WorldWideScience

Sample records for plant nutrient management

  1. 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

  2. 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.

  3. 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...

  4. 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…

  5. 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…

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Nutrient management in substrate systems

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    Speaking about nutrient solutions in soilless cultivation, different solutions can be discerned. Originally, in soilless culture only one nutrient solution was taken into account, being the solution in the containers in which the plants were grown. Such solutions were intensively moved by air bubbli

  12. Nutrient management in substrate systems

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    Speaking about nutrient solutions in soilless cultivation, different solutions can be discerned. Originally, in soilless culture only one nutrient solution was taken into account, being the solution in the containers in which the plants were grown. Such solutions were intensively moved by air bubbli

  13. 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 ...

  14. 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.

  15. 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...

  16. 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.

  17. Approaches and uncertainties in nutrient budgets; Implications for nutrient management and environmental policies

    NARCIS (Netherlands)

    Oenema, O.; Kros, J.; Vries, de W.

    2003-01-01

    Nutrient budgets of agroecosystems are constructed either (i) to increase the understanding of nutrient cycling, (ii) as performance indicator and awareness raiser in nutrient management and environmental policy, or (iii) as regulating policy instrument to enforce a certain nutrient management

  18. Nutrient management strategies on Dutch dairy farms : an empirical analysis

    NARCIS (Netherlands)

    Ondersteijn, C.J.M.

    2002-01-01

    Key Words: MINAS; nitrogen surplus; phosphate surplus; nutrient efficiency; nutrient productivity; financial consequences; strategic management; perceived environmental uncertainty; nutrient management planning; dairy farming; The Netherlands.Agricultural nutrients are a possible pollutant of (groun

  19. Nutrient management strategies on Dutch dairy farms: an empirical analysis

    NARCIS (Netherlands)

    Ondersteijn, C.J.M.

    2002-01-01

    Key Words: MINAS; nitrogen surplus; phosphate surplus; nutrient efficiency; nutrient productivity; financial consequences; strategic management; perceived environmental uncertainty; nutrient management planning; dairy farming; The Netherlands.

    Agricultural nutrients are a

  20. 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.

  1. 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

  2. Nutrient Management in Recirculating Hydroponic Culture

    Science.gov (United States)

    Bugbee, Bruce

    2004-01-01

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

  3. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer must... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal...

  4. Usefulness of Models in Precision Nutrient Management

    DEFF Research Database (Denmark)

    Plauborg, Finn; Manevski, Kiril; Zhenjiang, Zhou

    Modern agriculture increasingly applies new methods and technologies to increase production and nutrient use efficiencies and at the same time reduce leaching of nutrients and greenhouse gas emissions. GPS based ECa-measurement equipment, ER or EM instrumentations, are used to spatially character...... was critical and difficult. Further several years of historic information on crops and crop management for the given field were needed to take into account nitrogen carry over effects.......Modern agriculture increasingly applies new methods and technologies to increase production and nutrient use efficiencies and at the same time reduce leaching of nutrients and greenhouse gas emissions. GPS based ECa-measurement equipment, ER or EM instrumentations, are used to spatially...... and mineral composition. Mapping of crop status and the spatial-temporal variability within fields with red-infrared reflection are used to support decision on split fertilisation and more precise dosing. The interpretation and use of these various data in precise nutrient management is not straightforward...

  5. 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.

  6. Current Status of Nutrient Management in Hainan Rubber Planting Areas and Improvement Strategies%海南植胶区养分管理现状与改进策略

    Institute of Scientific and Technical Information of China (English)

    王大鹏; 王秀全; 成镜; 何鹏; 韦家少

    2013-01-01

    Fertilizer played an extremely important role on developing the rubber planting industry in China. However, after years of rubber planting production, it faced many serious problems in the planting area, such as difficulties in enhancing the unit area yield, soil nutrients decreasing. Based on those mentioned above, fertilization techniques are now urgent to be upgraded. In this paper, the nutrient management situation was reviewed in Hainan, the nutrient management problems of rubber plantation was discussed, on the basis of what the relevant improvement strategies were proposed.%施肥对我国植胶业的发展起了极其重要的作用,然而经过多年的植胶生产,各植胶区已面临单产提升困难、土壤养分大面积下降和施肥技术亟待提升等重大问题。本文对海南植胶区养分管理现状进行综述,探讨海南胶园养分管理的若干问题,并提出改进策略。

  7. 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.

  8. Usefulness of Models in Precision Nutrient Management

    DEFF Research Database (Denmark)

    Plauborg, Finn; Manevski, Kiril; Zhenjiang, Zhou

    and mineral composition. Mapping of crop status and the spatial-temporal variability within fields with red-infrared reflection are used to support decision on split fertilisation and more precise dosing. The interpretation and use of these various data in precise nutrient management is not straightforward...

  9. 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.

  10. Developing a web-based forecasting tool for nutrient management

    Science.gov (United States)

    Modern nutrient management planning tools provide strategic guidance that, in the best cases, educates farmers and others involved in nutrient management to make prudent management decisions. The strategic guidance provided by nutrient management plans does not provide the day-to-day support require...

  11. The Integrated Role of Water Availability, Nutrient Dynamics, and Xylem Hydraulic Dysfunction on Plant Rooting Strategies in Managed and Natural Ecosystems

    Science.gov (United States)

    Mackay, D. S.; Savoy, P.; Pleban, J. R.; Tai, X.; Ewers, B. E.

    2015-12-01

    Plants adapt or acclimate to changing environments in part by allocating biomass to roots and leaves to strike a balance between water and nutrient uptake requirements on the one hand and growth and hydraulic safety on the other hand. In a recent study examining experimental drought with the TREES model, which couples plant ecophysiology with rhizosphere-and-xylem hydraulics, we hypothesized that the asynchronous nature of soil water availability and xylem repair supported root-to-leaf area (RLA) proportionality that favored long-term survival over short-term carbon gain or water use. To investigate this as a possible general principal of plant adjustment to changing environmental conditions, TREES was modified to allocate carbon to fine and coarse roots organized in ten orders differing in biomass allocated per unit absorbing root area, root lifespan, and total absorbing root area in each of several soil-root zones with depth. The expanded model allowed for adjustment of absorbing root area and rhizosphere volume based on available carbohydrate production and nitrogen (N) availability, resulting in dynamic expansion and contraction of the supply-side of the rhizosphere-plant hydraulics and N uptake capacity in response to changing environmental conditions and plant-environment asynchrony. The study was conducted partly in a controlled experimental setting with six genotypes of a widely grown crop species, Brassica rapa. The implications for forests were investigated in controlled experiments and at Fluxnet sites representing temperate mixed forests, semi-arid evergreen needle-leaf, and Mediterranean biomes. The results showed that the effects of N deficiency on total plant growth was modulated by a relative increase in fine root biomass representing a larger absorbing root volume per unit biomass invested. We found that the total absorbing root area per unit leaf area was consistently lower than that needed to maximize short-term water uptake and carbohydrate gain

  12. 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.

  13. 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

  14. Aquatic Plant Control Research Program. Allelopathic Aquatic Plants for Aquatic Plant Management: A Feasibility Study

    Science.gov (United States)

    1989-10-01

    block number) FIELD GROUP SUB-GROUP Allelopathy "Bioassay . Growth inhibition. Aquatic macrophytes. Biocontrol Lena minor 19. ABSTRACT (Continue on...Bibliography of Aquatic Plant Allelopathy ........ Al 2 ALLELOPATHIC AQUATIC PLANTS FOR AQUATIC PLANT MANAGEMENT; A FEASIBILITY STUDY Introduction Background 1...nutrients, water, and other biotic effects could have overriding effects that appear as competition or allelopathy . These biotic factors must be

  15. 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.

  16. 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.

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. [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.

  2. Nutrient Management practices for enhancing Soybean (Glycine max L. production

    Directory of Open Access Journals (Sweden)

    FARID A. HELLAL

    2013-03-01

    Full Text Available percent protein and 19 percent oil in the seeds. The magnitude of soybean yield losses due to nutrient deficiency also varies among the nutrients. Deficiencies of N, P, Fe, B and S nutrients may cause yield losses up to 10 %, 29-45 %, 22-90 %, 100 % and 16-30 %, respectively, in soybean depending on soil fertility, climate and plant factors. Soil salinity is one of the major limiting factors of soybean production in semiarid regions, and chloride salinity has a more depressive effect on yield than sulphate salinity. The goal of nutrient management is to maximize soybean productivity while minimizing environmental consequences. Balanced and timely nutrient management practices applied for soybean contributes to sustainable growth of yield and quality, influences plant health and reduces environmental risks. Balanced nutrition with mineral fertilizers can assist in integrated pest management to reduce damage from infestations of pests and diseases and save inputs required to control them. Balanced fertilization generates higher profits for the farmers, not necessarily through reduced inputs. The role of education and extension in delivering the upto-date knowledge on nutrient management is crucial, challenging, and continuous. La soya (Glycine max L., es el cultivo de legumbres más importante en el mundo. La magnitud de las pérdidas en el rendimientode la soya debido a deficiencias varía dependiendo de los nutrientes. Las deficiencias de N, P, Fe, B y S pueden causar pérdidas en rendimiento de hasta 10 %, 29-45 %, 22-90 %, 100 % y 16-30 %, respectivamente, en la soya dependiendo de la fertilidad del suelo, clima y factores intrínsecos a las plantas. La textura de los suelos utilizados en el cultivo de soya varía entre arenosa y arcillosa. La salinidad del suelo es uno de los mayores factores limitantes en la producción del cultivo en regiones semiáridas, y la salinidad por cloro tiene un mayor efecto en la disminución del

  3. 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

  4. USA Nutrient managment forecasting via the "Fertilizer Forecaster": linking surface runnof, nutrient application and ecohydrology.

    Science.gov (United States)

    Drohan, Patrick; Buda, Anthony; Kleinman, Peter; Miller, Douglas; Lin, Henry; Beegle, Douglas; Knight, Paul

    2017-04-01

    USA and state nutrient management planning offers strategic guidance that strives to educate farmers and those involved in nutrient management to make wise management decisions. A goal of such programs is to manage hotspots of water quality degradation that threaten human and ecosystem health, water and food security. The guidance provided by nutrient management plans does not provide the day-to-day support necessary to make operational decisions, particularly when and where to apply nutrients over the short term. These short-term decisions on when and where to apply nutrients often make the difference between whether the nutrients impact water quality or are efficiently utilized by crops. Infiltrating rainfall events occurring shortly after broadcast nutrient applications are beneficial, given they will wash soluble nutrients into the soil where they are used by crops. Rainfall events that generate runoff shortly after nutrients are broadcast may wash off applied nutrients, and produce substantial nutrient losses from that site. We are developing a model and data based support tool for nutrient management, the Fertilizer Forecaster, which identifies the relative probability of runoff or infiltrating events in Pennsylvania (PA) landscapes in order to improve water quality. This tool will support field specific decisions by farmers and land managers on when and where to apply fertilizers and manures over 24, 48 and 72 hour periods. Our objectives are to: (1) monitor agricultural hillslopes in watersheds representing four of the five Physiographic Provinces of the Chesapeake Bay basin; (2) validate a high resolution mapping model that identifies soils prone to runoff; (3) develop an empirically based approach to relate state-of-the-art weather forecast variables to site-specific rainfall infiltration or runoff occurrence; (4) test the empirical forecasting model against alternative approaches to forecasting runoff occurrence; and (5) recruit farmers from the four

  5. 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....

  6. 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.

  7. 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...

  8. 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

  9. The potentials of multi-nutrient soil extraction with 0.01 M CaCl2 in nutrient management

    NARCIS (Netherlands)

    Erp, van P.J.

    2002-01-01

     Key words: 0.01 M CaCl 2 , soil testing, nutrient management, decision-making, multi-nutrientAim of this thesis is to improve the understanding of nutrient dynamics in soil and thereby to improve decision-making in nutrient management. There is a need for a more mechanistic

  10. 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.

  11. Effects of Reduced Tillage on Crop Yield, Plant Available Nutrients and Soil Organic Matter in a 12-Year Long-Term Trial under Organic Management

    Directory of Open Access Journals (Sweden)

    Wilhelm Claupein

    2013-09-01

    Full Text Available A field experiment was performed in Southwest Germany to examine the effects of long-term reduced tillage (2000–2012. Tillage treatments were deep moldboard plow: DP, 25 cm; double-layer plow; DLP, 15 + 10 cm, shallow moldboard plow: SP, 15 cm and chisel plow: CP, 15 cm, each of them with or without preceding stubble tillage. The mean yields of a typical eight-year crop rotation were 22% lower with CP compared to DP, and 3% lower with SP and DLP. Stubble tillage increased yields by 11% across all treatments. Soil nutrients were high with all tillage strategies and amounted for 34–57 mg kg−1 P and 48–113 mg kg−1 K (0–60 cm soil depth. Humus budgets showed a high carbon input via crops but this was not reflected in the actual Corg content of the soil. Corg decreased as soil depth increased from 13.7 g kg−1 (0–20 cm to 4.3 g kg−1 (40–60 cm across all treatments. After 12 years of experiment, SP and CP resulted in significantly higher Corg content in 0–20 cm soil depth, compared to DP and DLP. Stubble tillage had no significant effect on Corg. Stubble tillage combined with reduced primary tillage can sustain yield levels without compromising beneficial effects from reduced tillage on Corg and available nutrient content.

  12. Nutrient management regulations in The Netherlands

    NARCIS (Netherlands)

    Schröder, J.J.; Neeteson, J.J.

    2008-01-01

    The application of nutrients affect the quality of the environment which justifies the consideration of regulations regarding their use in agriculture. In the early 1990s The Netherlands decided to use the indicator `nutrient surplus at farm level¿ as the basis for a regulation which was called the

  13. 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.

  14. 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

  15. 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.

  16. Soil testing for P and K has value in nutrient management for annual crops

    Directory of Open Access Journals (Sweden)

    Daniel Geisseler

    2016-08-01

    Full Text Available Adequate nutrients in forms available to plant roots are essential for sustainable crop production. Soil testing for phosphorus and potassium availability allows growers and crop advisers to determine whether a soil is likely to respond to fertilization. As yields have risen with improved management and production systems, crop nutrient demand and the removal of nutrients with harvested crops have increased. An in-depth discussion of soil tests for phosphorus and potassium and their use in California cropping systems is clearly needed. We review how these nutrients become available to plant roots, how samples are taken and test results interpreted, complementary ways to assess the adequacy of supplies and what research is needed to improve soil testing for phosphorus and potassium.

  17. 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

  18. 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.

  19. 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.

  20. Study on Site-specific Nutrient Management in Cotton Field

    Institute of Scientific and Technical Information of China (English)

    YANG Li-ping; JIANG Cheng; JIN Ji-yun; ZHANG Feng-ming

    2001-01-01

    The study on the characteristics of spatial variability of soil nutrients and fertilizer recommendations in cotton field under certain conditions of agricultural management was conducted with GIS and systematic approach for soil nutrient constrains. The results showed that of the spatial variability of soil nutrient was greatly related to the management condition of previous crops. Grid sampling and variable rate application technology (VRAT) were the tools that would hopefully increase fertilizer efficiency. The fertilizers were applied where they were needed and at proper rate. Balance fertilization demonstration showed that fertilizer recommendations according to the available nutrient level in soil could decrease fertilizer cost with 657.4 yuan / ha and increase seed cotton yield by 19.8%. A net profit of the balanced fertilization was 5314.9 yuan / ha higher than that of local fertilization practice.

  1. Short-term forecasting tools for agricultural nutrient management

    Science.gov (United States)

    The advent of real time/short term farm management tools is motivated by the need to protect water quality above and beyond the general guidance offered by existing nutrient management plans. Advances in high performance computing and hydrologic/climate modeling have enabled rapid dissemination of ...

  2. [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.

  3. Biotechnology in plant nutrient management for agricultural ...

    African Journals Online (AJOL)

    SERVER

    2008-03-18

    Mar 18, 2008 ... nutritional profiles and enhanced storage. These are termed as the 1st .... environment), less negative impact on non-target organi- sms, less chemical ... biofertilizers fix atmospheric nitrogen to ammonia by complex metabolic ...

  4. A System for Managing Replenishment of a Nutrient Solution Using an Electrical Conductivity Controller

    Science.gov (United States)

    Davis, D.; Dogan, N.; Aglan, H.; Mortley, D.; Loretan, P.

    1998-01-01

    Control of nutrient solution parameters is very important for the growth and development of plants grown hydroponically. Protocols involving different nutrient solution replenishment times (e.g. one-week, two-week, or two-day replenishment) provide manual periodic control of the nutrient solution's electrical conductivity (EC). Since plants take-up nutrients as they grow, manual control has a drawback in that EC is not held constant between replenishments. In an effort to correct this problem the Center for Food and Environmental Systems for Human Exploration of Space at Tuskegee University has developed a system for managing and controlling levels of EC over a plant's entire growing cycle. A prototype system is being tested on sweetpotato production using the nutrient film technique (NFT), and it is being compared to a system in which sweetpotatoes are grown using NFT with manual control. NASA has played an important role in the development of environmental control systems. They have become a forerunner in growing plants hydroponically with some control systems through the use of networked data acquisition and control using environmental growth chambers. Data acquisition systems which involve the use of real-time, calibration, set points, user panel, and graphical representation programming provide a good method of controlling nutrient solution parameters such as EC and pH [Bledsoe, 19931]. In NASA's Biomass Production Chamber (BPC) at Kennedy Space Center, control is provided by a programmable logic controller (PLC). This is an industrial controller which combines ladder computer logic which has the ability to handle various levels of electrical power. The controller controls temperature, light and other parameters that affect the plant's environment, in the BPC, the Nutrient Delivery System (NIX), a sub-system of the PLC, controls nutrient solution parameters such as EC, pH, and solution levels. When the nutrient EC measurement goes outside a preset range (120

  5. 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

  6. 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.

  7. The potentials of multi-nutrient soil extraction with 0.01 M CaCl2 in nutrient management

    NARCIS (Netherlands)

    Erp, van P.J.

    2002-01-01

    Key words: 0.01 M CaCl 2 , soil testing, nutrient management, decision-making, multi-nutrient

    Aim of this thesis is to improve the understanding of nutrient dynamics in soil and thereby to improve

  8. Sustainable Nutrient Management in Chinese Agriculture:Challenges and Perspective

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    China has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

  9. 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

  10. 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.

  11. 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)

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. Energy production, nutrient recovery and greenhouse gas emission Potentials from Integrated Pig Manure Management Systems

    DEFF Research Database (Denmark)

    Prapaspongsa, Trakarn; Poulsen, Tjalfe; Hansen, Jens Aage

    2010-01-01

    of waste materials were considered. Data for the analyses were obtained from existing waste treatment facilities, experimental plants, laboratory measurements and literature. The assessment reveals that incineration combined with liquid/solid separation and drying of the solids is a promising management......Improper management of pig manure has resulted in environmental problems such as surface water eutrophication, ground water pollution, and greenhouse gas emissions. This study develops and compares 14 alternative manure management scenarios aiming at energy and nutrient extraction. The scenarios...... based on combinations of thermal pretreatment, anaerobic digestion, anaerobic co-digestion, liquid/solid separation, drying, incineration, and thermal gasification were compared with respect to their energy, nutrient and greenhouse gas balances. Both sole pig manure and pig manure mixed with other types...

  1. 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.

  2. Managing sulfur metabolism in plants

    NARCIS (Netherlands)

    Hawkesford, M.J.; De Kok, LJ

    2006-01-01

    Resolution and analysis of genes encoding components of the pathways of primary sulphur assimilation have provided the potential to elucidate how sulphur is managed by plants. Individual roles for members of gene families and regulatory mechanisms operating at gene, cellular and whole plant levels h

  3. 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

  4. 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...

  5. Stakeholder co-development of farm level nutrient management software

    Science.gov (United States)

    Buckley, Cathal; Mechan, Sarah; Macken-Walsh, Aine; Heanue, Kevin

    2013-04-01

    Over the last number of decades intensification in the use nitrogen (N) and phosphorus (P) in agricultural production has lead to excessive accumulations of these nutrients in soils, groundwaters and surface water bodies (Sutton et al., 2011). According to the European Environment Agency (2012) despite some progress diffuse pollution from agriculture is still significant in more than 40% of Europe's water bodies in rivers and coastal waters, and in one third of the water bodies in lakes and transitional waters. Recently it was estimated that approximately 29% of monitored river channel length is polluted to some degree across the Republic of Ireland. Agricultural sources were suspected in 47 per cent of cases (EPA, 2012). Farm level management practices to reduce nutrient transfers from agricultural land to watercourses can be divided into source reduction and source interception approaches (Ribaudo et al., 2001). Source interception approaches involve capturing nutrients post mobilisation through policy instruments such as riparian buffer zones or wetlands. Conversely, the source reduction approach is preventative in nature and promotes strict management of nutrient at farm and field level to reduce risk of mobilisation in the first instance. This has the potential to deliver a double dividend of reduced nutrient loss to the wider ecosystem while maximising economic return to agricultural production at the field and farm levels. Adoption and use of nutrient management plans among farmers is far from the norm. This research engages key farmer and extension stakeholders to explore how current nutrient management planning software and outputs should be developed to make it more user friendly and usable in a practical way. An open innovation technology co-development approach was adopted to investigate what is demanded by the end users - farm advisors and farmers. Open innovation is a knowledge management strategy that uses the input of stakeholders to improve

  6. 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.

  7. 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.

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. Optimal Management of Water, Nutrient and Carbon Cycles of Green Urban Spaces

    Science.gov (United States)

    Revelli, R.; Pelak, N. F., III; Porporato, A. M.

    2016-12-01

    The urban ecosystem is a complex, metastable system with highly coupled flows of mass, energy, people and capital. Their sustainability is in part linked to the existence of green spaces which provide important ecosystem services, whose sustainable management requires quantification of their benefits in terms of impacts on water, carbon and energy fluxes. An exploration of problems of optimal management of such green urban spaces and the related biogeochemical fluxes is presented, extending probabilistic ecohydrological models of the soil-plant system to the urban context, where biophysical and ecological conditions tend to be radically different from the surrounding rural and natural environment (e.g. heat islands, air and water pollution, low quality soils, etc…). The coupled soil moisture, nutrient and plant dynamics are modeled to compute water requirements, carbon footprint, nutrient demand and losses, and related fluxes under different design, management and climate scenarios. The goal is to provide operative rules for a sustainable water use through focused irrigation and fertilization strategies, optimal choice of plants, soil and cultivation conditions, accounting for the typical hydroclimatic variability that occur in the urban environment. This work is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 701914. The work is also cofounded by USDA Agricultural Research Service cooperative agreement 58-6408-3-027; National Science Foundation (NSF) grants: EAR-1331846, EAR-1316258, and the DGE-1068871 and FESD EAR-1338694.

  13. 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

  14. 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

  15. 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

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. Chapter 15. Plant pathology and managing wildland plant disease systems

    Science.gov (United States)

    David L. Nelson

    2004-01-01

    Obtaining specific, reliable knowledge on plant diseases is essential in wildland shrub resource management. However, plant disease is one of the most neglected areas of wildland resources experimental research. This section is a discussion of plant pathology and how to use it in managing plant disease systems.

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. 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

  6. Soil carbon fractions under maize-wheat system: effect of tillage and nutrient management.

    Science.gov (United States)

    Sandeep, S; Manjaiah, K M; Pal, Sharmistha; Singh, A K

    2016-01-01

    Soil organic carbon plays a major role in sustaining agroecosystems and maintaining environmental quality as it acts as a major source and sink of atmospheric carbon. The present study aims to assess the impact of agricultural management practices on soil organic carbon pools in a maize-wheat cropping system of Indo-Gangetic Plains, India. Soil samples from a split plot design with two tillage systems (bed planting and conventional tillage) and six nutrient treatments (T1 = control, T2 = 120 kg urea-N ha(-1), T3 = T2 (25 % N substituted by FYM), T4 = T2 (25 % N substituted by sewage sludge), T5 = T2 + crop residue, T6 = 100 % organic source (50 % FYM + 25 % biofertilizer + 25 % crop residue) were used for determining the organic carbon pools. Results show that there was a significant improvement in Walkley and Black carbon in soil under integrated and organic nutrient management treatments. KMnO4-oxidizable carbon content of soil varied from 0.63 to 1.50 g kg(-1) in soils and was found to be a better indicator for monitoring the impact of agricultural management practices on quality of soil organic carbon than microbial biomass carbon. Tillage and its interaction were found to significantly influence only those soil organic carbon fractions closely associated with aggregate stability viz, labile polysaccharides and glomalin. The highest amount of C4-derived carbon was found to be in plots receiving recommended doses of N as urea (29 %) followed by control plots (25 %). The carbon management index ranged between 82 to 195 and was better in integrated nutrient sources than ones receiving recommended doses of nutrients through mineral fertilizers alone.

  7. Current Soil Nutrient Status of Intensively Managed Greenhouses

    Institute of Scientific and Technical Information of China (English)

    HU Yun-Cai; SONG Zhi-Wen; LU Wen-Long; C.POSCHENRIEDER; U.SCHMIDHALTER

    2012-01-01

    Nine districts covering the main greenhouse vegetable areas in Tianjin Municipality of the North China Plain were selected for the soil investigation in 2010 to survey the current soil nutrient status (soil available N,P and K),acidification and salinization due to excessive input of fertilizers in greenhouses in Tianjin. The study showed that,in particular,soil available P content increased with the age of greenhouses.In contrast,our results did not reveal higher K accumulation and lowered pH in the greenhouse soils compared with cultivation in open fields.Over-fertilization,causing high NO3- accumulation,most likely resulted in salinity problems in the greenhouses.Ninety percent of the investigated greenhouse soils had electrical conductivity values of saturated paste extracts of 2-10 d S m-1,which might affect the yields of vegetable crops like green bean,pepper,cabbage,carrot,eggplant,lettuce,spinach,celery,cucumber and tomato. The findings of our survey of the current fertility and salinity problems in greenhouse soils suggest that there is an urgent need to improve the farmers' practices and strategies in fertilization management in greenhouses of China.Because education and the agricultural technical extension services may play a more important role in avoiding overuse of fertilizers,we suggest that current nutrient management practices should be improved in the near future through training of local farmers in farmers' schools and through strengthening the agricultural extension services with practical techniques.

  8. 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.

  9. 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.

  10. 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.

  11. INTEGRATED APPROACH IN NUTRIENT MANAGEMENT OF SESAME WITH SPECIAL REFERENCE TO ITS YIELD, QUALITY AND NUTRIENT UPTAKE

    OpenAIRE

    SNEHANGSHU SEKHAR NAYEK; KOUSHIK BRAHMACHARI; MD. RITON CHOWDHURY

    2014-01-01

    An experiment on integrated nutrient management practice for augmenting the productivity of sesame (Sesamum indicum) and improving the soil fertility build-up with different quantum of inorganic nutrients (chemical fertilizers) in conjugation with/without organic manure (FYM and neematex) was carried out in Inseptisol soil of New Alluvial zone of West Bengal, India under subtropical climate at Bidhan Chandra Krishi Viswavidyalaya (State Agricultural University) during the summer a...

  12. 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.

  13. 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...

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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...

  20. 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

  1. 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.

  2. 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...

  3. Pathogen reduction co-benefits of nutrient best management practices

    Directory of Open Access Journals (Sweden)

    Jennifer Richkus

    2016-11-01

    Full Text Available Background Many of the practices currently underway to reduce nitrogen, phosphorus, and sediment loads entering the Chesapeake Bay have also been observed to support reduction of disease-causing pathogen loadings. We quantify how implementation of these practices, proposed to meet the nutrient and sediment caps prescribed by the Total Maximum Daily Load (TMDL, could reduce pathogen loadings and provide public health co-benefits within the Chesapeake Bay system. Methods We used published data on the pathogen reduction potential of management practices and baseline fecal coliform loadings estimated as part of prior modeling to estimate the reduction in pathogen loadings to the mainstem Potomac River and Chesapeake Bay attributable to practices implemented as part of the TMDL. We then compare the estimates with the baseline loadings of fecal coliform loadings to estimate the total pathogen reduction potential of the TMDL. Results We estimate that the TMDL practices have the potential to decrease disease-causing pathogen loads from all point and non-point sources to the mainstem Potomac River and the entire Chesapeake Bay watershed by 19% and 27%, respectively. These numbers are likely to be underestimates due to data limitations that forced us to omit some practices from analysis. Discussion Based on known impairments and disease incidence rates, we conclude that efforts to reduce nutrients may create substantial health co-benefits by improving the safety of water-contact recreation and seafood consumption.

  4. 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.

  5. Soil nutrient concentration and distribution at riverbanks undergoing different land management practices: Implications for riverbank management

    Science.gov (United States)

    Xue, X. H.; Chang, S.; Yuan, L. Y.

    2017-08-01

    Riverbanks are important boundaries for the nutrient cycling between lands and freshwaters. This research aimed to explore effects of different land management methods on the soil nutrient concentration and distribution at riverbanks. Soils from the reed-covered riverbanks of middle Yangtze River were studied, including the soils respectively undergoing systematic agriculture (gathering young tender shoots, reaping reed straws, and burning residual straws), fires and no disturbances. Results showed that the agricultural activities sharply decreased the contents of soil organic matter (SOM), N, P and K in subsurface soils but less decreased the surface SOM, N and K contents, whereas phosphorus were evidently decreased at both surface and subsurface layers. In contrast, the single application of fires caused a marked increase of SOM, N, P and K contents in both surface and subsurface soils but had little impacts on soil nutrient distributions. Soils under all the three conditions showed a relative increase of soil nutrients at riverbank foot. This comparative study indicated that the different or even contrary effects of riverbank management practices on soil nutrient statuses should be carefully taken into account when assessing the ecological effects of management practices.

  6. 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

  7. 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.

  8. 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...

  9. 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

  10. Managing Soil Biota-Mediated Decomposition and Nutrient Mineralization in Sustainable Agroecosystems

    Directory of Open Access Journals (Sweden)

    Joann K. Whalen

    2014-01-01

    Full Text Available Transformation of organic residues into plant-available nutrients occurs through decomposition and mineralization and is mediated by saprophytic microorganisms and fauna. Of particular interest is the recycling of the essential plant elements—N, P, and S—contained in organic residues. If organic residues can supply sufficient nutrients during crop growth, a reduction in fertilizer use is possible. The challenge is synchronizing nutrient release from organic residues with crop nutrient demands throughout the growing season. This paper presents a conceptual model describing the pattern of nutrient release from organic residues in relation to crop nutrient uptake. Next, it explores experimental approaches to measure the physical, chemical, and biological barriers to decomposition and nutrient mineralization. Methods are proposed to determine the rates of decomposition and nutrient release from organic residues. Practically, this information can be used by agricultural producers to determine if plant-available nutrient supply is sufficient to meet crop demands at key growth stages or whether additional fertilizer is needed. Finally, agronomic practices that control the rate of soil biota-mediated decomposition and mineralization, as well as those that facilitate uptake of plant-available nutrients, are identified. Increasing reliance on soil biological activity could benefit crop nutrition and health in sustainable agroecosystems.

  11. Woody plants and woody plant management: ecology, safety, environmental impact

    Science.gov (United States)

    James H. Miller

    2001-01-01

    Wise and effective woody plant management is an increasing necessity for many land uses and conservation practices, especially on forests and rangelands where native or exotic plants are affecting productivity, access, or critical habitat. Tools and approaches for managing woody plants have been under concerted development for the past 50 years, integrating mechanical...

  12. Fire management and invasive plants- A handbook

    Science.gov (United States)

    Brooks, Matthew L.; Lusk, Michael

    2008-01-01

    Fire management can help maintain natural habitats, increase forage for wildlife, reduce fuel loads that might otherwise lead to catastrophic wildfire, and maintain natural succession. Today, there is an emerging challenge that fire managers need to be aware of: invasive plants. Fire management activities can create ideal opportunities for invasions by nonnative plants, potentially undermining the benefits of fire management actions. This manual provides practical guidelines that fire managers should consider with respect to invasive plants.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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

  3. 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...

  4. Optimising Cropping Techniques for Nutrient and Environmental Management in Organic Agriculture

    DEFF Research Database (Denmark)

    Köpke, Ulrich; Athmann, Miriam; Han, Eusun;

    2015-01-01

    Depth and architecture of root systems play a prominent role in crop productivity under conditions of low water and nutrient availability. The subsoil contains high amounts of nutrients that may potentially serve for nutrient uptake by crops including finite resources such as phosphorus that have...... to be used in moderation to delay their exhaustion. Biopores are tubular shaped continuous soil pores formed by plant roots and earthworms. Taproot systems especially those of perennial legumes can make soil nutrients plant available from the solid phase and increase the density of vertical biopores...

  5. 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

  6. Advances and challenges for nutrient management in china in the 21st century.

    Science.gov (United States)

    Sims, J T; Ma, L; Oenema, O; Dou, Z; Zhang, F S

    2013-07-01

    Managing agricultural nutrients to provide a safe and secure food supply while protecting the environment remains one of the great challenges for the 21st century. The fourth International Nutrient Management Symposium (INMS), held in 2011 at the University of Delaware, addressed these issues via presentations, panel sessions, and field tours focused on latest technologies and policies available to increase nutrient use efficiency. Participants from the United States, Europe, Canada, and China discussed global trends and challenges, balancing food security and the environment in countries with struggling and emerging economics, nutrient management and transport at the catchment scale, new technologies for managing fertilizer and manure nutrients, and adaptive nutrient management practices for farm to watershed scales. A particular area of interest at the fourth INMS was nutrient management progress and challenges in China over the past 40 years. China's food security challenges and rapidly growing economy have led to major advances in agricultural production systems but also created severe nutrient pollution problems. This special collection of papers from the fourth INMS gives an overview of the remarkable progress China has made in nutrient management and highlights major challenges and changes in agri-environmental policies and practices needed today. Lessons learned in China are of value to both developing and developed countries facing the common task of providing adequate food for an expanding world population, while protecting air and water quality and restoring damaged ecosystems.

  7. 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

  8. [Nutrient management strategy of paddy rice-upland crop rotation system].

    Science.gov (United States)

    Fan, Ming-Sheng; Jiang, Rong-Feng; Zhang, Fu-Suo; Lü, Shi-Hua; Liu, Xue-Jun

    2008-02-01

    Paddy rice-upland crop rotation system is a major cropping system in China, and practiced widely along the Yangtze River basin. A unique feature of this system is the annual conversion of soil from aerobic to anaerobic and then back to aerobic condition, which can result in the changes of soil physical, chemical, and biological prosperities among seasons, making a special agroecosystem. The major challenges faced by this system include declining or stagnating productivity, increasing shortage of irrigation water, improper management of nutrients, low efficiency of resource utilization, and environmental pollution. Based on an overview of the characteristics and problems of paddy rice-upland crop rotation system, this paper put forward a strategy of practicing integrated nutrient management to solve the contradictions between nutrient input, crop production and environmental risk. The key points of this strategy included nutrient management from the whole rotation system perspective, integrated use of nutrients from various sources (chemical fertilizers, organic fertilizers, and nutrients from the environment), synchronization of nutrient supply and crop nutrient demand, application of different management technologies based on the characteristics of different nutrient resources, and integration of nutrient management with other cropping system technologies like water saving and high-yielding cultivation, etc.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Determining Nutrient Requirements For Intensively Managed Loblolly Pine Stands Using the SSAND (Soil Supply and Nutrient Demand) Model

    Science.gov (United States)

    Hector G. Adegbidi; Nicholas B. Comerford; Hua Li; Eric J. Jokela; Nairam F. Barros

    2002-01-01

    Nutrient management represents a central component of intensive silvicultural systems that are designed to increase forest productivity in southern pine stands. Forest soils throughout the South are generally infertile, and fertilizers may be applied one or more times over the course of a rotation. Diagnostic techniques, such as foliar analysis and soil testing are...

  14. Advances and Challenges for Nutrient Management in China in the 21st Century

    NARCIS (Netherlands)

    Sims, J.T.; Ma, L.; Oenema, O.; Dou, Z.; Zhang, F.S.

    2013-01-01

    Managing agricultural nutrients to provide a safe and secure food supply while protecting the environment remains one of the great challenges for the 21st century. The fourth International Nutrient Management Symposium (INMS), held in 2011 at the University of Delaware, addressed these issues via pr

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Principles for ecologically based invasive plant management

    Science.gov (United States)

    Jeremy J. James; Brenda S. Smith; Edward A. Vasquez; Roger L. Sheley

    2010-01-01

    Land managers have long identified a critical need for a practical and effective framework for designing restoration strategies, especially where invasive plants dominate. A holistic, ecologically based, invasive plant management (EBIPM) framework that integrates ecosystem health assessment, knowledge of ecological processes, and adaptive management into a successional...

  7. 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.

  8. 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.

  9. 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.

  10. Microbially produced phytotoxins and plant disease management ...

    African Journals Online (AJOL)

    Microbially produced phytotoxins and plant disease management. ... African Journal of Biotechnology ... Pathogenic fungi and bacteria often damage their host (plants) tissues by producing toxic metabolites, which induced various symptoms ...

  11. 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.

  12. 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...

  13. 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...

  14. 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

  15. 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.

  16. THE INFORMATION CONTENT OF THE FARM AND UNIT LEVEL NUTRIENT BALANCES FOR THE MANAGEMENT

    Directory of Open Access Journals (Sweden)

    T SOMOGYI

    2007-07-01

    Full Text Available The farm gate balance is well known from the environmental literature. This method is not suitable in every case to show the nutrient load for the environment of agricultural companies that is the reason why unit level internal nutrient balances are applied to express the level of nutrient pollution on the environment. These also help to determine the source of the pollution. With the survey of the nutrient flows within the farm we determine the keystones of nutrient management to control the nutrient load of the pollution sources. On the basis of the results and the controlled data of the unit level internal balances we make recommendations for the most appropriate environmental policy instrument to reduce the nutrient pollution.

  17. Proximate versus ultimate limiting nutrients in the Mississippi River Plume and Implications for Hypoxia Reductions through Nutrient Management

    Science.gov (United States)

    Fennel, Katja; Laurent, Arnaud

    2016-04-01

    A large hypoxic area (15,000 km2 on average) forms every summer over the Texas-Louisiana shelf in the northern Gulf of Mexico due to decay of organic matter that is primarily derived from nutrient inputs from the Mississippi/Atchafalaya River System. Efforts are underway to reduce the extent of hypoxic conditions through nutrient management in the watershed; for example, an interagency Hypoxia Task Force is developing Action Plans with input from various stakeholders that set out targets for hypoxia reduction. An open question is how far nutrient loads would have to be decreased in order to produce the desired reductions in hypoxia and when these would be measurable given significant natural variability. We have simulated a large number of multi-year nutrient load reduction scenarios with a regional biogeochemical model for the region. The model is based on the Regional Ocean Modeling System (ROMS), explicitly includes nitrogen (N) and phosphorus (P) species as inorganic nutrients, and has been shown to realistically reproduce the key processes responsible for hypoxia generation. We have quantified the effects of differential reductions in river N and P loads on hypoxic extent. An assessment of the effects of N versus P reductions is important because, thus far, nutrient management efforts have focused on N, yet P is known to limit primary production in spring and early summer. A debate is ongoing as to whether targets for P reductions should be set and whether nutrient reduction efforts should focus solely on P, which results primarily from urban and industrial point sources and is uncoupled from agricultural fertilizer application. Our results strongly indicate that N is the 'ultimate' limiting nutrient to primary production determining the areal extent and duration of hypoxic conditions in a cumulative sense, while P is temporarily limiting in spring. Although reductions in river P load would decrease hypoxic extent in early summer, they would have a much

  18. 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

  19. 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

  20. 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.

  1. Site-Specific Nutrient Management for Rainfed Maize in Western Mid-Hills of Nepal

    Directory of Open Access Journals (Sweden)

    Prakash Ghimire

    2015-06-01

    Full Text Available On-farm experiment was conducted in eight farmers’ field, of Khasyoli village development committee (952 to 1415 masl, Nepal, from April to September, 2011 to address the major constraint (nutrient management to maize production through site-specific nutrient management (SSNM as this approach is popular among scientists. The experiment comprised three nutrient omission plots (0N, 0P, and 0K, an ample NPK plot, and a farmers’ fertilization practice (FFP plot, arranged in randomized complete block design. Farmers planted open pollinated variety (Manakamana-3 and managed in their way. Field-specific NPK application rates were calculated by considering nutrient demand, indigenous NPK supply and recovery efficiency of fertilizers. Grain yield in FFP (2.32 Mg/ha and 0N (1.79 Mg/ha plots differed significantly from each other and rest of the treatments, but was statistically similar among 0P (3.18 Mg/ha, 0K (3.40 Mg/ha and ample NPK (3.38 Mg/ha plots. Post-harvest grain and stover analysis revealed that indigenous NPK supply (20-71 kg N, 19-68 kg P2O5 and 51-164 kg K2O/ha of soil vary among the farmers’ field. Moreover, soil was poor in indigenous N supply (42 kg/ha, but rich in indigenous P2O5 (35 kg/ha and K2O (90 kg/ha supply, on an average. As per the principles of SSNM, the initial fertilizer recommendation made can vary from 40-222 kg N, 0- 93 kg P2O5, and 0-50 kg K2O/ha. On an average, farmers may apply no or lower dose of P2O5 (18 kg/ha and K2O (3 kg/ha but need to significantly increase dose of N (143 kg/ha fertilizer for enhancing soil and maize productivity.

  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. Advances in intergrated nutrient management for crop production in ...

    African Journals Online (AJOL)

    Integrated crop nutrition entails combined use of organic and inorganic fertilizers ... indicated by reduction in bulk density, temperature and conservation of soil moisture. The OMF improved soil organic matter, nutrient content and increased ...

  5. 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.

  6. 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.

  7. A new praxeology for integrated nutrient management, facilitating innovation with and by farmers.

    NARCIS (Netherlands)

    Deugd, M.; Röling, N.G.; Smaling, E.M.A.

    1998-01-01

    Integrated nutrient management (INM) is a broad-based remedy against excessive soil fertility decline or accumulation, problems which are increasingly recognised as major constraints to farming in both temperate and tropical hemispheres. The different technical indicators of INM (nutrient stocks, nu

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Rice (Oryzasativa L.) nutrient management using mycorrhizal fungi and endophyticHerbaspirillum seropedicae

    Institute of Scientific and Technical Information of China (English)

    H Hoseinzade; M R Ardakani; A Shahdi; H Asadi Rahmani; G Noormohammadi; M Miransari

    2016-01-01

    Integrated nutrient management with biological and chemical fertilizers can improve rice (Oryzasativa L.) productivity, bio-fortiifcation, soil health and fertility. Accordingly, this study was planned to evaluate the combined effects of biological fertilizers including arbuscular mycorrhizal (AM) fungi (Glomus mosseae) and free-living nitrogen-ifxing bacteria (Herbaspi-rilum seropedicae), as wel as chemical fertilizers on the yield and nutrient contents of wetland rice under ifeld conditions. Seedlings were inoculated with AM fungi and the bacteria in the nursery and were then transplanted to the ifeld. The experi-ment was carried out as a split factorial design with three replicates. Treatments included three rates of nitrogen (N1, N2 and N3) and phosphorous (P1, P2 and P3) fertilizers (100, 75 and 50% of the optimum level) in the main plots and mycorrhizal and bacterial treatments in the sub plots. The total of urea (g) used per plot was equal to N1=200, N2=150 and N3=100 at three different growth stages (seeding, tilering and heading) and the total of P (g) per plot used once at seeding using triple super phosphate including P1=16, P2=13 and P3=10. Plant growth and yield as wel as the concentration of nitrogen (N), phosphorous (P), potassium (K), iron (Fe), and zinc (Zn) were measured in the soil, straw and grains. N-fertilizer and biological fertilizers had signiifcant effects on root, shoot and grain yield of rice, however, P-fertilizer just signiifcantly affected root and shoot dry weights. Interestingly, analyses of variance indicated that biological fertilization signiifcantly affected al the experimental treatments except straw N. AM fungi, N1 and P1 resulted in the highest rate of rice growth and yield. The interactions of chemical and biological fertilization resulted in signiifcant effects on grain Zn, Fe, P, and N as wel as soil Fe, K and N. The highest rate of grain nutrient uptake was resulted by the combined use of biological fertilization and the

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Nutrient Management in Support of Environmental and Agricultural Sustainability

    Directory of Open Access Journals (Sweden)

    David S. Powlson

    2012-10-01

    Full Text Available Given that we must farm land in order to eat, the total environmental burden imposed by farming a crop, such as winter wheat in the UK, appears to be close to the minimum given current production techniques. The value of the services other than food production, such as flood water buffering, pollination, carbon storage and so on, that land can provide is relatively large compared with the value in reducing environmental burdens from pesticide use, nutrient pollution and greenhouse gas emissions that might arise by farming less intensively. More land will need to be brought into cultivation in order to provide the same amount of food if the intensity of farming is reduced and the resultant loss of ecosystem services (ES outweighs the reduction in other burdens. Nevertheless, losses of nutrients, especially nitrogen (N, from agriculture are a serious concern and the current cost of the environmental footprint of agriculture is significant compared with the value of the food it produces. This article examines nutrient burdens and analyses the means by which the total environmental burden might be reduced relative to productivity. These include increasing the efficiency of farming, removing constraints to yield, and establishing multiple uses for land at the same time as farming. It concludes that agronomic measures which improve nutrient capture and which obtain more yield per unit area are valuable means to avoid degradation of environmental quality because both nutrient pollution and land consumption can be avoided.

  2. 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.

  3. 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.

  4. Fertigation management of potted plants

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    The horticultural crops considered in this chapter are characterised by the fact that the plants are grown in a restricted volume, like pots, containers, plastic trays or compressed peat blocks. In the market these crops are recognized as potted plants, bedding plants and container grown nursery sto

  5. Community implementation dynamics: Nutrient management in the New York City and Chesapeake Bay Watersheds

    Directory of Open Access Journals (Sweden)

    Glenn Earl Sterner

    2015-04-01

    Full Text Available The creation of natural resource management and conservation strategies can be affected by engagement with local citizens and competing interests between agencies and stakeholders at the varying levels of governance. This paper examines the role of local engagement and the interaction between governance levels on the outcomes of nutrient management policy, a specific area of natural resource conservation and management. Presented are two case studies of the New York City and Chesapeake Bay Watersheds in the US. These case studies touch upon the themes of local citizen engagement and governance stakeholder interaction in changing nutrient management to improve water quality. An analysis of these cases leads to several key considerations for the creation and implementation of nutrient management and natural resource management more broadly, including the importance of: local citizen engagement, government brokering and cost sharing; and the need of all stakeholders to respect each other in the policy creation and implementation process.

  6. Community implementation dynamics: Nutrient management in the New York City and Chesapeake Bay Watersheds

    Directory of Open Access Journals (Sweden)

    Glenn Earl Sterner

    2015-04-01

    Full Text Available The creation of natural resource management and conservation strategies can be affected by engagement with local citizens and competing interests between agencies and stakeholders at the varying levels of governance. This paper examines the role of local engagement and the interaction between governance levels on the outcomes of nutrient management policy, a specific area of natural resource conservation and management. Presented are two case studies of the New York City and Chesapeake Bay Watersheds in the US. These case studies touch upon the themes of local citizen engagement and governance stakeholder interaction in changing nutrient management to improve water quality. An analysis of these cases leads to several key considerations for the creation and implementation of nutrient management and natural resource management more broadly, including the importance of: local citizen engagement, government brokering and cost sharing; and the need of all stakeholders to respect each other in the policy creation and implementation process.

  7. Nuclear Power Plant Lifetime Management Study (I)

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sung Yull; Jeong, Ill Seok; Jang, Chang Heui; Song, Taek Ho; Song, Woo Young [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Jin, Tae Eun [Korea Power Engineering Company Consulting and Architecture Engineers, (Korea, Republic of); Kim, Woo Chul [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-12-31

    As the operation-year of nuclear power plant increases and finding sites for new nuclear power plant becomes harder, a comprehensive and systematic nuclear plant lifetime management(PLIM) program including life extension has to be established for stable and safe supply of electricity. A feasibility study was conducted to systematically evaluate technical, economic and regulatory aspect of plant lifetime managements and plant life extension for Kori-1 nuclear power plant. For technical evaluation of nuclear power plant, 13 major components were selected for lifetime evaluation by screening system. structure, and components(SSCs) of the plant. It was found that except reactor pressure vessel, which needs detailed integrity analysis, and low pressure turbine, which is scheduled to be replaced, 11 out of 13 major components have sufficient service life, for more than 40 years. Because domestic rules and regulations related to license renewal has not yet been written, review on the regulatory aspect of life extensions was conducted using US NRC rules and regulations. A cooperative effort with nuclear regulatory body is needed for early completion of license renewal rules and regulations. For economic evaluation of plant lifetime extension, a computer program was developed and used. It was found that 10 to 20 year of extension operation of Kori-1 nuclear power plant was proved. Based on the results, next phase of plant lifetime management program for detailed lifetime evaluation and presenting detailed implementation schedule for plant refurbishment for lifetime extension should be followed. (author). 74 refs., figs.

  8. 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*).

  9. Nutrient cycling for biomass: Interactive proteomic/transcriptomic networks for global carbon management processes within poplar-mycorrhizal interactions

    Energy Technology Data Exchange (ETDEWEB)

    Cseke, Leland [Univ. of Alabama, Huntsville, AL (United States)

    2016-08-30

    This project addresses the need to develop system-scale models at the symbiotic interface between ectomycorrhizal fungi (Laccaria bicolor) and tree species (Populus tremuloides) in response to environmental nutrient availability / biochemistry. Using our now well-established laboratory Laccaria x poplar system, we address the hypothesis that essential regulatory and metabolic mechanisms can be inferred from genomic, transcriptomic and proteomic-level changes that occur in response to environmental nutrient availability. The project addresses this hypothesis by applying state-of-the-art protein-level analytic approaches to fill the gap in our understanding of how mycorrhizal regulatory and metabolic processes at the transcript-level translate to nutrient uptake, carbon management and ultimate net primary productivity of plants. In most cases, these techniques were not previously optimized for poplar trees or Laccaria. Thus, one of the major contributions of this project has been to provide avenues for new research in these species by overcoming the pitfalls that had previously prevented the use of techniques such as ChIP-Seq and SWATH-proteomics. Since it is the proteins that sense and interact with the environment, participate in signal cascades, activate and regulate gene expression, perform the activities of metabolism and ultimately sequester carbon and generate biomass, an understanding of protein activities during symbiosis-linked nutrient uptake is critical to any systems-level approach that links metabolic processes to the environment. This project uses a team of experts at The University of Alabama in Huntsville (UAH), The University of Alabama at Birmingham (UAB) and Argonne National Laboratory (ANL) to address the above hypothesis using a multiple "omics" approach that combines gene and protein expression as well as protein modifications, and biochemical analyses (performed at Brookhaven National Laboratory (BNL)) in poplar trees under mycorrhizal and

  10. 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.

  11. CHARACTERIZING THE SOIL FOR IMPROVED NUTRIENT MANAGEMENT IN SELECTED MAIZE GROWING AREAS OF INDONESIA

    Directory of Open Access Journals (Sweden)

    Achmad I. Fauzi

    2011-04-01

    Full Text Available The demand for maize, the second most important food crop in Indonesia, is steadily increasing. Knowledge of soil properties is a key element in developing nutrient management system. The aims of this study were to characterize and classify the soils at the family level of Soil Taxonomy and linking the taxa with nutrient management systems. The study was conducted at the Site Specific Nutrient Management (SSNM for maize in Indonesia from June to October 2005. Eight soil profiles were taken from Karo (North Sumatra, Sidomulyo (Lampung, Wonogiri and Grobogan (Central Java, Wonokerto, Mojoayu, and Tuban (East Java, and Jeneponto (South Sulawesi. The soil samples were analyzed for their physical, chemical, and mineralogical characteristics. Soil profile description followed the Standard Guidelines of the Food and Agriculture Organiza-tion. Results showed that the sites for the SSNM represented a wide range of soils and climate characteristics from Entisols with 1,050 mm annual rainfall in Jeneponto to Oxisols with 2,200 mm annual rainfall in Lampung. Most soils had a fine texture class (clay and clay loam, but in places like Lampung and Wonogiri, the clay had a low activity leading to a low cation exchange capacity (CEC and low exchangeable cations, especially K. The relatively high-K status soils were found in Karo, Grobogan, and Tuban sites. Organic matter and, in consequence, total N were relatively low for all SSNM sites. Available P status ranged from low to high. The low available P in Grobogan, Wonokerto, and Mojoayu soils seemed to be related to high pH, while in Lampung it was due to low pH. Exchangeable Ca and Mg were high in Grobogan, Mojoayu, Karo, and Tuban due to the presence of weatherable minerals such as hypersthene, augite, and hornblende. In general, this study suggests that organic matter, N, and P will be needed across the sites. K addition will be necessary for Karo, Lampung and Wonogiri, while in other SSNM areas, maintenance

  12. 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.

  13. 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...

  14. 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.

  15. 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...

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. Operational management in pot plant production

    NARCIS (Netherlands)

    Leutscher, K.J.

    1995-01-01

    Operational management in pot plant production was investigated by means of system analysis and simulation. A theoretical framework for operational decision-making consisted of elaboration decisions, progress decisions, and adoption decisions. This framework was incorporated in a pot plant

  1. Erythroneura lawsoni abundance and feeding injury levels are influenced by foliar nutrient status in intensively managed American sycamore.

    Energy Technology Data Exchange (ETDEWEB)

    Coyle, David, Robert: Aubrey, Doug, Patric; Bentz, Jo-Ann

    2010-01-01

    Abstract 1 Abundance and feeding injury of the leafhopper Erythroneura lawsoni Robinson was measured in an intensively-managed American sycamore Platanus occidentalis L. plantation. Trees were planted in spring 2000 in a randomized complete block design, and received one of three annual treatments: (i) fertilization (120 kg N/ha/year); (ii) irrigation (3.0 cm/week); (iii) fertilization + irrigation; or (iv) control (no treatment). 2 Foliar nutrient concentrations were significantly influenced by the treatments because only sulphur and manganese levels were not statistically greater in trees receiving fertilization. 3 Over 116 000 E. lawsoni were captured on sticky traps during the study. Leafhopper abundance was highest on nonfertilized trees for the majority of the season, and was positively correlated with foliar nutrient concentrations. Significant temporal variation in E. lawsoni abundance occurred, suggesting five discrete generations in South Carolina. 4 Significant temporal variation occurred in E. lawsoni foliar injury levels, with the highest injury ratings occurring in late June and August. Foliar injury was negatively correlated with foliar nutrient content, and higher levels of injury occurred more frequently on nonfertilized trees. 5 The results obtained in the present study indicated that increased E. lawsoni abundance occurred on trees that did not receive fertilization. Nonfertilized trees experienced greater foliar injury, suggesting that lower foliar nutrient status may have led to increased levels of compensatory feeding.

  2. Quantifying and managing food-sourced nutrient metabolism in Chinese cities.

    Science.gov (United States)

    Lin, Tao; Wang, Jin; Bai, Xuemei; Zhang, Guoqin; Li, Xinhu; Ge, Rubing; Ye, Hong

    2016-09-01

    Food supply and consumption are critical for sustaining urban system functions, and are key determinants of the quantity and pathways of nutrient flow in cities. Nutrient elements from urban food consumption are becoming major pollutant sources in urban environments. Therefore, understanding flow magnitude and pathways, the role of a growing population, and changing dietary structure and technology in future nutrient metabolism are essential to understand cities as ecosystems and urban environmental management. Taking the city of Xiamen, a rapid urbanizing area of Southeast China as a case study, we simulated urban metabolism of three major food-sourced nutrient elements (carbon, nitrogen, and phosphorus or CNP) over 1991-2010 and environmental emissions. Impacts of future population growth, dietary habit change, and waste treatment improvement on various environments were forecast by scenario analysis. A sensitivity analysis was conducted to test how different waste treatment technologies affect environmental emissions from food-sourced nutrients. Our results show that the food-sourced CNP had various metabolic fluxes through urban systems, with carbon mostly emitted into the air and nitrogen and phosphorus mostly discharged into landfills and water. Population growth and dietary structure change will accelerate increases of nutrient emissions to the environment, whereas enhancing current waste treatment technology can just alter emissions to different environments. Based on the results, we discuss how food-sourced nutrient metabolism can be better managed, to enhance connectivity between cities and their hinterlands and maintain environmental emissions within the carrying capacity of the cities.

  3. Fertility management and landscape position: farmers' use of nutrient sources in western Niger and possible improvements

    NARCIS (Netherlands)

    Gandah, M.; Brouwer, J.; Duivenbooden, van N.; Hiernaux, P.

    2003-01-01

    Poor millet growth and yields in Niger are commonly attributed to rainfall deficits and low soil nutrient content. Land management by local farmers is done as a function of soil types, crops, and available resources. Farmer management practices in millet fields located on four different landscape

  4. 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

  5. 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

  6. 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.

  7. Decadal and seasonal trends of nutrient concentration and export from highly managed coastal catchments.

    Science.gov (United States)

    Wan, Yongshan; Wan, Lei; Li, Yuncong; Doering, Peter

    2017-05-15

    Understanding anthropogenic and hydro-climatic influences on nutrient concentrations and export from highly managed catchments often necessitates trend detection using long-term monitoring data. This study analyzed the temporal trend (1979-2014) of total nitrogen (TN) and total phosphorus (TP) concentrations and export from four adjacent coastal basins in south Florida where land and water resources are highly managed through an intricate canal network. The method of integrated seasonal-trend decomposition using LOESS (LOcally weighted regrESSion) was employed for trend detection. The results indicated that long-term trends in TN and TP concentrations (increasing/decreasing) varied with basins and nutrient species, reflecting the influence of basin specific land and water management practices. These long-term trends were intervened by short-term highs driven by high rainfall and discharges and lows associated with regional droughts. Seasonal variations in TP were more apparent than for TN. Nutrient export exhibited a chemostatic behavior for TN from all the basins, largely due to the biogenic nature of organic N associated with the ubiquity of organic materials in the managed canal network. Varying degrees of chemodynamic export was present for TP, reflecting complex biogeochemical responses to the legacy of long-term fertilization, low soil P holding capacity, and intensive stormwater management. The anthropogenic and hydro-climatic influences on nutrient concentration and export behavior had great implications in nutrient loading abatement strategies for aquatic ecosystem restoration of the downstream receiving waterbody. Published by Elsevier Ltd.

  8. NUTRIENT MANAGEMENT PRACTICES FOR ENHANCING SOYBEAN (Glycine max L. PRODUCTION

    Directory of Open Access Journals (Sweden)

    FARID A. HELLAL

    2013-01-01

    Full Text Available La soya (Glycine max L., es el cultivo de legumbres más importante en el mundo. La magnitud de las pérdidas en el rendimiento de la soya debido a deficiencias varía dependiendo de los nutrientes. Las deficiencias de N, P, Fe, B y S pueden causar pérdidas en rendimiento de hasta 10 %, 29-45 %, 22-90 %, 100 % y 16-30 %, respectivamente, en la soya dependiendo de la fertilidad del suelo, clima y factores intrínsecos a las plantas. La textura de los suelos utilizados en el cultivo de soya varía entre arenosa y arcillosa. La salinidad del suelo es uno de los mayores factores limitantes en la producción del cultivo en regiones semiáridas, y la salinidad por cloro tiene un mayor efecto en la disminución del rendimiento que la salinidad por sulfatos. Los granos de soya son una gran fuente de energía que contienen 40 % de proteína y 19 % de aceite. El éxito del manejo de nutrientes es maximizar la productividad del cultivo mientras se minimizan los impactos ambientales. Las prácticas de manejo de nutrientes balan- ceadas y reguladas en el tiempo contribuyen a un crecimiento sostenido del rendimiento y la calidad, influencian la salud de las plantas y reducen los riesgos ambientales. Una nutrición balanceada con fertilizantes minerales puede ayudar en el manejo integrado de plagas para reducir los daños causados por las infestaciones de pestes y enfermedades y reducir los insumos requeridos para su control. Una fertilización balanceada genera mayores ganancias para los agricultores, no necesariamente por reducción de los insumos. El papel de la educación y la extensión en la difusión del conocimiento actual sobre manejo de nutrientes es crucial, desafiante y continuo.

  9. 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.

  10. 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...

  11. 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...

  12. Reducing soil erosion and nutrient loss on sloping land under crop-mulberry management system.

    Science.gov (United States)

    Fan, Fangling; Xie, Deti; Wei, Chaofu; Ni, Jiupai; Yang, John; Tang, Zhenya; Zhou, Chuan

    2015-09-01

    Sloping croplands could result in soil erosion, which leads to non-point source pollution of the aquatic system in the Three Gorges Reservoir Region. Mulberry, a commonly grown cash plant in the region, is traditionally planted in contour hedgerows as an effective management practice to control soil erosion and non-point source pollution. In this field study, surface runoff and soil N and P loss on sloping land under crop-mulberry management were investigated. The experiments consisted of six crop-mulberry treatments: Control (no mulberry hedgerow with mustard-corn rotation); T1 (two-row contour mulberry with mustard-corn rotation); T2 (three-row contour mulberry with mustard-corn rotation); T3 (border mulberry and one-row contour mulberry with mustard-corn rotation); T4 (border mulberry with mustard-corn rotation); T5 (two-row longitudinal mulberry with mustard). The results indicated that crop-mulberry systems could effectively reduce surface runoff and soil and nutrient loss from arable slope land. Surface runoff from T1 (342.13 m(3) hm(-2)), T2 (260.6 m(3) hm(-2)), T3 (113.13 m(3) hm(-2)), T4 (114 m(3) hm(-2)), and T5 (129 m(3) hm(-2)) was reduced by 15.4, 35.6, 72.0, 71.8, and 68.1%, respectively, while soil loss from T1 (0.21 t hm(-2)), T2 (0.13 t hm(-2)), T3 (0.08 t hm(-2)), T4 (0.11 t hm(-2)), and T5 (0.12 t hm(-2)) was reduced by 52.3, 70.5, 81.8, 75.0, and 72.7%, respectively, as compared with the control. Crop-mulberry ecosystem would also elevate soil N by 22.3% and soil P by 57.4%, and soil nutrient status was contour-line dependent.

  13. Risk and insurance management for biogas plants

    Energy Technology Data Exchange (ETDEWEB)

    Haerig, M. [Marsh GmbH, Duesseldorf (Germany)

    2007-07-01

    The continuing negative experiences of insurers with biogas plants make it difficult for operators to get appropriate insurance cover. There are different reasons for this big number of damages. Especially in the beginning components have been rebuilt for biogas without sufficient experiences. Other damages have emerged due to improper or disregardful plant management. For that reason the insurers' standards for the biogas plant and the plant management have risen up. The following report deals with experiences of insurance for biogas plants and the resulting consequences. For that reason Marsh carried out a research project and analyzed all reported claims in the All Risk Insurance. The necessary technical minimum requirements for installation and operation are geared to the experiences with damages. But they also account for the interests of the insured. (orig.)

  14. 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.

  15. 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.

  16. Relating management practices and nutrient export in agricultural watersheds of the United States

    Science.gov (United States)

    Sprague, Lori A.; Gronberg, Jo Ann M.

    2012-01-01

    Relations between riverine export (load) of total nitrogen (N) and total phosphorus (P) from 133 large agricultural watersheds in the United States and factors affecting nutrient transport were evaluated using empirical regression models. After controlling for anthropogenic inputs and other landscape factors affecting nutrient transport-such as runoff, precipitation, slope, number of reservoirs, irrigated area, and area with subsurface tile drains-the relations between export and the area in the Conservation Reserve Program (CRP) (N) and conservation tillage (P) were positive. Additional interaction terms indicated that the relations between export and the area in conservation tillage (N) and the CRP (P) progressed from being clearly positive when soil erodibility was low or moderate, to being close to zero when soil erodibility was higher, to possibly being slightly negative only at the 90th to 95th percentile of soil erodibility values. Possible explanations for the increase in nutrient export with increased area in management practices include greater transport of soluble nutrients from areas in conservation tillage; lagged response of stream quality to implementation of management practices because of nitrogen transport in groundwater, time for vegetative cover to mature, and/or prior accumulation of P in soils; or limitations in the management practice and stream monitoring data sets. If lags are occurring, current nutrient export from agricultural watersheds may still be reflecting the influence of agricultural land-use practices that were in place before the implementation of these management practices.

  17. Integrated nutrient management research with sweet potato in Papua New Guinea

    NARCIS (Netherlands)

    Hartemink, A.E.

    2003-01-01

    This paper summarizes a series of field experiments that investigated the effects of organic and inorganic nutrients on sweet potato tuber yield in the humid lowlands of Papua New Guinea. In the first experiment, plots were planted with Piper aduncum, Gliricidia sepium and Imperata cylindrica, which

  18. 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.

  19. Development of Information Management System for Plant Life Cycle Management

    Energy Technology Data Exchange (ETDEWEB)

    Byon, SuJin; Lee, SangHyun; Kim, WooJoong [KOREA HYDRO and NUCLEAR POWER CO. LTD, Daejeon (Korea, Republic of)

    2015-10-15

    The study subjects are S. Korean NPP(Nuclear Power Plant) construction projects. Design, construction, operations companies have different nuclear power plant construction project structures, and each company has its own Information Management System. In this study, the end user developed an Information Management System early in the project, and developed a management structure that systematically integrates and interfaces with information in each lifecycle phase. The main perspective of Information Management is moving from the existent document-centric management to the data-centric management. To do so, we intend to integrate information with interfaces among systems. Integrated information management structure and management system are essential for an effective management of the lifecycle information of nuclear power plants that have a lifespan over as much as 80 years. The concept of integration management adopted by the defence, ocean industries or various PLM solution providers is important. Although the NPP project has application systems in each key lifecycle phase, it is more effective to develop and use PLIMS in consideration of the interface and compatibility of information among systems. As an initial study for development of that integrated information management structure, this study is building the system and has interfaced it with a design-stage system.

  20. 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.

  1. 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.

  2. 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....

  3. 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.

  4. 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.

  5. Algorithms for in-season nutrient management in cereals

    Science.gov (United States)

    The demand for improved decision making products for cereal production systems has placed added emphasis on using plant sensors in-season, and that incorporate real-time, site specific, growing environments. The objective of this work was to describe validated in-season sensor based algorithms prese...

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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...

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. AVLIS Production Plant Project Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    1984-11-15

    The AVLIS Production Plant is designated as a Major System Acquisition (in accordance with DOE Order 4240.IC) to deploy Atomic Vapor Laser Isotope Separation (AVLIS) technology at the Oak Ridge, Tennessee site, in support of the US Uranium Enrichment Program. The AVLIS Production Plant Project will deploy AVLIS technology by performing the design, construction, and startup of a production plant that will meet capacity production requirements of the Uranium Enrichment Program. The AVLIS Production Plant Project Management Plan has been developed to outline plans, baselines, and control systems to be employed in managing the AVLIS Production Plant Project and to define the roles and responsibilities of project participants. Participants will develop and maintain detailed procedures for implementing the management and control systems in agreement with this plan. This baseline document defines the system that measures work performed and costs incurred. This plan was developed by the AVLIS Production Plant Project staff of Martin Marietta Energy Systems, Inc. and Lawrence Livermore National Laboratory in accordance with applicable DOE directives, orders and notices. 38 figures, 19 tables.

  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. Distribution Integrity Management Plant (DIMP)

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, Jerome F. [Los Alamos National Laboratory

    2012-05-07

    This document is the distribution integrity management plan (Plan) for the Los Alamos National Laboratory (LANL) Natural Gas Distribution System. This Plan meets the requirements of 49 CFR Part 192, Subpart P Distribution Integrity Management Programs (DIMP) for the LANL Natural Gas Distribution System. This Plan was developed by reviewing records and interviewing LANL personnel. The records consist of the design, construction, operation and maintenance for the LANL Natural Gas Distribution System. The records system for the LANL Natural Gas Distribution System is limited, so the majority of information is based on the judgment of LANL employees; the maintenance crew, the Corrosion Specialist and the Utilities and Infrastructure (UI) Civil Team Leader. The records used in this report are: Pipeline and Hazardous Materials Safety Administration (PHMSA) 7100.1-1, Report of Main and Service Line Inspection, Natural Gas Leak Survey, Gas Leak Response Report, Gas Leak and Repair Report, and Pipe-to-Soil Recordings. The specific elements of knowledge of the infrastructure used to evaluate each threat and prioritize risks are listed in Sections 6 and 7, Threat Evaluation and Risk Prioritization respectively. This Plan addresses additional information needed and a method for gaining that data over time through normal activities. The processes used for the initial assessment of Threat Evaluation and Risk Prioritization are the methods found in the Simple, Handy Risk-based Integrity Management Plan (SHRIMP{trademark}) software package developed by the American Pipeline and Gas Agency (APGA) Security and Integrity Foundation (SIF). SHRIMP{trademark} uses an index model developed by the consultants and advisors of the SIF. Threat assessment is performed using questions developed by the Gas Piping Technology Company (GPTC) as modified and added to by the SHRIMP{trademark} advisors. This Plan is required to be reviewed every 5 years to be continually refined and improved. Records

  7. Fingerponds: managing nutrients and primary productivity for enhanced fish production in Lake Victoria's wetlands, Uganda

    NARCIS (Netherlands)

    Kaggwa, R.C.

    2006-01-01

    Fingerponds are earthen ponds dug at the edge of natural wetlands and stocked naturally with wild fish during flooding. In this study, the management of nutrients and primary productivity in enhancing fish production in these systems is examined in Lake Victorias wetlands, Uganda. Key factors determ

  8. Exploring the Nutrient Release Potential of Organic Materials as Integrated Soil Fertility Management Components Using SAFERNAC

    NARCIS (Netherlands)

    Maro, G.P.; Mrema, J.P.; Msanya, B.M.; Janssen, B.H.; Teri, J.M.

    2014-01-01

    The aim of this study was to establish the nutrient release potential of different organic materials and assess their role in integrated soil fertility management for coffee using the new coffee yield model SAFERNAC. It involved an incubation experiment conducted at TaCRI Lyamungu Screenhouse for

  9. Nutrient management for intensive animal agriculture: policies and practices for sustainability

    NARCIS (Netherlands)

    Sims, J.L.; Bergstrom, L.F.; Bowden, B.T.; Oenema, O.

    2005-01-01

    The intensity of animal production around the world has increased substantially during the last half-century, which has led to large problems with the disposal of manures and waste waters. The focus of this paper is on the development of national policies to improve the nutrient management of

  10. Exploring the Nutrient Release Potential of Organic Materials as Integrated Soil Fertility Management Components Using SAFERNAC

    NARCIS (Netherlands)

    Maro, G.P.; Mrema, J.P.; Msanya, B.M.; Janssen, B.H.; Teri, J.M.

    2014-01-01

    The aim of this study was to establish the nutrient release potential of different organic materials and assess their role in integrated soil fertility management for coffee using the new coffee yield model SAFERNAC. It involved an incubation experiment conducted at TaCRI Lyamungu Screenhouse for 18

  11. Nutrient Management for Eucalypt Plantations in South China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Eucalypts are very popular for revegetation in many parts of south China because of their capacity to tolerate degraded sites and unfertile soils,and their fast growth potential to coppice. This paper reviews a decade of field trials in china, undertaken as part of several bilateral researchprograms in plantation forestry, concerning the use of fertilizers, harvest residue management and inoculation with ectomycorrhizal fungi. One of the key questions addressed is whether the productivity of plantation ...

  12. Energy Management in Industrial Plants

    Directory of Open Access Journals (Sweden)

    Dario Bruneo

    2012-09-01

    Full Text Available The Smart Grid vision imposes a new approach towards energy supply that is more affordable, reliable and sustainable. The core of this new vision is the use of advanced technology to monitor power system dynamics in real time and identify system in stability. In order to implement strategic vision for energy management, it is possible to identify three main areas of investigation such as smart generation, smart grid and smart customer. Focusing on the latter topic, in this paper we present an application specifically designed to monitor an industrial site with particular attention to power consumption. This solution is a real time analysis tool, able to produce useful results to have a strategic approach in the energy market and to provide statistic analysis useful for the future choices of the industrial company. The application is based on a three layers architecture. The technological layer uses a Wireless Sensor Network (WSN to acquire data from the electrical substations. The middleware layer faces the integration problems by processing the raw data. The application layer manages the data acquired from the sensors. This WSN based architecture represents an interesting example of a low cost and non-invasive monitoring application to keep the energy consumption of an industrial site under control. Some of the added value features of the proposed solution are the routing network protocol, selected in order to have an high availability of the WSN, and the use of the WhereX middleware, able to easily implement integration among the different architectural parts.

  13. Farm management, not soil microbial diversity, controls nutrient loss from smallholder tropical agriculture.

    Science.gov (United States)

    Wood, Stephen A; Almaraz, Maya; Bradford, Mark A; McGuire, Krista L; Naeem, Shahid; Neill, Christopher; Palm, Cheryl A; Tully, Katherine L; Zhou, Jizhong

    2015-01-01

    Tropical smallholder agriculture is undergoing rapid transformation in nutrient cycling pathways as international development efforts strongly promote greater use of mineral fertilizers to increase crop yields. These changes in nutrient availability may alter the composition of microbial communities with consequences for rates of biogeochemical processes that control nutrient losses to the environment. Ecological theory suggests that altered microbial diversity will strongly influence processes performed by relatively few microbial taxa, such as denitrification and hence nitrogen losses as nitrous oxide, a powerful greenhouse gas. Whether this theory helps predict nutrient losses from agriculture depends on the relative effects of microbial community change and increased nutrient availability on ecosystem processes. We find that mineral and organic nutrient addition to smallholder farms in Kenya alters the taxonomic and functional diversity of soil microbes. However, we find that the direct effects of farm management on both denitrification and carbon mineralization are greater than indirect effects through changes in the taxonomic and functional diversity of microbial communities. Changes in functional diversity are strongly coupled to changes in specific functional genes involved in denitrification, suggesting that it is the expression, rather than abundance, of key functional genes that can serve as an indicator of ecosystem process rates. Our results thus suggest that widely used broad summary statistics of microbial diversity based on DNA may be inappropriate for linking microbial communities to ecosystem processes in certain applied settings. Our results also raise doubts about the relative control of microbial composition compared to direct effects of management on nutrient losses in applied settings such as tropical agriculture.

  14. Farm management, not soil microbial diversity, controls nutrient loss from smallholder tropical agriculture

    Directory of Open Access Journals (Sweden)

    Stephen A Wood

    2015-03-01

    Full Text Available Tropical smallholder agriculture supports the livelihoods of over 900 million of the world’s poorest people. This form of agriculture is undergoing rapid transformation in nutrient cycling pathways as international development efforts strongly promote greater use of mineral fertilizers to increase crop yields. These changes in nutrient availability may alter the composition of microbial communities with consequences for rates of biogeochemical processes that control nutrient losses to the environment. Ecological theory suggests that altered microbial diversity will strongly influence processes performed by relatively few microbial taxa, such as denitrification and hence nitrogen losses as nitrous oxide, a powerful greenhouse gas. Whether this theory helps predict nutrient losses from agriculture depends on the relative effects of microbial community change and increased nutrient availability on ecosystem processes. We find that mineral and organic nutrient addition to smallholder farms in Kenya alters the taxonomic and functional diversity of soil microbes. However, we find that the direct effects of farm management on both denitrification and carbon mineralization are greater than indirect effects through changes in the taxonomic and functional diversity of microbial communities. Changes in functional diversity are strongly coupled to changes in specific functional genes involved in denitrification, suggesting that it is the expression, rather than abundance, of key functional genes that can serve as an indicator of ecosystem process rates. Our results thus suggest that widely used broad summary statistics of microbial diversity based on DNA may be inappropriate for linking microbial communities to ecosystem processes in certain applied settings. Our results also raise doubts about the relative control of microbial composition compared to direct effects of management on nutrient losses in applied settings such as tropical agriculture.

  15. 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

  16. Farmers' Perception of Integrated Soil Fertility and Nutrient Management for Sustainable Crop Production: A Study of Rural Areas in Bangladesh

    Science.gov (United States)

    Farouque, Md. Golam; Takeya, Hiroyuki

    2007-01-01

    This study aimed to determine farmers' perception of integrated soil fertility and nutrient management for sustainable crop production. Integrated soil fertility (ISF) and nutrient management (NM) is an advanced approach to maintain soil fertility and to enhance crop productivity. A total number of 120 farmers from eight villages in four districts…

  17. Nutrient management for coastal zones: a case study of the nitrogen load to the Stockholm Archipelago.

    Science.gov (United States)

    Scharin, H

    2002-01-01

    This study investigates cost-effective solutions of decreasing the nutrient load to a coastal area, using a drainage basin approach. The study is applied to the Stockholm Archipelago, a coastal area of the Baltic Sea suffering from eutrophication caused by the load of nutrients entering the area. Nitrogen is the nutrient of concern in this study since it is the limiting nutrient of the Archipelago. The main sources of nitrogen are wastewater plants, agriculture, and atmospheric depositions. The final impact of a deposition depends on the buffering capabilities it is subject to on its trajectory from the source to the recipient. This is the reason for using a recipient oriented approach, in which the focus is to reduce the final impact of a deposition. The model integrates data over hydrology, land cover, land use, and economy in order to find the optimal allocation of measures. Results indicate that in order to achieve cost effectiveness, the major part of nitrogen load reduction to the Archipelago should be done at the wastewater plants and by constructing wetlands. The minimum annual cost of reaching a 50% reduction of the load to the Archipelago was estimated to around 191 million Swedish crowns (around $19 million).

  18. 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

  19. 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...

  20. Diagnosis & Correction of Soil Nutrient Limitations in Intensively managed southern pine forests

    Energy Technology Data Exchange (ETDEWEB)

    University of Florida

    2002-10-25

    Forest productivity is one manner to sequester carbon and it is a renewable energy source. Likewise, efficient use of fertilization can be a significant energy savings. To date, site-specific use of fertilization for the purpose of maximizing forest productivity has not been well developed. Site evaluation of nutrient deficiencies is primarily based on empirical approaches to soil testing and plot fertilizer tests with little consideration for soil water regimes and contributing site factors. This project uses mass flow diffusion theory in a modeling context, combined with process level knowledge of soil chemistry, to evaluate nutrient bioavailability to fast-growing juvenile forest stands growing on coastal plain Spodosols of the southeastern U.S. The model is not soil or site specific and should be useful for a wide range of soil management/nutrient management conditions. In order to use the model, field data of fast-growing southern pine needed to be measured and used in the validation of the model. The field aspect of the study was mainly to provide data that could be used to verify the model. However, we learned much about the growth and development of fast growing loblolly. Carbon allocation patterns, root shoot relationships and leaf area root relationships proved to be new, important information. The Project Objectives were to: (1) Develop a mechanistic nutrient management model based on the COMP8 uptake model. (2) Collect field data that could be used to verify and test the model. (3) Model testing.

  1. 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.

  2. Ixcatec ethnoecology: plant management and biocultural heritage in Oaxaca, Mexico

    OpenAIRE

    2016-01-01

    Background Studying motives of plant management allows understanding processes that originated agriculture and current forms of traditional technology innovation. Our work analyses the role of native plants in the Ixcatec subsistence, management practices, native plants biocultural importance, and motivations influencing management decisions. Cultural and ecological importance and management complexity may differ among species according with their use value and availability. We hypothesized t...

  3. Configuration management in nuclear power plants

    CERN Document Server

    2003-01-01

    Configuration management (CM) is the process of identifying and documenting the characteristics of a facility's structures, systems and components of a facility, and of ensuring that changes to these characteristics are properly developed, assessed, approved, issued, implemented, verified, recorded and incorporated into the facility documentation. The need for a CM system is a result of the long term operation of any nuclear power plant. The main challenges are caused particularly by ageing plant technology, plant modifications, the application of new safety and operational requirements, and in general by human factors arising from migration of plant personnel and possible human failures. The IAEA Incident Reporting System (IRS) shows that on average 25% of recorded events could be caused by configuration errors or deficiencies. CM processes correctly applied ensure that the construction, operation, maintenance and testing of a physical facility are in accordance with design requirements as expressed in the d...

  4. Risk management method for small photovoltaic plants

    Directory of Open Access Journals (Sweden)

    Kirova Milena

    2016-09-01

    Full Text Available Risk management is necessary for achieving the goals of the organization. There are many methods, approaches, and instruments in the literature concerning risk management. However, these are often highly specialized and transferring them to a different field can prove difficult. Therefore, managers often face situations where they have no tools to use for risk management. This is the case with small photovoltaic plants (according to a definition by the Bulgarian State Energy and Water Regulatory Commission small applies to systems with a total installed power of 200 kWp. There are some good practices in the energy field for minimizing risks, but they offer only partial risk prevention and are not sufficient. Therefore a new risk management method needs to be introduced. Small photovoltaic plants offer plenty of advantages in comparison to the other renewable energy sources which makes risk management in their case more important. There is no classification of risks for the exploitation of small photovoltaic systems in the available literature as well as to what degree the damages from those risks could spread. This makes risk analysis and evaluation necessary for obtaining information which could aid taking decisions for improving risk management. The owner of the invested capital takes a decision regarding the degree of acceptable risk for his organization and it must be protected depending on the goals set. Investors in small photovoltaic systems need to decide to what degree the existing risks can influence the goals previously set, the payback of the investment, and what is the acceptable level of damages for the investor. The purpose of this work is to present a risk management method, which currently does not exist in the Bulgaria, so that the risks and the damages that could occur during the exploitation of small photovoltaic plants could be identified and the investment in such technology – justified.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. Bespoke microbiome therapy to manage plant diseases

    Directory of Open Access Journals (Sweden)

    Murali eGopal

    2013-12-01

    Full Text Available Advanced biological technologies are revealing that the microbiome, located in gut and rhizosphere, is responsible for maintaining the health of human beings and plants, respectively. Within the complete microbiome a ‘core-microbiome’ exists that plays the pivotal role. Recent studies in medicine have shown that an artificial mixture of bacteria representing the core gut microbiome of healthy person when transferred into gut of diseased person results in re-establishment of normal microflora in the latter leading to alleviation from diseased condition. In agriculture, plant disease management has been achieved through transfer of microbiome by mixing disease suppressive soils with disease conducive soils. However, the exact practice of transferring artificially cultivated core-microbiome as in medicine has not thus far been attempted in plant disease management. Nonetheless, as the gut and rhizosphere microbiome are known to share many common traits, there exists a good scope for accomplishing similar studies in agriculture. Based upon the information in microbiome studies of gut and rhizosphere, we propose that tailor-made core-microbiome transfer therapy can become a viable strategy for management of plant diseases in future.

  16. 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.

  17. Water management requirements for animal and plant maintenance on the Space Station

    Science.gov (United States)

    Johnson, C. C.; Rasmussen, D.; Curran, G.

    1987-01-01

    Long-duration Space Station experiments that use animals and plants as test specimens will require increased automation and advanced technologies for water management in order to free scientist-astronauts from routine but time-consuming housekeeping tasks. The three areas that have been identified as requiring water management and that are discusseed are: (1) drinking water and humidity condensate of the animals, (2) nutrient solution and transpired water of the plants, and (3) habitat cleaning methods. Automation potential, technology assessment, crew time savings, and resupply penalties are also discussed.

  18. Waste Isolation Pilot Plant, Land Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    To reflect the requirement of section 4 of the Wastes Isolation Pilot Plant Land Withdrawal Act (the Act) (Public Law 102-579), this land management plan has been written for the withdrawal area consistent with the Federal Land Policy and Management Act of 1976. The objective of this document, per the Act, is to describe the plan for the use of the withdrawn land until the end of the decommissioning phase. The plan identifies resource values within the withdrawal area and promotes the concept of multiple-use management. The plan also provides opportunity for participation in the land use planning process by the public and local, State, and Federal agencies. Chapter 1, Introduction, provides the reader with the purpose of this land management plan as well as an overview of the Waste Isolation Pilot Plant. Chapter 2, Affected Environment, is a brief description of the existing resources within the withdrawal area. Chapter 3, Management Objectives and Planned Actions, describes the land management objectives and actions taken to accomplish these objectives.

  19. 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

  20. Plant maintenance and outage management issue, 2005

    Energy Technology Data Exchange (ETDEWEB)

    Agnihotri, Newal (ed.)

    2005-01-15

    The focus of the January-February issue is on plant maintenance and outage managment. Major articles/reports in this issue include: Dawn of a new era, by Joe Colvin, Nuclear Energy Institute (NEI); Plant profile: Beloyarsk NPP, Russia, by Nikolai Oshkanov, Beloyarsk NPP, Russia; Improving economic performance, by R. Spiegelberg-Planner, John De Mella, and Marius Condu, IAEA; A model for improving performance, by Pet Karns, MRO Software; ASME codes and standards, by Shannon Burke, ASME International; and, Refurbishment programs, by Craig S. Irish, Nuclear Logistics, Inc.

  1. 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.

  2. Integrated nutrient management (INM) for sustaining crop productivity and reducing environmental impact: A review

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wei, E-mail: weiwu@nwsuaf.edu.cn [College of Agronomy, Northwest A& F University, Yangling, Shaanxi 712100 (China); Agriculture and Agri-Food Canada, Eastern Cereal and Oilseed Research Centre (ECORC), Ottawa, ON K1A 0C6 (Canada); Ma, Baoluo, E-mail: Baoluo.Ma@AGR.GC.CA [Agriculture and Agri-Food Canada, Eastern Cereal and Oilseed Research Centre (ECORC), Ottawa, ON K1A 0C6 (Canada)

    2015-04-15

    The increasing food demands of a growing human population and the need for an environmentally friendly strategy for sustainable agricultural development require significant attention when addressing the issue of enhancing crop productivity. Here we discuss the role of integrated nutrient management (INM) in resolving these concerns, which has been proposed as a promising strategy for addressing such challenges. INM has multifaceted potential for the improvement of plant performance and resource efficiency while also enabling the protection of the environment and resource quality. This review examines the concepts, objectives, procedures and principles of INM. A comprehensive literature search revealed that INM enhances crop yields by 8–150% compared with conventional practices, increases water-use efficiency, and the economic returns to farmers, while improving grain quality and soil health and sustainability. Model simulation and fate assessment further reveal that reactive nitrogen (N) losses and GHG (greenhouse gas) emissions are reduced substantially under advanced INM practices. Lower inputs of chemical fertilizer and therefore lower human and environmental costs (such as intensity of land use, N use, reactive N losses and GHG emissions) were achieved under advanced INM practices without compromising crop yields. Various approaches and perspectives for further development of INM in the near future are also proposed and discussed. Strong and convincing evidence indicates that INM practice could be an innovative and environmentally friendly strategy for sustainable agriculture worldwide. - Highlights: • The increasing pressure to meet global cereal demand poses great challenge. • A changing environment further threatens cereal production. • Literature summary shows 8–150% yield advantage from use of INM method. • INM contributions to mitigation of environmental costs are remarkable. • High crop productivity and less environmental impact can be

  3. Impact of integrated nutrient management on tomato yield under farmers field conditions.

    Science.gov (United States)

    Pandey, S K; Chandra, K K

    2013-11-01

    Field trials were conducted in farmer's field of district Chandauli, Uttar Pradesh, India to assess the impact of integrated nutrient management (INM) on the performance of tomato crop during rabi (2008) and kharif (2009) season. Before conducting trials technological gap between actual and potential productivity were analyzed by interviewing growers to find out the major causes for low yield. Overall gap in use of fertilizers was recorded 64.90 % whereas overall mean gap in technology was 43.83%. On-farm experiments on INM were conducted by applying FYM (10t ha(-1)) + (NPK (150:80:60 kg ha(-1)) followed by dipping seedling roots in 1% Azotobacter solution for 15 min and foliar spray with 20 ppm ferrous ammonium sulphate after 30, 45 and 75 days of transplantation. The plant height, root length, number of primary branches, average fruit weight increased in INM plots as compared to farm practice. The increment in yield was found to be 28.84 and 33.86% during rabi and kharif season respectively. The maximum marketable yield obtained in INM plot during kharif and rabi seasons was 1025 q ha(-1) and 955 q ha(-1) respectively, whereas as farm practice yielded 740 q ha(-1) and 713 q ha(-1) during the same seasons. The percent loss from total production was recorded 8.5 % and 8.8 % in control plot and only 4.9 % and 5.7 % in INM plot during rabi and kharif seasons respectively. The higher fruit weight and lower incidence of disease and pest were observed in INM field in comparison to farm practice. The benefit cost ratio with INM treatment was recorded 4.25 and 4.23 in rabi and kharif season respectively against the benefit cost ratio of 2.98 and 2.82 in control plot during the same respective seasons.

  4. 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

  5. [Spatial variability and management zone of soil major nutrients in tobacco fields in Qiannan mountainous region].

    Science.gov (United States)

    Wu, De-Chuan; Luo, Hong-Xiang; Song, Ze-Min; Guo, Guang-Dong; Chen, Yong-An; Li, Yu-Xiang; Jiang, Yu-Ping; Li, Zhang-Hai

    2014-06-01

    Spatial variability and management zone of soil major nutrients in tobacco fields in Qian-nan mountainous region were analyzed using geostatistics and fuzzy c-mean algorithm. Results indicated that the level of soil organic matter (OM) was moderate, and alkalytic nitrogen (AN), available phosphorus (AP) and available potassium (AK) were rich according to tobacco soil nutrient classification standards. Coefficients of variation (CV) of OM, AN, AP and AK were moderate. Contents of OM, AN, AP and AK fitted log-normal distributions. Correlation analysis showed moderate correlations between OM and AN, AP and AK. OM and AN were best described by Gaussian semivariogram models, while AP and AK were described by exponential models. The four nutrients displayed moderate spatial autocorrelation. There were significant differences among lag distances of four soil nutrients. OM, AN, AP and AK in the majority of studied regions varied at moderate to very rich levels, and deficiencies of OM, AN, AP and AK only accounted for 0.93%, 0.53%, 0.24% and 7.91% of the total studied region, respectively. Based on the results, the studied region was divided into two management zones (MZ), namely MZ1 and MZ2, accounting for 69. 8% and 30. 2% of the studied region respectively. The soil levels of OM, AN, AP and AK in MZ1 were significantly lower than those in MZ2 (P < 0.01).

  6. Cars, Cows, and Checkerspot Butterflies: Nitrogen Deposition and Management of Nutrient-Poor Grasslands for a Threatened Species

    OpenAIRE

    Stuart B Weiss

    1999-01-01

    Nutrient-poor, serpentinitic soils in the San Francisco Bay area sustain a native grassland that supports many rare species, including the Bay checkerspot butterfly ( Euphydryas editha bayensis). Nitrogen (N) deposition from air pollution threatens biodiversity in these grasslands because N is the primary limiting nutrient for plant growth on serpentinitic soils. I investigated the role of N deposition through surveys of butterfly and plant populations across different grazing regimes, by lit...

  7. Bioextraction potential of seaweed in Denmark — An instrument for circular nutrient management

    Energy Technology Data Exchange (ETDEWEB)

    Seghetta, Michele [Research Group on EcoIndustrial System Analysis, Department of Environmental Science, Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, 4000 Roskilde (Denmark); Tørring, Ditte [Orbicon A/S, Jens Juuls Vej 16, 8260 Viby (Denmark); Bruhn, Annette [Department of Bioscience, Faculty of Science and Technology, Aarhus University, Vejlsøvej 25, 8600 Silkeborg (Denmark); Thomsen, Marianne, E-mail: mth@envs.au.dk [Research Group on EcoIndustrial System Analysis, Department of Environmental Science, Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, 4000 Roskilde (Denmark)

    2016-09-01

    The aim of the study is to assess the efficacy of seaweed for circular nutrient management to reduce eutrophication levels in the aquatic environment. We performed a comparative Life Cycle Assessment (LCA) of two reference waste management systems treating seaweed as biowaste, i.e. landfill disposal and combustion, and an alternative scenario using the seaweed Saccharina latissima as a resource for biobased fertilizer production. Life Cycle Impact Assessment (LCIA) methods were improved by using a cradle-to-cradle approach, quantifying fate factors for nitrogen and phosphorus loss from fertilized agriculture to the aquatic environment. We also differentiated between nitrogen- and phosphorus-limited marine water to improve the traditional freshwater impact category, making this indicator suitable for decision support in relation to coastal water management schemes. Offshore cultivation of Saccharina latissima with an average productivity of 150 Mg/km{sup 2} in Danish waters in 2014 was applied to a cultivation scenario of 208 km{sup 2}. The bioresource scenario performs better than conventional biowaste management systems, delivering a net reduction in aquatic eutrophication levels of 32.29 kg N eq. and 16.58 kg PO{sub 4}{sup 3−} eq. per Mg (dry weight) of seaweed, quantified by the ReCiPe and CML impact assessment methods, respectively. Seaweed cultivation, harvest and reuse of excess nutrients from the aquatic environment is a promising approach for sustainable resource cycling in a future regenerative economy that exploits manmade emissions as a resource for closed loop biobased production while significantly reducing eutrophication levels in 3 out of 7 Danish river basin districts. We obtained at least 10% bioextraction of phosphorus manmade emissions (10%, 89% and > 100%) and contributed significantly to local nitrogen reduction goals according to the Water Framework Directive (23%, 78% and > 100% of the target). - Highlights: • Offshore seaweed production

  8. 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.

  9. Nutrient Application and Algal Blooms: Farmer Decisions Regarding the Use of Best Management Practices in Lake Erie's Maumee River Watershed

    Science.gov (United States)

    Heeren, A.; Toman, E.; Wilson, R. S.; Martin, J.

    2016-12-01

    Lake Erie is the most productive of the Great Lakes. However, harmful algal blooms (HABs) caused by nutrient run-off threaten the lake. Experts have proposed numerous best management practices (BMPs) designed to reduce nutrient and sediment run-off. However, for these practices to be effective at reducing HABs, a significant portion of farmers and landowners within Lake Erie's watersheds have to first adopt and implement these practices. In order to better understand how farmers and landowners make decisions about whether or not to adopt and implement BMPs we conducted a series of focus groups and a mail survey of Lake Erie's largest watershed. We found that many farmers were supportive of adopting BMPs. For example, 60% of farmers in the watershed have already adopted using grid soil sampling while another 30% are willing to adopt the practice in the future. However, other practices were less popular, for example, only 18% of farmers had already adopted cover crops. Farmers also expressed several reservations about adopting some BMPs. For example, farmers were concerned about the costs of some BMPs, such as cover crops and drainage management systems, and how such practices might interfere with the planting of subsequent crops. Our research has several implications for reducing nutrient production by promoting BMPs. First, we identified potential concerns and limitations farmers faced in implementing specific BMPs. For example, conservationists can design future programs and communication efforts to target these specific concerns. Second, through examining the socio-psychological and cognitive characteristics that influence farmer decision-making, we identified that willingness to adopt nutrient BMPs is association with how strongly a farmer identifies with conservation and how effective they believed the BMP was at reducing run-off. Messages and information about BMPs may be more effective if they are framed in a way that aligns with identities and beliefs about

  10. In situ Management and Domestication of Plants in Mesoamerica

    National Research Council Canada - National Science Library

    ALEJANDRO CASAS; ADRIANA OTERO-ARNAIZ; EDGAR PÉREZ-NEGRÓN; ALFONSO VALIENTE-BANUET

    2007-01-01

    ... in plant populations under in situ management in the region. • Methods Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria puntila, the tree Leucaena esculenta...

  11. 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

  12. A Risk-Based Approach to Manage Nutrient Contamination From Household Wastewater

    Science.gov (United States)

    Gold, A. J.; Sims, J. T.

    2001-05-01

    Nutrients originating from decentralized wastewater treatment systems (DWTS) can pose a risk to human and ecosystem health. Assessing the likelihood and magnitude of this risk is a formidable and complex challenge. However, a properly constructed risk assessment is essential if we are to design and implement practices for DWTS that minimize the impacts of nutrients on our environment. To do this successfully, we must carefully consider: (i) the specific risks posed by nutrients emitted by DWTS and the sensitivity of humans and ecosystems to these risks; (ii) the pathways by which nutrients move from DWTS to the sectors of the environment where the risk will occur (most often ground and surface waters); (iii) the micro and macro-scale processes that affect the transport and transformations of nutrients once they are emitted from the DWTS and how this in turn affects risk; and (iv) the effects of current or alternative DWTS design and management practices on nutrient transport and subsequent risks to humans and ecosystems. In this paper we examine the risks of nutrients from DWTS to human and ecosystem health at both the micro and the macro?level spatial scales. We focus primarily on the factors that control the movement of N and P from DWTS to ground and surface waters and the research needs related to controlling nonpoint source nutrient pollution from DWTS. At the micro?scale the exposure pathways include the system and the immediate surroundings, i.e., the subsurface environment near the DWTS. The exposed individual or ecosystem at the micro-scale can be a household well, lake, stream or estuary that borders an individual wastewater treatment system. At the macro?level our focus is at the aquifer and watershed scale and the risks posed to downstream ecosystems and water users by nonpoint source pollution of these waters by nutrients from DWTS. We analyze what is known about the effectiveness of current designs at mitigating these risks and our ability to predict

  13. 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

  14. 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

  15. 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...

  16. 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

  17. 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.

  18. 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.

  19. Effects of agricultural nutrient management on nitrogen fate and transport in Lancaster County, Pennsylvania

    Science.gov (United States)

    Hall, D.W.; Risser, D.W.

    1993-01-01

    Nitrogen inputs to, and outputs from, a 55-acre site in Lancaster County, Pennsylvania, were estimated to determine the pathways and relative magnitude of loads of nitrogen entering and leaving the site, and to compare the loads of nitrogen before and after the implementation of nutrient management. Inputs of nitrogen to the site were manure fertilizer, commercial fertilizer, nitrogen in precipitation, and nitrogen in ground-water inflow; and these sources averaged 93, 4, 2, and 1 percent of average annual nitrogen additions, respectively. Outputs of nitrogen from the site were nitrogen in harvested crops, loads of nitrogen in surface runoff, volatilization of nitrogen, and loads of nitrogen in ground-water discharge, which averaged 37, less than 1,25, and 38 percent of average annual nitrogen removals from the site, respectively. Virtually all of the nitrogen leaving the site that was not removed in harvested crops or by volatilization was discharged in the ground water. Applications of manure and fertilizer nitrogen to 47.5 acres of cropped fields decreased about 33 percent, from an average of 22,700 pounds per year (480 pounds per acre per year) before nutrient management to 15,175 pounds of nitrogen per year (320 pounds per acre per year) after the implementation of nutrient management practices. Nitrogen loads in ground-water discharged from the site decreased about 30 percent, from an average of 292 pounds of nitrogen per million gallons of ground water before nutrient management to an average of 203 pounds of nitrogen per million gallons as a result of the decreased manure and commercial fertilizer applications. Reductions in manure and commercial fertilizer applications caused a reduction of approximately 11,000 pounds (3,760 pounds per year, 70 pounds per acre per year) in the load of nitrogen discharged in ground water from the 55-acre site during the three-year period 1987-1990.

  20. 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

  1. 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

  2. Geostatistical approach for management of soil nutrients with special emphasis on different forms of potassium considering their spatial variation in intensive cropping system of West Bengal, India.

    Science.gov (United States)

    Chatterjee, Sourov; Santra, Priyabrata; Majumdar, Kaushik; Ghosh, Debjani; Das, Indranil; Sanyal, S K

    2015-04-01

    indicates reserve native K exploitation under intensive cultivation. These maps highlight the necessity of estimating the other soil K fractions as well for better understanding of soil K supplying capacity and K fertilization strategy rather than the current recommendations, based on the plant-available K alone. In conclusion, the present study revealed that the variability of nutrient distribution was a consequence of complex interactions between the cropping system, nutrient application rates, and the native soil characteristics, and such interactions could be utilized to develop the nutrient management strategies for intensive small-holder system.

  3. Modeling greenhouse gas emissions and nutrient transport in managed arable soils with a fully coupled hydrology-biogeochemical modeling system

    Science.gov (United States)

    Haas, Edwin; Klatt, Steffen; Kiese, Ralf; Butterbach-Bahl, Klaus; Kraft, Philipp; Breuer, Lutz

    2015-04-01

    The use of mineral nitrogen fertilizer sustains the global food production and therefore the livelihood of human kind. The rise in world population will put pressure on the global agricultural system to increase its productivity leading most likely to an intensification of mineral nitrogen fertilizer use. The fate of excess nitrogen and its distribution within landscapes is manifold. Process knowledge on the site scale has rapidly grown in recent years and models have been developed to simulate carbon and nitrogen cycling in managed ecosystems on the site scale. Despite first regional studies, the carbon and nitrogen cycling on the landscape or catchment scale is not fully understood. In this study we present a newly developed modelling approach by coupling the fully distributed hydrology model CMF (catchment modelling framework) to the process based regional ecosystem model LandscapeDNDC for the investigation of hydrological processes and carbon and nitrogen transport and cycling, with a focus on nutrient displacement and resulting greenhouse gas emissions in various virtual landscapes / catchment to demonstrate the capabilities of the modelling system. The modelling system was applied to simulate water and nutrient transport at the at the Yanting Agro-ecological Experimental Station of Purple Soil, Sichuan province, China. The catchment hosts cypress forests on the outer regions, arable fields on the sloping croplands cultivated with wheat-maize rotations and paddy rice fields in the lowland. The catchment consists of 300 polygons vertically stratified into 10 soil layers. Ecosystem states (soil water content and nutrients) and fluxes (evapotranspiration) are exchanged between the models at high temporal scales (hourly to daily) forming a 3-dimensional model application. The water flux and nutrients transport in the soil is modelled using a 3D Richards/Darcy approach for subsurface fluxes with a kinematic wave approach for surface water runoff and the

  4. 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...

  5. 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

  6. The Impact of Agricultural Extension on Farmer Nutrient Management Behavior in Chinese Rice Production: A Household-Level Analysis

    Directory of Open Access Journals (Sweden)

    Dan Pan

    2014-09-01

    Full Text Available Agricultural nutrients play a critical role in food production and human nutrition in China. Against this backdrop, agricultural extension services are essential for providing farmers with knowledge and information about nutrient management. By using a propensity score-matching (PSM approach, this study examines the impact of agricultural extension on farmer nutrient management behavior. Survey data about rice farmers in seven provinces of rural China are used. The empirical results indicate that participation in agricultural extension has a positive impact on rationalizing farmer nutrient management behavior. However, this impact is trivial. Compared with non-participating farmers, the reduced ratio of total fertilizer use and total inorganic fertilizer use by participating farmers is only 1.7% to 3.7%, and the improved ratio of the total organic fertilizer use and the level of soil-testing-based fertilizer use by participating farmers is only 1.008% to 1.173%. Additionally, the causal impacts of agricultural extension participation on nutrient management behavior tend to be higher for more educated, risk-loving and larger-scale farmers. This study reveals that China faces great challenges in implementing improved nutrient management practices for hundreds of millions of farmers through extension services. The findings also have important implications for China’s extension system to meet the objectives of improving nutrient management.

  7. 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 ...

  8. 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.

  9. A simulation model "CTR Dairy" to predict the supply of nutrients in dairy cows managed under discontinuous feeding patterns.

    NARCIS (Netherlands)

    Chilibroste, P.; Dijkstra, J.; Robinson, P.H.; Tamminga, S.

    2008-01-01

    A simulation rumen model has been developed to function under non-steady state conditions in order to allow prediction of nutrient availability in dairy cows managed under discontinuous feeding systems. The model simulates availability of glycogenic, aminogenic and lipogenic nutrients to lactating d

  10. 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.

  11. 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

  12. How do soil quality indicators (SOC and nutrients) change with long-term different crop residue management?

    Science.gov (United States)

    Spiegel, Heide; Lehtinen, Taru; Dersch, Georg; Baumgarten, Andreas

    2016-04-01

    Leaving the crop residues (cereal grain straw, maize stover, sugar beet leaves) on the field may enhance SOC and soil nutrient contents (e.g. P, K, Mg). In contrast, harvesting crop residues for livestock bedding or energy production are often connected with a loss of soil fertility (Lehtinen et al., 2014). We have evaluated the effects of different management of crop residues on selected soil parameters of the upper soil (0-25 cm) in two long-term field experiments in Austria focused on P-dynamics (Marchfeld, since 1982 and Alpenvorland, since 1986). In four P-fertilisation stages (0, 75, 150, 300 kg P2O5 ha-1y-1) all crop residues were incorporated in one treatment and all removed in the other one, respectively. The results show that the effects are different at the two investigated sites. At the site Marchfeld, a medium textured soil, on average SOC was significantly higher with the incorporation of crop residues (21.6 g kg-1) compared to the removal (19.9 g kg-1) after 32 years. In the long run, SOC levels could be maintained, if crop residues remained at the field, whereas the constant removal of crop residues resulted in a SOC decline. At the site Alpenvorland, SOC was only slightly higher with the incorporation of the crop residues after 28 years. In this case, in the long run, even with this management practice and, moreover, with the residue removal, SOC tended to decrease generally. At the Marchfeld, crop residue incorporation resulted in a significant increase of "plant available" phosphorus (P-CAL) only with very high P fertilization. However, "plant available" Mg (according to Schachtschabel) and potassium (K-CAL) were significantly higher in all P fertilisation stages compared to the residue removal treatments. At the site Alpenvorland, the soils are rich in silt and clay and with long-term incorporation of crop residues a significant increase only of „plant available" K of about 50% occurred. This indicates the necessity of taking into account the

  13. 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....

  14. Bioextraction potential of seaweed in Denmark – an instrument for circular nutrient management

    DEFF Research Database (Denmark)

    Seghetta, Michele; Tørring, Ditte; Bruhn, Annette;

    2016-01-01

    The aim of the study is to assess the efficacy of seaweed for circular nutrient management to reduce eutrophication levels in the aquatic environment. We performed a comparative Life Cycle Assessment (LCA) of two reference waste management systems treating seaweed as biowaste, i.e. landfill...... economy that exploits manmade emissions as a resource for closed loop biobased production while significantly reducing eutrophication levels in 3 out of 7 Danish river basin districts. We obtained at least 10% bioextraction of phosphorus manmade emissions (10%, 89% and > 100%) and contributed...

  15. 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

  16. Innovative low cost procedure for nutrient removal as an integrated element of a decentralised water management concept for rural areas.

    Science.gov (United States)

    Burde, M; Rolf, F; Grabowski, F

    2001-01-01

    The absence of large rivers with rather high niveau of self purifying effect in parts of east Germany leads to a discharging of the effluent of wastewater treatment plants into the groundwater in many cases. One useful consequence is the idea of realisation of decentralised measures and concepts in urban water resources management concerning municipal wastewater as well as rainfall, precipitation. At the same time, only the upper soil zone--a few decimetres--is water--saturated and thus discharge effective, even when extreme rainfall takes place. Underneath, however, there generally exists an unsaturated soil zone, which is up to now a rather unexplored retardation element of the hydrologic- and substrate-cycle. Nutrient removal in small wastewater treatment plants that are emptying into ground waters is often beneficial. The presented studies optimised an inexpensive method of subsequent enhanced wastewater treatment. The developed reactor is similar to a concentrated subsoil passage. The fixed bed reactor is divided in two sections to achieve aerobic and anoxic conditions for nitrification/denitrification processes. To enhance phosphorus removal, ferrous particles are put into the aerobic zone. Two series of column tests were carried out and a technical pilot plant was built to verify the efficiency of the process. The results show that this method can be implemented successfully.

  17. Integrated water resources management in central Asia: nutrient and heavy metal emissions and their relevance for the Kharaa River Basin, Mongolia.

    Science.gov (United States)

    Hofmann, J; Venohr, M; Behrendt, H; Opitz, D

    2010-01-01

    Within the framework of Integrated Water Resources Management (IWRM) the nutrient and heavy metal levels within the Kharaa river basin were investigated. By the application of the MONERIS model, which quantifies nutrient emissions into river basins, various point and diffuse pathways, as well as nutrient load in rivers, could be analysed. Despite seasonal variations and inputs of point sources (e.g. Wastewater Treatment Plant Darkhan) the nutrient concentrations in most of the subbasins are on a moderate level. This shows evidence for a nutrient limited ecosystem as well as dilution effects. However, in the middle and lower reaches heavy metal concentrations of arsenic and mercury, which are linked to mining activities in many cases, are a point of concern. Thus measures are necessary to protect the valuable chemical and ecological status of the Kharaa River and its tributaries. As a result of the growing economic pressure Mongolia will enhance the agricultural production by irrigation. Until 2015 about 60% of the agricultural land shall be irrigated. In addition the gold mining activities shall increase by 20% a year. Both sectors have a high demand for water quantity and quality. The model MONERIS allows the assessment of measures which are inevitable to protect the water quality under shrinking water availability.

  18. Science to Improve Nutrient Management Practices, Metrics of Benefits, Accountability, and Communication (Project SSWR 4.03)

    Science.gov (United States)

    This project will demonstrate transferable modeling techniques and monitoring approaches to enable water resource professionals to make comparisons among nutrient reduction management scenarios across urban and agricultural areas. It will produce the applied science to allow bett...

  19. A road to food? : efficacy of nutrient management options targeted to heterogeneous soilscapes in the Teso farming system, Uganda

    NARCIS (Netherlands)

    Ebanyat, P.

    2009-01-01

    Key words: Land use change; Heterogeneity in soil fertility; Targeting; Integrated soil fertility management; Nutrient use efficiencies; Rehabilitation of degraded fields; Fertiliser requirements, Finger millet; QUEFTS model; Smallholder systems; sub-Saharan Africa. Poor soil fertility in smallhol

  20. Food Waste to Energy: An Overview of Sustainable Approaches for Food Waste Management and Nutrient Recycling.

    Science.gov (United States)

    Paritosh, Kunwar; Kushwaha, Sandeep K; Yadav, Monika; Pareek, Nidhi; Chawade, Aakash; Vivekanand, Vivekanand

    2017-01-01

    Food wastage and its accumulation are becoming a critical problem around the globe due to continuous increase of the world population. The exponential growth in food waste is imposing serious threats to our society like environmental pollution, health risk, and scarcity of dumping land. There is an urgent need to take appropriate measures to reduce food waste burden by adopting standard management practices. Currently, various kinds of approaches are investigated in waste food processing and management for societal benefits and applications. Anaerobic digestion approach has appeared as one of the most ecofriendly and promising solutions for food wastes management, energy, and nutrient production, which can contribute to world's ever-increasing energy requirements. Here, we have briefly described and explored the different aspects of anaerobic biodegrading approaches for food waste, effects of cosubstrates, effect of environmental factors, contribution of microbial population, and available computational resources for food waste management researches.

  1. Food Waste to Energy: An Overview of Sustainable Approaches for Food Waste Management and Nutrient Recycling

    Directory of Open Access Journals (Sweden)

    Kunwar Paritosh

    2017-01-01

    Full Text Available Food wastage and its accumulation are becoming a critical problem around the globe due to continuous increase of the world population. The exponential growth in food waste is imposing serious threats to our society like environmental pollution, health risk, and scarcity of dumping land. There is an urgent need to take appropriate measures to reduce food waste burden by adopting standard management practices. Currently, various kinds of approaches are investigated in waste food processing and management for societal benefits and applications. Anaerobic digestion approach has appeared as one of the most ecofriendly and promising solutions for food wastes management, energy, and nutrient production, which can contribute to world’s ever-increasing energy requirements. Here, we have briefly described and explored the different aspects of anaerobic biodegrading approaches for food waste, effects of cosubstrates, effect of environmental factors, contribution of microbial population, and available computational resources for food waste management researches.

  2. Food Waste to Energy: An Overview of Sustainable Approaches for Food Waste Management and Nutrient Recycling

    Science.gov (United States)

    Paritosh, Kunwar; Kushwaha, Sandeep K.; Yadav, Monika; Pareek, Nidhi; Chawade, Aakash

    2017-01-01

    Food wastage and its accumulation are becoming a critical problem around the globe due to continuous increase of the world population. The exponential growth in food waste is imposing serious threats to our society like environmental pollution, health risk, and scarcity of dumping land. There is an urgent need to take appropriate measures to reduce food waste burden by adopting standard management practices. Currently, various kinds of approaches are investigated in waste food processing and management for societal benefits and applications. Anaerobic digestion approach has appeared as one of the most ecofriendly and promising solutions for food wastes management, energy, and nutrient production, which can contribute to world's ever-increasing energy requirements. Here, we have briefly described and explored the different aspects of anaerobic biodegrading approaches for food waste, effects of cosubstrates, effect of environmental factors, contribution of microbial population, and available computational resources for food waste management researches.

  3. [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.

  4. Fertilizer and soil management practices for improving the efficiency of nutrient uptake and use in northern highbush blueberry

    Science.gov (United States)

    Highbush blueberry is a long-lived perennial crop well-adapted to acidic soils. Plants acquire primarily NH4-N and tolerate relatively low concentrations of P and cations in the soil and high concentrations of plant available metals such as Al and Mn. Recently, we found that optimal leaf nutrient co...

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Nutritional management of breastfeeding infants for the prevention of common nutrient deficiencies and excesses

    Directory of Open Access Journals (Sweden)

    Jin Soo Moon

    2011-07-01

    Full Text Available Breastfeeding is the best source of nutrition for every infant, and exclusive breastfeeding for 6 months is usually optimal in the common clinical situation. However, inappropriate complementary feeding could lead to a nutrient-deficient status, such as iron deficiency anemia, vitamin D deficiency, and growth faltering. The recent epidemic outbreak of obesity in Korean children emphasizes the need for us to control children’s daily sedentary life style and their intakes of high caloric foods in order to prevent obesity. Recent assessment of breastfeeding in Korea has shown that the rate is between 63% and 89%; thus, up-to-dated evidence-based nutritional management of breastfeeding infants to prevent common nutrient deficiencies or excesses should be taught to all clinicians and health care providers.

  17. Nutritional management of breastfeeding infants for the prevention of common nutrient deficiencies and excesses.

    Science.gov (United States)

    Moon, Jin Soo

    2011-07-01

    Breastfeeding is the best source of nutrition for every infant, and exclusive breastfeeding for 6 months is usually optimal in the common clinical situation. However, inappropriate complementary feeding could lead to a nutrient-deficient status, such as iron deficiency anemia, vitamin D deficiency, and growth faltering. The recent epidemic outbreak of obesity in Korean children emphasizes the need for us to control children's daily sedentary life style and their intakes of high caloric foods in order to prevent obesity. Recent assessment of breastfeeding in Korea has shown that the rate is between 63% and 89%; thus, up-to-dated evidence-based nutritional management of breastfeeding infants to prevent common nutrient deficiencies or excesses should be taught to all clinicians and health care providers.

  18. Can We Manage Nonpoint-Source Pollution Using Nutrient Concentrations during Seasonal Baseflow?

    Directory of Open Access Journals (Sweden)

    James A. McCarty

    2016-05-01

    Full Text Available Nationwide, a substantial amount of resources has been targeted toward improving water quality, particularly focused on nonpoint-source pollution. This study was conducted to evaluate the relationship between nutrient concentrations observed during baseflow and runoff conditions from 56 sites across five watersheds in Arkansas. Baseflow and stormflow concentrations for each site were summarized using geometric mean and then evaluated for directional association. A significant, positive correlation was found for NO–N, total N, soluble reactive P, and total P, indicating that sites with high baseflow concentrations also had elevated runoff concentrations. Those landscape factors that influence nutrient concentrations in streams also likely result in increased runoff, suggesting that high baseflow concentrations may reflect elevated loads from the watershed. The results highlight that it may be possible to collect water-quality data during baseflow to help define where to target nonpoint-source pollution best management practices within a watershed.

  19. Runoff nutrient and suspended sediment fluxes, cycling, and management in southern Kaneohe Bay, Hawaii

    Science.gov (United States)

    Ringuet, S.; Young, C. W.; Hoover, D. J.; de Carlo, E. H.; MacKenzie, F. T.

    2003-12-01

    -limitation that has been confirmed by nutrient-enrichment experiments. Elevated DIN:DIP values for storm runoff (25) change significantly the proportion of dissolved nutrients available for biological uptake. Significant increases in Chl-a concentrations in the bay a few days after storms suggest that phytoplankton growth was stimulated by the excess nutrients. The extremely low phosphate levels combined with the very high DIN:DIP values in Bay waters imply that phosphorus was the ultimate limiting-nutrient. Therefore, stream runoff has the potential of shifting the "normal" nitrogen-limited environment into a phosphorus-limited ecosystem. This shift has consequences for the management of fluvial nutrient inputs to Kaneohe Bay.

  20. 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.

  1. 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.

  2. 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

  3. Restoration and management for plant diversity enhances the rate of belowground ecosystem recovery.

    Science.gov (United States)

    Klopf, Ryan P; Baer, Sara G; Bach, Elizabeth M; Six, Johan

    2017-03-01

    The positive relationship between plant diversity and ecosystem functioning has been criticized for its applicability at large scales and in less controlled environments that are relevant to land management. To inform this gap between ecological theory and application, we compared recovery rates of belowground properties using two chronosequences consisting of continuously cultivated and independently restored fields with contrasting diversity management strategies: grasslands restored with high plant richness and managed for diversity with frequent burning (n = 20) and grasslands restored with fewer species that were infrequently burned (n = 15). Restoration and management for plant diversity resulted in 250% higher plant richness. Greater recovery of roots and more predictable recovery of the active microbial biomass across the high diversity management strategy chronosequence corresponded with faster recovery of soil structure. The high diversity grasslands also had greater nutrient conservation indicated by lower available inorganic nitrogen. Thus, mesic grasslands restored with more species and managed for high plant diversity with frequent burning enhances the rate of belowground ecosystem recovery from long-term disturbance at a scale relevant to conservation practices on the landscape.

  4. Aquatic Plants and their Control.

    Science.gov (United States)

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  5. 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

  6. 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.

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

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    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.

  8. 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.

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

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    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.

  10. Climate change and plant disease management.

    Science.gov (United States)

    Coakley, S M; Scherm, H; Chakraborty, S

    1999-09-01

    ▪ Abstract  Research on impacts of climate change on plant diseases has been limited, with most work concentrating on the effects of a single atmospheric constituent or meteorological variable on the host, pathogen, or the interaction of the two under controlled conditions. Results indicate that climate change could alter stages and rates of development of the pathogen, modify host resistance, and result in changes in the physiology of host-pathogen interactions. The most likely consequences are shifts in the geographical distribution of host and pathogen and altered crop losses, caused in part by changes in the efficacy of control strategies. Recent developments in experimental and modeling techniques offer considerable promise for developing an improved capability for climate change impact assessment and mitigation. Compared with major technological, environmental, and socioeconomic changes affecting agricultural production during the next century, climate change may be less important; it will, however, add another layer of complexity and uncertainty onto a system that is already exceedingly difficult to manage on a sustainable basis. Intensified research on climate change-related issues could result in improved understanding and management of plant diseases in the face of current and future climate extremes.

  11. 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.

  12. 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

  13. Managing nutrient for both food security and environmental sustainability in China: an experiment for the world

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    Fusuo ZHANG, Zhenling CUI, Weifeng ZHANG

    2014-02-01

    Full Text Available The challenges of how to simultaneously ensure global food security, improve nitrogen use efficiency (NUE and protect the environment have received increasing attention. However, the dominant agricultural paradigm still considers high yield and reducing environmental impacts to be in conflict with one another. Here we examine a Three-Step-Strategy of past 20 years to produce more with less in China, showing that tremendous progress has been made to reduce N fertilizer input without sacrificing crop yield. The first step is to use technology for in-season root-zone nutrient management to significantly increase NUE. The second is to use technology for integrated nutrient management to increase both yield and NUE by 15%—20%. The third step is to use technology for integrated soil-crop system management to increase yield and NUE by 30%—50% simultaneously. These advances can thus be considered an effective agricultural paradigm to ensure food security, while increasing NUE and improving environmental quality.

  14. Crop yield and nutrient balance influenced by shoot biomass management and pig slurry application

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    Carla M. Pandolfo

    2016-04-01

    Full Text Available ABSTRACT Crop systems that export large amounts of nutrients from the farm may require higher doses of animal manure than those needed for grain production. This study aimed to evaluate the yield of crops and to determine the simplified nutrient balance in three management systems of shoot biomass of crops (cover-grain, cover-silage and hay-silage associated with five fertilization treatments (control, soluble fertilizer and three doses of pig slurry. The experimental design was a split plot, arranged in randomized blocks with four replicates. The management systems of shoot biomass did not affect the yield of the winter pasture, but there was an increase in yield with the application of pig slurry. The summer crops responded differently to fertilization, depending on the purpose for which they were grown, whether for grain or silage. In the three management systems of shoot biomass, there was an excess of Zn and Cu from the application of 25 m3 ha-1; N from 50 m3ha-1; and P, K and Ca + Mg at the dose of 100 m3ha-1.

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

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    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.

  16. The role of precision agriculture for improved nutrient management on farms.

    Science.gov (United States)

    Hedley, Carolyn

    2015-01-01

    Precision agriculture uses proximal and remote sensor surveys to delineate and monitor within-field variations in soil and crop attributes, guiding variable rate control of inputs, so that in-season management can be responsive, e.g. matching strategic nitrogen fertiliser application to site-specific field conditions. It has the potential to improve production and nutrient use efficiency, ensuring that nutrients do not leach from or accumulate in excessive concentrations in parts of the field, which creates environmental problems. The discipline emerged in the 1980s with the advent of affordable geographic positioning systems (GPS), and has further developed with access to an array of affordable soil and crop sensors, improved computer power and software, and equipment with precision application control, e.g. variable rate fertiliser and irrigation systems. Precision agriculture focusses on improving nutrient use efficiency at the appropriate scale requiring (1) appropriate decision support systems (e.g. digital prescription maps), and (2) equipment capable of varying application at these different scales, e.g. the footprint of a one-irrigation sprinkler or a fertiliser top-dressing aircraft. This article reviews the rapid development of this discipline, and uses New Zealand as a case study example, as it is a country where agriculture drives economic growth. Here, the high yield potentials on often young, variable soils provide opportunities for effective financial return from investment in these new technologies.

  17. Nutrient scavenging and energy management: acclimation responses in nitrogen and sulfur deprived Chlamydomonas.

    Science.gov (United States)

    Saroussi, Shai; Sanz-Luque, Emanuel; Kim, Rick G; Grossman, Arthur R

    2017-10-01

    Photosynthetic organisms have evolved to modulate their metabolism to accommodate the highly dynamic light and nutrient conditions in nature. In this review we discuss ways in which the green alga Chlamydomonas reinhardtii acclimates to nitrogen and sulfur deprivation, conditions that would limit the anabolic use of excitation energy because of a markedly reduced capacity for cell growth and division. Major aspects of this acclimation process are stringently regulated and involve scavenging the limited nutrient from internal and external sources, and the redirection of fixed carbon toward energy storage (e.g. starch, oil). However, photosynthetic organisms have also evolved mechanisms to dissipate excess absorbed light energy, and to eliminate potentially dangerous energetic electrons through the reduction of O2 and H(+) to H2O; this reduction can occur both through photosynthetic electron transport (e.g. Mehler reaction, chlororespiration) and mitochondrial respiration. Furthermore, algal cells likely exploit other energy management pathways that are currently not linked to nutrient limitation responses or that remain to be identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. 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.

  19. 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

  20. Model-based analysis of nutrient retention and management for a lowland river

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    D. Kneis

    2005-11-01

    Full Text Available In the context of the European Water Framework Directive options for improving the water quality of the lowland river Havel (Germany were assessed. The lower section of this river is actually a polytrophic river-lake system suffering from high external nutrient loading and exhibiting significant in-river turnover. In order to gain a better understanding of present conditions and to allow integrated scenarios of nutrient management to be evaluated the catchment models SWIM and ArcEGMO-Urban were coupled with a simple, newly developed nutrient TRAnsport Model (TraM. Using the TraM model, the retention of nitrogen and phosphorus in a 55 km reach of the Lower Havel River was quantified and its temporal variation was analyzed. It was examined that about 30% of the external nitrogen input to the Lower Havel is retained within the surveyed river section. A comparison of simulation results generated with and without consideration of phosphorus retention/release revealed that summer TP concentrations are currently increased by 100–200% due to internal loading. Net phosphorus release rates of about 20 mg P m−2 d-1 in late summer were estimated for the Havel lakes. Scenario simulations with lowered external nutrient inputs revealed that persistent phosphorus limitation of primary production cannot be established within the next decade. It was shown that a further reduction in nitrogen concentrations requires emissions to be reduced in all inflows. Though the TraM model needs further extension it proved to be appropriate for conducting integrated catchment and river modeling.

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

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    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.

  2. 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.

  3. 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

  4. Effect of elevated [CO2] and nutrient management on wet and dry season rice production in subtropical India

    Institute of Scientific and Technical Information of China (English)

    Sushree Sagarika Satapathy; Dillip Kumar Swain; Surendranath Pasupalak; Pratap Bhanu Singh Bhadoria

    2015-01-01

    The present experiment was conducted to evaluate the effect of elevated [CO2] with varying nutrient management on rice–rice production system. The experiment was conducted in the open field and inside open-top chambers (OTCs) of ambient [CO2] (≈390μmol L−1) and elevated [CO2] environment (25%above ambient) during wet and dry seasons in 2011–2013 at Kharagpur, India. The nutrient management included recommended doses of N, P, and K as chemical fertilizer (CF), integration of chemical and organic sources, and application of increased (25%higher) doses of CF. The higher [CO2] level in the OTC increased aboveground biomass but marginally decreased filled grains per panicle and grain yield of rice, compared to the ambient environment. However, crop root biomass was increased significantly under elevated [CO2]. With respect to nutrient management, increasing the dose of CF increased grain yield significantly in both seasons. At the recommended dose of nutrients, integrated nutrient management was comparable to CF in the wet season, but significantly inferior in the dry season, in its effect on growth and yield of rice. The [CO2] elevation in OTC led to a marginal increase in organic C and available P content of soil, but a decrease in available N content. It was concluded that increased doses of nutrients via integration of chemical and organic sources in the wet season and chemical sources alone in the dry season will minimize the adverse effect of future climate on rice production in subtropical India.

  5. The role of high frequency monitoring in understanding nutrient pollution processes to address catchment management issues

    Science.gov (United States)

    Quinn, Paul; Jonczyk, Jennine; Owen, Gareth; Barber, Nick; Adams, Russell; ODonnell, Greg; EdenDTC Team

    2015-04-01

    The process insights afforded to catchment scientists through the availability of high frequency time series of hydrological and nutrient pollution datasets are invaluable. However, the observations reveal both good and bad news for the WFD. Data for flow, N, P and sediment (taken at 30 min intervals) from the River Eden Demonstration Test Catchment and several other detailed UK studies, will be used to discuss nutrient fluxes in catchments between 1km2 and 10km2. Monitoring of the seasonal groundwater status and the forensic analysis of numerous storm events have identified dominant flow pathways and nutrient losses. Nonetheless, many of the management questions demanded by the WFD will not be resolved by collecting these datasets alone. Long term trends are unlikely to be determined from these data and even if trends are found they are unlikely to be accurately apportioned to the activities that have caused them. The impacts of where and when an action takes place will not be detected at the catchment scale and the cost effectiveness of any mitigation method is unlikely to be quantifiable. Even in small well instrumented catchments the natural variability in rainfall, antecedent patterns and the variability in farming practices will mask any identifiable catchment scale signal. This does not mean the cost of the data acquisition has been wasted, it just means that the knowledge and expertise gained from these data should be used in new novel ways. It will always be difficult to quantify the actual losses occurring at the farm or field scale, but the positive benefits of any mitigation may still be approximated. The evidence for the rate of nutrient removal from a local sediment trap, wetland and a pond can be shown with high resolution datasets. However, any quantifiable results are still highly localised and the transfer and upscaling of any findings must be done with care. Modelling these datasets is also possible and the nature of models have evolved in the

  6. EFFECT OF INTEGRATED NUTRIENT MANAGEMENT ON VEGETATIVE GROWTH AND YIELD OF TRANSPLANTED HYBRID RICE (ORYZA SATIVA L. CROP

    Directory of Open Access Journals (Sweden)

    RAYEES A. SHAH* SANDEEP KUMAR

    2014-09-01

    Full Text Available The integrated use of organic and inorganic sources of plant nutrients can help in sustainable and environmentally sound nutrient management of soils that are low in organic matter. A study was conducted  during 2009- 10 & 2010-11, on sandy loam soils, low in organic carbon, medium in available phosphorus and potash with pH of 7.5 at Agricultural Research Farm of C.C.R.(P.G. College, Muzaffarnagar U.P. India, to investigate the comparative use of  integrated nutrient management on vegetative growth and yield of hybrid rice. The experiment was laid out with fifteen treatments in a RBD. The treatments were; Control (T1, NPK 100% RDF (T2, NPK 75% RDF (T3, NPK 50% RDF + FYM @ 10 tons  ha-1 (T4, NPK 50% RDF + FYM @15 tons ha-1 (T5, NPK 50% RDF + wheat cut straw @10 tons ha-1 (T6, NPK 50% RDF + wheat cut straw @15 tons ha-1 (T7, NPK 50% RDF + Neem cake @ 2.5 tones ha-1 (T8, NPK 50% RDF + Neem cake @ 5 tones ha-1 (T9, NPK 50% RDF + Vermicompost @ 2.5 tons ha-1 (T10, NPK 50% RDF + Vermicompost @ 2.5 tons ha-1 +Azotobacter (T11, NPK 50% RDF + Vermicompost @ 2.5 tones ha-1 +PSB @ 5Kg ha-1 (T12, NPK 50% RDF + Vermicompost @ 2.5 tones ha-1 + Azospirillum (T13, NPK 50% RDF  + Azotobacter + Azospirillum + PSB @ 5 Kg ha-1(T14, and NPK 50% RDF + Neem cake @ 2.5 tones ha-1 +FYM @5 tons  ha-1 + Azotobacter+PSB @ 5Kg ha-1 (T15. The maximum grain yield (63 and 67 q per hectare during 2009 and 2010, respectively was obtained with the integration of NPK 50% RDF + Neem cake @2.5 tonnes ha-1 + FYM @5 tonnes ha-1+Azotobacter+PSB @ 5kg ha-1.

  7. Managing soil nutrients with compost in organic farms of East Georgia

    Science.gov (United States)

    Ghambashidze, Giorgi

    2013-04-01

    Soil Fertility management in organic farming relies on a long-term integrated approach rather than the more short-term very targeted solutions common in conventional agriculture. Increasing soil organic matter content through the addition of organic amendments has proven to be a valuable practice for maintaining or restoring soil quality. Organic agriculture relies greatly on building soil organic matter with compost typically replacing inorganic fertilizers and animal manure as the fertility source of choice. In Georgia, more and more attention is paid to the development of organic farming, occupying less than 1% of total agricultural land of the country. Due to increased interest towards organic production the question about soil amendments is arising with special focus on organic fertilizers as basic nutrient supply sources under organic management practice. In the frame of current research two different types of compost was prepared and their nutritional value was studied. The one was prepared from organic fraction municipal solid waste and another one using fruit processing residues. In addition to main nutritional properties both composts were tested on heavy metals content, as one of the main quality parameter. The results have shown that concentration of main nutrient is higher in municipal solid waste compost, but it contains also more heavy metals, which is not allowed in organic farming system. Fruit processing residue compost also has lower pH value and is lower in total salt content being is more acceptable for soil in lowlands of East Georgia, mainly characterised by alkaline reaction. .

  8. Genetics of non-alcoholic fatty liver disease: From susceptibility and nutrient interactions to management

    Institute of Scientific and Technical Information of China (English)

    Vishnubhotla; Venkata; Ravi; Kanth; Mitnala; Sasikala; Mithun; Sharma; Padaki; Nagaraja; Rao; Duvvuru; Nageshwar; Reddy

    2016-01-01

    Genetics plays an important role in determining the susceptibility of an individual to develop a disease. Complex, multi factorial diseases of modern day(diabetes, cardiovascular disease, hypertension and obesity) are a result of disparity between the type of food consumed and genes, suggesting that food which does not match the host genes is probably one of the major reasons for developing life style diseases. Non-alcoholic fatty liver is becoming a global epidemic leading to substantial morbidity. While various genotyping approaches such as whole exome sequencing using next generation sequencers and genome wide association studies have identified susceptibility loci for non-alcoholic fatty liver disease(NAFLD) including variants in patatin-like phospholipase domain containing 3 and transmembrane 6 superfamily member 2 genes apart from others; nutrient based studies emphasized on a combination of vitamin D, E and omega-3 fatty acids to manage fatty liver disease. However majority of the studies were conducted independent of each other and very few studies explored the interactions between the genetic susceptibility and nutrient interactions. Identifying such interactions will aid in optimizing the nutrition tailor made to an individual’s genetic makeup, thereby aiding in delaying the onset of the disease and its progression. The present topic focuses on studies that identified the genetic susceptibility for NAFLD, nutritional recommendations, and their interactions for better management of NAFLD.

  9. Sensitive Plants - Center for Natural Lands Management [ds458

    Data.gov (United States)

    California Department of Resources — This dataset represents sensitive plant data collected on Center for Natural Lands Management (CNLM) dedicated nature preserves in San Diego County, California. Data...

  10. 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.

  11. Effects of cattle and manure management on the nutrient economy of mixed farms in East Africa: A scenario study

    NARCIS (Netherlands)

    Snijders, P.J.M.; Meer, van der H.G.; Onduru, D.D.; Ebanyat, P.; Ergano, K.; Zake, J.Y.K.; Wouters, A.P.; Gachimbi, L.N.; Keulen, van H.

    2013-01-01

    This paper explores effects of animal and manure management in a dairy unit on the nutrient economy of crop-livestock farms in East Africa. For this purpose, 8 cattle management scenarios have been developed based on farming systems in Mbeere, Kenya (extensive), Wakiso, Uganda (semi-intensive) and K

  12. Bioextraction potential of seaweed in Denmark - An instrument for circular nutrient management.

    Science.gov (United States)

    Seghetta, Michele; Tørring, Ditte; Bruhn, Annette; Thomsen, Marianne

    2016-09-01

    The aim of the study is to assess the efficacy of seaweed for circular nutrient management to reduce eutrophication levels in the aquatic environment. We performed a comparative Life Cycle Assessment (LCA) of two reference waste management systems treating seaweed as biowaste, i.e. landfill disposal and combustion, and an alternative scenario using the seaweed Saccharina latissima as a resource for biobased fertilizer production. Life Cycle Impact Assessment (LCIA) methods were improved by using a cradle-to-cradle approach, quantifying fate factors for nitrogen and phosphorus loss from fertilized agriculture to the aquatic environment. We also differentiated between nitrogen- and phosphorus-limited marine water to improve the traditional freshwater impact category, making this indicator suitable for decision support in relation to coastal water management schemes. Offshore cultivation of Saccharina latissima with an average productivity of 150Mg/km(2) in Danish waters in 2014 was applied to a cultivation scenario of 208km(2). The bioresource scenario performs better than conventional biowaste management systems, delivering a net reduction in aquatic eutrophication levels of 32.29kgNeq. and 16.58kgPO4(3-)eq. per Mg (dry weight) of seaweed, quantified by the ReCiPe and CML impact assessment methods, respectively. Seaweed cultivation, harvest and reuse of excess nutrients from the aquatic environment is a promising approach for sustainable resource cycling in a future regenerative economy that exploits manmade emissions as a resource for closed loop biobased production while significantly reducing eutrophication levels in 3 out of 7 Danish river basin districts. We obtained at least 10% bioextraction of phosphorus manmade emissions (10%, 89% and >100%) and contributed significantly to local nitrogen reduction goals according to the Water Framework Directive (23%, 78% and >100% of the target).

  13. Response of intercrops and nutrient management on the performance of tobacco based intercropping system and assessment of system sustainability

    OpenAIRE

    Singh, Anil Kumar; Singh, KA; Bharati, RC; Chandra, Naresh

    2013-01-01

    Intercropping of tobacco with garlic produced the highest total (2292 kg/ha) and first grade (1256 kg/ha) cured leaves of tobacco. In the recommended dose of respective intercrops 75% produced total and first grade cured tobacco leaves compared to 100 per cent of the recommended dose. Tobacco quality was also influenced with nutrient management. Puckering and maturity scores did not impaired up to 50 per cent application of nutrients to intercrops. Among the intercrops garlic gave the highest...

  14. Maintaining adequate nutrient supply - Principles, decision-support tools, and best management practices [Chapter 6

    Science.gov (United States)

    Robert B. Harrison; Douglas A. Maguire; Deborah Page-Dumroese

    2011-01-01

    Maintaining adequate nutrient supply to maintain or enhance tree vigor and forest growth requires conservation of topsoil and soil organic matter. Sometimes nutrient amendments are also required to supplement inherent nutrient-pool limitations or replenish nutrients removed in harvested material. The goal is to maintain the productive potential of the soil and, when...

  15. Is fire exclusion in mountain big sagebrush communities prudent? Soil nutrient, plant diversity, and arthropod response to burning

    Science.gov (United States)

    Fire has largely been excluded from many mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana (Rydb.) Beetle) communities. Land and wildlife managers are especially reluctant to reintroduce fire in mountain big sagebrush plant communities, especially those communities without significan...

  16. 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

  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

  18. 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

  19. 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

  20. Framatome ANP worldwide experience in ageing and plant life management

    Energy Technology Data Exchange (ETDEWEB)

    Daeuwel, W.; Kastner, B.; Nopper, H. [Framatome ANP (Germany)

    2004-07-01

    The deregulation of the power generation industry has resulted in increased competitive pressure and is forcing operators to improve plant operating economy while maintaining high levels of plant safety. A key factor to meet this challenge is to apply a comprehensive plant life management (PLIM) approach which addresses all relevant ageing and degradation mechanisms regarding the safety concept, plant components and documentation, plant personnel, consumables, operations management system and administrative controls. For this reason, Framatome ANP has developed an integrated PLIM concept focussing on the safety concept, plant components and documentation. Representative examples for plant wide analyses are described in the following. The results of the analyses support the plant owner for taking the strategic decisions, involved in plant life extension (PLEX). (orig.)

  1. Clipping and irrigation enhance grass biomass and nutrients: Implications for rangeland management

    Science.gov (United States)

    Tuffa, Samuel; Hoag, Dana; Treydte, Anna C.

    2017-05-01

    Increasing frequency of drought and high herbivore pressure significantly affect individual grass functions in semiarid regions. Reseeding of degraded rangelands by native grass species has been recommended as a tool for restoration semiarid rangelands. However, how grass species used for reseeding respond to stressors has not been fully explored. We examined biomass allocation and nutrient contents of Cenchrus ciliaris and Chloris gayana in the semiarid Borana rangelands, Ethiopia. We tested clipped mature tufts of the same species for biomass allocation and nutritive values. Further, shifts in rainfall and herbivory were simulated by three irrigation and four clipping treatments, respectively, for newly established grasses in pot and field plot experiments. Aboveground biomass (AGB) significantly declined by up to 75% under increased clipping in mature tufts. In contrast, clipping significantly stimulated up to 152% higher AGB of newly established grasses. Lower irrigation reduced the AGB by 24 and 42% in C. ciliaris and in C. gayana, respectively. Clipping, further, significantly enhanced grass nutrients in grass tufts by up to 82 and 105% in C. ciliaris and C. gayana, respectively. Hence, management should focus on balancing this trade-off in mature grasses for nutritious rangeland production by clipping and storing for later supplemental feeding when grass nutrients drop. Further, young pastures should be moderately clipped/grazed for better establishment and biomass allocation. Additionally, our experiments established the first interactive effect of clipping and irrigation frequencies on the biomass allocation of native grasses in the semiarid Borana rangelands, Ethiopia. Knowledge of these interacting factors is deemed essential for policy makers to enhance productivity of degraded rangelands such as the Borana rangelands.

  2. 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...

  3. Nutrient sources in a Mediterranean catchment and their improvement for water quality management

    Science.gov (United States)

    Candela, Angela; Viviani, Gaspare

    2010-05-01

    Changes in land-use or management strategies may affect water outflow, sediment and nutrients loads. Thus, there is an increasing demand for quantitative information at the catchment scale that would help decision makers or planners to take appropriate decisions. The characterisation of water status, the description of pollution sources impact, the establishment of monitoring programs and the implementation of river basin management plans require an analysis of the current basin status and estimates of the relative significance of the different sources of pollution. Particularly, in this study the Soil and Water Assessment Tool (SWAT2000) model was considered since it is an integrated hydrological model that simulates both the qualitative as well as quantitative terms of hydrological balances. It is a spatially distributed hydrological model that operates on a daily time step at catchment scale developed by the Agricultural Research Service at the U.S. Department of Agriculture. Its purpose is to simulate water sediment and chemical yields on large river basins and possible impacts of land use, climate changes and watershed management. Integrated hydrological models are, nowadays, needed to support the implementation of integrated water management plans and to comply with the current requirements of the European Water Directive. Actually, they can help in evaluating current water resources, identify pollution sources, evaluate alternative management policies. More specifically, the analysis has been applied to the Oreto catchment (77 Km2), an agricultural and urbanised catchment located in Sicily (Italy). Residential, commercial, farm and industrial settlements cover almost the entire area. The climate is Mediterranean with hot dry summer and rainy winter season. The hydrological response of this basin is dominated by long dry seasons and following wetting-up periods, during which even large inputs of rainfall may produce little or no response at the basin outlet

  4. 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).

  5. Ecological principles underpinning invasive plant management tools and strategies

    Science.gov (United States)

    The broad focus of ecologically-based invasive plant management is to identify and repair the ecological processes facilitating plant invasion. To be useful, however, EBIPM requires that our application of management tools and strategies be based on ecological principles that determine the rate and ...

  6. INTEGRATED NUTRIENT MANAGEMENT IN SUNFLOWER +APIARY FARMING SYSTEM FOR SUSTAINABLE PRODUCTIVITY

    Directory of Open Access Journals (Sweden)

    G .SUMALATHA AND T. GEETHA JEBARATHNAM

    2014-10-01

    Full Text Available ABSTRACT: Two sets of field experiments were conducted during  June-August months of 2012-2013 at Annamalai University of Cuddalore district under irrigated conditions to formulate site –specific nutrient management and to assess the yield  performance of sunflower +apiary farming system.The experiment consists of two main treatments; i.e, sunflower alone (M1 ,sunflower  with apiary (M2 and nine sub treatments i.e, control (S1, 100%RDF (S2, 100%RDF + Azospirillum (S3,100% RDF+phosphobacteria (S4,100%RDF+vermicompost (S5, 100%RDF+ Azospirillum+ phosphobacteria (S6, 100% RDF + Vermicompost +Azospirillum (S7, 100%RDF+ vermicompost+phosphobacteria (S8,100%RDF + Vermicompost + Azospirillum+phosphobacteria(S9 and it was laid out in split plot design with three replications .Highest values for seed yield and NPK uptake were observed for the combined application of all three nutrient sources in the plots of the experiment where beehive was installed. Perhaps to ensure better outcome. The apiary should be provided with better feeding for a longer period of time, beside  the natural feeding resources .feed consists of 500ml sugar syrup two times a week. Infact the bee foraging activites, improved seed yield, apart from the income through honey production, thus sustaining the crop + apiary system.

  7. Large Wood Increases Floodplain Connectivity: Implications for Sediment and Nutrient Management

    Science.gov (United States)

    Jones, C. N.; Keys, T.; Govenor, H.; Hession, W. C.; Scott, D.; Hester, E. T.; Krometis, L. A. H.

    2016-12-01

    Large wood (LW) in streams provides ecosystem services ranging from encouraging geomorphic stability, providing critical habitat, and enhancing downstream water quality. The latter occurs because LW creates zones of transient storage along the river corridor, promoting depositional processes and biogeochemical processing of reactive solutes. While there is a large body of work that examines the role of LW during baseflow, less is known about effects during overbank flow events. We created two experimental floods - one without LW and one with - in a headwater Appalachian stream to examine the role of LW on river-floodplain connectivity. Flow was measured at the upstream and downstream boundaries of the study reach while suspended sediment transport, bed deposition, and floodplain inundation were measured at four cross sections. Rare earth element labeled sediment, injected into the stream with the flood pulse, was used to trace the fate and transport of fine particles. A hydraulic model was created to characterize river-floodplain connectivity and nutrient cycling. Initial results suggest that large wood dramatically increases river-floodplain connectivity and sediment deposition in small streams - leading to increases in transient storage. Implications for nutrient cycling, sediment flushing, and the potential use of LW as a best management practice in stream and river restoration are discussed.

  8. 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.

  9. Development of cost effective nutrient management strategies for a watershed with the DSS FyrisCOST

    Science.gov (United States)

    Collentine, D.; Johnsson, H.; Larsson, P.; Markensten, H.; Widén Nilsson, E.

    2012-12-01

    This paper describes an application of the FyrisCOST model to calculate the cost efficiency of alternative scenarios for nitrogen management in a small agricultural catchment in Southern Sweden. The scenarios include the spatial distribution by sub-catchment of a set of nitrogen abatement measures that have been identified as eligible for financial support under the Swedish Rural Development Program (wetlands, catch crops, spring plowing and a combination of these) with alternative crop distributions. The model FyrisCOST is a catchment scale DSS that has been developed for the evaluation of alternative nutrient mitigation strategies. This model is able to evaluate a range of mitigation approaches for phosphorous and nitrogen from several sources (point and diffuse). This allows cost efficiency to be estimated for a catchment based on a combination of measures. The model is currently being used to develop a data base for the Swedish Water Authorities on the cost efficiency of buffer zones for all small catchments in Sweden. Hydrological flows in the FyrisCOST model are built on the dynamic model FyrisNP and nutrient losses are derived from simulations from the Nutrient Leaching Coefficient Calculation System (NLeCCS) which includes the ICECREAMDB model for estimating phosphorus losses and the SOILNDB model for soil nitrogen leaching. FyrisCOST calculates nitrogen concentrations in effluent water for each sub-catchment. The concentration of nitrogen is dependent on the current land use and geographical conditions. In order to evaluate agricultural scenarios in FyrisCOST a method for calculating N leaching from agricultural land was constructed. The calculation includes crop rotations and tillage systems and differentiates between annual and perennial crops. The model is able to take into account the probability that a primary crop is followed by a specific crop/tillage system and the effect on nutrient losses estimated using a specially developed leaching

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. Assessment of management-dependent nutrient losses in tropical industrial tree plantations.

    Science.gov (United States)

    Mackensen, Jens; Klinge, Rudolf; Ruhiyat, Daddy; Fölster, Horst

    2003-03-01

    Industrial tree plantations in the tropics usually follow short rotations and intensive site management including slash and burn, and the use of heavy machinery. We attempt to quantify the implied nutrient losses (harvest export, erosion, slash and burn, leaching) in order to give plantation managers a chance to understand the significance of their planning and decisions. We used the scarce globally available information and a case study plantation in East Kalimantan, Indonesia (Acacia mangium and Eucalyptus deglupta). Adaptation involves problems and is discussed in some detail. Results are approximate only. Assuming a harvest volume of 200 m3 ha(-1), we assessed a loss of 427-680 kg ha(-1) N, 12-13 kg ha(-1) P, 178-252 kg ha(-1) Ca, 276-370 kg ha(-1) K, and 45-57 kg ha(-1) Mg per rotation. Of this overall loss, stand harvest accounted for 18-29% (N), 21-30% (P), 56-26% (K), 48-64% (Ca) and 22-37% (Mg). This means that the cumulative loss by erosion, slash and burn, and leaching exceeds that of the harvest. These losses can be influenced by management.

  15. 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

  16. 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...

  17. 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...

  18. 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

  19. 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...

  20. 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

  1. Economic benefits of combining soil and water conservation measures with nutrient management in semiarid Burkina Faso

    NARCIS (Netherlands)

    Zougmoré, R.; Mando, A.; Stroosnijder, L.; Ouédraogo, E.

    2004-01-01

    Nutrient limitation is the main cause of per capita decline in crop production in the Sahel, where water shortage also limits an efficient use of available nutrients. Combining soil and water conservation measures with locally available nutrient inputs may optimize crop production and economic benef

  2. [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.

  3. 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...

  4. Crop management as a driving force of plant growth promoting rhizobacteria physiology.

    Science.gov (United States)

    Melo, Juliana; Carolino, Manuela; Carvalho, Luís; Correia, Patrícia; Tenreiro, Rogério; Chaves, Sandra; Meleiro, Ana I; de Souza, Sávio B; Dias, Teresa; Cruz, Cristina; Ramos, Alessandro C

    2016-01-01

    Crop management systems influence plant productivity and nutrient use efficiency, as well as plant growth-promoting rhizobacteria (PGPR), which are known to influence the growth of plants via phytohormone production, phosphate solubilization, nitrogen (N) fixation and antimicrobial activity. The objective of this study was to compare the influence of two crop management system on microbial PGPR features. PGPR isolated from the rhizospheres of Carica papaya L. grown under two distinct management systems (conventional and organic) were identified and characterized. The 12 strains most efficient in solubilizing inorganic phosphate belonged to the genera Burkholderia, Klebsiella, and Leclercia. N fixation was observed in the strains B. vietnamiensis from the conventional farming system and B. vietnamiensis, B. cepacia and Leclercia sp. from the organic farming system. The B. vietnamiensis, B. cepacia, Klebsiella sp. and Klebsiella sp. isolates showed antifungal activity, while Leclercia sp. did not. The strains B. vietnamiensis and Enterobcter sp. (isolated from the conventional farming system) and Klebsiella sp. (isolated from the organic farming system) were efficient at solubilizing phosphate, producing phytohormones and siderophores, and inhibiting the mycelial growth of various phytopathogenic fungi (Botrytis cinerea, Pestalotia sp., Alternaria sp., Phoma sp., Fusarium culmorum, Geotrichum candidum). Physiological differences between the isolates from the two crop management regimes were distinguishable after 10 years of distinct management.

  5. Effect of elevated [CO2] and nutrient management on wet and dry season rice production in subtropical India

    Institute of Scientific and Technical Information of China (English)

    Sushree Sagarika Satapathy; Dillip Kumar Swain; Surendranath Pasupalak; Pratap Bhanu Singh Bhadoria

    2015-01-01

    The present experiment was conducted to evaluate the effect of elevated [CO2] with varying nutrient management on rice–rice production system. The experiment was conducted in the open field and inside open-top chambers(OTCs) of ambient [CO2](≈ 390 μmol L-1) and elevated [CO2] environment(25% above ambient) during wet and dry seasons in 2011–2013at Kharagpur, India. The nutrient management included recommended doses of N, P, and K as chemical fertilizer(CF), integration of chemical and organic sources, and application of increased(25% higher) doses of CF. The higher [CO2] level in the OTC increased aboveground biomass but marginally decreased filled grains per panicle and grain yield of rice, compared to the ambient environment. However, crop root biomass was increased significantly under elevated [CO2]. With respect to nutrient management, increasing the dose of CF increased grain yield significantly in both seasons. At the recommended dose of nutrients, integrated nutrient management was comparable to CF in the wet season, but significantly inferior in the dry season, in its effect on growth and yield of rice. The [CO2] elevation in OTC led to a marginal increase in organic C and available P content of soil, but a decrease in available N content. It was concluded that increased doses of nutrients via integration of chemical and organic sources in the wet season and chemical sources alone in the dry season will minimize the adverse effect of future climate on rice production in subtropical India.

  6. 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.

  7. Master plan: Guntersville Reservoir Aquatic Plant Management. Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    In 1989, Congress provided funding to start a five-year comprehensive project to manage aquatic plants in Guntersville Reservoir, to be jointly implemented by the US Army Corps of Engineers (Corps) and Tennessee Valley Authority (TVA). TVA serves as the overall project coordinator and is the lead agency for this project. Known as the Joint Agency Guntersville Project (JAGP), the project will test and demonstrate innovative management technologies, and incorporate the most effective technologies into a comprehensive aquatic plant management plan for Guntersville Reservoir. The JAGP is intended to serve as a National Demonstration Project for aquatic plant management. As part of this JAGP, the Master Plan for Aquatic Plant Management for the Guntersville Reservoir Project, Alabama-Tennessee is authorized by Corps Contract Number DACW62-90-C-0067.

  8. Nutrient depletion from rhizosphere solution by maize grown in soil with long-term compost amendment

    Science.gov (United States)

    Improved understanding of rhizosphere chemistry will enhance our ability to model nutrient dynamics and on a broader scale, to develop effective management strategies for applied plant nutrients. With a controlled-climate study, we evaluated in situ changes in macro-nutrient concentrations in the rh...

  9. 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.

  10. Dryland maize yields and water use efficiency in response to tillage/crop stubble and nutrient management practices in China

    NARCIS (Netherlands)

    Wang, X.B.; Dai, K.; Zhang, D.; Zhang, X.; Wang, Y.; Zhao, Q.; Cai, D.X.; Hoogmoed, W.B.; Oenema, O.

    2011-01-01

    Rainfed crop production in northern China is constrained by low and variable rainfall. This study explored the effects of tillage/crop residue and nutrient management practices on maize (Zea mays L.) yield, water use efficiency (WUE), and N agronomic use efficiency (NAE) at Shouyang Dryland Farming

  11. Dryland maize yields and water use efficiency in response to tillage and nutrient management practices in China

    NARCIS (Netherlands)

    Wang, X.B.; Dai, K.; Zhao, Q.; Cai, D.X.; Hoogmoed, W.B.; Oenema, O.

    2009-01-01

    Rainfed crop production in northern China is constrained by low and variable rainfall. This study explored the effects of tillage and nutrient management practices on maize (Zea mays L.) yield and water use efficiency (WUE), at Shouyang Dryland Farming Experimental Station in northern China during 2

  12. 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.

  13. 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.

  14. Soil redistribution and nutrient delivery in a Mediterranean rain-fed agro-ecosystem with different crops and management: environmental and economic aspects

    Science.gov (United States)

    López-Vicente, Manuel; Álvarez, Sara

    2017-04-01

    Mediterranean agro-ecosystems are characterised by fragmented fields and patched vegetation. This shape governs the spatial patterns of water, soil and nutrient redistribution. Rainfall parameters, human infrastructures, crop management, support practices, and land use changes (set aside crops, land abandonment) control the magnitude of these processes. Under rain-fed water supply conditions, runoff generation and soil water content are two important factors in determining crop yield. Soil erosion and nutrient delivery are two of the factors which limit crop yield and thus, the gross earning of the landowner. In hilly landscapes, farmers usually supply extra soil to fill in the ephemeral gullies, and nutrient replenishment with fertilizers is a common practice. The aim of this study is to evaluate the environmental (runoff yield, soil erosion and nutrient delivery) and economic (replenishment of soil and nutrient losses with new soil and fertilizers) consequences of different conventional and conservative practices (fallow/crop rotation, cover crops, land abandonment, buffer strips) in a Mediterranean rain-fed agro-ecosystem (27 ha) with vineyards, cereal crops, cultivated and abandoned olive orchards, several trails and patches of natural vegetation. The five winter cereal fields (wheat and barley) follow fallow/crop rotation. The four vineyards are devoted to the Garnacha variety: one planted in 2007 with white wine grapes, and three planted in 2008 with red wine grapes. The inter-crop strips are managed with a mixture of plant species as cover crop (CC), including: i) spontaneous vegetation, and ii) plantation of common sainfoin (Onobrychis viciifolia). The maintenance of the CC includes one mowing pass at the end of spring, between May and June. The appearance and development of ephemeral gullies and the deposition of soil at the bottom of the hillslope are two of the main concerns of the landowners. In some places, the accumulation of soil complicates grape

  15. 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.

  16. Environmental assessment of management options for nutrient flows in the food chain in China.

    Science.gov (United States)

    Ma, Lin; Wang, Fanghao; Zhang, Weifeng; Ma, Wenqi; Velthof, Gerard; Qin, Wei; Oenema, Oene; Zhang, Fusuo

    2013-07-02

    The nitrogen (N) and phosphorus (P) costs of food production have increased greatly in China during the last 30 years, leading to eutrophication of surface waters, nitrate leaching to groundwater, and greenhouse gas emissions. Here, we present the results of scenario analyses in which possible changes in food production-consumption in China for the year 2030 were explored. Changes in food chain structure, improvements in technology and management, and combinations of these on food supply and environmental quality were analyzed with the NUFER model. In the business as usual scenario, N and P fertilizer consumption in 2030 will be driven by population growth and diet changes and will both increase by 25%. N and P losses will increase by 44 and 73%, respectively, relative to the reference year 2005. Scenarios with increased imports of animal products and feed instead of domestic production, and with changes in the human diet, indicate reductions in fertilizer consumption and N and P losses relative to the business as usual scenario. Implementation of a package of integrated nutrient management measures may roughly nullify the increases in losses in the business as usual scenario and may greatly increase the efficiency of N and P throughout the whole food chain.

  17. BALTICA IV. Plant maintenance for managing life and performance

    Energy Technology Data Exchange (ETDEWEB)

    Hietanen, S.; Auerkari, P. [eds.] [VTT Manufacturing Technology, Espoo (Finland). Operational Reliability

    1998-12-31

    BALTICA IV International Conference on Plant Maintenance Managing Life and performance held on September 7-9, 1998 on board M/S Silja Symphony on its cruise between Helsinki-Stockholm and at Aavaranta in Kirkkonummi. The BALTICA IV conference provides a forum for the transfer of technology from applied research to practice. This is one of the two volumes of the proceedings of the BALTICA IV International Conference on Plant Maintenance Managing Life and Performance. The BALTICA IV conference focuses on new technology, recent experience and applications of condition and life management, and on improvements in maintenance strategies for safe and economical operation of power plants. (orig.)

  18. Crisis management with applicability on fire fighting plants

    Science.gov (United States)

    Panaitescu, M.; Panaitescu, F. V.; Voicu, I.; Dumitrescu, L. G.

    2017-08-01

    The paper presents a case study for a crisis management analysis which address to fire fighting plants. The procedures include the steps of FTA (Failure tree analysis). The purpose of the present paper is to describe this crisis management plan with tools of FTA. The crisis management procedures have applicability on anticipated and emergency situations and help to describe and planning a worst-case scenario plan. For this issue must calculate the probabilities in different situations for fire fighting plants. In the conclusions of paper is analised the block diagram with components of fire fighting plant and are presented the solutions for each possible risk situations.

  19. Aging management guideline for commercial nuclear power plants - heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

    1994-06-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  20. BALTICA IV. Plant maintenance for managing life and performance

    Energy Technology Data Exchange (ETDEWEB)

    Hietanen, S.; Auerkari, P. [eds.] [VTT Manufacturing Technology, Espoo (Finland). Operational Reliability

    1998-12-31

    BALTICA IV International Conference on Plant Maintenance Managing Life and performance held on September 7-9, 1998 on board M/S Silja Symphony on its cruise between Helsinki-Stockholm and at Aavaranta in Kirkkonummi. The BALTICA IV conference provides a forum for the transfer of technology from applied research to practice. This is one of the two volumes of the proceedings of the BALTICA IV International Conference on Plant Maintenance Managing Life and Performance. The BALTICA IV conference focuses on new technology, recent experience and applications of condition and life management, and on improvements in maintenance strategies for safe and economical operation of power plants. (orig.)

  1. 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.

  2. 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...

  3. Controlling cyanobacterial blooms by managing nutrient ratio and limitation in a large hyper-eutrophic lake: Lake Taihu, China.

    Science.gov (United States)

    Ma, Jianrong; Qin, Boqiang; Wu, Pan; Zhou, Jian; Niu, Cheng; Deng, Jianming; Niu, Hailin

    2015-01-01

    Excessive nitrogen (N) and phosphorus (P) loading of aquatic ecosystems is a leading cause of eutrophication and harmful algal blooms worldwide, and reducing nutrient levels in water has been a primary management objective. To provide a rational protection strategy and predict future trends of eutrophication in eutrophic lakes, we need to understand the relationships between nutrient ratios and nutrient limitations. We conducted a set of outdoor bioassays at the shore of Lake Taihu. It showed that N only additions induced phytoplankton growth but adding only P did not. Combined N plus P additions promoted higher phytoplankton biomass than N only additions, which suggested that both N and P were deficient for maximum phytoplankton growth in this lake (TN:TP=18.9). When nutrients are present at less than 7.75-13.95 mg/L TN and 0.41-0.74 mg/L TP, the deficiency of either N or P or both limits the growth of phytoplankton. N limitation then takes place when the TN:TP ratio is less than 21.5-24.7 (TDN:TDP was 34.2-44.3), and P limitation occurs above this. Therefore, according to this ratio, controlling N when N limitation exists and controlling P when P deficiency is present will prevent algal blooms effectively in the short term. But for the long term, a persistent dual nutrient (N and P) management strategy is necessary. Copyright © 2014. Published by Elsevier B.V.

  4. 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

  5. Effect of Integrated Water-Nutrient Management Strategies on Soil Erosion Mediated Nutrient Loss and Crop Productivity in Cabo Verde Drylands.

    Science.gov (United States)

    Baptista, Isaurinda; Ritsema, Coen; Geissen, Violette

    2015-01-01

    Soil erosion, runoff and related nutrient losses are a big risk for soil fertility in Cabo Verde drylands. In 2012, field trials were conducted in two agro-ecological zones to evaluate the effects of selected techniques of soil-water management combined with organic amendments (T1: compost/manure + soil surfactant; T2: compost/animal or green manure + pigeon-pea hedges + soil surfactant; T3: compost/animal or green manure + mulch + pigeon-pea hedges) on nitrogen (N) and phosphorus (P) losses in eroded soil and runoff and on crop yields. Three treatments and one control (traditional practice) were tested in field plots at three sites with a local maize variety and two types of beans. Runoff and eroded soil were collected after each erosive rain, quantified, and analysed for NO3-N and PO4-P concentrations. In all treatments runoff had higher concentrations of NO3-N (2.20-4.83 mg L-1) than of PO4-P (0.02-0.07 mg L-1), and the eroded soil had higher content of PO4-P (5.27-18.8 mg g-1) than of NO3-N (1.30-8.51 mg g-1). The control had significantly higher losses of both NO3-N (5.4, 4.4 and 19 kg ha-1) and PO4-P (0.2, 0.1 and 0.4 kg ha-1) than the other treatments. T3 reduced soil loss, runoff and nutrient losses to nearly a 100% while T1 and T2 reduced those losses from 43 to 88%. The losses of NO3-N and PO4-P were highly correlated with the amounts of runoff and eroded soil. Nutrient losses from the applied amendments were low (5.7% maximum), but the losses in the control could indicate long-term nutrient depletion in the soil (19 and 0.4 kg ha-1 of NO3-N and PO4-P, respectively). T1-T3 did not consistently increase crop yield or biomass in all three sites, but T1 increased both crop yield and biomass. We conclude that T3 (combining crop-residue mulch with organic amendment and runoff hedges) is the best treatment for steep slope areas but, the pigeon-pea hedges need to be managed for higher maize yield. T1 (combining organic amendment with soil surfactant) could be a

  6. Plant Profiles - Industrial Energy Management in Action

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-02-01

    This 24-page brochure profiles industrial manufacturing firms who are achieving significant energy savings in their plants. The DOE Office of Industrial Technologies six plant-of-the-year nominees are featured, and an additional 10 projects from other companies are also highlighted. Information on OIT's awards and recognition process, and information on OIT and BestPractices is also included.

  7. 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.

  8. Soil and nutrient retention in winter-flooded ricefields with implications for watershed management

    Science.gov (United States)

    Manley, S.W.; Kaminski, R.M.; Rodrigue, P.B.; Dewey, J.C.; Schoenholtz, S.H.; Gerard, P.D.; Reinecke, K.J.

    2009-01-01

    The ability of water resources to support aquatic life and human needs depends, in part, on reducing nonpoint source pollution amid contemporary agricultural practices. Winter retention of shallow water on rice and other agricultural fields is an accepted management practice for wildlife conservation; however, soil and water conservation benefits are not well documented. We evaluated the ability of four post-harvest ricefield treatment combinations (stubble-flooded, stubble-open, disked-flooded and disked-open) to abate nonpoint source exports into watersheds of the Mississippi Alluvial Valley. Total suspended solid exports were 1,121 kg ha-1 (1,000 lb ac-1) from disked-open fields where rice stubble was disked after harvest and fields were allowed to drain, compared with 35 kg ha-1 (31 lb ac-1) from stubble-flooded fields where stubble was left standing after harvest and fields captured rainfall from November 1 to March 1. Estimates of total suspended solid exports from ricefields based on Landsat imagery and USDA crop data are 0.43 and 0.40 Mg km-2 day-1 in the Big Sunflower and L'Anguille watersheds, respectively. Estimated reductions in total suspended solid exports from ricefields into the Big Sunflower and L'Anguille water-sheds range from 26% to 64% under hypothetical scenarios in which 65% to 100% of the rice production area is managed to capture winter rainfall. Winter ricefield management reduced nonpoint source export by decreasing concentrations of solids and nutrients in, and reducing runoff volume from, ricefields in the Mississippi Alluvial Valley.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Applying Functional Modeling for Accident Management of Nuclear Power Plant

    DEFF Research Database (Denmark)

    Lind, Morten; Zhang, Xinxin

    2014-01-01

    The paper investigate applications of functional modeling for accident management in complex industrial plant with special reference to nuclear power production. Main applications for information sharing among decision makers and decision support are identified. An overview of Multilevel Flow...

  14. PlantDB – a versatile database for managing plant research

    Directory of Open Access Journals (Sweden)

    Gruissem Wilhelm

    2008-01-01

    Full Text Available Abstract Background Research in plant science laboratories often involves usage of many different species, cultivars, ecotypes, mutants, alleles or transgenic lines. This creates a great challenge to keep track of the identity of experimental plants and stored samples or seeds. Results Here, we describe PlantDB – a Microsoft® Office Access database – with a user-friendly front-end for managing information relevant for experimental plants. PlantDB can hold information about plants of different species, cultivars or genetic composition. Introduction of a concise identifier system allows easy generation of pedigree trees. In addition, all information about any experimental plant – from growth conditions and dates over extracted samples such as RNA to files containing images of the plants – can be linked unequivocally. Conclusion We have been using PlantDB for several years in our laboratory and found that it greatly facilitates access to relevant information.

  15. Nutrient Cycling and Balance in Red Soil Agroecosystem and Their Management

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An experiment was conducted in a red soil derived from Quaternary red clay in the Ecological Experiment Station of Red Soil, the Chinese Academy of Sciences, located in Yingtan (28°15' 30" N, 116°55' 30" E), Jiangxi Province. The results show that the major ways of nutrient loss are leaching and nitrogen volatilization. Rationalizing crop distribution, stimulating nutrient recycling, and improving internal nutrient flow are effective measures to decrease nutrient loss and to promote nutrient utilization efficiency. The important ways of regulating nutrient cycling and balance in the agroecosystem of the red soil are to establish optimal eco-agricultural models, practice balanced fertilization and combine the cropping system with the livestock system.

  16. 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

  17. 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.

  18. 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.

  19. Public and private roles in plant health management

    NARCIS (Netherlands)

    Oude Lansink, A.G.J.M.

    2011-01-01

    World-wide, government institutions play an important role in the management of plant health. This paper develops a conceptual framework in which suppliers and demanders jointly determine the optimal level of plant health in a hypothetical market. Next this paper argues that this market falls short

  20. Adding Remote Sensing Data Products to the Nutrient Management Decision Support Toolbox

    Science.gov (United States)

    Lehrter, John; Schaeffer, Blake; Hagy, Jim; Spiering, Bruce; Blonski, Slawek; Underwood, Lauren; Ellis, Chris

    2011-01-01

    Some of the primary issues that manifest from nutrient enrichment and eutrophication (Figure 1) may be observed from satellites. For example, remotely sensed estimates of chlorophyll a (chla), total suspended solids (TSS), and light attenuation (Kd) or water clarity, which are often associated with elevated nutrient inputs, are data products collected daily and globally for coastal systems from satellites such as NASA s MODIS (Figure 2). The objective of this project is to inform water quality decision making activities using remotely sensed water quality data. In particular, we seek to inform the development of numeric nutrient criteria. In this poster we demonstrate an approach for developing nutrient criteria based on remotely sensed chla.

  1. Palmyra Atoll - Invasive Plant Management 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Remote atoll ecosystems are havens of biological diversity, but vulnerable to ecological invasion. The prosperity of the plants and animals that inhabit remote atoll...

  2. 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....

  3. Conventional and organic soil fertility management practices affect corn plant nutrition and Ostrinia nubilalis (Lepidoptera: Crambidae) larval performance.

    Science.gov (United States)

    Murrell, Ebony G; Cullen, Eileen M

    2014-10-01

    Few studies compare how different soil fertilization practices affect plant mineral content and insect performance in organic systems. This study examined: 1) The European corn borer, Ostrinia nubilalis (Hübner), larval response on corn (Zea mays L.) grown in field soils with different soil management histories; and 2) resilience of these plants to O. nubilalis herbivory. Treatments included: 1) standard organic--organically managed soil fertilized with dairy manure and 2 yr of alfalfa (Medicago sativa L.) in the rotation; 2) basic cation saturation ratio--organically managed soil fertilized with dairy manure and alfalfa nitrogen credits, plus addition of gypsum (CaSO4·2H2O) according to the soil balance hypothesis; and 3) conventional--conventionally managed soil fertilized with synthetic fertilizers. Corn plants were reared to maturity in a greenhouse, and then infested with 0-40 O. nubilalis larvae for 17 d. O. nubilalis exhibited negative competitive response to increasing larval densities. Mean development time was significantly faster for larvae consuming basic cation saturation ratio plants than those on standard organic plants, with intermediate development time on conventional plants. Neither total yield (number of kernels) nor proportion kernels damaged differed among soil fertility treatments. Soil nutrients differed significantly in S and in Ca:Mg and Ca:K ratios, but principal components analysis of plant tissue samples taken before O. nubilalis infestation showed that S, Fe, and Cu contributed most to differences in plant nutrient profiles among soil fertility treatments. Results demonstrate that different fertilization regimens can significantly affect insect performance within the context of organic systems, but the effects in this study were relatively minor compared with effects of intraspecific competition.

  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. Recovery of essential nutrients from municipal solid waste – Impact of waste management infrastructure and governance aspects

    Energy Technology Data Exchange (ETDEWEB)

    Zabaleta, Imanol, E-mail: imanol.zabaleta@eawag.ch [Eawag: Swiss Federal Institute of Aquatic Science and Technology, Department of Water and Sanitation in Developing Countries (Sandec), P.O. Box 611, 8600 Dübendorf (Switzerland); Rodic, Ljiljana, E-mail: ljiljana.rodic@gmail.com [Wageningen University, Education and Competence Studies, Wageningen (Netherlands)

    2015-10-15

    Every year 120–140 million tonnes of bio-waste are generated in Europe, most of which is landfilled, incinerated or stabilized and used as covering material in landfill operation. None of these practices enables the recovery of essential nutrients such as phosphorus (P) and nitrogen (N), which are in great demand for agricultural production. Recovery of these nutrients is a matter of international concern considering the non-renewable nature of P sources and the energy intensive production process required for the synthesis of N fertilizers. The objective of this research is to understand the relation between the municipal solid waste management (MSWM) system, both its the physical components and governance aspects, and the recovery of nutrients in Vitoria-Gasteiz (Basque Country) as a benchmark for European medium-size cities. The analysis shows that the existing physical infrastructure and facilities for bio-waste have high potential for nutrient recovery, 49% for N and 83% for P contained in bio-waste. However, governance aspects of the MSWM system such as legislation and user inclusivity play an important role and decrease the actual nutrient recovery to 3.4% and 7.4% for N and P respectively.

  6. Recovery of essential nutrients from municipal solid waste--Impact of waste management infrastructure and governance aspects.

    Science.gov (United States)

    Zabaleta, Imanol; Rodic, Ljiljana

    2015-10-01

    Every year 120-140 million tonnes of bio-waste are generated in Europe, most of which is landfilled, incinerated or stabilized and used as covering material in landfill operation. None of these practices enables the recovery of essential nutrients such as phosphorus (P) and nitrogen (N), which are in great demand for agricultural production. Recovery of these nutrients is a matter of international concern considering the non-renewable nature of P sources and the energy intensive production process required for the synthesis of N fertilizers. The objective of this research is to understand the relation between the municipal solid waste management (MSWM) system, both its the physical components and governance aspects, and the recovery of nutrients in Vitoria-Gasteiz (Basque Country) as a benchmark for European medium-size cities. The analysis shows that the existing physical infrastructure and facilities for bio-waste have high potential for nutrient recovery, 49% for N and 83% for P contained in bio-waste. However, governance aspects of the MSWM system such as legislation and user inclusivity play an important role and decrease the actual nutrient recovery to 3.4% and 7.4% for N and P respectively.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. Biomass and nutrients of Pinus massoniana plantations in southern China: simulations for different management practices.

    Science.gov (United States)

    Huixia Yang; Silong Wang; Jianwei Zhang; Bing Fan; Weidong Zhang

    2011-01-01

    We measured the dynamics of both biomass and nutrient pools on 7-, 17-, 31- and 51-year-old Pinus massoniana plantations in southern China. Using a chronosequence approach, we found that biomass of each component increased with aging while its proportion decreased except stem-wood. Nutrient pools varied with biomass pools except for foliage. For all harvest intensities...

  13. Nutrient export by rivers to the coastal waters of China: management strategies and future trends

    NARCIS (Netherlands)

    Qu, Hong Juan; Kroeze, C.

    2012-01-01

    We analyzed past and future trends in river export of dissolved nitrogen (N) and phosphorus (P) to the coastal waters of China, for a selection of rivers, as calculated by the Global NEWS models (Nutrient Export from WaterSheds). Over the period 1970–2000, river export of dissolved nutrients

  14. Nutrient Management Approaches and Tools for Dairy farms in Australia and the USA.

    Science.gov (United States)

    In Australia and the USA, nutrient imports and accumulation on dairy farms can be a problem and may pose a threat to the greater environment. While the major nutrient imports onto dairy farms (i.e. fertilizer and feed) and exports (i.e. milk and animals) are generally the same for confinement-based ...

  15. Nutrient export by rivers to the coastal waters of China: management strategies and future trends

    NARCIS (Netherlands)

    Qu, Hong Juan; Kroeze, C.

    2012-01-01

    We analyzed past and future trends in river export of dissolved nitrogen (N) and phosphorus (P) to the coastal waters of China, for a selection of rivers, as calculated by the Global NEWS models (Nutrient Export from WaterSheds). Over the period 1970–2000, river export of dissolved nutrients increas

  16. Whole farm management to reduce nutrient losses from dairy farms: a simulation study

    NARCIS (Netherlands)

    Rotz, C.A.; Oenema, J.; Keulen, van H.

    2003-01-01

    Whole farm simulation provides a tool for evaluating the impact of nutrient conservation technologies and strategies on dairy farms. A farm simulation model was verified by simulating the production and nutrient flows of the De Marke experimental dairy farm in the Netherlands. Technology such as a

  17. Whole Farm Management to Reduce Nutrient Losses From Dairy Farms: A Simulation Study

    NARCIS (Netherlands)

    Rotz, C.A.; Oenema, J.; Keulen, van H.

    2006-01-01

    Whole-farm simulation provides a tool for evaluating long-term impacts of nutrient conservation technologies and strategies on dairy farms. A farm simulation model was verified to predict the production and nutrient flows of the De Marke experimental dairy farm in the Netherlands. On this farm,

  18. 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.

  19. [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.

  20. Managing invasive plants in natural areas: Moving beyond weed control

    Science.gov (United States)

    Dean Pearson; Yvette Ortega

    2009-01-01

    Exotic invasive plants present one of the greatest challenges to natural resource management. These weeds can alter entire communities and ecosystems, substantially degrading important ecosystem services such as forage for wild and domestic herbivores, water and soil quality, recreational values, and wildlife habitat. Traditionally, weed management in natural areas has...