possible that the need for K in the early stages of corn development was not met by a coated KCl.

  14. Plant allocation of carbon to defense as a function of herbivory, light and nutrient availability

    Science.gov (United States)

    DeAngelis, Donald L.; Ju, Shu; Liu, Rongsong; Bryant, John P.; Gourley, Stephen A.

    2012-01-01

    We use modeling to determine the optimal relative plant carbon allocations between foliage, fine roots, anti-herbivore defense, and reproduction to maximize reproductive output. The model treats these plant components and the herbivore compartment as variables. Herbivory is assumed to be purely folivory. Key external factors include nutrient availability, degree of shading, and intensity of herbivory. Three alternative functional responses are used for herbivory, two of which are variations on donor-dependent herbivore (models 1a and 1b) and one of which is a Lotka–Volterra type of interaction (model 2). All three were modified to include the negative effect of chemical defenses on the herbivore. Analysis showed that, for all three models, two stable equilibria could occur, which differs from most common functional responses when no plant defense component is included. Optimal strategies of carbon allocation were defined as the maximum biomass of reproductive propagules produced per unit time, and found to vary with changes in external factors. Increased intensity of herbivory always led to an increase in the fractional allocation of carbon to defense. Decreases in available limiting nutrient generally led to increasing importance of defense. Decreases in available light had little effect on defense but led to increased allocation to foliage. Decreases in limiting nutrient and available light led to decreases in allocation to reproduction in models 1a and 1b but not model 2. Increases in allocation to plant defense were usually accompanied by shifts in carbon allocation away from fine roots, possibly because higher plant defense reduced the loss of nutrients to herbivory.

  15. Effect of Fenton pre-oxidation on mobilization of nutrients and efficient subsequent bioremediation of crude oil-contaminated soil.

    Science.gov (United States)

    Xu, Jinlan; Kong, Fanxing; Song, Shaohua; Cao, Qianqian; Huang, Tinglin; Cui, Yiwei

    2017-08-01

    Fenton pre-oxidation and a subsequent bioremediation phase of 80 days were used to investigate the importance of matching concentration of residual indigenous bacteria and nutrient levels on subsequent bioremediation of crude oil. Experiments were performed using either high (>10(7.7 ± 0.2) CFU/g soil) or low (soil) concentrations of bacteria and three different nutrient levels: enough (C/N > 9.8), moderate (C/N:5-9.8), and lacking nutrient level (C/N nutrient level and the population of residual indigenous bacteria. Up to 53% of total petroleum hydrocarbon (TPH) and 58% of main hydrocarbon (C15C25, during the first 10 days) were removed from the soil. Under matching conditions, the activity of indigenous bacteria and nutrient mobilization were enhanced, promoting the bioremediation of crude oil. In addition, the biodegradation of long chain molecules (C26C30) required a high level of NH4(+)-N. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Nutrient accumulation at the initial growth of pitaya plants according to phosphorus fertilization

    Directory of Open Access Journals (Sweden)

    Rodrigo Amato Moreira

    2016-09-01

    Full Text Available The knowledge about the amount of nutrient uptake in pitaya plants helps the balanced fertilizer recommendation for the crop, providing adequate nutrition and contributing to the maximum expression of this species potential. This research was carried out in order to evaluate the growth, nutrient accumulation and efficiency of absorption, transportation and use of P by pitaya according to phosphorus fertilization. A randomized blocks design was used, with five doses of P (0 mg dm-3, 20 mg dm-3, 40 mg dm-3, 80 mg dm-3 and 160 mg dm-3 incorporated into the soil, with four replications, three pots per plot and one cutting per pot. Differences in the nutrient accumulation of all doses were evident in the pitaya shoots and roots, as well as in the efficiency of absorption, transport and use of P, according to phosphorus fertilization. The nutrient accumulation in the pitaya roots was ranked in the following order: N > K > Ca > S > P > Mg > Fe > Mn > Zn > B ≥ Cu. For the shoots, the order was: K > N > Ca > S > Mg > P > Mn > Fe > Zn > B ≥ Cu. The initial growth of pitaya plants was maximum with 81 mg dm-3 of P, in a Red-Yellow Dystrophic Latosol. The application of 44-67 mg dm3 of P to the soil promoted the highest accumulation of macro and micronutrients in the pitaya.

  17. Plant growth-promoting rhizobacteria affect the growth and nutrient uptake of Fraxinus americana container seedlings.

    Science.gov (United States)

    Liu, Fangchun; Xing, Shangjun; Ma, Hailin; Du, Zhenyu; Ma, Bingyao

    2013-05-01

    Plant growth-promoting rhizobacteria (PGPR) are important catalysts that regulate the functional properties of agricultural systems. However, there is little information on the effect of PGPR inoculation on the growth and nutrient accumulation of forest container seedlings. This study determined the effects of a growth medium inoculated with PGPR on the nutrient uptake, nutrient accumulation, and growth of Fraxinus americana container seedlings. PGPR inoculation with fertilizer increased the dry matter accumulation of the F. americana aerial parts with delayed seedling emergence time. Under fertilized conditions, the accumulation time of phosphorous (P) and potassium (K) in the F. americana aerial parts was 13 days longer due to PGPR inoculation. PGPR increased the maximum daily P and K accumulations in fertilized seedlings by 9.31 and 10.44 %, respectively, but had little impact on unfertilized ones. Regardless of fertilizer application, the root exudates, namely sugars, amino acids, and organic acids significantly increased because of PGPR inoculation. PGPR inoculation with fertilizer increased the root, shoot, and leaf yields by 19.65, 22.94, and 19.44 %, respectively, as well as the P and K contents by 8.33 and 10.60 %, respectively. Consequently, the N, P, and K uptakes increased by 19.85, 31.97, and 33.95 %, respectively. Hence, PGPR inoculation with fertilizer can be used as a bioenhancer for plant growth and nutrient uptake in forest container seedling nurseries.

  18. The effect of intra- and interregional labour mobility on plant performance in Denmark

    DEFF Research Database (Denmark)

    Timmermans, Bram; Boschma, Ron

    2014-01-01

    This article investigates the impact of labour mobility on plant performance in Denmark. Our study shows that the effect of labour mobility can only be assessed when one accounts for the type of skills that flow into the plant and the degree to which these match the existing skills at the plant l...

  19. The R* rule and energy flux in a plant-nutrient ecosystem.

    Science.gov (United States)

    Ju, Shu; DeAngelis, Donald L

    2009-02-07

    The R* rule predicts that the species that can survive in steady state at the lowest level of limiting resource, R*, excludes all other species. Simple models indicate that this concept is not necessarily consistent with Lotka's conjecture that an ecological system should evolve towards a state of maximum power, Max(G), where G is the power, or rate of biomass production of the system. To explore the relationship in detail, we used a published model of a plant-nutrient system in which a plant can use various strategies, S, of allocation of energy between foliage, roots, and wood. We found that the allocation strategy, S(MinR*), that leads to Min(N(pore*), where N(pore*) is a limiting nutrient in soil pore water in our model (and equivalent to R* in Tilman's notation), is the same as the strategy, S(MaxG_root), for which energy flux to roots is maximized. However, that allocation strategy is different from the strategy, S(MaxG), that produces maximum power, or maximum photosynthetic rate, for the plant system, Max(G). Hence, we conclude that Min(N(pore*) and Max(G) should not necessarily co-occur in an ecological system. We also examined which strategy, S(fit), was fittest; that is, eliminated any other strategies, when allowed to compete. The strategy S(fit) differed from S(MinR*, S(MaxG), and S(MaxG_root), which we demonstrated mathematically. We also considered the feasible situation in which a plant is able to positively influence external nutrient input to the system. Under such conditions, the strategy, S(MaxG_root), that maximizes energy flux to roots was the same as the strategy, S(MaxR*, that leads to maximum concentration of available nutrient in soil pore water, Max(N pore*), and not same as S(MinR*, for Min(N pore*).

  20. Reciprocal effects of litter from exotic and congeneric native plant species via soil nutrients.

    Directory of Open Access Journals (Sweden)

    Annelein Meisner

    Full Text Available Invasive exotic plant species are often expected to benefit exclusively from legacy effects of their litter inputs on soil processes and nutrient availability. However, there are relatively few experimental tests determining how litter of exotic plants affects their own growth conditions compared to congeneric native plant species. Here, we test how the legacy of litter from three exotic plant species affects their own performance in comparison to their congeneric natives that co-occur in the invaded habitat. We also analyzed litter effects on soil processes. In all three comparisons, soil with litter from exotic plant species had the highest respiration rates. In two out of the three exotic-native species comparisons, soil with litter from exotic plant species had higher inorganic nitrogen concentrations than their native congener, which was likely due to higher initial litter quality of the exotics. When litter from an exotic plant species had a positive effect on itself, it also had a positive effect on its native congener. We conclude that exotic plant species develop a legacy effect in soil from the invaded range through their litter inputs. This litter legacy effect results in altered soil processes that can promote both the exotic plant species and their native congener.

  1. Nutrient allocation strategies of woody plants: an approach from the scaling of nitrogen and phosphorus between twig stems and leaves.

    Science.gov (United States)

    Yan, Zhengbing; Li, Peng; Chen, Yahan; Han, Wenxuan; Fang, Jingyun

    2016-02-05

    Allocation of limited nutrients, such as nitrogen (N) and phosphorus (P), among plant organs reflects the influences of evolutionary and ecological processes on functional traits of plants, and thus is related to functional groups and environmental conditions. In this study, we tested this hypothesis by exploring the stoichiometric scaling of N and P concentrations between twig stems and leaves of 335 woody species from 12 forest sites across eastern China. Scaling exponents of twig stem N (or P) to leaf N (or P) varied among functional groups. With increasing latitude, these scaling exponents significantly decreased from >1 at low latitude to nutrient concentration increased, plants at low latitudes showed a faster increase in twig stem nutrient concentration, whereas plants at high latitudes presented a faster increase in leaf nutrient concentration. Such shifts in nutrient allocation strategy from low to high latitudes may be controlled by temperature. Overall, our findings provide a new approach to explore plant nutrient allocation strategies by analysing the stoichiometric scaling of nutrients among organs, which could broaden our understanding of the interactions between plants and their environments.

  2. PHOTOSYNTHESIS AND ABSORPTION OF MINERAL NUTRIENT IN TOMATO PLANTS UNDER VARIOUS ROOT ZONE TEMPERATURE AND LIGHT CONDITIONS

    OpenAIRE

    Kosobrukhov, A. A.; Bagnavets, E. A.; Semenova, N. A.

    1988-01-01

    Effect of various light and temperature regimes in the root zone on the light stage of photosynthesis, gas exchange, growth processes and absorption of mineral nutrients by tomato plants were studied. Optimum temperatures for dry matter accumulation and absorption of mineral nutrients were found to be shifted when the irradiation condition were changed. A shift of optimum temperatures for dry matter accumulation and absorption of mineral nutrients was found to be due to a change in irradiatio...

  3. Automated pH Control of Nutrient Solution in a Hydroponic Plant Growth System

    Science.gov (United States)

    Smith, B.; Dogan, N.; Aglan, H.; Mortley, D.; Loretan, P.

    1998-01-01

    Over, the years, NASA has played an important role in providing to and the development of automated nutrient delivery and monitoring, systems for growing crops hydroponically for long term space missions. One example are the systems used in the Biomass Production Chamber (BPC) at Kennedy Space Center (KSC). The current KSC monitoring system is based on an engineering workstation using standard analog/digital input/output hardware and custom written software. The monitoring system uses completely separate sensors to provide a check of control sensor accuracy and has the ability to graphically display and store data form past experiment so that they are available for data analysis [Fortson, 1992]. In many cases, growing systems have not been fitted with the kind of automated control systems as used at KSC. The Center for Food and Environmental Systems for Human Exploration of Space (CFESH) located on the campus of Tuskegee University, has effectively grown sweetpotatoes and peanuts hydroponically for the past five years. However they have adjusted the pH electrical conductivity and volume of the hydroponic nutrient solution only manually at times when the solution was to be replenished or changed out according to its protocol (e.g. one-week, two-week, or two-day cycle). But the pH of the nutrient solution flowing through the channel is neither known nor controlled between the update, change out, or replenishment period. Thus, the pH of the nutrient solution is not held at an optimum level over the span of the plant's growth cycle. To solve this dilemma, an automated system for the control and data logging of pH data relative to sweetpotato production using the nutrient film technique (NFT) has been developed, This paper discusses a microprocessor-based system, which was designed to monitor, control, and record the pH of a nutrient solution used for growing sweetpotatoes using NFT.

  4. Nutrient limitation of native and invasive N2-fixing plants in northwest prairies

    Science.gov (United States)

    Thorpe, Andrea S.; Perakis, Steven S.; Catricala, Christina; Kaye, Thomas N.

    2013-01-01

    Nutrient rich conditions often promote plant invasions, yet additions of non-nitrogen (N) nutrients may provide a novel approach for conserving native symbiotic N-fixing plants in otherwise N-limited ecosystems. Lupinus oreganus is a threatened N-fixing plant endemic to prairies in western Oregon and southwest Washington (USA). We tested the effect of non-N fertilizers on the growth, reproduction, tissue N content, and stable isotope δ15N composition of Lupinus at three sites that differed in soil phosphorus (P) and N availability. We also examined changes in other Fabaceae (primarily Vicia sativa and V. hirsuta) and cover of all plant species. Variation in background soil P and N availability shaped patterns of nutrient limitation across sites. Where soil P and N were low, P additions increased Lupinus tissue N and altered foliar δ15N, suggesting P limitation of N fixation. Where soil P was low but N was high, P addition stimulated growth and reproduction in Lupinus. At a third site, with higher soil P, only micro- and macronutrient fertilization without N and P increased Lupinus growth and tissue N. Lupinus foliar δ15N averaged −0.010‰ across all treatments and varied little with tissue N, suggesting consistent use of fixed N. In contrast, foliar δ15N of Vicia spp. shifted towards 0‰ as tissue N increased, suggesting that conditions fostering N fixation may benefit these exotic species. Fertilization increased cover, N fixation, and tissue N of non-target, exotic Fabaceae, but overall plant community structure shifted at only one site, and only after the dominant Lupinus was excluded from analyses. Our finding that non-N fertilization increased the performance of Lupinus with few community effects suggests a potential strategy to aid populations of threatened legume species. The increase in exotic Fabaceae species that occurred with fertilization further suggests that monitoring and adaptive management should accompany any large scale applications.

  5. Nutrient limitation of native and invasive N2-fixing plants in northwest prairies.

    Directory of Open Access Journals (Sweden)

    Andrea S Thorpe

    Full Text Available Nutrient rich conditions often promote plant invasions, yet additions of non-nitrogen (N nutrients may provide a novel approach for conserving native symbiotic N-fixing plants in otherwise N-limited ecosystems. Lupinus oreganus is a threatened N-fixing plant endemic to prairies in western Oregon and southwest Washington (USA. We tested the effect of non-N fertilizers on the growth, reproduction, tissue N content, and stable isotope δ(15N composition of Lupinus at three sites that differed in soil phosphorus (P and N availability. We also examined changes in other Fabaceae (primarily Vicia sativa and V. hirsuta and cover of all plant species. Variation in background soil P and N availability shaped patterns of nutrient limitation across sites. Where soil P and N were low, P additions increased Lupinus tissue N and altered foliar δ(15N, suggesting P limitation of N fixation. Where soil P was low but N was high, P addition stimulated growth and reproduction in Lupinus. At a third site, with higher soil P, only micro- and macronutrient fertilization without N and P increased Lupinus growth and tissue N. Lupinus foliar δ(15N averaged -0.010‰ across all treatments and varied little with tissue N, suggesting consistent use of fixed N. In contrast, foliar δ(15N of Vicia spp. shifted towards 0‰ as tissue N increased, suggesting that conditions fostering N fixation may benefit these exotic species. Fertilization increased cover, N fixation, and tissue N of non-target, exotic Fabaceae, but overall plant community structure shifted at only one site, and only after the dominant Lupinus was excluded from analyses. Our finding that non-N fertilization increased the performance of Lupinus with few community effects suggests a potential strategy to aid populations of threatened legume species. The increase in exotic Fabaceae species that occurred with fertilization further suggests that monitoring and adaptive management should accompany any large scale

  6. Nutrient limitation of native and invasive N2-fixing plants in northwest prairies.

    Science.gov (United States)

    Thorpe, Andrea S; Perakis, Steven; Catricala, Christina; Kaye, Thomas N

    2013-01-01

    Nutrient rich conditions often promote plant invasions, yet additions of non-nitrogen (N) nutrients may provide a novel approach for conserving native symbiotic N-fixing plants in otherwise N-limited ecosystems. Lupinus oreganus is a threatened N-fixing plant endemic to prairies in western Oregon and southwest Washington (USA). We tested the effect of non-N fertilizers on the growth, reproduction, tissue N content, and stable isotope δ(15)N composition of Lupinus at three sites that differed in soil phosphorus (P) and N availability. We also examined changes in other Fabaceae (primarily Vicia sativa and V. hirsuta) and cover of all plant species. Variation in background soil P and N availability shaped patterns of nutrient limitation across sites. Where soil P and N were low, P additions increased Lupinus tissue N and altered foliar δ(15)N, suggesting P limitation of N fixation. Where soil P was low but N was high, P addition stimulated growth and reproduction in Lupinus. At a third site, with higher soil P, only micro- and macronutrient fertilization without N and P increased Lupinus growth and tissue N. Lupinus foliar δ(15)N averaged -0.010‰ across all treatments and varied little with tissue N, suggesting consistent use of fixed N. In contrast, foliar δ(15)N of Vicia spp. shifted towards 0‰ as tissue N increased, suggesting that conditions fostering N fixation may benefit these exotic species. Fertilization increased cover, N fixation, and tissue N of non-target, exotic Fabaceae, but overall plant community structure shifted at only one site, and only after the dominant Lupinus was excluded from analyses. Our finding that non-N fertilization increased the performance of Lupinus with few community effects suggests a potential strategy to aid populations of threatened legume species. The increase in exotic Fabaceae species that occurred with fertilization further suggests that monitoring and adaptive management should accompany any large scale applications.

  7. Plant Growth Environments with Programmable Relative Humidity and Homogeneous Nutrient Availability.

    Directory of Open Access Journals (Sweden)

    Kara R Lind

    Full Text Available We describe the design, characterization, and use of "programmable", sterile growth environments for individual (or small sets of plants. The specific relative humidities and nutrient availability experienced by the plant is established (RH between 15% and 95%; nutrient concentration as desired during the setup of the growth environment, which takes about 5 minutes and <1$ in disposable cost. These systems maintain these environmental parameters constant for at least 14 days with minimal intervention (one minute every two days. The design is composed entirely of off-the-shelf components (e.g., LEGO® bricks and is characterized by (i a separation of root and shoot environment (which is physiologically relevant and facilitates imposing specific conditions on the root system, e.g., darkness, (ii the development of the root system on a flat surface, where the root enjoys constant contact with nutrient solution and air, (iii a compatibility with root phenotyping. We demonstrate phenotyping by characterizing root systems of Brassica rapa plants growing in different relative humidities (55%, 75%, and 95%. While most phenotypes were found to be sensitive to these environmental changes, a phenotype tightly associated with root system topology-the size distribution of the areas encircled by roots-appeared to be remarkably and counterintuitively insensitive to humidity changes. These setups combine many of the advantages of hydroponics conditions (e.g., root phenotyping, complete control over nutrient composition, scalability and soil conditions (e.g., aeration of roots, shading of roots, while being comparable in cost and setup time to Magenta® boxes.

  8. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale. PMID:27149113

  9. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Directory of Open Access Journals (Sweden)

    Adrian Zwolicki

    Full Text Available We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina. Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  10. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  11. Nutrient removal through autumn harvest of Phragmites australis and Thypha latifolia shoots in relation to nutrient loading in a wetland system used for polishing sewage treatment plant effluent.

    Science.gov (United States)

    Toet, Sylvia; Bouwman, Meike; Cevaal, Annechien; Verhoeven, Jos T A

    2005-01-01

    The efficacy and feasibility of annual harvesting of Phragmites australis and Typha latifolia shoots in autumn for nutrient removal was evaluated in a wetland system used for polishing sewage treatment plant (STP) effluent. Aboveground biomass and nutrient dynamics nutrient removal through harvest were studied in parallel ditches with stands of Phragmites or Typha that were mown in October during two successive years. The inflow rate of STP effluent to the ditches was experimentally varied, resulting in pairs of ditches with mean hydraulic retention times (HRT) of 0.3, 0.8, 2.3, and 9.3 days, corresponding to N and P mass loading rates of 122-4190 g N m(-2) yr(-1) and 28.3-994 g P m(-2) yr(-1). Nitrogen and P removal efficiency by harvest of Phragmites and Typha shoots in October increased with increasing HRT, despite the opposite HRT effect on N and P standing stocks. This removal through harvest appeared to be useful in treatment wetlands with N and P mass loading rates lower than approximately 120 g N m(-2) yr(-1) and 30 g P m(-2) yr(-1), corresponding to a HRT of roughly 9 days in the ditches of this wetland system. At the HRT of 9.3 days, the annual mass input to the ditches was reduced through the harvest by 7.0-11% and 4.5 -9.2% for N and P, respectively. At the higher nutrient mass loading rates, the nutrient removal through harvest was insignificant compared to the mass inputs. The vitality of Phragmites and Typha, measured as maximum aboveground biomass, was not affected by the annual cutting of the shoots in autumn over two years. The Typha stands yielded higher N and P removal efficiencies through shoot harvest than the Phragmites stands, which was largely the result of lower decreases in N and P standing stocks between August and October. This difference in nutrient standing stocks between the two species was caused by a combined effect of greater decreases in nutrient concentrations largely due to higher nutrient retranslocation efficiencies of

  12. Impact of hydrochar application on soil nutrient dynamics and plant availability

    Science.gov (United States)

    Bargmann, I.; Greef, J. M.; Kücke, M.

    2012-04-01

    In order to investigate potentials for the use of HTC-products (hydrochar) in agriculture, the influence of soil application of different hydrochars on soil nutrient dynamics as well as on plant growth and plant nutrient uptake was determined. Hydrochars were produced from sugar beet pulps and brewer's grains by carbonization at 190°C for 4 respectively 12 hours each. Incubation experiments with two soil types showed an increase of soil pH by 0.5 to 2.5 pH units, depending on the amount of hydrochar added and the process conditions (i.e. addition of calcium carbonate during production). The application of HTC to soil decreased the plant available nitrogen to almost zero in the first week after HTC-addition, followed by a slow re-release of nitrate in the following weeks. A similar immobilization of soluble phosphate was observed for one soil type, although to a lower extent. The plant availability of phosphorus in hydrochars and biochars is subject of current trials. Furthermore it is actually investigated to what extend the N immobilization is related to soil microbial activity. Germination tests with barley showed toxic effects of hydrochar application on germination, both by direct contact of grains with HTC as well as by release of gaseous compounds from HTC. Effects differ significantly for different parent materials and pretreatments (washing, drying, storage). The influence of HTC-addition to soil on plant growth and nutrient uptake was investigated in pot experiments with various crop species (barley, phaseolus bean, leek), comparing HTC from different parent materials and process parameters such as carbonization time. With increasing addition of HTC, the N availability was decreased and N contents in the plant were significantly lower compared with the untreated control. The plant growth response was different for each tested crop. On barley, leaf tip necroses were observed, but not on phaseolus. Biomass yield of barley and beans was generally increased

  13. Influence of nutrient composition and plant growth regulators on callus induction and plant regeneration in glutinous rice (Oryza sativa L.).

    Science.gov (United States)

    Duangsee, K; Bunnag, S

    2014-01-01

    The potential for callus induction and regeneration depends on nutrient composition and plant growth regulators. The aim of the present study was to investigate the effect of nutrient composition and plant growth regulators on callus induction and plant regeneration in the glutinous rice cultivar Khunvang. The effect of 2,4-D concentrations (1, 2, 3, 4 and 5 mg L(-1)) on callus induction and growth were investigated. The results revealed that the highest percentage of callus induction (97%) was observed in MS medium supplemented with 5 mg L(-1) 2,4-D under 16 h Photoperiod. The effects of casein hydrolysate concentrations of casein hydrolysate (0, 300, 500, 700 and 900 mg L(-1)) and proline (0, 300, 500, 700 and 900 mg L(-1)) on callus induction and growth of Khunvang were also observed. The results indicated that the increasing casein hydrolysate and proline concentrations did not show a significant effect on callus growth. However, proline concentration of 900 mg L(-1) yielded 85.67% of callus growth.

  14. The node, a hub for mineral nutrient distribution in graminaceous plants.

    Science.gov (United States)

    Yamaji, Naoki; Ma, Jian Feng

    2014-09-01

    Mineral elements, including both essential and toxic elements, are delivered to different tissues after they are taken up from the roots, but the mechanism (or mechanisms) underlying the distribution remains poorly understood. In graminaceous plants, this distribution occurs in nodes, which have a complex, well-organized vascular system. A transfer of mineral elements between different vascular bundles is required, especially for preferential distribution to developing tissues that have low transpiration but high nutrient requirements. This intervascular transfer is mediated by various transporters localized at different cells in the node. In this opinion article, we propose four modes of distribution for different mineral elements: xylem-switch, phloem-tropic, phloem-kickback, and minimum-shift, based on specific molecular transport processes identified in the nodes mainly of rice (Oryza sativa). We also discuss the prospects for future studies on mineral nutrient distribution in the nodes.

  15. A novel type of nutritional ant-plant interaction: ant partners of carnivorous pitcher plants prevent nutrient export by dipteran pitcher infauna

    National Research Council Canada - National Science Library

    Scharmann, Mathias; Thornham, Daniel G; Grafe, T Ulmar; Federle, Walter

    2013-01-01

    .... It has recently been suggested that this ant-plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N...

  16. A Novel Type of Nutritional Ant-Plant Interaction: Ant Partners of Carnivorous Pitcher Plants Prevent Nutrient Export by Dipteran Pitcher Infauna. e63556

    National Research Council Canada - National Science Library

    Scharmann, Mathias; Thornham, Daniel G; Grafe, T Ulmar; Federle, Walter

    2013-01-01

    .... It has recently been suggested that this ant-plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N...

  17. PlaMoM: a comprehensive database compiles plant mobile macromolecules

    Science.gov (United States)

    Guan, Daogang; Yan, Bin; Thieme, Christoph; Hua, Jingmin; Zhu, Hailong; Boheler, Kenneth R.; Zhao, Zhongying; Kragler, Friedrich; Xia, Yiji; Zhang, Shoudong

    2017-01-01

    In plants, various phloem-mobile macromolecules including noncoding RNAs, mRNAs and proteins are suggested to act as important long-distance signals in regulating crucial physiological and morphological transition processes such as flowering, plant growth and stress responses. Given recent advances in high-throughput sequencing technologies, numerous mobile macromolecules have been identified in diverse plant species from different plant families. However, most of the identified mobile macromolecules are not annotated in current versions of species-specific databases and are only available as non-searchable datasheets. To facilitate study of the mobile signaling macromolecules, we compiled the PlaMoM (Plant Mobile Macromolecules) database, a resource that provides convenient and interactive search tools allowing users to retrieve, to analyze and also to predict mobile RNAs/proteins. Each entry in the PlaMoM contains detailed information such as nucleotide/amino acid sequences, ortholog partners, related experiments, gene functions and literature. For the model plant Arabidopsis thaliana, protein–protein interactions of mobile transcripts are presented as interactive molecular networks. Furthermore, PlaMoM provides a built-in tool to identify potential RNA mobility signals such as tRNA-like structures. The current version of PlaMoM compiles a total of 17 991 mobile macromolecules from 14 plant species/ecotypes from published data and literature. PlaMoM is available at http://www.systembioinfo.org/plamom/. PMID:27924044

  18. Nutrient status and plant growth effects of forest soils in the Basin of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Fenn, M.E. [USDA Forest Service, Pacific Southwest Research Station, Forest Fire Laboratory, 4955 Canyon Crest Dr., Riverside, CA 92507 (United States)]. E-mail: mfenn@fs.fed.us; Perea-Estrada, V.M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico); Bauer, L.I. de [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico)]. E-mail: libauer@colpos.mx; Perez-Suarez, M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico); Parker, D.R. [Department of Environmental Sciences, University of California, Riverside, CA 92521 (United States)]. E-mail: david.parker@ucr.edu; Cetina-Alcala, V.M. [Instituto de Recursos Naturales, Colegio de Postgraduados, CP 56230 Montecillo (Mexico)

    2006-03-15

    The nutrient status of forest soils in the Mexico City Air Basin was evaluated by observing plant growth responses to fertilization with N, P or both nutrients combined. P deficiency was the most frequent condition for soil from two high pollution sites and N deficiency was greatest at a low N deposition site. Concentrations of Pb and Ni, and to a lesser extent Zn and Co, were higher at the high pollution sites. However, positive plant growth responses to P and sometimes to N, and results of wheat root elongation bioassays, suggest that heavy metal concentrations were not directly phytotoxic. Further studies are needed to determine if heavy metal toxicity to mycorrhizal symbionts of eucalyptus (Eucalyptus camaldulensis Dehnh.) from high pollution sites may explain the P deficiency and stunted growth. P deficiency is expected to limit the capacity for biotic N retention in N saturated forested watersheds in the Basin of Mexico dominated by Andisols. - Plant response to N deposition may be limited by P limitation in forests growing on Andisol soils in the Basin of Mexico.

  19. Allometry and development in herbaceous plants: functional responses of meristem allocation to light and nutrient availability.

    Science.gov (United States)

    Bonser, Stephen P; Aarssen, Lonnie W

    2003-03-01

    We examined the relationship between meristem allocation and plant size for four annual plant species: Arabidopsis thaliana, Arenaria serphyllifolia, Brassica rapa, and Chaenorrhinum minus. Gradients of light and nutrient availability were used to obtain a range of plant sizes for each of these species. Relative allocation to reproductive, inactive, and growth meristems were used to measure reproductive effort, apical dominance, and branching intensity, respectively. We measured allocation to each of these three meristem fates at weekly intervals throughout development and at final developmental stage. At all developmental stages reproductive effort and branching intensity tended to increase with increasing plant size (i.e., due to increasing resource availability) and apical dominance tended to decrease with increasing plant size. We interpret these responses as a strategy for plants to maximize fitness across a range of environments. In addition, significant differences in meristem response among species may be important in defining the range of habitats in which a species can exist and may help explain patterns of species competition and coexistence in habitats with variable resource availability.

  20. Labour Mobility and Plant Performance in Denmark: The Significance of Related Inflows

    DEFF Research Database (Denmark)

    Timmermans, Bram; Boschma, Ron

    This paper investigates the impact of different types of labour mobility on plant performance, making use of the IDA-database that provides detailed information on all individuals and plants for the whole of Denmark. Our study shows that the effect of labour mobility can only be assessed when one a...

  1. Effect of arbuscular mycorrhizal colonization and two levels of compost supply on nutrient uptake and flowering of pelargonium plants.

    Science.gov (United States)

    Perner, Henrike; Schwarz, Dietmar; Bruns, Christian; Mäder, Paul; George, Eckhard

    2007-07-01

    Two challenges frequently encountered in the production of ornamental plants in organic horticulture are: (1) the rate of mineralization of phosphorus (P) and nitrogen (N) from organic fertilizers can be too slow to meet the high nutrient demand of young plants, and (2) the exclusive use of peat as a substrate for pot-based plant culture is discouraged in organic production systems. In this situation, the use of beneficial soil microorganisms in combination with high quality compost substrates can contribute to adequate plant growth and flower development. In this study, we examined possible alternatives to highly soluble fertilizers and pure peat substrates using pelargonium (Pelargonium peltatum L'Her.) as a test plant. Plants were grown on a peat-based substrate with two rates of compost addition and with and without arbuscular mycorrhizal (AM) fungi. Inoculation with three different commercial AM inocula resulted in colonization rates of up to 36% of the total root length, whereas non-inoculated plants remained free of root colonization. Increasing the rate of compost addition increased shoot dry weight and shoot nutrient concentrations, but the supply of compost did not always completely meet plant nutrient demand. Mycorrhizal colonization increased the number of buds and flowers, as well as shoot P and potassium (K) concentrations, but did not significantly affect shoot dry matter or shoot N concentration. We conclude that addition of compost in combination with mycorrhizal inoculation can improve nutrient status and flower development of plants grown on peat-based substrates.

  2. A mathematical model for investigating the effect of cluster roots on plant nutrient uptake

    KAUST Repository

    Zygalakis, K. C.

    2012-04-01

    Cluster roots are thought to play an important role in mediating nutrient uptake by plants. In this paper we develop a mathematical model for the transport and uptake of phosphate by a single root. Phosphate is assumed to diffuse in the soil fluid phase and can also solubilised due to citrate exudation. Using multiple scale homogenisation techniques we derive an effective model that accounts for the cumulative effect of citrate exudation and phosphate uptake by cluster roots whilst still retaining all the necessary information about the microscale geometry and effects. © 2012 EDP Sciences and Springer.

  3. A mathematical model for investigating the effect of cluster roots on plant nutrient uptake

    Science.gov (United States)

    Zygalakis, K. C.; Roose, T.

    2012-04-01

    Cluster roots are thought to play an important role in mediating nutrient uptake by plants. In this paper we develop a mathematical model for the transport and uptake of phosphate by a single root. Phosphate is assumed to diffuse in the soil fluid phase and can also solubilised due to citrate exudation. Using multiple scale homogenisation techniques we derive an effective model that accounts for the cumulative effect of citrate exudation and phosphate uptake by cluster roots whilst still retaining all the necessary information about the microscale geometry and effects.

  4. A novel type of nutritional ant-plant interaction: ant partners of carnivorous pitcher plants prevent nutrient export by dipteran pitcher infauna.

    Directory of Open Access Journals (Sweden)

    Mathias Scharmann

    Full Text Available Many plants combat herbivore and pathogen attack indirectly by attracting predators of their herbivores. Here we describe a novel type of insect-plant interaction where a carnivorous plant uses such an indirect defence to prevent nutrient loss to kleptoparasites. The ant Camponotus schmitzi is an obligate inhabitant of the carnivorous pitcher plant Nepenthes bicalcarata in Borneo. It has recently been suggested that this ant-plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N. bicalcarata host plant leaves naturally have an elevated (15N/(14N stable isotope abundance ratio (δ(15N when colonised by C. schmitzi. This indicates that a higher proportion of the plants' nitrogen is insect-derived when C. schmitzi ants are present (ca. 100%, vs. 77% in uncolonised plants and that more nitrogen is available to them. We demonstrated direct flux of nutrients from the ants to the host plant in a (15N pulse-chase experiment. As C. schmitzi ants only feed on nectar and pitcher contents of their host, the elevated foliar δ(15N cannot be explained by classic ant-feeding (myrmecotrophy but must originate from a higher efficiency of the pitcher traps. We discovered that C. schmitzi ants not only increase the pitchers' capture efficiency by keeping the pitchers' trapping surfaces clean, but they also reduce nutrient loss from the pitchers by predating dipteran pitcher inhabitants (infauna. Consequently, nutrients the pitchers would have otherwise lost via emerging flies become available as ant colony waste. The plants' prey is therefore conserved by the ants. The interaction between C. schmitzi, N. bicalcarata and dipteran pitcher infauna represents a new type of mutualism where animals mitigate the damage by nutrient thieves to a plant.

  5. A novel type of nutritional ant-plant interaction: ant partners of carnivorous pitcher plants prevent nutrient export by dipteran pitcher infauna.

    Science.gov (United States)

    Scharmann, Mathias; Thornham, Daniel G; Grafe, T Ulmar; Federle, Walter

    2013-01-01

    Many plants combat herbivore and pathogen attack indirectly by attracting predators of their herbivores. Here we describe a novel type of insect-plant interaction where a carnivorous plant uses such an indirect defence to prevent nutrient loss to kleptoparasites. The ant Camponotus schmitzi is an obligate inhabitant of the carnivorous pitcher plant Nepenthes bicalcarata in Borneo. It has recently been suggested that this ant-plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N. bicalcarata host plant leaves naturally have an elevated (15)N/(14)N stable isotope abundance ratio (δ(15)N) when colonised by C. schmitzi. This indicates that a higher proportion of the plants' nitrogen is insect-derived when C. schmitzi ants are present (ca. 100%, vs. 77% in uncolonised plants) and that more nitrogen is available to them. We demonstrated direct flux of nutrients from the ants to the host plant in a (15)N pulse-chase experiment. As C. schmitzi ants only feed on nectar and pitcher contents of their host, the elevated foliar δ(15)N cannot be explained by classic ant-feeding (myrmecotrophy) but must originate from a higher efficiency of the pitcher traps. We discovered that C. schmitzi ants not only increase the pitchers' capture efficiency by keeping the pitchers' trapping surfaces clean, but they also reduce nutrient loss from the pitchers by predating dipteran pitcher inhabitants (infauna). Consequently, nutrients the pitchers would have otherwise lost via emerging flies become available as ant colony waste. The plants' prey is therefore conserved by the ants. The interaction between C. schmitzi, N. bicalcarata and dipteran pitcher infauna represents a new type of mutualism where animals mitigate the damage by nutrient thieves to a plant.

  6. Plant‐O‐Matic: a dynamic and mobile guide to all plants of the Americas

    DEFF Research Database (Denmark)

    Goldsmith, Greogory R.; Holme, Naia Morueta; Sandel, Brody Steven

    2016-01-01

    000 plant species. Plant-O-Matic, a free iOS application, combines the species distribution models with the location services built into a mobile device to provide users with a list of all plant species expected to occur in the 100 × 100 km geographic grid cell corresponding to the user's location...... in identification of species by the user. The application's ability to assemble locally relevant lists of plant species and their attributes on demand for anywhere in the Americas provides a powerful new tool for identifying, exploring, and understanding plant diversity. Mobile applications such as Plant...

  7. Biological potential of extraterrestrial materials. 2. Microbial and plant responses to nutrients in the Murchison carbonaceous meteorite

    Science.gov (United States)

    Mautner, M. N.; Conner, A. J.; Killham, K.; Deamer, D. W.

    1997-01-01

    Meteoritic materials are investigated as potential early planetary nutrients. Aqueous extracts of the Murchison C2 carbonaceous meteorite are utilized as a sole carbon source by microorganisms, as demonstrated by the genetically modified Pseudomonas fluorescence equipped with the lux gene. Nutrient effects are observed also with the soil microorganisms Nocardia asteroides and Arthrobacter pascens that reach populations up to 5 x 10(7) CFU/ml in meteorite extracts, similar to populations in terrestrial soil extracts. Plant tissue cultures of Asparagus officinalis and Solanum tuberosum (potato) exhibit enhanced pigmentation and some enhanced growth when meteorite extracts are added to partial nutrient media, but inhibited growth when added to full nutrient solution. The meteorite extracts lead to large increases in S, Ca, Mg, and Fe plant tissue contents as shown by X-ray fluorescence, while P, K, and Cl contents show mixed effects. In both microbiological and plant tissue experiments, the nutrient and inhibitory effects appear to be best balanced for growth at about 1:20 (extracted solid : H2O) ratios. The results suggest that solutions in cavities in meteorites can provide efficient concentrated biogenic and early nutrient environments, including high phosphate levels, which may be the limiting nutrient. The results also suggest that carbonaceous asteroid resources can sustain soil microbial activity and provide essential macronutrients for future space-based ecosystems.

  8. Fungal nutrient allocation in common mycorrhizal networks is regulated by the carbon source strength of individual host plants.

    Science.gov (United States)

    Fellbaum, Carl R; Mensah, Jerry A; Cloos, Adam J; Strahan, Gary E; Pfeffer, Philip E; Kiers, E Toby; Bücking, Heike

    2014-07-01

    Common mycorrhizal networks (CMNs) of arbuscular mycorrhizal (AM) fungi in the soil simultaneously provide multiple host plants with nutrients, but the mechanisms by which the nutrient transport to individual host plants within one CMN is controlled are unknown. Using radioactive and stable isotopes, we followed the transport of phosphorus (P) and nitrogen (N) in the CMNs of two fungal species to plants that differed in their carbon (C) source strength, and correlated the transport to the expression of mycorrhiza-inducible plant P (MtPt4) and ammonium (1723.m00046) transporters in mycorrhizal roots. AM fungi discriminated between host plants that shared a CMN and preferentially allocated nutrients to high-quality (nonshaded) hosts. However, the fungus also supplied low-quality (shaded) hosts with nutrients and maintained a high colonization rate in these plants. Fungal P transport was correlated to the expression of MtPt4. The expression of the putative ammonium transporter 1723.m00046 was dependent on the fungal nutrient supply and was induced when the CMN had access to N. Biological market theory has emerged as a tool with which the strategic investment of competing partners in trading networks can be studied. Our work demonstrates how fungal partners are able to retain bargaining power, despite being obligately dependent on their hosts.

  9. Temporal-spatial dynamics in orthoptera in relation to nutrient availability and plant species richness.

    Directory of Open Access Journals (Sweden)

    Rob J J Hendriks

    Full Text Available Nutrient availability in ecosystems has increased dramatically over the last century. Excess reactive nitrogen deposition is known to negatively impact plant communities, e.g. by changing species composition, biomass and vegetation structure. In contrast, little is known on how such impacts propagate to higher trophic levels. To evaluate how nitrogen deposition affects plants and herbivore communities through time, we used extensive databases of spatially explicit historical records of Dutch plant species and Orthoptera (grasshoppers and crickets, a group of animals that are particularly susceptible to changes in the C:N ratio of their resources. We use robust methods that deal with the unstandardized nature of historical databases to test whether nitrogen deposition levels and plant richness changes influence the patterns of richness change of Orthoptera, taking into account Orthoptera species functional traits. Our findings show that effects indeed also propagate to higher trophic levels. Differences in functional traits affected the temporal-spatial dynamics of assemblages of Orthoptera. While nitrogen deposition affected plant diversity, contrary to our expectations, we could not find a strong significant effect of food related traits. However we found that species with low habitat specificity, limited dispersal capacity and egg deposition in the soil were more negativly affected by nitrogen deposition levels. Despite the lack of significant effect of plant richness or food related traits on Orthoptera, the negative effects of nitrogen detected within certain trait groups (e.g. groups with limited disperse ability could be related to subtle changes in plant abundance and plant quality. Our results, however, suggest that the changes in soil conditions (where many Orthoptera species lay their eggs or other habitat changes driven by nitrogen have a stronger influence than food related traits. To fully evaluate the negative effects of nitrogen

  10. Growth, nutrient uptake and ectomycorrhizal function in Pinus sylvestris plants exposed to aluminium and heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Ahonen-Jonnarth, Ulla [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    2000-07-01

    The potential role of aluminium (Al) toxicity to trees has been of particular concern to forest owners and scientists since the early 1980's when Ulrich hypothesised that both Al and heavy metals were involved in forest dieback because of their increased concentrations in soil due to acidification. Since then, numerous studies have examined the effects of metals upon nutrient uptake by plants. However, most of these investigations have been carried out in the absence of mycorrhizal fungi, which, in most ecosystems, are crucial components in nutrient uptake by plants. The present work focused on the effects of elevated concentrations of Al and heavy metals on Scots pine (Pinus sylvestris L.) and the potential role of ectomycorrhiza in modifying these effects. Ectomycorrhizal colonisation enhanced the growth and nutrient uptake by seedlings. To some extent, colonisation also alleviated reduced nutrient uptake which was a feature of seedlings growing in the presence of the metals. This effect was particularly noticeable with respect to P uptake. In general, mycorrhizal seedlings grew better and had an improved P, K, Mg and S status compared with non-mycorrhizal seedlings. Significant differences were also found in nutrient uptake among seedlings colonised by different fungi. One fungus, Hebeloma cf. longicaudum, was more sensitive to the Al treatment than the pine seedlings. The use of the base cation / Al ratio as an indicator of the potential detrimental effects to trees to acidification and Al is discussed. The production of oxalic acid was found to increase when mycorrhizal and nonmycorrhizal seedlings were exposed to Al or Cu. Colonisation by Suillus variegatus or Rhizopogon roseolus, in particular, resulted in a marked increase. These results demonstrate that there is a capacity, especially by certain ectomycorrhizal fungi, for increased production of the metal-chelating oxalic acid when root systems are exposed to increased levels of metals. In a field

  11. Effect of mycorrhizas application on plant growth and nutrient uptake in cucumber production under field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ortas, I.

    2010-07-01

    Mycorrhizas application in horticultural production in the Eastern Mediterranean region of Turkey has been studied under field conditions for several years. The effects of different arbuscular mycorrhizal fungi (AMF) have been evaluated under field conditions for cucumber production. The parameters measured were seedling survival, plant growth and yield, and root colonization. In 1998 and 1999, Glomus mosseae and Glomus etunicatum inoculated cucumber seedlings were treated with and without P (100 kg P2O5 ha-1) application. A second experiment was set up to evaluate the response of cucumber to the inoculation with a consortia of indigenous mycorrhizae, G. mosseae, G. etunicatum, Glomus clarum, Glomus caledonium and a mixture of these four species. Inoculated and control non inoculated cucumber seedlings were established under field conditions in 1998, 2001, 2002 and 2004. Seedling quality, seedling survival under field conditions and yield response to mycorrhiza were tested. Fruits were harvested periodically; at blossom, plant leaves and root samples were taken for nutrient content and mycorrhizal colonization analysis respectively. The field experiment results showed that mycorrhiza inoculation significantly increased cucumber seedling survival, fruit yield, P and Zn shoot concentrations. Indigenous mycorrhiza inoculum was successful in colonizing plant roots and resulted in better plant growth and yield. The relative effectiveness of each of the inocula tested was not consistent in the different experiments, although inoculated plants always grew better than control no inoculated. The most relevant result for growers was the increased survival of seedlings. (Author) 20 refs.

  12. Influence of Pulsed Electromagnetic Field on Plant Growth, Nutrient Absorption and Yield of Durum Wheat

    Directory of Open Access Journals (Sweden)

    Nikolaos KATSENIOS

    2015-12-01

    Full Text Available Researchers have adopted the use of magnetic field as a new pre-sowing, environmental friendly technique. Enhancements on plant characteristics with economic impact on producer’s income could be the future of a modern, organic and sustainable agriculture. A field experiment was established at Soil Science Institute of Athens, Lycovrissi, Greece, in the winter of 2014. Two durum wheat cultivars were used. It was a pot experiment with 6 treatments (2 cultivars with 3 magnetic field time exposure. The seeds were treated using a PAPIMI electromagnetic field generator for 0, 30 and 45 minutes one day before planting. The experiment followed a completely randomized design with six treatments and 30 replications. The aim of this study was to evaluate the positive effect of magnetic field pre-sowing treatment in a wide range of plant measurements, including yield. The influence of pulsed electromagnetic field on two varieties of durum wheat seeds showed some statistically significant differences at the 0.05 level in growth measurements, physiological measurements and root growth measurements. Plant tissue analysis showed that magnetic field treatments had higher values than control in total nitrogen, phosphorus, potassium, magnesium, copper (only MF-45, zinc (only MF-30 and boron content, although values showed statistically significant differences only in total nitrogen. The results indicate that this innovative technique can increase the yield of durum wheat, through enhanced absorption of nutrients. Pre-sowing treatment of the seeds leads to vigorous plant growth that are more productive.

  13. Control and Modeling of Plant Growth : A versatile system for mineral nutrient addition and feed-back monitoring

    OpenAIRE

    Wiese, Benjamin

    2011-01-01

    Studying plants under controlled environmental conditions is a key component of current research. This thesis concentrates on the study of plant growth under nutrient-limiting condi-tions. The first objective is the design and construction of a prototype of a system which is able to supply nutrient so-lutions of prescribed time-dependent concentration to labo-ratory plants. The system, once configured via a PC, oper-ates fully automatically without the need for human inter-ference. The hardwa...

  14. Biomass accumulation and nutrient uptake of 16 riparian woody plant species in Northeast China

    Institute of Scientific and Technical Information of China (English)

    Shuai Yu; Wei Chen; Xingyuan He; Zhouli Liu; Yanqing Huang

    2014-01-01

    Our research focused on eutrophication control and species screening for riparian zone vegetation restoration in the upstream reach of the Hun River. We studied 16 hardwood plant species to investigate nutrient concentrations and nitrogen and phosphorus accumulations. After about 120 days of growth in pots, these 16 species varied in dry matter biomass, ranging from 15.13 to 637.16 g. Total nitrogen (TN) and total phosphorus (TP) concentrations and distribution in roots, stems and foliage differed both within and between tested species. Mean TN and TP accumulation ranged from 0.167 to 14.730 g per plant and from 0.016 to 1.20 g, respectively. All 16 species, but especially Lespedeza bicolor, Robinia pseudoacacia and Sorbaria sorbifolia had strong potential to remove TN and TP from soil and could be widely utilized for the restora-tion of destroyed riparian zones in northeast China.

  15. Troubleshooting a Full-scale Wastewater Treatment Plant for Biological Nutrient Removal

    Directory of Open Access Journals (Sweden)

    Oleyiblo Oloche James

    2014-01-01

    Full Text Available The International Association of Water Quality (IAWQ Activated Sludge Model No.2 (ASM2 was applied to troubleshoot an existing underperforming full-scale wastewater treatment plant (WWTP built for biological nutrient removal. The WWTP is operated in a 3-stage pho-redox process configuration (A2O. This study was undertaken with the aim of finding optimal operating conditions that will meet TP and TN concentration requirements in the effluent of the WWTP under study without the use of either chemical or external carbon sources and also to verify the applicability, capability and predictability of ASM2 as implemented in STOAT software. ASM2 was successfully used to troubleshoot bottle neck areas and to define the operational schedule for optimal performance of the wastewater treatment plant. Consequently, the costs of chemical and external carbon sources were eliminated and the effect of residual chemicals on the environment reduced.

  16. Co-composted biochar can promote plant growth by serving as a nutrient carrier: first mechanistic insights

    Science.gov (United States)

    Kammann, Claudia; Haider, Ghulam; Messerschmidt, Nicole; Schmidt, Hans-Peter; Koyro, Hans-Werner; Steffens, Diedrich; Clough, Timothy; Müller, Christoph

    2014-05-01

    Pyrogenic carbon (biochar) offers considerable potential for carbon capture (CCSS) and soil storage and meta-analysis suggests that it can significantly reduce soil N2O emissions. Freshly produced biochars, however, do not always have yield-improving effects; pure, production-fresh biochar seems to 'claim' some nutrients initially from soil, particularly nitrogen, although the mechanisms are unclear to date. Hence, combining biochar with organic nutrient-rich materials and waste streams may be a promising strategy to enable CCSS by yield improvements, which may enable economically feasible biochar use in agriculture. We explored the potential of organically post-treated biochar to act as a nutrient carrier and thus to increase its socio-economic value as beneficial soil amendment with associated CCSS value. In a first proof-of-concept study the effects of untreated biochar were compared to those of co-composted biochar, combined with stepwise improved nutritional regimes (+/- compost; +/- mineral-N application). While the untreated biochar reduced plant growth under N-limiting conditions, or at best did not reduce it, the co-composted biochar always significantly stimulated plant growth. The relative stimulation was largest with the lowest nutrient additions (305% versus 61% of control with untreated biochar). Subsequent electro-ultra-filtration analyses revealed that the co-composted but not the untreated biochar carried considerable amounts of easily extractable as well as more strongly sorbed plant nutrients, in particular nitrate and phosphorus. Nevertheless the co-composted N-rich biochar still sorbed 15N labelled NH4+ or NO3- when present in the soil, and again released it to growing barley plants. We will report on the relationship between particle size, increased nutrient content, and plant accessibility of the nutrients associated with the co-composted biochar, and analyse the extent to which the strongly sorbed nutrients on the biochar may be 'invisible

  17. Relationships between nutrient-related plant traits and combinations of soil N and P fertility measures.

    Directory of Open Access Journals (Sweden)

    Yuki Fujita

    Full Text Available Soil fertility and nutrient-related plant functional traits are in general only moderately related, hindering the progress in trait-based prediction models of vegetation patterns. Although the relationships may have been obscured by suboptimal choices in how soil fertility is expressed, there has never been a systematic investigation into the suitability of fertility measures. This study, therefore, examined the effect of different soil fertility measures on the strength of fertility-trait relationships in 134 natural plant communities. In particular, for eight plot-mean traits we examined (1 whether different elements (N or P have contrasting or shared influences, (2 which timescale of fertility measures (e.g. mineralization rates for one or five years has better predictive power, and (3 if integrated fertility measures explain trait variation better than individual fertility measures. Soil N and P had large mutual effects on leaf nutrient concentrations, whereas they had element-specific effects on traits related to species composition (e.g. Grime's CSR strategy. The timescale of fertility measures only had a minor impact on fertility-trait relationships. Two integrated fertility measures (one reflecting overall fertility, another relative availability of soil N and P were related significantly to most plant traits, but were not better in explaining trait variation than individual fertility measures. Using all fertility measures together, between-site variations of plant traits were explained only moderately for some traits (e.g. 33% for leaf N concentrations but largely for others (e.g. 66% for whole-canopy P concentration. The moderate relationships were probably due to complex regulation mechanisms of fertility on traits, rather than to a wrong choice of fertility measures. We identified both mutual (i.e. shared and divergent (i.e. element-specific and stoichiometric effects of soil N and P on traits, implying the importance of explicitly

  18. Relationships between nutrient-related plant traits and combinations of soil N and P fertility measures.

    Science.gov (United States)

    Fujita, Yuki; van Bodegom, Peter M; Witte, Jan-Philip M

    2013-01-01

    Soil fertility and nutrient-related plant functional traits are in general only moderately related, hindering the progress in trait-based prediction models of vegetation patterns. Although the relationships may have been obscured by suboptimal choices in how soil fertility is expressed, there has never been a systematic investigation into the suitability of fertility measures. This study, therefore, examined the effect of different soil fertility measures on the strength of fertility-trait relationships in 134 natural plant communities. In particular, for eight plot-mean traits we examined (1) whether different elements (N or P) have contrasting or shared influences, (2) which timescale of fertility measures (e.g. mineralization rates for one or five years) has better predictive power, and (3) if integrated fertility measures explain trait variation better than individual fertility measures. Soil N and P had large mutual effects on leaf nutrient concentrations, whereas they had element-specific effects on traits related to species composition (e.g. Grime's CSR strategy). The timescale of fertility measures only had a minor impact on fertility-trait relationships. Two integrated fertility measures (one reflecting overall fertility, another relative availability of soil N and P) were related significantly to most plant traits, but were not better in explaining trait variation than individual fertility measures. Using all fertility measures together, between-site variations of plant traits were explained only moderately for some traits (e.g. 33% for leaf N concentrations) but largely for others (e.g. 66% for whole-canopy P concentration). The moderate relationships were probably due to complex regulation mechanisms of fertility on traits, rather than to a wrong choice of fertility measures. We identified both mutual (i.e. shared) and divergent (i.e. element-specific and stoichiometric) effects of soil N and P on traits, implying the importance of explicitly

  19. Carbon sequestration and plant nutrients in soil in different land types in Thingvellir Iceland

    Science.gov (United States)

    Svavarsdóttir, María; Gísladóttir, Guðrún; Mankasingh, Utra

    2015-04-01

    Special properties of volcanic soils (andisol) that is most common in Iceland can sequestrate considerably more carbon (C) that other types of soils. A mellow developed andisol with natural ecosystem such as birch forest or grass- and heathland is presumably to be fertile and sequestrate a lot of carbon. Coniferous tree species have been imported to Iceland for large scale utilisation in Icelandic forestry and is therefore an imported species/ecosystem. Abroad it has been noticed that coniferous trees acidify soil and change the properties of the soil so other species cannot thrive in it. The Icelandic Forest service is aiming tenfold the coverage of forests in Iceland before the year 2100 but about 50% of tree species that the institution uses is coniferous species. It is therefore important to research the soil due to the plant types that are planted in the soil. The aim of this project is to compare soil properties, soil nutrients and soil sequestration in heathland, birch forest and coniferous forest in Thingvellir national park in Iceland. Heathland and birch forest represent the natural ecosystem but coniferous forest imported ecosystem. Carbon (C) in soil will be measured, proportion of carbon and nitrogen (C:N), respiration from soil (CO2) and live green biomass and organic matter in the soil. The speed of decomposition of organic matter will be estimated. Important nutrients, pH and cation exchange capacity will be measured among other physical properties as bulk density, grain size and water holding capacity of the soil.

  20. Advanced nutrient root-feeding system for conveyor-type cylindrical plant growth facilities for microgravity

    Science.gov (United States)

    Berkovich, Yu. A.; Krivobok, N. M.; Krivobok, A. S.; Smolyanina, S. O.

    2016-02-01

    A compact and reliable automatic method for plant nutrition supply is needed to monitor and control space-based plant production systems. The authors of this study have designed a nutrient root-feeding system that minimizes and regulates nutrient and water supply without loss of crop yields in a space greenhouse. The system involves an ion-exchange fibrous artificial soil (AS) BIONA-V3TM as the root-inhabited medium; a pack with slow-release fertilizer as the main source of nitrogen, phosphorus, and potassium; and a cartridge with granular mineral-rich ionite (GMRI) as a source of calcium, magnesium, sulfur, and iron. A controller equipped with an electrical conductivity meter controls the solution flow and concentration of the solution in the mixing tank at specified values. Experiments showed that the fibrous AS-stabilized pH of the substrate solution within the range of 6.0-6.6 is favorable to the majority of crops. The experimental data confirmed that this technique allowed solution preparation for crops in space greenhouses by means of pumping water through the cartridge and minimization of the AS stock onboard the space vehicle.

  1. Conservation of soil, water and nutrients in surface runoff using riparian plant species.

    Science.gov (United States)

    Srivastava, Prabodh; Singh, Shipra

    2012-01-01

    Three riparian plant species viz. Cynodon dactylon (L.) Pers., Saccharum bengalensis Retz. and Parthenium hysterophorus L. were selected from the riparian zone of Kali river at Aligarh to conduct the surface runoff experiment to compare their conservation efficiencies for soil, water and nutrients (phosphorus and nitrogen). Experimental plots were prepared on artificial slopes in botanical garden and on natural slopes on study site. Selected riparian plant species showed the range of conservation values for soil and water from 47.11 to 95.22% and 44.06 to 72.50%, respectively on artificial slope and from 44.53 to 95.33% and 48.36 to 73.15%, respectively on natural slope. Conservation values for phosphorus and nitrogen ranged from 40.83 to 88.89% and 59.78 to 82.22%, respectively on artificial slope and from 50.01 to 90.16% and 68.07 to 85.62%, respectively on natural slope. It was observed that Cynodon dactylon was the most efficient riparian species in conservation of soil, water and nutrients in surface runoff.

  2. Complexity of nutrient use efficiency in plants : Metabolic and environmental control at a whole plant perspective

    NARCIS (Netherlands)

    Reich, Martin

    2015-01-01

    To meet the increasing demand for food of a fast growing world population, agriculture needs to be more productive. During last century the agricultural production was worldwide strongly improved by plant breeding and the use of pesticides and fertilizers. This has also resulted in negative environm

  3. A Novel Type of Nutritional Ant–Plant Interaction: Ant Partners of Carnivorous Pitcher Plants Prevent Nutrient Export by Dipteran Pitcher Infauna

    Science.gov (United States)

    Scharmann, Mathias; Thornham, Daniel G.; Grafe, T. Ulmar; Federle, Walter

    2013-01-01

    Many plants combat herbivore and pathogen attack indirectly by attracting predators of their herbivores. Here we describe a novel type of insect–plant interaction where a carnivorous plant uses such an indirect defence to prevent nutrient loss to kleptoparasites. The ant Camponotus schmitzi is an obligate inhabitant of the carnivorous pitcher plant Nepenthes bicalcarata in Borneo. It has recently been suggested that this ant–plant interaction is a nutritional mutualism, but the detailed mechanisms and the origin of the ant-derived nutrient supply have remained unexplained. We confirm that N. bicalcarata host plant leaves naturally have an elevated 15N/14N stable isotope abundance ratio (δ15N) when colonised by C. schmitzi. This indicates that a higher proportion of the plants’ nitrogen is insect-derived when C. schmitzi ants are present (ca. 100%, vs. 77% in uncolonised plants) and that more nitrogen is available to them. We demonstrated direct flux of nutrients from the ants to the host plant in a 15N pulse-chase experiment. As C. schmitzi ants only feed on nectar and pitcher contents of their host, the elevated foliar δ15N cannot be explained by classic ant-feeding (myrmecotrophy) but must originate from a higher efficiency of the pitcher traps. We discovered that C. schmitzi ants not only increase the pitchers' capture efficiency by keeping the pitchers’ trapping surfaces clean, but they also reduce nutrient loss from the pitchers by predating dipteran pitcher inhabitants (infauna). Consequently, nutrients the pitchers would have otherwise lost via emerging flies become available as ant colony waste. The plants’ prey is therefore conserved by the ants. The interaction between C. schmitzi, N. bicalcarata and dipteran pitcher infauna represents a new type of mutualism where animals mitigate the damage by nutrient thieves to a plant. PMID:23717446

  4. Seasonal variations and effects of nutrient applications on N and P and microbial biomass under two temperate heathland plants

    DEFF Research Database (Denmark)

    Nielsen, Pia Lund; Andresen, Louise Christoffersen; Michelsen, Anders;

    2009-01-01

    Eutrofication is a threat against nutrient-poor habitats as increased amounts of nutrients in ecosystems may cause changes in the vegetation. Nitrogen (N) deposition leads to conversion of Calluna heathlands into graminoid dominated heath, but low availability of P may hinder or slow down...... this process. In this study the soil properties under two dominant heathland plants, the dwarf shrub Calluna vulgaris and the grass Deschampsia flexuosa, were investigated, with focus on nutrient content in the organic top soil and soil microbes during the main growing season and effects of nutrient amendments....... The microbial biomass on the other hand was positively related to soil water content in fertilized plots indicating that this was due to an indirect effect of enhanced nutrient availability. Microbial N and P pools were respectively 1000 and 100 times higher than the pool of inorganic N and P, and microbes...

  5. SOIL-PLANT NUTRIENT INTERACTIONS IN TWO MANGROVE AREAS AT SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Ana Paula Lang Martins Madi

    2015-11-01

    Full Text Available ABSTRACTMangrove forests have a simple architecture. They shelter a few number of arboreal species that grow in a saline environment subject to tidal activity. The research objective was to evaluate possible interactions between physical-chemical soil attributes and plant-leaf nutrient concentrations of different mangrove species. Different mangrove species growing in the same soil, and the same mangrove species growing in two different soil classes were evaluated as to their leaf nutrient concentration patterns. The study was carried out in mangrove areas of the State of Paraná, southern Brazil, in two distinct soil classes: HISTOSOL THIOMORPHIC Salic sodic and GLEYSOL THIOMORPHIC Salic sodic; and three different species: Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle. Two subareas were delimited within each area from which soil and leaf samples were collected. Samplings from five individuals of each dominant mangrove species were taken from the soil (0-10 cm deep under each tree crown projection. The data was submitted to statistical analysis using a set of simple and multivariate analysis in order to determine possible differences among mangrove species leaf nutrient concentrations, and whether these differences might be correlated with the soil attributes or not. The results exposed that the nutritional state of the mangrove species is different and independent form the soil attributes in which they grow. Few correlations were found among leaf nutrient concentrations and soil attributes, suggesting differential selective nutrient uptake among species.RESUMENLos manglares son bosques de arquitectura simple que albergan pocas especies arbóreas, creciendo en un ambiente salino sometido a la influencia de las mareas. El objetivo de este trabajo fue evaluar las posibles interacciones entre las propiedades fisicoquímicas del suelo y la concentración de nutrientes en hojas de diferentes especies de mangle. Se investigó si

  6. Concentration is not enough to evaluate accumulation of heavy metals and nutrients in plants.

    Science.gov (United States)

    Vymazal, Jan

    2016-02-15

    Wetland plants produce high aboveground biomass and possess the ability to accumulate heavy metals and nutrients. This ability is used for phytoremediation purposes including removal of nutrients and heavy metals from polluted waters. The concentrations of heavy metals are usually much higher in the belowground then in aboveground biomass, especially in roots which are primary sites of uptake. This may lead to the conclusion that accumulation of heavy metals is higher in the belowground biomass. However, in case the aboveground is much higher than belowground biomass the accumulation could be higher in the aboveground biomass. Concentration of nitrogen and phosphorus is always higher in leaves than in stems. However, the stem biomass is often much higher in robust emergent species such as Phragmites australis and therefore, more nutrients can be stored in stems. The examples shown in this communication clearly reveal that to evaluate properly the accumulation of heavy metals and nutrients in particular plant compartment biomass amount must be taken into consideration. In the first study, concentrations of Cd, Cr and Hg in Phalaris arundinacea belowground/aboveground biomass were 150/80 μg/kg, 5420/228 μg/kg and 38/18 μg/kg. The high aboveground biomass (1196 g/m(2)) and low belowground biomass (244 g/(2)) resulted in much higher accumulation of Cd and Hg in aboveground biomass (96 μg/m(2) and 21.2 μg/m(2), respectively) than in belowground biomass (36 μg/m(2) and 9.3 μg/m(2), respectively). Only for chromium, belowground accumulation (1312 μg/m(2)) was higher than aboveground accumulation (272 μg/m(2)). In the second study, both nitrogen and phosphorus concentrations were higher (26.7 mg/g and 749 mg/kg, respectively) in leaves than in stems (8.2mg/g and 534 mg/kg, respectively) of P. australis. The higher biomass of stems (1835 g/m(2)) than leaves (967 g/m(2)) resulted in higher accumulation of nitrogen but lower accumulation of phosphorus in leaves as

  7. Simple procedure for nutrient analysis of coffee plant with energy dispersive X-ray fluorescence spectrometry (EDXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Tezotto, Tiago; Favarin, Jose Laercio; Neto, Ana Paula; Azevedo, Ricardo Antunes, E-mail: tiago.tezotto@usp.br [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil); Gratao, Priscila Lupino [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP/ FCAV), Jaboticabal, SP (Brazil). Dept. de Biologia Aplicada a Agropecuaria; Mazzafera, Paulo [Universidade Estadual de Campinas (UNICAMP/IB), SP (Brazil). Dept. Biologia Vegetal

    2013-07-15

    Nutrient analysis is used to estimate nutrient content of crop plants to manage fertilizer application for sustained crop production. Direct solid analysis of agricultural and environmental samples by energy dispersive X-ray fluorescence spectrometry (EDXRF) was chosen as alternative technique to evaluate the simultaneous multielemental quantification of the most important essential elements in coffee (Coffea arabica L.) plants. Inductively coupled plasma atomic emission spectrometry and certified reference materials made from leaves were used to calibrate and check the trueness of EDXRF method for the determination of the concentration of several nutrients in coffee leaves and branches. Fluorescence spectrometry proved to be advantageous and presented low cost as loose powder samples could be used. Samples collected from a field experiment where coffee plants were treated with excess of Ni and Zn were used to verify the practical application of the method. Good relationships were achieved between certified values and data obtained by EDXRF, with recoveries ranging from 82 to 117 %.(author)

  8. Multiple soil nutrient competition between plants, microbes, and mineral surfaces: model development, parameterization, and example applications in several tropical forests

    Directory of Open Access Journals (Sweden)

    Q. Zhu

    2015-03-01

    Full Text Available Soil is a complex system where biotic (e.g., plant roots, micro-organisms and abiotic (e.g., mineral surfaces consumers compete for resources necessary for life (e.g., nitrogen, phosphorus. This competition is ecologically significant, since it regulates the dynamics of soil nutrients and controls aboveground plant productivity. Here we develop, calibrate, and test a nutrient competition model that accounts for multiple soil nutrients interacting with multiple biotic and abiotic consumers. As applied here for tropical forests, the Nutrient COMpetition model (N-COM includes three primary soil nutrients (NH4+, NO3−, and POx (representing the sum of PO43−, HPO42−, and H2PO4− and five potential competitors (plant roots, decomposing microbes, nitrifiers, denitrifiers, and mineral surfaces. The competition is formulated with a quasi-steady-state chemical equilibrium approximation to account for substrate (multiple substrates share one consumer and consumer (multiple consumers compete for one substrate effects. N-COM successfully reproduced observed soil heterotrophic respiration, N2O emissions, free phosphorus, sorbed phosphorus, and free NH4+ at a tropical forest site (Tapajos. The overall model posterior uncertainty was moderately well constrained. Our sensitivity analysis revealed that soil nutrient competition was primarily regulated by consumer-substrate affinity rather than environmental factors such as soil temperature or soil moisture. Our results imply that the competitiveness (from most to least competitive followed this order: (1 for NH4+, nitrifiers ~ decomposing microbes > plant roots, (2 for NO3−, denitrifiers ~ decomposing microbes > plant roots, (3 for POx, mineral surfaces > decomposing microbes ~ plant roots. Although smaller, plant relative competitiveness is of the same order of magnitude as microbes. We then applied the N-COM model to analyze field nitrogen and phosphorus perturbation experiments in two tropical forest

  9. Influence of Nitrogen Sources and Plant Growth-Promoting Rhizobacteria Inoculation on Growth, Crude Fiber and Nutrient Uptake in Squash (Cucurbita moschata Duchesne ex Poir.) Plants

    OpenAIRE

    Alice I. TCHIAZE; Victor D. TAFFOUO; Henri FANKEM; Kenne, Martin; Régis BAZIRAMAKENGA; Ekodeck, Georges E.; Antoun, Hani

    2016-01-01

    Plant growth promoting rhizobacteria (PGPR, B) have immense potential application in sustainable agriculture as ecofriendly biofertilizers and biopesticides. In this study, the effects of three nitrogen (N) sources (NO3-, NH4+ and NO3NH4) and PGPR on growth, crude fiber and nutrient uptake were investigated in squash plants. Some growth parameters [root dry weight (RDW), shoot dry weight (SDW), total plant dry weight (PDW), number of leaves (NL), shoot length (SL), stem diameter (SD) and numb...

  10. Global change and response of coastal dune plants to the combined effects of increased sand accretion (burial) and nutrient availability.

    Science.gov (United States)

    Frosini, Silvia; Lardicci, Claudio; Balestri, Elena

    2012-01-01

    Coastal dune plants are subjected to natural multiple stresses and vulnerable to global change. Some changes associated with global change could interact in their effects on vegetation. As vegetation plays a fundamental role in building and stabilizing dune systems, effective coastal habitat management requires a better understanding of the combined effects of such changes on plant populations. A manipulative experiment was conducted along a Mediterranean dune system to examine the individual and combined effects of increased sediment accretion (burial) and nitrogen enrichment associated with predicted global change on the performance of young clones of Sporobolus virginicus, a widespread dune stabilizing species. Increased burial severity resulted in the production of taller but thinner shoots, while nutrient enrichment stimulated rhizome production. Nutrient enrichment increased total plant biomass up to moderate burial levels (50% of plant height), but it had not effect at the highest burial level (100% of plant height). The effects of such factors on total biomass, shoot biomass and branching were influenced by spatial variation in natural factors at the scale of hundreds of metres. These results indicate that the effects of burial and nutrient enrichment on plant performance were not independent. Their combined effects may not be predicted by knowing the individual effects, at least under the study conditions. Under global change scenarios, increased nutrient input could alleviate nutrient stress in S. virginicus, enhancing clonal expansion and productivity, but this benefit could be offset by increased sand accretion levels equal or exceeding 100% of plant height. Depletion of stored reserves for emerging from sand could increase plant vulnerability to other stresses in the long-term. The results emphasize the need to incorporate statistical designs for detecting non-independent effects of multiple changes and adequate spatial replication in future works to

  11. Bioremoval of heavy metals and nutrients from sewage plant by Anabaena oryzae and Cyanosarcina fontana.

    Science.gov (United States)

    Fawzy, Mustafa A; Issa, Ahmed A

    2016-01-01

    The present study demonstrated the growth of two species of cyanobacteria on wastewater isolated from sewage plant in Aswan, Egypt. We evaluated their efficiency for eliminating nitrogen, phosphorus, chemical oxygen demand (COD) and heavy metals (Fe(2+), Pb(2+), Cu(2+), and Mn(2+)). The growth of Cyanosarcina fontana has supported wastewater as a growth medium than Anabaena oryzae compared to standard medium. The nutrients concentration such as COD, NO3-N and PO4-P were decreased by the growth of A. oryzae and C. fontana in the wastewater after primary settling and centrate. However, the reduction of COD was less efficient than the other nutrients. The reduction percentage of COD, NO3-N and PO4-P reached 39.3, 84.1 and 90.7% as well as 54.6, 83.1, and 89.8%, in cultures of A. oryzae and C. fontana grown in the wastewater after primary settling, respectively. The reduction amounted to 10.1, 76.8, and 63.0% by A. oryzae and 43.2, 62.1, and 74.8% by C. fontana, grown in the centrate, respectively. Cyanobacteria species have the ability to accumulate the heavy metals from the wastewater to level far than the exceeding metal level in the water. Whereas, the heavy metals biosorption performance of C. fontana was higher in accumulating Fe(2+) (93.95%), Pb(2+) (81.21%), Cu(2+) (63.9%), and Mn(2+) (48.49%) compared to A. oryzae. The biosorption ability is dependent on the nature of the adsorbent studied and the type of wastewater treated. Therefore, removal of heavy metals and nutrients by the tested algae is strongly recommended as a powerful technique for the removal of pollutants from wastewater.

  12. Seasonal amounts of nutrients in Western cherry fruit fly (Diptera: Tephritidae) and their relation to nutrient availability on cherry plant surfaces.

    Science.gov (United States)

    Yee, Wee L; Chapman, Peter S

    2008-10-01

    Relatively little is known about the nutritional ecology of fruit flies in the genus Rhagoletis. In this study, nutrient amounts in male and female western cherry fruit fly, Rhagoletis indifferens Curran, and availability of nitrogen and sugar on surfaces of leaves, fruit, and extrafloral nectaries (EFNs) of sweet cherry trees, were determined from late May to late June 2005 and of sugar from EFNs from mid-May to late June 2007 in Washington state. Protein amounts in male and female flies did not differ over the season. Nitrogen was present on leaves, fruit, and EFNs during the sampling period, but amounts on leaves and fruit were lower in late May than the rest of the season. Sugar amounts in flies did not differ over the season. Sugar was present on leaf, fruit, and EFN surfaces all season, but amounts on all three were lower in late May than later in the season. Fructose and glucose were the predominant sugars on all plant surfaces, but sucrose was also present in nectar from EFNs. In outdoor and field cage experiments in 2004 and 2006, more flies survived when cherry branches with leaves and fruit were present than absent. Results suggest that R. indifferens maintains stable protein and sugar levels throughout the season because sufficient amounts of nutrients are found in cherry trees during this time and that increases in nutrient availability caused by ripening and damaged cherries later in the season do not result in increased amounts of nutrients in flies.

  13. Intraspecific trait variation drives functional responses of old-field plant communities to nutrient enrichment.

    Science.gov (United States)

    Siefert, Andrew; Ritchie, Mark E

    2016-05-01

    Environmental changes are expected to shift the distribution of functional trait values in plant communities through a combination of species turnover and intraspecific variation. The strength of these shifts may depend on the availability of individuals with trait values adapted to new environmental conditions, represented by the functional diversity (FD) of existing community residents or dispersal from the regional species pool. We conducted a 3-year nutrient- and seed-addition experiment in old-field plant communities to examine the contributions of species turnover and intraspecific variation to community trait shifts, focusing on four key plant functional traits: vegetative height, leaf area, specific leaf area (SLA), and leaf dry matter content (LDMC). We further examined the influence of initial FD and seed availability on the strength of these shifts. Community mean height, leaf area, and SLA increased in response to fertilization, and these shifts were driven almost entirely by intraspecific variation. The strength of intraspecific shifts in height and leaf area was positively related to initial intraspecific FD in these traits. Intraspecific trait responses to fertilization varied among species, with species of short stature displaying stronger shifts in SLA and LDMC but weaker shifts in leaf area. Trait shifts due to species turnover were generally weak and opposed intraspecific responses. Seed addition altered community taxonomic composition but had little effect on community trait shifts. These results highlight the importance of intraspecific variation for short-term community functional responses and demonstrate that the strength of these responses may be mediated by community FD.

  14. Investigation of the Biomass and Nutrient Content of Green Manuring Plants as Second Crops in Hungary

    Directory of Open Access Journals (Sweden)

    Peter MIKO

    2012-05-01

    Full Text Available The growth, and the development and trends of the nutrient content parameters of three different plant species (Phacelia tanacecifolia,Sinapis alba, Raphanus sativus grown as secondary crops for green manure, as a function of two different fertiliser doses (0 kg/ha N; 50kg/ha N, was studied under unfavourable site conditions at the Crop Production and Biomass Utilisation Demonstration Centre of theSzent István University, Gödöllő, Hungary. The application of the small, 50 kg/ha dose of nitrogen increased the biomass yield in eachcase, to 2.78-3.11 times that of the control field. The dry matter content of the produce increased only by 2.11-2.66 times, as the watercontent of the green manure plants also increased as a result of the nitrogen supplement. The increased amount of nitrogen boosted theavailability of all of the other macro elements for the plants. In view of the present findings it can be recommend the application of somenitrogen fertiliser in the given site before growing some crop for use as green manure in all cases but where the straw after cereals is left onthe soil surface nitrogen should be applied to alleviate the pentosan effect and to increase the uptake of macro elements.

  15. Comparison of plant nutrient and environmental soil tests to predict Pb in urban soils.

    Science.gov (United States)

    Minca, Kristen Kathleen; Basta, Nicholas Thomas

    2013-02-15

    Most urban soils are not tested for Pb because of the high costs associated with sampling and laboratory analysis of soil contaminants. However, soil testing for plant nutrients is inexpensive and routinely performed for agricultural soils used for food production. The objectives of this study are to determine the ability of 1 M HNO(3), Mehlich 3, and Modified Morgan soil tests to predict total Pb and other contaminants in urban soils. Total Pb was determined from 65 urban vacant residential lots being considered for urban gardens and food production in Cleveland, OH. Extractable Pb was determined using common soil nutrient test methods Mehlich 3 and Modified Morgan extraction, and a 1M HNO(3) extraction. Significant linear regressions between total Pb and Mehlich 3 (r(2)=0.83), 1M HNO(3) (r(2)=0.92), and Modified Morgan (r(2)=0.77) in study soils were found. Most commercial and university soil testing labs use Mehlich 3 which could be implemented as a screening tool for soil Pb, Cu, and Zn. The Mehlich 3 soil test is widely used and is relatively inexpensive (<$15). Our results show that total Pb can be conservatively estimated by the following equation Total Pb (mg kg(-1))=Mehlich 3 Pb (mg kg(-1))×2. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Content of nutrient and antinutrient in edible flowers of wild plants in Mexico.

    Science.gov (United States)

    Sotelo, Angela; López-García, Semeí; Basurto-Peña, Francisco

    2007-09-01

    Nutrient and antinutritional/toxic factors present in some edible flowers consumed in Mexico were determined. The edible flowers were: Agave salmiana, Aloe vera, Arbutus xalapensis, Cucurbita pepo (cultivated), Erythrina americana, Erythrina caribaea, Euphorbia radians benth and Yucca filifera. The nutrient content in the flowers studied is similar to that of the edible leaves and flowers studied mainly in Africa. The moisture content of the flowers varied from 860 to 932 g kg(-1). Crude protein (CP) was between 113 to 275 g kg(-1) DM, crude fiber, 104 to 177 g kg(-1) DM and the nitrogen free extract, between 425 to 667 g kg(-1) DM. The highest chemical score (CS) was found in E. americana and A. salmiana; in five samples the limiting amino acid was lysine, and in three of them it was tryptophan. Trypsin inhibitors and hemaglutinnins had a very low concentration. Alkaloids were present in both the Erythrina species and the saponins in A. salmiana and Y. filifera. Cyanogenic glucosides were not found in the studied flowers. The traditional process of preparing these specific flowers before consumption is by cooking them and discarding the broth; in this way the toxic substances are diminished or eliminated. These edible flowers from wild plants consumed in local areas of the country play an important role in the diet of the people at least during the short time of the season where they are blooming.

  17. Acute methemoglobinemia with hemolytic anemia following bio-organic plant nutrient compound exposure: Two case reports.

    Science.gov (United States)

    Malkarnekar, Santoshi Balkrishna; Anjanappa, Raveesha; Naveen, L; Kiran, B G

    2014-02-01

    Two young women, were reffered to our hospital on two different occasions with history of breathlessness and mental confusion, following consumption of two different bio-organic plant nutrient compounds with a suicidal intent. On examination, they had cyanotic mucous membranes, and their blood samples showed the classic 'dark chocolate brown' appearance. Work up revealed cyanosis unresponsive to oxygen supplementation and absence of cardiopulmonary abnormality. Pulse oximetry revealed saturation of 75% in case 1 and 80% in case 2, on 8 liters oxygen supplementation via face masks, although their arterial blood gas analysis was normal, suggestive of "saturation gap". Methemoglobinemia was suspected based on these findings and was confirmed by Carbon monoxide-oximetry (CO-oximetry). Methylene blue was administered and the patients showed dramatic improvement. Both the patients developed evidence of hemolysis approximately 72 hours following admission which improved with blood transfusion and supportive treatment. The patients were eventually discharged without any neurological sequalae.

  18. Acute methemoglobinemia with hemolytic anemia following bio-organic plant nutrient compound exposure: Two case reports

    Directory of Open Access Journals (Sweden)

    Santoshi Balkrishna Malkarnekar

    2014-01-01

    Full Text Available Two young women, were reffered to our hospital on two different occasions with history of breathlessness and mental confusion, following consumption of two different bio-organic plant nutrient compounds with a suicidal intent. On examination, they had cyanotic mucous membranes, and their blood samples showed the classic ′dark chocolate brown′ appearance. Work up revealed cyanosis unresponsive to oxygen supplementation and absence of cardiopulmonary abnormality. Pulse oximetry revealed saturation of 75% in case 1 and 80% in case 2, on 8 liters oxygen supplementation via face masks, although their arterial blood gas analysis was normal, suggestive of "saturation gap". Methemoglobinemia was suspected based on these findings and was confirmed by Carbon monoxide-oximetry (CO-oximetry. Methylene blue was administered and the patients showed dramatic improvement. Both the patients developed evidence of hemolysis approximately 72 hours following admission which improved with blood transfusion and supportive treatment. The patients were eventually discharged without any neurological sequalae.

  19. Effects of soil-plant system change on ecohydrology during revegetation for mobile dune stabilization, Chinese arid desert

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Soil-plant systems play an important role in sand fixing and surface protection in the arid desert of China. This study examines the ecohydrological responses after a soil-plant system change for mobile dune stabilization by using a series of soil hydrological experiments and ecological investigation. The study results showed that decades of succession of soil-plant system has endangered the stability of the protection system. With the accumulated water and nutrient, a bio-logical system develops in a thinner and thinner surface soil. Redistribution of precipitation has changed completely in the ecosystem. In 3-15 mm of soil, a high capacity of crust water retention ultimately limits most rainfall from infiltrating below 10-20 cm deep. When that takes place, lower plants begin to compete for water with grasses and shrubs. A drought horizon forms in 20-500 cm depth with shrub transpiration. Artificial shrubs with deep roots obtain hardly rainfall supply and are gradually eliminated from the protection system. All changes in water environment affect the structure and func-tion and stabilization of whole protection systems. It is necessary to establish a relatively stable water environment by managing the soil-plant system for constructing a sustainable protective system in arid desert.

  20. Relationship of soybean aphid (Hemiptera: Aphididae) to soybean plant nutrients, landscape structure, and natural enemies.

    Science.gov (United States)

    Noma, Takuji; Gratton, Claudio; Colunga-Garcia, Manuel; Brewer, Michael J; Mueller, Emily E; Wyckhuys, Kris A G; Heimpel, George E; O'Neal, Matthew E

    2010-02-01

    In the north central United States, populations of the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), are highly variable across space, complicating effective aphid management. In this study we examined relationships of plant nutrients, landscape structure, and natural enemies with soybean aphid abundance across Iowa, Michigan, Minnesota, and Wisconsin, representing the range of conditions where soybean aphid outbreaks have occurred since its introduction. We sampled soybean aphid and its natural enemies, quantified vegetation land cover and measured soybean nutrients (potassium [K] and nitrogen [N]) in 26 soybean sites in 2005 and 2006. Multiple regression models found that aphid abundance was negatively associated with leaf K content in 2005, whereas it was negatively associated with habitat diversity (Simpson's index) and positively associated with leaf N content in 2006. These variables accounted for 25 and 27% of aphid variability in 2005 and 2006, respectively, suggesting that other sources of variability are also important. In addition, K content of soybean plants decreased with increasing prevalence of corn-soybean cropland in 2005, suggesting that landscapes that have a high intensification of agriculture (as indexed by increasing corn and soybean) are more likely to have higher aphid numbers. Soybean aphid natural enemies, 26 species of predators and parasitoids, was positively related to aphid abundance; however, enemy-to-aphid abundance ratios were inversely related to aphid density, suggesting that soybean aphids are able to escape control by resident natural enemies. Overall, soybean aphid abundance was most associated with soybean leaf chemistry and landscape heterogeneity. Agronomic options that can ameliorate K deficiency and maintaining heterogeneity in the landscape may reduce aphid risk.

  1. Direct determination of the nutrient profile in plant materials by femtosecond laser-induced breakdown spectroscopy.

    Science.gov (United States)

    de Carvalho, Gabriel Gustinelli Arantes; Moros, Javier; Santos, Dário; Krug, Francisco José; Laserna, J Javier

    2015-05-30

    Femtosecond laser-induced breakdown spectroscopy (fs-LIBS) has been used for the first time for quantitative determination of nutrients in plant materials from different crops. A highly heterogeneous population of 31 samples, previously analyzed by inductively coupled plasma optical emission spectroscopy, covering a wide range of matrices was interrogated. To tackle the analysis, laser-induced plasmas under argon atmosphere of pellets prepared from sieved cryogenically ground leaves were studied. Predictive functions based on univariate and multivariate modeling of optical emissions associated to macro- (Ca, Mg, and P) and micronutrients (Cu, Fe, Mn and Zn) were designed. Hierarchical cluster analysis was performed to select representative calibration (n(cal)=17) and validation (n(val)=14) datasets. The predictive performance of calibration functions over fs-LIBS data was compared with that attained on spectral information from nanosecond LIBS (ns-LIBS) operating at different wavelengths (1064 nm, 532 nm, and 266 nm). Findings established higher accuracy and less uncertainty on mass fractions quantification from fs-LIBS, whatever the modeling approach. Quality coefficients below 20% for the accuracy error on mass fractions' prediction in unknown samples, and residual predictive deviations in general above 5, were obtained. In contrast, only multivariate modeling satisfactorily handled the non-linear variations of emissions in ns-LIBS, leading to 2-fold decrease in the root mean square error of prediction (RMSEP) of Ca, Mg, P, Cu, Fe, Mn and Zn in comparison with the univariate approach. But still, an averaged quality coefficient about 35% and residual predictive deviations below 3 were found. Similar predictive capabilities were observed when changing the laser wavelength. Although predicted values by ns-LIBS multivariate modeling exhibit better agreement with reference mass fractions as compared to univariate functions, fs-LIBS conducts better quantification of

  2. Soil inoculation with symbiotic microorganisms promotes plant growth and nutrient transporter genes expression in durum wheat.

    Science.gov (United States)

    Saia, Sergio; Rappa, Vito; Ruisi, Paolo; Abenavoli, Maria Rosa; Sunseri, Francesco; Giambalvo, Dario; Frenda, Alfonso S; Martinelli, Federico

    2015-01-01

    In a field experiment conducted in a Mediterranean area of inner Sicily, durum wheat was inoculated with plant growth-promoting rhizobacteria (PGPR), with arbuscular mycorrhizal fungi (AMF), or with both to evaluate their effects on nutrient uptake, plant growth, and the expression of key transporter genes involved in nitrogen (N) and phosphorus (P) uptake. These biotic associations were studied under either low N availability (unfertilized plots) and supplying the soil with an easily mineralizable organic fertilizer. Regardless of N fertilization, at the tillering stage, inoculation with AMF alone or in combination with PGPR increased the aboveground biomass yield compared to the uninoculated control. Inoculation with PGPR enhanced the aboveground biomass yield compared to the control, but only when N fertilizer was added. At the heading stage, inoculation with all microorganisms increased the aboveground biomass and N. Inoculation with PGPR and AMF+PGPR resulted in significantly higher aboveground P compared to the control and inoculation with AMF only when organic N was applied. The role of microbe inoculation in N uptake was elucidated by the expression of nitrate transporter genes. NRT1.1, NRT2, and NAR2.2 were significantly upregulated by inoculation with AMF and AMF+PGPR in the absence of organic N. A significant down-regulation of the same genes was observed when organic N was added. The ammonium (NH4 (+)) transporter genes AMT1.2 showed an expression pattern similar to that of the NO3 (-) transporters. Finally, in the absence of organic N, the transcript abundance of P transporters Pht1 and PT2-1 was increased by inoculation with AMF+PGPR, and inoculation with AMF upregulated Pht2 compared to the uninoculated control. These results indicate the soil inoculation with AMF and PGPR (alone or in combination) as a valuable option for farmers to improve yield, nutrient uptake, and the sustainability of the agro-ecosystem.

  3. Screening of Less known Two Food Plants for Comparison of Nutrient Contents: Iranian and Indian Vegetables

    Directory of Open Access Journals (Sweden)

    Ali Aberoumand

    2011-10-01

    Full Text Available Background: Greater consumption of fruits and vegetables is associated with reduced risk of cardiovascular disease, stroke, and cancers. The most important nutrients present in plants are carbohydrates, such as the starch and free sugars, oils, proteins, minerals, ascorbic acid, and the antioxidant phenols. Plants are an essential component of the universe. Human beings have used those as medicine from the very beginning of time.Methods: The proximate composition and mineral constituents of Asparagus officinalis stem and Momordica dioica fruit were evaluated in order to scientific standard methods of Association for Official and Analytical Chemists (AOAC.Results: The stem contained ashes: 10.70% crude protein: 32.69%, crude lipid: 3.44%, crude fiber: 18.50%, and carbohydrates: 34.67%. Stem also have high energy value (384.27kcal/100g dry weight. Mineral ranges (mg/100g dry weight, DW were: K (10.94, Na (1.84, Ca (0.67, Fe (0.19, and Zn (2.60. The fruits contained ashes: 9.1%, crude protein: 5.44%, crude lipid: 3.25%, crude fiber: 22.9%, and carbohydrates: 59.31%. The fruits also have high energy value (288.25kcal/100g dry weight. Mineral ranges (mg/100g dry weight, DW were: K (4.63, Na (1.62, Ca (7.37, Fe (5.04, and Zn (3.83.Conclusion: Comparing proximate and minerals contents of the stem and the fruit, the results indicated that Asparagus officinalis stem could be a good supplement for some nutrients such as protein, lipid, potassium and zinc, fibre and carbohydrates while Momordica dioica fruit was good source of lipid, crude fiber, carbohydrates, iron and zinc.Functional Foods in Health and Disease 2011; 10:416-424

  4. Computer program for afterheat temperature distribution for mobile nuclear power plant

    Science.gov (United States)

    Parker, W. G.; Vanbibber, L. E.

    1972-01-01

    ESATA computer program was developed to analyze thermal safety aspects of post-impacted mobile nuclear power plants. Program is written in FORTRAN 4 and designed for IBM 7094/7044 direct coupled system.

  5. The plant nitrogen mobilization promoted by Colletotrichum lindemuthianum in Phaseolus leaves depends on fungus pathogenicity

    National Research Council Canada - National Science Library

    Virginie Tavernier; Sandrine Cadiou; Karine Pageau; Richard Laugé; Michèle Reisdorf-Cren; Thierry Langin; Céline Masclaux-Daubresse

    2007-01-01

    .... In order to study nitrogen recycling and mobilization in host plants during pathogen attack and invasion, the Colletotrichum lindemuthianum/Phaseolus vulgaris interaction was used as a model. C...

  6. Mobile robots for inspection and maintenance of piping in electrical power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jezequel, P.

    1987-01-01

    Mobile mechanical devices working with inspection and maintenance of pipes in electrical power plants might become useful to E.D.F. A specific field in robotics, with its proper know-how and complications, is being developed.

  7. PlaMoM: a comprehensive database compiles plant mobile macromolecules.

    Science.gov (United States)

    Guan, Daogang; Yan, Bin; Thieme, Christoph; Hua, Jingmin; Zhu, Hailong; Boheler, Kenneth R; Zhao, Zhongying; Kragler, Friedrich; Xia, Yiji; Zhang, Shoudong

    2017-01-04

    In plants, various phloem-mobile macromolecules including noncoding RNAs, mRNAs and proteins are suggested to act as important long-distance signals in regulating crucial physiological and morphological transition processes such as flowering, plant growth and stress responses. Given recent advances in high-throughput sequencing technologies, numerous mobile macromolecules have been identified in diverse plant species from different plant families. However, most of the identified mobile macromolecules are not annotated in current versions of species-specific databases and are only available as non-searchable datasheets. To facilitate study of the mobile signaling macromolecules, we compiled the PlaMoM (Plant Mobile Macromolecules) database, a resource that provides convenient and interactive search tools allowing users to retrieve, to analyze and also to predict mobile RNAs/proteins. Each entry in the PlaMoM contains detailed information such as nucleotide/amino acid sequences, ortholog partners, related experiments, gene functions and literature. For the model plant Arabidopsis thaliana, protein-protein interactions of mobile transcripts are presented as interactive molecular networks. Furthermore, PlaMoM provides a built-in tool to identify potential RNA mobility signals such as tRNA-like structures. The current version of PlaMoM compiles a total of 17 991 mobile macromolecules from 14 plant species/ecotypes from published data and literature. PlaMoM is available at http://www.systembioinfo.org/plamom/. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  8. Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

    Science.gov (United States)

    Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

    2015-01-01

    Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  9. Responses of nutrients and mobile carbohydrates in Quercus variabilis seedlings to environmental variations using in situ and ex situ experiments.

    Directory of Open Access Journals (Sweden)

    Jing-Pin Lei

    Full Text Available Forest tree species distributed across a wide range of geographical areas are subjected to differential climatic and edaphic conditions and long-term selection, leading to genotypes with morphological and physiological adaptation to the local environment. To test the ability of species to cope with changing environmental conditions, we studied the ecophysiological features of Quercus variabilis using seedlings grown in geographically widely isolated populations (Exp. I, in situ and in a common garden (Exp. II, ex situ using seedlings originating from those populations. We found that Q. variabilis plants grown in different locations along a south-north gradient had different levels of nutrients (N, P, K and carbon-physiological performance (photosynthesis, non-structural carbohydrates, such as soluble sugars and starch, and that these physiological differences were not correlated with local soil properties. These geographic variations of plant physiology disappeared when plants from different locations were grown in the same environment. Our results indicate that the physiological performance of Q. variabilis plants is mainly determined by the climatic variations across latitude rather than by their soils or by genetic differentiation. The adaptive ability of Q. variabilis found in the present study suggests that this species has the potential to cope, at least to some extent, with changing environmental conditions.

  10. Responses of nutrients and mobile carbohydrates in Quercus variabilis seedlings to environmental variations using in situ and ex situ experiments.

    Science.gov (United States)

    Lei, Jing-Pin; Xiao, Wenfa; Liu, Jian-Feng; Xiong, Dingpeng; Wang, Pengcheng; Pan, Lei; Jiang, Yong; Li, Mai-He

    2013-01-01

    Forest tree species distributed across a wide range of geographical areas are subjected to differential climatic and edaphic conditions and long-term selection, leading to genotypes with morphological and physiological adaptation to the local environment. To test the ability of species to cope with changing environmental conditions, we studied the ecophysiological features of Quercus variabilis using seedlings grown in geographically widely isolated populations (Exp. I, in situ) and in a common garden (Exp. II, ex situ) using seedlings originating from those populations. We found that Q. variabilis plants grown in different locations along a south-north gradient had different levels of nutrients (N, P, K) and carbon-physiological performance (photosynthesis, non-structural carbohydrates, such as soluble sugars and starch), and that these physiological differences were not correlated with local soil properties. These geographic variations of plant physiology disappeared when plants from different locations were grown in the same environment. Our results indicate that the physiological performance of Q. variabilis plants is mainly determined by the climatic variations across latitude rather than by their soils or by genetic differentiation. The adaptive ability of Q. variabilis found in the present study suggests that this species has the potential to cope, at least to some extent, with changing environmental conditions.

  11. Plant Community and Nutrient Status of the Soils of Schirmacher Oasis, East Antarctica

    Institute of Scientific and Technical Information of China (English)

    Shiv Mohan Singh; Jagdev Sharma; Rasik Ravindra; Purnima Singh

    2008-01-01

    Investigations on plant community and micronutrient status of Schirmacher Oasis,East Antarctica have been presented in this paper.The dominant plant communities include moss and lichen.The frequency of species occurrence and changes in species composition at different location varied.Thirty four soil samples were analyzed for chemical properties of the soils of Schirmacher Oasis and Nunatak,East Antarctica.The most common plant species growing throughout the areas of Schirmacher Oasis and Nunataks are: Candelariella flava (lichen) and Bryum pseudotriquetrum (moss).Large variations were observed among different soil samples in all the nutrients and other measured soil chemical parameters.The soils are characterized by acidic pH ranging from 4.42-6.80.The mean organic carbon content was 0.62 and ranged from 0.06-1.29%.The electrical conductivity in 1:2 soil water ratio ranged from 0.06-1.29.The average content of macronutrient cation,which are ammonium acetate extractable was in the order of Ca>K>Na>Mg.The average content of DTPA extractable micronutrient cations was in the order of Fe>Mn>Cu>Zn.Thirty one out of 34 samples contained less than 0.80 ppm DTPA extractable Zn.Correlation studies revealed that content of macronutrient cationssignificantly and positively correlated to that of chlorides.Electrical conductivity exhibited significant and positive relationship with pH,K,Ca,Mg,Na and chloride content.Sodium (r=0.876 **) exhibited highest correlation followed by K (r=0.831 **) with chloride content.The correlation coefficient for chlorides was higher with electrical conductivity (r=0.732 **) than pH (r=0.513 **).Organic carbon content of the soil was positively correlated with Fe (r=0.442 *).The nutrient status did not appear to be a limiting factor in growth of plants.Lichen and moss community structure and composition inthe study area were not related with fertility status of soil.Terrestrial mosses are most abundant and luxuriant along the soil habitats

  12. Agricola use of compost and vermicomposts of urban wastes: supplying of nutrients to soil and plant; Uso agricola de compost y vermicompost de basuras urbanas: capacidad de cesion de nutrientes al suelo y la plant

    Energy Technology Data Exchange (ETDEWEB)

    Nogales, R.; Elvira, C.; Benitez, E.; Gallardo-Lara, F. [Dpto. Agroecoliga y Proteccion Vegetal, Estacion Experimental del Zaidin, CSIC (Spain)

    1996-06-01

    Compost and vermicomposts from town refuse can be considered as a valuable resource for supplying nitrogen, potassium and some micro nutrients to soils and plants. Application of these mature organic materials increase crop yield, although they are less efficient than mineral fertilizers in order to obtain inmediate crops. (Author) 79 refs.

  13. Multiple soil nutrient competition between plants, microbes, and mineral surfaces: model development, parameterization, and example applications in several tropical forests

    Science.gov (United States)

    Zhu, Q.; Riley, W. J.; Tang, J.; Koven, C. D.

    2016-01-01

    Soil is a complex system where biotic (e.g., plant roots, micro-organisms) and abiotic (e.g., mineral surfaces) consumers compete for resources necessary for life (e.g., nitrogen, phosphorus). This competition is ecologically significant, since it regulates the dynamics of soil nutrients and controls aboveground plant productivity. Here we develop, calibrate and test a nutrient competition model that accounts for multiple soil nutrients interacting with multiple biotic and abiotic consumers. As applied here for tropical forests, the Nutrient COMpetition model (N-COM) includes three primary soil nutrients (NH4+, NO3- and POx; representing the sum of PO43-, HPO42- and H2PO4-) and five potential competitors (plant roots, decomposing microbes, nitrifiers, denitrifiers and mineral surfaces). The competition is formulated with a quasi-steady-state chemical equilibrium approximation to account for substrate (multiple substrates share one consumer) and consumer (multiple consumers compete for one substrate) effects. N-COM successfully reproduced observed soil heterotrophic respiration, N2O emissions, free phosphorus, sorbed phosphorus and NH4+ pools at a tropical forest site (Tapajos). The overall model uncertainty was moderately well constrained. Our sensitivity analysis revealed that soil nutrient competition was primarily regulated by consumer-substrate affinity rather than environmental factors such as soil temperature or soil moisture. Our results also imply that under strong nutrient limitation, relative competitiveness depends strongly on the competitor functional traits (affinity and nutrient carrier enzyme abundance). We then applied the N-COM model to analyze field nitrogen and phosphorus perturbation experiments in two tropical forest sites (in Hawaii and Puerto Rico) not used in model development or calibration. Under soil inorganic nitrogen and phosphorus elevated conditions, the model accurately replicated the experimentally observed competition among

  14. Effects of High Ammonium Concentration on Growth and Nutrient Uptake of Lettuce Plants with Solution Culture

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A nutrition solution experiment was conducted over two months to investigate the response of vegetable crops to high concentrations of ammonium, using lettuce (Lactuca sativa L. cv. Angustana Irish) as a test crop. Ammonium concentrations were designed in 5 levels, ranging from 12 mmol N L-1 to 22 mmol N L-1 and local tap water was used as water source. At the first culture stage (0-9 days), lettuce plants maintained normal growth while the lettuce roots were increasingly impaired. During the subsequent three stages the root structure was greatly damaged, and roots became brown or black through continuous supply of high concentration of ammonium. However, there was no obvious reduction of the aboveground biomass of the plants in the high ammonium treatments compared to those supplied with nitrate alone. In contrast to results obtained in another experiment from us with distilled water, the detrimental effect of high ammonium concentration on lettuce growth was greatly alleviated. Based on the results, it was postulated that the small amount of nitrate and the higher amount of bicarbonate existed in the tap water might mitigate the adverse effects of high ammonium N. The higher bicarbonate content in water and soil has usually been regarded as a major constraint factor limiting plant growth in calcareous soil areas. However, the reaction of bicarbonate to ammonium might produce positively interactive effect on reduction of both damages. The lettuce plants grown in ammonium solutions took up less P, K, Fe, Mn and Cu and more Ca than those grown in the nitrate nutrient solution. In conclusion, the results indicated that the N form imposed an obvious influence on absorption of cations and anions. Supplying ammonium-N stimulated transport of Ca, Mg and Mn to shoots of lettuce.

  15. Modifications of Morphometrical and Physiological Parameters of Pepper Plants Grown on Artificial Nutrient Medium for Experiments in Spaceflight

    Science.gov (United States)

    Nechitailo, Galina S.

    2016-07-01

    MODIFICATIONS OF MORPHOMETRICAL AND PHYSIOLOGICAL PARAMETERS OF PEPPER PLANTS GROWN ON ARTIFICIAL NUTRIENT MEDIUM FOR EXPERIMENTS IN SPACEFLIGHT Lui Min*, Zhao Hui*, Chen Yu*, Lu Jinying*, Li Huasheng*, Sun Qiao*, Nechitajlo G.S.**, Glushchenko N.N.*** *Shenzhou Space Biotechnology Group, China Academy of Space Technology (CAST), **Emanuel Institute of Biochemical Physics of Russian Academy of Sciences (IBCP RAS) mail: spacemal@mail.ru ***V.L. Talrose Institute for Energy Problems of Chemical Physics of Russian Academy of Science (INEPCP RAS) mail: nnglu@ mail.ru In circumstances of space flights, long residence of the staff at space stations and space settlements an optimal engineering system of the life-support allowing to solve a number of technical and psychological problems for successful work and a life of cosmonauts, researchers, etc. is important and prime. In this respect it is necessary to consider growing plants on board of spacecraft as one of the units in a life-support system. It is feasible due to modern development of biotechnologies in growing plants allowing us to receive materials with new improved properties. Thus, a composition and ratio of components of nutrient medium can considerably influence on plants properties. We have developed the nutrient medium in which essential metals such as iron, zinc, copper were added in an electroneutral state in the form of nanoparticles instead of sulfates or other salts of the same metals. Such replacement is appropriate through unique nanoparticles properties: metal nanoparticles are less toxic than their corresponding ionic forms; nanoparticles produce a prolonged effect, serving as a depot for elements in an organism; nanoparticles introduced in biotic doses stimulate the metabolic processes of the organism; nanoparticles effect is multifunctional. Pepper strain LJ-king was used for growing on a nutrient medium with ferrous, zinc, copper nanoparticles in different concentrations. Pepper plants grown on

  16. An invasive clonal plant benefits from clonal integration more than a co-occurring native plant in nutrient-patchy and competitive environments.

    Science.gov (United States)

    You, Wenhua; Fan, Shufeng; Yu, Dan; Xie, Dong; Liu, Chunhua

    2014-01-01

    Many notorious invasive plants are clonal, however, little is known about the different roles of clonal integration effects between invasive and native plants. Here, we hypothesize that clonal integration affect growth, photosynthetic performance, biomass allocation and thus competitive ability of invasive and native clonal plants, and invasive clonal plants benefit from clonal integration more than co-occurring native plants in heterogeneous habitats. To test these hypotheses, two stoloniferous clonal plants, Alternanthera philoxeroides (invasive), Jussiaea repens (native) were studied in China. The apical parts of both species were grown either with or without neighboring vegetation and the basal parts without competitors were in nutrient- rich or -poor habitats, with stolon connections were either severed or kept intact. Competition significantly reduced growth and photosynthetic performance of the apical ramets in both species, but not the biomass of neighboring vegetation. Without competition, clonal integration greatly improved the growth and photosynthetic performance of both species, especially when the basal parts were in nutrient-rich habitats. When grown with neighboring vegetation, growth of J. repens and photosynthetic performance of both species were significantly enhanced by clonal integration with the basal parts in both nutrient-rich and -poor habitats, while growth and relative neighbor effect (RNE) of A. philoxeroides were greatly improved by clonal integration only when the basal parts were in nutrient-rich habitats. Moreover, clonal integration increased A. philoxeroides's biomass allocation to roots without competition, but decreased it with competition, especially when the basal ramets were in nutrient-rich sections. Effects of clonal integration on biomass allocation of J. repens was similar to that of A. philoxeroides but with less significance. These results supported our hypothesis that invasive clonal plants A. philoxeroides benefits

  17. The influence of arbuscular mycorrhizae on root precision nutrient foraging of two pioneer plant species during early reclamation

    Science.gov (United States)

    Boldt-Burisch, Katja; Naeth, M. Anne

    2017-04-01

    On many post mining sites in the Lusatian Mining District (East Germany) soil heterogeneity consists of sandy soil with embedded clay-silt fragments. Those clays silt fragments might act as nutrient hotspots. Arbuscular mycorrhizal fungi in an infertile ecosystem could enhance a plant's ability to selectively forage for those nutrients and thus to improve plants nutrient supply. In our study we investigated whether silt-clay fragments within a sandy soil matrix induced preferential root growth of Lotus corniculatus and Calamagrostis epigeios, whether arbuscular mycorrhizae influenced root foraging patterns, and to what extent selective rooting in clay silt fragments influenced plant growth were addressed in this research. Soil types were sterile and non-sterile sandy soil and clay-silt fragments. Treatments were with and without arbuscular mycorrhizae, with and without soil solution, and soil solution and mycorrhizal inoculum combined. Root biomass, root density and intraradical fungal alkaline phosphatase activity and frequency were determined in fragments relative to sandy soil. Furthermore, temporal relationship of number of roots in fragments and plant height was assessed. Lotus corniculatus showed strong selective rooting into fragments especially with those plants treated with commercial cultivated arbuscular mycorrhizae; Calamagrostis epigeios did not. Without arbuscular mycorrhizae, L. corniculatus growth was significantly reduced and selective rooting did not occur. Selective rooting induced significant growth spurts of L. corniculatus. Roots in fragments had higher fungal alkaline phosphatase activity suggesting that mycorrhizal efficiency and related plants phosphorus supply is enhanced in roots in fragments. The application of cultivated arbuscular mycorrhizal fungi significantly and quickly influenced root foraging patterns, especially those of L. corniculatus, suggesting mycorrhizae may also enhance the ability of other plants to selectively forage

  18. Nutrient allocation strategies of woody plants: an approach from the scaling of nitrogen and phosphorus between twig stems and leaves

    OpenAIRE

    Zhengbing Yan; Peng Li; Yahan Chen; Wenxuan Han; Jingyun Fang

    2016-01-01

    Allocation of limited nutrients, such as nitrogen (N) and phosphorus (P), among plant organs reflects the influences of evolutionary and ecological processes on functional traits of plants, and thus is related to functional groups and environmental conditions. In this study, we tested this hypothesis by exploring the stoichiometric scaling of N and P concentrations between twig stems and leaves of 335 woody species from 12 forest sites across eastern China. Scaling exponents of twig stem N (o...

  19. Weed management, training, and irrigation practices for organic production of trailing blackberry: II. Soil and plant nutrient concentrations

    Science.gov (United States)

    Organic production of blackberries is increasing, but there is relatively little known about how production practices affect plant and soil nutrient status. The impact of cultivar (‘Black Diamond’ and ‘Marion’), weed management (weed mat, hand weeding, and no weeding), primocane training time (Augus...

  20. Advanced oxidation to eliminate growth inhibition and to degrade plant protection products in a recirculating nutrient solution in Rose cultivation

    NARCIS (Netherlands)

    Os, van E.A.; Maas, van der A.A.; Meijer, R.J.M.; Khodabaks, M.R.; Blok, C.; Enthoven, N.L.M.

    2012-01-01

    The EU Water Framework Directive demands a sound ecological and chemical basis for ground and surface waters. This has motivated the Dutch greenhouse industry to seek more sustainable water management procedures which will enable a zero-emission of nutrients and plant protection products (PPP) in th

  1. Export of nutrients in plants jambu under different fertilizationExportação de nutrientes em plantas de jambu, sob diferentes adubações

    Directory of Open Access Journals (Sweden)

    Luciana da Silva Borges

    2013-03-01

    Full Text Available The jambu is a broad vegetable consumption in Northern Brazil, especially in Pará, known by the jambu and other common names is native to the Amazon region has been used and cultivated for culinary and also recently in natural medicines by their chemical properties, attributed to the spilanthol compound. Knowing the amount of nutrient uptake in plants, especially at the taken, it is important to evaluate the removal of nutrients necessary for economic fertilizer recommendations. So the goal of this project was to determine the accumulation of nutrients in plants of jambu (leaf and inflorescence under different fertilizations. The experiment was conducted at São Manuel Experimental Farm UNESP. The statistical was arranged in the randomized block design, in a 2 x 6 factorial scheme, two sources of fertilizers (organic and mineral and six doses of nitrogen, with four replications. We evaluated the macronutrients of accumulation N, P, K, Ca, Mg, S and micronutrients of accumulation B, Cu, Fe and Zn in leaves and inflorescence. The plants responded more jambu nutrients of translocation phosphorus (P, magnesium (Mg, sulfhur (S, boron (B, copper (Cu and iron (Fe in the inflorescences and phosphorus (P, calcium (Ca, manganese (Mg, sulfur (S, boron (B, copper (Cu and iron (Fe in leaves to organic fertilization demonstrating the effectiveness of using this source of fertilizer nutrients indicating that this was a defining characteristic in response to the accumulation of nutrients in the leaves and inflorescences jambu. Plants jambu are more responsive to fertilizer for the mineral of translocation nitrogen (N and manganese (Mn for both the sheet and for the inflorescences of plants jambu. O jambu é uma hortaliça de largo consumo na região Norte do Brasil, conhecida por diferentes nomes populares, como agrião do Pará, erva maluca, botão de ouro, é uma espécie nativa da Amazônia, bastante utilizada na culinária regional e também em

  2. Influence of Nitrogen Sources and Plant Growth-Promoting Rhizobacteria Inoculation on Growth, Crude Fiber and Nutrient Uptake in Squash (Cucurbita moschata Duchesne ex Poir. Plants

    Directory of Open Access Journals (Sweden)

    Alice I. TCHIAZE

    2016-06-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR, B have immense potential application in sustainable agriculture as ecofriendly biofertilizers and biopesticides. In this study, the effects of three nitrogen (N sources (NO3-, NH4+ and NO3NH4 and PGPR on growth, crude fiber and nutrient uptake were investigated in squash plants. Some growth parameters [root dry weight (RDW, shoot dry weight (SDW, total plant dry weight (PDW, number of leaves (NL, shoot length (SL, stem diameter (SD and number of ramifications (NR], crude fiber (cellulose content and nutrient uptake (N, P, K, Ca, Mg, Na, Fe, Cu, Mn and Zn were determined. Application of NO3-,NH4+ or NO3NH4 singly or in combination with PGPR inoculation led to a significant increase in RDW, SDW, PDW, NL, SL, SD and NR. Na, Cu and Zn contents, on the contrary, decreased in inoculated treated plants while no significant differences were recorded in cellulose contents (CE of leaves except in plants fed with NO3-. The leaf CE content ranged from 12.58 to 13.67%. The plants supplied with NO3+B, NH4+B and NO3NH4+B showed significantly higher plant biomass and accumulation of N, P, K and Mn concentrations in leaves compared to all other treatments. These results suggest that specific combinations of PGPR with NO3-, NH4+ or NO3NH4 fertilizers can be considered as efficient alternative biofertilizers to improve significantly the squash growth and nutrient uptake.

  3. Rhizofiltration of lead using an aromatic medicinal plant Plectranthus amboinicus cultured in a hydroponic nutrient film technique (NFT) system.

    Science.gov (United States)

    Ignatius, A; Arunbabu, V; Neethu, J; Ramasamy, E V

    2014-11-01

    Heavy metal contamination of water bodies and groundwater is a major concern of the modern world. Rhizofiltration--the use of plant root system to remove/extract pollutants from wastewater--has proven advantages over conventional methods of treatment. However, commercialization of this in situ remediation technology requires a better understanding of plant-metal interactions especially on the ability of different plant species to accumulate metals at different parts of the plant system which is critical for the successful remediation of contaminated medium. Many aquatic and terrestrial plants have been reported to accumulate heavy metals when grown hydroponically. Therefore, a batch experiment with different concentrations of lead and a nutrient film technique (NFT) experiment with recycling of wastewater were employed in this study in order to investigate the rhizofiltration of lead-containing wastewater using Plectranthus amboinicus, an aromatic medicinal plant. Results show that P. amboinicus is tolerant to a wide range of lead concentrations and nutrient deficiency. The plant accumulates considerable amount of lead, particularly in the roots, and translocation to the stem and leaf was limited, indicating that the use of leaves/above-ground parts of the plant for medicinal purposes is not hindered by its ability to remove lead from the soil or water. The study also suggests that the plant can be considered for the clean-up of lead-contaminated wastewater in combination with safe biomass disposal alternatives.

  4. Soil management with respect to nitrogen mobilization and nutrient supply of grapevines on loess soil

    Science.gov (United States)

    Mehofer, Martin

    2017-04-01

    The effects of different methods of soil management on the nutrient supply and the vine quality of organically grown `Grüner Veltliner` grapevines (Guyot double) were investigated in the winegrowing region Wagram of Lower Austria (municipality: Großriedenthal). Under permanent green cover the mineral nitrogen content in the soil was significantly lower than under green cover only in each second row. Regarding the nitrogen demand of the vine the best results of the mineral nitrogen content in soil were found by loosening up the soil by the end of April and breaking it open two weeks later. Permanent green cover inhibited shoot length development and the total acidity of the must was lower. The content of yeast assimilable nitrogen and the yield were reduced, but must density as well as potassium and ash contents of the wine were slightly higher. There were no differences in the vinification of the grapes of different origins. Significant differences in the sensory evaluation could not be related to different methods of soil cultivation.

  5. Increasing Plant Based Foods or Dairy Foods Differentially Affects Nutrient Intakes: Dietary Scenarios Using NHANES 2007-2010.

    Science.gov (United States)

    Cifelli, Christopher J; Houchins, Jenny A; Demmer, Elieke; Fulgoni, Victor L

    2016-07-11

    Diets rich in plant foods and lower in animal-based products have garnered increased attention among researchers, dietitians and health professionals in recent years for their potential to, not only improve health, but also to lessen the environmental impact. However, the potential effects of increasing plant-based foods at the expense of animal-based foods on macro- and micronutrient nutrient adequacy in the U.S. diet is unknown. In addition, dairy foods are consistently under consumed, thus the impact of increased dairy on nutrient adequacy is important to measure. Accordingly, the objective of this study was to use national survey data to model three different dietary scenarios to assess the effects of increasing plant-based foods or dairy foods on macronutrient intake and nutrient adequacy. Data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 for persons two years and older (n = 17,387) were used in all the analyses. Comparisons were made of usual intake of macronutrients and shortfall nutrients of three dietary scenarios that increased intakes by 100%: (i) plant-based foods; (ii) protein-rich plant-based foods (i.e., legumes, nuts, seeds, soy); and (iii) milk, cheese and yogurt. Scenarios (i) and (ii) had commensurate reductions in animal product intake. In both children (2-18 years) and adults (≥19 years), the percent not meeting the Estimated Average Requirement (EAR) decreased for vitamin C, magnesium, vitamin E, folate and iron when plant-based foods were increased. However the percent not meeting the EAR increased for calcium, protein, vitamin A, and vitamin D in this scenario. Doubling protein-rich plant-based foods had no effect on nutrient intake because they were consumed in very low quantities in the baseline diet. The dairy model reduced the percent not meeting the EAR for calcium, vitamin A, vitamin D, magnesium, and protein, while sodium and saturated fat levels increased. Our modeling shows that increasing plant

  6. Increasing Plant Based Foods or Dairy Foods Differentially Affects Nutrient Intakes: Dietary Scenarios Using NHANES 2007–2010

    Directory of Open Access Journals (Sweden)

    Christopher J. Cifelli

    2016-07-01

    Full Text Available Diets rich in plant foods and lower in animal-based products have garnered increased attention among researchers, dietitians and health professionals in recent years for their potential to, not only improve health, but also to lessen the environmental impact. However, the potential effects of increasing plant-based foods at the expense of animal-based foods on macro- and micronutrient nutrient adequacy in the U.S. diet is unknown. In addition, dairy foods are consistently under consumed, thus the impact of increased dairy on nutrient adequacy is important to measure. Accordingly, the objective of this study was to use national survey data to model three different dietary scenarios to assess the effects of increasing plant-based foods or dairy foods on macronutrient intake and nutrient adequacy. Data from the National Health and Nutrition Examination Survey (NHANES 2007–2010 for persons two years and older (n = 17,387 were used in all the analyses. Comparisons were made of usual intake of macronutrients and shortfall nutrients of three dietary scenarios that increased intakes by 100%: (i plant-based foods; (ii protein-rich plant-based foods (i.e., legumes, nuts, seeds, soy; and (iii milk, cheese and yogurt. Scenarios (i and (ii had commensurate reductions in animal product intake. In both children (2–18 years and adults (≥19 years, the percent not meeting the Estimated Average Requirement (EAR decreased for vitamin C, magnesium, vitamin E, folate and iron when plant-based foods were increased. However the percent not meeting the EAR increased for calcium, protein, vitamin A, and vitamin D in this scenario. Doubling protein-rich plant-based foods had no effect on nutrient intake because they were consumed in very low quantities in the baseline diet. The dairy model reduced the percent not meeting the EAR for calcium, vitamin A, vitamin D, magnesium, and protein, while sodium and saturated fat levels increased. Our modeling shows that

  7. Effect of nitrogen rate and irrigation frequency on plant growth and nutrient uptake of container-grown Hydrangea macrophylla ‘Merritt’s Supreme’

    Science.gov (United States)

    The production of high quality container-grown nursery plants requires adequate but not excessive nutrients and water during production. Given the knowledge that N is the most important nutrient element for plant growth and that it is often the limiting factor, nursery growers tend to apply high lev...

  8. Advanced nutrient root feeding system for conveyer-type cylindrical plant growth facilities developed for microgravity

    Science.gov (United States)

    Berkovich, Yuliy A.; Smolyanina, Svetlana O.; Krivobok, Anna; Krivobok, Nikolay

    A new brand of cylindrical conveyer-type space plant growth facilities (PGF) has been created to improve of cosmonauts’ diet in the microgravity conditions. Up to date several ground prototypes of the space PGF have been made and tested: “Phytocycle”, “Vitacycle”, “Phytocycle-LED”, “Phytoconveyer”; now the space PGF “Vitacycle-T” for the Russian segment of the ISS is under developing. In the PGFs the ion-exchange salt-saturated fibrous artificial soil (AS) is used as a root medium. We have proposed the system for enrichment of irrigation water by nutrients to decrease of the AS store required for PGF working during the long space mission. The system includes root modules filled in fibrous ion-exchange AS, the enrichment column with crumble salt-saturation ion-exchange resin and the cassette with slow releasing fertilizer (SRF). Both substrates (ion-exchange resin and SRF) are necessary because of the SRF contains mostly N, P and K but another three essential elements S, Ca, Mg are provided by the ion-exchange resin. In the system water goes throw the enrichment column with ion-exchange resin fertilizing by the nutrients and comes into the mixer cell fertilize equipped with the electrical conductivity sensor. When the signal of the conductivity sensor is coming to the controller it turns on the pump directed the water flow throw the cassette with SRF until the electric conductivity of the solution in the mixer cell will reach the setpoint. The nutrient root feeding system was tested during 88 days when Chinese cabbage grew in PGF “Phytocycle-LED”. The crop has been continuously illuminated by red and blue LEDs in the PPF ratio 7 to 1; an integral PPF level has been (240 ± 10) µmol/(m2×s). There was no renewal of the used fibrous AS during the experiment. The PGF total electric power consumption was of 0,45 kW. The average fresh biomass productivity of the PGF during steady state working mode was equal 135×g/day per m2 of the illuminated

  9. Increasing nitrogen rates in rice and its effect on plant nutrient composition and nitrogen apparent recovery

    Directory of Open Access Journals (Sweden)

    Juan Hirzel

    2013-12-01

    Full Text Available Rice (Oryza sativa L. is one of the essential foods of the human diet; advances in agronomic crop management can improve productivity and profitability as well as reduce adverse environmental impacts. Nitrogen rates in Chile are generally based on crop yield without considering other agronomic factors. The objective of this experiment was to determine the effect of increasing N rates on plant nutrient composition and N apparent recovery in rice cultivated in five different locations in Chile. The five sites located in central Chile belong to one of the following soil orders: Inceptisol, Alfisol, and Vertisol; they were cropped in field conditions with 'Zafiro-INIA' rice fertilized with 0, 80, and 160 kg N ha-1. Whole-plant total DM, macronutrient composition, and N apparent recovery efficiency (NARE were determined at grain harvest. Results indicate that all evaluated parameters, with the exception of K concentration, were affected by the soil used. Nitrogen rates only affected total DM production and P, K, and Mg concentrations in plants. Phosphorus and K response decreased when N was added to some soils, which is associated with its chemical properties. Magnesium concentration exhibited an erratic effect, but it was not affected by the N rate in most soils. Nitrogen apparent recovery efficiency was not affected by the N rate and accounted for approximately 49% and 41% for 80 and 160 kg N ha-1, respectively. Macronutrient composition was 5.1-7.7 g N, 1.3-1.8 g P, 5.4-10.8 g K, 1.68-2.57 g Ca, and 0.81-1.45 g Mg kg-1 of total DM.

  10. Mobile central heating plant ensures the supply during the power-plant modernization. Planning-safe reconstruction; Mobile Heizzentrale sichert Versorgung waehrend Kraftwerksmodernisierung. Planungssicherer Umbau

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, Petra [Mobiheat GmbH, Friedberg (Germany). Presse- und Oeffentlichkeitsarbeit

    2012-09-15

    During the comprehensive energetic retrofitting of district heating plants in the spa resort of Badenweiler (Federal Republic of Germany) a mobile 2-MW heating plant from Mobilheat (Ebersberg, Federal Republic of Germany) was used for the heat supply. Thus, the installation of environmental friendly energy supply based on cogeneration plants could be implemented with planning security. This particularly was important because, among other things, the traditional spa resort, the Kurhaus as well as hotels and private customers depend on the heat supply system. These buildings have be supplied with thermal water also in the summer.

  11. Nutrient use preferences among soil Streptomyces suggest greater resource competition in monoculture than polyculture plant communities

    Science.gov (United States)

    Nutrient use overlap among sympatric Streptomyces populations is correlated with pathogen inhibitory capacity, yet there is little information on either the factors that influence nutrient use overlap among coexisting populations or the diversity of nutrient use among soil Streptomyces. We examined ...

  12. Changes in plant biomass and nutrient removal over 3 years in a constructed wetland in Cairns, Australia.

    Science.gov (United States)

    Greenway, M; Woolley, A

    2001-01-01

    The surface flow wetland in Cairns, Australia consists of 3 linear channels each 65 m long. Channels 1 and 2 are 5 m wide and Channel 3 is 15 m wide. The wetland was constructed in 1994 and band planted with emergent macrophyte species and alternating open water sections. The wetland was monitored for plant growth and nutrient removal until 1997. During that period HRT was 16 days in Channel 1 and 10 days in Channels 2 and 3; mass loading rates were 2.4 kg Total N and 2.0 kg Total P ha(-1) d(-1) in Channel 1 and 3.7 kg TN and 3.3 kg TP ha(-1) d(-1) in Channels 2 and 3. The aim of this work was to determine the proportion of nutrient removal that could be attributed to direct uptake by macrophytes and incorporated into plant biomass. Over the 3 year monitoring period reduction in total mass of nutrients was: Channel 1: 26% P, 85% N; Channel 2: 28% P, 87% N; Channel 3: 21% P, 81% N. Percentage reduction of FRP (Filterable Reactive Phosphorus) was similar to TP; NOx removal was 97-98%. Mass removal rates for TN and TP were higher in Channels 2 and 3 despite greater nutrient loading rates and shorter detention times. Total FRP removal was 23 kg P in Channel 1, 33 kg P in Channel 2 and 70 kg P in Channel 3 of which plant biomass accounted for 65%, 44% and 47% respectively. Total nitrogen removal was 92 kg in Channel 1,154 kg in Channel 2 and 386 kg in Channel 3 of which plant biomass accounted for 47%, 27% and 27% respectively. Thus, in this tropical surface flow wetland supporting a mixture of emergent macrophytes and floating duckweed, vegetation is an important mechanism for direct nutrient removal.

  13. Mobility of nutrients and trace metals during weathering in the late Archean

    Science.gov (United States)

    Hao, Jihua; Sverjensky, Dimitri A.; Hazen, Robert M.

    2017-08-01

    The evolution of the geosphere and biosphere depends on the availability of bio-essential nutrients and trace metals. Consequently, the chemical and isotopic variability of trace elements in the sedimentary record have been widely used to infer the existence of early life and fluctuations in the near-surface environment on the early Earth, particularly fluctuations in the redox state of the atmosphere. In this study, we applied late Archean weathering models (Hao et al., 2017), developed to estimate the behavior of major elements and the composition of late Archean world average river water, to explore the behavior of nutrient and trace metals and their potential for riverine transport. We focused on P, Mn, Cr, and Cu during the weathering of olivine basalt. In our standard late Archean weathering model (pCO2,g = 10-1.5 bars, pH2,g = 10-5.0 bars), crustal apatite was totally dissolved by the acidic rainwater during weathering. Our model quantitatively links the pCO2,g of the atmosphere to phosphate levels transported by rivers. The development of late Archean river water (pH = 6.4) resulted in riverine phosphate of at least 1.7 μmolar, much higher than at the present-day. At the end of the early Proterozoic snowball Earth event when pCO2,g could be 0.01-0.10 bars, river water may have transported up to 70 μmolar phosphate, depending on the availability of apatite, thereby stimulating high levels of oxygenic photosynthesis in the marine environment. Crustal levels of Mn in olivine dissolved completely during weathering, except at large extents of weathering where Mn was stored as a component of a secondary carbonate mineral. The corresponding Mn content of river water, about 1.2 μmolar, is higher than in modern river water. Whiffs of 10-5 mole O2 gas or HNO3 kg-1 H2O resulted in the formation of pyrolusite (MnO2) and abundant hematite and simultaneous dramatic decreases in the concentration of Mn(II) in the river water. Chromite dissolution resulted in negligible

  14. Soil Nutrient Availability, Plant Nutrient Uptake, and Wild Blueberry (Vaccinium angustifolium Ait. Yield in Response to N-Viro Biosolids and Irrigation Applications

    Directory of Open Access Journals (Sweden)

    Aitazaz A. Farooque

    2012-01-01

    Full Text Available We compared the impact of surface broadcasted N-Viro biosolids and inorganic fertilizer (16.5% Ammonium sulphate, 34.5% Diammonium phosphate, 4.5% Potash, and 44.5% s and/or clay filler applications on soil properties and nutrients, leaf nutrient concentration, and the fruit yield of lowbush blueberry under irrigated and nonirrigated conditions during 2008-2009 at Debert, NS, Canada. Application rates of N-Viro biosolids were more than double of inorganic fertilizer applied at a recommended N rate of 32 kg ha−1. The experimental treatments NI: N-Viro with irrigation, FI: inorganic fertilizer with irrigation, N: N-Viro without irrigation, and F: inorganic fertilizer without irrigation (control were replicated four times under a randomized complete block design. The NI treatment had the highest OM (6.68% followed by FI (6.32%, N (6.18%, and F (4.43% treatments during the year 2008. Similar trends were observed during 2009 with the highest soil OM values (5.50% for NI treatment. Supplemental irrigation resulted in a 21% increase in the ripe fruit yield. Nonsignificant effect of fertilizer treatments on most of the nutrient concentrations in soil and plant leaves, and on ripe fruits yield reflects that the performance of N-Viro was comparable with that of the inorganic fertilizer used in this study.

  15. Autophagy provides nutrients for nonassimilating fungal structures and is necessary for plant colonization but not for infection in the necrotrophic plant pathogen Fusarium graminearum

    DEFF Research Database (Denmark)

    Josefsen, Lone; Droce, Aida; Søndergaard, Teis

    2012-01-01

    The role of autophagy in necrotrophic fungal physiology and infection biology is poorly understood. We have studied autophagy in the necrotrophic plant pathogen Fusarium graminearum in relation to development of nonassimilating structures and infection. We identified an ATG8 homolog F. graminearum...... a pivotal role for supplying nutrients to nonassimilating structures necessary for growth and is important for plant colonization. This also indicates that autophagy is a central mechanism for fungal adaptation to nonoptimal C/N ratios....

  16. NASA Satellite Monitoring of Water Clarity in Mobile Bay for Nutrient Criteria Development

    Science.gov (United States)

    Blonski, Slawomir; Holekamp, Kara; Spiering, Bruce A.

    2009-01-01

    This project has demonstrated feasibility of deriving from MODIS daily measurements time series of water clarity parameters that provide coverage of a specific location or an area of interest for 30-50% of days. Time series derived for estuarine and coastal waters display much higher variability than time series of ecological parameters (such as vegetation indices) derived for land areas. (Temporal filtering often applied in terrestrial studies cannot be used effectively in ocean color processing). IOP-based algorithms for retrieval of diffuse light attenuation coefficient and TSS concentration perform well for the Mobile Bay environment: only a minor adjustment was needed in the TSS algorithm, despite generally recognized dependence of such algorithms on local conditions. The current IOP-based algorithm for retrieval of chlorophyll a concentration has not performed as well: a more reliable algorithm is needed that may be based on IOPs at additional wavelengths or on remote sensing reflectance from multiple spectral bands. CDOM algorithm also needs improvement to provide better separation between effects of gilvin (gelbstoff) and detritus. (Identification or development of such algorithm requires more data from in situ measurements of CDOM concentration in Gulf of Mexico coastal waters (ongoing collaboration with the EPA Gulf Ecology Division))

  17. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation

    Directory of Open Access Journals (Sweden)

    Michael J. McCann

    2016-03-01

    Full Text Available Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis to nutrient stoichiometry (nitrogen and phosphorus and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C and low nutrient conditions (0.5 mg N L−1, 0.083 mg P L−1. The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions.

  18. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation.

    Science.gov (United States)

    McCann, Michael J

    2016-01-01

    Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L(-1), 0.083 mg P L(-1)). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions.

  19. Exploiting genotypic variation in plant nutrient accumulation to alleviate micronutrient deficiency in populations.

    Science.gov (United States)

    Genc, Yusuf; Humphries, Julia M; Lyons, Graham H; Graham, Robin D

    2005-01-01

    More than 2 billion people consume diets that are less diverse than 30 years ago, leading to deficiencies in micronutrients, especially iron (Fe), zinc (Zn), selenium (Se), iodine (I), and also vitamin A. A strategy that exploits genetic variability to breed staple crops with enhanced ability to fortify themselves with micronutrients (genetic biofortification) offers a sustainable, cost-effective alternative to conventional supplementation and fortification programs. This is more likely to reach those most in need, has the added advantages of requiring no change in current consumer behaviour to be effective, and is transportable to a range of countries. Research by our group, along with studies elsewhere, has demonstrated conclusively that substantial genotypic variation exists in nutrient (e.g. Fe, Zn) and nutrient promotor (e.g. inulin) concentrations in wheat and other staple foods. A rapid screening technique has been developed for lutein content of wheat and triticale, and also for pro-vitamin A carotenoids in bread wheat. This will allow cost-effective screening of a wider range of genotypes that may reveal greater genotypic variation in these traits. Moreover, deeper understanding of genetic control mechanisms and development of molecular markers will facilitate breeding programs. We suggest that a combined strategy utilising plant breeding for higher micronutrient density; maximising the effects of nutritional promoters (e.g. inulin, vitamin C) by promoting favourable dietary combinations, as well as by plant breeding; and agronomic biofortification (e.g. adding iodide or iodate as fertiliser; applying selenate to cereal crops by spraying or adding to fertiliser) is likely to be the most effective way to improve the nutrition of populations. Furthermore, the importance of detecting and exploiting beneficial interactions is illustrated by our discovery that in Fe-deficient chickens, circulating Fe concentrations can be restored to normal levels by lutein

  20. [Effects of plant species combination and water body nutrient level on the biomass accumulation and allocation of three kinds functional plants].

    Science.gov (United States)

    Sun, Li-Fang; Sun, Yi-Xiang; Zhou, Chang-Fang; An, Shu-Qing

    2009-10-01

    Four nutrient levels, i.e., 0.5 mg N x L(-1) and 0.1 mg P x L(-1) (I), 1.5 mg N x L(-1) and 0.3 mg P x L(-1) (II), 4.5 mg N x L(-1) and 0.9 mg P x L(-1) (III), and 13.5 mg N x L(-1) and 2.7 mg P x L(-1) (IV), were installed to study the effects of water body's nutrient level, plant species combination, and their interactions on the biomass accumulation and allocation of invasive floating species Eichhornia crassipes, native rooted leaf-floating species Jussiaea stipulacea, and submerged plant Vallisneria spiralis. The total, root, stem, and leaf biomass of E. crassipes and J. stipulacea, either in monoculture or in mixed-culture, increased with increasing water body's nutrient level, their total biomass in treatments III and IV being averagely 54.47% and 102.63% higher than that in treatments I and II, respectively. Under different plant species combination, the total, root, stem, and leaf biomass of V. spiralis showed a declining trend with the increase of nutrient level, and the total biomass of V. spiralis in treatments III and IV was averagely 45.88% lower than that in treatments I and II. The results of two-way ANOVA showed that water body's nutrient level had significant positive effects on the biomass of E. crassipes and J. stipulacea but negative effects on that of V. spiralis, and the effects of plant species combination varied with target plant species.

  1. Effects of Plant Herb Combination Supplementation on Rumen Fermentation and Nutrient Digestibility in Beef Cattle

    Directory of Open Access Journals (Sweden)

    M. Wanapat

    2013-08-01

    Full Text Available Four rumen-fistulated crossbred beef cattle (Brahman native were randomly assigned according to a 4×4 Latin square design experiment to be fed plant herb supplements in their concentrate mixture. The treatments were: without herb supplementation (Control, lemongrass meal supplementation at 100 g/d (L, lemongrass meal supplementation at 100 g/d plus peppermint powder at 10 g/d (LP, and lemongrass meal supplementation at 100 g/d plus peppermint powder at 10 g/d with garlic powder 40 g/d (LPG, respectively. Based on the present study, the DMI and apparent digestibility of DM, OM, aNDF and ADF were not affected by dietary herb supplementation while CP digestibility tended to be decreased by herb supplement. Moreover, NH3-N and BUN were decreased in all herb supplemented treatments and there was a tendency to an increase in ruminal pH in all herb supplemented groups. While there was no change in TVFA and C4 among lemongrass treatments, C2 was decreased in all herb supplemented treatments while C3 was increased. Methane production by calculation was the lowest in the LP and LPG groups. Population sizes of bacteria and protozoa were decreased in all herb supplemented groups, but not fungal zoospores. In all supplemented groups, total viable and proteolytic bacteria were decreased, while amylolytic and cellulolytic bacteria were similar. More importantly, in all herb supplemented groups, there were higher N balances, while there was no difference among treatments on purine derivative (PD excretion or microbial N. Based on the results above, it could be concluded that there was no negative effect on ruminal fermentation characteristics and nutrient utilization by plant herb supplement, but protozoal population and CH4 production were reduced. Thus, lemongrass alone or in combination with peppermint and garlic powder could be used as feed additives to improve rumen fermentation efficiency.

  2. Benchmarking biological nutrient removal in wastewater treatment plants: influence of mathematical model assumptions.

    Science.gov (United States)

    Flores-Alsina, Xavier; Gernaey, Krist V; Jeppsson, Ulf

    2012-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant was compared for a series of model assumptions. Three different model approaches describing BNR are considered. In the reference case, the original model implementations are used to simulate WWTP1 (ASM1 & 3) and WWTP2 (ASM2d). The second set of models includes a reactive settler, which extends the description of the non-reactive TSS sedimentation and transport in the reference case with the full set of ASM processes. Finally, the third set of models is based on including electron acceptor dependency of biomass decay rates for ASM1 (WWTP1) and ASM2d (WWTP2). The results show that incorporation of a reactive settler: (1) increases the hydrolysis of particulates; (2) increases the overall plant's denitrification efficiency by reducing the S(NOx) concentration at the bottom of the clarifier; (3) increases the oxidation of COD compounds; (4) increases X(OHO) and X(ANO) decay; and, finally, (5) increases the growth of X(PAO) and formation of X(PHA,Stor) for ASM2d, which has a major impact on the whole P removal system. Introduction of electron acceptor dependent decay leads to a substantial increase of the concentration of X(ANO), X(OHO) and X(PAO) in the bottom of the clarifier. The paper ends with a critical discussion of the influence of the different model assumptions, and emphasizes the need for a model user to understand the significant differences in simulation results that are obtained when applying different combinations of 'standard' models.

  3. Factors affecting population of filamentous bacteria in wastewater treatment plants with nutrients removal.

    Science.gov (United States)

    Miłobędzka, Aleksandra; Witeska, Anna; Muszyński, Adam

    2016-01-01

    Filamentous population in activated sludge and key operational parameters of full-scale municipal wastewater treatment plants (WWTPs) with bulking problems representative for Poland were investigated with quantitative fluorescence in situ hybridization. Statistical analyses revealed few relationships between operational parameters and biovolume of filamentous bacteria. Sludge age was not only positively correlated with abundance of Chloroflexi (parametric correlation and principal component analysis (PCA)), but also differentiated Microthrix population (analysis of variance (ANOVA)). Phylum Chloroflexi and pH presented a negative relation during the study (PCA). ANOVA showed that pH of influent and sludge volume index (SVI) differentiated abundance of types 0803 and 1851 of Chloroflexi and candidate division TM7. SVI increased along with higher abundance of Microthrix (positive parametric and non-parametric correlations and positive relation in PCA). Biovolumes of morphotypes 0803 and 1851 of Chloroflexi were differentiated by organic matter in influent, also by nutrients in the case of Chloroflexi type 1851. Chemical and biological oxygen demands (COD and BOD5, respectively) were negatively correlated with Microthrix. COD also differentiated the abundance of Haliscomenobacter hydrossis. Results of the study can be used to prevent WWTPs from excessive proliferation of filamentous bacteria and operational problems caused by them--bulking and foaming of activated sludge.

  4. Altitudinal patterns and controls of plant and soil nutrient concentrations and stoichiometry in subtropical China

    Science.gov (United States)

    He, Xianjin; Hou, Enqing; Liu, Yang; Wen, Dazhi

    2016-04-01

    Altitude is a determining factor of ecosystem properties and processes in mountains. This study investigated the changes in the concentrations of carbon (C), nitrogen (N), and phosphorus (P) and their ratios in four key ecosystem components (forest floor litter, fine roots, soil, and soil microorganisms) along an altitudinal gradient (from 50 m to 950 m a.s.l.) in subtropical China. The results showed that soil organic C and microbial biomass C concentrations increased linearly with increasing altitude. Similar trends were observed for concentrations of total soil N and microbial biomass N. In contrast, the N concentration of litter and fine roots decreased linearly with altitude. With increasing altitude, litter, fine roots, and soil C:N ratios increased linearly, while the C:N ratio of soil microbial biomass did not change significantly. Phosphorus concentration and C:P and N:P ratios of all ecosystem components generally had nonlinear relationships with altitude. Our results indicate that the altitudinal pattern of plant and soil nutrient status differs among ecosystem components and that the relative importance of P vs. N limitation for ecosystem functions and processes shifts along altitudinal gradients.

  5. Deconstructing responses of dragonfly species richness to area, nutrients, water plant diversity and forestry.

    Science.gov (United States)

    Honkanen, Merja; Sorjanen, Aili-Maria; Mönkkönen, Mikko

    2011-06-01

    Understanding large-scale variation in species richness in relation to area, energy, habitat heterogeneity and anthropogenic disturbance has been a major task in ecology. Ultimately, variation in species richness results from variation in individual species occupancies. We studied whether the individual species occupancy patterns are determined by the same candidate factors as total species richness. We sampled 26 boreal forest ponds for dragonflies (Odonata) and studied the effects of shoreline length, water vascular plant species density (WVPSD), availability of nutrients, intensity of forestry, amount of Sphagnum peat cover and pH on dragonfly species richness and individual dragonfly species. WVPSD and pH had a strong positive effect on species richness. Removal of six dragonfly species experiencing strongest responses to WVPSD cancelled the relationship between species richness and WVPSD. By contrast, removal of nine least observed species did not affect the relationship between WVPSD and species richness. Thus, our results showed that relatively common species responding strongly to WVPSD shaped the observed species richness pattern whereas the effect of least observed, often rare, species was negligible. Also, our results support the view that, despite of the great impact of energy on species richness at large spatial scales, habitat heterogeneity can still have an effect on species richness in smaller scales, even overriding the effects of area.

  6. Biodegradation of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) with plant and nutrients and their effects on the microbial ecological kinetics.

    Science.gov (United States)

    Sun, Guangdong; Zhang, Xu; Hu, Qing; Zhang, Heqing; Zhang, Dayi; Li, Guanghe

    2015-02-01

    Four pilot-scale test mesocosms were conducted for the remediation of organochlorine pesticides (OCPs)-contaminated aged soil. The results indicate that the effects on degradation of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) were in the following order: nutrients/plant bioaugmentation (81.18 % for HCHs; 85.4 % for DDTs) > nutrients bioaugmentation > plant bioaugmentation > only adding water > control, and nutrients/plant bioaugmentation greatly enhanced the degradation of HCHs (81.18 %) and DDTs (85.4 %). The bacterial community structure, diversity and composition were assessed by 454-pyrosequencing of 16S recombinant RNA (rRNA), whereas the abundance of linA gene was determined by quantitative polymerase chain reaction. Distinct differences in bacterial community composition, structure, and diversity were a function of remediation procedure. Predictability of HCH/DDT degradation in soils was also investigated. A positive correlation between linA gene abundance and the removal ratio of HCHs was indicated by correlation analyses. A similar relationship was also confirmed between the degradation of HCHs/DDTs and the abundance of some assemblages (Gammaproteobacteria and Flavobacteria). Our results offer microbial ecological insight into the degradation of HCHs and DDTs in aged contaminated soil, which is helpful for the intensification of bioremediation through modifying plant-microbe patterns, and cessation of costly and time-consuming assays.

  7. Identification of Appropriate Reference Genes for Normalization of miRNA Expression in Grafted Watermelon Plants under Different Nutrient Stresses.

    Science.gov (United States)

    Wu, Weifang; Deng, Qin; Shi, Pibiao; Yang, Jinghua; Hu, Zhongyuan; Zhang, Mingfang

    2016-01-01

    Watermelon (Citrullus lanatus) is a globally important crop belonging to the family Cucurbitaceae. The grafting technique is commonly used to improve its tolerance to stress, as well as to enhance its nutrient uptake and utilization. It is believed that miRNA is most likely involved in its nutrient-starvation response as a graft-transportable signal. The quantitative real-time reverse transcriptase polymerase chain reaction is the preferred method for miRNA functional analysis, in which reliable reference genes for normalization are crucial to ensure the accuracy. The purpose of this study was to select appropriate reference genes in scion (watermelon) and rootstocks (squash and bottle gourd) of grafted watermelon plants under normal growth conditions and nutrient stresses (nitrogen and phosphorus starvation). Under nutrient starvation, geNorm identified miR167c and miR167f as two most stable genes in both watermelon leaves and squash roots. miR166b was recommended by both geNorm and NormFinder as the best reference in bottle gourd roots under nutrient limitation. Expression of a new Cucurbitaceae miRNA, miR85, was used to validate the reliability of candidate reference genes under nutrient starvation. Moreover, by comparing several target genes expression in qRT-PCR analysis with those in RNA-seq data, miR166b and miR167c were proved to be the most suitable reference genes to normalize miRNA expression under normal growth condition in scion and rootstock tissues, respectively. This study represents the first comprehensive survey of the stability of miRNA reference genes in Cucurbitaceae and provides valuable information for investigating more accurate miRNA expression involving grafted watermelon plants.

  8. Identification of Appropriate Reference Genes for Normalization of miRNA Expression in Grafted Watermelon Plants under Different Nutrient Stresses

    Science.gov (United States)

    Wu, Weifang; Deng, Qin; Shi, Pibiao; Yang, Jinghua; Hu, Zhongyuan; Zhang, Mingfang

    2016-01-01

    Watermelon (Citrullus lanatus) is a globally important crop belonging to the family Cucurbitaceae. The grafting technique is commonly used to improve its tolerance to stress, as well as to enhance its nutrient uptake and utilization. It is believed that miRNA is most likely involved in its nutrient-starvation response as a graft-transportable signal. The quantitative real-time reverse transcriptase polymerase chain reaction is the preferred method for miRNA functional analysis, in which reliable reference genes for normalization are crucial to ensure the accuracy. The purpose of this study was to select appropriate reference genes in scion (watermelon) and rootstocks (squash and bottle gourd) of grafted watermelon plants under normal growth conditions and nutrient stresses (nitrogen and phosphorus starvation). Under nutrient starvation, geNorm identified miR167c and miR167f as two most stable genes in both watermelon leaves and squash roots. miR166b was recommended by both geNorm and NormFinder as the best reference in bottle gourd roots under nutrient limitation. Expression of a new Cucurbitaceae miRNA, miR85, was used to validate the reliability of candidate reference genes under nutrient starvation. Moreover, by comparing several target genes expression in qRT-PCR analysis with those in RNA-seq data, miR166b and miR167c were proved to be the most suitable reference genes to normalize miRNA expression under normal growth condition in scion and rootstock tissues, respectively. This study represents the first comprehensive survey of the stability of miRNA reference genes in Cucurbitaceae and provides valuable information for investigating more accurate miRNA expression involving grafted watermelon plants. PMID:27749935

  9. Linking nutrient strategies with plant size along a grazing gradient:Evidence fromLeymus chinensis in a natural pasture

    Institute of Scientific and Technical Information of China (English)

    LI Xi-liang; LIU Zhi-ying; REN Wei-bo; DING Yong; JI Lei; GUO Feng-hui; HOU Xiang-yang

    2016-01-01

    Studying the changes in nutrient use strategies induced by grazing can provide insight into the process of grassland degra-dation and is important for improving grassland quality and enhancing ecosystem function. Dominant species in meadow steppe can optimize their use of limiting resources; however, the regulation of nutrient use strategies across grazing gradients is not fuly understood. Therefore, in this study, we report anin situ study in which the impact of grazing rates on nutrient use strategies ofLeymus chinensis, the dominant plant species in eastern Eurasian temperate steppes, was investigated. We conducted a large randomized controled experiment (conducted continuously for ifve years in grassland plots in a natural pasture in Hailar, eastern Mongolia Plateau, China) to assess the effects of grazing rate treatments (0.00, 0.23, 0.34, 0.46, 0.69, and 0.92 adult cattle unit (AU) ha–1) onL. chinensis along a grazing gradient and employed a random sampling approach to compare the accumulation, alocation, and stoichiometry of C, N, and P in leaves and stems. Our ifndings demonstrated the folows: (i) The height ofL. chinensis decreased with an increase in the grazing gradient, and the concentrations of C, N, and P signiifcantly increased; (i) the accumulation of C, N, and P per individual was negatively correlated with the con-centration of aboveground tissues, suggesting that there was a tradeoff inL. chinensis between nutrient accumulation and concentration at the individual scale; (ii) the leaf-to-stem ratio of C, N, and P accumulation increased with grazing intensity, indicating a tradeoff in nutrient alocation and plant size at the individual plant level; and (iv) grazing rates were negatively correlated with the ratios of C:N and C:P in the stem; however, these ratios in leaves signiifcantly increased with grazing intensity. Our ifndings suggest thatL. chinensisin meadow steppe adapts to grazing disturbance through tradeoffs between plant size and

  10. Development of mobile electron beam plant for environmental applications

    Science.gov (United States)

    Han, Bumsoo; Kim, Jinkyu; Kang, Wongu; Choi, Jang Seung; Jeong, Kwang-Young

    2016-07-01

    Due to the necessity of pilot scale test facility for continuous treatment of wastewater and gases on site, a mobile electron beam irradiation system mounted on a trailer has developed. This mobile electron beam irradiation system is designed for the individual field application with self-shielded structure of steel plate and lead block which will satisfy the required safety figures of International Commission on Radiological Protection (ICRP). Shielding of a mobile electron accelerator of 0.7 MeV, 30 mA has been designed and examined by Monte Carlo technique. Based on a 3-D model of electron accelerator shielding which is designed with steel and lead shield, radiation leakage was examined using the Monte Carlo N-Particle Transport (MCNP) Code. Simulations with two different versions (version 4c2 and version 5) of MCNP code showed agreements within statistical uncertainties, and the highest leakage expected is 5.5061×10-01 (1±0.0454) μSv/h, which is far below the tolerable radiation dose limit for occupational workers. This unit could treat up to 500 m3 of liquid waste per day at 2 kGy or 10,000 N m3 of gases per hour at 15 kGy.

  11. Investigating the efficiency and kinetic coefficients of nutrient removal in the subsurface artificial wetland of Yazd wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Mahdi Farzadkia

    2015-01-01

    Full Text Available Background: Investigating the performance of naturally operated treatment plants may be due to the fact that they cannot be operated as desired, or that they should be modified to achieve good performance e.g. for nutrients removal. The advantage of kinetic coefficient determination is that the model can be adjusted to fit data and then used for analyzing alternatives to improve the process. This study investigates the efficiency of subsurface artificial wetland and determines its kinetic coefficients for nutrient removal. Methods: The present study investigated the kinetics of biological reactions that occurred in subsurface wetland to remove wastewater nutrient. Samples were taken from 3 locations of wetlands for 6 months. The nutrient content was determined through measuring Total Kjehldahl Nitrogen (TKN, ammonium, nitrate, and phosphate values. Results: Average levels for TKN, ammonium, nitrate, and phosphate in effluent of control wetland were 41.15, 23.59, 1.735, and 6.43 mg/L, and in wetland with reeds were 28.91, 19.99, 1.49 and 5.63 mg/L, respectively. First-order, second-order, and Stover-Kincannon models were applied and analyzed using statistical parameters obtained from the models (Umax, KB. Conclusion: The nutrients removal at Yazd wastewater treatment plant was remarkable, and the presence of reeds in wetland beds was not very efficient in improving system performance. Other more efficient plants are suggested to be evaluated in the system. Stover-Kincannon kinetic model provided predictions having the closest relationship with actual data obtained from the field.

  12. Limestone, gypsum and residual effect of fertilizers in the biomass production and nutrient cycling of millet plants

    Directory of Open Access Journals (Sweden)

    Maria da Conceição Santana Carvalho

    2014-09-01

    Full Text Available Cover crops can provide a higher nutrient cycling. This study aimed to determine the effect of annual applications of gypsum and lime to the soil surface and of fertilizer doses to the previous crop (soybean in the dry biomass production and nutrient accumulation by plants of pearl millet grown in succession, under no-tillage system. The experimental design was randomized blocks, in a 4x4 factorial scheme, with four replications. Treatments consisted of the combination of four types of soil conditioner (lime, lime + gypsum, gypsum and control, split in three parts (2 t ha-1 of lime and 1,0 t ha-1 of gypsum; 2 t ha-1 of lime and 1 t ha-1 of gypsum; and 1 t ha-1 of lime and 0.5 t ha-1 of gypsum, and four fertilizing rates with P (triple and simple superphosphate and K (potassium chloride (0%, 50%, 100% and 150% of the recommended fertilizing, applied at the sowing of the previous crop (soybean. Liming provided increments in the dry biomass production and in the accumulation of nutrients (N, P, K, Ca, Mg and S by millet plants. The application of gypsum did not increase the millet dry biomass yield. The use of increasing rates of fertilizers in the previous crop (soybean increased the biomass dry matter, density and accumulation of nutrients by millet plants. The intercropping of millet as a cover crop, with the residual effect of the fertilizer applied in the summer crop, provided a nutrient cycling that can be used by the following crops.

  13. Internal efficiency of nutrient utilization: what is it and how to measure it during vegetative plant growth?

    Science.gov (United States)

    Santa-María, Guillermo E; Moriconi, Jorge I; Oliferuk, Sonia

    2015-06-01

    Efficient use of the resources required by plants to sustain crop production is considered an important objective in agriculture. In this context, the idea of developing crops with an enhanced ability to utilize mineral nutrients already taken up by roots has been proposed. In recent years powerful tools that allow the association of phenotypic variation with high-resolution genetic maps of crop plants have also emerged. To take advantage of these tools, accurate methods are needed to estimate the internal efficiency of nutrient utilization (ENU) at the whole-plant level, which requires using suitable conceptual and experimental approaches. Here we highlight some inconsistencies in the definitions of ENU commonly used for ENU 'phenotyping' at the vegetative stage and suggest that it would be convenient to adopt a dynamic definition. The idea that ENU should provide information about the relationship between carbon and mineral nutrient economies mainly during the period under which growth is actually affected by low internal nutrient concentration is here advocated as a guide for the selection of adequate operational ENU formulae for the vegetative stage. The desirability of using experimental approaches that allow removal of the influence of nutrient acquisition efficiency on ENU estimations is highlighted. It is proposed that the use of simulation models could help refine the conclusions obtained through these experimental procedures. Some potential limitations in breeding for high ENU are also considered. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  14. Availability of nutrients and toxic heavy metals in marigold plants=Disponibilidade de nutrientes e metais pesados tóxicos em plantas de calêndula

    Directory of Open Access Journals (Sweden)

    Herbert Nacke

    2012-10-01

    Full Text Available Availability of nutrients and toxic heavy metals in marigold plants. This study was performed aiming to assess the availability of nutrients and toxic heavy metals present in marigold plants (Calendula officinalis treated with different fertilizers. The treatments were arranged in factorial scheme (2 x 2 x 3 in a completely randomized experimental design (CRD, with two textures of soil (sandy and clayey, two forms of fertilization (organic and chemical and three fertilization levels (without fertilization, recommended dose, and twice the recommended dose totaling 12 treatments, with four replications. The results showed that the clayey soil promoted the availability of N P, K, Mg, Cu, Zn and Fe; on the other hand, the sandy soil favored the availability of Ca, Mn, Pb and Cr. The organic fertilization provided higher levels of P and Fe, while the leaf tissue of marigold plants chemically fertilized presented higher concentrations of K and Mn.Realizou-se este trabalho com o objetivo de avaliar a disponibilidade de nutrientes e de metais pesados tóxicos presentes em plantas de calêndula (Calendula officinalis após diferentes tipos de adubação. Os tratamentos foram arranjados em esquema fatorial (2 x 2 x 3 dispostos em delineamento experimental inteiramente casualizado (DIC, sendo duas texturas de solo, (argilosa e arenosa, duas formas de adubação (química e orgânica e três doses de adubação (sem adubação, dose recomendada e o dobro da dose recomendada, totalizando 12 tratamentos com quatro repetições. Os resultados demonstraram que os solos argilosos favoreceram a disponibilidade de N P, K, Mg, Cu, Zn e Fe; os solos de textura arenosa favoreceram a disponibilidade de Ca, Mn, Pb e Cr. A adubação orgânica disponibilizou maiores teores de P e Fe, enquanto o tecido foliar de plantas de calêndula adubadas com adubação química apresentaram concentrações maiores de K e Mn.

  15. Silicon isotope fractionation between rice plants and nutrient solution and its significance to the study of the silicon cycle

    Science.gov (United States)

    Ding, T. P.; Tian, S. H.; Sun, L.; Wu, L. H.; Zhou, J. X.; Chen, Z. Y.

    2008-12-01

    The silicon isotope fractionation between rice plant and nutrient solution was studied experimentally. Rice plants were grown to maturity with the hydroponic culture in a naturally lit glasshouse. The nutrient solution was sampled for 14 times during the whole rice growth period. The rice plants were collected at various growth stages and different parts of the plants were sampled separately. The silica contents of the samples were determined by the gravimetric method and the silicon isotope compositions were measured using the SiF 4 method. In the growth process, the silicon content in the nutrient solution decreased gradually from 16 mM at starting stage to 0.1-0.2 mM at harvest and the amount of silica in single rice plant increased gradually from 0.00013 g at start to 4.329 g at harvest. Within rice plant the SiO 2 fraction in roots reduced continuously from 0.23 at the seedling stage, through 0.12 at the tiller stage, 0.05 at the jointing stage, 0.023 at the heading stage, to 0.009 at the maturity stage. Accordingly, the fraction of SiO 2 in aerial parts increased from 0.77, through 0.88, 0.95, 0.977, to 0.991 for the same stages. The silicon content in roots decreased from the jointing stage, through the heading stage, to the maturity stage, parallel to the decrease of silicon content in the nutrient solution. At the maturity stage, the silicon content increased from roots, through stem and leaves, to husks, but decreased drastically from husks to grains. These observations show that transpiration and evaporation may play an important role in silica transportation and precipitation within rice plants. It was observed that the δ30Si of the nutrient solution increased gradually from -0.1‰ at start to 1.5‰ at harvest, and the δ30Si of silicon absorbed by bulk rice plant increased gradually from -1.72‰ at start to -0.08‰ at harvest, reflecting the effect of the kinetic silicon isotope fractionation during silicon absorption by rice plants from nutrient

  16. Use of the nutrient film technique as a method for assessment of plant response to salt stress in the cereals

    Directory of Open Access Journals (Sweden)

    P. K. Martin

    2014-01-01

    Full Text Available The nutrient film technique (NFT/rockwool system was adapted for use as a method for assessing the response of wheat and barley to saline stress. Wheat plants grown by the NFT/rockwool system in 200 mmol NaCl were vegetatively more vigorous and were more fertile than when suspended over bowls containing the same saline nutrient solution. Signifcant intervarietal differential responses were observed in both wheat and barley for vegetative vigour under saline stress. By increasing the concentration of NaCI to 260 mM and growing seedlings in miniaturized rockwool plugs, a screening system for salt tolerance in wheat, which allowed substantial plant numbers to be tested, was made possible. Seedlings which survived 4 weeks of this treatment could be successfully rescued into soil, where they developed normally.

  17. THE IMPACT OF FRESH SAWDUST AND DRY PIG MANURE PRODUCED ON SAWDUST BEDDING APPLICATION ON THE NUTRIENTS MOBILITY IN SOIL AND SUGAR BEET YIELD

    Directory of Open Access Journals (Sweden)

    Peter Kováčik

    2013-07-01

    Full Text Available The objective of the pot trial carried out at the area of the Slovak University of Agriculture in Nitra was to determine the impact of dry pig manure produced on the sawdust bedding and sawdust litter on the level of nutrients’ mobility in the soil and sugar beet yield. The achieved results showed that one month after the sawdust and manure application to the soil, the contents of mobile nutrients (Nan, P, K, Ca, Mg in soil were lower than in the control unfertilized treatment. The sawdust litter immobilized nutrients more considerably than manure. Four months after the manure application into soil, its immobilization effect was not evident. On the contrary, the manure increased the mobile nutrients content in soil. In the second year of experiment the immobilization effect of sawdust litter was proved even four months after its application into soil. The application of manure increased considerably the beet root yield. The maximum root yield was determined in the treatment where the highest dose of manure was applied. The minimum root yield was detected in the treatment where the highest dose of sawdust litter was applied.

  18. The Effect of Using Mobile Technology-Based Methods That Record Food or Nutrient Intake on Diabetes Control and Nutrition Outcomes: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Judi Porter

    2016-12-01

    Full Text Available (1 Background: Mobile technologies may be utilised for dietary intake assessment for people with diabetes. The published literature was systematically reviewed to determine the effect of using mobile electronic devices to record food or nutrient intake on diabetes control and nutrition outcomes; (2 Methods: The review protocol was registered with PROSPERO: registration number CRD42016050079, and followed PRISMA guidelines. Original research of mobile electronic devices where food or nutrient intake was recorded in people with diabetes with any treatment regimen, and where this intervention was compared with usual care or alternative treatment models, was considered. Quality was assessed using the Quality Criteria Checklist for Primary Research; (3 Results: Nine papers formed the final library with a range of interventions and control practices investigated. The food/nutrient intake recording component of the intervention and patient engagement with the technology was not well described. When assessed for quality, three studies rated positive, five were neutral and one negative. There was significantly greater improvement in HbA1c in the intervention group compared to the control group in four of the nine studies; (4 Conclusion: Based on the available evidence there are no clear recommendations for using technology to record dietary data in this population.

  19. The Effect of Using Mobile Technology-Based Methods That Record Food or Nutrient Intake on Diabetes Control and Nutrition Outcomes: A Systematic Review.

    Science.gov (United States)

    Porter, Judi; Huggins, Catherine E; Truby, Helen; Collins, Jorja

    2016-12-17

    (1) Background: Mobile technologies may be utilised for dietary intake assessment for people with diabetes. The published literature was systematically reviewed to determine the effect of using mobile electronic devices to record food or nutrient intake on diabetes control and nutrition outcomes; (2) Methods: The review protocol was registered with PROSPERO: registration number CRD42016050079, and followed PRISMA guidelines. Original research of mobile electronic devices where food or nutrient intake was recorded in people with diabetes with any treatment regimen, and where this intervention was compared with usual care or alternative treatment models, was considered. Quality was assessed using the Quality Criteria Checklist for Primary Research; (3) Results: Nine papers formed the final library with a range of interventions and control practices investigated. The food/nutrient intake recording component of the intervention and patient engagement with the technology was not well described. When assessed for quality, three studies rated positive, five were neutral and one negative. There was significantly greater improvement in HbA1c in the intervention group compared to the control group in four of the nine studies; (4) Conclusion: Based on the available evidence there are no clear recommendations for using technology to record dietary data in this population.

  20. Nutrients can enhance the abundance and expression of alkane hydroxylase CYP153 gene in the rhizosphere of ryegrass planted in hydrocarbon-polluted soil.

    Science.gov (United States)

    Arslan, Muhammad; Afzal, Muhammad; Amin, Imran; Iqbal, Samina; Khan, Qaiser M

    2014-01-01

    Plant-bacteria partnership is a promising strategy for the remediation of soil and water polluted with hydrocarbons. However, the limitation of major nutrients (N, P and K) in soil affects the survival and metabolic activity of plant associated bacteria. The objective of this study was to explore the effects of nutrients on survival and metabolic activity of an alkane degrading rhizo-bacterium. Annual ryegrass (Lolium multiflorum) was grown in diesel-contaminated soil and inoculated with an alkane degrading bacterium, Pantoea sp. strain BTRH79, in greenhouse experiments. Two levels of nutrients were applied and plant growth, hydrocarbon removal, and gene abundance and expression were determined after 100 days of sowing of ryegrass. Results obtained from these experiments showed that the bacterial inoculation improved plant growth and hydrocarbon degradation and these were further enhanced by nutrients application. Maximum plant biomass production and hydrocarbon mineralization was observed by the combined use of inoculum and higher level of nutrients. The presence of nutrients in soil enhanced the colonization and metabolic activity of the inoculated bacterium in the rhizosphere. The abundance and expression of CYP153 gene in the rhizosphere of ryegrass was found to be directly associated with the level of applied nutrients. Enhanced hydrocarbon degradation was associated with the population of the inoculum bacterium, the abundance and expression of CYP153 gene in the rhizosphere of ryegrass. It is thus concluded that the combination between vegetation, inoculation with pollutant-degrading bacteria and nutrients amendment was an efficient approach to reduce hydrocarbon contamination.

  1. Integrated plant nutrient system - with special emphasis on mineral nutriton and biofertilizers for Black pepper and cardamom - A review.

    Science.gov (United States)

    K P, Sangeeth; R, Suseela Bhai

    2016-05-01

    Integrated Plant Nutrition System (IPNS) as a concept and farm management strategy embraces and transcends from single season crop fertilization efforts to planning and management of plant nutrients in crop rotations and farming systems on a long-term basis for enhanced productivity, profitability and sustainability. It is estimated that about two-thirds of the required increase in crop production in developing countries will have to come from yield increases from lands already under cultivation. IPNS enhances soil productivity through a balanced use of soil nutrients, chemical fertilizers, combined with organic sources of plant nutrients, including bio-inoculants and nutrient transfer through agro-forestry systems and has adaptation to farming systems in both irrigated and rainfed agriculture. Horticultural crops, mainly plantation crops, management practices include application of fertilizers and pesticides which become inevitable due to the depletion of soil organic matter and incidence of pests and diseases. The extensive use of chemical fertilizers in these crops deteriorated soil health that in turn affected the productivity. To revitalize soil health and to enhance productivity, it is inexorable to enrich the soil using microorganisms. The lacunae observed here is the lack of exploitation of indigenous microbes having the potential to fix atmospheric nitrogen (N) and to solubilize Phosphorus (P) and Potassium (K). The concept of biofertilizer application appears to be technically simple and financially feasible, but the task of developing biofertilizers with efficient strains in appropriate combinations in a consortia mode is not easier. More than developing consortia, a suitable delivery system to discharge the microbial inoculants warranted much effort. This review focuses on the integrated plant nutrition system incorporating biofertilizer with special emphasis on developing and formulating biofertilizer consortium.

  2. The introduction of mobile plant clinics to Uganda

    DEFF Research Database (Denmark)

    Danielsen, Solveig; Mutebi, Emmanuel

    of Agriculture, Animal Industry and Fisheries (MAAIF) have recently included the plant clinics in their new 5-year Development Strategy and Investment Plan to strengthen disease control and surveillance. The present report is the first output of a newly started research project between University of Copenhagen......, Makerere University and CABI. The purpose of this study was to gather results and lessons learned from the pilot period to inform future plant clinic interventions. The study covers issues of organisation and management, clinic operation and performance as well as clinic use and preliminary evidence...

  3. Plants sensitivity on nickel under different conditions of iron or calcium concentration in the nutrient medium

    Directory of Open Access Journals (Sweden)

    Renata Matraszek

    2013-12-01

    Full Text Available The sensitivity of six vegetable plants on nickel at early stages of their growth was investigated by index of tolerance. Besides the possibility of nickel fitostabilization by additional application of iron or calcium was tested. The experiment was conducted on Petri dishes. Different concentrations of nickel (0; 0,03; 0,06mM Ni as nickel sulphate, iron (0,05; O,OlmM Fe as Fe2+ citrate and calcium (0,50; 0,75; lmM Ca as calcium carbonate were added. Taking into consideration the sensitivity, investigated vegetables can be ordered in the following way: Cucurbita pepo conv. giromontiina L.>Lactuca sativa L.>Sinapis alba L.>Spinacia oleracea L.=Zea mays var. saccharata Kcke.>Phaseolus vulgaris L. Positive, statistically significant effect ofnickel fitostabilization (0,03 or 0,06mM Ni on elongative growth by the iron application (0,10mM Fe was shown for Zea mays var. saccharata Kcke independently of Ni concentration in the nutrient medium as well as for Sinapis alba L. and Phaseolus vulgaris L. in 0,06mM Ni. Addition as much as 0,75mM Ca in the presence 0,03mM Ni had positive result on Sinapis alba L and Phaseolus vulgaris L. seedlings as well as on Zea mays var. saccharata Kcke and Lactuca sativa L. roots and Cucurbita pepo convar. giromontiina L. shoots. Addition of 0,75mM Ca in the presence 0,06mM Ni promoted elongative growth of Zea mays var. saccharata Kcke seedlings. Application lmM Ca resulted in the promotion of elongative growth of Zea mays var. saccharata Kcke. roots (0,03mM Ni as well as Spinacia oleracea L. roots (0,06mM Ni.

  4. Emission enhancement of laser-induced breakdown spectroscopy by localized surface plasmon resonance for analyzing plant nutrients.

    Science.gov (United States)

    Ohta, Takayuki; Ito, Masafumi; Kotani, Takashi; Hattori, Takeaki

    2009-05-01

    We demonstrate the monitoring of plant nutrients in leaves of Citrus unshiu and Rhododendron obtusum using low-energy (laser-induced breakdown spectroscopy. The raw plant leaf was successfully ablated without desiccation before laser irradiation, by applying metallic colloidal particles to the leaf surface. The emission intensity with the metallic particles was larger than that without the particles. This result indicates an improvement of the sensitivity and the detection limit of laser-induced breakdown spectroscopy. The emission enhancement was caused by localized surface plasmon resonance and was dependent on the size and material of metallic particles.

  5. Effect of Bolax gummifera rhizosphere on the mobility of soil nutrients in a subantarctic environment (Mont Martial, Ushuaia-Argentina)

    Science.gov (United States)

    Otero, Xosé Luis; Pérez-Alberti, Augusto; Gónzalez, Adrián; Macias, Felipe

    2013-04-01

    The study area, Mount Martial, is located in the South of Argentina, in the Tierra de Fuego province (54°S, 68°W). The climate in Tierra del Fuego is temperate-cold and humid, with a strong and markedly seasonal oceanic influence. The mean air temperature that we recorded in the study zone, at 1050 m above sea level, between February 2005 and January 2010 was -1.9° C, with an absolute maximum of 12.5° C and an absolute minimum of -12.8° C. Although we have no rainfall data, in Ushuaia, which is close to sea level, the mean annual rainfall for 1961-1970 was 550 mm; however, it would be inaccurate to extrapolate this value given the marked variability in precipitation favoured by the relief. Biogeographically, the area is included in the so-called "Andean Desert", which is almost barren of large plants and with poor vegetable cover. At 800 a.s.l., the vegetation consists of shrubs of specialised taxons such as Bolax gummifera, Moschopsis rosulata and Saxifraga magellanica. In the present study, samples of Bolax gummifera rhizosphere (Umbelliferae), bulk soil and subsurface soils (>5 cm to rock layer) were collected from a small homogeneous area (≈500m2). The soils were characterized by analysis of pH (H2O and KCl), electrical conductivity, total organic carbon, total nitrogen, organic carbon, iron extracted with sodium pyrophosphate, and particle size. Sequential extraction of Fe in the samples was also carried out to determine the following fractions: F1: exchangeable fraction (extracted with 1M MgCl2), F2: amorphous Fe oxyhydroxides (extracted with sodium ascorbate-citrate buffering to pH 8 with sodium bicarbonate), F3: crystalline Fe oxyhydroxides (extracted with 0.11 sodium citrate+ sodium bicarbonate +3 g of sodium dithionite), and F4: organic Fe (extracted with 0.02M HNO3+30%H2O2 at 85°C) and bioavailability nutrients (soluble in Mehlich 3 extratant). The results obtained for the basic physicochemical characteristics of the soils revealed some

  6. Biogas container - mobile plant concept for the decentralized power generation; Biogascontainer. Mobiles Anlagenkonzept zur dezentralen Energiegewinnung

    Energy Technology Data Exchange (ETDEWEB)

    Warncke, Jessica; Orth, Maik [Innovations- und Bildungszentrum Hohen Luckow e.V., Hohen Luckow (Germany); Schlegel, Mathias [Rostock Univ. (Germany); Steinhagen, Katrin [ROSOMA GmbH, Rostock-Marienehe (Germany)

    2011-07-01

    In the framework of a cooperation project of the Federal Ministry of Economics and Technology was developed a small biogas system, that is concepted in the order of a 40-foot standard container, that is modular structured, works energy-independent and optional can be used mobile. First rank the system was designed for biogas production in developing and emerging countries. Now there are inter alia also concrete inquiries of german partners. (orig.)

  7. Spontaneous plant colonization of brownfield soil and sludges and effects on substrate properties and pollutants mobility

    Science.gov (United States)

    Rocco, Claudia; Agrelli, Diana; Gonzalez, Maria Isabel; Mingo, Antonio; Motti, Riccardo; Stinca, Adriano; Coppola, Ida; Adamo, Paola

    2017-04-01

    This work was done on brownfield soil and sludges from a dismantled steel plant, moderately polluted by heavy metals (mainly Pb and Zn), 1) to analyzed the effects of substrate properties and environmental conditions on spontaneous vegetation; 2) to assess changes in the chemical properties of soils and sludges, with particular reference to the mobility and bioavailability of pollutants, induced by spontaneous plants revegetation. From 2006 to 2011, spontaneous plant colonization was monitored in the presence or absence of acidic peat both inside the degraded brownfield site and after transferal into a nearby Oak Park environment. During the five experimental years the vegetation growth was monitored using phytosociological method and data analyzed statistically. Both substrates, before and after plant growth, were analyzed for main chemical properties. Metals mobility and bioavailability was assessed using single (H2O; DTPA) and sequential extractions (EU-BCR). At the end of the experiment, plant ability to uptake metal was evaluated on selected species. Overall, 57 plant species grew healthily on the substrates. The combination of soil and sludges with peat resulted in an effective revegetation with a sensible increasing of plants biomass. Most of the species were found in the park (91%), showing plant colonization was mainly affected by the immediate environment rather than by substrate properties. Furthermore, after the five years, the substrate properties (pH, O.C.) were slightly affected by plant growth and, although metal pollutants in both substrates are characterized by low water solubility and DTPA availability, after plants growth an increase (even if not significant) of rhizospheric Cu, Fe, Mn and Zn solubility in H2O was detected. Metals speciation indicated a low risk of Pb and Zn mobility being either largely trapped in the mineralogical structure of oxides and silicates and occluded in easily reducible manganese or iron oxides. Restricted metal

  8. Plant nutrient acquisition strategies in tundra species: at which soil depth do species take up their nitrogen?

    Science.gov (United States)

    Limpens, Juul; Heijmans, Monique; Nauta, Ake; van Huissteden, Corine; van Rijssel, Sophie

    2016-04-01

    The Arctic is warming at unprecedented rates. Increased thawing of permafrost releases nutrients locked up in the previously frozen soils layers, which may initiate shifts in vegetation composition. The direction in which the vegetation shifts will co-determine whether Arctic warming is mitigated or accelerated, making understanding successional trajectories urgent. One of the key factors influencing the competitive relationships between plant species is their access to nutrients, in particularly nitrogen (N). We assessed the depth at which plant species took up N by performing a 15N tracer study, injecting 15(NH4)2SO4 at three depths (5, 15, 20 cm) into the soil in arctic tundra in north-eastern Siberia in July. In addition we explored plant nutrient acquisition strategy by analyzing natural abundances of 15N in leaves. We found that vascular plants took up 15N at all injection depths, irrespective of species, but also that species showed a clear preference for specific soil layers that coincided with their functional group (graminoids, dwarf shrubs, cryptogams). Graminoids took up most 15N at 20 cm depth nearest to the thaw front, with grasses showing a more pronounced preference than sedges. Dwarf shrubs took up most 15N at 5 cm depth, with deciduous shrubs displaying more preference than evergreens. Cryptogams did not take up any of the supplied 15N . The natural 15N abundances confirmed the pattern of nutrient acquisition from deeper soil layers in graminoids and from shallow soil layers in both deciduous and evergreen dwarf shrubs. Our results prove that graminoids and shrubs differ in their N uptake strategies, with graminoids profiting from nutrients released at the thaw front, whereas shrubs forage in the upper soil layers. The above implies that graminoids, grasses in particular, will have a competitive advantage over shrubs as the thaw front proceeds and/or superficial soil layers dry out. Our results suggest that the vertical distribution of nutrients

  9. Model of how plants sense zinc deficiency

    NARCIS (Netherlands)

    Assuncao, A.G.L.; Persson, D.P.; Husted, S.; Schjorring, J.K.; Alexander, R.D.; Aarts, M.G.M.

    2013-01-01

    Plants are capable of inducing a range of physico-chemical and microbial modifications of the rhizosphere which can mobilize mineral nutrients or prevent toxic elements from entering the roots. Understanding how plants sense and adapt to variations in nutrient availability is essential in order to d

  10. Responses of plant diversity and primary productivity to nutrient addition in aStipa baicalensis grassland, China

    Institute of Scientific and Technical Information of China (English)

    YU Li; SONG Xiao-long; ZHAO Jian-ning; WANG Hui; BAI Long; YANG Dian-lin

    2015-01-01

    Nutrient addition can affect the structure and diversity of grassland plant communities, thus alter the grassland productivity. Studies on grassland plant community composition, structure and diversity in response to nutrient addition have an import-ant theoretical and practical signiifcance for the scientiifc management of grassland, protection of plant diversity and the recovery of degraded grassland. A randomized block design experiment was conducted with six blocks of eight treatments each: control (no nutrient addition) and K, P, N, PK, NK, NP, and NPK addition. We evaluated plant composition, height, coverage, density, and aboveground biomass to estimate primary productivity and plant diversity. Results showed that al treatments increased primary productivity signiifcantly (P<0.05) with the exception of the K and the NPK treatments had the greatest effect, increasing aboveground biomass 2.46 times compared with the control (P<0.05). One-way ANOVA and factorial analysis were used for the species richness, Shannon-Wiener index, Pielou index and aboveground biomass, and the relationships between the diversity indices and aboveground biomass were determined through linear regression. We found that fertilization altered the community structure; N (but not P or K) addition increased the proportion of perennial rhizome grasses and signiifcantly reduced that of perennial forbs (P<0.05), thus it presented a trend of decrease in species richness, Shannon-Wiener and Pielou indexex, respectively. Only the main effects of N had signiifcant impacts on both the diversity indices and the aboveground biomass (P<0.05), and the interactions between N-P, N-K, P-K and N-P-K could be neglected. With fertilization, plant diversity (correlation coefifcient, –0.61), species richness (–0.49), and species even-ness (–0.51) were al negatively linearly correlated with primary productivity. The correlations were al signiifcant (P<0.01). Scientiifc nutrient management is an effective

  11. Strain Identity of the Ectomycorrhizal Fungus Laccaria bicolor Is More Important than Richness in Regulating Plant and Fungal Performance under Nutrient Rich Conditions

    Directory of Open Access Journals (Sweden)

    Christina Hazard

    2017-09-01

    Full Text Available Effects of biodiversity on productivity are more likely to be expressed when there is greater potential for niche complementarity. In soil, chemically complex pools of nutrient resources should provide more opportunities for niche complementarity than chemically simple pools. Ectomycorrhizal (ECM fungal genotypes can exhibit substantial variation in nutrient acquisition traits and are key components of soil biodiversity. Here, we tested the hypothesis that increasing the chemical complexity and forms of soil nutrients would enhance the effects of intraspecific ECM diversity on host plant and fungal productivity. In pure culture, we found substantial variation in growth of strains of the ECM fungus Laccaria bicolor on a range of inorganic and organic forms of nutrients. Subsequent experiments examined the effects of intraspecific identity and richness using Scots pine (Pinus sylvestris seedlings colonized with different strains of L. bicolor growing on substrates supplemented with either inorganic or organic forms of nitrogen and phosphorus. Intraspecific identity effects on plant productivity were only found under the inorganic nutrient amendment, whereas intraspecific identity affected fungal productivity to a similar extent under both nutrient treatments. Overall, there were no significant effects of intraspecific richness on plant and fungal productivity. Our findings suggest soil nutrient composition does not interact strongly with ECM intraspecific richness, at least under experimental conditions where mineral nutrients were not limiting. Under these conditions, intraspecific identity of ECM fungi becomes more important than richness in modulating plant and fungal performance.

  12. Comparative phloem Mobility of nickel in nonsenescent plants. [Pisum sativa L. ; Pelargonium zonale L

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, P.M.; Chamel, A.

    1986-06-01

    /sup 63/Ni was applied to nonsenescent source leaves and found to be transported to sink tissues in pea (Pisum saativum L.) and geranium plants (Pelargonium zonale L.). The comparative mobilities (percent tracer transported out of source leaf division % /sup 86/Rb transported) for /sup 63/Ni in peas was 2.12 and in geranium 0.25. The value for the phloem mobile /sup 86/Rb was 1.00. By contrast, the comparative mobility of /sup 45/Ca, which is relatively immobile in the phloem, was low (0.05 in peas, 0.00 in geranium). Interruption of the phloem pathway between source and sink leaves by steam girdling almost completely inhibited /sup 63/Ni accumulation in the sink leaves of both species. The authors conclude that Ni is transported from nonsenescent source leaves to sink tissues via the phloem of leguminous and nonleguminous plants.

  13. Growth and fruit development of mangosteen (Garcinia mangostana L. in related with plant nutrients during phenological development

    Directory of Open Access Journals (Sweden)

    Nilnond, C.

    2005-12-01

    Full Text Available The imbalance or deficiency of essential nutrients in soils and plant may cause poor fruit quality of mangosteen fruit; translucent flesh disorder (TFD and internal gumming fruits. Therefore, an investigation of nutrient changes in soils and plant (root, branch, leaf and fruit of mangosteen (Garcinia mangostana L. during phenological development is a useful guideline for fertilizer management. This research aimed to investigate the pattern of plant nutrients accumulation and nutrient requirement during phenological development of the mangosteen trees. Soil sampling was taken at 4 depths; 0-15, 15-30, 30-50 and 50-100 cm, from soil surface around the middle of the tree canopy and analyzed for some important chemical and physical properties. Roots, branches, leaves and fruits from mangosteen trees at 4 periods of growth; preflowering, flowering, fruit development (from bloom to 7th week and harvesting were sampled, and analyzed related to the changes of soil nutrients. The results indicated that the soil texture varied from sandy clay loam to clay loam (Ruso soil series (Ro; Typic Pelehumults. In addition, the natural soils in mangosteen orchards was strong acid to very strong acid (pH 4.62-4.93, soil:water = 1:5. Mangosteen trees might take high amounts of nutrients from the surface soils (0-15 cm as follows: N, K, Mg and S for growth in the preflowering period; N, K, S and B in the flowering period; K, Ca and Mg in the 1st half of fruit development period (bloom to 7th week of fruit development and P in the 2nd half of fruit development period (7th week of fruit development to harvest compared to other growth periods. The results also showed that in the root, branch and leaf, mangosteen trees required higher amounts of Ca for growth in the preflowering period; K, Mg and S in the flowering period; N in the 1st half of fruit development period and K, Mg and B in the 2nd half of fruit development period compared to other growth periods. In the

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

    Science.gov (United States)

    Moyin-Jesu, Emmanuel Ibukunoluwa

    2007-08-01

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

  15. Variabilidade de nutrientes em plantas de milho cultivado em talhão manejado homogeneamente Corn plant nutrient variability in an homogeneously managed crop field

    Directory of Open Access Journals (Sweden)

    Zaqueu Fernando Montezano

    2008-12-01

    Full Text Available O conhecimento da variabilidade da nutrição de plantas e da produtividade em áreas cultivadas pode fornecer importantes subsídios na racionalização do uso de insumos e auxiliar no manejo da fertilidade do solo. O objetivo deste trabalho foi avaliar a variabilidade da nutrição mineral de plantas de milho por meio do fracionamento de um talhão cultivado comercialmente em células de manejo e verificar as relações com a produtividade. O estudo foi realizado na Fazenda Alto Alegre, em Planaltina (GO, em área de 373 hectares de Latossolo Vermelho-Amarelo Distroférrico, cultivado com milho na safra 2003/04. Traçado um polígono da área, procedeu-se sua divisão em 80 células de manejo de quatro hectares cada uma. A amostragem de folhas em cada célula seguiu uma diagonal com 12 pontos para compor uma amostra composta. Realizou-se a análise dos macro e micronutrientes nas folhas. A produtividade para cada célula foi obtida por meio de colhedora equipada com GPS. Na análise da variabilidade dos resultados foram considerados os parâmetros estatísticos descritivos. O teste ausência de correlação foi realizado com o nível de significância de 5%. A variabilidade da concentração dos nutrientes na folha indicadora do milho foi considerada baixa para N, P, K, S e Mg; e média para Ca, Cu, Fe, Mn e Zn. A variabilidade da produtividade de milho revelou diferenças de produção para cada célula analisada. Os coeficientes de correlação entre os nutrientes e a produtividade foram significativamente diferentes de zero (pThe knowledge of variability of plant nutrition and grain productivity in cultivated areas may provide important information for rational use of fertilizers and soil amendments. The objective of this case study was to determine the corn plant mineral nutrition variability through the fractionation of a commercial grown corn field into small management cells. The study was carried out at the farm Alto Alegre in

  16. Nutrient cycling strategies.

    NARCIS (Netherlands)

    Breemen, van N.

    1995-01-01

    This paper briefly reviews pathways by which plants can influence the nutrient cycle, and thereby the nutrient supply of themselves and of their competitors. Higher or lower internal nutrient use efficiency positively feeds back into the nutrient cycle, and helps to increase or decrease soil

  17. Nutrient cycling strategies.

    NARCIS (Netherlands)

    Breemen, van N.

    1995-01-01

    This paper briefly reviews pathways by which plants can influence the nutrient cycle, and thereby the nutrient supply of themselves and of their competitors. Higher or lower internal nutrient use efficiency positively feeds back into the nutrient cycle, and helps to increase or decrease soil fertili

  18. Effects of organic plant oils and role of oxidation on nutrient utilization in juvenile rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Lund, Ivar; Dalsgaard, Anne Johanne Tang; Jacobsen, Charlotte

    2013-01-01

    digestibility was furthermore examined. Four organic oils with either a relatively high or low content of polyunsaturated fatty acids were considered: linseed oil, rapeseed oil, sunflower oil and grapeseed oil. Substituting FO with organic oils did not affect feed intake (P.0.05), FCR or SGR (P.0.05) despite......Producing organic fish diets requires that the use of both fishmeal and fish oil (FO) be minimized and replaced by sustainable, organic sources. The purpose of the present study was to replace FO with organic oils and evaluate the effects on feed intake, feed conversion ratio (FCR), daily specific...... growth rate (SGR) and nutrient digestibility in diets in which fishmeal protein was partly substituted by organic plant protein concentrates. It is prohibited to add antioxidants to organic oils, and therefore the effects of force-oxidizing the oils (including FO) on feed intake and nutrient...

  19. Utilization of the water soluable fraction of wheat straw as a plant nutrient source

    Science.gov (United States)

    Mackowiak, C. L.; Garland, J. L.

    1990-01-01

    Recovery of water soluble, inorganic nutrients from the inedible portion of wheat was found to be an effective means of recycling nutrients within hydroponic systems. Through aqueous extraction (leaching), 60 percent of the total inorganic nutrient weight was removed from wheat straw and roots, although the recovery of individual nutrients varied. Leaching also removed about 20 percent of the total organic carbon from the biomass. In terms of dry weight, the leachate was comprised of approximately 60 percent organic and 40 percent inorganic compounds. Direct use of wheat straw leachate in static hydroponic systems had an inhibitory effect on wheat growth, both in the presence and absence of microorganisms. Biological treatment of leachate either with a mixed microbial community or the oyster mushroom Pleurotus ostreatus L., prior to use in hydroponic solutions, significantly reduced both the organic content and the inhibitory effects of the leachate. The inhibitory effects of unprocessed leachate appear to be a result of rapidly acting phytotoxic compounds that are detoxified by microbial activity. Leaching holds considerable promise as a method for nutrient recycling in a Controlled Ecological Life Support System (CELSS).

  20. Paddy plants inoculated with PGPR show better growth physiology and nutrient content under saline condition

    Directory of Open Access Journals (Sweden)

    Yachana Jha

    2013-09-01

    Full Text Available The possible role of plant growth-promoting rhizobacteria (PGPR to alleviate salt stress during plant growth has been studied on paddy rice (Oryza sativa L. 'GJ-17' under greenhouse conditions; the study included growth parameters, mineral concentration, and antioxidant enzyme level. Salinity reduced plant growth, but PGPR inoculation reduced its harmful effect up to 1% salinity. Plants inoculated with PGPR under saline conditions showed 16% higher germination, 8% higher survival, 27% higher dry weight, and 31% higher plant height. Similarly, PGPR inoculated plants showed increased concentrations of N(26%, P (16%, K (31%, and reduced concentrations of Na (71% and Ca (36% as compared to non-inoculated control plants under saline conditions. Plants inoculated with PGPR under saline conditions also showed significant variations in antioxidant levels and growth physiology. Results suggested that inoculation with PGPR Bacillus pumilus and Pseudomonas pseudoalcaligenes in salt-stressed plants could help to alleviate salt stress in the paddy.

  1. Environmental risk assessment of CRT and PCB workshops in a mobile e-waste recycling plant.

    Science.gov (United States)

    Song, Qingbin; Zeng, Xianlai; Li, Jinhui; Duan, Huabo; Yuan, Wenyi

    2015-08-01

    The mobile e-waste recycling equipment was chosen as the object of this study, including manual dismantling, mechanical separation of cathode ray tubes (CRTs), and printed circuit boards (PCBs) in the two independent workshops. To determine the potential environmental contamination, the noise, the heavy metals (Cu, Cd, Pb), and the environmental impacts of the e-waste recycling processes in the two workshops of the mobile plant have been evaluated in this paper. This study determined that when control measures are employed, the noise within the two workshops (e-waste recycling process as a whole.

  2. Multiple impacts of the plant growth-promoting rhizobacterium Variovorax paradoxus 5C-2 on nutrient and ABA relations of Pisum sativum

    OpenAIRE

    Jiang, Fan; Chen, Lin; Belimov, Andrey A; Shaposhnikov, Alexander I.; Gong, Fan; Meng, Xu; Hartung, Wolfram; Jeschke, Dieter W.; Davies, William J.; Dodd, Ian C.

    2012-01-01

    Resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. To understand further how the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCd)-containing rhizobacterium Variovorax paradoxus 5C-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (ABA) and ABA metabolism were studied in pea (Pisum sativum) plants following rhizosphere bacter...

  3. Isolation of ethyl acetic based AGF bio-nutrient and its application on the growth of Capsicum annum L. plants

    Science.gov (United States)

    Hendrawan, Sonjaya, Yaya; Khoerunnisa, Fitri; Musthapa, Iqbal; Nurmala, Astri Rizki

    2015-12-01

    The study aimed to obtain the bionutrient derived from extraction of AGF leafs in ethyl acetic solvents and to explore its application on the plant growth of capsicum annum L. (curly red chili). Particularly, the fraction of secondary metabolites groups composed bionutrient was intensively elucidated by liquid vacuum chromatography technique. The characterization of secondary metabolites groups was conducted through several methods, i.e. thin layer chromatography, phytochemical screening, and FTIR spectroscopy. The AGF extracts based bionutrient then was applied on capsicum annum L. plants with dosage of 2 and 10 mL/L. The ethyl acetic solvent and commercial nutrient of Phonska and pesticide of curacron (EC 500) were selected as a blank and a positive control to evaluate the growth pattern of capsicum annum L., respectively. The result showed that the CF 1 dan CF2 of AGF extract contained alkaloid and terpenoid of secondary metabolite group, the CF 3, and CF 4 of AGF extracts were dominated by alkaloid, flavonoid, and terpenoid, while the CF 5 of AGF extract contained alkaloid, tannin and terpenoid groups. The CF 2 of AGF extract has the highest growth rate constant of 0.1702 week-1 with the number and heaviest mass of the yield of 82 pieces and 186.60, respectively. It was also showed the significant bio-pesticide activity that should be useful to support plant growth, indicating that AGF extract can be applied as both bio-nutrient and bio-pesticide.

  4. Effects of nutrient and lime additions in mine site rehabilitation strategies on the accumulation of antimony and arsenic by native Australian plants.

    Science.gov (United States)

    Wilson, Susan C; Leech, Calvin D; Butler, Leo; Lisle, Leanne; Ashley, Paul M; Lockwood, Peter V

    2013-10-15

    The effects of nutrient and lime additions on antimony (Sb) and arsenic (As) accumulation by native Australian and naturalised plants growing in two contaminated mine site soils (2,735 mg kg(-1) and 4,517 mg kg(-1) Sb; 826 mg kg(-1) and 1606 As mgkg(-1)) was investigated using a glasshouse pot experiment. The results indicated an increase in soil solution concentrations with nutrient addition in both soils and also with nutrient+lime addition for Sb in one soil. Metalloid concentrations in plant roots were significantly greater than concentrations in above ground plant parts. The metalloid transfer to above ground plant parts from the roots and from the soil was, however, low (ratio of leaf concentration/soil concentration≪1) for all species studied. Eucalyptus michaeliana was the most successful at colonisation with lowest metalloid transfer to above ground plant parts. Addition of nutrients and nutrients+lime to soils, in general, increased plant metalloid accumulation. Relative As accumulation was greater than that of Sb. All the plant species studied were suitable for consideration in the mine soil phytostabilisation strategies but lime additions should be limited and longer term trials also recommended.

  5. Testing plant use of mobile vs immobile soil water sources using stable isotope experiments.

    Science.gov (United States)

    Vargas, Ana I; Schaffer, Bruce; Yuhong, Li; Sternberg, Leonel da Silveira Lobo

    2017-07-01

    We tested for isotope exchange between bound (immobile) and mobile soil water, and whether there is isotope fractionation during plant water uptake. These are critical assumptions to the formulation of the 'two water worlds' hypothesis based on isotope profiles of soil water. In two different soil types, soil-bound water in two sets of 19-l pots, each with a 2-yr-old avocado plant (Persea americana), were identically labeled with tap water. After which, one set received isotopically enriched water whereas the other set received tap water as the mobile phase water. After a dry down period, we analyzed plant stem water as a proxy for soil-bound water as well as total soil water by cryogenic distillation. Seventy-five to 95% of the bound water isotopically exchanged with the mobile water phase. In addition, plants discriminated against (18) O and (2) H during water uptake, and this discrimination is a function of the soil water loss and soil type. The present experiment shows that the assumptions for the 'two water worlds' hypothesis are not supported. We propose a novel explanation for the discrepancy between isotope ratios of the soil water profile and other water compartments in the hydrological cycle. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  6. Mobilities

    DEFF Research Database (Denmark)

    simple movements of people, goods, and information from A to B. The ‘mobilities turn’ has made it its hallmark to explore the ‘more than’ effects of a world increasingly on the move. This new title in the Routledge Series ‘Critical Concepts in Built Environment’ creates a state-of-the-art reference work......The world is on the move. This is a widespread understanding by many inhabitants of contemporary society across the Globe. But what does it actually mean? During over one decade the ‘mobilities turn’ within the social sciences have provided a new set of insights into the repercussions of mobilities...... to social networks, personal identities, and our relationship to the built environment. The omnipresence of mobilities within everyday life, high politics, technology, and tourism (to mention but a few) all point to a key insight harnessed by the ‘mobilities turn’. Namely that mobilities is much more than...

  7. Effect of Plant Growth-Promoting Rhizobacteria on Growth,Nodulation and Nutrient Accumulation of Lentil Under Controlled Conditions

    Institute of Scientific and Technical Information of China (English)

    M.ZAFAR; M.K.ABBASI; M.A.KHAN; A.KHALIQ; T.SULTAN; M.ASLAM

    2012-01-01

    Application of plant growth-promoting rhizobacteria (PGPR) has been shown to increase legume growth and development under field and controlled environmental conditions.The present study was conducted to isolate plant growth-promoting rhizobacteria (PGPR) from the root nodules of lentil (Lens culinaris Medik.) grown in arid/semi-arid region of Punjab,Pakistan and examined their plant growth-promoting abilities.Five bacterial isolates were isolated,screened in vitro for plant growth-promoting (PGP)characteristics and their effects on the growth of lentil were assessed under in vitro,hydroponic and greenhouse (pot experiment)conditions.All the isolates were Gram negative,rod-shaped and circular in form and exhibited the plant growth-promoting attributes of phosphate solubilization and auxin (indole acetic acid,IAA) production.The IAA production capacity ranged in 0.5-11.0 μgmL-1and P solubilization ranged in 3 16 mg L-1.When tested for their effects on plant growth,the isolated strains had a stimulatory effect on growth,nodulation and nitrogen (N) and phosphorus (P) uptake in plants on nutrient-deficient soil.In the greenhouse pot experiment,application of PGPR significantly increased shoot length,fresh weight and dry weight by 65%,43% and 63% and the increases in root length,fresh weight and dry weight were 74%,54% and 92%,respectively,as compared with the uninoculated control.The relative increases in growth characteristics under in vitro and hydroponic conditions were even higher.PGPR also increased the number of pods per plant,1000-grain weight,dry matter yield and grain yield by 50%,13%,28% and 29%,respectively,over the control.The number of nodules and nodule dry mass increased by 170% and 136%,respectively.After inoculation with effective bacterial strains,the shoot,root and seed N and P contents increased,thereby increasing both N and P uptake in plants. The root elongation showed a positive correlation (R2 =0.67) with the IAA

  8. Nutrient enrichment effects on photosynthesis in the wetland plants Typha orientalis and Phormium tenax

    DEFF Research Database (Denmark)

    Sorrell, Brian Keith; Brix, Hans; Tanner, Chris

    -growing species raupo (Typha orientalis) and slower-growing flax (Phormium tenax). Photosynthesis was compared between 9 field locations differing in nutrient availability where the two species co-existed, and in an outdoor growth experiment. Raupo accumulated higher concentrations of nitrogen (N) and especially...

  9. Nutrient uptake, biomass yield and quantitative analysis of aliphatic aldehydes in cilantro plants

    Science.gov (United States)

    The objective of this study was to evaluate the nutrient uptake, biomass production and yield of the major compounds in the essential oil of five genotypes of Coriandrum sativum L. The treatments were four accessions donated by the National Genetic Resources Advisory Council (NGRAC), U.S. Department...

  10. Carbon and nutrient stocks of tea plantations differing in age, genotype and plant population density

    NARCIS (Netherlands)

    Kamau, D.M.; Spiertz, J.H.J.; Oenema, O.

    2008-01-01

    Tea (Camellia sinensis L.) is a perennial evergreen shrub managed intensively for continuous growth of young shoots. Most tea plantations were established at the expense of native forest. Change in carbon (C) and nutrient (nitrogen, phosphorus, potassium (NPK)) accumulation in forests over time has

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

    Science.gov (United States)

    Gong, Wooi-Khoon; Ong, Jin-Eong

    1990-11-01

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

  12. Nutrients in an African Savanna: the consequences of supply heterogeneity for plants and animals

    NARCIS (Netherlands)

    Waal, van der C.

    2010-01-01

    In savannas, trees and grasses co-exist and share resources such as water and nutrients. The ratio between the tree and grass components (i.e., vegetation structure) importantly controls productivity, animal assemblages and earth-atmosphere feedbacks. As the structure of savanna vegetation is inh

  13. The effect of managing nutrients in the performance of anaerobic digesters of municipal wastewater treatment plants.

    Science.gov (United States)

    Demirer, Sibel Uludag; Taskin, Bilgin; Demirer, Goksel N; Duran, Metin

    2013-09-01

    Is it possible to create conditions in the anaerobic digesters to control nutrients without changing the performance of a reactor? This study investigates an answer for this question. To this purpose, anaerobic reactors are operated at high concentrations of Mg(2+) ion to harvest the nutrient ions (NH4 (+) and PO4 (3-)) in the form of struvite, that is, magnesium ammonium phosphate. The effects of this modification on the anaerobic digestion of sewage sludge were investigated in terms of chemical oxygen demand (COD) removal and cumulative CH4 production as well as the changes in the biological diversity. The results showed that approximately 50 % of the nutrients (NH4 (+) and PO4 (3-)) were removed regardless of the method adopted for the addition of Mg(2+) ion, slug or daily dosing. The numbers of Methanosaeta and Methanosarcina in the samples withdrawn prior to and after the addition of Mg(2+) did not show significant difference according to the results obtained from qPCR analyses. The research results showed that the addition of Mg(2+) into the anaerobic digesters in municipal wastewater treatment facilities may help to remove the nutrients from the effluent while recovering in their solid forms.

  14. Characterization of Mineral Nutrients in National Plant Germplasm System (NPGS) Tomato Varieties

    Science.gov (United States)

    Tomato (Solanum lycopersicum) fruit quality and yield are highly dependent on adequate uptake of nutrients. Potassium, magnesium and calcium are essential elements that influence fruit quality traits such as color, uniformity of ripening, hollow fruit, fruit shape, firmness, and acidity. Sodium is...

  15. MedLeaf: Mobile Application for Medicinal Plant Identification Based on Leaf Image

    Directory of Open Access Journals (Sweden)

    Desta Sandya Prasvita

    2013-01-01

    Full Text Available This research proposes MedLeaf as a new mobile application for medicinal plants identification based on leaf image. The application runs on the Android operating system. MedLeaf has two main functionalities, i.e. medicinal plants identification and document searching of medicinal plant. We used Local Binary Pattern to extract leaf texture and Probabilistic Neural Network to classify the image. In this research, we used30 species of Indonesian medicinal plants and each species consists of 48 digital leaf images. To evaluate user satisfaction of the application we used questionnaire based on heuristic evaluation. The evaluation result shows that MedLeaf is promising for medicinal plants identification. MedLeaf will help botanical garden or natural reserve park management to identify medicinal plant, discover new plant species, plant taxonomy and so on. Also, it will help individual, groups and communities to find unused and undeveloped their skill to optimize the potential of medicinal plants. As the results, MedLeaf will increase of their resources, capitals, and economic wealth.

  16. Pectin as a barrier and nutrient source for fungal plant pathogens

    NARCIS (Netherlands)

    Zhang, L.; Kan, van J.A.L.

    2013-01-01

    Fungi that interact with plants gain access to host tissues by actively passing the surface through the cuticle and/or cell wall. Cell walls provide plant tissue strength and structure, and form a barrier against microbial invasion. Plants invest substantial resources in constructing the cell wall a

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

    Directory of Open Access Journals (Sweden)

    Anne eMaillard

    2015-05-01

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

  18. [Feasibility of the use of degraded inedible biomass of plants as a nutrient liquid for hydroponic cultivation].

    Science.gov (United States)

    Guo, S S; Ai, W D; Hou, W H; Shi, W W

    2001-10-01

    Objective. To demonstrate that the recycled liquid, which originated from lettuce inedible biomass degraded by fixed microorganism (correction of microorgannism) and enzyme, can be used as a nutrient solution for lettuce hydroponic cultivation. Method. After biologically degrading the weighted, oven-dried and milled leaves and roots of lettuce in a biological reactor under aerobic condition, the original effluent and its supplemented effluent were used as nutrients for lettuce hydroponic cultivation. Result. The average dried weight (ADW) of lettuce from the original effluent group was approximately half of that from the control group, and the ADW from supplemented effluent group was about equal to that from the control group; some qualities of the lettuce such as a relatively lower content of NO3- from both the original effluent group and the supplemented effluent one improved, and some of those such as a relatively higher content of NO2- dropped. Conclusion. The biologically-degraded effluent was able to be used as nutrient solution for lettuce hydroponic cultivation, although the effects of the inorganic ion-supplemented effluent were much better; the plants of lettuce from the biologically-degraded effluent were safely edible.

  19. MOBILE MORTAR CONCRETE PLANTS FOR BUILDING COMPLEX OF BELARUS: ADVANTAGES AND DISADVANTAGES

    Directory of Open Access Journals (Sweden)

    S. N. Leonovich

    2015-01-01

    Full Text Available The paper considers main advantages and disadvantages of mobile mortar concrete plants in comparison with stationary concrete mixing units. The main idea of the mobility is to provide quick movement. In its turn, this approach imposes some restrictions on dimensions and weights of concrete mixing equipment. However in the context of the concrete mixing equipment and construction site as whole the mobility concept is considered in the form of three components: minimum expenses on site preparation for assembly of a mortar concrete plant, transportability, reduction in installation and startand-adjustment periods. In this regard processing chain for production of concrete and mortar mixes is divided in separate complete operations. Then it is necessary to develop modules which are performing the required operations. Every module is developed in accordance with the size of a shipping container in order to make transportation convenient. Detachable connections are stipulated in the place of module linkages, electrical wiring, pipelines for supply water and chemical admixtures, pneumatics. Henceforth, these connections make it possible to reduce time for on-site assembly and disassembly of the equipment.The paper presents a mobile mortar concrete unit of block-module arrangement which has been developed within the framework of the State Scientific Research Programme at the BNTU. The unit has been manufactured using production capacities of JSC “Viprotekh” and it has been successfully introduced in production process. One of the promising directions is to use the mobile mortar concrete plants which are located and which are operating directly on construction sites. Their economic efficiency becomes higher with an increase of distance to the nearest stationary mortar concrete unit and scope of concreting works. Mobile mortar concrete plants are mainly intended for construction organizations which are realizing construction projects away from urban

  20. Mobile robot based electrostatic spray system for controlling pests on cotton plants in Iraq

    Science.gov (United States)

    Al-Mamury, M.; Manivannan, N.; Al-Raweshidy, H.; Balachandran, W.

    2015-10-01

    A mobile robot based electrostatic spray system was developed to combat pest infestation on cotton plants in Iraq. The system consists of a charged spray nozzle, a CCD camera, a mobile robot (vehicle and arm) and Arduino microcontroller. Arduino microcontroller is used to control the spray nozzle and the robot. Matlab is used to process the image from the CCD camera and to generate the appropriate control signals to the robot and the spray nozzle. COMSOL multi-physics FEM software was used to design the induction electrodes to achieve maximum charge transfer onto the fan spray liquid film resulting in achieving the desired charge/mass ratio of the spray. The charged spray nozzle was operated on short duration pulsed spray mode. Image analysis was employed to investigate the spray deposition on improvised insect targets on an artificial plant.

  1. Mobilization of interactions between functional diversity of plant and soil organisms on nitrogen availability and use

    Science.gov (United States)

    Drut, Baptiste; Cassagne, Nathalie; Cannavacciuolo, Mario; Brauman, Alain; Le Floch, Gaëtan; Cobo, Jose; Fustec, Joëlle

    2017-04-01

    Keywords: legumes, earthworms, microorganisms, nitrogen, interactions Both aboveground and belowground biodiversity and their interactions can play an important role in crop productivity. Plant functional diversity, such as legume based intercrops have been shown to improve yields through plant complementarity for nitrogen use (Corre-Hellou et al., 2006). Moreover, plant species or plant genotype may influence the structure of soil microorganism communities through the composition of rhizodeposits in the rhizosphere (Dennis et al., 2010). Belowground diversity can also positively influence plant performance especially related to functional dissimilarity between soil organisms (Eisenhauer, 2012). Earthworms through their burrowing activity influence soil microbial decomposers and nutrient availability and have thus been reported to increase plant growth (Brown, 1995; Brown et al., 2004). We hypothesize that i) plant functional (genetic and/or specific) diversity associated to functional earthworms diversity are key drivers of interactions balance to improve crop performances and ii) the improvement of plant performances can be related to change in the structure of soil microorganism communities due to the diversity of rhizodeposits and the burrowing activity of earthworms. In a first mesocosm experiment, we investigated the effect of a gradient of plant diversity - one cultivar of wheat (Triticum aestivum L.), 3 different wheat cultivars, and 3 different cultivars intercropped with clover (Trifolium hybridum L.) - and the presence of one (endogeic) or two (endogeic and anecic) categories of earthworms on biomass and nitrogen accumulation of wheat. In a second mesocosm experiment, we investigated the influence of three species with different rhizodeposition - wheat, rapeseed (Brassica napus L. ) and faba bean (Vicia faba L.) in pure stand or intercropped - and the presence of endogeic earthworms on microbial activity and nitrogen availability. In the first experiment

  2. Nutrients can enhance the abundance and expression of alkane hydroxylase CYP153 gene in the rhizosphere of ryegrass planted in hydrocarbon-polluted soil.

    Directory of Open Access Journals (Sweden)

    Muhammad Arslan

    Full Text Available Plant-bacteria partnership is a promising strategy for the remediation of soil and water polluted with hydrocarbons. However, the limitation of major nutrients (N, P and K in soil affects the survival and metabolic activity of plant associated bacteria. The objective of this study was to explore the effects of nutrients on survival and metabolic activity of an alkane degrading rhizo-bacterium. Annual ryegrass (Lolium multiflorum was grown in diesel-contaminated soil and inoculated with an alkane degrading bacterium, Pantoea sp. strain BTRH79, in greenhouse experiments. Two levels of nutrients were applied and plant growth, hydrocarbon removal, and gene abundance and expression were determined after 100 days of sowing of ryegrass. Results obtained from these experiments showed that the bacterial inoculation improved plant growth and hydrocarbon degradation and these were further enhanced by nutrients application. Maximum plant biomass production and hydrocarbon mineralization was observed by the combined use of inoculum and higher level of nutrients. The presence of nutrients in soil enhanced the colonization and metabolic activity of the inoculated bacterium in the rhizosphere. The abundance and expression of CYP153 gene in the rhizosphere of ryegrass was found to be directly associated with the level of applied nutrients. Enhanced hydrocarbon degradation was associated with the population of the inoculum bacterium, the abundance and expression of CYP153 gene in the rhizosphere of ryegrass. It is thus concluded that the combination between vegetation, inoculation with pollutant-degrading bacteria and nutrients amendment was an efficient approach to reduce hydrocarbon contamination.

  3. MOBIL CONTAINER UNIT FOR SEWAGE SLUDGE UTILIZATION FROM SMALL AND MEDIUM WASTWATER TREATMENT PLANTS

    Directory of Open Access Journals (Sweden)

    Stanisław Ledakowicz

    2016-06-01

    Full Text Available The most wastewater treatment plants in Poland are small and medium plants of flow capacity below 1000 m3/d. These plants are not able to build sludge incineration plants and the transportation costs to the nearest plants increase the total costs of wastewater treatment. Polish company Metal Expert together with the French company ETIA and Lodz University of Technology proposed mobile unit for integrated drying and pyrolysis of sewage sludge in a pilot bench scale with capacity of 100 kg/h of dewatered sludge. The pilot plant was mounted in a typical mobile container which could provide service to small and medium wastewater treatment plants offering thermal processing of sewage sludge. This unit consists of KENKI contact dryer and „Spirajoule”® pyrolyser supplied with electricity utilizing the Joule effect, and a boiler, wherein the pyrolysis gases and volatile products are burned producing steam sent to the contact dryer. The bio-char produced during sludge pyrolysis could be utilized for agriculture purposes. During preliminary experiments and short-term exploitation of the unit at Elbląg Wastewater Treatment Plant the obtained results allowed us to make a mass and energy balance depended on the process conditions in the pyrolysis temperature range of 400÷800 °C. Based on the obtained results a calculator was created in the Excel , which enables assessment of pyrolysis products content and making mass and energy balances depended on process parameters such as initial moisture of sludge, pyrolysis temperature and installation output.

  4. Use of alkaline flyash-based products to amend acid soils: Plant growth response and nutrient uptake

    Energy Technology Data Exchange (ETDEWEB)

    Spark, K.M.; Swift, R.S. [University of Queensland, Gatton, Qld. (Australia)

    2008-07-01

    Vast quantities of flyash are generated annually by the burning of coal in the power industry, with most of this material being stockpiled with little prospect of being utilised at present. Two alkaline flyash-based products (FAP) for use as soil amendments (FAP1 and FAP2) have been assessed using glasshouse pot trials to determine the suitability of using these products to treat acid soils. The products both contain about 80% flyash which originated from coal-fired electricity generation. The acid soils used in the study were 2 Podsols and a Ferrosol, all originating from south-east Queensland and ranging in pH (1 : 5 suspension in water) from 4 to 5.5. The flyash products when applied to the soil significantly enhanced growth of maize plants (Zea mays L.), with optimal application rates in the range 1.25-5% w/w. The FAP/soil mixtures and plants were analysed using a range of methods including extraction with DTPA, and plant biomass (aboveground dry matter). The results indicate that in addition to the liming effect, the flyash in the alkaline flyash products may enhance plant growth as a result of increasing the uptake of micro-nutrients such as copper, zinc, and manganese. The study suggests that flyash has the potential to be used as a base material in the production of soil amendment materials that can change soil pH and act as a fertiliser for certain soil micro-nutrients such as Cu, Mn, and Zn.

  5. Perspectives and challenges in the future use of plant nutrients in tilled and mixed agricultural systems.

    Science.gov (United States)

    Bergström, Lars; Goulding, Keith W T

    2005-06-01

    Producing an adequate quantity of healthy food without polluting the environment is a serious challenge for future agriculture around the world. The Food 21 research program in Sweden has researched all aspects--economic, environmental, and social--of sustainable farming systems. This paper presents some of the research from that and other relevant international research programs that have focused on better nutrient-use efficiency, especially for nitrogen and phosphorus. It shows that a range of sustainable solutions to nutrient-use efficiency exists, some of which are complex but some very simple. Government policies, including subsidies; research and technology; and public acceptance of farming practices all combine to create these solutions. Participatory approaches to knowledge transfer are needed, in which scientists, policy makers, farmers, advisers, and consumers exchange information and together build sustainable farming systems.

  6. Plants Responses to Nutrients Follow the Saturation Kinetic Typical of Enzyme Systems: Biological, Economical and Environmental Implications

    Directory of Open Access Journals (Sweden)

    R. P. Lana

    2008-01-01

    Full Text Available Agricultural efficiency has been associated with high plant productivity. However, it is dependent on fertilizers, which are nonrenewable resources. Crop production response to fertilizers is hyperbolic, following the Michaelis-Menten model and the law of diminishing return. Data of crop production (barley, bean, corn, cotton, soybean and wheat as a function of nitrogen, phosphorus, and potassium fertilization were analyzed by Lineweaver-Burk data transformation (L-B, that allows to calculate the amount of a specific nutrient needed to reach half (ks or other percentages of the theoretical maximum response (kmax and the efficiency of fertilizer use (kg of grain/kg of fertilizer. The efficiency of fertilizer use presented exponential decay by increasing fertilization: 55 to 3; 63 to 5; and 47 to 1 kg of corn/kg of fertilizer, by increasing nitrogen, P2O5 and potassium from 40 to 200; 40 to 200; and 60 to 300 kg ha-1, respectively. The L-B can be an alternative to the linear-plateau and polynomial regression methods of recommendation of plant fertilization, in which the fertilizers recommendation should be based on their efficiency of use, avoiding losses of nutrients, environmental pollution, waste of nonrenewable natural resources, and reducing productive costs.

  7. SOIL-PLANT NUTRIENT INTERACTIONS IN TWO MANGROVE AREAS AT SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Ana Paula LANG MARTINS MADI

    2016-01-01

    Full Text Available Los manglares son bosques de arquitectura simple que albergan pocas especies arbóreas, creciendo en un ambiente salino sometido a la influencia de las mareas. El objetivo de este trabajo fue evaluar las posibles interacciones entre las propiedades fisicoquímicas del suelo y la concentración de nutrientes en hojas de diferentes especies de mangle. Se investigó si las diferentes especies que se desarrollan en la misma clase de suelo tienen concentraciones de nutrientes foliares similares, y si las plantas de mangles de la misma especie que se desarrollan en diferentes tipos de suelos tienen concentraciones foliares similares. El estudio se desarrolló en manglares del Estado de Paraná, sur de Brasil, en dos tipos de suelos diferentes (HISTOSOL TIÓNICO Salino sódico y GLEYSOL TIÓNICO Salino sódico. Se analizaron tres especies vegetales diferentes (Avicennia schaueriana, Laguncularia racemosa y Rhizophora mangle. En cada área se delimitaron dos subáreas para recolectar el suelo y las hojas de cada una de las especies. Se tomaron cinco individuos de cada especie del dosel dominante para recoger hojas y muestras de suelo de 0-10 cm, en la proyección de la copa de los árboles seleccionados. Se realizaron análisis univariados y multivariados para probar si las especies de mangle tienen perfiles nutricionales diferentes, y si existe alguna correlación entre las propiedades del suelo con la composición química de las hojas. Los resultados mostraron que el estado nutricional de las especies de mangle es distinto e independiente de los atributos de los suelos en los que se encuentran. Las concentraciones de elementos en las hojas presentan poca correlación con los nutrientes del suelo, lo que sugiere que la absorción de nutrientes por las plantas es selectiva.

  8. Nutrient balance of a two-phase solid manure biogas plant

    OpenAIRE

    Schäfer, Winfried; Evers, Lars; Lehto, Marja; Sorvala, Sanna; Teye, Frederick; Granstedt, Artur

    2005-01-01

    So called "dry fermentation" prototype plants for anaerobic digestion of organic material containing 15-50 % total solids show added advantages compared to slurry digestion plants (Hoffman 2001): Less reactor volume, less process energy, less transport capacity, less odour emissions. However on-farm dry fermentation plants are not common and rarely commercially available. Recent on-farm research (Kusch & Oechsner 2004) and prototype research (Linke 2004) show promising technical solutions for...

  9. Downstairs drivers--root herbivores shape communities of above-ground herbivores and natural enemies via changes in plant nutrients.

    Science.gov (United States)

    Johnson, Scott N; Mitchell, Carolyn; McNicol, James W; Thompson, Jacqueline; Karley, Alison J

    2013-09-01

    1. Terrestrial food webs are woven from complex interactions, often underpinned by plant-mediated interactions between herbivores and higher trophic groups. Below- and above-ground herbivores can influence one another via induced changes to a shared host plant, potentially shaping the wider community. However, empirical evidence linking laboratory observations to natural field populations has so far been elusive. 2. This study investigated how root-feeding weevils (Otiorhynchus sulcatus) influence different feeding guilds of herbivore (phloem-feeding aphids, Cryptomyzus galeopsidis, and leaf-chewing sawflies, Nematus olfaciens) in both controlled and field conditions. 3. We hypothesized that root herbivore-induced changes in plant nutrients (C, N, P and amino acids) and defensive compounds (phenolics) would underpin the interactions between root and foliar herbivores, and ultimately populations of natural enemies of the foliar herbivores in the field. 4. Weevils increased field populations of aphids by ca. 700%, which was followed by an increase in the abundance of aphid natural enemies. Weevils increased the proportion of foliar essential amino acids, and this change was positively correlated with aphid abundance, which increased by 90% on plants with weevils in controlled experiments. 5. In contrast, sawfly populations were 77% smaller during mid-June and adult emergence delayed by >14 days on plants with weevils. In controlled experiments, weevils impaired sawfly growth by 18%, which correlated with 35% reductions in leaf phosphorus caused by root herbivory, a previously unreported mechanism for above-ground-below-ground herbivore interactions. 6. This represents a clear demonstration of root herbivores affecting foliar herbivore community composition and natural enemy abundance in the field via two distinct plant-mediated nutritional mechanisms. Aphid populations, in particular, were initially driven by bottom-up effects (i.e. plant-mediated effects of root

  10. Decoupling of nutrient element cycles in soil and plants across an altitude gradient

    Science.gov (United States)

    Tan, Qiqi; Wang, Guoan

    2016-10-01

    Previous studies have examined the decoupling of C, N, and P under rapid changes in climate. While this may occur in different environment types, such climactic changes have been reported over short distances in mountainous terrain. We hypothesized that the decoupling of C, N, and P could also occur in response to increases in altitude. We sampled soil and plants from Mount Gongga, Sichuan Province, China. Soil C and N were not related to altitude, whereas soil P increased with altitude. Soil N did not change with mean annual temperature (MAT), mean annual precipitation (MAP), vegetation and soil types, whereas soil P varied with MAT and vegetation type. Plant C remained constant with increasing altitude; plant N exhibited a quadratic change trend along the altitude gradient, with a turning point at 2350 m above average sea level; and plant P decreased with altitude. MAP mostly accounted for the variation in plant P. MAT was responsible for the variation of plant N at elevations below 2350 m, whereas MAT and vegetation type were the dominant influential factors of plants growing above 2350 m. Thus, the decoupling of C, N, and P in both soil and plants was significantly affected by altitude.

  11. Digestibilidade dos nutrientes de alimentos volumosos determinada pela técnica dos sacos móveis em eqüinos Nutrient digestibility of forage feed determined using mobile bag technique in horses

    Directory of Open Access Journals (Sweden)

    Vinícius Pimentel Silva

    2009-01-01

    Full Text Available Objetivou-se estimar a digestibilidade de nutrientes de forrageiras em eqüinos utilizando-se a técnica de sacos de náilon móveis. Foram avaliados alfafa (Medicago sativa, amendoim forrageiro (Arachis pintoi, desmódio (Desmodium ovalifolium, estilosantes (Stylosanthes guianensis, guandu (Cajanus cajan, macrotiloma (Macrotyloma axillare e capim-coastcross (Cynodon dactylon cv. coastcross. O delineamento foi em blocos inteiramente casualizados com sete alimentos e cinco blocos (animais. Foram utilizados cinco eqüinos mestiços com 17 a 27 anos de idade e peso vivo médio de 350 kg. O ensaio teve duração de 12 dias: três para a adaptação às baias, cinco para inserção gástrica dos sacos através de sonda nasogástrica e quatro de coleta dos sacos nas fezes. No período pré-experimental de 30 dias, os animais foram mantidos em piquetes com dieta composta de 80% de feno de coastcross e 20% de concentrado. Na confecção dos sacos, utilizou-se náilon com porosidade de 45 µ e dimensão de 7,5 × 2 cm. Em cada saco, foram inseridos 510 mg de matéria seca de amostra do alimento. Os coeficientes de digestibilidade dos nutrientes das forragens foram calculados considerando o resíduo obtido no saco. A digestibilidade dos nutrientes do amendoim, estilosantes e macrotiloma foram superiores à da demais forrageiras, com destaque para a digestibilidade da proteína bruta, cujos valores foram de 91,4; 94,9 e 97,0%, respectivamente. O amendoim e macrotiloma apresentaram digestibilidade da fibra em detergente neutro de 72,3 e 65,2% e da fibra em detergente ácido de 70,9 e 59,4%, respectivamente. O amendoim forrageiro, macrotiloma e estilosantes apresentam digestibilidade dos nutrientes satisfatória e têm potencial para o uso em dietas para eqüinos.This work was carried out to evaluate the nutrient digestibility of forages using mobile bags technique in horses. The forages were lucerne (Medicago sativa, peanut (Arachis pintoi, desmodio

  12. Review: Weak radiofrequency radiation exposure from mobile phone radiation on plants.

    Science.gov (United States)

    Halgamuge, Malka N

    2017-01-01

    The aim of this article was to explore the hypothesis that non-thermal, weak, radiofrequency electromagnetic fields (RF-EMF) have an effect on living plants. In this study, we performed an analysis of the data extracted from the 45 peer-reviewed scientific publications (1996-2016) describing 169 experimental observations to detect the physiological and morphological changes in plants due to the non-thermal RF-EMF effects from mobile phone radiation. Twenty-nine different species of plants were considered in this work. Our analysis demonstrates that the data from a substantial amount of the studies on RF-EMFs from mobile phones show physiological and/or morphological effects (89.9%, p plants seem to be very sensitive to RF-EMFs. Our findings also suggest that plants seem to be more responsive to certain frequencies, especially the frequencies between (i) 800 and 1500 MHz (p plants to date observed the significant trend of radiofrequency radiation influence on plants. Hence, this study provides new evidence supporting our hypothesis. Nonetheless, this endorses the need for more experiments to observe the effects of RF-EMFs, especially for the longer exposure durations, using the whole organisms. The above observation agrees with our earlier study, in that it supported that it is not a well-grounded method to characterize biological effects without considering the exposure duration. Nevertheless, none of these findings can be directly associated with human; however, on the other hand, this cannot be excluded, as it can impact the human welfare and health, either directly or indirectly, due to their complexity and varied effects (calcium metabolism, stress proteins, etc.). This study should be useful as a reference for researchers conducting epidemiological studies and the long-term experiments, using whole organisms, to observe the effects of RF-EMFs.

  13. Enhanced growth of halophyte plants in biochar-amended coastal soil: roles of nutrient availability and rhizosphere microbial modulation.

    Science.gov (United States)

    Zheng, Hao; Wang, Xiao; Chen, Lei; Wang, Zhenyu; Xia, Yang; Zhang, Yipeng; Wang, Hefang; Luo, Xianxiang; Xing, Baoshan

    2017-03-27

    Soil health is essential and irreplaceable for plant growth and global food production, which has been threatened by climate change and soil degradation. Degraded coastal soils are urgently required to reclaim using new sustainable technologies. Interest in applying biochar to improve soil health and promote crop yield has rapidly increased because of its multiple benefits. However, effects of biochar addition on the saline-sodic coastal soil health and halophyte growth were poorly understood. Response of two halophytes, Sesbania (Sesbania cannabina) and Seashore mallow (Kosteletzkya virginica), to the individual or co-application of biochar and inorganic fertilizer into a coastal soil was investigated using a 52-day pot experiment. The biochar alone or co-application stimulated the plant growth (germination, root development, biomass), primarily attributed to the enhanced nutrients availability from the biochar-improved soil health. Additionally, the promoted microbial activities and bacterial community shift towards the beneficial taxa (e.g., Pseudomonas and Bacillus) in the rhizosphere also contributed to the enhanced plant growth and biomass. Our findings showed the promising significance because biochar added at an optimal level (≤5%) could be a feasible option to reclaim the degraded coastal soil, enhance plant growth and production, and increase soil health and food security.

  14. Platinum determination in nutrient plants by inductively coupled plasma mass spectrometry with special respect to the hafnium oxide interference

    Energy Technology Data Exchange (ETDEWEB)

    Lustig, S. [GSF-Research Centre for Environment and Health, Inst. for Ecological Chemistry, Neuherberg (Germany); Zang, S.; Michalke, B. [GSF-Research Centre for Environment and Health, Inst. for Ecological Chemistry, Neuherberg (Germany); Schramel, P. [GSF-Research Centre for Environment and Health, Inst. for Ecological Chemistry, Neuherberg (Germany); Beck, W. [Muenchen Univ. (Germany). Inst. for Inorganic Chemistry

    1997-04-01

    Platinum, emitted from automobile exhaust catalysts, is mainly oxidised in a humic soil, as described previously [1]. An experiment with nutrient plants was carried out to elucidate the bioavailability and accumulation of these platinum containing species. The plants [Allium cepa L. (Weiss, Fruehling), Rephanus sativus L. (Riesenbutter), Vicia faba L. (Hedin, Herzfreya), Zea mays L. (Delis) and Solanum tuberosum L. (Selma)] were grown under natural conditions. For mass balances all ways of platinum transport into and out of the system were monitored during the growing period. Plants growing in untreated soil took up less than 1% of the platinum naturally present in the soil [0.15{+-}0.11 {mu}g kg{sup -1} (78%)]. Plants growing in soil treated with a platinum containing tunnel dust took up slightly more platinum. The comparison of ICPquadrupole-MS results with those obtained by a double focusing magnetic sector ICP-MS showed a strong dependence of the platinum concentration on the Hf-content in the sample. An evaluation method for the correction of the Hf-influence for ICP-quadrupole-MS is presented. (orig.). With 1 fig., 3 tabs.

  15. Effects of Posidonia oceanica beach-cast on germination, growth and nutrient uptake of coastal dune plants.

    Directory of Open Access Journals (Sweden)

    Silvia Del Vecchio

    Full Text Available Seagrass meadows play an important role in marine ecosystems. A part of seagrass production is also exported to adjacent coastal terrestrial systems, possibly influencing their functioning. In this work we experimentally analyzed the effect of Posidonia oceanica beach-cast on plant germination, growth, and nutrient uptake of two plant species (Cakile maritima and Elymus farctus that grow on upper beaches and fore dunes along the Mediterranean coasts. We compared plants growing in simple sand (control with those growing in a substrate enriched with P. oceanica wrack (treatment in laboratory. P. oceanica wrack doubled the N substrate pool and kept the substrate humid. Plants growing in the treated substrate grew faster, were twice as large as those growing in the control substrate, while tissues were enriched in N and P (Cakile by the 1.3 fold in N and 2.5 fold in P; Elymus by 1.5 fold in N and 2 fold in P. Our results suggest a positive effect of seagrass litter for the enhancing of dune species, highlighting its role for the conservation of coastal dune ecosystems.

  16. Effects of Posidonia oceanica beach-cast on germination, growth and nutrient uptake of coastal dune plants.

    Science.gov (United States)

    Del Vecchio, Silvia; Marbà, Núria; Acosta, Alicia; Vignolo, Clara; Traveset, Anna

    2013-01-01

    Seagrass meadows play an important role in marine ecosystems. A part of seagrass production is also exported to adjacent coastal terrestrial systems, possibly influencing their functioning. In this work we experimentally analyzed the effect of Posidonia oceanica beach-cast on plant germination, growth, and nutrient uptake of two plant species (Cakile maritima and Elymus farctus) that grow on upper beaches and fore dunes along the Mediterranean coasts. We compared plants growing in simple sand (control) with those growing in a substrate enriched with P. oceanica wrack (treatment) in laboratory. P. oceanica wrack doubled the N substrate pool and kept the substrate humid. Plants growing in the treated substrate grew faster, were twice as large as those growing in the control substrate, while tissues were enriched in N and P (Cakile by the 1.3 fold in N and 2.5 fold in P; Elymus by 1.5 fold in N and 2 fold in P). Our results suggest a positive effect of seagrass litter for the enhancing of dune species, highlighting its role for the conservation of coastal dune ecosystems.

  17. Groundwater Availability Alters Soil-plant Nutrient Cycling in a Stand of Invasive, N-fixing Phreatophytes

    Science.gov (United States)

    Dudley, B. D.; Miyazawa, Y.; Hughes, F.; Ostertag, R.; Kettwich, S. K.; MacKenzie, R.; Dulaiova, H.; Waters, C. A.; Bishop, J.; Giambelluca, T. W.

    2013-12-01

    N-fixing phreatophytic trees are common in arid and semi-arid regions worldwide, and can play significant roles in modifying hydrology and soil-plant nutrient cycling where they are present. In light of reductions in groundwater levels in many arid regions we estimated annual transpiration rates at a stand level, and alterations to C, N and P accretion in soils as a function of groundwater depth in a ca.120 year old stand of Prosopis pallida along an elevation gradient in coastal leeward Hawaii. We measured sapflow and stand level sapwood area to quantify transpiration, and calculated groundwater transpiration rates using P. pallida stem water δ18O values. By measuring soil resistivity, we were able to compare the volume of groundwater transpired by these trees to groundwater depth across the stand. We examined nutrient deposition and accretion in soils in lowland areas of the stand with accessible shallow groundwater, compared to upland areas with no groundwater access, as indicated by stem water δ18O values. Resistivity results suggested that groundwater was at a height close to sea level throughout the stand. Transpiration was around 1900 m3 ha-1 year-1 in the areas of the stand closest to the sea (where groundwater was at around 1-4 m below ground level) and decreased to around a tenth of that volume where groundwater was not accessible. Litterfall rates over the course of the year studied were 17 times greater at lowland sites, but this litterfall contributed ca. 24 times the N, and 35 times the P of upland sites. Thus, groundwater access contributed to the total mass of nitrogen and phosphorus deposited in the form of litter through higher litter quantity and quality. Total N content of soils was 4.7 times greater and inorganic N pools were eight times higher at lowland plots. These results suggest that groundwater depth can have strong effects on soil-plant nutrient cycling, so that reductions in the availability of shallow groundwater are likely to impact

  18. Conservative nutrient use by big-leaf mahogany (Swietenia macrophylla king planted under contrasting environmental conditions

    Directory of Open Access Journals (Sweden)

    Ernesto Medina

    2014-06-01

    Full Text Available We analyzed the nutritional composition and isotope ratios (C and N of big-leaf mahogany (Swietenia macrophylla King leaves in plantations established on contrasting soils and climates in Central America (State of Quintana Roo, Yucatán, México and South America (State of Pará, Brazil. The objective was to determine the adaptability of this species to large differences in nutrient availability and rainfall regimes. Nutrient concentrations of leaves and soils were determined spectrophotometrically, and isotope ratios were measured using mass spectrometric techniques.In Pará soils were sandier, and acidic, receiving above 2000 mm of rain, whereas in Quintana Roo soils were predominantly clayey, with neutral to alkaline pH due to the underlying calcareous substrate, with about 1300 mm of rain. Leaf area/weight ratio was similar for both sites, but leaves from Quintana Roo were significantly smaller. Average N and K concentrations of adult leaves were similar, whereas Ca concentration was only slightly lower in Pará in spite of large differences in Ca availability. Leaves from this site had slightly higher P and lower Al concentrations. Differences in water use efficiency as measured by the natural abundance of 13C were negligible, the main effect of lower rainfall in Quintana Roo seemed to be a reduction in leaf area. The N isotope signature (δ15N was more positive in Pará than in Quintana Roo, suggesting higher denitrification rates in the former. Results reveal a calciotrophic behavior and a remarkable capacity of mahogany to compensate for large differences in soil texture and nutrient availability.

  19. Varying plant density and harvest time to optimize cowpea leaf yield and nutrient content

    Science.gov (United States)

    Ohler, T. A.; Nielsen, S. S.; Mitchell, C. A.

    1996-01-01

    Plant density and harvest time were manipulated to optimize vegetative (foliar) productivity of cowpea [Vigna unguiculata (L.) Walp.] canopies for future dietary use in controlled ecological life-support systems as vegetables or salad greens. Productivity was measured as total shoot and edible dry weights (DW), edible yield rate [(EYR) grams DW per square meter per day], shoot harvest index [(SHI) grams DW per edible gram DW total shoot], and yield-efficiency rate [(YER) grams DW edible per square meter per day per grams DW nonedible]. Cowpeas were grown in a greenhouse for leaf-only harvest at 14, 28, 42, 56, 84, or 99 plants/m2 and were harvested 20, 30, 40, or 50 days after planting (DAP). Shoot and edible dry weights increased as plant density and time to harvest increased. A maximum of 1189 g shoot DW/m2 and 594 g edible DW/m2 were achieved at an estimated plant density of 85 plants/m2 and harvest 50 DAP. EYR also increased as plant density and time to harvest increased. An EYR of 11 g m-2 day-1 was predicted to occur at 86 plants/m2 and harvest 50 DAP. SHI and YER were not affected by plant density. However, the highest values of SHI (64%) and YER (1.3 g m-2 day-1 g-1) were attained when cowpeas were harvested 20 DAP. The average fat and ash contents [dry-weight basis (dwb)] of harvested leaves remained constant regardless of harvest time. Average protein content increased from 25% DW at 30 DAP to 45% DW at 50 DAP. Carbohydrate content declined from 50% DW at 30 DAP to 45% DW at 50 DAP. Total dietary fiber content (dwb) of the leaves increased from 19% to 26% as time to harvest increased from 20 to 50 days.

  20. Indigenous edible plants as sources of nutrients and health benefitting components (nutraceuticals)

    CSIR Research Space (South Africa)

    Dlamini, N

    2010-08-31

    Full Text Available of antioxidants and other nutraceuticals, and thus be used to develop consumer products. Amaranthus cruentus (Arusha) was selected as the plant based on propagation methods developed by the ARC....

  1. Tomorrow's mobile robots in today's nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    McDermott, K.J.; Pavelek, M.D. II; Roman, H.T.

    1986-01-01

    A primary motivation for utilizing robots in nuclear power plants is maintenance economics and the nuclear industry's concern with reducing personnel radiation exposure to as low as reasonably achievable as recommended by the US Nuclear Regulatory Commission (NRC). Recent studies by Battelle Columbus Laboratories, the Electric Power Research Institute, the NRC and others indicate that robots for surveillance and inspection can be retrofitted into existing boiling water reactor and pressurized water reactor plants, but economics must be evaluated on a case-by-case, site-specific basis, because nuclear power plants in the US are usually different in design. Application areas or robot functions being considered are broad and range from primary containment inspection, reactor maintenance, routine health physics tasks, and various operation and maintenance procedures, to facility decontamination and decommissioning, and post-accident recovery such as at Three Mile Island Unit 2. This paper will discuss the general use of robotic devices in nuclear power plants, the pioneering use of robotics technology at Three Mile Island nuclear power plant, and the field testing of mobile robots at Public Service Electric and Gas Company's Salem and Hope Creek nuclear plants.

  2. Impairment of respiratory chain under nutrient deficiencies in plants: does it play a role in the regulation of iron and sulfur responsive genes?

    Directory of Open Access Journals (Sweden)

    GIANPIERO eVIGANI

    2016-01-01

    Full Text Available Plant production and plant product quality strongly depends on the availability of mineral nutrients. Among them, sulfur (S and iron (Fe play a central role, as they are needed for many proteins of the respiratory chain. Plant mitochondria play essential bioenergetic and biosynthetic functions as well as they have an important role in signalling processes into the cell. Here, by comparing several transcriptomic data sets from plants impaired in their respiratory function with the genes regulated under Fe or S deficiencies obtained from other data sets, nutrient-responsive genes potentially regulated by hypothetical mitochondrial retrograde signalling pathway are evidenced. It leads us to hypothesize that plant mitochondria could be therefore required for regulating the expression of key genes involved both in Fe and S metabolisms.

  3. Impairment of Respiratory Chain under Nutrient Deficiency in Plants: Does it Play a Role in the Regulation of Iron and Sulfur Responsive Genes?

    Science.gov (United States)

    Vigani, Gianpiero; Briat, Jean-François

    2016-01-01

    Plant production and plant product quality strongly depend on the availability of mineral nutrients. Among them, sulfur (S) and iron (Fe) play a central role, as they are needed for many proteins of the respiratory chain. Plant mitochondria play essential bioenergetic and biosynthetic functions as well as they have an important role in signaling processes into the cell. Here, by comparing several transcriptomic data sets from plants impaired in their respiratory function with the genes regulated under Fe or S deficiencies obtained from other data sets, nutrient-responsive genes potentially regulated by hypothetical mitochondrial retrograde signaling pathway are evidenced. It leads us to hypothesize that plant mitochondria could be, therefore, required for regulating the expression of key genes involved both in Fe and S metabolisms. PMID:26779219

  4. Comparison of Coconut Coir, Rockwool, and Peat Cultivations for Tomato Production: Nutrient Balance, Plant Growth and Fruit Quality

    Directory of Open Access Journals (Sweden)

    Jing Xiong

    2017-08-01

    Full Text Available Rockwool (RC and peat are two common substrates used worldwide in horticultural crop production. In recent years environmental and ecological concerns raised the demand for reducing the use of RC and peat. Although coconut coir (CC has been increasingly used as an alternative to RC and peat, it is still needed to comprehensively evaluate the feasibility of CC before widely used. To meet this need, CC, RC, and peat-vermiculite (PVC cultivations were used as tomato cultivation substrates to evaluate their effects on EC, pH and mineral ions in root-zone solution and drainage, nutrient uptake by crops, nutrient balance of cultivation system, plant growth and fruit quality. In general, CC significantly increased K and S uptake by crops, photosynthesis, individual fruit weight and total fruit yield compared to RC, and increased P and K uptake by crops and total fruit yield compared to PVC. Moreover, CC significantly increased organic acid of fruit in first truss compared to both RC and PVC. The uncredited nutrient was overally lower under CC than under RC and PVC (the lower, the better. For all substrates, the blossom-end rot (BER of fruit increased gradually from 3rd to 13th trusses. The BER of fruit was not significantly influenced by CC compared to RC or PVC, but was sginificantly decreased by PVC compared to RC. Our results infer that CC was a potential substrate that could be widely used in tomato production. However, the inhibition of BER was still a challenge when CC was used as cultivation substrate for tomato.

  5. Nutrient removal of a floating plant system receiving low- pollution wastewater: Effects of plant species and influent concentration

    Science.gov (United States)

    Duan, J. J.; Zhao, J. N.; Xue, L. H.; Yang, L. Z.

    2016-08-01

    Plant floating bed was adopted in this study to compare the purification effect of four plant species (Oenanthe javanica, Ipomoea aquatica, Hydrocotyle vulgaris, and Iris sibirica) receiving high and low treated domestic sewage. The experiment was conducted for eight months during the low temperature season. The results indicated that the average removal rates of TN and NH4+-N in I. aquatica floating bed were relatively high both under high and low influent concentration during the first stage of the experiment. During the second stage, H. vulgaris showed the best performance for nitrogen treatment, and the average removal rates of TN were 70.7% and 87.7% under high and low influent concentration, while the average removal rates of NH4 +-N were as high as 98.9% and 98.9%, accordingly. Moreover, H. vulgaris contributed most for plant assimilation to nitrogen removal among different plant floating systems. It was also found that the existence of hydrophytes effectively controlled the rise of water pH value and algae growth and reproduction, which helped to improve the aquatic environment. The results provide engineering parameters for the future design of an ecological remediation technology for low-pollution wastewater purification.

  6. Maximum Plant Uptakes for Water, Nutrients, and Oxygen Are Not Always Met by Irrigation Rate and Distribution in Water-based Cultivation Systems.

    Science.gov (United States)

    Blok, Chris; Jackson, Brian E; Guo, Xianfeng; de Visser, Pieter H B; Marcelis, Leo F M

    2017-01-01

    Growing on rooting media other than soils in situ -i.e., substrate-based growing- allows for higher yields than soil-based growing as transport rates of water, nutrients, and oxygen in substrate surpass those in soil. Possibly water-based growing allows for even higher yields as transport rates of water and nutrients in water surpass those in substrate, even though the transport of oxygen may be more complex. Transport rates can only limit growth when they are below a rate corresponding to maximum plant uptake. Our first objective was to compare Chrysanthemum growth performance for three water-based growing systems with different irrigation. We compared; multi-point irrigation into a pond (DeepFlow); one-point irrigation resulting in a thin film of running water (NutrientFlow) and multi-point irrigation as droplets through air (Aeroponic). Second objective was to compare press pots as propagation medium with nutrient solution as propagation medium. The comparison included DeepFlow water-rooted cuttings with either the stem 1 cm into the nutrient solution or with the stem 1 cm above the nutrient solution. Measurements included fresh weight, dry weight, length, water supply, nutrient supply, and oxygen levels. To account for differences in radiation sum received, crop performance was evaluated with Radiation Use Efficiency (RUE) expressed as dry weight over sum of Photosynthetically Active Radiation. The reference, DeepFlow with substrate-based propagation, showed the highest RUE, even while the oxygen supply provided by irrigation was potentially growth limiting. DeepFlow with water-based propagation showed 15-17% lower RUEs than the reference. NutrientFlow showed 8% lower RUE than the reference, in combination with potentially limiting irrigation supply of nutrients and oxygen. Aeroponic showed RUE levels similar to the reference and Aeroponic had non-limiting irrigation supply of water, nutrients, and oxygen. Water-based propagation affected the subsequent

  7. Effects of grazing regimes on plant traits and soil nutrients in an alpine steppe, Northern Tibetan Plateau.

    Science.gov (United States)

    Sun, Jian; Wang, Xiaodan; Cheng, Genwei; Wu, Jianbo; Hong, Jiangtao; Niu, Shuli

    2014-01-01

    Understanding the impact of grazing intensity on grassland production and soil fertility is of fundamental importance for grassland conservation and management. We thus compared three types of alpine steppe management by studying vegetation traits and soil properties in response to three levels of grazing pressure: permanent grazing (M1), seasonal grazing (M2), and grazing exclusion (M3) in the alpine steppe in Xainza County, Tibetan Plateau. The results showed that community biomass allocation did not support the isometric hypothesis under different grassland management types. Plants in M1 had less aboveground biomass but more belowground biomass in the top soil layer than those in M2 and M3, which was largely due to that root/shoot ratios of dominant plants in M1 were far greater than those in M2 and M3. The interramet distance and the tiller size of the dominant clonal plants were greater in M3 than in M1 and M2, while the resprouting from rhizome buds did not differ significantly among the three greezing regimes. Both soil bulk density and soil available nitrogen in M3 were greater than in M1 at the 15-30 cm soil depth (P = 0.05). Soil organic carbon and soil total nitrogen were greater in M3 than in M1 and M2 (P = 0.05). We conclude that the isometric hypothesis is not supported in this study and fencing is a helpful grassland management in terms of plant growth and soil nutrient retention in alpine steppe. The extreme cold, scarce precipitation and short growing period may be the causation of the unique plant and soil responses to different management regimes.

  8. Effects of grazing regimes on plant traits and soil nutrients in an alpine steppe, Northern Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Jian Sun

    Full Text Available Understanding the impact of grazing intensity on grassland production and soil fertility is of fundamental importance for grassland conservation and management. We thus compared three types of alpine steppe management by studying vegetation traits and soil properties in response to three levels of grazing pressure: permanent grazing (M1, seasonal grazing (M2, and grazing exclusion (M3 in the alpine steppe in Xainza County, Tibetan Plateau. The results showed that community biomass allocation did not support the isometric hypothesis under different grassland management types. Plants in M1 had less aboveground biomass but more belowground biomass in the top soil layer than those in M2 and M3, which was largely due to that root/shoot ratios of dominant plants in M1 were far greater than those in M2 and M3. The interramet distance and the tiller size of the dominant clonal plants were greater in M3 than in M1 and M2, while the resprouting from rhizome buds did not differ significantly among the three greezing regimes. Both soil bulk density and soil available nitrogen in M3 were greater than in M1 at the 15-30 cm soil depth (P = 0.05. Soil organic carbon and soil total nitrogen were greater in M3 than in M1 and M2 (P = 0.05. We conclude that the isometric hypothesis is not supported in this study and fencing is a helpful grassland management in terms of plant growth and soil nutrient retention in alpine steppe. The extreme cold, scarce precipitation and short growing period may be the causation of the unique plant and soil responses to different management regimes.

  9. Experimental biofilms within drinking water treatment plant origin; evaluation of nutrient concentration and temperature influences upon their development

    Directory of Open Access Journals (Sweden)

    Anca FARKAS

    2009-11-01

    Full Text Available From the planktonic free-floating state, microorganisms pass to the solid state, the biofilm, cells being strongly attached to each other and usually to the interface. This changing in cells’ behavior induces surface colonization and complex interactions development within the biofilm. If the biofilm’s role into the natural aquatic habitats is, undoubtedly, a positive one, consisting in water self-purification, drinking water pipe networks biofouling can be responsible for a wide range of water quality and operational problems. This exploratory experiment was performed in order to investigate, in a time interval of 7 days, the influence of certain environmental factors such as nutrient concentration and temperature upon in vitro biofilm’s development, origin in the biofilm of water treatment plant. The method used for in vitro biofilm growth monitoring is the colorimetric measurement of the biomass. Descriptive analyses, including the mean value, variability, trends, correlations and graphic displays were performed. The correlation analysis shown that the biofilm development in the discussed experiment was influenced as by the origin source as by the temperature, time and nutrients concentration. The biomass increment was significantly different for the biofilms with clarifier and sand filter sites origin, grown at 22 oC, while at 8 oC, the differences were not significant from a statistical point of view. For all the dilutions, moments and temperatures considered, the biofilm’s development with clarifier origin registered was significantly higher than the biofilm with sand filter origin.

  10. [Effects of ground surface mulching in tea garden on soil water and nutrient dynamics and tea plant growth].

    Science.gov (United States)

    Sun, Li-tao; Wang, Yu; Ding, Zhao-tang

    2011-09-01

    Taking a 2-year-old tea garden in Qingdao of Shandong Province as test object, this paper studied the effects of different mulching modes on the soil water and nutrient dynamics and tea plant growth. Four treatments were installed, i.e., no mulching (CK), straw mulching (T1), plastic film mulching (T2), and straw plus plastic film mulching (T3). Comparing with CK, mulching could keep the soil water content at a higher level, and enhance the water use efficiency. In treatments T1 and T3, the tea growth water use efficiency and yield water use efficiency increased by 43%-48% and 7%-13%, respectively, compared with CK. Also in treatments T1 and T3, the contents of soil organic matter, available-N, nitrate-N, and ammonium-N increased significantly, with the soil fertility improved, and the leaf nitrate-N content and nitrate reductase activity increased, which promoted the tea growth and yield (12%-13% higher than CK) and made the peak period of bud growth appeared earlier. Considering the tea growth and yield, water and nutrient use efficiency, environment safety and economic benefit, straw mulching could be an effective ground surface mulching mode for young tea garden.

  11. Optimization of isolation and cultivation of bacterial endophytes through addition of plant extract to nutrient media.

    Science.gov (United States)

    Eevers, N; Gielen, M; Sánchez-López, A; Jaspers, S; White, J C; Vangronsveld, J; Weyens, N

    2015-07-01

    Many endophytes have beneficial effects on plants and can be exploited in biotechnological applications. Studies hypothesize that only 0.001-1% of all plant-associated bacteria are cultivable. Moreover, even after successful isolations, many endophytic bacteria often show reduced regrowth capacity. This research aimed to optimize isolation processes and culturing these bacteria afterwards. We compared several minimal and complex media in a screening. Beside the media themselves, two gelling agents and adding plant extract to media were investigated to enhance the number and diversity of endophytes as well as the growth capacity when regrown after isolation. In this work, 869 medium delivered the highest numbers of cultivable bacteria, as well as the highest diversity. When comparing gelling agents, no differences were observed in the numbers of bacteria. Adding plant extract to the media lead to a slight increase in diversity. However, when adding plant extract to improve the regrowth capacity, sharp increases of viable bacteria occurred in both rich and minimal media.

  12. Emerging Trends in Epigenetic Regulation of Nutrient Deficiency Response in Plants.

    Science.gov (United States)

    Sirohi, Gunjan; Pandey, Bipin K; Deveshwar, Priyanka; Giri, Jitender

    2016-03-01

    Diverse environmental stimuli largely affect the ionic balance of soil, which have a direct effect on growth and crop yield. Details are fast emerging on the genetic/molecular regulators, at whole-genome levels, of plant responses to mineral deficiencies in model and crop plants. These genetic regulators determine the root architecture and physiological adaptations for better uptake and utilization of minerals from soil. Recent evidence also shows the potential roles of epigenetic mechanisms in gene regulation, driven by minerals imbalance. Mineral deficiency or sufficiency leads to developmental plasticity in plants for adaptation, which is preceded by a change in the pattern of gene expression. Notably, such changes at molecular levels are also influenced by altered chromatin structure and methylation patterns, or involvement of other epigenetic components. Interestingly, many of the changes induced by mineral deficiency are also inheritable in the form of epigenetic memory. Unravelling these mechanisms in response to mineral deficiency would further advance our understanding of this complex plant response. Further studies on such approaches may serve as an exciting interaction model of epigenetic and genetic regulations of mineral homeostasis in plants and designing strategies for crop improvement.

  13. Design of Mobile Device Display for Nuclear Power Plant Maintenance Considering the Level of Expertise

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2009-10-15

    Maintaining and repairing complex technical facilities such as nuclear power plants requires comprehensive knowledge on a broad range of the system, as well as on operational and safety procedures by the performing maintenance personnel. There exists the need to have access to instruction sheets and parameter tables at the work site. This may not be practicable with printed manuals simply due to their increasing bulk. To cope with this situation, fully mobile wirelessly connected (FMWC) information and communication technologies (ICT) are thought to have high potential for improving field maintenance through increased accessibility and availability of critical information needed in on-site reference or decision making. Among many up-todate technologies, the mobile application to the maintenance support system will be proposed in this paper.

  14. Plant carbon-nutrient interactions control CO{sub 2} exchange in Alaskan wet sedge tundra ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.C.; Shaver, G.R.; Cades, D.H.; Rastetter, E.; Nadelhoffer, K.; Giblin, A.; Laundre, J.; Stanley, A.

    2000-02-01

    The authors explored the long-term (8-yr) effects of separate field manipulations of temperature and nutrient availability on carbon balance in wet sedge tundra near the Arctic Long Term Ecological Research (LTER) site at Toolik Lake, Alaska. Their goals were (1) to assess the relative importance of chronic warming (with field greenhouses) and increased N and P availability (by fertilization) in controlling gross ecosystem photosynthesis, ecosystem respiration, and ultimately ecosystem C balance; and (2) to attempt to partition ecosystem responses to these treatments between plant and soil contributions. The authors present results of the effects of these manipulations on whole-system CO{sub 2} exchange over seasonal and duel cycles, and on nonrhizosphere soil microbial respiration using in situ soil incubations.

  15. Plant Sterols as Anticancer Nutrients: Evidence for Their Role in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Bruce J. Grattan

    2013-01-01

    Full Text Available While many factors are involved in the etiology of cancer, it has been clearly established that diet significantly impacts one’s risk for this disease. More recently, specific food components have been identified which are uniquely beneficial in mitigating the risk of specific cancer subtypes. Plant sterols are well known for their effects on blood cholesterol levels, however research into their potential role in mitigating cancer risk remains in its infancy. As outlined in this review, the cholesterol modulating actions of plant sterols may overlap with their anti-cancer actions. Breast cancer is the most common malignancy affecting women and there remains a need for effective adjuvant therapies for this disease, for which plant sterols may play a distinctive role.

  16. Moss cushions facilitate water and nutrient supply for plant species on bare limestone pavements

    DEFF Research Database (Denmark)

    Jensen, Kaj Sand; Hammer, Kathrine

    2012-01-01

    Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species...... richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates...... under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm(2) cushions with water available for 6 and 10 days during...

  17. Seasonal variation of nutrients leaves concentration of banana plants in Vale do Ribeira-SPVariação sazonal da concentração de nutrientes em folhas de bananeiras, no Vale do Ribeira-SP

    Directory of Open Access Journals (Sweden)

    José Carlos de Mendonça

    2012-08-01

    Full Text Available The Vale do Ribeira, SP, main agricultural activity is the banana crop, which accounts for most of this fruit production in the State of São Paulo. The nutritional balance of the plant is one of the most important factors for the banana plant can complete the cycle and achieve high productivity. Aiming to evaluate the seasonal variation of leaf nutrient concentration in banana plants in Vale do Ribeira-SP, we used the results of 252 chemical analyses of plant tissue, collected from August 2009 to September 2010, in the 18 representative properties for the region, ten cultivated with subgroup Cavendish banana plant and eight of subgroup Prata banana plant. The largest variation between the macronutrient occurred for K and S, and among the micronutrients, especially for Fe and B. In some dates of evaluation, there was a higher leaf concentration of P, K, Ca and Zn, in subgroup Cavendish banana plants, while the subgroup Prata banana plants showed higher leaf concentration, especially of Mn, B and N. Climatic conditions, especially rain, influenced the leaf nutrient content, especially for K, N, S, B and Fe. O Vale do Ribeira, SP, tem como principal atividade agropecuária o cultivo da bananeira, sendo responsável pela maior parte da produção dessa frutífera no estado de São Paulo. O equilíbrio nutricional da planta é um dos fatores mais importantes para que esta consiga completar o ciclo e alcançar alta produtividade. Com o objetivo de avaliar a variação sazonal da concentração foliar de nutrientes em bananeiras cultivadas no Vale do Ribeira-SP, foram utilizados 252 resultados de análise química de nutrientes do tecido vegetal, coletados no período de agosto de 2009 a setembro de 2010, de 18 propriedades representativas na região, dez cultivadas com bananeira do subgrupo Cavendish e oito do subgrupo Prata. A maior variação entre os macronutrientes ocorreu para o K e o S e entre os micronutrientes, principalmente, para o Fe e o B

  18. [Combination of phosphorus solubilizing and mobilizing fungi with phosphate rocks and volcanic materials to promote plant growth of lettuce (Lactuca sativa L.)].

    Science.gov (United States)

    Velázquez, María S; Cabello, Marta N; Elíades, Lorena A; Russo, María L; Allegrucci, Natalia; Schalamuk, Santiago

    2017-09-08

    Arbuscular mycorrhizal fungi (AMF) increase the uptake of soluble phosphates, while phosphorus solubilizing fungi (S) promote solubilization of insoluble phosphates complexes, favoring plant nutrition. Another alternative to maintaining crop productivity is to combine minerals and rocks that provide nutrients and other desirable properties. The aim of this work was to combine AMF and S with pyroclastic materials (ashes and pumices) from Puyehue volcano and phosphate rocks (PR) from Rio Chico Group (Chubut) - to formulate a substrate for the production of potted Lactuca sativa. A mixture of Terrafertil®:ashes was used as substrate. Penicillium thomii was the solubilizing fungus and Rhizophagus intraradices spores (AMF) was the P mobilizer (AEGIS® Irriga). The treatments were: 1) Substrate; 2) Substrate+AMF; 3) Substrate+S; 4) Substrate+AMF+S; 5) Substrate: PR; 6) Substrate: PR+AMF; 7) Substrate: PR+S and 8) Substrate: PR+AMF+S. Three replicates were performed per treatment. All parameters evaluated (total and assimilable P content in substrate, P in plant tissue and plant dry biomass) were significantly higher in plants grown in substrate containing PR and inoculas with S and AMF. This work confirms that the combination of S/AMF with Puyehue volcanic ashes, PR from the Río Chico Group and a commercial substrate promote the growth of L. sativa, thus increasing the added value of national geomaterials. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Effect of iron stress on Withania somnifera L.: antioxidant enzyme response and nutrient elemental uptake of in vitro grown plants.

    Science.gov (United States)

    Rout, Jyoti Ranjan; Behera, Sadhana; Keshari, Nitin; Ram, Shidharth Sankar; Bhar, Subhajit; Chakraborty, Anindita; Sudarshan, Mathummal; Sahoo, Santi Lata

    2015-03-01

    In the present study the response of antioxidant enzyme activities and the level of expression of their corresponding genes on bioaccumulation of iron (Fe) were investigated. In vitro germinated Withania somnifera L. were grown in Murashige and Skoog's liquid medium with increasing concentrations (0, 25, 50, 100 and 200 µM) of FeSO4 for 7 and 14 days. Root and leaf tissues analyzed for catalase (CAT, EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1) and guaiacol peroxidase (GPX, EC 1.11.1.7), have shown an increase in content with respect to exposure time. Isoforms of CAT, SOD and GPX were separated using non-denaturing polyacrylamide gel electrophoresis and observed that the isoenzymes were greatly affected by higher concentrations of Fe. Reverse transcriptase polymerase chain reaction analysis performed by taking three pairs of genes of CAT (RsCat, Catalase1, Cat1) and SOD (SodCp, TaSOD1.2, MnSOD) to find out the differential expression of antioxidant genes under Fe excess. RsCat from CAT and MnSOD from SOD have exhibited high levels of gene expression under Fe stress, which was consistent with the changes of the activity assayed in solution after 7 days of treatment. Analysis by proton induced X-ray emission exhibited an increasing uptake of Fe in plants by suppressing and expressing of other nutrient elements. The results of the present study suggest that higher concentration of Fe causes disturbance in nutrient balance and induces oxidative stress in plant.

  20. Absorção de nutrientes pelo tomateiro cultivado sob condições de campo e de ambiente protegido Nutrient absorption by tomato plants grown under field and protected conditions

    Directory of Open Access Journals (Sweden)

    Jamil Abdalla Fayad

    2002-03-01

    Full Text Available Foram realizados dois experimentos, na Universidade Federal de Viçosa, objetivando caracterizar a absorção de nutrientes pelo tomateiro cultivado sob condições de campo e de ambiente protegido. O primeiro, com a cultivar Santa Clara, cultivada a campo, no sistema de cerca cruzada e sete cachos. O segundo, em estufa plástica, com o híbrido EF-50, conduzidas verticalmente, mantendo-se oito cachos em cada uma. Ambos experimentos foram delineados em blocos ao acaso, com quatro repetições. O primeiro constituído por oito e o segundo por nove tratamentos. Em ambos experimentos, o padrão de absorção de nutrientes seguiu o acúmulo de matéria seca pelas plantas. No experimento de campo, a ordem decrescente de acúmulo de nutrientes na parte aérea foi: K, N, Ca, S, P, Mg, Cu, Mn, Fe e Zn, alcançando os valores máximos de 360; 206; 202; 49; 32; 29 kg.ha-1; 3.415; 2.173; 1.967 e 500 g.ha-1, respectivamente. Em ambiente protegido, o acúmulo de nutrientes na parte aérea do tomateiro decresceu na seguinte ordem: K, N, Ca, S, Mg, P, Mn, Fe; Cu e Zn, alcançando os valores de 264; 211; 195; 49; 40; 30 kg.ha-1; 3.200; 2.100; 1.600 e 700 g.ha-1, respectivamente. As taxas de absorção diária dos nutrientes são apresentadas bem como as porcentagens de absorção do N e de K em determinados períodos do crescimento do tomateiro, visando auxiliar na programação das épocas de aplicação destes nutrientes em cobertura.Two experiments were conducted at Universidade Federal de Viçosa to evaluate nutrient absortion by tomato plants grown under field and protected conditions. In the first experiment, tomato cv. Santa Clara was grown in the field with seven clusters/plant. In the second one tomato hybrid EF-50 was grown in plastic greenhouse and pruned to eight clusters. Both experiments were designed as randomized blocks, with four replicates. The first and second experiments were performed with eight and nine treatments, respectively. In both

  1. Nutrients in the cassava (Manihot esculenta Crantz leaf meal at three ages of the plant Nutrientes na farinha de folhas de mandioca (Manihot esculenta Crantz em três idades da planta

    Directory of Open Access Journals (Sweden)

    Carmen Wobeto

    2006-12-01

    Full Text Available The high number of cassava cultivars adapted to many different regions provides a wide variation in the chemical composition of cassava leaves meal (CLM. Therefore, the contents of some nutrients in CLM from five cultivars at three ages of the plant were investigated in order to select the cultivars and ages with superior levels of these nutrients. When the plants were 12 months old, the highest levels of crude protein (CP, beta-carotene, iron, magnesium, phosphorus and sulfur were observed. The IAC 289-70 cv. showed the highest levels of magnesium, as well as considerable contents of CP, beta-carotene, iron, zinc and sulfur, which did not differ statistically from the cultivars showing the highest levels of these nutrients.O número elevado de cultivares de mandioca adaptados às mais diversas regiões confere ampla variação na composição química da farinha de folhas de mandioca (FFM. Portanto, foram investigados os teores de alguns nutrientes nas FFM de cinco cultivares em três idades da planta, a fim de selecionar cultivares e idades com níveis superiores destes nutrientes. Aos 12 meses de idade da planta, observaram-se os maiores níveis de proteína bruta (PB, beta-caroteno, ferro, magnésio, fósforo e enxofre. O cultivar IAC 289-70 apresentou os maiores níveis de magnésio, assim como teores apreciáveis de PB, beta-caroteno, ferro, zinco e enxofre, pois não diferiu estatisticamente dos cultivares com os níveis mais elevados destes nutrientes.

  2. Kinetic start-up performance of two large treatment plants for nutrient removal

    DEFF Research Database (Denmark)

    Haarbo, A.; Harremoës, Poul; Thirsing, C.

    2001-01-01

    . For more than 8 years an extensive effort has been made to determine an optimum solution for this upgrading from a technical and financial point of view. The work included six years of comprehensive pilot plant investigations with the aim of thoroughly studying and interpreting the kinetics...

  3. The contribution of plant uptake to nutrient removal by floating treatment wetlands

    NARCIS (Netherlands)

    Keizer-Vlek, H.E.; Verdonschot, P.F.M.; Verdonschot, R.C.M.; Dekkers, T.B.M.

    2014-01-01

    Floating treatment wetlands (FTWs) may provide an appealing alternative to the more conventional (sub) surface flow wetlands to solve problems associated with eutrophication in urban surface waters, because they do not claim additional land area. This study examined the contribution of plant uptake

  4. The contribution of plant uptake to nutrient removal by floating treatment wetlands

    NARCIS (Netherlands)

    Keizer-Vlek, H.E.; Verdonschot, P.F.M.; Verdonschot, R.C.M.; Dekkers, T.B.M.

    2014-01-01

    Floating treatment wetlands (FTWs) may provide an appealing alternative to the more conventional (sub) surface flow wetlands to solve problems associated with eutrophication in urban surface waters, because they do not claim additional land area. This study examined the contribution of plant uptake

  5. Dissimilar response of plant and soil biota communities to long-term nutrient adition in grasslands

    NARCIS (Netherlands)

    Wal, van der A.; Geerts, R.H.E.M.; Korevaar, H.; Schouten, A.J.; Jagers op Akkerhuis, G.A.J.M.; Rutgers, M.; Mulder, C.

    2009-01-01

    The long-term effect of fertilizers on plant diversity and productivity is well known, but long-term effects on soil biota communities have received relatively little attention. Here, we used an exceptional long-lasting (>40 years) grassland fertilization experiment to investigate the long-term e

  6. Phytoremediation of nutrient polluted stormwater runoff: water hyacinth as a model plant

    NARCIS (Netherlands)

    Fox, L.J.

    2009-01-01

    Het doel van het in dit proefschrift beschreven onderzoek was om te verkennen in hoeverre fytoremediatie met behulp van waterplanten kon beheersen en de waterkwaliteit te verbeterenPhytoremediation of nutriënt polluted stormwater runoff using water hyacinth as a model plant was explored in greenhous

  7. Interactions between plants and soil nutrient cycling under elevated CO2

    NARCIS (Netherlands)

    Graaff, de M.A.

    2007-01-01

    The atmospheric concentration of the greenhouse gas CO2 is rising and may stimulate plant production and soil C input. If soil C input rates exceed soil C respiration rates under elevated CO2, global warming may be mitigated by long-term soil C sequestration. However, whether s

  8. Mobilization

    Science.gov (United States)

    1987-01-01

    istic and romantic emotionalism that typifies this genre. Longino, James C., et al. “A Study of World War Procurement and Industrial Mobilization...States. Harrisburg, PA: Military Service Publishing Co., 1941. CARL 355.22 J72b. Written in rough prose , this World War II era document explains the

  9. Guidance for Deployment of Mobile Technologies for Nuclear Power Plant Field Workers

    Energy Technology Data Exchange (ETDEWEB)

    Heather D. Medema; Ronald K. Farris

    2012-09-01

    This report is a guidance document prepared for the benefit of commercial nuclear power plants’ (NPPs) supporting organizations and personnel who are considering or undertaking deployment of mobile technology for the purpose of improving human performance and plant status control (PSC) for field workers in an NPP setting. This document especially is directed at NPP business managers, Electric Power Research Institute, Institute of Nuclear Power Operations, and other non-Information Technology personnel. This information is not intended to replace basic project management practices or reiterate these processes, but is to support decision-making, planning, and preparation of a business case.

  10. Synergistic effects of light quality, carbon dioxide and nutrients on metabolite compositions of head lettuce under artificial growth conditions mimicking a plant factory.

    Science.gov (United States)

    Miyagi, Atsuko; Uchimiya, Hirofumi; Kawai-Yamada, Maki

    2017-03-01

    Carbon dioxide (CO2), nutrient supply, and light quality are amongst the major controlling factors to improve the biomass production and nutritional outputs in plant factory. The present study employed CE-MS to investigate the effects of high CO2, nutrient formulation, and LED on the accumulation of primary metabolites in head lettuce. Results suggested that high CO2 (1000ppm) and nutrient supply enhanced both the biomass and some amino acids. Hierarchical clustering analysis was used to evaluate effects of red LED in combination with high CO2 and Hoagland's formulation; distinctive cluster formation contained 14 amino acids (mostly branched-chain and aromatic amino acids, histidine and arginine). Thus, simultaneous treatments of monochromatic LED, high CO2 and nutrient formulation improved the amino acids accumulation, and likely reduced the inorganic nitrogen sources in planta.

  11. Thermal treatment and leaching of biochar alleviates plant growth inhibition from mobile organic compounds

    Directory of Open Access Journals (Sweden)

    Nigel V. Gale

    2016-08-01

    Full Text Available Recent meta-analyses of plant responses to biochar boast positive average effects of between 10 and 40%. Plant responses, however, vary greatly across systems, and null or negative biochar effects are increasingly reported. The mechanisms responsible for such responses remain unclear. In a glasshouse experiment we tested the effects of three forestry residue wood biochars, applied at five dosages (0, 5, 10, 20, and 50 t/ha to a temperate forest drystic cambisol as direct surface applications and as complete soil mixes on the herbaceous pioneers Lolium multiflorum and Trifolium repens. Null and negative effects of biochar on growth were found in most cases. One potential cause for null and negative plant responses to biochar is plant exposure to mobile compounds produced during pyrolysis that leach or evolve following additions of biochars to soil. In a second glasshouse experiment we examined the effects of simple leaching and heating techniques to ameliorate potentially phytotoxic effects of volatile and leachable compounds released from biochar. We used Solid Phase Microextraction (SPME–gas chromatography–mass spectrometry (GC-MS to qualitatively describe organic compounds in both biochar (through headspace extraction, and in the water leachates (through direct injection. Convection heating and water leaching of biochar prior to application alleviated growth inhibition. Additionally, growth was inhibited when filtrate from water-leached biochar was applied following germination. SPME-GC-MS detected primarily short-chained carboxylic acids and phenolics in both the leachates and solid chars, with relatively high concentrations of several known phytotoxic compounds including acetic acid, butyric acid, 2,4-di-tert-butylphenol and benzoic acid. We speculate that variable plant responses to phytotoxic organic compounds leached from biochars may largely explain negative plant growth responses and also account for strongly species

  12. Rhizosphere priming: a nutrient perspective.

    Science.gov (United States)

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

    2013-01-01

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

  13. Nutrient and heavy metal accumulation in municipal organic waste from separate collection during anaerobic digestion in a two-stage laboratory biogas plant.

    Science.gov (United States)

    Knoop, Christine; Dornack, Christina; Raab, Thomas

    2017-09-01

    Municipal organic waste (MOW) is a promising feedstock for biogas plants and separate collection will increase available quantities. To close nutrient circles digestates shall be redistributed to arable land. However, less is known about digestate properties and how they are influenced during digestion. Therefore, changes in nutrient and heavy metal concentration in the solid digestate were investigated during anaerobic treatment of MOW in a two-stage laboratory biogas plant. Results show that the solid digestate is exposed to element accumulation, except for N, P and Mg. The loss of initial N, P and Mg load accounts up to 45%, which must be redistributed elsewhere in the digester system. K load of feedstock was completely rediscovered in the solid digestate. Heavy metal concentration in the digestate increases by factor 1.6 at average. The results emphasize that element retention in the digester system has a decisive impact on nutrient content of digestates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Biomass production and control of nutrient leaching of willows using different planting methods with special emphasis on an appraisal of the electrical impedance for roots

    Energy Technology Data Exchange (ETDEWEB)

    Yang Cao

    2011-07-01

    Willow reproduction can be achieved through vertically or horizontally planted cuttings. Conventionally, plantations are established by inserting cuttings vertically into the soil. There is, however, a lack of information about the biomass production and nutrient leaching of plantations established through horizontally planted cuttings. A greenhouse experiment and a field trial were carried out to investigate whether horizontally planted Salix schwerinii cuttings have a positive effect on stem yield, root distribution and nutrient leaching in comparison with vertically planted cuttings with different planting densities. The shoots' height of horizontally planted cuttings was significantly smaller than that of vertically planted cuttings during the first two weeks after planting in the pot experiment. Thereafter, no significant effect of planting orientation on the stem biomass was observed in the two conducted experiments. In both experiments the total stem biomass increased with the planting density. It was also found that the fine root biomass and the specific root length were not affected by the planting orientation or density, while the fine root surface area and the absorbing root surface area (ARSA) were affected only by the planting density. The planting orientation did not affect the nutrient concentrations in the soil leachate, apart from SO{sub 4}-S and PO{sub 4}-P in the pot experiment. The ARSA in the pot experiment was assessed by using the earth impedance method. The applicability of this method was evaluated in a hydroponic study of willow cuttings where root and stem were measured independently. Electrical resistance had a good correlation with the contact area of the roots with the solution. However, the resistance depended strongly on the contact area of the stem with the solution, which caused a bias in the evaluation of root surface area. A similar experimental set-up with electrical impedance spectroscopy was employed to study the

  15. Nutrient Status in Composts and Changes in Radioactive Cesium Following the Fukushima Daiichi Nuclear Power Plant Accident

    Directory of Open Access Journals (Sweden)

    Dikkumburage Jasintha Jayasanka

    2016-12-01

    Full Text Available Following the Fukushima Daiichi Nuclear Power Plant (FDNPP accident, the forests in the Fukushima area were highly contaminated with radiocesium (137Cs and 134Cs. Therefore, there is a need to develop strategies for remediation of the contaminated forests. We assessed changes in radioactive cesium (134Cs and 137Cs contamination and nutrient status in composts derived from wood chip, bamboo leaf and bamboo powder using rice bran and wheat meal as sub-materials. Changes in soil properties and Komatsuna (Brassica rapa var. perviridis growth were also investigated due the application of composts and initial materials at 0, 2.5, 5 and 10 kg·m−2 input levels. Mixing of sub-materials significantly reduced the concentration of radioactive Cs and improved compost quality. The effectiveness of three composts on soil quality improvement varied depending on their types and rates of applications. Amendments of bamboo leaf composts at 10 kg·m−2 resulted in the significantly highest soil inorganic N, available P and exchangeable K contents. Amendments of final composts also enhanced Komatsuna growth. Furthermore, radioactive Cs contaminations of the Komatsuna plants grown in these composts were below 0.1 Bq·kg−1. This study may help to remediate the forests contaminated with radiocesium in the Fukushima area while improving the soil organic matter content to enhance soil sustainability.

  16. Human urine and wood ash as plant nutrients for red beet (Beta vulgaris) cultivation: impacts on yield quality.

    Science.gov (United States)

    Pradhan, Surendra K; Holopainen, Jarmo K; Weisell, Janne; Heinonen-Tanski, Helvi

    2010-02-10

    The objective of this study was to evaluate the effect of human urine and wood ash fertilization on the yield and quality of red beet by measuring the microbial, nutrient, and antioxidant (betanin) content of the roots. Red beets were fertilized with 133 kg of N/ha as mineral fertilizer, urine and ash, and only urine with no fertilizer as a control. The mineral-fertilized plants and urine- and ash-fertilized plants also received 89 kg of P/ha. Urine and ash and only urine fertilizer produced 1720 and 656 kg/ha more root biomass, respectively, versus what was obtained from the mineral fertilizer. Few fecal coliforms and coliphage were detected in mineral-fertilized and urine- and ash-fertilized red beet roots. The protein and betanin contents in red beet roots were similar in all treatments. In conclusion, this study revealed that urine with or without ash can increase the yield of red beet and furthermore the microbial quality and chemical quality were similar to the situation in mineral-fertilized products.

  17. The effect of intra- and inter-regional labour mobility on plant performance in Denmark: the significance of related labour inflows

    NARCIS (Netherlands)

    Timmermans, B.; Boschma, R.

    2013-01-01

    This article investigates the impact of labour mobility on plant performance in Denmark. Our study shows that the effect of labour mobility can only be assessed when one accounts for the type of skills that flow into the plant and the degree to which these match the existing skills at the plant leve

  18. The effect of intra- and inter-regional labour mobility on plant performance in Denmark : The significance of related labour inflows

    NARCIS (Netherlands)

    Timmermans, Bram; Boschma, Ron

    2014-01-01

    This article investigates the impact of labour mobility on plant performance in Denmark. Our study shows that the effect of labour mobility can only be assessed when one accounts for the type of skills that flow into the plant and the degree to which these match the existing skills at the plant leve

  19. Density and composition of microorganisms during long-term (418 day) growth of potato using biologically reclaimed nutrients from inedible plant biomass

    Science.gov (United States)

    Garland, J. L.; Cook, K. L.; Johnson, M.; Sumner, R.; Fields, N.

    1997-01-01

    A study evaluating alternative methods for long term operation of biomass production systems was recently completed at the Kennedy Space Center (KSC). The 418-day study evaluated repeated batch versus mixed-aged production of potato grown on either standard 1/2-strength Hoagland's nutrient solution or solutions including nutrients recycled from inedible plant material. The long term effects of closure and recycling on microbial dynamics were evaluated by monitoring the microbial communities associated with various habitats within the plant growth system (i.e., plant roots, nutrient solution, biofilms within the hydroponic systems, atmosphere, and atmospheric condensate). Plate count methods were used to enumerate and characterize microorganisms. Microscopic staining methods were used to estimate total cell densities. The primary finding was that the density and composition of microbial communities associated with controlled environmental plant growth systems are stable during long term operation. Continuous production resulted in slightly greater stability. Nutrient recycling, despite the addition of soluble organic material from the waste processing system, did not significantly increase microbial density in any of the habitats.

  20. In search for key biogeochemical factors for the conservation of plant species of acidic nutrient-poor habitats: comparing growth sites of common and endangered species

    NARCIS (Netherlands)

    Kleijn, D.; Bekker, R.M.; Bobbink, R.; Graaf, de M.C.C.; Roelofs, J.G.M.

    2008-01-01

    Summary During the last century, many plant species typical of heathland and nutrient-poor acidic grasslands have become rare whereas others have remained common. Habitat restoration often fails to enhance the rare species, which may in part be caused by the failure to restore the biogeochemical con

  1. Plant a Tree, Save a Lake: Urban trees reduce groundwater nutrient pollution

    Science.gov (United States)

    Nidzgorski, D. A.; Hobbie, S. E.

    2013-12-01

    Background/Questions/Methods Urban trees are known to enhance human well-being in many ways, from improving air quality to reducing crime rates, but less is understood about how urban trees can affect the water quality of local lakes and streams. Many urban waterways suffer from excess nitrogen (N) and phosphorus (P) feeding algal blooms, which cause lower water clarity and oxygen levels, bad odor and taste, and the loss of desirable species. The expansion and turnover of urban forests present a large-scale opportunity for homeowners, city foresters, and other land managers to select species that reduce nutrient pollution and improve the water quality and ecosystem service provisioning of local waterways. In this study, we examine how common urban tree species affect N and P leaching to groundwater. We sampled thirty-three trees of fourteen species, and seven open grassy areas, across three city parks in Saint Paul, Minnesota. We installed lysimeters at 60cm depth to collect soil water and measure nutrient concentrations approximately biweekly. We collected soil samples from 0-10cm, 10-20cm, 20-40cm, and 40-60cm as well as leaf, root, and leaf-litter samples, for carbon, nitrogen, and phosphorus analyses. Results/Conclusions A prolonged drought in 2011-2012 prevented lysimeter sampling during autumn litterfall and snowmelt to date. Nevertheless, data from July-August 2011, April-June 2012, and May-June 2013 showed significant differences in total N and P concentrations in lysimeter water among grass, conifer, and hardwood sites, with trees reducing concentrations relative to turfgrass and hardwoods reducing them relative to conifers (TN mg/L×se: grass=8.3×1.3, conifer = 7.3×1.0, hardwood=5.0×0.7; p=0.0002; TP μg/L×se: grass=153.2×21.4, conifer=82.5×14.0, hardwood=46.0×4.0; p=0.0001). Total P concentrations in lysimeter water were significantly higher than expected for most soils, with a grand mean of 78μg/L, higher than the lake-eutrophication standard of

  2. Heavy metal and nutrient concentration in soil and plants growing on a metalliferous chromite minespoil.

    Science.gov (United States)

    Samantaray, S; Rout, G R; Das, P

    2001-10-01

    Metal contamination in soil and plant samples from a chromite mine and its adjoining regions was determined. The metal concentration varied in stem, leaf and root of different tree species. In the case of shrubs, the highest concentration of iron (18.5 mg kg(-1) was detected in the stem of Combretum roxburghii. The concentration of aluminium varied from 1.8 - 5.3 mg kg(-1) dry weight, whereas the nickel content was found to be the highest in the stem of Calotropis gigantea. In the case of herbs, chromium concentration was highest (60.9 mg kg(-1) dry weight) in Evovulus alsenoides and the lowest (18.8 mg kg(-1) dry weight) in Andrographis paniculata. There was a significant correlation observed between chromium in soil with the root of tree species like Lagerstroemia parviflora, Madhuca longifolia, Anogeissus latifolia and Haldina cordyfolia. Nickel in soil was significantly correlated with the stem and leaf of all the tree species except Chlroxylon sweitenta. Iron in soil showed correlation with the stem and leaf of Chloroxylon sweitenia. Among the shrubs (Calotropis gigantea, Combretum roxburghii and Smilax zeylancia), chromium in soil showed a correlation with the root. Nickel in soil was positively correlated with the stem and leaf of Calotropis gigantea and Combretum roxburghii. Among the herbs, chromium in the whole plant of Evolvulus alsenoids, Solanum surattense and Phyllanthus fraternus showed significant positive correlation with soil; nickel in Solanum surattense showed significant positive correlation with soil. The positive correlation coefficient was observed between iron in the whole plant and soil on Phyllanthus virgatus, Phyllanthus fraternus and Andrographis paniculata. The above information would be useful for the establishment of a vegetation cover on the minewaste heaps.

  3. The influence of earthworms on the mobility of microelements in soil and their availability for plants

    Science.gov (United States)

    Bityutskii, N. P.; Kaidun, P. I.

    2008-12-01

    The influence of earthworms ( Aporrectodea caliginosa, Lumbricus rubellus, L. terrestris, and Eisenia fetida) on the mobility of microelements and their availability for plants was studied. The contents of water-soluble Fe and Mn compounds extracted from the coprolites were 5-10 times higher than that in the soil (enriched in calcium carbonate and dried) consumed by the earthworms. This digestion-induced effect became higher with the age of the coprolites (up to 9 days) and took place under their alkalization. In the excreta (surface + enteric) of earthworms, the Fe concentration exceeded those of Mn and Zn by many times. Iron and manganese were mostly concentrated (>80% and >60%, respectively) in the organic part of the excrements. In the tests with hydroponics, the excreta were found to be a source of iron compounds available for plants that were similar to Fe2(SO4)3 or Fe-citrate by their physiological effect in the case when the Fe concentration in the excretions was above 0.7 μM. However, the single application of excreta of different earthworm species into the CaCO3 enriched soil did not significantly affect the plant (cucumber) nutrition. The analysis of the transport of microelements with xylem sap showed that this fact appeared to be due to the absence of an Fe deficit in the cucumber plants because of their high capability for the absorption of weakly soluble iron compounds.

  4. Influence of effluents from a Wastewater Treatment Plant on nutrient distribution in a coastal creek from southern Brazil

    Directory of Open Access Journals (Sweden)

    Isaac Rodrigues Santos

    2008-02-01

    Full Text Available The hypothesis that effluents treated through activated sludge process cause changes in nutrient biogeochemistry of receiving water bodies was investigated in Vieira creek, southern Brazil. Dissolved oxygen, suspended matter, and pH did not vary among the sampling stations. Nutrient, biochemical oxygen demand, and conductivity values were significantly higher downstream from the Wastewater Treatment Plant (WWTP effluents. Further downstream, nitrate concentrations were higher due to ammonium nitrification, organic matter remineralization and/or the occurrence of unidentified sources. Per capita nutrient emission factors were estimated to be 0.16 kg P.yr-1 and 4.14 kg N.yr-1. Under pristine conditions, low N:P ratios were observed, which were significantly increased downstream due to the high ammonium input. The mixing zone of the nitrogen-rich waters from Vieira creek with the phosphorus-enriched waters from Patos lagoon estuary was considered under high risk of eutrophication. The results could be useful for planning and management of WWTP-effluent receiving waters in temperate regions from developing countries.A hipótese de que efluentes urbanos tratados através de um sistema de lodo ativado causam alterações na qualidade de água de ambientes aquáticos foi investigada no Arroio Vieira, Rio Grande, RS. Amostras de água foram coletadas a montante e a jusante dos emissários de uma estação de tratamento de esgoto (ETE. Oxigênio, material em suspensão e pH não variaram espacialmente. Já os valores para os nutrientes e para a demanda bioquímica do oxigênio foram significativamente maiores a jusante dos efluentes. Mais a jusante, as concentrações de nitrato aumentam devido à nitrificação do nitrogênio amoniacal, remineralização da matéria orgânica e/ou ocorrência de outros aportes não-identificados. A emissão de nutrientes per capita após o tratamento dos efluentes domésticos (0.16 kg P ano-1 e 4.14 kg N ano-1

  5. Symbiotic fungi that are essential for plant nutrient uptake investigated with NMP

    Energy Technology Data Exchange (ETDEWEB)

    Pallon, J. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden)]. E-mail: Jan.Pallon@nuclear.lu.se; Wallander, H. [Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund (Sweden); Hammer, E. [Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund (Sweden); Arteaga Marrero, N. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Auzelyte, V. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Elfman, M. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Kristiansson, P. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Nilsson, C. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Olsson, P.A. [Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund (Sweden); Wegden, M. [Division of Nuclear Physics, Department of Physics, Lund Institute of Technology, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden)

    2007-07-15

    The nuclear microprobe (NMP) technique using PIXE for elemental analysis and STIM on/off axis for parallel mass density normalization has proven successful to investigate possible interactions between minerals and ectomycorrhizal (EM) mycelia that form symbiotic associations with forest trees. The ability for the EM to make elements biologically available from minerals and soil were compared in field studies and in laboratory experiments, and molecular analysis (PCR-RFLP) was used to identify ectomycorrhizal species from the field samplings. EM rhizomorphs associated with apatite in laboratory systems and in mesh bags incubated in forest ecosystems contained larger amounts of Ca than similar rhizomorphs connected to acid-washed sand. EM mycelium produced in mesh bags had a capacity to mobilize P from apatite-amended sand and a high concentration of K in some rhizomorphs suggests that these fungi are good accumulators of K and may have a significant role in transporting K to trees. Spores formed by arbuscular mycorrhizal (AM) fungi in laboratory cultures were compared with spores formed in saline soils in Tunisia in Northern Africa. We found lower concentrations of P and higher concentrations of Cl in the spores collected from the field than in the spores collected from laboratory cultures. For the case of laboratory cultures, the distribution of e.g. P and K was found to be clearly correlated.

  6. A new method for antimony speciation in plant biomass and nutrient media using anion exchange cartridge.

    Science.gov (United States)

    Tisarum, Rujira; Ren, Jing-Hua; Dong, Xiaoling; Chen, Hao; Lessl, Jason T; Ma, Lena Q

    2015-11-01

    A selective separation method based on anion exchange cartridge was developed to determine antimony (Sb) speciation in biological matrices by graphite furnace atomic absorption spectrophotometry (GFAAS). The selectivity of the cartridge towards antimonite [Sb(III)] and antimonate [Sb(V)] reversed in the presence of deionized (DI) water and 2mM citric acid. While Sb(V) was retained by the cartridge in DI water, Sb(III) was retained in citric acid media. At pH 6, Sb(III) and Sb(V) formed Sb(III)- and Sb(V)-citrate complexes, but the cartridge had higher affinity towards the Sb(III)-citrate complex. Separation of Sb(III) was tested at various concentrations in fresh and spent growth media and plant tissues. Our results showed that cartridge-based Sb speciation was successful in plant tissues, which was confirmed by HPLC-ICP-MS. The cartridge retained Sb(III) and showed 92-104% Sb(V) recovery from arsenic hyperaccumulator Pteris vittata roots treated with Sb(III) and Sb(V). The cartridge procedure is an effective alternative for Sb speciation, offering low cost, reproducible results, and simple Sb analysis using GFAAS.

  7. Rochas silicáticas portadoras de potássio como fontes do nutriente para as plantas solo Potassium-rich silicate rocks as plant nutrient sources

    Directory of Open Access Journals (Sweden)

    Luciano da Silva Ribeiro

    2010-06-01

    Full Text Available O objetivo deste trabalho foi avaliar, em casa de vegetação, o efeito da aplicação de pó de rochas silicáticas portadoras de K (ultramáfica alcalina, brecha piroclástica e flogopitito na liberação de K e sobre outros atributos químicos do solo. Foi utilizado um Latossolo Amarelo distrófico coeso com teor de K de 0,03 cmol c dm-3 de solo. As rochas foram testadas sem e com correção da acidez do solo - neste caso, elevando o valor da saturação por bases para 70 %. Inicialmente, as rochas e o corretivo de acidez foram aplicados e incorporados aos solos de cada vaso com 3 kg de solo, deixando-os em incubação por um período de 45 dias, com a umidade em torno de 80 % da capacidade de campo. Foram testadas as doses equivalentes a 75, 150, 225 e 300 kg ha-1 K2O de todas as rochas e do KCl, usado como fonte de referência. Findo o período de incubação, foi realizado um plantio de soja com a finalidade de observar a dissolução das rochas em um ambiente com plantas. As plantas foram colhidas 50 dias depois do plantio. Foram feitas análises do solo após o período de incubação e depois do plantio da soja. As rochas ultramáfica alcalina e brecha piroclástica foram as que mais liberaram K para o solo; a correção da acidez não influenciou o processo de dissolução das rochas.This greenhouse study evaluated the effect of potassium-rich silicate rocks (alkaline ultramaphic, pyroclastic breccia and phlogopite on the release of K and other chemical nutrients of the soil. A Yellow Latossol with 0.03 cmol c dm-3 K soil was used in the study. The rocks were tested at doses of 75, 150, 225 and 300 kg ha-1 K2O with and without lime, applied to increase the soil base saturation (V-value to 70 %. The rock and lime materials were mixed with the soil in the pots, watered to 80 % of the soil field capacity and incubated for 45 days. An additional pot containing soil and KCl, the reference K source, was also incubated. After incubation

  8. Population dynamics of filamentous bacteria identified in Polish full-scale wastewater treatment plants with nutrients removal.

    Science.gov (United States)

    Miłobędzka, A; Muszyński, A

    2015-01-01

    A comprehensive study of the identity and population dynamics of filamentous bacteria in five Polish full-scale municipal wastewater treatment plants (WWTPs) with nutrients removal had been carried out for 2 years. A quantitative culture-independent, molecular method - fluorescence in situ hybridization - was applied to evaluate the structure of different filamentous bacteria populations and their temporal variations. Activated sludge was examined for the abundance of 11 groups of filamentous bacteria. On average, filaments constituted 28% of all bacteria. All samples presented a low diversity of probe-defined filamentous bacteria, usually with significant domination of Chloroflexi (with distinction to types 1851, 0803 and others) and/or Microthrix (14% and 7% of EUBmix, respectively). Haliscomenobacter hydrossis, Mycolata, Skermania piniformis and TM7 were less abundant, whereas Curvibacter, Thiothrix/021N and family Gordonia have not been detected in any of the samples. The tested WWTPs showed similarity among species found and differences in their abundance. The composition of filamentous populations was rather stable in each plant and similar to those found in other European countries. Little differences between plants were shown by multivariate analysis of variance in terms of Chloroflexi and Microthrix. No significant general correlations have been found with Pearson product-moment correlation coefficient and Spearman's rank correlation coefficient. Medium correlation strength between the presence of different filaments was recorded only for Microthrix and Skermania piniformis. Deleterious effect on settling properties of sludge (measured as sludge volume index) was found only for abundance of Microthrix; a strong linear correlation was recorded between them. However, no other correlations with wastewater and operational data were revealed.

  9. Effects of Plant Age and Rock Phosphate on Quality and Nutrient Release of Legume Residue

    Institute of Scientific and Technical Information of China (English)

    I. ABARCHI; ZHANG Zhan-Yu; B. VANLAUWE; GUO Xiang-Ping; WANG Wei-Mu; B. T. I. ONG'OR; D. TIMBELY

    2009-01-01

    An incubation experiment was carried out on plateau and slope fields to investigate the effect of plant age and rock phosphate (RP) on the organic resource (OR) quality and available N and P release of the legume residues, including standing biomass and surface litter. The legumes, Mueuna pruriens (L.) and Lablab purpureus (L.), were treated with or without Togn rock phosphate (RP) and were sampled at 12, 18, 24 and 30 weeks after planting. Results showed that the application of RP significantly affected the P content of the legume residues on the plateau field for the first 18 weeks, but not the other OR quality parameters, nor their N mineralization, or P release parameters. Although application of RPled to higher P contents in both legumes on the plateau field, the P contents were still far below those observed on the slope field. For both species, the biomass age appeared to have a major impact on their N, P, and polyphenol contents, but not on the lignin content. At 24 weeks, both legume N and P contents dropped to about half their values at 12 weeks of age. Residue age also significantly affected N mineralization both with and without RP addition and the net Olsen-P with RP addition. The younger residues generally led to higher N mineralization and net Olsen-P content than the older residues. The best immediate responses to herbaceous legume addition were expected from younger materials, but often at the cost of the total biomass produced and the possibility to produce seeds. The production of seeds, however, could be potentially implemented on a small area of legumes, thus invariably allowing for maturity and seed production.

  10. Overstory structure and soil nutrients effect on plant diversity in unmanaged moist tropical forest

    Science.gov (United States)

    Gautam, Mukesh Kumar; Manhas, Rajesh Kumar; Tripathi, Ashutosh Kumar

    2016-08-01

    Forests with intensive management past are kept unmanaged to restore diversity and ecosystem functioning. Before perpetuating abandonment after protracted restitution, understanding its effect on forest vegetation is desirable. We studied plant diversity and its relation with environmental variables and stand structure in northern Indian unmanaged tropical moist deciduous forest. We hypothesized that post-abandonment species richness would have increased, and the structure of contemporary forest would be heterogeneous. Vegetation structure, composition, and diversity were recorded, in forty 0.1 ha plots selected randomly in four forest ranges. Three soil samples per 0.1 ha were assessed for physicochemistry, fine sand, and clay mineralogy. Contemporary forest had less species richness than pre-abandonment reference period. Fourteen species were recorded as either seedling or sapling, suggesting reappearance or immigration. For most species, regeneration was either absent or impaired. Ordination and multiple regression results showed that exchangeable base cations and phosphorous affected maximum tree diversity and structure variables. Significant correlations between soil moisture and temperature, and shrub layer was observed, besides tree layer correspondence with shrub richness, suggesting that dense overstory resulting from abandonment through its effect on soil conditions, is responsible for dense shrub layer. Herb layer diversity was negatively associated with tree layer and shrub overgrowth (i.e. Mallotus spp.). Protracted abandonment may not reinforce species richness and heterogeneity; perhaps result in high tree and shrub density in moist deciduous forests, which can impede immigrating or reappearing plant species establishment. This can be overcome by density/basal area reduction strategies, albeit for both tree and shrub layer.

  11. Effect of Plant Growth Promoting Rhizobacteria on the Concentration and Uptake of Macro Nutrients by Corn in a Cd-contaminated Calcareous Soil under Drought Stress

    Directory of Open Access Journals (Sweden)

    shahrzad karami

    2017-02-01

    Full Text Available Introduction: Heavy metals such as cadmium (Cd are found naturally in soils, but their amount can be changed by human activities. The study of the uptake and accumulation of heavy metals by plants is done in order to prevent their threats on human and animal’s health.Cadmium is a toxic element for living organisms. Cadmium competes with many of nutrients to be absorbed by the plant and interferes with their biological roles. Water stress affects the cell structure and the food is diverted from its normal metabolic pathway. It also reduces the availability and uptake of nutrients by the plant. One reason for the reduction of plant growth under drought stress is the accumulation of ethylene in plants. There are ways to mitigate the negative effects of drought stress that one of which is the use of Plant Growth Promoting Rhizobacteria(PGPRs to increasing the availability of nutrients. Soil beneficial bacteria play an important role in the biological cycles and have been used to increase plant health and soil fertility over the past few decades.The aim of this study was to investigate theeffect of PGPRson the concentration and uptake of macro nutrients by corn in a Cd-contaminated calcareous soil under drought stress. Materials and Methods: A greenhouse factorial experiment was conducted in a completely randomized design with three replications. The treatments were two levels of bacteria (with and without bacteria, four levels of Cd (5, 10, 20, and 40 mg kg-1, and three levels of drought stress (without stress, 80, and 65% of field capacity. The pots were filled with 3 kg of treated soil. Cd was treated as its sulfate salt in amounts of 5, 10, 20, and 40 mg kg-1. The soil was mixed uniformly with 150 mg N kg-1 as urea, 20 mg P kg-1 as Ca (H2PO42, 5 mg Fe kg-1 as Fe-EDDHA and 10, 10 and 2.5 mg Zn, Mn and Cu kg-1, respectively as their sulfate salt in order to meet plant needs for these nutrients. Six seeds of Zea mays (var. HIDO were planted at

  12. Nutrient budget in ecosystems

    Science.gov (United States)

    Titlyanova, A. A.

    2007-12-01

    Methods to calculate nutrient budgets in forest and grassland ecosystems are analyzed on the basis of a large number of published materials and original data. New estimates of the belowground production in forest ecosystems with due account for the growth of fine roots are suggested. Nutrient retranslocation from senescent plant tissues to growing plant tissues and nutrient leaching from the forest canopy are discussed. The budgets of major nutrients (N, P, K, and Ca) in tundra, forest, and steppe ecosystems are calculated. Nutrient cycles in two forest ecosystems—a coniferous stand dominated by Picea abies and a broad-leaved stand dominated by Quercus robur—are analyzed in detail. It is shown that the more intensive turnover of nutrients in the oak stand is also characterized by a more closed character of the nutrient cycles.

  13. Nutrients, Toxins, and Water in Terrestrial and Aquatic Ecosystems Treated with Sewage Plant Effluents. Final Report of the Upland Recharge Program

    Energy Technology Data Exchange (ETDEWEB)

    Woodwell, G. M.; Ballard, J. T.; Clinton, J.; Pecan, E. V.

    1976-01-01

    The objective of this work was to appraise the capacity of terrestrial and aquatic plant communities for absorbing and retaining nutrients and organic matter in sewage and for releasing ''clean'' water. Experimental systems included a sere representative of the Eastern Deciduous Forest, a timothy field, two Phalaris arundinacea meadows, a freshwater marsh, a pond, and a marsh-pond complex. Sewage of two qualities was applied at the rate of 5 cm per week; one treatment was equivalent to the release from a primary treatment sewage plant, the second to that from a secondary treatment plant. Under normal circumstances, without the addition of water or nutrients in sewage, the flux of nutrients into the groundwater was greatest under the agricultural communities and least under the late successional forest communities. All the terrestrial communities were net sources of most elements. Because the agricultural communities were fertilized and a substantial fraction of the fertilizer applied remained after the first year, the agricultural communities appeared to be net sinks during the first year of the experiment. The highest concentrations of nutrients in the percolate of the untreated communities commonly occurred in the earliest stages of succession. This relationship was especially conspicuous for nitrogen. Phosphorus and iron appeared to be held tightly within most ecosystems.

  14. Impact of root-induced mobilization of zinc on stable Zn isotope variation in the soil-plant system.

    Science.gov (United States)

    Houben, David; Sonnet, Philippe; Tricot, Guillaume; Mattielli, Nadine; Couder, Eléonore; Opfergelt, Sophie

    2014-07-15

    Stable Zn isotopes are increasingly used to trace the source of metal pollution in the environment and to gain a better understanding of the biogeochemical cycle of Zn. In this work, we investigated the effect of plants on Zn isotope fractionation in the soil-plant system of the surface horizon of two Zn-rich Technosols (pH 6.73-7.51, total Zn concentration = 9470-56600 mg kg(-1)). In a column experiment, the presence of Agrostis capillaris L. significantly increased the mobilization of Zn from soil to leachate, predominantly as a result of root-induced soil acidification. The zinc isotope compositions of plants and leachates indicated that the Zn uptake by A. capillaris did not fractionate Zn isotopes as compared to the leachates. Within the plant, heavier Zn isotopes were preferentially retained in roots (Δ66Znroot - shoot=+0.24 to +0.40 ‰). More importantly, the Zn released in leachates due to root-induced mobilization was isotopically heavier than the Zn released in the absence of plants (Δ66Zn=+0.16 to +0.18 ‰). This indicates that the rhizosphere activity of A. capillaris mobilized Zn from another pool than the one that spontaneously releases Zn upon contact with the percolating solution. Mobilization of Zn by the roots might thus exert a stronger influence on the Zn isotope composition in the soil solution than the Zn uptake by the plant. This study highlights the key role of the rhizosphere activity in Zn release in soil and demonstrates that stable Zn isotopes provide a useful proxy for the detection of Zn mobilization in soil-plant systems.

  15. Effect of Glomus mosseae and plant growth promoting rhizomicroorganisms (PGPR's on growth, nutrients and content of secondary metabolites in Begonia malabarica Lam.

    Directory of Open Access Journals (Sweden)

    Thangavel Selvaraj

    2008-10-01

    Full Text Available Begonia malabarica Lam. (Begoniaceae is one of the important medicinal plants whose main secondary metabolites are luteolin, quercetin and β-sitosterol. The leaves are used for the treatment of respiratory tract infections, diarrhoea, blood cancer and skin diseases. A study was undertaken to determine the effect of arbuscular mycorrhizal (AM fungus, Glomus mosseae, and some plant growth promoting rhizomicro-organisms (PGPR's on the growth, biomass, nutrients, and content of secondary metabolites of B. malabarica plant under green house conditions. Various plant growth parameters (total plant biomass, mycorrhizal parameter, shoot and root phosphorus, mineral content (potassium, iron, zinc, and copper, and secondary metabolites (total phenols, ortho-dihydroxy phenols, tannins, flavonoids, and alkaloids were determined and found to vary with different treatments. Among all the treatments, plants inoculated with 'microbial consortium' consisting of Glomus mosseae + Bacillus coagulans + Trichoderma viride performed better than with other treatments or uninoculated control plants. The results of this experiment clearly indicated that inoculation of B. malabarica with G. mosseae along with PGPR's enhanced its growth, biomass yield, nutrients and secondary metabolites.

  16. Effect of calcium carbonate on cadmium and nutrients uptake in tobacco (Nicotiana tabacum L.) planted on contaminated soil.

    Science.gov (United States)

    Zeng, Wei-Ai; Li, Fan; Zhou, Hang; Qin, Xiao-Li; Zou, Zi-Jin; Tian, Tao; Zeng, Min; Liao, Bo-Han

    2016-01-01

    In the present study, calcium carbonate (CaCO3) was applied to Cd-contaminated soil at rates of 0, 0.5 and 1.0 g kg(-1). The effect of CaCO3 on soil pH, organic matter, available Cd, exchangeable Cd and level of major nutrients in a tobacco field and on accumulation of various elements in tobacco plants was determined. The results showed that CaCO3 application significantly increased the pH level, available P and exchangeable Ca but decreased organic matter, available Cd, exchangeable Cd, available heavy metals (Fe, Mn, Zn and Cu) and available K in soil. Additionally, CaCO3 application substantially reduced Cd accumulation in tobacco roots, stems, upper leaves, middle leaves and lower leaves, with maximum decrease of 22.3%, 32.1%, 24.5%, 22.0% and 18.2%, respectively. There were large increase in total Ca and slight increases in total N and K but decrease to varying degrees in total Fe, Cu and Zn due to CaCO3 application. CaCO3 had little effect on total P and Mn levels in tobacco leaves.

  17. Utilization of phosphate rock from Lisina for direct application: release of plant nutrients in the exchange-fertilizer mixtures.

    Science.gov (United States)

    Mihajlović, Marija; Perišić, Nebojša; Pezo, Lato; Stojanović, Mirjana; Milojković, Jelena; Lopičić, Zorica; Petrović, Marija

    2014-10-15

    This study examined the possibility of direct application of phosphate rock (PR) from Lisina deposit, in a mixture with natural clinoptilolite (Cp) and clinoptilolite partially saturated with ammonium ions (NH4-Cp). Solution P concentrations of the NH4-Cp/PR mixtures were sufficient for plant growth and ranged from 0.36 to 0.82 mg L(-1). The median NH4-Cp/PR ratio and the longest proposed mixing time had the most positive impact on the P concentration. Solution Ca concentrations of the NH4-Cp/PR mixtures were between 112.5 and 700.5 mg L(-1), indicating that use of the proposed NH4-Cp/PR mixtures solves the potential lack of Ca(2+) in the solution, which is typical for substrates of similar composition. Selected artificial neural networks (ANNs) were able to predict experimental variables for a broad range of the process parameters all through assay. Manifold effects of small changes in composition of the mixtures and time on the observed concentrations of nutrients were shown using the sensitivity analysis.

  18. Influence of nutrient media on callus induction, somatic embryogenesis and plant regeneration in selected Turkish crocus species.

    Science.gov (United States)

    Verma, Sandeep Kumar; Das, Ashok Kumar; Cingoz, Gunce Sahin; Uslu, Emel; Gurel, Ekrem

    2016-06-01

    Callus induction, somatic embryogenesis and plant regeneration were initiated in selected five species of Turkish crocus using three diffrent explants (leaf, stem and corm) cultured on four different media (MS, GB5, LS and CHE). The highest frequencies of callus induction (100%) and shoot regeneration (70%, with 7.2 shoots/callus) were found in the crocus species Crocus oliveri ssp. Oliveri, using the MS medium containing 5% (w/v) sucrose supplemented with (4 mg/L NAA + 4 mg/L TDZ) and (2 mg/L IAA + 2 mg/L TDZ + 2 mg/L BAP). When the embryogenic calli were transferred into the four nutrient media containing (2 mg/L IAA + 2 mg/L TDZ) and 100 mg/L ABA, these further developed into cotyledonary embryos. Maximum number of somatic embryos (2.9 embryos per leaf explant, with a frequency 46.6%) was obtained in C. oliveri ssp. Oliveri. During subculture using the half strength media, cotyledonary embryos gradually developed into plantlets.

  19. Intercropping of green garlic (Allium sativum L. induces nutrient concentration changes in the soil and plants in continuously cropped cucumber (Cucumis sativus L. in a plastic tunnel.

    Directory of Open Access Journals (Sweden)

    Xuemei Xiao

    Full Text Available A pot-based experiment was conducted to investigate nutrient concentrations in cucumber plants intercropped with various amounts of green garlic. In addition, the soil nutrient contents were studied over two consecutive growing seasons. The results revealed that the accumulation of biomass and the nutritional elements nitrogen (N, phosphorus (P, potassium (K, calcium (Ca and manganese (Mn in cucumber plants were significantly increased for intercropping treatments during the two growing seasons compared to monoculture. Conversely, magnesium (Mg concentrations were decreased in the cucumber plants. Shoot iron (Fe concentrations decreased whereas root Fe concentrations increased in the intercropping system. Shoot and root zinc (Zn concentrations decreased during the fall of 2011 but increased during the spring of 2012. Soil organic matter and available N, P and K were significantly increased as the proportion of intercropped green garlic increasing. Medium levels of intercropping green garlic improved cucumber nutrient concentrations the most. The regression analysis showed that the concentrations of most elements were significantly related to the amounts of garlic bulbs, especially the microelements in the spring 2011. The available soil N and organic matter were linearly related to the amounts of garlic bulbs. The results indicate that the nutritional status of the soil and plants of continuously cropped cucumber could be improved by intercropping with green garlic.

  20. Plant root-driven hydraulic redistribution, root nutrient uptake and carbon exudation interact with soil properties to generate rhizosphere resource hotspots that vary in space and time

    Science.gov (United States)

    Espeleta, J. F.; Neumann, R. B.; Cardon, Z. G.; Mayer, K. U.; Rastetter, E. B.

    2014-12-01

    Hydraulic redistribution (HR) of soil water by plants occurs in seasonally dry ecosystems worldwide. During drought, water flows from deep moist soil, through plant roots, into dry (often litter-rich) upper soil layers. Using modeling, we explored how physical transport processes driven by transpiration and hydraulic redistribution interact with root physiology (nutrient uptake and carbon exudation) and soil properties (soil texture and cation exchange) to influence nitrogen and carbon concentrations in the rhizosphere. At the single root scale, we modeled a 10-cm radial soil domain, and simulated solute transport, soil cation exchange, and root exudation and nutrient uptake under two water flow patterns: daytime transpiration without nighttime HR, and daytime transpiration with nighttime HR. During HR, water efflux flushed solutes away from the root, diluting the concentrations of key nutrients like nitrate. The transport of cations by transpiration in the day and their accumulation near the root led to competitive desorption of ammonium from soil further from the root and generation of hotspots of ammonium availability at night. HR influenced the spatial and temporal patterns of these hotspots and their intensity. They were also influenced by soil properties of texture and cation exchange capacity. This dynamic resource landscape caused by diel cycling between transpiration and hydraulic redistribution presents a stage for greater complexity of microbial interactions. We are currently embedding a microbial community and small food web into this rhizosphere model in order to explore how organisms responsible for nutrient and soil carbon cycling respond to these fluctuating resource regimes.

  1. [Nutrient Characteristics and Nitrogen Forms of Rhizosphere Soils Under Four Typical Plants in the Littoral Zone of TGR].

    Science.gov (United States)

    Wang, Xiao-feng; Yuan, Xing-zhong; Liu, Hong; Zhang, Lei; Yu, Jian-jun; Yue, Jun-sheng

    2015-10-01

    The Three Gorges Reservoir (TGR), which is the largest water conservancy project ever built in tne world, produced a drawdown area of about 348.93 km2 because of water level control. The biological geochemical cycle of the soil in the drawdown zone has been changed as the result of long-term winter flooding and summer drought and vegetation covering. The loss of soil nitrogen in the drawdown zone poses a threat to the water environmental in TGR. Pengxi river, is an important anabranch, which has the largest drawdown area has been selected in the present study. The four typical vegetation, contained Cynodon dactylon, Cyperus rotundus, Anthium sibiricum and Zea mays L. as the control, were studied to measure nutrient characteristics and nitrogen forms of rhizosphere and non-rhizosphere soils in three distribution areas with different soil types (paddy soil, purple soil and fluvo-aquic soils). The variables measured included organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), hydrolysis N, available P and available K, pH, ion-exchangeable N (IEE-N), weak acid extractable N (CF-N) , iron-manganese oxides N (IMOF-N), organic matter sulfide N (OSF-N), added up four N forms for total transferable N (TF-N) and TN minus TF-N for non-transferable N (NTF-N). The results showed: (1) pH of rhizosphere soil was generally lower than that of non-rhizosphere soil under different vegetation in different type soils because the possible organic acid and H+ released form plant roots and cation absorption differences, and the OM, TP, TN and hydrolysis N of rhizosphere soil were generally higher than those of non-rhizosphere soil, and that the enrichment ratio (ER) of all the four nutrient indicators showed Cyperus rotundus > Cynodon dactylon > Zea mays L. > Anthium sibiricum. Available P showed enrichment in the rhizosphere of three natural vegetations but lose under corn, and available K, TK showed different ER in different conditions. (2) IEF-N CF

  2. Cyanobacterial inoculation elicits plant defense response and enhanced Zn mobilization in maize hybrids

    Directory of Open Access Journals (Sweden)

    Radha Prasanna

    2015-12-01

    Full Text Available The present investigation evaluated the effect of inoculating different cyanobacterial formulations on a set of hybrids of maize, in terms of plant defense enzyme activity, soil health parameters, Zn concentration, and yields. Microbial inoculation showed significant effects on accumulation of Zn in flag leaf, with A4 (Anabaena–Azotobacter biofilm recording the highest values. Analysis of variance (ANOVA indicated that both the hybrids and cyanobacterial treatments brought about significant variation in terms of glomalin-related soil proteins and polysaccharides in soil and the activity of defense enzymes in roots and shoots of the plants. Cyanobacterial inoculants—A4 (Anabaena–Azotobacter biofilm and A1 (Anabaena sp.–Providencia sp., CW1 + PW5 enhanced the activity of peroxidase, PAL and PPO in roots, which also showed a positive correlation with Zn concentration in the flag leaf. Grain yield ranged from 7.0 to 7.29 t/ha among the different inoculants. Comparative analyses of treatments showed that A3 (Anabaena–Trichoderma-biofilmed formulation and hybrid B8 (Bio-9681 were superior in terms of parameters investigated. This represents the first report on the genotypic responses of maize hybrids to cyanobacteria-based inoculants. Future research should focus on dissecting the role of root exudates and cyanobacteria-mediated Zn mobilization pathway in maize.

  3. Diversity and importance of filamentous bacteria in biological nutrient removal wastewater treatment plants – a worldwide survey

    DEFF Research Database (Denmark)

    Nierychlo, Marta; Ziegler, Anja Sloth; McIlroy, Simon Jon;

    bacteria in full-scale nutrient removal WWTPs. 16S rRNA gene amplicon sequencing was applied to survey 24 Danish and 30 worldwide full-scale biological nutrient removal WWTPs (total of >550 samples), where all known bacterial genera possessing filamentous morphology were investigated. Candidatus Microthrix...

  4. Phosphorylation of Arabidopsis ubiquitin ligase ATL31 is critical for plant carbon/nitrogen nutrient balance response and controls the stability of 14-3-3 proteins.

    Science.gov (United States)

    Yasuda, Shigetaka; Sato, Takeo; Maekawa, Shugo; Aoyama, Shoki; Fukao, Yoichiro; Yamaguchi, Junji

    2014-05-30

    Ubiquitin ligase plays a fundamental role in regulating multiple cellular events in eukaryotes by fine-tuning the stability and activity of specific target proteins. We have previously shown that ubiquitin ligase ATL31 regulates plant growth in response to nutrient balance between carbon and nitrogen (C/N) in Arabidopsis. Subsequent study demonstrated that ATL31 targets 14-3-3 proteins for ubiquitination and modulates the protein abundance in response to C/N-nutrient status. However, the underlying mechanism for the targeting of ATL31 to 14-3-3 proteins remains unclear. Here, we show that ATL31 interacts with 14-3-3 proteins in a phosphorylation-dependent manner. We identified Thr(209), Ser(247), Ser(270), and Ser(303) as putative 14-3-3 binding sites on ATL31 by motif analysis. Mutation of these Ser/Thr residues to Ala in ATL31 inhibited the interaction with 14-3-3 proteins, as demonstrated by yeast two-hybrid and co-immunoprecipitation analyses. Additionally, we identified in vivo phosphorylation of Thr(209) and Ser(247) on ATL31 by MS analysis. A peptide competition assay showed that the application of synthetic phospho-Thr(209) peptide, but not the corresponding unphosphorylated peptide, suppresses the interaction between ATL31 and 14-3-3 proteins. Moreover, Arabidopsis plants overexpressing mutated ATL31, which could not bind to 14-3-3 proteins, showed accumulation of 14-3-3 proteins and growth arrest in disrupted C/N-nutrient conditions similar to wild-type plants, although overexpression of intact ATL31 resulted in repression of 14-3-3 accumulation and tolerance to the conditions. Together, these results demonstrate that the physiological role of phosphorylation at 14-3-3 binding sites on ATL31 is to modulate the binding ability and stability of 14-3-3 proteins to control plant C/N-nutrient response.

  5. Electrical conductivity of the nutrient solution and plant density in aeroponic production of seed potato under tropical conditions (winter/spring)

    OpenAIRE

    Calori,Alex Humberto; Factor,Thiago Leandro; Feltran, José Carlos [UNESP; Watanabe,Eduardo Yuji; Moraes,Carolina Cinto de; Purquerio,Luís Felipe Villani

    2017-01-01

    ABSTRACT The recent introduction in Brazil of production of quality seed potatoes in hydroponic systems, such as aeroponics, demands studies on the nutritional and crop management. Thus, this study evaluated the influence of electrical conductivity of the nutrient solution and plant density on the seed potato minitubers production in aeroponics system. The Agata and Asterix cultivars were produced in a greenhouse under tropical conditions (winter/spring). The experimental design was a randomi...

  6. Produção de fitomassa e acúmulo de nutrientes na parte aérea do sorgo de Guiné gigante Biomass production and accumulation of nutrients in shoots of Giant Guinea sorghum plants

    Directory of Open Access Journals (Sweden)

    Gustavo Pavan Mateus

    2011-12-01

    Full Text Available A escolha de espécies com elevada produção de fitomassa para utilização como plantas de cobertura no sistema de semeadura direta é extremamente importante em regiões de inverno seco. O objetivo deste trabalho foi avaliar a produção de fitomassa e acúmulo de nutrientes na parte aérea das plantas de sorgo Guiné gigante (Sorghum bicolor subespécie bicolor raça guinea, semeados em diferentes épocas de semeadura. Foi utilizado um delineamento em blocos ao acaso, com seis tratamentos e quatro repetições. Os tratamentos foram constituídos por seis épocas de semeadura (25/09/2000; 25/10/2000; 24/11/2000; 22/12/2000; 22/02/2001 e 03/04/2001. Por ocasião do florescimento das plantas, avaliou-se a produção de matéria seca, o número e diâmetro de colmos e a altura das plantas. Também foi determinado o teor e acúmulo de macro e micronutrientes, além da relação C/N. O ciclo das plantas diminuiu com o atraso da época de semeadura, e, conseqüentemente, a produção de matéria seca e a relação C/N também foram menores. Comportamento contrário foi observado para o teor de nutrientes. O sorgo de Guiné gigante é sensível ao fotoperíodo e, portanto, semeaduras mais tardias ocasionam diminuição do crescimento das plantas, produção de biomassa e acúmulo de nutrientes. Esta espécie consiste em uma boa opção para cultivo como planta de cobertura no sistema de semeadura direta devido a alta produção de fitomassa e ciclagem de N, P e K.Choosing species with high phytomass production to be cropped in no tillage system is extremely important in dry winter regions. The purpose of this research was to study plant biomass production and accumulation of nutrients in shoots of Giant Guinea sorghum plants (Sorghum bicolor subspecies bicolor race Guinea sown in different sowing dates. A randomized complete block design with six treatments and four replications was performed. Treatments consisted of six sowing dates (09/25/2000; 10

  7. The interaction of heavy metals and nutrients present in soil and native plants with arbuscular mycorrhizae on the riverside in the Matanza-Riachuelo River Basin (Argentina).

    Science.gov (United States)

    Mendoza, Rodolfo E; García, Ileana V; de Cabo, Laura; Weigandt, Cristian F; Fabrizio de Iorio, Alicia

    2015-02-01

    This study assessed the contamination by heavy metals (Cr, Cu, Pb, Zn), and nutrients (N, P) in soils and native plants, and the effect of the concentration of those elements with the density of arbuscular-mycorrhizal (AM) spores in soil and colonization in roots from the riverside of the Matanza-Riachuelo River Basin (MRRB). The concentration of metals and nutrients in soils and plants (Eleocharis montana, Cyperus eragrostis, Hydrocotyle bonariensis) increased from the upper sites (8 km from headwaters) to the lower sites (6 km from the mouth of the Riachuelo River) of the basin. AM-colonization on the roots of H. bonariensis and spore density in soil decreased as the concentrations of metals in soil and plant tissues increased from the upper to lower sites of the basin within a consistent gradient of contamination associated with land use, soil disturbance, population, and chemicals discharged into the streams and rivers along the MRRB. The general trends for all metals in plant tissue were to have highest concentrations in roots, then in rhizomes and lowest in aerial biomass. The translocation (TF) and bioconcentration (BCF) factors decreased in plants which grow from the upper sites to the lower sites of the basin. The plants tolerated a wide range in type and quantity of contamination along the basin by concentrating more metals and nutrients in roots than in aboveground tissue. The AM spore density in soil and colonization in roots of H. bonariensis decreased with the increase of the degree of contamination (Dc) in soil. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Distribution and the Correlativety of Plant Nutrient Element in Carex lasiocarpa Wetland%毛果苔草湿地植物营养元素分布及其相关性

    Institute of Scientific and Technical Information of China (English)

    何池全

    2002-01-01

    The distribution of nutrient was different for different dominant plant species in C.lasiocarpa wetland ecosystem.The distribution of nutrient was also different for different plant components in Carex lasiocarpa.The gross nutrient element distribution for N,P,K,Ca,Mg,Cu and Fe in C.lasiocarpa was in order of:redicula>rhizoma>spike>blade>sheath>inflorescence.But this rule for the gross nutrient element distribution of Zn and Mn was not obvious.The seasonal dynamic trends of nutrient element contents in dead stand were decreaseing.The liberation of general elements N,P,K and microelement Mn were continuous,and with monotone downtrend;the liberation rate of microelement Cu,Zn,Fe were faster than other elemnts,while the trend for Ca was all through incremental.There were different degrees of correlativity among different nutrient elements in C. Lasiocarpa.

  9. Concentrations of some macro and micro plant nutrient of cultivated soils in Central and Eastern Blacksea Region and their mapping by inverse distance weighted (IDW method

    Directory of Open Access Journals (Sweden)

    Mehmet Arif Özyazıcı

    2015-11-01

    Full Text Available The aim of this study was to determine plant nutrients content and to in terms of soil variables their soil database and generate maps of their distribution on agricultural land in Central and Eastern Black Sea Region using geographical information system (GIS. In this research, total 3400 soil samples (0-20 cm depth were taken at 2.5 x 2.5 km grid points representing agricultural soils. Total nitrogen, extractable calcium, magnesium, sodium, boron, iron, copper, zinc and manganese contents were analysed in collected soil samples. Analysis results of these samples were classified and evaluated for deficiency, sufficiency or excess with respect to plant nutrients. Afterwards, in terms of GIS, a soil database and maps for current status of the study area were created by using inverse distance weighted (IDW interpolation method. According to this research results, it was determined sufficient plant nutrient elements in terms of total nitrogen, extractable iron, copper and manganese in arable soils of Central and Eastern Blacksea Region while, extractable calcium, magnesium, sodium were found good and moderate level in 66.88%, 81.44% and 64.56% of total soil samples, respectively. In addition, insufficient boron and zinc concentration were found in 34.35% and 51.36% of soil samples, respectively.

  10. The effect of nutrients shortage on plant's efficiency to capture solar radiations under semi-arid environments.

    Science.gov (United States)

    Hammad, Hafiz Mohkum; Abbas, Farhat; Ahmad, Ashfaq; Fahad, Shah; Laghari, Khalifa Qasim; Alharby, Hesham; Farhad, Wajid

    2016-10-01

    Radiation use efficiency (RUE) is considered critical for calculation of crop yield. The crop productivity can be improved by increasing the interception of solar radiation and maintaining higher RUE for plants. Irrigation water and nitrogen (N) supply are the main limiting factors for RUE in maize (Zea mays L.) across the semi-arid environments. Field experiments were conducted during two consecutive growing seasons (2009-2010) to optimize RUE in relation to N application timings and rates with varying irrigation water management practices. In experiment 1, three N application timings were made, while in experiment 2, three possible water management practices were used. In both experiments, five N rates (100, 150, 200, 250, and 300 kg N ha(-1)) were applied to evaluate the effects of irrigation water and N on cumulative photosynthetic active radiation (PARi), dry matter RUE (RUEDM), and grain yield RUE (RUEGY). The results demonstrated that cumulative PARi and RUEs were not constant during the plant growth under varying the nutrients. The water and N significantly influenced cumulative PARi and RUEs during the both growing seasons. In experiment 1, the maximum cumulative PARi was observed by application of 250 kg N ha(-1) in three splits (1/3 N at V2, 1/3 N at V16, and 1/3 N at R1 stage), and the highest RUEDM was achieved by the application of 300 kg N ha(-1). However, the highest RUEGY was observed by application of 250 kg N ha(-1). In experiment 2, the maximum cumulative PARi was attained at normal irrigation regime with 250 kg N ha(-1), while the highest RUEDM and RUEGY were recorded at normal irrigation regime with the application of 300 kg N ha(-1). The regression analysis showed significant and positive correlation of RUEGY with grain yield. Therefore, optimum water and N doses are important for attaining higher RUE, which may enhance maize grain yield semi-arid environment; this may be considered in formulating good agricultural practices

  11. Soil chemical characteristics, biomass production and levels of nutrient and heavy metals in corn plants according to doses of steel slag and limestone

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Santos Caetano

    Full Text Available ABSTRACT Steel slag presents potential for neutralizing the soil acidity instead of limestone and for supplying nutrients for plants. The objective of this work was to study the effect of steel slag on soil chemical characteristics, biomass production, and contents of nutrients and of heavy metals on dry matter of corn plants. The levels of P, K, Na, Ca, Mg, Cu, Fe, Zn, Mn, Si, Cd, Cr, Pb, and Ni were determined in steel slag and limestone (for comparison purposes and the growth of corn plants under increasing doses of slag and limestone (0 to 10 t ha-1 was evaluated. Steel slag presented higher levels of P, Fe, Zn, Mn, and Si when compared with limestone. No difference was found in the content of heavy metals of slag and limestone, except for Cr, which was higher in the slag. Limestone provided the greatest increase of soil pH over time. Slag increased the content of P, Si, and soil micronutrient, while limestone was more efficient in increasing the content of Mg. The levels of heavy metals in the soil increased with the application of slag, but they remained below critical level within agricultural parameters. Slag and limestone presented a similar effect on the increase of the initial production of corn biomass. The levels of heavy metals in dry matter of corn plants under increasing doses of slag and limestone were below the critical levels of the toxicity of these elements on most plants.

  12. Available nutrients in biochar

    Science.gov (United States)

    Biochar technology may contribute to the recovery and recycling of plant nutrients and thus add a fertilizer value to the biochar. Total nutrient content in biochars varies greatly and is mainly dependent on feedstock elemental composition and to a lesser extent on pyrolysis conditions. Availability...

  13. Responses of fungal root colonization, plant cover and leaf nutrients to long-term exposure to elevated atmospheric CO2 and warming in a subarctic birch forest understory

    DEFF Research Database (Denmark)

    Olsrud, Maria; Carlsson, Bengt Å.; Svensson, Brita M.

    2010-01-01

    Responses of the mycorrhizal fungal community in terrestrial ecosystems to global change factors are not well understood. However, virtually all land plants form symbiotic associations with mycorrhizal fungi, with approximately 20% of the plants' net primary production transported down....... To place the belowground results into an ecosystem context we also investigated how plant cover and nutrient concentrations in leaves responded to elevated atmospheric CO2 concentrations and warming. The ErM colonization in ericaceous dwarf shrubs increased under elevated atmospheric CO2 concentrations......, but did not respond to warming following 6 years of treatment. This suggests that the higher ErM colonization under elevated CO2 might be due to increased transport of carbon belowground to acquire limiting resources such as N, which was diluted in leaves of ericaceous plants under enhanced CO2...

  14. Nutrient Control Seminars

    Science.gov (United States)

    These Nutrient Control Seminars will present an extensive state-of-the-technology review of the engineering design and operation of nitrogen and phosphorous control technologies and techniques applied at municipal wastewater treatment plants (WWTPs). These seminars will present ...

  15. [New nutrient medium for the cultivation and isolation of the plague microbe ChDS-37 as an element of the mobilization reserve of specialized antiepidemic teams of the Russian Inspectorate for the Protection of Consumer Rights and Human Welfare].

    Science.gov (United States)

    Mazrukho, A B; Kaminskiĭ, D I; Lomov, Yu M; Telesmanich, N P; Rozhkov, K K; Alutin, I M; Pukhov, Yu M; Prometnoĭ, V I; Fetsaĭlova, O P; Bulakhova, O G; Firsova, I A; Smolikova, L M; Bozhko, N V; Ivanova, V S; Burlakova, O S; Verkina, L M; Trukhachev, A L; Akulova, M V

    2011-04-01

    A new nutrient medium has been designed to culture and isolate the plague microbe ChDS-37 on the basis of the pancreatic digest of baker's yeast. The results of laboratory tests of the designed medium, by using 10 plague microbe strains and those of approval during the tactical and special training of a specialized antiepidemic team (SAET), suggest that the medium has some advantage over reference media and creates prerequisites for being incorporated into the mobilization reserve of a SAET.

  16. ISRU Reactant, Fuel Cell Based Power Plant for Robotic and Human Mobile Exploration Applications

    Science.gov (United States)

    Baird, Russell S.; Sanders, Gerald; Simon, Thomas; McCurdy, Kerri

    2003-01-01

    Three basic power generation system concepts are generally considered for lander, rover, and Extra-Vehicular Activity (EVA) assistant applications for robotic and human Moon and Mars exploration missions. The most common power system considered is the solar array and battery system. While relatively simple and successful, solar array/battery systems have some serious limitations for mobile applications. For typical rover applications, these limitations include relatively low total energy storage capabilities, daylight only operating times (6 to 8 hours on Mars), relatively short operating lives depending on the operating environment, and rover/lander size and surface use constraints. Radioisotope power systems are being reconsidered for long-range science missions. Unfortunately, the high cost, political controversy, and launch difficulties that are associated with nuclear-based power systems suggests that the use of radioisotope powered landers, rovers, and EVA assistants will be limited. The third power system concept now being considered are fuel cell based systems. Fuel cell power systems overcome many of the performance and surface exploration limitations of solar array/battery power systems and the prohibitive cost and other difficulties associated with nuclear power systems for mobile applications. In an effort to better understand the capabilities and limitations of fuel cell power systems for Moon and Mars exploration applications. NASA is investigating the use of In-Situ Resource Utilization (ISRU) produced reactant, fuel cell based power plants to power robotic outpost rovers, science equipment, and future human spacecraft, surface-excursion rovers, and EVA assistant rovers. This paper will briefly compare the capabilities and limitations of fuel cell power systems relative to solar array/battery and nuclear systems, discuss the unique and enhanced missions that fuel cell power systems enable, and discuss the common technology and system attributes

  17. Exploitation of nutrient- and C-rich paleosols by deep rooting plants in Dutch drift- and coversands

    Science.gov (United States)

    Gocke, Martina; Kessler, Fabian; van Mourik, Jan; Jansen, Boris; Wiesenberg, Guido L. B.

    2015-04-01

    Plant roots are commonly assumed to be most abundant in topsoil, with strongly decreasing frequencies in underlying soil horizons with incrasing depth and almost absence of roots below the uppermost few dm due to unfavorable environmental conditions in terms of e.g. aeration, nutrient availability or water, that hamper root growth. It still remains unknown, to which extent roots might be able to exploit deeper parts of soils and underlying soil parent material as well as burried paleosols. The study site is located in SE Netherlands. Undisturbed oak forests developed about 200 years ago on stabilized driftsand, deposited on a plaggic Anthrosol after approximately 700 years of agricultural use. The soil profile, consisting of the recent initial Podzol in driftsand, overlying 1.1 m thick plaggic deposits that were established in a 0.5 m thick residual Podzol in coversand, was excavated in a pit of 2.3 m depth. Living and dead roots were counted throughout the profile on both, the vertical wall and horizontal levels. Additionally, soil or sediment samples free of visible root remains were collected in depth intervals between 0.05 m and 0.15 m from topsoil down to the coversand. A multi-proxy approach, including assessment of bulk elemental composition of soil, sediments and paleosol and molecular structure of organic matter therein, organic carbon contents, bulk density and pH was applied in order to comprehensively describe the varying environmental conditions within the soil profile and in transects from roots to root-free material. The burried agricultural soil revealed low density and high organic carbon contents compared to the coversand parent material, and especially in its lower part, high phosphorous contents. In contrast, the burried Podzol was characterized by completely different geochemical and physical properties, like increasing pH with depth and high iron and aluminium contents. In the recent initial Podzol, fine roots (≤ 2 mm), deriving from both

  18. Influence of phosphorus application and arbuscular mycorrhizal inoculation on growth, foliar nitrogen mobilization, and phosphorus partitioning in cowpea plants.

    Science.gov (United States)

    Taffouo, Victor Désiré; Ngwene, Benard; Akoa, Amougou; Franken, Philipp

    2014-07-01

    The present study was undertaken to evaluate the effects of phosphorus (P) application and arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae) on growth, foliar nitrogen mobilization, and phosphorus partitioning in cowpea (Vigna unguiculata cv. Vita-5) plants. The experiment was conducted in a greenhouse in pots containing a mixture of vermiculite and sterilized quartz sand. Mycorrhizal and non-mycorrhizal cowpea plants were supplied with three levels of soluble P (0.1 (low P), 0.5 (medium P), or 1.0 mM (high P)).Cowpea plants supplied with low P fertilization showed significantly (p fertilization at both the vegetative and pod-filling stages. P uptake and growth parameters of cowpea plants were positively influenced by mycorrhizal inoculation only in the medium P fertilization treatment at the vegetative stage. Lack of these effects in the other treatments may be linked to either a very low P supply (in the low P treatment at the vegetative stage) or the availability of optimal levels of freely diffusible P in the substrate towards the pod-filling stage due to accumulation with time. The N concentration in leaves of all cowpea plants were lower at the pod-filling stage than at the vegetative stage, presumably as a result of N mobilization from vegetative organs to the developing pods. This was however not influenced by AM fungal inoculation and may be a consequence of the lack of an improved plant P acquisition by the fungus at the pod-filling stage.

  19. Metagenomic profiling of antibiotic resistance genes and mobile genetic elements in a tannery wastewater treatment plant.

    Directory of Open Access Journals (Sweden)

    Zhu Wang

    Full Text Available Antibiotics are often used to prevent sickness and improve production in animal agriculture, and the residues in animal bodies may enter tannery wastewater during leather production. This study aimed to use Illumina high-throughput sequencing to investigate the occurrence, diversity and abundance of antibiotic resistance genes (ARGs and mobile genetic elements (MGEs in aerobic and anaerobic sludge of a full-scale tannery wastewater treatment plant (WWTP. Metagenomic analysis showed that Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria dominated in the WWTP, but the relative abundance of archaea in anaerobic sludge was higher than in aerobic sludge. Sequencing reads from aerobic and anaerobic sludge revealed differences in the abundance of functional genes between both microbial communities. Genes coding for antibiotic resistance were identified in both communities. BLAST analysis against Antibiotic Resistance Genes Database (ARDB further revealed that aerobic and anaerobic sludge contained various ARGs with high abundance, among which sulfonamide resistance gene sul1 had the highest abundance, occupying over 20% of the total ARGs reads. Tetracycline resistance genes (tet were highly rich in the anaerobic sludge, among which tet33 had the highest abundance, but was absent in aerobic sludge. Over 70 types of insertion sequences were detected in each sludge sample, and class 1 integrase genes were prevalent in the WWTP. The results highlighted prevalence of ARGs and MGEs in tannery WWTPs, which may deserve more public health concerns.

  20. Environmental feasibility study for deployment and construction of mobile gas turbine power plants in urbanized areas

    Directory of Open Access Journals (Sweden)

    Bryukhan Fedor

    2017-01-01

    Full Text Available In the view of current electrical shortage in some regions of Russia, mobile gas turbine power plants (MGTPP have become urgent in recent years. Usually they are used as back-up power sources to cover peak loads in power networks and to ensure uninterrupted power supply to consumers. This paper deals with environmental feasibility study for deployment and construction of the MGTPP in an urban setting. Technogehic factors of the MGTPP impact on the environment have been assessed and possibility of the MGTPP deployment at various sites in different regions of Russia has been identified. The necessity of using the technology of water injection into the gas turbine units combustion chamber to suppress nitrogen oxides in some cases is mentioned. Quantitative assessments of the MGTPP technogehic impact on the environment components have been performed using standard techniques. The calculations have revealed that the MGTPP specifications ensure the levels of technogehic impacts within the standard limits. The results have ensured preparation of pre-design and design documentation related to protection of the environment against the MGTPP complex technogehic impact.

  1. Evaluation of elemental profiling methods, including laser-induced breakdown spectroscopy (LIBS), for the differentiation of Cannabis plant material grown in different nutrient solutions.

    Science.gov (United States)

    El-Deftar, Moteaa M; Robertson, James; Foster, Simon; Lennard, Chris

    2015-06-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging atomic emission based solid sampling technique that has many potential forensic applications. In this study, the analytical performance of LIBS, as well as that of inductively coupled plasma mass spectrometry (ICP-MS), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and X-ray microfluorescence (μXRF), was evaluated for the ability to conduct elemental analyses on Cannabis plant material, with a specific investigation of the possible links between hydroponic nutrients and elemental profiles from associated plant material. No such study has been previously published in the literature. Good correlation among the four techniques was observed when the concentrations or peak areas of the elements of interest were monitored. For Cannabis samples collected at the same growth time, the elemental profiles could be related to the use of particular commercial nutrients. In addition, the study demonstrated that ICP-MS, LA-ICP-MS and LIBS are suitable techniques for the comparison of Cannabis samples from different sources, with high discriminating powers being achieved. On the other hand, μXRF method was not suitable for the discrimination of Cannabis samples originating from different growth nutrients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Nutrição mineral e extração de nutrientes de planta de milho irrigada com água salina Mineral nutrition and extraction of nutrients by corn plant irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Geocleber G. de Sousa

    2010-11-01

    Full Text Available A utilização de água salina na agricultura irrigada pode causar desequilíbrio nutricional e inibição competitiva na absorção de nutrientes. O objetivo deste trabalho foi avaliar os efeitos da salinidade da água de irrigação sobre o acúmulo, os totais extraídos e a distribuição de nutrientes em plantas de milho. O estudo foi conduzido em condições de campo em um Argissolo Vermelho Amarelo na estação seca, no delineamento em blocos ao acaso, com cinco repetições, de setembro a dezembro de 2007, em Fortaleza, CE. As plantas de milho foram coletadas aos 90 dias após a semeadura e realizadas as seguintes avaliações: teores, extração e distribuição de elementos minerais nas diferentes partes da planta (folha, colmo, grão e sabugo. O aumento da salinidade da água de irrigação aos 90 dias após a semeadura, inibiu o acúmulo de potássio nas folhas e de magnésio e fósforo nos grãos. A extração dos nutrientes e sódio pelas plantas irrigadas com água de salinidade variando de 0,8 a 3,6 dS m-1 obedeceu à seguinte ordem decrescente: K > Mg > Ca > P > Na; no tratamento de maior salinidade (5,0 dS m-1 a sequência de extração foi: K > Ca > Na > P > Mg.The use of saline water in irrigated agriculture can cause nutritional imbalance and competitive inhibition in the absorption of nutrients. The objective of this study was to evaluate the effects of salinity of irrigation water on the accumulation, the total absorption, and the distribution of mineral elements in maize plants. The study was conducted under field conditions in an Yellow Red Argisol in the dry season, in the randomized blocks design with five replicates during September to December 2007 in Fortaleza - CE. The maize plants were collected at 90 days after sowing, and the following assessments were made: content, extraction and distribution of mineral elements in the plant parts (leaf, stem, grain and elderberry. The increase of salinity of irrigation water

  3. Controls on phosphorous mobility in the Potomac River near the Blue Plains wastewater treatment plant

    Science.gov (United States)

    Hearn,, Paul P.

    1985-01-01

    The Blue Plains wastewater treatment plant is the largest point source of phosphorus in the Potomac River basin, discharging an average of 2 metric tons of phosphorus into the river each day in 1980. An intensive study of the water and sediments in the vicinity of the treatment plant was conducted in 1979-80 in order to characterize the major factors controlling the mobility of effluent-derived phosphorus in the area. The transport of phosphorus near the treatment plant was found to be affected by the circulation regime, by inorganic adsorption reactions with sediments, and by metabolic uptake and release by phytoplankton. The effect of river discharge on the convective transport of phosphorus near the outfall is significantly reduced by a mid-river shoal area, which confines the flow path of the effluent to an embayment on the eastern side of the river for a distance of 4 kilometers below the outfall. This embayment appears to serve as a sediment trap, where protection from bottom scour during high-flow events has permitted fine-grained sediments to accumulate. Measurements of mean residence time indicate that the effluent leaves the embayment area 21? days after being discharged from the outfall. Measurements of the linear decay constant for the removal of dissolved phosphorus from the water column reveal a diurnal cycle corresponding to the metabolic utilization of phosphorus by phytoplankton. This cyclic removal is superimposed on a constant and noncyclic adsorption of phosphorus by inorganic phases. Forty-eight hour average values of the linear decay constant for dissolved phosphorus in the area range from 0.4 to 1.1 per day. Analyses of bottom sediments indicate that approximately 13 percent of the phosphorus discharged between September 1977 and August 1980 has been retained in the embayment. The primary inorganic phase responsible for phosphorus adsorption is amorphous iron (ferric oxy-hydroxides); amorphous aluminum and clay minerals appear to play

  4. EFECTOS BENEFICOS DE BACTERIAS RIZOSFÉRICAS EN LA DISPONIBILIDAD DE NUTRIENTES EN EL SUELO Y LA ABSORCIÓN DE NUTRIENTES POR LAS PLANTAS A REVIEW ON BENEFICIAL EFFECTS OF RHIZOSPHERE BACTERIA ON SOIL NUTRIENT AVAILABILITY AND PLANT NUTRIENT UPTAKE

    Directory of Open Access Journals (Sweden)

    Nelson Walter Osorio Vega

    2007-06-01

    participan en el biocontrol de patógenos de plantas. Debido a estos beneficios sobre la nutrición y el crecimiento vegetal estas bacterias rizosfericas han sido llamadas “rizobacterias promotoras del crecimiento vegetal” (PGPR, por sus siglas en inglés.This paper is a review of the benefits of rhizosphere bacteria on plant nutrition. The interaction between plant and phosphate-solubilizing- bacteria is explained in more detail and used as model to illustrate the role that rhizosphere bacteria play on soil nutrient availability. Environmental conditions of rhizosphere and mycorrhizosphere are also discussed. Plants can release carbohydrates, aminoacids, lipids, and vitamins trough their roots to stimulate microorganisms in the soil. The soil volume affected by these root exudates, aproximately 2 mm from the root surface, is termed rhizosphere. Rhizosphere bacteria participate in the geochemical cycling of nutrients and determine their availability for plants and soil microbial community. For instance, in the rhizosphere there are organisms able to fix N2 forming specialized structures (e.g., Rhizobium and related genera or simply establishing associative relationships (e.g. Azospirillium, Acetobacter. On the other hand, bacterial ammonifiers and nitrifiers are responsible for the conversion of organic N compounds into inorganic forms (NH4+ and NO3- which are available for plants. Rhizosphere bacteria can also enhance the solubility of insoluble minerals that control the availability of phosphorus (native or applied using for that organic acids or producing phosphatases that act on organic phosphorus pools. The availability of sulfur, iron and manganese are also affected by redox reactions carried out by rhizosphere bacteria. Likewise, chelating agents can control the availability of micronutrients and participate in mechanisms of biocontrol of plant pathogens. Due to these and other benefits on plant growth, some rhizosphere bacteria have been called Plant Growth

  5. A new semi-mobile plant for radiation processing of waste

    Energy Technology Data Exchange (ETDEWEB)

    Tata, A. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione; Liccione, G. [ENEA, Centro Ricerche Trisaia, Policoro (Malta). Dipt. Ambiente; Jacoboni, V.; Fantini, M.; Schwarz, M. [Hitesys R-D-Corp., Aprilia, Latina (Italy)

    1998-04-01

    A new pilot/demonstrative semi-mobile irradiation plant, named TRIRIS (TRIsaia-RIfiuti-Sterilizzazione, namely `Trisaia Res. Center - Wastes- Sterilization`) has been designed and erected. The plant goal is recognized in proposing and exploring new technological opportunities, based on an `in-situ` effective processing of solid or liquid waste, mainly with reference to emergency situations (e.g. need of a quick environmental restoring operation following an accidental groundwater pollution). The project, which was jointly carried out by ENEA and Hitesys Co. and Italian electrons accelerators manufacturer, foresees a LINAC type EB-machine (s band) having 4-6 M e V and till 1000 W as beam features. Scattered radiation shielding is performed by a water pool surrounding the EB-machine head, filled up before operations. The plant, that is to be located at ENEA-Trisaia Res. Center (Basilicata southern of Italy), allows a large operative flexibility: groundwater and wastewater decontamination (1800 to 70 kg/h in the 1 to 25 kGy does range), organic and chlorinated waste streams (25 kg/h at 75 kGy), solid hospital wastes (50 kg/h at 35 kGy) or hazardous wastes like polycyclic aromatic compounds (180 to 35 kg/h in the 10 to 50 kGy dose range). [Italiano] Un nuovo impianto di irraggiamento semi-mobile pilota-dimostrativo, denominato TRIRIS (TRIsaia-RIfiuti-Sterilizzazione), e` stato progettato e realizzato con finalita` di proposizione e valutazione di nuove opportunita` tecnologiche di trattamenti `in-situ` di rifiuti solidi e liquidi, in particolare con riferimento a situazioni di emergenza (es. necessita` di un veloce recupero ambientale a seguito di un evento accidentale con effetti di inquinamento della falda acquifera). Il progetto, che e` stato condotto congiuntamente da ENEA e dalla Soc. Hitesys s.p.a., azienda italiana di fabbricazione di acceleratori di elettroni, prevede l`utilizzo di una macchina acceleratrice del tipo LINAC (in banda s) avente come energia e

  6. Interpretation of bioassays in the study of interactions between soil organisms and plants: involvement of nutrient factors

    NARCIS (Netherlands)

    Troelstra, S.R.; Wagenaar, R.; Smant, W.; Peters, B.A.M.

    2001-01-01

    Increased plant growth in sterilized soil is usually ascribed to the elimination of (often unidentified) soil-borne pathogens. Plant-soil bioassays are reported here for three dune soils and two plant species (Ammophila arenaria and Carer arenaria). Dynamics of plant growth, availability and uptake

  7. Effects of Mode of Target Task Selection on Learning about Plants in a Mobile Learning Environment: Effortful Manual Selection versus Effortless QR-Code Selection

    Science.gov (United States)

    Gao, Yuan; Liu, Tzu-Chien; Paas, Fred

    2016-01-01

    This study compared the effects of effortless selection of target plants using quick respond (QR) code technology to effortful manual search and selection of target plants on learning about plants in a mobile device supported learning environment. In addition, it was investigated whether the effectiveness of the 2 selection methods was…

  8. Isolation and Identification of Indigenous Plant Growth Promoting Rhizobacteria from Himalayan Region of Kashmir and their Effect on Improving Growth and Nutrient Contents of Maize (Zea Mays L.

    Directory of Open Access Journals (Sweden)

    Mahwish eZahid

    2015-03-01

    Full Text Available IIntroduction and exploitation of plant growth promoting rhizobacteria (PGPR in agro-ecosystems enhance plant-microbes interactions that may affect ecosystems sustainability, agricultural productivity and environmental quality. The present study was conducted to isolate and identify PGPRs associated with maize (Zea mays L. from twenty sites of Himalayan region of Hajira-Rawalakot, Azad Jammu and Kashmir (AJK, Pakistan. A total of one hundred isolates were isolated from these sites, out of which eight (HJR1, HJR2, HJR3, HJR4, HJR5, MR6, HJR7, HJR8 were selected in vitro for their plant growth promoting ability (PGPA including phosphorus solubilization, indole acetic acid (IAA production and N2 fixation. The 16S rRNA gene sequencing technique was used for molecular identity and authentication. Isolates were then further tested for their effects on growth and nutrient contents of maize (Zea mays L. under pouch and pot conditions. The 16S rRNA gene sequencing and phylogenetic analysis identified these isolates belong to Pseudomonas and Bacillus genera. The isolates promoted plant growth by solubilizing soil P which ranged between 19.2 and 35.6 µgmL−1. The isolates HJR1, HJR2, HJR3 and HJR5 showed positive activity in acetylene reduction assay showing their N2-fixation potential. All eight isolates showed the potential to produce IAA in the range of 0.9−5.39 µgmL−1 and promote plant growth. Results from a subsequent pot experiment indicated PGPRs distinctly increased maize shoot and root length, shoot and root dry weight, root surface area, leaf surface area, shoot and root N and P contents. Among the eight isolates, HR3 showed a marked P-solubilizing activity, plant growth-promoting attributes, and the potential to be developed as a biofertilizers for integrated nutrient management strategies

  9. Isolation and identification of indigenous plant growth promoting rhizobacteria from Himalayan region of Kashmir and their effect on improving growth and nutrient contents of maize (Zea mays L.).

    Science.gov (United States)

    Zahid, Mahwish; Abbasi, M Kaleem; Hameed, Sohail; Rahim, Nasir

    2015-01-01

    Introduction and exploitation of plant growth promoting rhizobacteria (PGPR) in agro-ecosystems enhance plant-microbes interactions that may affect ecosystems sustainability, agricultural productivity, and environmental quality. The present study was conducted to isolate and identify PGPRs associated with maize (Zea mays L.) from twenty sites of Himalayan region of Hajira-Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. A total of 100 isolates were isolated from these sites, out of which eight (HJR1, HJR2, HJR3, HJR4, HJR5, MR6, HJR7, HJR8) were selected in vitro for their plant growth promoting ability (PGPA) including phosphorus solubilization, indole-3-acetic acid (IAA) production and N2 fixation. The 16S rRNA gene sequencing technique was used for molecular identity and authentication. Isolates were then further tested for their effects on growth and nutrient contents of maize (Z. mays L.) under pouch and pot conditions. The 16S rRNA gene sequencing and phylogenetic analysis identified these isolates belong to Pseudomonas and Bacillus genera. The isolates promoted plant growth by solubilizing soil P which ranged between 19.2 and 35.6 μg mL(-1). The isolates HJR1, HJR2, HJR3, and HJR5 showed positive activity in acetylene reduction assay showing their N2-fixation potential. All eight isolates showed the potential to produce IAA in the range of 0.9-5.39 μg mL(-1) and promote plant growth. Results from a subsequent pot experiment indicated PGPRs distinctly increased maize shoot and root length, shoot and root dry weight, root surface area, leaf surface area, shoot and root N and P contents. Among the eight isolates, HR3 showed a marked P-solubilizing activity, plant growth-promoting attributes, and the potential to be developed as a biofertilizers for integrated nutrient management strategies.

  10. Productivity and accumulation of nutrients in plants of jambu, under mineral and organic fertilizationProdutividade e acúmulo de nutrientes em plantas de jambu, sob adubação orgânica e mineral

    Directory of Open Access Journals (Sweden)

    Luciana da Silva Borges

    2013-03-01

    Full Text Available The organic production is a system that allows achieving good levels of productivity, while avoiding the risks of chemical contamination of farmers, consumers and the environment. Because jambu plant is widely used as alternative medicine and cosmetics industries, has been increasing interest in its cultivation. The aim of this study was to analyze the biomass, accumulation of nutrient, productivity and determine the pesticide residue in plant jambu when grown under organic and mineral fertilization. The experiment was conducted at the Experimental Farm São Manuel, FCA / UNESP. The experiment was conducted at São Manuel Experimental Farm UNESP. The statistical was arranged in the randomized block design, in a 2 x 6 factorial scheme, two sources of fertilizers (organic and mineral and six doses of nitrogen, with four replications. The characteristics evaluated were plant height, fresh and dry weight, nutrients of accumulation in shoots and productivity. Mineral fertilizer gave higher biomass, productivity and accumulation of N and K in relation to organic fertilizer used. It is recommended the dose of 90g m-2 of urea as appropriate to obtain these results. However the organic fertilization favored the accumulation of phosphorus in plants jambu in relation the mineral fertilizer, and the dose of 10 kg m-2 of cattle manure recommended to achieve this result in plants jambu. We did not detect the presence of phosphorous and carbamate on leaves of jambu under organic and mineral fertilization. However, we observed the presence of chlorine in the leaves used for the two fertilizations.A produção orgânica é um sistema que permite alcançar bons níveis de produtividade, evitando ao mesmo tempo os riscos de contaminação química do agricultor, dos consumidores e do meio ambiente. Pelo fato da planta de jambu ser bastante utilizada como medicamento alternativo e por indústrias de cosméticos, vem aumentando o interesse pelo seu cultivo. Assim, o

  11. Spatial and Temporal Patterns of Nutrient Limitation, Plant Biomass and Productivity, and Stream Metabolism Vary in Response to Short- and Long-Term Hydrological Regime Shifts

    Science.gov (United States)

    Grimm, N. B.; Sabo, J. L.; Dong, X.; Ruhí, A.

    2014-12-01

    Climate and hydrology are strong drivers of ecosystem structure and function in arid landscapes. Arid regions are characterized by high interannual variation in precipitation, and these climate patterns drive the overall hydrologic disturbance regime (in terms of flooding and drying), which influences geomorphic structure, biotic distributions, and nutrient status of desert stream ecosystems. We analyzed the long-term pattern of discharge in a desert stream in Arizona to identify hydrologic regime shifts, i.e., abrupt transitions between sequences of floods and droughts at periods of months to decades. We used wavelet analysis to identify time intervals over a 50-year time series that were negatively correlated with one another, reflecting a shift from wet to dry phases. We also looked with finer resolution at the most recent 10-year period, when wetlands have come to dominate the ecosystem owing to a management change, and at individual flood and drought events within years. In space, there is high site fidelity of wetland plant cover, corresponding to reliable water sources. Comparing five-year patterns of plant distribution and stream metabolism between wet and dry years suggested the primacy of geomorphic controls in drought periods. Nutrient limitation of algal production varied from moderate to very strong N limitation, with only one year when there was a (weak) suggestion of secondary P limitation. Over the longer period of record, we identified times characterized by hydrological regime shifts and asked whether ecosystem variables would have changed over that time period. We hypothesized, in particular, that the changes in nutrient status of the stream ecosystem would result from these regime shifts. We used our most complete long-term dataset on stream nitrogen (N) and phosphorus (P) concentrations and N:P ratios as a proxy for nutrient limitation. However, N:P varied primarily at fine scales in response to individual flood events.

  12. Ecological role of reindeer summer browsing in the mountain birch (Betula pubescens ssp. czerepanovii) forests: effects on plant defense, litter decomposition, and soil nutrient cycling.

    Science.gov (United States)

    Stark, Sari; Julkunen-Tiitto, Riitta; Kumpula, Jouko

    2007-03-01

    Mammalian herbivores commonly alter the concentrations of secondary compounds in plants and, by this mechanism, have indirect effects on litter decomposition and soil carbon and nutrient cycling. In northernmost Fennoscandia, the subarctic mountain birch (Betula pubescens ssp. czerepanovii) forests are important pasture for the semidomestic reindeer (Rangifer tarandus). In the summer ranges, mountain birches are intensively browsed, whereas in the winter ranges, reindeer feed on ground lichens, and the mountain birches remain intact. We analyzed the effect of summer browsing on the concentrations of secondary substances, litter decomposition, and soil nutrient pools in areas that had been separated as summer or winter ranges for at least 20 years, and we predicted that summer browsing may reduce levels of secondary compounds in the mountain birch and, by this mechanism, have an indirect effect on the decomposition of mountain birch leaf litter and soil nutrient cycling. The effect of browsing on the concentration of secondary substances in the mountain birch leaves varied between different years and management districts, but in some cases, the concentration of condensed tannins was lower in the summer than in the winter ranges. In a reciprocal litter decomposition trial, both litter origin and emplacement significantly affected the litter decomposition rate. Decomposition rates were faster for the litter originating from and placed into the summer range. Soil inorganic nitrogen (N) concentrations were higher in the summer than in the winter ranges, which indicates that reindeer summer browsing may enhance the soil nutrient cycling. There was a tight inverse relationship between soil N and foliar tannin concentrations in the winter range but not in the summer range. This suggests that in these strongly nutrient-limited ecosystems, soil N availability regulates the patterns of resource allocation to condensed tannins in the absence but not in the presence of browsing.

  13. Densidade de plantio na produtividade e nos teores de nutrientes nas folhas e frutos da bananeira cv. Thap Maeo Plants density on yield and nutrients concentration in leaves and fruits of banana cv. Thap Maeo

    Directory of Open Access Journals (Sweden)

    Adônis Moreira

    2007-01-01

    Full Text Available O objetivo deste estudo foi avaliar o efeito da densidade de plantio na produtividade, tempo de colheita e teores dos nutrientes nas folhas e nos frutos de bananeira cv. Thap Maeo (AAB cultivada em Manaus (AM. O delineamento experimental foi o de blocos casualizados, com três repetições. Os tratamentos foram constituídos pelos fatores: três densidades de plantio (1.111; 1.667 e 3.333 plantas ha-1 e duas épocas de colheita (primeiro e segundo ciclos. Os resultados do primeiro e segundo ciclos mostraram incremento significativo da produtividade, com aumento da densidade de plantio. O tempo médio para colheita dos cachos foi menor na densidade de 1.111 plantas ha-1 (1º ciclo, 338 e 2º ciclo, 401 dias. Na média das densidades e independentemente do ciclo, os teores de macronutrientes nos frutos apresentaram a ordem de: K>N>P>Mg>Ca=S, enquanto a dos micronutrientes foi: 1º ciclo - Cl>Fe>Mn=B>Zn>Cu e 2º ciclo - Cl>Fe>Zn>B=Mn>Cu.This study aimed to evaluate the effect of plants density on yield, period of harvest and nutrients concentration in leaves and fruits of banana cv. Thap Maeo (AAB, cultivated in Manaus, State of Amazonas, Brazil. The experiment was conduced in a randomized blocks, with three replicates. Treatments were comprised of planting density (1,111; 1,667 and 3,333 plants ha-1, and two cycles of harvest (sub treatments. The results obtained from 1st cycle and 2nd cycle showed significant increase in the yield per unit area as the employed plant density increased. The shortest average period to harvest banana bunches (1st cycle, 338 days and 2nd cycle, 401 days was observed for the lower density (1,111 plants ha-1. Pooled data of density and cycles showed that exportation of macronutrients through the fruits was, in order: K>N>P>Mg>Ca=S, while in micronutrients was: 1st cycle - Cl>Fe>Mn=B>Zn>Cu, and 2nd cycle - Cl>Fe>Zn>B=Mn>Cu.

  14. Electrical conductivity of the nutrient solution and plant density in aeroponic production of seed potato under tropical conditions (winter/spring

    Directory of Open Access Journals (Sweden)

    Alex Humberto Calori

    Full Text Available ABSTRACT The recent introduction in Brazil of production of quality seed potatoes in hydroponic systems, such as aeroponics, demands studies on the nutritional and crop management. Thus, this study evaluated the influence of electrical conductivity of the nutrient solution and plant density on the seed potato minitubers production in aeroponics system. The Agata and Asterix cultivars were produced in a greenhouse under tropical conditions (winter/spring. The experimental design was a randomized block in a split-split plot design. The plot consisted of 4 electrical conductivities of the nutrient solution (1.0; 2.0; 3.0; and 4.0 dS∙m−1; the subplot, of 4 plant densities (25; 44; 66; and 100 plants∙m−2; and the subsubplot, of the 2 potato cultivars (Ágata and Asterix, totaling 4 blocks. The 2.2 and 2.1 dS∙m−1 electrical conductivities yielded the highest productivity of seed potato minitubers, for Ágata and Asterix cultivars, respectively, regardless of plant density. For both cultivars, the highest yield was observed for the 100 plants∙m−2 density.

  15. Wireless Power System Design for Mobile Robots used in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Choi, S. Y.; Yoo, S. J.; Lee, Kun J.; Rim, C. T. [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2012-05-15

    The robots used in nuclear power plants (NPP) have received much attention in recent years due to the Fukushima nuclear accident, which is considered as one of the worst nuclear disasters. In general, the NPP robots can play important roles in fuel exchange, repair work, radiation monitoring, rescue, and scouting out NPP. Under these conditions, human access to NPP during normal and emergency operations is strictly restricted due to the risks of high level radiation and contamination. However, in practice, robots have not been widely used in NPP because of the following limitations. First, the NPP robots cannot be of multi-purpose use because of their mission complexity and uniqueness. Second, the demand of the NPP robots is low due to the limited number of NPP over the world. Third, the NPP robots developed so far have no enough confidence in spite of the improvement of robot technology. Lastly, the NPP robots cannot carry on their mission continuously due to the limited energy capacity of the battery: mobile robots should stop working every two hours to recharge their batteries and spend least twenty minutes. As the solutions for this 'energy hungry' problem, high capacity batteries, quick battery chargers, power cables, and internal combustion engines were proposed; however, they still have the problems such as limited mission time and range, frequent recharging, or exhausting emission and noise. In this paper, the wireless power transfer systems (WPTS) for NPP robots are proposed. This technology can let NPP robots free from mission time and range limits, and exhausting emission. The requirements for the NPP robots are newly proposed, and two types of WPTS, roaming and railway, are suggested in this paper

  16. Inoculation with Metal-Mobilizing Plant-Growth-Promoting Rhizobacterium Bacillus sp. SC2b and Its Role in Rhizoremediation.

    Science.gov (United States)

    Ma, Ying; Oliveira, Rui S; Wu, Longhua; Luo, Yongming; Rajkumar, Mani; Rocha, Inês; Freitas, Helena

    2015-01-01

    A plant growth-promoting bacterial (PGPB) strain SC2b was isolated from the rhizosphere of Sedum plumbizincicola grown in lead (Pb)/zinc (Zn) mine soils and characterized as Bacillus sp. based on (1) morphological and biochemical characteristics and (2) partial 16S ribosomal DNA sequencing analysis. Strain SC2b exhibited high levels of resistance to cadmium (Cd) (300 mg/L), Zn (730 mg/L), and Pb (1400 mg/L). This strain also showed various plant growth-promoting (PGP) features such as utilization of 1-aminocyclopropane-1-carboxylate, solubilization of phosphate, and production of indole-3-acetic acid and siderophore. The strain mobilized high concentration of heavy metals from soils and exhibited different biosorption capacity toward the tested metal ions. Strain SC2b was further assessed for PGP activity by phytagar assay with a model plant Brassica napus. Inoculation of SC2b increased the biomass and vigor index of B. napus. Considering such potential, a pot experiment was conducted to assess the effects of inoculating the metal-resistant PGPB SC2b on growth and uptake of Cd, Zn and Pb by S. plumbizincicola in metal-contaminated agricultural soils. Inoculation with SC2b elevated the shoot and root biomass and leaf chlorophyll content of S. plumbizincicola. Similarly, plants inoculated with SC2b demonstrated markedly higher Cd and Zn accumulation in the root and shoot system, indicating that SC2b enhanced Cd and Zn uptake by S. plumbizincicola through metal mobilization or plant-microbial mediated changes in chemical or biological soil properties. Data demonstrated that the PGPB Bacillus sp. SC2b might serve as a future biofertilizer and an effective metal mobilizing bioinoculant for rhizoremediation of metal polluted soils.

  17. Costs of defense and a test of the carbon-nutrient balance and growth-differentiation balance hypotheses for two co-occurring classes of plant defense.

    Directory of Open Access Journals (Sweden)

    Tara Joy Massad

    Full Text Available One of the goals of chemical ecology is to assess costs of plant defenses. Intraspecific trade-offs between growth and defense are traditionally viewed in the context of the carbon-nutrient balance hypothesis (CNBH and the growth-differentiation balance hypothesis (GDBH. Broadly, these hypotheses suggest that growth is limited by deficiencies in carbon or nitrogen while rates of photosynthesis remain unchanged, and the subsequent reduced growth results in the more abundant resource being invested in increased defense (mass-balance based allocation. The GDBH further predicts trade-offs in growth and defense should only be observed when resources are abundant. Most support for these hypotheses comes from work with phenolics. We examined trade-offs related to production of two classes of defenses, saponins (triterpenoids and flavans (phenolics, in Pentaclethra macroloba (Fabaceae, an abundant tree in Costa Rican wet forests. We quantified physiological costs of plant defenses by measuring photosynthetic parameters (which are often assumed to be stable in addition to biomass. Pentaclethra macroloba were grown in full sunlight or shade under three levels of nitrogen alone or with conspecific neighbors that could potentially alter nutrient availability via competition or facilitation. Biomass and photosynthesis were not affected by nitrogen or competition for seedlings in full sunlight, but they responded positively to nitrogen in shade-grown plants. The trade-off predicted by the GDBH between growth and metabolite production was only present between flavans and biomass in sun-grown plants (abundant resource conditions. Support was also only partial for the CNBH as flavans declined with nitrogen but saponins increased. This suggests saponin production should be considered in terms of detailed biosynthetic pathway models while phenolic production fits mass-balance based allocation models (such as the CNBH. Contrary to expectations based on the two

  18. Effects of geotextile landscape fabric on soil nutrient availability in an organic planting of ‘Marion’ trailing blackberry

    Science.gov (United States)

    Geotextile landscape fabric, often referred to as weed mat, is becoming a popular option for weed control in many fruit crops, particularly for organic production. The present study was conducted in 2014 to evaluate the effects of landscape fabric relative to hand weeding on soil nutrient availabili...

  19. Sulphur and nitrogen supply - soil acidification and the absorption of nutrients in plants; Svovel og nitrogentilfoersel - jordforsuring og plantenes naeringstilgang

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamsen, G.

    1996-01-01

    Ecologically, soil is of the greatest interest as a growth medium for plants, and which affects the quality of ground water and surface water. In this connection, the paper looks upon how the increased deposition of sulphur, nitrogen and hydrogen ions affect the quality of soil as a growth medium for plants. Topics cover: Interaction between soil and plants, effects of acid rain in soil, and the effects of acid rain on plants. 11 refs., 1 tab.

  20. Yield performance and leaf nutrient levels of coffee cultivars under different plant densities Produtividade e níveis foliares de nutrientes em cultivares de café sob diferentes populações de plantas

    Directory of Open Access Journals (Sweden)

    Edison Martins Paulo

    2010-12-01

    Full Text Available Coffee (Coffea Arabica L. plantations using adapted cultivars to regional environmental conditions with optimal plant population density and adequate nutrition are expected to show high yield responses. The triennial production and leaf macronutrient concentrations of four coffee cultivars were studied under different plant population densities. Catuaí Amarelo (IAC 47, Obatã (IAC 1669-20, Acaiá (IAC 474-19 and Icatu Amarelo (IAC 2944 were planted in densities of 2,500; 5,000; 7,519; and 10,000 plants ha-1 with one plant per hole and two plants per hole in the 2,500 plant ha-1. Plants were homogeneously fertilized without liming. As the population density increased the triennial coffee productivity increased, the yield per plant decreased, and leaf concentrations of phosphorus (P, potassium (K and sulfur (S increased. Coffee plants under dense systems presented equal or higher leaf macronutrient concentrations compared to the plants under conventional population. Taller cultivars presented the highest nutrient concentration values, and Obatã, a dwarf cultivar, the lowest values. Higher coffee yields and lower leaf P, Ca and S concentrations were observed in plots with one plant compared to the plots with two plants. In general, the coffee cultivars had leaf N and S concentrations above the reference limits reported in the literature, but leaf concentrations of other macronutrients were within adequate ranges.Cultivares de cafeeiro (Coffea Arabica L. adaptadas às regiões de cultivo, com população de plantas otimizada e adequado estado nutricional são premissas para a obtenção de produções elevadas de café. Estudou-se a produção trienal de café e o teor foliar de macronutrientes de cultivares de cafeeiro em função das densidades de plantio. Foram utilizados os cultivares Catuaí Amarelo (IAC 47, Obatã (IAC 1669-20, Acaiá (IAC 474-19 e Icatu Amarelo (IAC 2944 nas populações de 2.500 plantas ha-1 com duas plantas por cova; e, 5

  1. Thresholds in the response of free-floating plant abundance to variation in hydraulic connectivity, nutrients, and macrophyte abundance in a large floodplain river

    Science.gov (United States)

    Giblin, Shawn M.; Houser, Jeffrey N.; Sullivan, John F.; Langrehr, H.A.; Rogala, James T.; Campbell, Benjamin D.

    2014-01-01

    Duckweed and other free-floating plants (FFP) can form dense surface mats that affect ecosystem condition and processes, and can impair public use of aquatic resources. FFP obtain their nutrients from the water column, and the formation of dense FFP mats can be a consequence and indicator of river eutrophication. We conducted two complementary surveys of diverse aquatic areas of the Upper Mississippi River as an in situ approach for estimating thresholds in the response of FFP abundance to nutrient concentration and physical conditions in a large, floodplain river. Local regression analysis was used to estimate thresholds in the relations between FFP abundance and phosphorus (P) concentration (0.167 mg l−1L), nitrogen (N) concentration (0.808 mg l−1), water velocity (0.095 m s−1), and aquatic macrophyte abundance (65 % cover). FFP tissue concentrations suggested P limitation was more likely in spring, N limitation was more likely in late summer, and N limitation was most likely in backwaters with minimal hydraulic connection to the channel. The thresholds estimated here, along with observed patterns in nutrient limitation, provide river scientists and managers with criteria to consider when attempting to modify FFP abundance in off-channel areas of large river systems.

  2. Physiological indexese macro- and micronutrients in plant tissue and essential oil of Mentha piperita L. grown in nutrient solution with variation in N, P, K and Mg levels

    Directory of Open Access Journals (Sweden)

    E.F.S. David

    2014-03-01

    Full Text Available Mentha piperita L. is an aromatic and medicinal species of the family Lamiaceae, known as mint or peppermint, and its leaves and branches produce essential oil rich in menthol. This study aimed to evaluate physiological indexes, macro- and micronutrients inthe shootsand essential oil of Mentha piperita L. grown in nutrient solution number 2 of Hoagland and Arnon (1950 with different N, P, K and Mg levels. Shoot length, dry mass of the different organs, total dry mass, leaf area, essential oil yield and composition, and macronutrient (N, P, K, Mg, Ca, S and micronutrient (Mn, Cu, Fe, Zn contents in the shoot were evaluated. Plants treated with 65%N/50%P/25%K/100%Mg had a tendency towards longer shoot, greaterroot and leaf blade dry masses, higher essential oil yield, higher menthol levels and lower menthone levels. The results showed that Mentha can be grown in nutrient solution by reducing 65% N, 50% P, 25% K and 100% Mg. This solution had better development compared to the other tested treatments. Therefore,we recommendMentha piperita L. to be grown with such nutrient levels.

  3. Alternative growth and defensive strategies reveal potential and gender specific trade-offs in dioecious plants Salix paraplesia to nutrient availability

    Directory of Open Access Journals (Sweden)

    Hao Jiang

    2016-07-01

    Full Text Available Population sex ratios of many dioecious plants in nature are biased. This may be attributed to sexually different resource demands and adaptive capacity. In male-biased Populus, males often display stronger physiological adaptation than females. Interestingly, Populus and Salix, belonging to Salicaceae, display an opposite biased sex ratio, especially in nutrient-poor environmental conditions. Do female willows have a greater tolerance to nutrient deficiency than males? In this study, we investigated the growth and defensive strategies of Salix paraplesia cuttings, which were grown with high and low soil fertility for about 140 days over one growing season. Results suggest that different strategies for biomass allocation may result in sexually different defence capacities and trade-offs between growth and defence. Females are likely to adopt radical strategies, overdrawing on available resources to satisfy both growth and defence, which seems to be more like a gamble compared with males. It is also suggested that females may have an extra mechanism to compensate for the investment in growth under nutrient-poor conditions. In summary, the results may help focus restoration efforts on sex selection such that a moderate increase in female willow quantity could increase the resistance and resilience of willow populations to early sporadic desertification.

  4. Alternative Growth and Defensive Strategies Reveal Potential and Gender Specific Trade-Offs in Dioecious Plants Salix paraplesia to Nutrient Availability.

    Science.gov (United States)

    Jiang, Hao; Zhang, Sheng; Lei, Yanbao; Xu, Gang; Zhang, Dan

    2016-01-01

    Population sex ratios of many dioecious plants in nature are biased. This may be attributed to sexually different resource demands and adaptive capacity. In male-biasedPopulus, males often display stronger physiological adaptation than females. Interestingly, Populus and Salix, belonging to Salicaceae, display an opposite biased sex ratio, especially in nutrient-poor environmental conditions. Do female willows have a greater tolerance to nutrient deficiency than males? In this study, we investigated the growth and defensive strategies of Salix paraplesia cuttings, which were grown with high and low soil fertility for about 140 days over one growing season. Results suggest that different strategies for biomass allocation may result in sexually different defense capacities and trade-offs between growth and defense. Females are likely to adopt radical strategies, overdrawing on available resources to satisfy both growth and defense, which seems to be more like a gamble compared with males. It is also suggested that females may have an extra mechanism to compensate for the investment in growth under nutrient-poor conditions. In summary, the results may help focus restoration efforts on sex selection such that a moderate increase in female willow quantity could increase the resistance and resilience of willow populations to early sporadic desertification.

  5. Salts and nutrients present in regenerated waters induce changes in water relations, antioxidative metabolism, ion accumulation and restricted ion uptake in Myrtus communis L. plants.

    Science.gov (United States)

    Acosta-Motos, José R; Alvarez, Sara; Barba-Espín, Gregorio; Hernández, José A; Sánchez-Blanco, María J

    2014-12-01

    The use of reclaimed water (RW) constitutes a valuable strategy for the efficient management of water and nutrients in landscaping. However, RW may contain levels of toxic ions, affecting plant production or quality, a very important aspect for ornamental plants. The present paper evaluates the effect of different quality RWs on physiological and biochemical parameters and the recovery capacity in Myrtus communis L. plants. M. communis plants were submitted to 3 irrigation treatments with RW from different sources (22 weeks): RW1 (1.7 dS m(-1)), RW2 (4.0 dS m(-1)) and RW3 (8.0 dS m(-1)) and one control (C, 0.8 dS m(-1)). During a recovery period of 11 weeks, all plants were irrigated with the control water. The RW treatments did not negatively affect plant growth, while RW2 even led to an increase in biomass. After recovery,only plants irrigated with RW3 showed some negative effects on growth, which was related to a decrease in the net photosynthesis rate, higher Na accumulation and a reduction in K levels. An increase in salinity was accompanied by decreases in leaf water potential, relative water content and gas exchange parameters, and increases in Na and Cl uptake. Plants accumulated Na in roots and restricted its translocation to the aerial part. The highest salinity levels produced oxidative stress, as seen from the rise in electrolyte leakage and lipid peroxidation. The use of regenerated water together with carefully managed drainage practices, which avoid the accumulation of salt by the substrate, will provide economic and environmental benefits.

  6. Multiple impacts of the plant growth-promoting rhizobacterium Variovorax paradoxus 5C-2 on nutrient and ABA relations of Pisum sativum.

    Science.gov (United States)

    Jiang, Fan; Chen, Lin; Belimov, Andrey A; Shaposhnikov, Alexander I; Gong, Fan; Meng, Xu; Hartung, Wolfram; Jeschke, Dieter W; Davies, William J; Dodd, Ian C

    2012-11-01

    Resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. To understand further how the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCd)-containing rhizobacterium Variovorax paradoxus 5C-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (ABA) and ABA metabolism were studied in pea (Pisum sativum) plants following rhizosphere bacterial inoculation. Although root architecture was not affected, inoculation increased root and shoot biomass, and stomatal conductance, by 20, 15, and 24%, respectively, and increased N, P, K, Ca, and Mg uptake by 16, 81, 50, 46, and 58%, respectively. P deposition in inoculated plant roots was 4.9 times higher than that in uninoculated controls. Rhizobacterial inoculation increased root to shoot xylem flows and shoot to root phloem flows of K by 1.8- and 2.1-fold, respectively. In control plants, major sinks for K deposition were the roots and upper shoot (43% and 49% of total uptake, respectively), while rhizobacterial inoculation increased K distribution to the lower shoot at the expense of other compartments (xylem, phloem, and upper shoot). Despite being unable to metabolize ABA in vitro, V. paradoxus 5C-2 decreased root ABA concentrations and accumulation by 40-60%. Although inoculation decreased xylem ABA flows, phloem ABA flows increased. Whether bacterial ACCd attenuates root to shoot ABA signalling requires further investigation, since ABA is critical to maintain growth of droughted plants, and ACCd-containing organisms have been advocated as a means of minimizing growth inhibition of plants in drying soil.

  7. Perdas de elementos nutritivos pela erosão: II - Elementos minerais e carbono Plant nutrient losses caused by erosion: II. Minerals and carbon

    Directory of Open Access Journals (Sweden)

    F. Grohmann

    1956-01-01

    Full Text Available No presente trabalho procurou-se conhecer as perdas por erosão, dos elementos minerais e carbono na terra-roxa-misturada, quando submetida a práticas agrícolas diversas. Com essa finalidade foram usados coletores de enxurrada, do tipo Geib. No material sólido arrastado pela erosão, como também na enxurrada, foram feitas análises químicas dos principais elementos minerais e carbono. Procurou-se, também, estudar as relações entre a quantidade de material arrastado e volume de enxurrada com a composição química desses mesmos materiais. Procurou-se verificar a influência das diversas práticas agrícolas na composição da enxurrada, bem como a influência do material sólido em suspensão, na composição química da enxurrada.The losses of mineral nutrients caused by erosion in plots submitted to different farming practices was studied. The runoff and transported soil were collected by means of a Geib measuring device and then analysed chemically. The results indicated that the amount of nutrients lost by erosion from the plots that received the various farming practices was not affected by the treatments, but were proportional to the total amount of transported soil and to the total volume of runoff. A greater amount of plant nutrients was lost in the form of transported soil than dissolved or suspended in the runoff. The concentration of nutrients in the runoff was not correlated to its volume, except for calcium. The analyses of samples of transported soil and runoff, collected after a few rains, allow a good estimate of the annual losses to be made.

  8. Water relations, nutrient content and developmental responses of Euonymus plants irrigated with water of different degrees of salinity and quality.

    Science.gov (United States)

    Gómez-Bellot, María José; Alvarez, Sara; Castillo, Marco; Bañón, Sebastián; Ortuño, María Fernanda; Sánchez-Blanco, María Jesús

    2013-07-01

    For 20 weeks, the physiological responses of Euonymus japonica plants to different irrigation sources were studied. Four irrigation treatments were applied at 100 % water holding capacity: control (electrical conductivity (EC) plants were rewatered with the same amount and quality of irrigation water as the control plants. Despite the differences in the chemical properties of the water used, the plants irrigated with NaCl and WW showed similar alterations in growth and size compared with the control even at the end of the recovery period. Leaf number was affected even when the EC of the irrigation water was of 1.7 dS m(-1) (IW), indicating the salt sensitivity of this parameter. Stomatal conductance (gs) and photosynthesis (Pn), as well as stem water potential (Ψstem), were most affected in plants irrigated with the most saline waters (NaCl and WW). At the end of the experiment the above parameters recovered, while IW plants showed similar values to the control. The higher Na(+) and Cl(+) uptake by NaCl and WW plants led them to show osmotic adjustment throughout the experiment. The highest amount of boron found in WW plants did not affect root growth. Wastewater can be used as a water management strategy for ornamental plant production, as long as the water quality is not too saline, since the negative effect of salt on the aesthetic value of plants need to be taken into consideration.

  9. Interactions between plants, litter and microbes in cycling of nitrogen and phosphorus in the arctic

    DEFF Research Database (Denmark)

    Jonasson, Sven Evert; Castro, Jorge; Michelsen, Anders

    2006-01-01

    that had been pre-treated by 12 year of warming and fertilizer addition, we incubated soils together with litter and plants added and examined whether the absence of plants and litter in ‘traditional' incubations could explain the discrepancy. The pre-treatment had no effect on nitrogen (N) mineralization...... mineralization in soils without plants. Hence, the presence of plants stimulated mobilization of the growth-limiting N. The growth-sufficient P was not affected by the presence of plants, however. Furthermore, increased plant and microbial N uptake correlated positively, which speaks against competition......Estimated nutrient mineralization in northern nutrient-poor ecosystems, measured as differences in soil inorganic nutrients before and after a period of soil incubation in the absence of plants and litter, usually shows a discrepancy of much lower rates than plant nutrient uptake rates. In plots...

  10. Convergence of a specialized root trait in plants from nutrient-impoverished soils: phosphorus-acquisition strategy in a nonmycorrhizal cactus.

    Science.gov (United States)

    Abrahão, A; Lambers, H; Sawaya, A C H F; Mazzafera, P; Oliveira, R S

    2014-10-01

    In old, phosphorus (P)-impoverished habitats, root specializations such as cluster roots efficiently mobilize and acquire P by releasing large amounts of carboxylates in the rhizosphere. These specialized roots are rarely mycorrhizal. We investigated whether Discocactus placentiformis (Cactaceae), a common species in nutrient-poor campos rupestres over white sands, operates in the same way as other root specializations. Discocactus placentiformis showed no mycorrhizal colonization, but exhibited a sand-binding root specialization with rhizosheath formation. We first provide circumstantial evidence for carboxylate exudation in field material, based on its very high shoot manganese (Mn) concentrations, and then firm evidence, based on exudate analysis. We identified predominantly oxalic acid, but also malic, citric, lactic, succinic, fumaric, and malonic acids. When grown in nutrient solution with P concentrations ranging from 0 to 100 μM, we observed an increase in total carboxylate exudation with decreasing P supply, showing that P deficiency stimulated carboxylate release. Additionally, we tested P solubilization by citric, malic and oxalic acids, and found that they solubilized P from the strongly P-sorbing soil in its native habitat, when the acids were added in combination and in relatively low concentrations. We conclude that the sand-binding root specialization in this nonmycorrhizal cactus functions similar to that of cluster roots, which efficiently enhance P acquisition in other habitats with very low P availability.

  11. Eco-efficient post treatment of digestate from farm and collective biogas plants to improve nutrients (N&P) recycling

    DEFF Research Database (Denmark)

    Trémier, Anne; Béline, Fabrice; Déchaux, Claire

    an opportunity to improve nutrient recycling from organic waste through the development of an eco-effi cient post-treatment system. In this context, LCA was applied to evaluate the sustainability of diff erent raw digestate post-treatment technologies regarding recycling of nutrients from agricultural...... and organic waste to agricultural soils for decreased resource depletion and climate mitigation. Substitution of the use of N and P mineral fertilizers with recycled soil health improver or organic fertilizers products as function of fi ve diff erent post-treatment technologies and raw digestate...... characteristics was evaluated. A particular attention was carried to (1) the gaseous emissions (NH3 and N2O) from process (post-treatment) but also after land spreading and (2) the carbon cycle considering the CO2 carbon costs of fertiliser production and the soil carbon sequestration benefit....

  12. Regulation of 2,4-epibrassinolide on mineral nutrient uptake and ion distribution in Ca(NO3)2 stressed cucumber plants.

    Science.gov (United States)

    Yuan, Lingyun; Zhu, Shidong; Shu, Sheng; Sun, Jin; Guo, Shirong

    2015-09-01

    2,4-Epibrassinolide (EBL) is a plant hormone that plays a pivotal role in regulation of plants growth and development processes under abiotic stress. The investigation was carried out to study the effect of EBL on mineral nutrients uptake and distribution with ion element analysis and X-ray microanalysis in cucumber seedlings (Cucumis sativus L. cv. Jinyou No.4) under 80 mM Ca(NO3)2 stress. Our study found EBL significantly alleviated the inhibitory of P, K, Na, Mg, Fe, Mn, or Cl uptake in shoot or root by Ca(NO3)2 stress. Under Ca(NO3)2 stress, X-ray microanalysis showed that high levels of Ca by EBL treatment accumulated in the epidermal cells of root and gradually decreased from epidermal cells to stellar parenchyma. K(+) levels were restored in different cross section of roots and high K(+) level mostly accumulated in stellar parenchyma. The results of Ca(2+) ultra-structural localization showed Ca(2+) particles of antimonite precipitate by EBL were partly decreased in mesophyll and root cells, and Ca(2+) precipitate distributed in intercellular spaces again. Increased Ca(2+)-ATPase activity and ATP content by EBL were also contributed to extrude excess Ca(2+) from the cytoplasm. These results suggested that EBL could alleviate the ion damage from excess Ca(2+) through regulating mineral nutrients uptake and distribution. Copyright © 2015 Elsevier GmbH. All rights reserved.

  13. Mixing effects of understory plant litter on decomposition and nutrient release of tree litter in two plantations in Northeast China.

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    Full Text Available Understory vegetation plays a crucial role in carbon and nutrient cycling in forest ecosystems; however, it is not clear how understory species affect tree litter decomposition and nutrient dynamics. In this study, we examined the impacts of understory litter on the decomposition and nutrient release of tree litter both in a pine (Pinus sylvestris var. mongolica and a poplar (Populus × xiaozhuanica plantation in Northeast China. Leaf litter of tree species, and senesced aboveground materials from two dominant understory species, Artemisia scoparia and Setaria viridis in the pine stand and Elymus villifer and A. sieversiana in the poplar stand, were collected. Mass loss and N and P fluxes of single-species litter and three-species mixtures in each of the two forests were quantified. Data from single-species litterbags were used to generate predicted mass loss and N and P fluxes for the mixed-species litterbags. In the mixture from the pine stand, the observed mass loss and N release did not differ from the predicted value, whereas the observed P release was greater than the predicted value. However, the presence of understory litter decelerated the mass loss and did not affect N and P releases from the pine litter. In the poplar stand, litter mixture presented a positive non-additive effect on litter mass loss and P release, but an addition effect on N release. The presence of understory species accelerated only N release of poplar litter. Moreover, the responses of mass loss and N and P releases of understory litter in the mixtures varied with species in both pine and poplar plantations. Our results suggest that the effects of understory species on tree litter decomposition vary with tree species, and also highlight the importance of understory species in litter decomposition and nutrient cycles in forest ecosystems.

  14. The use of mobile devices as means of data collection in supporting elementary school students' conceptual understanding about plants

    Science.gov (United States)

    Zacharia, Zacharias C.; Lazaridou, Charalambia; Avraamidou, Lucy

    2016-03-01

    The purpose of this study was to examine the impact of mobile learning among young learners. Specifically, we investigated whether the use of mobile devices for data collection during field trips outside the classroom could enhance fourth graders' learning about the parts of the flower and their functions, flower pollinators and the process of pollination/fertilization, and the interrelationship between animals and plants, more than students' use of traditional means of data collection. For this purpose, we designed a pre-post experimental design study with two conditions: one in which participants used a mobile device for data collection and another using traditional means (e.g. sketching and note-taking). The sample comprised 48 fourth graders (24 in each condition), who studied the flower, its parts, and their functions. A conceptual test was administered to assess students' understanding before and after instruction. Moreover, the students' science notebooks and accompanying artifacts were used as a data source for examining students' progress during the study's intervention. The conceptual test and notebook data were analyzed statistically, whereas we used open coding for the artifacts. Findings revealed that using mobile devices for data collection enhanced students' conceptual understanding more than using traditional means of data collection.

  15. Litter and nutrient flows in tropical upland forest flooded by a hydropower plant in the Amazonian basin.

    Science.gov (United States)

    Pereira, Guilherme Henrique A; Jordão, Henos Carlos K; Silva, Vanessa Francieli V; Pereira, Marcos Gervasio

    2016-12-01

    Extensive areas in the Brazilian Amazon have been flooded for the construction of hydroelectric dams. However, the water regime of these areas affects the dynamics of igarapés (streams) in adjacent terra firme (upland forests). When the reservoirs are filled, the water levels of streams rise above the normal levels and upland bank forests are flooded. We investigated how this flooding affects the litterfall and nutrient input in the upland forests upstream of a hydroelectric dam reservoir in the Central Amazonia. When the reservoir was filled, the forests were flooded and produced more than twice the litter (8.80Mg·ha(-1)yr(-1)), with three times more leaves (6.36Mg·ha(-1)yr(-1)) than when they were not flooded (4.20 and 1.92Mg·ha(-1)yr(-1), respectively). During flooding, the decomposition rate was four times lower in flooded forests (0.328g·g(-1)yr(-1)) than in control forests (1.460g·g(-1)yr(-1)). Despite this, the flooding did not favor litter or nutrient accumulation. Therefore, dam construction changes the organic matter and nutrient cycling in upland Amazon rainforests. This may influence the important role that they play in organic matter dynamics and could have consequences for the regional carbon balance and, ultimately, global climate. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Prospects for optimizing soil microbial functioning to improve plant nutrient uptake and soil carbon sequestration under elevated CO2

    Science.gov (United States)

    Nie, M.; Pendall, E. G.

    2013-12-01

    Potential to mitigate climate change through increasing plant productivity and its carbon (C) input to soil may be limited by soil nitrogen (N) availability. Using a novel 13C-CO2 and 15N-soil dual labeling method, we investigated whether plant growth-promoting bacteria would interact with atmospheric CO2 concentration to alter plant productivity and soil C storage. We grew Bouteloua gracilis under ambient (380 ppm) or elevated CO2 (700 ppm) in climate-controlled chambers, and plant individuals were grown with or without Pseudomonas fluorescens inoculum, which can produce N catabolic enzymes. We observed that both eCO2 and P. fluorescens increased plant productivity and its C allocation to soil. P. fluorescens relative to eCO2 enhanced plant N uptake from soil organic matter, which highly correlated with soil N enzyme activities and rhizosphere exudate C. More importantly, P. fluorescens increased microbial biomass and deceased specific microbial respiration in comparison with eCO2. These results indicate that application of plant growth-promoting bacteria can increase microbial C utilization efficiency with subsequent N mineralization from soil organic matter, and may improve plant N availability and soil C sequestration. Together, our findings highlight the potential of plant growth-promoting bacteria for global change mitigation by terrestrial ecosystems.

  17. Influence of plant root exudates on the mobility of fuel volatile compounds in contaminated soils.

    Science.gov (United States)

    Balseiro-Romero, María; Kidd, Petra S; Monterroso, Carmela

    2014-01-01

    Vegetation and its associated microorganisms play an important role in the behaviour of soil contaminants. One of the most important elements is root exudation, since it can affect the mobility, and therefore, the bioavailability of soil contaminants. In this study, we evaluated the influence of root exudates on the mobility of fuel derived compounds in contaminated soils. Samples of humic acid, montmorillonite, and an A horizon from an alumi-umbric Cambisol were contaminated with volatile contaminants present in fuel: oxygenates (MTBE and ETBE) and monoaromatic compounds (benzene, toluene, ethylbenzene and xylene). Natural root exudates obtained from Holcus lanatus and Cytisus striatus and ten artificial exudates (components frequently found in natural exudates) were added to the samples, individually and as a mixture, to evaluate their effects on contaminant mobility. Fuel compounds were analyzed by headspace-gas chromatography-mass spectrometry. In general, the addition of natural and artificial exudates increased the mobility of all contaminants in humic acid. In A horizon and montmorillonite, natural or artificial exudates (as a mixture) decreased the contaminant mobility. However, artificial exudates individually had different effects: carboxylic components increased and phenolic components decreased the contaminant mobility. These results established a base for developing and improving phytoremediation processes of fuel-contaminated soils.

  18. Insect herbivory on native and exotic aquatic plants: phosphorus and nitrogen drive insect growth and nutrient release

    NARCIS (Netherlands)

    Grutters, B.M.C.; Gross, E.M.; Bakker, E.S.

    2016-01-01

    Eutrophication and globalisation facilitate the dominance of exotic plants in aquatic ecosystems worldwide. Aquatic omnivores can provide biotic resistance to plant invasions, but little is known about whether obligate aquatic herbivores can do the same. Herbivores such as insects can decimate aquat

  19. Effects of supplemental enzymes on apparent nutrient digestibility in rainbow trout (Oncorhynchus mykiss) fed plant-based diets

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Hjermitslev, Niels Harthøj; Ekmann, Kim Schøn;

    2010-01-01

    on the effects of enzymes in fish feed apart from phytase. Phytase works by hydrolyzing phytic acid, and numerous studies have documented that phytase supplementation increases phosphorus availability in fish fed diets with high inclusion levels of plant proteins. Plant derived proteins are increasingly used...

  20. Matching plant and animal processes to alter nutrient supply in strip-grazed cattle: timing of herbage and fasting allocation.

    Science.gov (United States)

    Gregorini, P; Gunter, S A; Beck, P A

    2008-04-01

    This work aimed to assess the impact of timing of herbage allocation and fasting on patterns of ingestive behavior, herbage intake, ruminal fermentation, nutrient flow to the duodenum, and site and extent of digestion. Treatments were daily herbage allocation in the afternoon (1500 h, AHA), morning (0800 h, MHA), AHA after 20 h of fasting (AHAF), and MHA after 20 h of fasting (MHAF). Four ruminally and duodenally fistulated heifers (279 +/- 99 kg of BW) individually strip-grazed wheat pastures in a Latin-square design. Eating, rumination, and idling behavior were recorded every 2 min, and bite and eating step rates were measured hourly while the heifers were grazing (11 h MHA and AHA; 4 h MHAF and AHAF). Ruminal DM pools were measured 4 times daily (0800, 1200, 1500, and 1900 h) to estimate daily herbage DMI and its pattern. Ruminal fluid was sampled at these same times and also at 2300 h. Duodenal digesta was sampled over 2 d to determine the site of herbage digestibility. Treatments did not affect daily herbage DMI (16.5 g/ kg of BW, SE = 0.0025; P > 0.05). However, they altered the eating pattern; the evening grazing bout of AHA and AHAF was greater (P 0.05) among MHA, MHAF, and AHAF; however, it averaged 970, 40, 300, and 540 g/d, respectively, greater (P 0.05) for MHA, AHA, and AHAF, but was lower for MHAF (P 0.05) within fasted and nonfasted treatments; however, it was greater (P 0.05) among MHA, MHAF, and AHAF, but was greater (P nutrient supply. At the same amount of resource allocation, nutrient supply to grazing cattle can be modified through strategic grazing management.

  1. Synergistic Effects of Plant Growth Promoting Rhizobacteria and Chitosan on In Vitro Seeds Germination, Greenhouse Growth, and Nutrient Uptake of Maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Nadège A. Agbodjato

    2016-01-01

    Full Text Available This study aimed to assess the effects of three plant growth promoting rhizobacteria (PGPR and chitosan either singly or in combination on maize seeds germination and growth and nutrient uptake. Maize seeds were treated with chitosan and bacterial solution. The germination and growth tests were carried out in square Petri dishes and plastic pots. The combination chitosan-A. lipoferum-P. fluorescens has increased the seeds vigor index up to 36.44% compared to the control. In comparison to the control, P. putida has significantly improved root weight (44.84% and germinated seed weight (31.39% whereas chitosan-P. putida has increased the shoot weight (65.67%. For the growth test, the maximal heights (17.66% were obtained by plants treated with the combination A. lipoferum-P. fluorescens-P. putida. Chitosan-P. fluorescens induced the highest increases of leaves per plant (50.09%, aerial (84.66%, and underground biomass (108.77% production. The plants inoculated with A. lipoferum had the large leaf areas with an increase of 54.08%, while combinations P. fluorescens-P. putida and chitosan-A. lipoferum improved the aerial and underground dry matter of plants to 26.35% and 18.18%. The nitrogen content of the plants was increased by chitosan-A. lipoferum-P. fluorescens-P. putida with an increasing of 41.61%. The combination of chitosan and PGPR can be used as biological fertilizers to increase maize production.

  2. Crescimento e acumulação de nutrientes em plantas de taro sob níveis de sombreamento artificial Growth and nutrient accumulation of taro plants under artificial shading levels

    Directory of Open Access Journals (Sweden)

    Fabio Luiz de Oliveira

    2011-09-01

    Full Text Available Foi conduzido um experimento em vasos com solo com o objetivo de avaliar o crescimento e acumulação de nutrientes de plantas de taro (Colacasia esculenta sob níveis de sombreamento artificial. O experimento foi constituído de quatro níveis de sombreamento (0, 25, 50 e 75% de restrição de luz e nove coletas mensais, no delineamento de blocos casualizados em esquema de parcelas subdivididas, com quatro repetições. Os ní