WorldWideScience

Sample records for animal-based agriculture phosphorus

  1. Phosphorus, Agriculture & The Environment

    OpenAIRE

    Mullins, Gregory Lee

    2009-01-01

    Discusses potential environmental impacts of phosphorus, the functions of phosphorus in plants and animals, and the soil phosphorus cycle. Notes methods for controlling phosphorus losses to surface waters

  2. Regulating phosphorus from the agricultural sector

    DEFF Research Database (Denmark)

    Hansen, Line Block; Hansen, Lars Gårn; Rubæk, Gitte Holton

    2010-01-01

    do not take into account the importance of P already stored in the soils. Phosphorus stored in the soils is the major source of P losses to surface waters, but at the same time crucial for the soils ability to sustain a viable crop production. Even if measures on P losses from agricultural areas...... could be obtained, such measures may not truly reflect stocks and hence potential risks associated with eg erosion, run-off or climate change. This calls for a method which handles the continuous supply of P to the soils (the current flow effect), P accumulated in the soil (a stock effect......  Loss of phosphorus (P) from agricultural areas is one of the main contributors to eutrophication of water systems in many European countries. Regulatory systems such as ambient taxes or discharge taxes which are suitable for regulation of N are insufficient for regulating P because these systems...

  3. Agricultural trade and the global phosphorus cycle

    Science.gov (United States)

    Schipanski, M.; Bennett, E.; Riskin, S.; Porder, S.

    2012-12-01

    Trends of increasing agricultural trade, increased concentration of livestock production systems, and increased human consumption of livestock products influence the distribution of nutrients across the global landscape. Phosphorus (P) represents a unique management challenge as we are rapidly depleting mineable reserves of this essential and non-renewable resource. At the same time, its overuse can lead to pollution of aquatic ecosystems. We analyzed the relative contributions of food crop, feed crop, and livestock product trade to P flows through agricultural soils for twelve countries from 1961 to 2007. We then used case studies of P fertilizer use in the world's three major soybean export regions: Iowa (USA), Mato Grosso (Brazil), and Buenos Aires (Argentina) to examine the influence of historical P management and soil types on agriculture's environmental consequences. Due to the intensification of agricultural production, average soil surface P balances more than tripled from 6 to 21 kg P per ha between 1961 and 2007 for the twelve study countries. Consequently, countries that are primarily agricultural exporters carried increased risks for water pollution or, for Argentina, reduced soil fertility due to soil P mining to support exports. In 2007, nations imported food and feed from regions with higher apparent P fertilizer use efficiencies than if those crops were produced domestically. However, this was largely because imports were sourced from regions depleting soil P resources to support export crop production. In addition, the pattern of regional specialization and intensification of production systems also reduced the potential to recycle P resources, with greater implications for livestock production than crop production. In a globalizing world, it will be increasingly important to integrate biophysical constraints of our natural resources and environmental impacts of agricultural systems into trade policy and agreements and to develop mechanisms that

  4. Animal-based agriculture, phosphorus management and water quality in Brazil: options for the future Produção animal, manejo de fósforo e qualidade da água no Brasil: opções para o futuro

    Directory of Open Access Journals (Sweden)

    Francirose Shigaki

    2006-04-01

    Full Text Available Eutrophication has become a major threat to water quality in the U.S., Europe, and Australasia. In most cases, freshwater eutrophication is accelerated by increased inputs of phosphorus (P, of which agricultural runoff is now a major contributor, due to intensification of crop and animal production systems since the early 1990s'. Once little information is available on the impacts of Brazilian agriculture in water quality, recent changes in crop and animal production systems in Brazil were evaluated in the context of probable implications of the fate of P in agriculture. Between 1993 and 2003, there was 33% increase in the number of housed animals (i.e., beef, dairy cows, swine, and poultry, most in the South Region (i.e., Paraná, Rio Grande do Sul, and Santa Catarina States, where 43 and 49% of Brazil's swine and poultry production is located, respectively. Although grazing-based beef production is the major animal production system in Brazil, it is an extensive system, where manure is deposited over grazed pastures; confined swine and poultry are intensive systems, producing large amounts of manure in small areas, which can be considered a manageable resource. This discussion will focus on swine and poultry farming. Based on average swine (100 kg and poultry weights (1.3 kg, daily manure production (4.90 and 0.055 kg per swine and poultry animal unit, respectively, and manure P content (40 and 24 g kg-1 for swine and poultry, respectively, an estimated 2.5 million tones of P in swine and poultry manure were produced in 2003. Mostly in the South and Southeast regions of Brazil (62%, which represent only 18% of the country's land area. In the context of crop P requirements, there was 2.6 times more P produced in manure (1.08 million tones than applied as fertilizer (0.42 million tonnes in South Brazil in 2003. If it is assumed that fertilizer P use represents P added to meet crop needs and accounts for P sorbed by soil in unavailable forms each

  5. Phosphorus accumulation and spatial distribution in agricultural soils in Denmark

    DEFF Research Database (Denmark)

    Rubæk, Gitte Holton; Kristensen, Kristian; Olesen, S E;

    2013-01-01

    Over the past century, phosphorus (P) has accumulated in Danish agricultural soils. We examined the soil P content and the degree of P saturation in acid oxalate (DPS) in 337 agricultural soil profiles and 32 soil profiles from deciduous forests sampled at 0–0.25, 0.25–0.50, 0.50–0.75 and 0...

  6. Phosphorus

    OpenAIRE

    Linderholm, Kersti

    2012-01-01

    Phosphorus is an essential element for plants, animals and humans and is also a scarce resource as a raw material for fertilizer production. The flows of phosphorus to and from Swedish agriculture and food chain was investigated with a material flow analysis (MFA). The fertilizer value of recycled phosphorus in chemically precipitated sewage sludge, biological sludge, mineral fertilizer and ash was investigated in a three-year field experiment. The impact of different phosphorus fertilizers o...

  7. Diversity enhances agricultural productivity via rhizosphere phosphorus facilitation on phosphorus-deficient soils.

    Science.gov (United States)

    Li, Long; Li, Shu-Min; Sun, Jian-Hao; Zhou, Li-Li; Bao, Xing-Guo; Zhang, Hong-Gang; Zhang, Fu-Suo

    2007-07-01

    Intercropping, which grows at least two crop species on the same pieces of land at the same time, can increase grain yields greatly. Legume-grass intercrops are known to overyield because of legume nitrogen fixation. However, many agricultural soils are deficient in phosphorus. Here we show that a new mechanism of overyielding, in which phosphorus mobilized by one crop species increases the growth of a second crop species grown in alternate rows, led to large yield increases on phosphorus-deficient soils. In 4 years of field experiments, maize (Zea mays L.) overyielded by 43% and faba bean (Vicia faba L.) overyielded by 26% when intercropped on a low-phosphorus but high-nitrogen soil. We found that overyielding of maize was attributable to below-ground interactions between faba bean and maize in another field experiment. Intercropping with faba bean improved maize grain yield significantly and above-ground biomass marginally significantly, compared with maize grown with wheat, at lower rates of P fertilizer application (112.5 kg of P(2)O(5) per hectare). By using permeable and impermeable root barriers, we found that maize overyielding resulted from its uptake of phosphorus mobilized by the acidification of the rhizosphere via faba bean root release of organic acids and protons. Faba bean overyielded because its growth season and rooting depth differed from maize. The large increase in yields from intercropping on low-phosphorus soils is likely to be especially important on heavily weathered soils.

  8. Substantial dust loss of bioavailable phosphorus from agricultural soils

    Science.gov (United States)

    Katra, Itzhak; Gross, Avner; Swet, Nitzan; Tanner, Smadar; Krasnov, Helena; Angert, Alon

    2016-04-01

    Phosphorus (P) is an essential element in terrestrial ecosystems. Knowledge on the role of dust in the biogeochemical cycling of phosphorus is very limited with no quantitative information on aeolian (by wind) P fluxes from soils. The aim of this study is to focus on P cycling via dust emissions under common land-use practices in an arid environment by integration of sample analyses and aeolian experiments. The experiments indicate significant P fluxes by PM10 dust due to agricultural land use. Even in a single wind-dust event at moderate velocity (7.0 m s-1), P flux in conventional agricultural fields can reach 1.83 kg km-2, that accumulates to a considerable amount per year at a regional scale. The results highlight a negative yearly balance in P content (up to hundreds kg km-2) in all agricultural soils, and thus more P nutrition is required to maintain efficient yield production. In grazing areas where no P nutrition is applied, the soil degradation process can lead to desertification. Emission of P from soil dust sources has significant implications for soil nutrient resources and management strategies in agricultural regions as well as for loading to the atmosphere and global biogeochemical cycles.

  9. Substantial dust loss of bioavailable phosphorus from agricultural soils

    Science.gov (United States)

    Katra, Itzhak; Gross, Avner; Swet, Nitzan; Tanner, Smadar; Krasnov, Helena; Angert, Alon

    2016-04-01

    Phosphorus (P) is an essential element in terrestrial ecosystems. Knowledge on the role of dust in the biogeochemical cycling of phosphorus is very limited with no quantitative information on aeolian (by wind) P fluxes from soils. The aim of this study is to focus on P cycling via dust emissions under common land-use practices in an arid environment by integration of sample analyses and aeolian experiments. The experiments indicate significant P fluxes by PM10 dust due to agricultural land use. Even in a single wind-dust event at moderate velocity (7.0 m s‑1), P flux in conventional agricultural fields can reach 1.83 kg km‑2, that accumulates to a considerable amount per year at a regional scale. The results highlight a negative yearly balance in P content (up to hundreds kg km‑2) in all agricultural soils, and thus more P nutrition is required to maintain efficient yield production. In grazing areas where no P nutrition is applied, the soil degradation process can lead to desertification. Emission of P from soil dust sources has significant implications for soil nutrient resources and management strategies in agricultural regions as well as for loading to the atmosphere and global biogeochemical cycles.

  10. Phosphorus Recycling from an Unexplored Source by Polyphosphate Accumulating Microalgae and Cyanobacteria-A Step to Phosphorus Security in Agriculture.

    Science.gov (United States)

    Mukherjee, Chandan; Chowdhury, Rajojit; Ray, Krishna

    2015-01-01

    Phosphorus (P), an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50-100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp., and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale. PMID:26733966

  11. Phosphorus recycling from an unexplored source by polyphosphate accumulating microalgae and cyanobacteria – a step to phosphorus security in agriculture

    Directory of Open Access Journals (Sweden)

    Chandan eMukherjee

    2015-12-01

    Full Text Available Phosphorus (P, an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50-100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp. and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale.

  12. Modeling a phosphorus credit trading program in an agricultural watershed.

    Science.gov (United States)

    Corrales, Juliana; Naja, G Melodie; Bhat, Mahadev G; Miralles-Wilhelm, Fernando

    2014-10-01

    Water quality and economic models were linked to assess the economic and environmental benefits of implementing a phosphorus credit trading program in an agricultural sub-basin of Lake Okeechobee watershed, Florida, United States. The water quality model determined the effects of rainfall, land use type, and agricultural management practices on the amount of total phosphorus (TP) discharged. TP loadings generated at the farm level, reaching the nearby streams, and attenuated to the sub-basin outlet from all sources within the sub-basin, were estimated at 106.4, 91, and 85 mtons yr(-)(1), respectively. Almost 95% of the TP loadings reaching the nearby streams were attributed to agriculture sources, and only 1.2% originated from urban areas, accounting for a combined TP load of 87.9 mtons yr(-)(1). In order to compare a Least-Cost Abatement approach to a Command-and-Control approach, the most cost effective cap of 30% TP reduction was selected, and the individual allocation was set at a TP load target of 1.6 kg ha(-1) yr(-1) (at the nearby stream level). The Least-Cost Abatement approach generated a potential cost savings of 27% ($1.3 million per year), based on an optimal credit price of $179. Dairies (major buyer), ornamentals, row crops, and sod farms were identified as potential credit buyers, whereas citrus, improved pastures (major seller), and urban areas were identified as potential credit sellers. Almost 81% of the TP credits available for trading were exchanged. The methodology presented here can be adapted to deal with different forms of trading sources, contaminants, or other technologies and management practices. PMID:24907668

  13. Phosphorus transport in agricultural subsurface drainage: a review.

    Science.gov (United States)

    King, Kevin W; Williams, Mark R; Macrae, Merrin L; Fausey, Norman R; Frankenberger, Jane; Smith, Douglas R; Kleinman, Peter J A; Brown, Larry C

    2015-03-01

    Phosphorus (P) loss from agricultural fields and watersheds has been an important water quality issue for decades because of the critical role P plays in eutrophication. Historically, most research has focused on P losses by surface runoff and erosion because subsurface P losses were often deemed to be negligible. Perceptions of subsurface P transport, however, have evolved, and considerable work has been conducted to better understand the magnitude and importance of subsurface P transport and to identify practices and treatments that decrease subsurface P loads to surface waters. The objectives of this paper were (i) to critically review research on P transport in subsurface drainage, (ii) to determine factors that control P losses, and (iii) to identify gaps in the current scientific understanding of the role of subsurface drainage in P transport. Factors that affect subsurface P transport are discussed within the framework of intensively drained agricultural settings. These factors include soil characteristics (e.g., preferential flow, P sorption capacity, and redox conditions), drainage design (e.g., tile spacing, tile depth, and the installation of surface inlets), prevailing conditions and management (e.g., soil-test P levels, tillage, cropping system, and the source, rate, placement, and timing of P application), and hydrologic and climatic variables (e.g., baseflow, event flow, and seasonal differences). Structural, treatment, and management approaches to mitigate subsurface P transport-such as practices that disconnect flow pathways between surface soils and tile drains, drainage water management, in-stream or end-of-tile treatments, and ditch design and management-are also discussed. The review concludes by identifying gaps in the current understanding of P transport in subsurface drains and suggesting areas where future research is needed. PMID:26023966

  14. Phosphorus losses from agricultural areas in river basins; effects and uncertainties of targeted mitigation measures

    NARCIS (Netherlands)

    Kronvang, B.; Bechmann, M.; Lundekvam, H.; Behrendt, H.; Rubaek, G.H.; Schoumans, O.F.; Syversen, N.; Andersen, H.E.; Hoffmann, C.C.

    2005-01-01

    In this paper we show the quantitative and relative importance of phosphorus (P) losses from agricultural areas within European river basins and demonstrate the importance of P pathways, linking agricultural source areas to surface water at different scales. Agricultural P losses are increasingly im

  15. Phosphorus cycling in Montreal's food and urban agriculture systems.

    Directory of Open Access Journals (Sweden)

    Geneviève S Metson

    Full Text Available Cities are a key system in anthropogenic phosphorus (P cycling because they concentrate both P demand and waste production. Urban agriculture (UA has been proposed as a means to improve P management by recycling cities' P-rich waste back into local food production. However, we have a limited understanding of the role UA currently plays in the P cycle of cities or its potential to recycle local P waste. Using existing data combined with surveys of local UA practitioners, we quantified the role of UA in the P cycle of Montreal, Canada to explore the potential for UA to recycle local P waste. We also used existing data to complete a substance flow analysis of P flows in the overall food system of Montreal. In 2012, Montreal imported 3.5 Gg of P in food, of which 2.63 Gg ultimately accumulated in landfills, 0.36 Gg were discharged to local waters, and only 0.09 Gg were recycled through composting. We found that UA is only a small sub-system in the overall P cycle of the city, contributing just 0.44% of the P consumed as food in the city. However, within the UA system, the rate of recycling is high: 73% of inputs applied to soil were from recycled sources. While a Quebec mandate to recycle 100% of all organic waste by 2020 might increase the role of UA in P recycling, the area of land in UA is too small to accommodate all P waste produced on the island. UA may, however, be a valuable pathway to improve urban P sustainability by acting as an activity that changes residents' relationship to, and understanding of, the food system and increases their acceptance of composting.

  16. Approximating Phosphorus Leaching from Agricultural Organic Soils by Soil Testing.

    Science.gov (United States)

    Zheng, Z M; Zhang, T Q; Kessel, C; Tan, C S; O'Halloran, I P; Wang, Y T; Speranzini, D; Van Eerd, L L

    2015-11-01

    Phosphorus applied to soils in excess of crop requirement could create situations favorable to P enrichment in subsurface flow that contributes to eutrophication of surface water. This pathway of P loss can be more severe in muck (i.e., organic) soils where agricultural production is intensive. This study evaluated the suitability of various environmental and agronomic soil P tests initially designed for mineral soils to predict dissolved reactive P (DRP) in subsurface flow from organic soils. Intact soil columns were collected from 44 muck soils in Ontario to provide a wide range of soil test P levels. A lysimeter leaching study was conducted by evenly adding water in an amount equivalent to 5 mm of rainfall. The leachate DRP concentration was linearly related to soil water-extractable P and CaCl-extractable P with values of 0.90 and 0.93, respectively, and to Bray-1 P and FeO-impregnated filter paper extractable P in a split-line model with a change point. Mehlich-3 P and Olsen P, a method recommended for agronomic P calibration in Ontario, were not related to leachate DRP concentration. All P sorption index (PSI) based degree of P saturation (DPS) values were closely related to leachate DRP in split-line models, with the DPS indices expressed as Bray-1 P/PSI and FeO-P/PSI having the highest correlation with leachate DRP concentration. Because it is desirable from practical and economic standpoints that the environmental risk assessment shares the same soil test with agronomic P calibration, the two PSI-based DPS indices as presented can be considered as environmental risk indicators of DRP subsurface loss from organic soils. PMID:26641339

  17. Assessment of In-Stream Phosphorus Dynamics in Agricultural Drainage Ditches

    Science.gov (United States)

    The intensive row crop agricultural systems in the Midwestern United States can enrich surface waters with nutrients. This project was conducted to evaluate the in-stream processing of P in agricultural ditches. Phosphorus injection studies were conducted at seven sites along three drainage ditches ...

  18. Can non-point phosphorus emissions from agriculture be regulated efficiently using input-output taxes?

    DEFF Research Database (Denmark)

    Hansen, Line Bloch; Hansen, Lars Gårn

    In many parts of Europe and North America, phosphorus loss from cultivated fields is threatening natural ecosystems. Though there are similarities to other non-point agricultural emissions like nitrogen that have been studied extensively, phosphorus is often characterised by the presence of large...... stocking capacities for phosphorus in farm soils and long time-lags between applications and emission. This makes it important to understand the dynamics of the phosphorus emission problem when designing regulatory systems. Using a model that reflects these dynamics, we evaluate alternative regulatory...... systems. Depending on the proportions of different types of farms in the agricultural sector, we find that an input-output tax system may be close to efficient, or in other cases must be supplemented with subsidy and manure reallocation schemes....

  19. Can non-point Phosphorus emissions from agriculture be regulated efficiently using input-output taxes?

    DEFF Research Database (Denmark)

    Hansen, Line Block; Hansen, Lars Gårn

    2014-01-01

    In many parts of Europe and North America, phosphorus loss from cultivated fields is threatening natural ecosystems. Though there are similarities to other non-point agricultural emissions like nitrogen that have been studied extensively, phosphorus is often characterized by the presence of large...... stocking capacities for phosphorus in farm soils and long time-lags between applications and emission. This makes it important to understand the dynamics of the phosphorus emission problem when designing regulatory systems. Using a model that reflects these dynamics, we evaluate alternative regulatory...... systems. Depending on the proportions of different types of farms in the agricultural sector, we find that an input-output tax system can be the core element of a close to efficient regulatory policy....

  20. The legacy of phosphorus: agriculture and future food security

    NARCIS (Netherlands)

    Sattari, S.Z.

    2014-01-01

    Growing global demand for food leads to increased concern regarding phosphorus (P), a finite and dwindling resource. Debate focuses on current production and use of phosphate rock rather than on the amount of P required to feed the world in the future. While the time scale of P depletion is debatabl

  1. [Soil Phosphorus Forms and Leaching Risk in a Typically Agricultural Catchment of Hefei Suburban].

    Science.gov (United States)

    Fan, Hui-hui; Li, Ru-zhong; Pei, Ting-ting; Zhang, Rui-gang

    2016-01-15

    To investigate the soil phosphorus forms and leaching risk in a typically agricultural catchment of Ershibu River in Hefei Suburban, Chaohu Lake basin, 132 surface soil samples were collected from the catchment area. The spatial distribution of total phosphorus (TP) and bio-available phosphorus (Bio-P), and the spatial variability of soil available phosphorus (Olsen-P) and easy desorption phosphorus (CaCl2-P) were analyzed using the Kriging technology of AreGIS after speciation analysis of soil phosphorus. Moreover, the enrichment level of soil phosphorus was studied, and the phosphorus leaching risk was evaluated through determining the leaching threshold value of soil phosphorus. The results showed that the samples with high contents of TP and Bio-P mainly located in the upstream of the left tributary and on the right side of local area where two tributaries converged. The enrichment rates of soil phosphorus forms were arranged as follows: Ca-P (15.01) > OP (4.16) > TP (3. 42) > IP (2.94) > Ex-P (2.76) > Fe/Al-P (2.43) > Olsen-P (2.34). The critical value of Olsen-P leaching was 18.388 mg x kg(-1), and the leaching samples with values higher than the threshold value accounted for 16.6% of total samples. Generally, the high-risk areas mainly occurred in the upstream of the left tributary, the middle of the right tributary and the local area of the downstream of the area where two tributaries converged.

  2. Future agriculture with minimized phosphorus losses to waters: Research needs and direction.

    Science.gov (United States)

    Sharpley, Andrew N; Bergström, Lars; Aronsson, Helena; Bechmann, Marianne; Bolster, Carl H; Börling, Katarina; Djodjic, Faruk; Jarvie, Helen P; Schoumans, Oscar F; Stamm, Christian; Tonderski, Karin S; Ulén, Barbro; Uusitalo, Risto; Withers, Paul J A

    2015-03-01

    The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities.

  3. Organic Phosphorus Characterisation in Agricultural Soils by Enzyme Addition Assays

    Science.gov (United States)

    Jarosch, Klaus; Frossard, Emmanuel; Bünemann, Else K.

    2013-04-01

    Phosphorus (P) is a non-renewable resource and it is a building block of many molecules indispensable for life. Up to 80 per cent of total soil P can be in organic form. Hydrolysability and thereby availability to plants and microorganisms differ strongly among the multitude of chemical forms of soil organic P. A recent approach to characterise organic P classes is the addition of specific enzymes which hydrolyse organic P to inorganic orthophosphate, making it detectable by colorimetry. Based on the substrate specificity of the added enzymes, conclusions about the hydrolysed forms of organic P can then be made. The aim of this study was to determine the applicability of enzyme addition assays for the characterisation of organic P species in soil:water suspensions of soils with differing properties. To this end, ten different soil samples originating from four continents, with variable pH (in water) values (4.2-8.0), land management (grassland or cropped land) and P fertilization intensity were analysed. Three different enzymes were used (acid phosphatase, nuclease and phytase). Acid phosphatase alone or in combination with nuclease was applied to determine the content of P in simple monoesters (monoester-like P) and P in DNA (DNA-like P), while P hydrolysed from myo-inositol hexakisphosphate (Ins6P-like P) was calculated from P release after incubation with phytase minus P release by acid phosphatase. To reduce sorption of inorganic P on soil particles of the suspension, especially in highly weathered soils, soil specific EDTA additions were determined in extensive pre-tests. The results of these pre-tests showed that recoveries of at least 30 per cent could be achieved in all soils. Thus, detection of even small organic P pools, such as DNA-like P, was possible in all soils if a suitable EDTA concentration was chosen. The enzyme addition assays provided information about the hydrolysable quantities of the different classes of soil organic P compounds as affected

  4. Past, present, and future use of phosphorus in Chinese agriculture and its influence on phosphorus losses.

    Science.gov (United States)

    Li, Haigang; Liu, Jian; Li, Guohua; Shen, Jianbo; Bergström, Lars; Zhang, Fusuo

    2015-03-01

    Large inputs of phosphorus (P) in chemical fertilizers and feed supplements since 1978 have improved soil P status in arable land in China, but have also created challenges by increasing P concentrations in manure and exacerbating water quality degradation. Arable land in China can be divided into five management zones based on soil P chemistry, with 15-92 % of arable land having lower P status than the agronomic optimum and 0.3-7.2 % having severe risks of P leaching losses. A scenario analysis of soil P budget and agronomic P demand during 2011-2030 highlighted the great pressure China faces in sustainable P management and the need for drastic changes in current practices. This includes new policies to reduce P supplementation of feed and improved P use efficiency by livestock and programs to expand the adoption of appropriate fertilization, soil conservation, and drainage management practices to minimize P losses.

  5. SEASONAL CHANGES IN PHOSPHORUS LOAD FLOWING OUT OF SMALL AGRICULTURAL CATCHMENTS

    Directory of Open Access Journals (Sweden)

    Krzysztof Pulikowski

    2014-12-01

    Full Text Available In this article distribution of monthly phosphorus loads flowing out of two agricultural catchments which are located in different physiographic conditions of Lower Silesia was analysed. Loads of phosphorus runoff from the catchment located in the piedmont part of Lower Silesia in each month rarely exceed 0.10 kg P ∙ ha-1. The size of annual load is determined by loads obtained in two months of early spring. Much lower loads obtained for lowland catchment, located near Wroclaw. Values ​​calculated for each month rarely exceed the value of 0.01 kg P ∙ ha-1. Culmination of loads bringing away is a bit more extended in a time compared to the catchment located on Sudety Mts. Foreland. Much higher loads are observed during the period from January to April – this period has a major impact on the size of phosphorus load that flows out from this catchment during whole hydrological year. The obtained results clearly indicate that the threat of watercourses and water reservoirs supply in phosphorus compounds from agricultural land is periodic and it is particularly high during early spring. Phosphorus load flowing out from the analyzed catchments is very diverse. From facility located on Sudety Foothill in hydrological year, during research period, flowed away average 0.81 kg P ∙ ha-1. Significantly lower values were obtained for second facility and it was average 0.15 kg P ∙ ha-1 during a year. The size of load discharged during a year is largely determined by amount of phosphorus load flowing out during winter half of the year (from XI to IV. In case of foothill catchment in this period flowed out average 0.56 kg P ∙ ha-1, which presents 69% of annual load and in lowland catchment this percentage was even slightly higher and was 73%.

  6. Phosphorus Treated Coal Combustion Products (CCP-bottom ash) as an Agricultural Source of Phosphorus

    Science.gov (United States)

    Junfeng, Shen; Powell, M. A.; Hayden, D. B.

    Coal combustion products (CCP or "ash") have been seen to be beneficial for improving soil quality and increasing vegetative yields. Owing to their structure with more holes, they are also potential carriers of plant nutrients. The bottom ash from the Lambton Generating Station, Sarnia, Ontario, Canada was treated for 66 hours in 0.10 mol/L P solutions prepared from NaH 2PO 4, which resulted in the ash adsorbing 784 µg/g of phosphorus. The ash was mixed with quartz sand and/or non P-loaded ash from the same source to provide a set of growth media that contained 10%, 25%, 50%, 75%, and 100% of the recommended dose of P (50 µg/g) for maize. Biomass yields at 26, 34, and 46 days after planting were compared with control (non-doped ash) and fertilized with 0-20-0 fertilizer. In general, growth media containing between 25% and 100% of the recommended P dose performed as well or better than the fertilized trials. 46 days after planting, the shoot fresh weight for the 50%, 75%, and 100% doped media were 39.46%, 42.73%, and 46.13%, respectively, greater compared to fertilized trials. The shoot dry weight increased by 29.71%, 13.39%, and 28.87%, respectively. Also, root fresh and dry weight increased averagely by 16.62% and 14.03%. These results implied that coal ashes are a better carrier for P uptaking, and P-loaded ash can be a good additive for sand soil improvement.

  7. Four decades of post-agricultural forest development have caused major redistributions of soil phosphorus fractions

    DEFF Research Database (Denmark)

    Schrijver, An De; Vesterdal, Lars; Hansen, Karin Irene;

    2012-01-01

    Fertilisation of agricultural land causes an accumulation of nutrients in the top soil layer, among which phosphorus (P) is particularly persistent. Changing land use from farmland to forest affects soil properties, but changes in P pools have rarely been studied despite their importance to forest...... ecosystem development. Here, we describe the redistributions of the P pools in a four-decadal chronosequence of post-agricultural common oak (Quercus robur L.) forests in Belgium and Denmark. The aim was to assess whether forest age causes a repartitioning of P throughout the various soil P pools (labile P...

  8. Phosphorus release from agriculture to surface waters: past, present and future in China.

    Science.gov (United States)

    Chen, M; Chen, J

    2008-01-01

    So far, there is no clear picture at national level regarding the severity, spatial distribution, trend and driving forces of phosphorus (P) release from agriculture to surface waters in China, which presents a major obstacle for surface water quality management and relevant policy-making. By applying a proposed Activity-Unit-Balance (AUB) methodology, this paper retrospects and prospects phosphorus release from agricultural activities to surface waters from 1978 to 2050 in China. Modelling results reveal that P load from agriculture has increased 3.4 times during 1978-2005 and will increase by 1.8 times during 2005-2050. Although major contribution factors are mineral fertiliser application (MFA) and livestock feeding activities (LFAs), LFAs will be the single largest source of increased total P load in the next decades. Most importantly, agricultural pollution in China is spatially overlapped with industrial and domestic pollution, and regions in the southeast to "Heihe-Tengchong" line have to be confronted with an austere challenge to control and manage industrial and domestic pollution as well as pollution from agriculture at present and in future.

  9. Using continuous monitoring of physical parameters to better estimate phosphorus fluxes in a small agricultural catchment

    Science.gov (United States)

    Minaudo, Camille; Dupas, Rémi; Moatar, Florentina; Gascuel-Odoux, Chantal

    2016-04-01

    Phosphorus fluxes in streams are subjected to high temporal variations, questioning the relevance of the monitoring strategies (generally monthly sampling) chosen to assist EU Directives to capture phosphorus fluxes and their variations over time. The objective of this study was to estimate the annual and seasonal P flux uncertainties depending on several monitoring strategies, with varying sampling frequencies, but also taking into account simultaneous and continuous time-series of parameters such as turbidity, conductivity, groundwater level and precipitation. Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Total Suspended Solids (TSS) concentrations were surveyed at a fine temporal frequency between 2007 and 2015 at the outlet of a small agricultural catchment in Brittany (Naizin, 5 km2). Sampling occurred every 3 to 6 days between 2007 and 2012 and daily between 2013 and 2015. Additionally, 61 storms were intensively surveyed (1 sample every 30 minutes) since 2007. Besides, water discharge, turbidity, conductivity, groundwater level and precipitation were monitored on a sub-hourly basis. A strong temporal decoupling between SRP and particulate P (PP) was found (Dupas et al., 2015). The phosphorus-discharge relationships displayed two types of hysteretic patterns (clockwise and counterclockwise). For both cases, time-series of PP and SRP were estimated continuously for the whole period using an empirical model linking P concentrations with the hydrological and physic-chemical variables. The associated errors of the estimated P concentrations were also assessed. These « synthetic » PP and SRP time-series allowed us to discuss the most efficient monitoring strategies, first taking into account different sampling strategies based on Monte Carlo random simulations, and then adding the information from continuous data such as turbidity, conductivity and groundwater depth based on empirical modelling. Dupas et al., (2015, Distinct export dynamics for

  10. Landscape planning for agricultural nonpoint source pollution reduction III: Assessing phosphorus and sediment reduction potential

    Science.gov (United States)

    Diebel, M.W.; Maxted, J.T.; Robertson, D.M.; Han, S.; Vander Zanden, M. J.

    2009-01-01

    Riparian buffers have the potential to improve stream water quality in agricultural landscapes. This potential may vary in response to landscape characteristics such as soils, topography, land use, and human activities, including legacies of historical land management. We built a predictive model to estimate the sediment and phosphorus load reduction that should be achievable following the implementation of riparian buffers; then we estimated load reduction potential for a set of 1598 watersheds (average 54 km2) in Wisconsin. Our results indicate that land cover is generally the most important driver of constituent loads in Wisconsin streams, but its influence varies among pollutants and according to the scale at which it is measured. Physiographic (drainage density) variation also influenced sediment and phosphorus loads. The effect of historical land use on present-day channel erosion and variation in soil texture are the most important sources of phosphorus and sediment that riparian buffers cannot attenuate. However, in most watersheds, a large proportion (approximately 70%) of these pollutants can be eliminated from streams with buffers. Cumulative frequency distributions of load reduction potential indicate that targeting pollution reduction in the highest 10% of Wisconsin watersheds would reduce total phosphorus and sediment loads in the entire state by approximately 20%. These results support our approach of geographically targeting nonpoint source pollution reduction at multiple scales, including the watershed scale. ?? 2008 Springer Science+Business Media, LLC.

  11. Drainage filter technologies to mitigate site-specific phosphorus losses in agricultural drainage discharge

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Canga, Eriona;

    filters and constructed wetlands (CWs). Various natural and industrial P filter substrates (granulated Fe-oxides, crushed seashells, Filtralite-PTM, granulated lime, calcined diatomitic earth) have been tested for their affinity and long-term capacity to reduce inlet P concentrations to below...... environmental threshold values (long-term P-loading the sensitivity of flow-rate on P retention increased and further indicated......Losses of phosphorus (P) in drainage waters contribute an estimated 33% to the total agricultural P load in Denmark. Mitigating agricultural P losses is challenging, as critical P losses comprise only a very small fraction of actual soil P contents and are not directly related to fertilizer P input...

  12. Legacy phosphorus and no tillage agriculture in tropical oxisols of the Brazilian savanna.

    Science.gov (United States)

    Rodrigues, Marcos; Pavinato, Paulo Sergio; Withers, Paul John Anthony; Teles, Ana Paula Bettoni; Herrera, Wilfrand Ferney Bejarano

    2016-01-15

    Crop production in the Brazilian Cerrado is limited by soil phosphorus (P) supply without large inputs of inorganic P fertilizer, which may become more costly and scarce in the future. Reducing dependency on fertilizer P requires a greater understanding of soil P supply in the highly weathered soils in this important agricultural region. We investigated the impact of no tillage (NT) and conventional tillage (CT) agriculture on accumulated (legacy) soil P and P forms in four long-term sites. Compared to the native savanna soils, tilled soils receiving regular annual P fertilizer inputs (30-50 kg P ha(-1)) increased all forms of inorganic and organic P, except highly recalcitrant P associated with the background lithology. However, 70-85% of the net added P was bound in moderately labile and non-labile forms associated with Fe/Al oxyhydroxides rather than in plant available forms. Under NT agriculture, organic P forms and labile and non-labile inorganic P forms were all significantly (PCerrado soils that could be better exploited to reduce dependency on imports of finite phosphate rock. No tillage agriculture confers a positive albeit relatively small benefit for soil P availability and overall soil function. PMID:26351200

  13. SIMPLE: assessment of non-point phosphorus pollution from agricultural land to surface waters by means of a new methodology.

    Science.gov (United States)

    Schoumans, O F; Mol-Dijkstra, J; Akkermans, L M W; Roest, C W J

    2002-01-01

    In the past, environmental Phosphorus (P) parameters like soil P indices have been used to catogorize the potential risk of P losses from agricultural land. In order to assess the actual risk of P pollution of groundwater and surface waters, dynamic process oriented soil and water quality models have been frequently used. Recently, an approximating model for phosphorus, called SIMPLE, has been developed. This model approximates the output from a complex dynamic water quality model. The approximating model is called a metamodel. This simple P-model proves to be a powerful tool for quick assessment of the risk of P pollution from agricultural land to surface waters. PMID:12079100

  14. Phosphorus dynamics in lowland streams as a response to climatic, hydrological and agricultural land use gradients

    Directory of Open Access Journals (Sweden)

    G. Goyenola

    2015-03-01

    Full Text Available Climate and hydrology are relevant control factors for determining the timing and amount of nutrient losses from agricultural fields to freshwaters. In this study, we evaluated the effect of agricultural intensification on the concentrations, dynamics and export of phosphorus (P in streams in two contrasting climate and hydrological regimes (temperate Denmark and subtropical Uruguay. We applied two alternative nutrient sampling programmes (high frequency composite sampling and low frequency instantaneous-grab sampling and three alternative methods to estimate exported P from the catchments. A source apportionment model was applied to evaluate the contribution derived from point and diffuse sources in all four catchments studied. Climatic and hydrological characteristics of catchments expressed as flow responsiveness (flashiness, exerted control on catchment and stream TP dynamics, having consequences that were more significant than the outcome of different TP monitoring and export estimation strategies. The impact of intensification of agriculture differed between the two contrasting climate zones. Intensification had a significant impact on subtropical climate with much higher total (as high as 4436 μg P L−1, particulate, dissolved and reactive soluble P concentrations and higher P export (as high as 5.20 kg P ha−1 year−1. However, we did not find an increased contribution of particulate P to total P as consequence of higher stream flashiness and intensification of agriculture. The high P concentrations at low flow and predominance of dissolved P in subtropical streams actually exacerbate the environmental and sanitary risks associated with eutrophication. In the other hand, temperate intensively farmed stream had lower TP than extensively farmed stream. Our results suggest that the lack of environmental regulations of agricultural production has more severe consequences on water quality, than climatic and hydrological differences

  15. A watershed modeling framework for phosphorus loading from residential and agricultural sources.

    Science.gov (United States)

    Sinclair, Andrew; Jamieson, Rob; Madani, Ali; Gordon, Robert J; Hart, William; Hebb, Dale

    2014-07-01

    Phosphorus (P) loading from residential onsite wastewater systems (OWSs) into neighboring surface waters is a poorly understood process in rural watersheds; this can be further challenged when rural residential dwellings are intermixed with agricultural land use. The objectives of this research were (i) to design a P onsite wastewater simulator (POWSIM) to assess P loads from individual or clusters of residential OWSs typically used in Nova Scotia, Canada; and (ii) to simulate OWS P loads in a mixed agricultural watershed (Thomas Brook Watershed [TBW], NS) using the Soil and Water Assessment Tool (SWAT) model in conjunction with POWSIM, to predict and compare P loading from agricultural and residential sources. The POWSIM loading tool has three computational components: (i) disposal field selection and treatment media mass calculation, (ii) disposal field P treatment dynamics, and (iii) soil subsurface plume P treatment dynamics. The combination TBW POWSIM and SWAT modeling approach produced a better simulation of baseflow total P (TP) loads in both a predominantly residential subcatchment and one dominated by agriculture than the SWAT model without POWSIM. The residential subcatchment had 48% of its average annual land use TP load (simulated) contributed by OWSs, whereas the agricultural subcatchment had 39%. Watershed-scale sensitivity analyses of POWSIM input parameters for 18- and 50-yr OWS operation periods found the P loading rate into the disposal field, long-term P removal rates in the disposal field and soil systems, soil maximum P sorption capacity, and mass of native soil involved in P treatment to be most sensitive. PMID:25603083

  16. Phosphorus dynamics in lowland streams as a response to climatic, hydrological and agricultural land use gradients

    Science.gov (United States)

    Goyenola, G.; Meerhoff, M.; Teixeira-de Mello, F.; González-Bergonzoni, I.; Graeber, D.; Fosalba, C.; Vidal, N.; Mazzeo, N.; Ovesen, N. B.; Jeppesen, E.; Kronvang, B.

    2015-03-01

    Climate and hydrology are relevant control factors for determining the timing and amount of nutrient losses from agricultural fields to freshwaters. In this study, we evaluated the effect of agricultural intensification on the concentrations, dynamics and export of phosphorus (P) in streams in two contrasting climate and hydrological regimes (temperate Denmark and subtropical Uruguay). We applied two alternative nutrient sampling programmes (high frequency composite sampling and low frequency instantaneous-grab sampling) and three alternative methods to estimate exported P from the catchments. A source apportionment model was applied to evaluate the contribution derived from point and diffuse sources in all four catchments studied. Climatic and hydrological characteristics of catchments expressed as flow responsiveness (flashiness), exerted control on catchment and stream TP dynamics, having consequences that were more significant than the outcome of different TP monitoring and export estimation strategies. The impact of intensification of agriculture differed between the two contrasting climate zones. Intensification had a significant impact on subtropical climate with much higher total (as high as 4436 μg P L-1), particulate, dissolved and reactive soluble P concentrations and higher P export (as high as 5.20 kg P ha-1 year-1). However, we did not find an increased contribution of particulate P to total P as consequence of higher stream flashiness and intensification of agriculture. The high P concentrations at low flow and predominance of dissolved P in subtropical streams actually exacerbate the environmental and sanitary risks associated with eutrophication. In the other hand, temperate intensively farmed stream had lower TP than extensively farmed stream. Our results suggest that the lack of environmental regulations of agricultural production has more severe consequences on water quality, than climatic and hydrological differences between the analysed

  17. Investigation of Soil Erosion and Phosphorus Transport within an Agricultural Watershed

    Science.gov (United States)

    Klik, A.; Jester, W.; Muhar, A.; Peinsitt, A.; Rampazzo, N.; Mentler, A.; Staudinger, B.; Eder, M.

    2003-04-01

    In a 40 ha agricultural used watershed in Austria, surface runoff, soil erosion and nutrient losses are measured spatially distributed with 12 small erosion plots. Crops during growing season 2002 are canola, corn, sunflower, winter wheat, winter barley, rye, sugar beets, and pasture. Canopy height and canopy cover are observed in 14-day intervals. Four times per year soil water content, shear stress and random roughness of the surface are measured in a 25 x 25 m grid (140 points). The same raster is sampled for soil texture analyses and content of different phosphorus fractions in the 0-10 cm soil depth. Spatially distributed data are used for geostatistical analysis. Along three transects hydrologic conditions of the hillslope position (top, middle, foot) are investigated by measuring soil water content and soil matrix potential. After erosive events erosion features (rills, deposition, ...) are mapped using GPS. All measured data will be used as input parameters for the Limburg Soil Erosion Model (LISEM).

  18. SIMPLE: assessment of non-point phosphorus pollution from agricultural land to surface waters by means of a new methodology

    NARCIS (Netherlands)

    Schoumans, O.F.; Mol-Dijkstra, J.P.; Akkermans, L.M.W.; Roest, C.W.J.

    2002-01-01

    In the past, environmental phosphorus (P) parameters like soil P indices have been used to catogorize the potential risk of P losses from agricultural land. In order to assess the actual risk of P pollution of groundwater and surface waters, dynamic process oriented soil and water quality models hav

  19. Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter

    This thesis is based on the results of a three-year long PhD-study at the Department of Communication and Psychology at Aalborg University. The thesis consist of five original papers, a book manuscript, as well as a linking text with the thesis’ research questions, research design, and summary...... experiments has been carried out, applying animation-based sketching in various contexts and at varying points in the design process. In the studies, I evaluate the viability of the approach, the practical integration into the design process, and map how consensus between stakeholders in design can...

  20. Using agricultural practices information for multiscale environmental assessment of phosphorus risk

    Science.gov (United States)

    Matos Moreira, Mariana; Lemercier, Blandine; Michot, Didier; Dupas, Rémi; Gascuel-Odoux, Chantal

    2015-04-01

    Phosphorus (P) is an essential nutrient for plant growth. In intensively farmed areas, excessive applications of animal manure and mineral P fertilizers to soils have raised both economic and ecological concerns. P accumulation in agricultural soils leads to increased P losses to surface waterbodies contributing to eutrophication. Increasing soil P content over time in agricultural soils is often correlated with agricultural practices; in Brittany (NW France), an intensive livestock farming region, soil P content is well correlated with animal density (Lemercier et al.,2008). Thus, a better understanding of the factors controlling P distribution is required to enable environmental assessment of P risk. The aim of this study was to understand spatial distribution of extractable (Olsen method) and total P contents and its controlling factors at the catchment scale in order to predict P contents at regional scale (Brittany). Data on soil morphology, soil tests (including P status, particles size, organic carbon…) for 198 punctual positions, crops succession since 20 years, agricultural systems, field and animal manure management were obtained on a well-characterized catchment (ORE Agrhys, 10 km²). A multivariate analysis with mixed quantitative variables and factors and a digital soil mapping approach were performed to identify variables playing a significant role in soil total and extractable P contents and distribution. Spatial analysis was performed by means of the Cubist model, a decision tree-based algorithm. Different scenarios were assessed, considering various panels of predictive variables: soil data, terrain attributes derived from digital elevation model, gamma-ray spectrometry (from airborne geophysical survey) and agricultural practices information. In the research catchment, mean extractable and total P content were 140.0 ± 63.4 mg/kg and 2862.7 ± 773.0 mg/kg, respectively. Organic and mineral P inputs, P balance, soil pH, and Al contents were

  1. Phosphorus export by runoff from agricultural field plots with different crop cover in Lake Taihu watershed

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Runoff and soil losses from agricultural fields are investigated as major nonpoint sources of phosphorus (P) entering lakes of Eastern China. There is relatively little information on P transport from ricefield and cropland of Lake Taihu watershed in Eastern China. Soil and P in surface runoff from a series of plots in the watershed were evaluated under simulated rainfall conditions. The objectives of this study were to evaluate theeffects of crop cover, slope, and fertilizer application on P concentrations in surface runoff and eroded soil. Accumulated sediment yields varied from 7.1 to 300 g/m2 for croplands, depending on management practices. For all experiment plots, weighted average concentrations of total-P (TP), dissolved P (DP) and particulate P (PP) are much higher than 0.02 mg/L, the limiting concentration in lake water. This result showed the potential contamination of lake water from agricultural surface runoff. Accumulated TP losses were 3.8 and 18.8 mg/m2 for ricefield and cropland, respectively. The estimated annual loss of TP was 0.74 kg/(hm2鷄) for cropland. Most of P loss is in PP form, which accounts for more than 90% of TP loss for cropland.

  2. Phosphorus use-efficiency of agriculture and food system in the US.

    Science.gov (United States)

    Suh, Sangwon; Yee, Scott

    2011-08-01

    The rapid increase in human mobilization of phosphorus has raised concerns on both its supply security and its impact on the environment. Increasing the efficiency of phosphorus use is an approach to mitigate the adverse impacts associated with phosphorus consumption. This study estimates the life-cycle phosphorus use-efficiency of the US food system. A framework for accounting phosphorus stocks and flows is developed, and the account was populated with data. A map of phosphorus stocks and flows around the US food system is drawn and phosphorus use-efficiency was calculated. The results show that only 15% of the total phosphorus extracted from nature for the provision of food is eventually ingested by humans and the rest is lost to the environment. Major losses occur during the livestock, meat and dairy production and crop cultivation stage, where about 66% of the total phosphorus extracted is lost to the environment. The results also show that other losses of phosphorus including household food waste, mining waste, and fertilizer manufacturing waste are not negligible, which constitute about 19% of the total phosphorus extracted for food purpose. A data quality assessment and sensitivity analysis was performed to identify data quality hotspots and to envisage effective measures to improving phosphorus use-efficiency. Improving yields of livestock and crop cultivation without additional phosphorus input and reducing household food waste are shown to be effective measures to improve life-cycle phosphorus use-efficiency. The results highlight the need of a concerted effort by all entities along the life-cycle for efficient use of phosphorus.

  3. Regime Shifts in Shallow Lakes: Responses of Cyanobacterial Blooms to Watershed Agricultural Phosphorus Loading Over the Last ~100 Years.

    Science.gov (United States)

    Vermaire, J. C.; Taranu, Z. E.; MacDonald, G. K.; Velghe, K.; Bennett, E.; Gregory-Eaves, I.

    2015-12-01

    Rapid changes in ecosystem states have occurred naturally throughout Earth's history. However, environmental changes that have taken place since the start of the Anthropocene may be destabilizing ecosystems and increasing the frequency of regime shifts in response to abrupt changes in external drivers or local intrinsic dynamics. To evaluate the relative influence of these forcers and improve our understanding of the impact of future change, we examined the effects of historical catchment phosphorus loading associated with agricultural land use on lake ecosystems, and whether this caused a shift from a stable, clear-water, regime to a turbid, cyanobacteria-dominated, state. The sedimentary pigments, diatom, and zooplankton (Cladocera) records from a currently clear-water shallow lake (Roxton Pond) and a turbid-water shallow lake (Petit lac Saint-François; PSF) were examined to determine if a cyanobacteria associated pigment (i.e. echinenone) showed an abrupt non-linear response to continued historical phosphorus load index (determined by phosphorus budget) over the last ~100 years. While PSF lake is presently in the turbid-water state, pigment and diatom analyses indicated that both lakes were once in the clear-water state, and that non-linear increases in catchment phosphorus balance resulted in an abrupt transition to cyanobacteria dominated states in each record. These results show that phosphorus loading has resulted in state shifts in shallow lake ecosystems that has been recorded across multiple paleolimnological indicators preserved in the sedimentary record.

  4. Spatially-Distributed Cost-Effectiveness Analysis Framework to Control Phosphorus from Agricultural Diffuse Pollution.

    Directory of Open Access Journals (Sweden)

    Runzhe Geng

    Full Text Available Best management practices (BMPs for agricultural diffuse pollution control are implemented at the field or small-watershed scale. However, the benefits of BMP implementation on receiving water quality at multiple spatial is an ongoing challenge. In this paper, we introduce an integrated approach that combines risk assessment (i.e., Phosphorus (P index, model simulation techniques (Hydrological Simulation Program-FORTRAN, and a BMP placement tool at various scales to identify the optimal location for implementing multiple BMPs and estimate BMP effectiveness after implementation. A statistically significant decrease in nutrient discharge from watersheds is proposed to evaluate the effectiveness of BMPs, strategically targeted within watersheds. Specifically, we estimate two types of cost-effectiveness curves (total pollution reduction and proportion of watersheds improved for four allocation approaches. Selection of a ''best approach" depends on the relative importance of the two types of effectiveness, which involves a value judgment based on the random/aggregated degree of BMP distribution among and within sub-watersheds. A statistical optimization framework is developed and evaluated in Chaohe River Watershed located in the northern mountain area of Beijing. Results show that BMP implementation significantly (p >0.001 decrease P loss from the watershed. Remedial strategies where BMPs were targeted to areas of high risk of P loss, deceased P loads compared with strategies where BMPs were randomly located across watersheds. Sensitivity analysis indicated that aggregated BMP placement in particular watershed is the most cost-effective scenario to decrease P loss. The optimization approach outlined in this paper is a spatially hierarchical method for targeting nonpoint source controls across a range of scales from field to farm, to watersheds, to regions. Further, model estimates showed targeting at multiple scales is necessary to optimize program

  5. Downstream approaches to phosphorus management in agricultural landscapes: regional applicability and use.

    Science.gov (United States)

    Kröger, R; Dunne, E J; Novak, J; King, K W; McLellan, E; Smith, D R; Strock, J; Boomer, K; Tomer, M; Noe, G B

    2013-01-01

    This review provides a critical overview of conservation practices that are aimed at improving water quality by retaining phosphorus (P) downstream of runoff genesis. The review is structured around specific downstream practices that are prevalent in various parts of the United States. Specific practices that we discuss include the use of controlled drainage, chemical treatment of waters and soils, receiving ditch management, and wetlands. The review also focuses on the specific hydrology and biogeochemistry associated with each of those practices. The practices are structured sequentially along flowpaths as you move through the landscape, from the edge-of-field, to adjacent aquatic systems, and ultimately to downstream P retention. Often practices are region specific based on geology, cropping practices, and specific P related problems and thus require a right practice, and right place mentality to management. Each practice has fundamental P transport and retention processes by systems that can be optimized by management with the goal of reducing downstream P loading after P has left agricultural fields. The management of P requires a system-wide assessment of the stability of P in different biogeochemical forms (particulate vs. dissolved, organic vs. inorganic), in different storage pools (soil, sediment, streams etc.), and under varying biogeochemical and hydrological conditions that act to convert P from one form to another and promote its retention in or transport out of different landscape components. There is significant potential of hierarchically placing practices in the agricultural landscape and enhancing the associated P mitigation. But an understanding is needed of short- and long-term P retention mechanisms within a certain practice and incorporating maintenance schedules if necessary to improve P retention times and minimize exceeding retention capacity.

  6. Topsoil and subsoil properties influence phosphorus leaching from four agricultural soils.

    Science.gov (United States)

    Andersson, Helena; Bergström, Lars; Djodjic, Faruk; Ulén, Barbro; Kirchmann, Holger

    2013-01-01

    Eutrophication, a major problem in many fresh and brackish waters, is largely caused by nonpoint-source pollution by P from agricultural soils. This lysimeter study examined the influence of P content, physical properties, and sorption characteristics in topsoil and subsoil on P leaching measured during 21 mo in 1-m-long, undisturbed soil columns of two clay and two sandy soils. Total P losses during the period varied between 0.65 and 7.40 kg ha. Dissolved reactive P was the dominant form in leachate from the sandy soils and one clay soil, varying from 48 to 76%. Particulate P dominated in leachate from the other clay soil, where low pH (5.2) in the subsoil decreased aggregate stability and thereby probably increased the dispersion of clay particles. Phosphorus leaching was small from soils with high P sorption index (PSI) and low P saturation (soil with low sorption capacity and high P saturation (>35% of PSI) in the profile. High sorption capacity in the subsoil was more important for P leaching in sandy soils than in clay soils with macropore flow, where the effect of high sorption capacity was reduced due to less interaction between percolating water and the soil matrix. The results suggest that P leaching is greatly affected by subsoil properties and that topsoil studies, which dominate current research, are insufficient for assessing P leaching in many soils. PMID:23673838

  7. Arbuscular mycorrhizal fungi in soil and roots respond differently to phosphorus inputs in an intensively managed calcareous agricultural soil.

    Science.gov (United States)

    Liu, Wei; Zhang, Yunlong; Jiang, Shanshan; Deng, Yan; Christie, Peter; Murray, Philip J; Li, Xiaolin; Zhang, Junling

    2016-01-01

    Understanding the diversity and community structure of arbuscular mycorrhizal fungi (AMF) is important for potentially optimizing their role in mining phosphorus (P) in agricultural ecosystems. Here, we conduct a comprehensive study to investigate the vertical distribution of AMF in a calcareous field and their temporal structure in maize-roots with fertilizer P application over a three-year period. The results showed that soil available-P response to P fertilization but maize yields did not. Phosphorus fertilization had no-significant effect on richness of AMF except at greater soil-depths. High P-supply reduced root colonization while optimum-P tended to increase colonization and fungal richness on all sampling occasions. Crop phenology might override P-supply in determining the community composition of active root inhabiting fungi. Significant differences in the community structure of soil AMF were observed between the controls and P treatments in surface soil and the community shift was attributable mainly to available-P, N/P and pH. Vertical distribution was related mainly to soil electrical conductivity and Na content. Our results indicate that the structure of AMF community assemblages is correlated with P fertilization, soil depth and crop phenology. Importantly, phosphorus management must be integrated with other agricultural-practices to ensure the sustainability of agricultural production in salinized soils. PMID:27102357

  8. Adsorption Control Performance of Phosphorus Removal from Agricultural Non-Point Source Pollution by Nano-Aperture Lanthanum-modified Active Alumina

    OpenAIRE

    Hong-Bing Luo; Fei Li; Hao Lv; Ying-Mei Zeng; Ke Zhang; Bo Huang

    2012-01-01

    It is great significance to control the phosphorus pollution from agricultural non-point source pollution. In this study, adsorption control performance of phosphorus removal from agricultural non-point source pollution by manual nano-aperture Lanthanum-modified active alumina was a great inspiring from urban-rural-integration-area. About 10 to 30 nanometers aperture on granule surfaces from the active alumina (&gamma-Al2 O3 which average sphere diameters is 3 mm, was formed after modificatio...

  9. Feeding the Corn Belt: Opportunities for phosphorus recycling in U.S. agriculture.

    Science.gov (United States)

    Metson, Geneviève S; MacDonald, Graham K; Haberman, Daniel; Nesme, Thomas; Bennett, Elena M

    2016-01-15

    The supply of phosphorus (P) is a critical concern for food security. Concentrated mineral P deposits have been the source of almost all new P entering the biosphere. However, this resource is often used inefficiently, raising concerns about both nutrient pollution and future access to fertilizers. One solution to both of these problems is to enhance our ability to capture and recycle P from waste streams. However, the efficacy of doing this has not been rigorously explored. Here, we examine the potential for recycling major P sources in the United States to supply the necessary P for domestic corn (maize) production. Using 2002 population and agricultural census data, we examine the distribution of three key recyclable P sources (human food waste, human excreta, and animal manure) and P demand from grain and silage corn across the country to determine the distance P would need to be transported from sources to replenish P removed from soils in harvested corn plants. We find that domestic recyclable P sources, predominantly from animal manures, could meet national corn production P demands with no additional fertilizer inputs. In fact, only 37% of U.S. sources of recyclable P would be required to meet all P demand from U.S. corn harvested annually. Seventy-four percent of corn P demand could be met by recyclable P sources in the same county. Surplus recyclable P sources within-counties would then need to travel on average 302 km to meet the largest demand in and around the center of the 'Corn Belt' region where ~50% of national corn P demand is located. We find that distances between recyclable sources and crop demands are surprisingly short for most of the country, and that this recycling potential is mostly related to manure. This information can help direct where recycling efforts should be most-effectively directed. PMID:26453407

  10. Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge

    Science.gov (United States)

    Sibrell, Philip L.; Montgomery, Gary A.; Ritenour, Kelsey L.; Tucker, Travis W.

    2009-01-01

    Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A??cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of acid mine drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that acid mine drainage sludges - hitherto thought of as undesirable wastes - can be used to remove phosphorus from wastewater, thus offsetting a portion of acid mine drainage treatment costs while at the same time improving water quality in sensitive watersheds.

  11. Iron coated sand/glauconite filters for phosphorus removal from artificially drained agricultural fields

    Science.gov (United States)

    Vandermoere, Stany; De Neve, Stefaan

    2016-04-01

    Flanders (Belgium) is confronted with reactive phosphorus concentrations in streams and lakes which are three to four times higher than the 0.1 ppm P limit set by the Water Framework Directive. Much of the excessive P input in surface waters is derived from agriculture. Direct P input from artificially drained fields (short-circuiting the buffering capacity of the subsoil) is suspected to be one of the major sources. We aim to develop simple and cheap filters that can be directly installed in the field to reduce P concentration from the drain water. Here we report on the performance of such filters tested at lab scale. As starting materials for the P filter, iron coated sand and acid pre-treated glauconite were used. These materials, both rich in Fe, were mixed in ratios of 75/25, 65/35, 50/50 and 0/100 (iron coated sand/glauconite ratio based on weight basis) and filled in plastic tubes. A screening experiment using the constant head method with a 0.01 M CaCl2 solution containing 1 ppm P showed that all four types of mixtures reduced the P concentration in the outflowing water to almost zero, and that the 75/25, 65/35 and 0/100 mixtures had a sufficiently large hydraulic conductivity of 0.9 to 6.0 cm/min, while the hydraulic conductivity of the 50/50 mixture was too low (plastic tubes as in the first experiment. Subsequently a 0.01 M CaCl2 solution containing 1 ppm P was passed through the filters over several days, in amounts equivalent to half of the yearly water volume passing through the drains. This experiment firstly showed that in all cases the hydraulic conductivity fluctuated strongly: it decreased from 4.0-6.0 cm/min to 2.0-1.5 cm/min for the 75/25 filter, and to values conductivity of the filter materials.

  12. Iron coated sand/glauconite filters for phosphorus removal from artificially drained agricultural fields

    Science.gov (United States)

    Vandermoere, Stany; De Neve, Stefaan

    2016-04-01

    Flanders (Belgium) is confronted with reactive phosphorus concentrations in streams and lakes which are three to four times higher than the 0.1 ppm P limit set by the Water Framework Directive. Much of the excessive P input in surface waters is derived from agriculture. Direct P input from artificially drained fields (short-circuiting the buffering capacity of the subsoil) is suspected to be one of the major sources. We aim to develop simple and cheap filters that can be directly installed in the field to reduce P concentration from the drain water. Here we report on the performance of such filters tested at lab scale. As starting materials for the P filter, iron coated sand and acid pre-treated glauconite were used. These materials, both rich in Fe, were mixed in ratios of 75/25, 65/35, 50/50 and 0/100 (iron coated sand/glauconite ratio based on weight basis) and filled in plastic tubes. A screening experiment using the constant head method with a 0.01 M CaCl2 solution containing 1 ppm P showed that all four types of mixtures reduced the P concentration in the outflowing water to almost zero, and that the 75/25, 65/35 and 0/100 mixtures had a sufficiently large hydraulic conductivity of 0.9 to 6.0 cm/min, while the hydraulic conductivity of the 50/50 mixture was too low (solution containing 1 ppm P was passed through the filters over several days, in amounts equivalent to half of the yearly water volume passing through the drains. This experiment firstly showed that in all cases the hydraulic conductivity fluctuated strongly: it decreased from 4.0-6.0 cm/min to 2.0-1.5 cm/min for the 75/25 filter, and to values < 0.4 cm/min for the 65/35 filter, whereas it increased from 0.8 to 1.4 cm/min for the 0/100 filter. Secondly, we observed a decrease in the P removal efficiency with time on each day for all filters: from 90% removal to 80% removal for the 75/25 and 65/35 filters, while for the 0/100 filter the P removal almost reduced to 0%. Based on these results the 75

  13. Factors controlling phosphorus export from agricultural/forest and residential systems to rivers in eastern China, 1980-2011

    Science.gov (United States)

    Chen, Dingjiang; Hu, Minpeng; Wang, Jiahui; Guo, Yi; Dahlgren, Randy A.

    2016-02-01

    This study quantified long-term response of riverine total phosphorus (TP) export to changes in land-use, climate, and net anthropogenic phosphorus inputs to agricultural/forest (NAPIAF) and residential (NAPIR) systems for the upper Jiaojiang watershed in eastern China. Annual NAPIAF rose by 73% in 1980-1999 followed by a 41% decline in 2000-2011, while NAPIR continuously increased by 122% over the 1980-2011 period. Land-use showed a 63% increase in developed land area (D%) and a 91% increase in use of efficient drainage systems on agricultural land area (AD%) over the study period. Although no significant trends were observed in annual river discharge or precipitation, the annual number of storm events rose by 90% along with a 34% increase in the coefficient of variation of daily rainfall. In response to changes of NAPIAF, NAPIR, land-use and precipitation patterns, riverine TP flux increased 16.0-fold over the 32-year record. Phosphorus export via erosion and leaching was the dominant pathway for P delivery to rivers. An empirical model incorporating annual NAPIAF, NAPIR, precipitation, D%, and AD% was developed (R2 = 0.96) for apportioning riverine TP sources and predicting annual riverine TP fluxes. The model estimated that NAPIAF, NAPIR and legacy P sources contributed 19-56%, 16-67% and 13-32% of annual riverine TP flux in 1980-2011, respectively. Compared to reduction of NAPIAF, reduction of NAPIR was predicted to have a greater immediate impact on decreasing riverine TP fluxes. Changes in anthropogenic P input sources (NAPIAF vs. NAPIR), land-use, and precipitation patterns as well as the legacy P source can amplify P export from landscapes to rivers and should be considered in developing P management strategies to reduce riverine P fluxes.

  14. Future supply of phosphorus in agriculture and the need to maximise efficiency of use and reuse

    NARCIS (Netherlands)

    Rosemarin, A.; Schroder, J.J.; Dagerskog, L.; Cordell, D.; Smit, A.L.

    2011-01-01

    Commercially viable reserves of rock phosphate are limited and only a few countries are significant producers. China and the US will play a much smaller role within 50 years time and the bulk of the world's mined phosphorus will come from Morocco. A conservative estimate of longevity of the resource

  15. Improved phosphorus use efficiency in agriculture: A key requirement for its sustainable use

    NARCIS (Netherlands)

    Schroder, J.J.; Smit, A.L.; Cordell, D.; Rosemarin, A.

    2011-01-01

    Mineral phosphorus (P) fertilizers processed from fossil reserves have enhanced food production over the past 50 years and, hence, the welfare of billions of people. Fertilizer P has, however, not only been used to lift the fertility level of formerly poor soils, but also allowed people to neglect t

  16. Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

    Science.gov (United States)

    Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

    2016-05-01

    The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field.

  17. Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

    Science.gov (United States)

    Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

    2016-05-01

    The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field. PMID:26901743

  18. Adsorption Control Performance of Phosphorus Removal from Agricultural Non-Point Source Pollution by Nano-Aperture Lanthanum-modified Active Alumina

    Directory of Open Access Journals (Sweden)

    Hong-Bing Luo

    2012-12-01

    Full Text Available It is great significance to control the phosphorus pollution from agricultural non-point source pollution. In this study, adsorption control performance of phosphorus removal from agricultural non-point source pollution by manual nano-aperture Lanthanum-modified active alumina was a great inspiring from urban-rural-integration-area. About 10 to 30 nanometers aperture on granule surfaces from the active alumina (&gamma-Al2 O3 which average sphere diameters is 3 mm, was formed after modification from Lanthanum (III chloride. Results show that the adsorption performance of phosphorus removal by using nano-aperture Lanthanum-modified active alumina was much higher percent 50% than active alumina under the optimum condition of pH (pH = 4, adsorption time (12 h and adsorption dosage of Lanthanum-modified active alumina (0.2 g/50 mL. The adsorption performance of phosphorus removal by nano-aperture Lanthanum-modified active alumina can reach the percentage of 96 from water samples in agricultural non-point source pollution. The adsorption kinetic accorded with the Pseudo-Second-order Kinetic Equations (R2 = 0.9955. The isothermal adsorption property was described by the Langmuir Equation (R2 = 0.9982 which the biggest adsorption capacity was 0.257 mg/g. The average removal efficiency of phosphorus from general farmland, corn field, paddy field, vegetable land was above 92%. It is very evident that the nano-aperture Lanthanum-modified active alumina will be a promising material for phosphorus removal control from agricultural non-point source pollution.

  19. Evaluation of phosphorus and nitrogen balances as an indicator for the impact of agriculture on environment a comparison of case studies from Poland and the Mississippi US

    Science.gov (United States)

    The objective of the research was to quantify the changes of nitrogen (N) and phosphorus (P) balances in Poland and Mississippi (MS). Nutrient balances were calculated as difference between input and output in the agricultural system according to Organisation for Economic Cooperation and Development...

  20. Reducing future non-point source sediment and phosphorus loading under intensifying agricultural production in the Ethiopian highlands

    Science.gov (United States)

    Mogus, Mamaru; Schmitter, Petra; Tilahun, Seifu; Steenhuise, Tammo

    2016-04-01

    Intensification of agriculture will bring along non-point source pollution in the Ethiopian highlands resulting in eutrophication of lakes. The first signs of eutrophication have been observed already in Lake Tana. The lake it supports the lives of millions in the surrounding through fishing, tourism, transportation and hydropower.Presently, information on non-point source pollution is lacking in the Ethiopian highlands. There are few studies carried out in the highlands on the extent and the source areas of pollution, and models are not available for predicting sediment and phosphorus loading other than those developed for temperate climates. The objective of this chapter is to review existing non-point source studies, report on our findings of sediment and phosphorus sources that are related the non-point source pollution of Lake Tana and to present a non-point source model for the Ethiopian highland based on the Parameter Efficient Semi-distributed Watershed Hydrology Model (PED-WHM).In our research we have found that the saturation excess runoff from valley bottoms and from degraded lands are prevalent in the Ethiopia highlands. The periodically runoff source areas are also the sources for the non-point source pollution and by concentrating best management practices in these source areas we expect that we can reduce pollution without affecting the profitability of the existing farms. The water balance component of the non-point source model has been performing well in predicting both the discharge and the location of the runoff source areas. Sediment and phosphorus prediction models have been developed and are currently being tested for the 7km2Awramba watershed and the 1350 km2Gumara basin. Initial results indicate that 11.2 ton/ha/year sediment load and an accumulation rate of 17.3 mg/kg/year of dissolved phosphorus from Gumara watershed joining the lake. By developing best management practices at this time before non-point source pollution is rampant and

  1. Effects of lakes and reservoirs on annual river nitrogen, phosphorus, and sediment export in agricultural and forested landscapes

    Science.gov (United States)

    Powers, Steve M.; Robertson, Dale M.; Stanley, Emily H.

    2014-01-01

    Recently, effects of lakes and reservoirs on river nutrient export have been incorporated into landscape biogeochemical models. Because annual export varies with precipitation, there is a need to examine the biogeochemical role of lakes and reservoirs over time frames that incorporate interannual variability in precipitation. We examined long-term (~20 years) time series of river export (annual mass yield, Y, and flow-weighted mean annual concentration, C) for total nitrogen (TN), total phosphorus (TP), and total suspended sediment (TSS) from 54 catchments in Wisconsin, USA. Catchments were classified as small agricultural, large agricultural, and forested by use of a cluster analysis, and these varied in lentic coverage (percentage of catchment lake or reservoir water that was connected to river network). Mean annual export and interannual variability (CV) of export (for both Y and C) were higher in agricultural catchments relative to forested catchments for TP, TN, and TSS. In both agricultural and forested settings, mean and maximum annual TN yields were lower in the presence of lakes and reservoirs, suggesting lentic denitrification or N burial. There was also evidence of long-term lentic TP and TSS retention, especially when viewed in terms of maximum annual yield, suggesting sedimentation during high loading years. Lentic catchments had lower interannual variability in export. For TP and TSS, interannual variability in mass yield was often >50% higher than interannual variability in water yield, whereas TN variability more closely followed water (discharge) variability. Our results indicate that long-term mass export through rivers depends on interacting terrestrial, aquatic, and meteorological factors in which the presence of lakes and reservoirs can reduce the magnitude of export, stabilize interannual variability in export, as well as introduce export time lags.

  2. Key role of China and its agriculture in global sustainable phosphorus management

    International Nuclear Information System (INIS)

    Growing global demand for food leads to increased pressure on phosphorus (P), a finite and dwindling resource. China is the largest producer and consumer of P fertilizer in the world. A mass balance analysis of historical P use on China’s arable land shows that P input substantially exceeds crop P uptake leading to the accumulation of residual soil P. A Dynamic P Pool Simulator (DPPS) model is applied to estimate future P demand in China’s arable land. Our simulations show that more sustainable use of P accounting for the residual P can save ca. 20% of the P fertilizer needed until 2050 in China relative to the Rio + 20 Trend scenario. This saving would be equivalent to half of the P required in Africa or sufficient for Western Europe to achieve target crop P uptake in 2050. (letters)

  3. Sensitivity Analysis of the Agricultural Policy/Environmental eXtender (APEX) for Phosphorus Loads in Tile-Drained Landscapes.

    Science.gov (United States)

    Ford, W; King, K; Williams, M; Williams, J; Fausey, N

    2015-07-01

    Numerical modeling is an economical and feasible approach for quantifying the effects of best management practices on dissolved reactive phosphorus (DRP) loadings from agricultural fields. However, tools that simulate both surface and subsurface DRP pathways are limited and have not been robustly evaluated in tile-drained landscapes. The objectives of this study were to test the ability of the Agricultural Policy/Environmental eXtender (APEX), a widely used field-scale model, to simulate surface and tile P loadings over management, hydrologic, biologic, tile, and soil gradients and to better understand the behavior of P delivery at the edge-of-field in tile-drained midwestern landscapes. To do this, a global, variance-based sensitivity analysis was performed, and model outputs were compared with measured P loads obtained from 14 surface and subsurface edge-of-field sites across central and northwestern Ohio. Results of the sensitivity analysis showed that response variables for DRP were highly sensitive to coupled interactions between presumed important parameters, suggesting nonlinearity of DRP delivery at the edge-of-field. Comparison of model results to edge-of-field data showcased the ability of APEX to simulate surface and subsurface runoff and the associated DRP loading at monthly to annual timescales; however, some high DRP concentrations and fluxes were not reflected in the model, suggesting the presence of preferential flow. Results from this study provide new insights into baseline tile DRP loadings that exceed thresholds for algal proliferation. Further, negative feedbacks between surface and subsurface DRP delivery suggest caution is needed when implementing DRP-based best management practices designed for a specific flow pathway. PMID:26437091

  4. Turnover and losses of phosphorus in Swedish agricultural soils: long-term changes, leaching trends, and mitigation measures.

    Science.gov (United States)

    Bergström, Lars; Kirchmann, Holger; Djodjic, Faruk; Kyllmar, Katarina; Ulén, Barbro; Liu, Jian; Andersson, Helena; Aronsson, Helena; Börjesson, Gunnar; Kynkäänniemi, Pia; Svanbäck, Annika; Villa, Ana

    2015-03-01

    Transport of phosphorus (P) from agricultural fields to water bodies deteriorates water quality and causes eutrophication. To reduce P losses and optimize P use efficiency by crops, better knowledge is needed of P turnover in soil and the efficiency of best management practices (BMPs). In this review, we examined these issues using results from 10 Swedish long-term soil fertility trials and various studies on subsurface losses of P. The fertility trials are more than 50 years old and consist of two cropping systems with farmyard manure and mineral fertilizer. One major finding was that replacement of P removed by crops with fertilizer P was not sufficient to maintain soil P concentrations, determined with acid ammonium lactate extraction. The BMPs for reducing P leaching losses reviewed here included catch crops, constructed wetlands, structure liming of clay soils, and various manure application strategies. None of the eight catch crops tested reduced P leaching significantly, whereas total P loads were reduced by 36% by wetland installation, by 39 to 55% by structure liming (tested at two sites), and by 50% by incorporation of pig slurry into a clay soil instead of surface application. Trend analysis of P monitoring data since the 1980s for a number of small Swedish catchments in which various BMPs have been implemented showed no clear pattern, and both upward and downward trends were observed. However, other factors, such as weather conditions and soil type, have profound effects on P losses, which can mask the effects of BMPs. PMID:26023970

  5. Regulation og non-point phosphorus emissions from the agricultural sector by use of economic incentives

    DEFF Research Database (Denmark)

    Hansen, Line Block

    of economic incentives applied in the agricultural sector on 1) P-surplus application rates at the field level; 2) the accumulation of P in the soil; 3) the level of risk of P losses to the aquatic ecosystem; and 4) farm economics when analysed using a profit maximization approach. The thesis consists of four...... and identifies the most important parameters to include in a dynamic model where farm profit is maximized over time whilst taking soil-P dynamics into account. The paper focuses on heterogeneity of farm type and how these farmers utilize the soil-P stock and apply P fertilizers. The second paper completes...... profit maximization model is developed for an area in the catchment area of Odense Fjord, Denmark. The area covers 3,993 hectares and is cultivated by 258 arable, cattle and pig farmers. The paper investigates two different general incentives for reducing soil P losses: a tax on mineral-fertilizer P...

  6. Suspended Sediment and Phosphorus Removal in a Woodchip Filter System Treating Agricultural Wash Water.

    Science.gov (United States)

    Choudhury, Tahina; Robertson, Will Dean; Finnigan, Darryl S

    2016-05-01

    Woodchip filters have received attention in recent years for their ability to sustain denitrification activity across multiyear time frames. However, in some freshwater aquatic ecosystems, P rather than N is the nutrient considered most responsible for eutrophication. Previous studies have indicated that woodchip filters have limited ability to remove dissolved P, but in agricultural terrain, P export in watercourses is often dominated by particulate P (PP). Woodchip media, because of their high porosity and permeability and the surface roughness of the particles, could be effective for PP removal. In this study, we tested a woodchip filter for its ability to remove suspended sediment and associated PP at a farm in southern Ontario, Canada, where vegetable wash water with extremely high total suspended solids (TSS) was generated. The treatment system consisted of a 12.3-m concrete sedimentation tank and a slightly larger woodchip filter (16.1 m) installed in a subsurface trench. During 7 mo of full-scale operation, treating 10.8 m d, the filter system removed 71% of influent total P (TP) averaging 8.8 mg L and 99% of TSS averaging 5800 mg L, with most of the removal occurring in the tank and a lesser amount (6-16%) occurring in the woodchip filter. Almost all of the TP removal was associated with PP (91% removal) because dissolved P, averaging 1.5 mg L in the wash water, was little changed. Woodchip filters, when coupled with a solids settling tank, have the potential to provide high-capacity, low-maintenance treatment of suspended solids and associated particulate P in turbid waters. PMID:27136144

  7. Effect of variable annual precipitation and nutrient input on nitrogen and phosphorus transport from two Midwestern agricultural watersheds

    Science.gov (United States)

    Kalkhoff, Stephen J.; Hubbard, Laura E.; Tomer, Mark D.; James, D.E.

    2016-01-01

    Precipitation patterns and nutrient inputs affect transport of nitrate (NO3-N) and phosphorus (TP) from Midwest watersheds. Nutrient concentrations and yields from two subsurface-drained watersheds, the Little Cobb River (LCR) in southern Minnesota and the South Fork Iowa River (SFIR) in northern Iowa, were evaluated during 1996–2007 to document relative differences in timings and amounts of nutrients transported. Both watersheds are located in the prairie pothole region, but the SFIR exhibits a longer growing season and more livestock production. The SFIR yielded significantly more NO3-N than the LCR watershed (31.2 versus 21.3 kg NO3-N ha− 1 y− 1). The SFIR watershed also yielded more TP than the LCR watershed (1.13 versus 0.51 kg TP ha− 1 yr− 1), despite greater TP concentrations in the LCR. About 65% of NO3-N and 50% of TP loads were transported during April–June, and < 20% of the annual loads were transported later in the growing season from July–September. Monthly NO3-N and TP loads peaked in April from the LCR but peaked in June from the SFIR; this difference was attributed to greater snowmelt runoff in the LCR. The annual NO3-N yield increased with increasing annual runoff at a similar rate in both watersheds, but the LCR watershed yielded less annual NO3-N than the SFIR for a similar annual runoff. These two watersheds are within 150 km of one another and have similar dominant agricultural systems, but differences in climate and cropping inputs affected amounts and timing of nutrient transport.

  8. Influence of particulates on phosphorus loading exported from farm drainage during a storm event in the Everglades Agricultural Area

    Science.gov (United States)

    Bhadha, J. H.; Lang, T. A.; Daroub, S. H.

    2015-12-01

    The purpose of this study was to evaluate the influence of particulates on P loading captured during a single storm event. The Everglades Agricultural Area of Florida comprises 280,000 hectares of organic soil farmland artificially drained by ditches, canals and pumps. Phosphorus (P)-enriched suspended particulates in canals are susceptible to transport and can contribute significantly to the overall P loads in drainage water. A settling tank experiment was conducted to capture particulates during tropical storm Isaac in 2012 from three farms approximately 2.4 to 3.6 km2 in size. Farm canal discharge water was collected in a series of two 200 liter settling tanks over a seven-day drainage period, during tropical storm Isaac. Water from the settling tanks was siphoned through Imhoff settling cones, where the particulates were allowed to settle and collected for P-fractionation analyses, and compared to intact sediment cores collected from the bottom of the canals. The discharged particulates contained higher organic matter content (OM), total P, and labile P fractions compared to the canal bottom sediments. Based on the equilibrium P concentrations, surface sediments behave as a source of P to the water column. A seven-day continuous drainage event exported 4.7 to 11.1 metric tons of suspended solids per farm, corresponding to 32 to 63 kg of particulate P being lost to downstream ecosystems. Drainage associated to a single seven-day storm event exported up to 61% of the total annual farm P load. It is evident from this study that short-term, high-intensity storm events can skew annual P loads due to the export of significantly higher particulate matter from farm canals. Exported particulates rich in P can provide a supplemental source of nutrients if captured and replenished back into the farmlands, as a sustainable farming practice.

  9. The need for an improved risk index for phosphorus losses to water from tile-drained agricultural land

    Science.gov (United States)

    Ulén, Barbro; Djodjic, Faruk; Etana, Araso; Johansson, Göran; Lindström, Jan

    2011-03-01

    SummaryA refined version of a conditional phosphorus risk index (PRI) for P losses to waters was developed based on monitoring and analyses of PRI factors from an agricultural catchment in Sweden. The catchment has a hummocky landscape of heavy glacial till overlying moraine and an overall balanced soil P level. Single P source factors and combinations of factors were tested and discussed together with water movement and water management factors important for catchments dominated by drained clay soils. An empirical relationship was established (Pearson correlation coefficient 0.861, p ammonium lactate. Differing relationships were found for a field that had not received any manure in the last 15 years and a field that had received chicken litter very recently. In addition, a general relationship (Pearson correlation coefficient 0.839, p lactate extract (DPS-AL). One exception was a single field, representing 7% of agricultural land in the catchment, that had been treated with glyphosate shortly before soil sampling. Saturated hydraulic conductivity (SHC) in heavy clay in contact with the moraine base (at 1 m depth) was on average 0.06 m day -1. In clay not in contact with moraine, SHC was significantly lower (mean 0.007 m day -1). A reduction in the present tile drain spacing (from 14-16 m to 11 m) is theoretically required to maintain satisfactory water discharge and groundwater level. Up to 10% of the arable land was estimated to be a potential source area for P, based on different indices. Parts of a few fields close to farm buildings (1% of total arable land) were identified as essential P source areas, with high DPS-AL values and low PSI-CaCl 2 values throughout the soil profile. A further 2% of arable land was identified as potential important transport areas, based on visible surface water rills or frequent water-ponded conditions. Fields comprising 10% of the total arable land in the catchment should be re-drained in the near future to improve water

  10. Contrasting nitrogen and phosphorus export regimes in agricultural streams of the Upper Mississippi and Great Lakes Basins

    Science.gov (United States)

    Powers, S. M.; Robertson, D.; Tank, J.

    2012-12-01

    Transport of excess fertilizer runoff from agricultural lands to adjacent water bodies can fluctuate substantially among years. Studies of large basins (e.g., Mississippi R.) have shown that inter-annual variation in river nutrient export is strongly related to annual precipitation or discharge. However, other environmental factors affect this variation, which should also differ among constituents. We used 20 year records of annual nutrient yield (Y), water yield (Q), and mean flow-weighted annual concentration (C=Y/Q) to characterize total nitrogen (TN) and total phosphorus (TP) export regimes of small and intermediate sized catchments (n>200) in the Upper Mississippi and Great Lakes Basins. We examined two main criteria: slope of the C~Q relationship (slope), and strength of the C~Q relationship (r). We chose qualitative thresholds for these criteria (slope 1, concentrating; r weak Y~Q relationship; r >0.5 strong Y~Q relationship) which bound distinct quadrants (classes) in export regime space. For example, catchments with slope>1 and r>0.5 (export regime class: strongly concentrating) are prone to episodic transport of TN or TP which is tightly linked to Q. We found that all four export regime classes were represented by streams in the study region. For both TN and TP, most sites had positive, significant slope, including several high values (r =2-10) which indicate a tendency for episodic transport. slope ≤0 and non-significant slope were more common for TN than for TP. Future work will examine effects of landscape factors on Y, including those associated with increased water residence time in stream networks (e.g., surface water coverage, wetland coverage) as well as decreased water residence time (e.g., catchment slope, crop coverage, presence of tile drainage) which may dampen or amplify Y variability. Quantifying linkages between landscape characteristics and stream export regime could strengthen our ability to predict the dynamics of manure and

  11. Spatial and temporal variations in non-point source losses of nitrogen and phosphorus in a small agricultural catchment in the Three Gorges Region.

    Science.gov (United States)

    Chen, Chenglong; Gao, Ming; Xie, Deti; Ni, Jiupai

    2016-04-01

    Losses of agricultural pollutants from small catchments are a major issue for water quality in the Three Gorges Region. Solutions are urgently needed. However, before pollutant losses can be controlled, information about spatial and temporal variations in pollutant losses is needed. The study was carried out in the Wangjiagou catchment, a small agricultural catchment in Fuling District, Chongqing, and the data about non-point source losses of nitrogen and phosphorus was collected here. Water samples were collected daily by an automatic water sampler at the outlets of two subcatchments from 2012 to 2014. Also, samples of surface runoff from 28 sampling sites distributed through the subcatchments were collected during 12 rainfall events in 2014. A range of water quality variables were analyzed for all samples and were used to demonstrate the variation in non-point losses of nitrogen and phosphorus over a range of temporal and spatial scales and in different types of rainfall in the catchment. Results showed that there was a significant linear correlation between the mass concentrations of total nitrogen (TN) and nitrate (NO3-N) in surface runoff and that the relationship was maintained with changes in time. Concentrations of TN and NO3-N peaked after fertilizer was applied to crops in spring and autumn; concentrations decreased rapidly after the peak values in spring but declined slowly in autumn. N and P concentrations fluctuated more and showed a greater degree of dispersion during the spring crop cultivation period than those in autumn. Concentrations of TN and NO3-N in surface runoff were significantly and positively correlated with the proportion of the area that was planted with corn and mustard tubers, but were negatively correlated with the proportion of the area taken up with rice and mulberry plantations. The average concentrations of TN and NO3-N in surface runoff reached the highest level from the sampling points at the bottom of the land used for corn

  12. Effects of agricultural practices on soil and microbial biomass carbon, nitrogen and phosphorus content: a preliminary case study

    OpenAIRE

    F. Amaral; M. Abelho

    2016-01-01

    In this study we assessed the C : N : P ratios in soil and soil microbial biomass subject to conventional farming and three different organic farming practices. The results showed that microbial biomass was P-limited in soils subject to conventional farming and to organic farming with alfalfa green manure. Organic farming with compost amendment showed the best results in terms of microbial biomass carbon, nitrogen and phosphorus (CNP).

  13. Phosphorus fractions in an agricultural chronosequence under tillage regimes in the Cerrado area in Goiás, Brazil

    Directory of Open Access Journals (Sweden)

    Roni Fernandes Guareschi

    2016-04-01

    Full Text Available The increase in the amount and quantity of soil organic matter (SOM, as well as the use of phosphorus-based fertilizers in the superficial soil layer in areas under tillage regimes (TR, may affect phosphorus (P dynamics in the soil. Therefore, the aims of the present work were as follows: to evaluate the inorganic and organic fractions of P and its lability levels (labile, moderately labile, and moderately resistant in a Distroferric Red Latosol under tillage regimes (TR 3, 15, and 20 years after implementation, and to compare them with those of areas of native Cerrado and pastures. We also focus on analyzing the correlations of the P fractions in these areas with other soil attributes, such as total carbon and nitrogen levels, light organic matter (LOM, chemical and physical granulometric fractions of the SOM, maximum phosphate adsorption capacity (MPAC, and the remaining phosphorus (Prem. In each of these areas, samples were collected from the 0.0-0.05 and 0.05-0.10 m soil layers. An entirely randomized experimental design was used. After TR implementation, the constant use of phosphorus-based fertilizers as well as the incremental addition of SOM resulted in an increase in the levels of labile, moderate labile, and moderately resistant organic and inorganic P, with a tendency for total P accumulation to be mostly in the inorganic, moderately labile form. The native Cerrado soil presented high levels of labile and moderately labile inorganic P. Pasture areas presented the lowest levels of labile organic and inorganic P, as well as moderately labile and moderately resistant organic P. By principal component analysis (PCA, it was possible to observe alterations in all soil attributes and P levels of the fractions analyzed.

  14. Soil acid phosphomonoesterase activity and phosphorus forms in ancient and post-agricultural black alder [Alnus glutinosa (L.) Gaertn.] woodlands

    OpenAIRE

    Anna Orczewska; Anna Piotrowska; Joanna Lemanowicz

    2012-01-01

    Black alder, an N-fixing tree is considered to accelerate the availability of phosphorus in soils due to the increased production of phosphatase enzymes, which are responsible for the P release from the litter. Acid phosphatase activity plays a pivotal role in organic P mineralization in forest soils and in making P available to plants. In order to check whether Alnus glutinosa stimulates acid phosphomonoesterase (PHACID) activity, we compared enzyme activities, total P concentration (PTOT), ...

  15. Prediction of dissolved reactive phosphorus losses from small agricultural catchments: calibration and validation of a parsimonious model

    Directory of Open Access Journals (Sweden)

    C. Hahn

    2013-10-01

    Full Text Available Eutrophication of surface waters due to diffuse phosphorus (P losses continues to be a severe water quality problem worldwide, causing the loss of ecosystem functions of the respective water bodies. Phosphorus in runoff often originates from a small fraction of a catchment only. Targeting mitigation measures to these critical source areas (CSAs is expected to be most efficient and cost-effective, but requires suitable tools. Here we investigated the capability of the parsimonious Rainfall-Runoff-Phosphorus (RRP model to identify CSAs in grassland-dominated catchments based on readily available soil and topographic data. After simultaneous calibration on runoff data from four small hilly catchments on the Swiss Plateau, the model was validated on a different catchment in the same region without further calibration. The RRP model adequately simulated the discharge and dissolved reactive P (DRP export from the validation catchment. Sensitivity analysis showed that the model predictions were robust with respect to the classification of soils into "poorly drained" and "well drained", based on the available soil map. Comparing spatial hydrological model predictions with field data from the validation catchment provided further evidence that the assumptions underlying the model are valid and that the model adequately accounts for the dominant P export processes in the target region. Thus, the parsimonious RRP model is a valuable tool that can be used to determine CSAs. Despite the considerable predictive uncertainty regarding the spatial extent of CSAs, the RRP can provide guidance for the implementation of mitigation measures. The model helps to identify those parts of a catchment where high DRP losses are expected or can be excluded with high confidence. Legacy P was predicted to be the dominant source for DRP losses and thus, in combination with hydrologic active areas, a high risk for water quality.

  16. Return of phosphorus in agricultural residues and urban sewage sludge to soil using biochar from low-temperature gasification as fertilizer product

    DEFF Research Database (Denmark)

    Müller-Stöver, Dorette Sophie; Jensen, Lars Stoumann; Grønlund, Mette;

    The return of residual products from bioenergy generation to soils is a step towards closing nutrient cycles, which is especially important for nutrients produced from non-renewable resources such as phosphorus (P). Low-temperature gasification is an innovative process efficiently generating energy...... from different biomass fuels, such as agricultural residues and waste streams, and at the same time producing a biochar product potentially valuable for soil amendment. In pot experiments, different residual products originating from low-temperature gasification were tested for their P-fertilizing...... potential with spring barley as a test crop. Biochar resulting from gasification of pure wheat straw showed the best P fertilizer value, however, because of the low P content, extremely high amounts had to be applied when crop P demand should be met, which came along with an over-fertilization of potassium...

  17. PSYCHIC A process-based model of phosphorus and sediment transfers within agricultural catchments. Part 2. A preliminary evaluation

    Science.gov (United States)

    Strömqvist, J.; Collins, A. L.; Davison, P. S.; Lord, E. I.

    2008-02-01

    SummaryThis paper describes the preliminary evaluation of the PSYCHIC catchment scale (Tier 1) model for predicting the mobilisation and delivery of phosphorus (P) and suspended sediment (SS) in the Hampshire Avon (1715 km 2) and Herefordshire Wye (4017 km 2) drainage basins, in the UK, using empirical data. Phosphorus and SS transfers to watercourses in the Wye were predicted to be greater than corresponding delivery in the Avon; SS, 249 vs 33 kg ha -1 yr -1; DP, 2.57 vs 1.26 kg ha -1 yr -1; PP, 2.20 vs 0.56 kg ha -1 yr -1. The spatial pattern of the predicted transfers was relatively uniform across the Wye drainage basin, whilst in the Avon, delivery to watercourses was largely confined to the river corridors and small areas of drained land. Statistical performance in relation to predicted exports of P and SS, using criteria for relative error (RE) and root mean square error (RMSE), reflected the potential shortcomings associated with using longer-term climate data for predicting shorter-term (2002-2004) catchment response and the need to refine calculations of point source contributions and to incorporate additional river basin processes such as channel bank erosion and in-stream geochemical processing. PSYCHIC is therefore best suited to characterising longer-term catchment response.

  18. Agriculture

    International Nuclear Information System (INIS)

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on agriculture describes how climate change will affect primary agriculture production in Canada with particular focus on potential adaptation options, and vulnerability of agriculture at the farm level. Agriculture is a vital part of the Canadian economy, although only 7 per cent of Canada's land mass is used for agricultural purposes due to the limitations of climate and soils. Most parts of Canada are expected to experience warmer conditions, longer frost-free seasons and increased evapotranspiration. The impacts of these changes on agriculture will vary depending on precipitation changes, soil conditions, and land use. Northern regions may benefit from longer farming seasons, but poor soil conditions will limit the northward expansion of agricultural crops. Some of the negative impacts associated with climate change on agriculture include increased droughts, changes in pest and pathogen outbreaks, and moisture stress. In general, it is expected that the positive and negative impacts of climate change would offset each other. 74 refs., 2 tabs., 1 fig

  19. Hydrologic controls on the export dynamics of dissolved and particulate phosphorus in a lowland, headwater agricultural catchment

    Science.gov (United States)

    Dupas, Rémi; Grimaldi, Catherine; Gruau, Gérard; Gascuel-Odoux, Chantal

    2014-05-01

    Phosphorus (P) availability controls eutrophication in freshwater ecosystems, since P is generally the limiting nutrient to algal development. The contribution of diffuse P emission to surface waters is significant in intensively livestock farmed catchments as a result of high application rates of P-rich animal waste and subsequent enrichment of soils. This study investigates the transport dynamics of particulate phosphorus (PP), suspended sediments (SS), and dissolved phosphorus (DP) with the aim of elucidating the relationship between PP and DP transport mechanisms and water dynamics in lowland, headwater catchments. The selected catchment (Kervidy-Naizin catchment, France) is particularly suitable for this purpose as it benefits of a 5 years, high-frequency monitoring of PP and DP concentrations at its outlet, including data recovered both during base flow and storm periods, with the monitoring of more than 50 storm flow events. The data analysis includes interpretation of concentration-discharge relationships at the annual time scale and on an event basis, seasonal analysis of flood characteristics and empirical modeling. Annual DP and PP concentration-discharge relationships of interflood samples display a hysteretic pattern, with higher concentrations during the autumn and spring periods, and progressive decrease during winter. No hysteretic pattern is visible for interflood SS concentration, which follows a classical C=a*Qb relationship. During floods, the dynamic of PP export is similar to that of SS during most of the events: the concentration peak occurs during the rising limb of the hydrogram (clockwise hysteresis), suggesting a source close to or within the stream. The amplitude and the hysteresis' loop size for SS and PP are a function of maximum discharge and rate of change in discharge. On the contrary, there is a strong decoupling between DP and SS (and thus PP) during most of the floods (no significant correlation), with DP concentration peaks

  20. Ethics in Animal-Based Research.

    Science.gov (United States)

    Gross, Dominik; Tolba, René H

    2015-01-01

    In recent years, there have been a number of new demands and regulations which have reignited the discussion on ethics in animal-based research. In the light of this development, the present review first presents an overview of underlying core ethical questions and issues. This is followed by an outline of the current discussion on whether animals (used for experimentation) should have rights ascribed to them and whether animals need to have certain characteristics in order to be the beneficiaries of rights. The discourse on concepts of sentience and the 'sociozoological scale' in particular is mapped out in this regard. There follows an outline of relevant ethical positions and current moral approaches to animal-based research (animal rights position, utilitarianism, 'convergence position', intrinsic cultural value of fundamental research, 'contractarianism', anthropocentrism, principle of the three Rs). PMID:25871531

  1. Assessing inorganic contaminants in alternative phosphorus sources used in animal nutrition - A particular feature for the agricultural policies

    International Nuclear Information System (INIS)

    Full text: Since feed and fodder are the major limiting factors in enhancing animal husbandry productivity, improvements in feeding and nutrition should aid in making animal production more profitable. Phosphorus is one of the most important elements in man and animal nutrition, especially in tropical conditions. There are many phosphorus-containing products to satisfy any P recommendation in animal diets. It is mandatory to predict the presence of any hazardous element before indicate phosphate as supplemental phosphorus in animal nutrition, as long their hazardous contents are quite variable and these elements may cause several problems in animal and man health and nutrition. The first goal of this study was to assess inorganic and radiological aspects of eight different phosphorus sources: calcinated bone meal (FAR), dicalcium phosphate (BIC), super triple phosphate (FST), super simple phosphate (FSS), monoammonium phosphate (FMA), sulphur ammonium phosphate (FSA), ammoniated calcium polyphosphate (POLI) and a bovine mineral supplement (SMB). The multielemental analysis of P sources and muscle tissues were carried out using the nuclear technique named Neutron Activation Analysis. Irradiations took place at the IPR-R1 Triga Reactor from the CDTN/CNEN, Belo Horizonte, Brazil. Some toxic elements (Al, As, Ba, Cd, Mg, Mn, Th and U) were identified in some products, especially in the sulphur ammonium phosphate. Natural radiation from the following radionuclides 226Ra, 228Ra, and 40K present in the products were assessed by the Gamma Spectrometry technique using a hyper pure germanium detector (HPGe). The results are examined in the light of standards for exposure adopted in some countries including from Brazil. Some products present radioactivity in high levels, especially super simple phosphate. The second aim of this project was to evaluate the zootecnic responses of using these products in feeding growing rabbits. To accomplish this goal, it was undertaken an

  2. Hydrology, phosphorus, and suspended solids in five agricultural streams in the Lower Fox River and Green Bay Watersheds, Wisconsin, Water Years 2004-06

    Science.gov (United States)

    Graczyk, David J.; Robertson, Dale M.; Baumgart, Paul D.; Fermanich, Kevin J.

    2011-01-01

    A 3-year study was conducted by the U.S. Geological Survey and the University of Wisconsin-Green Bay to characterize water quality in agricultural streams in the Fox/Wolf watershed in northeastern Wisconsin and provide information to assist in the calibration of a watershed model for the area. Streamflow, phosphorus, and suspended solids data were collected between October 1, 2003, and September 30, 2006, in five streams, including Apple Creek, Ashwaubenon Creek, Baird Creek, Duck Creek, and the East River. During this study, total annual precipitation was close to the 30-year normal of 29.12 inches. The 3-year mean streamflow was highest in the East River (113 ft3/s), followed by Duck Creek (58.2 ft3/s), Apple Creek (26.9 ft3/s), Baird Creek (12.8 ft3/s), and Ashwaubenon Creek (9.1 ft3/s). On a yield basis, during these three years, the East River had the highest flow (0.78 ft3/s/mi2), followed by Baird Creek (0.61 ft3/s/mi2), Apple Creek (0.59 ft3/s/mi2), Duck Creek (0.54 ft3/s/mi2), and Ashwaubenon Creek (0.46 ft3/s/mi2). The overall median total suspended solids (TSS) concentration was highest in Baird Creek (73.5 mg/L), followed by Apple and Ashwaubenon Creeks (65 mg/L), East River (40 mg/L), and Duck Creek (30 mg/L). The median total phosphorus (TP) concentration was highest in Ashwaubenon Creek (0.60 mg/L), followed by Baird Creek (0.47 mg/L), Apple Creek (0.37 mg/L), East River (0.26 mg/L), and Duck Creek (0.22 mg/L).

  3. Agricultural production - Phase 2. Indonesia. Sources and sinks of nitrogen-E phosphorus-based nutrients in cropping systems

    International Nuclear Information System (INIS)

    This document is the report of an expert mission to assist in the initiation of research on sustainable agriculture in rice-based cropping systems as related to the flow of plant nutrients, and on the use of legumes in upland cropping systems. Experimental suggestions include an investigation of the acid tolerance of different soybean strains under upland conditions, an analysis of ways to replace fertilizer nitrogen for rice crops by a green manure such as azolla, and a study of the increase in nutrient availability due to th presence of fish in a paddy field

  4. Exploring the impact of agriculture on nitrogen and phosphorus biogeochemistry in global rivers during the twentieth century (Invited)

    Science.gov (United States)

    Bouwman, L.; Beusen, A.; Van Beek, L. P.

    2013-12-01

    Nutrients are transported from land to sea through the continuum formed by soils, groundwater, riparian zones, floodplains, streams, rivers, lakes, and reservoirs. The hydrology, ecology and biogeochemical processing in each of these components are strongly coupled and result in retention of a significant fraction of the nutrients transported. This paper analyzes the global changes in nutrient biogeochemical processes and retention in rivers during the past century (1900-2000); this period encompasses dramatic increases in human population and economic human activities including agriculture that have resulted in major changes in land use, nutrient use in agriculture, wastewater flows and human interventions in the hydrology (1). We use the hydrological PCR-GLOBWB model (2) for the period 1900-2000, including climate variability and the history of dam construction and land use conversion. Global agricultural and natural N and P soil budgets for the period 1900-2000 are the starting point to simulate nutrient flows from the soil via surface runoff and leaching through the groundwater system and riparian zones. In-stream processes are described with the nutrient spiraling concept. In the period 1900-2000, the global soil N budget surplus (inputs minus withdrawal in harvested crops) for agricultural and natural ecosystems increased from 118 to 202 Tg yr-1, and the global P budget increased from river nutrient export has increased rapidly in the 20th century. Model results are sensitive to factors determining the N and P delivery, as well as in-stream processes. The most uncertain factors are N delivery to streams by groundwater (denitrification as a function of thickness and reactivity of aquifers), and in-stream N and P retention parameters (net uptake velocity, retention as function of concentration). References 1. Bouwman AF, Beusen AHW, Griffioen J, Van Groenigen JW, Hefting MM, Oenema O, et al. Global trends and uncertainties in terrestrial denitrification and N2O

  5. Animal-based measures for welfare assessment

    Directory of Open Access Journals (Sweden)

    Agostino Sevi

    2010-01-01

    Full Text Available Animal welfare assessment can’t be irrespective of measures taken on animals. Indeed, housing parametersrelatedtostructures, designandmicro-environment, evenifreliable parameters related to structures, design and micro-environment, even if reliable and easier to take, can only identify conditions which could be detrimental to animal welfare, but can’t predict poor welfare in animals per se. Welfare assessment through animal-based measures is almost complex, given that animals’ responses to stressful conditions largely depend on the nature, length and intensity of challenges and on physiological status, age, genetic susceptibility and previous experience of animals. Welfare assessment requires a multi-disciplinary approach and the monitoring of productive, ethological, endocrine, immunological and pathological param- eters to be exhaustive and reliable. So many measures are needed, because stresses can act only on some of the mentioned parameters or on all of them but at different times and degree. Under this point of view, the main aim of research is to find feasible and most responsive indicators of poor animal welfare. In last decades, studies focused on the following parameters for animal wel- fare assessment indexes of biological efficiency, responses to behavioral tests, cortisol secretion, neutrophil to lymphocyte ratio, lymphocyte proliferation, production of antigen specific IgG and cytokine release, somatic cell count and acute phase proteins. Recently, a lot of studies have been addressed to reduce handling and constraint of animals for taking measures to be used in welfare assessment, since such procedures can induce stress in animals and undermined the reliability of measures taken for welfare assessment. Range of animal-based measures for welfare assessment is much wider under experimental condition than at on-farm level. In welfare monitoring on-farm the main aim is to find feasible measures of proved validity and reliability

  6. The impact of biochars prepared from agricultural residues on phosphorus release and availability in two fertile soils.

    Science.gov (United States)

    Manolikaki, Ioanna I; Mangolis, Argirios; Diamadopoulos, Evan

    2016-10-01

    Biochars have a high variability in chemical composition, which is influenced by pyrolysis conditions and type of biomass. Essential macronutrient P retained in biochar could be released and made available to plants, enhancing plant growth. This study was conducted in order to evaluate whether biochar, produced from agricultural residues, could release P in water, as well as study its potential effect on plant growth and P uptake. Biochar samples were prepared from rice husks, grape pomace and olive tree prunings by pyrolysis at 300 °C and 500 °C. These samples were used for P batch successive leaching experiments in order to determine P release in water. Subsequently, rice husk and grape pomace biochars, produced by pyrolysis at 300 °C, were applied to two temperate soils with highly different pH. A three-month cultivation period of ryegrass (Lolium perenne L.) was studied in threefold replication, while three harvests were accomplished. Treatments comprised control soils (without amendment) and soils amended only with biochar. Results of P leaching tests showed a continuous release of P from all biochars as compared to raw biomass samples, for which the highest P concentrations were detected during the first extraction. Grape pomace and rice husk biochars pyrolyzed at 500 °C showed higher levels of water-extractable P, as compared to their corresponding raw biomass. Biochars, at 500 °C, leached more P in all four extractions, compared to biochars at 300 °C, apart from olive tree prunings biochars, where both pyrolysis temperatures presented a similar trend. Concerning plant yield of ryegrass, rice husk and grape pomace biochars showed positive statistically significant effects on plant yield only in slightly acidic soil in second and third harvests. In terms of P uptake of ryegrass, grape pomace biochars depicted positive significant differences (P < 0.05) in third harvest, in slightly acidic soil, while in first and second harvests positive

  7. The impact of biochars prepared from agricultural residues on phosphorus release and availability in two fertile soils.

    Science.gov (United States)

    Manolikaki, Ioanna I; Mangolis, Argirios; Diamadopoulos, Evan

    2016-10-01

    Biochars have a high variability in chemical composition, which is influenced by pyrolysis conditions and type of biomass. Essential macronutrient P retained in biochar could be released and made available to plants, enhancing plant growth. This study was conducted in order to evaluate whether biochar, produced from agricultural residues, could release P in water, as well as study its potential effect on plant growth and P uptake. Biochar samples were prepared from rice husks, grape pomace and olive tree prunings by pyrolysis at 300 °C and 500 °C. These samples were used for P batch successive leaching experiments in order to determine P release in water. Subsequently, rice husk and grape pomace biochars, produced by pyrolysis at 300 °C, were applied to two temperate soils with highly different pH. A three-month cultivation period of ryegrass (Lolium perenne L.) was studied in threefold replication, while three harvests were accomplished. Treatments comprised control soils (without amendment) and soils amended only with biochar. Results of P leaching tests showed a continuous release of P from all biochars as compared to raw biomass samples, for which the highest P concentrations were detected during the first extraction. Grape pomace and rice husk biochars pyrolyzed at 500 °C showed higher levels of water-extractable P, as compared to their corresponding raw biomass. Biochars, at 500 °C, leached more P in all four extractions, compared to biochars at 300 °C, apart from olive tree prunings biochars, where both pyrolysis temperatures presented a similar trend. Concerning plant yield of ryegrass, rice husk and grape pomace biochars showed positive statistically significant effects on plant yield only in slightly acidic soil in second and third harvests. In terms of P uptake of ryegrass, grape pomace biochars depicted positive significant differences (P < 0.05) in third harvest, in slightly acidic soil, while in first and second harvests positive

  8. The surprisingly small but increasing role of international agricultural trade on the European Union’s dependence on mineral phosphorus fertiliser

    Science.gov (United States)

    Nesme, Thomas; Roques, Solène; Metson, Geneviève S.; Bennett, Elena M.

    2016-02-01

    Phosphorus (P) is subject to global management challenges due to its importance to both food security and water quality. The European Union (EU) has promoted policies to limit fertiliser over-application and protect water quality for more than 20 years, helping to reduce European P use. Over this time period, the EU has, however, become more reliant on imported agricultural products. These imported products require fertiliser to be used in distant countries to grow crops that will ultimately feed European people and livestock. As such, these imports represent a displacement of European P demand, possibly allowing Europe to decrease its apparent P footprint by moving P use to locations outside the EU. We investigated the effect of EU imports on the European P fertiliser footprint to better understand whether the EU’s decrease in fertiliser use over time resulted from P demand being ‘outsourced’ to other countries or whether it truly represented a decline in P demand. To do this, we quantified the ‘virtual P flow’ defined as the amount of mineral P fertiliser applied to agricultural soils in non-EU countries to support agricultural product imports to the EU. We found that the EU imported a virtual P flow of 0.55 Tg P/yr in 1995 that, surprisingly, decreased to 0.50 Tg P/yr in 2009. These results were contrary to our hypothesis that trade increases would be used to help the EU reduce its domestic P fertiliser use by outsourcing its P footprint abroad. Still, the contribution of virtual P flows to the total P footprint of the EU has increased by 40% from 1995 to 2009 due to a dramatic decrease in domestic P fertiliser use in Europe: in 1995, virtual P was equivalent to 32% of the P used as fertiliser domestically to support domestic consumption but jumped to 53% in 2009. Soybean and palm tree products from South America and South East Asia contributed most to the virtual P flow. These results demonstrate that, although policies in the EU have successfully

  9. Biomass carbon, nitrogen and phosphorus stocks in hybrid poplar buffers, herbaceous buffers and natural woodlots in the riparian zone on agricultural land.

    Science.gov (United States)

    Fortier, Julien; Truax, Benoit; Gagnon, Daniel; Lambert, France

    2015-05-01

    In many temperate agricultural areas, riparian forests have been converted to cultivated land, and only narrow strips of herbaceous vegetation now buffer many farm streams. The afforestation of these riparian zones has the potential to increase carbon (C) storage in agricultural landscapes by creating a new biomass sink for atmospheric CO2. Occurring at the same time, the storage of nitrogen (N) and phosphorus (P) in plant biomass, is an important water quality function that may greatly vary with types of riparian vegetation. The objectives of this study were (1) to compare C, N and P storage in aboveground, belowground and detrital biomass for three types of riparian vegetation cover (9-year-old hybrid poplar buffers, herbaceous buffers and natural woodlots) across four agricultural sites and (2) to determine potential vegetation cover effects on soil nutrient supply rate in the riparian zone. Site level comparisons suggest that 9-year-old poplar buffers have stored 9-31 times more biomass C, 4-10 times more biomass N, and 3-7 times more biomass P than adjacent non managed herbaceous buffers, with the largest differences observed on the more fertile sites. The conversion of these herbaceous buffers to poplar buffers could respectively increase C, N and P storage in biomass by 3.2-11.9 t/ha/yr, 32-124 kg/ha/yr and 3.2-15.6 kg/ha/yr, over 9 years. Soil NO3 and P supply rates during the summer were respectively 57% and 66% lower in poplar buffers than in adjacent herbaceous buffers, potentially reflecting differences in nutrient storage and cycling between the two buffer types. Biomass C ranged 49-160 t/ha in woodlots, 33-110 t/ha in poplar buffers and 3-4 t/ha in herbaceous buffers. Similar biomass C stocks were found in the most productive poplar buffer and three of the four woodlots studied. Given their large and varied biomass C stocks, conservation of older riparian woodlots is equally important for C balance management in farmland. In addition, the

  10. Sustainable Phosphorus Measures: Strategies and Technologies for Achieving Phosphorus Security

    Directory of Open Access Journals (Sweden)

    Stuart White

    2013-01-01

    Full Text Available Phosphorus underpins the world’s food systems by ensuring soil fertility, maximising crop yields, supporting farmer livelihoods and ultimately food security. Yet increasing concerns around long-term availability and accessibility of the world’s main source of phosphorus—phosphate rock, means there is a need to investigate sustainable measures to buffer the world’s food systems against the long and short-term impacts of global phosphorus scarcity. While the timeline of phosphorus scarcity is contested, there is consensus that more efficient use and recycling of phosphorus is required. While the agricultural sector will be crucial in achieving this, sustainable phosphorus measures in sectors upstream and downstream of agriculture from mine to fork will also need to be addressed. This paper presents a comprehensive classification of all potential phosphorus supply- and demand-side measures to meet long-term phosphorus needs for food production. Examples range from increasing efficiency in the agricultural and mining sector, to technologies for recovering phosphorus from urine and food waste. Such measures are often undertaken in isolation from one another rather than linked in an integrated strategy. This integrated approach will enable scientists and policy-makers to take a systematic approach when identifying potential sustainable phosphorus measures. If a systematic approach is not taken, there is a risk of inappropriate investment in research and implementation of technologies and that will not ultimately ensure sufficient access to phosphorus to produce food in the future. The paper concludes by introducing a framework to assess and compare sustainable phosphorus measures and to determine the least cost options in a given context.

  11. 地膜覆盖对农田径流中氮磷流失的影响%The Effected of Mulch Film on Nitrogen and Phosphorus Loss in Agricultural Runoff

    Institute of Scientific and Technical Information of China (English)

    邓伟; 许振成; 吴根义; 贺德春

    2011-01-01

    [ Objective] The aim of the study was to seek a good way to reduce nitrogen and phosphorus loss in agricultural runoff. [ Method] The effect of three kinds of mulch film: plastic film mulching, straw mulching,none mulching on nitrogen and phosphorus loss in agriculture was investigated. [Result]The results showed that: Although mulching increased runoff,reduced the rains washed out planting soil,so the concentration and total loss of nitrogen and phosphorus in runoff was lowered; The land of plastic film mulching add more runoff,but total loss of nitrogen and phosphorus was lowest; The land of straw mulching had a little more total loss of nitrogen and phosphorus then the land of plastic film mulching,but the output of crops was higher then the land of plastic film mulching and none secondarypollutant. [ Conclusion] Straw mulching could reduce nitrogen and phosphorus loss in agricultural runoff, improve the output of crops and no secondarypollutant emission. So straw was a good cultivated ways.%[目的]减少农田氮磷的径流流失.[方法]研究3种不同地膜覆盖:塑料覆盖,桔杆覆盖和无覆盖方式对农田氮磷径流流失的影响.[结果]地膜覆盖增加了径流量,但减少了雨水对种植土壤的冲刷,降低了径流中氮磷的浓度,从而减少了径流中氮磷的流失;塑料薄膜覆盖地块增加的径流较多,但氮磷流失总量最少;桔秆覆盖地块产生的氮磷流失量略大于塑料薄膜覆盖地块,但作物产量高于塑料薄膜地块,同时不会产生二次污染[结论]桔杆地膜覆盖可以减少农田氮磷的径流流失,增加产量,且不产生二次污染,是较好的农作方式.

  12. The Relevance of Phosphorus and Iron Chemistry to the Recovery of Phosphorus from Wastewater: A Review.

    Science.gov (United States)

    Wilfert, Philipp; Kumar, Prashanth Suresh; Korving, Leon; Witkamp, Geert-Jan; van Loosdrecht, Mark C M

    2015-08-18

    The addition of iron is a convenient way for removing phosphorus from wastewater, but this is often considered to limit phosphorus recovery. Struvite precipitation is currently used to recover phosphorus, and this approach has attracted much interest. However, it requires the use of enhanced biological phosphorus removal (EBPR). EBPR is not yet widely applied and the recovery potential is low. Other phosphorus recovery methods, including sludge application to agricultural land or recovering phosphorus from sludge ash, also have limitations. Energy-producing wastewater treatment plants increasingly rely on phosphorus removal using iron, but the problem (as in current processes) is the subsequent recovery of phosphorus from the iron. In contrast, phosphorus is efficiently mobilized from iron by natural processes in sediments and soils. Iron-phosphorus chemistry is diverse, and many parameters influence the binding and release of phosphorus, including redox conditions, pH, presence of organic substances, and particle morphology. We suggest that the current poor understanding of iron and phosphorus chemistry in wastewater systems is preventing processes being developed to recover phosphorus from iron-phosphorus rich wastes like municipal wastewater sludge. Parameters that affect phosphorus recovery are reviewed here, and methods are suggested for manipulating iron-phosphorus chemistry in wastewater treatment processes to allow phosphorus to be recovered. PMID:25950504

  13. Phosphorus dynamics in Swedish agricultural soils as influenced by fertilization and mineralogical properties: Insights gained from batch experiments and XANES spectroscopy.

    Science.gov (United States)

    Eriksson, Ann Kristin; Hesterberg, Dean; Klysubun, Wantana; Gustafsson, Jon Petter

    2016-10-01

    The soil chemistry of phosphorus (P) is important for understanding the processes governing plant availability as well as the risk of environmental losses of P. The objective of this research was to investigate both the speciation and the pH-dependent solubility patterns of P in clayey agricultural soils in relation to soil mineralogy and fertilization history. The study focused on soil samples from six fields that were subjected to different P fertilization regimes for periods of 45 to 57years. Soil P speciation was analyzed by P K-edge XANES spectroscopy and chemical fractionation, sorption isotherms were constructed, and dissolved P was measured as a function of pH. The XANES fitting results showed that organic P and P adsorbed to Fe and Al (hydr)oxides were common P constituents in all soils. Calcium phosphates were identified in five of six soil samples. The XANES results also indicated an increase in P adsorbed to Al and to a lesser extent Fe (hydr)oxides as a result of fertilization. Moreover, the fluorescence intensity from the P K-edge XANES analysis was most strongly correlated with HCl-digestible P (r=0.81***). Consistent with the XANES analysis, laboratory sorption isotherm models showed that the Freundlich sorption coefficient (KF) was most closely related to oxalate-extractable Al. Greater proportions of Ca phosphate in two of the heavily fertilized soils in combination with enhanced PO4 solubilization upon sample acidification indicated neoformation of Ca-phosphate precipitates. The results for the unfertilized soil samples generally showed a minimum in dissolved PO4 between pH6.5 and 7.5, with increases particularly at lower pH. This behavior can be explained either by the dissolution of Al-hydroxide-type sorbents or Ca phosphates at lower pH. In fertilized soils, there was no consistent trend in pH-dependent solubilization of P, with a complex relationship to solid-phase speciation. To conclude, inorganic P species changed most dynamically in

  14. Phosphorus dynamics in Swedish agricultural soils as influenced by fertilization and mineralogical properties: Insights gained from batch experiments and XANES spectroscopy.

    Science.gov (United States)

    Eriksson, Ann Kristin; Hesterberg, Dean; Klysubun, Wantana; Gustafsson, Jon Petter

    2016-10-01

    The soil chemistry of phosphorus (P) is important for understanding the processes governing plant availability as well as the risk of environmental losses of P. The objective of this research was to investigate both the speciation and the pH-dependent solubility patterns of P in clayey agricultural soils in relation to soil mineralogy and fertilization history. The study focused on soil samples from six fields that were subjected to different P fertilization regimes for periods of 45 to 57years. Soil P speciation was analyzed by P K-edge XANES spectroscopy and chemical fractionation, sorption isotherms were constructed, and dissolved P was measured as a function of pH. The XANES fitting results showed that organic P and P adsorbed to Fe and Al (hydr)oxides were common P constituents in all soils. Calcium phosphates were identified in five of six soil samples. The XANES results also indicated an increase in P adsorbed to Al and to a lesser extent Fe (hydr)oxides as a result of fertilization. Moreover, the fluorescence intensity from the P K-edge XANES analysis was most strongly correlated with HCl-digestible P (r=0.81***). Consistent with the XANES analysis, laboratory sorption isotherm models showed that the Freundlich sorption coefficient (KF) was most closely related to oxalate-extractable Al. Greater proportions of Ca phosphate in two of the heavily fertilized soils in combination with enhanced PO4 solubilization upon sample acidification indicated neoformation of Ca-phosphate precipitates. The results for the unfertilized soil samples generally showed a minimum in dissolved PO4 between pH6.5 and 7.5, with increases particularly at lower pH. This behavior can be explained either by the dissolution of Al-hydroxide-type sorbents or Ca phosphates at lower pH. In fertilized soils, there was no consistent trend in pH-dependent solubilization of P, with a complex relationship to solid-phase speciation. To conclude, inorganic P species changed most dynamically in

  15. Constructed Wetlands and Buffer Zones as Measures for Agricultural Phosphorus Leakage on a Sub-catchment Scale : The Söderköping River Project

    OpenAIRE

    Kokic, Jovana

    2010-01-01

    The Baltic Sea has a major problem with eutrophication where acts have been taken by the EU commission to sign a common action plan, the Baltic Sea Action Plan (BSAP). The overall goal is to reach a good environmental status by the year 2021, where one of the sub-goals is that the Baltic Sea should be unaffected by eutrophication. For Sweden, the goal for phosphorus (P) is to reduce the annual load with 290 tonnes by the year 2021. Since phosphorus is the main limiting nutrient, it is targete...

  16. Nitrogen and Phosphorus Loads in an Agricultural Watershed Affected by Poultry Litter Application and Wastewater Effluent, Northeastern Oklahoma and Northwestern Arkansas, 2002-2009

    Science.gov (United States)

    Esralew, R.; Tortorelli, R. L.

    2010-12-01

    The Eucha-Spavinaw Basin in Northeastern Oklahoma and Northwestern Arkansas is the source of water for Lake Eucha and Spavinaw Lake, which are part of the water supply for the city of Tulsa, Oklahoma. Lake Eucha and Spavinaw Lakes have experienced deteriorating water quality largely due to growth of algae, notably cyanobacteria, from the excess input of nutrients. As a result, the city of Tulsa has spent millions of dollars to eliminate taste and odor problems resulting from production of algal and bacterial byproducts. To evaluate changes in nutrient loading resulting from a reduction in land application of poultry litter, installation of best management practices, and reductions in the phosphorus concentrations in wastewater effluent, the U.S. Geological Survey investigated nitrogen and phosphorus concentrations from samples collected during baseflow and runoff and used regression models to estimate nitrogen and phosphorus loads, yields, and flow-weighted concentrations in two major tributaries to Lake Eucha, Spavinaw and Beaty Creeks, for the period 2002-2009. Estimated mean flow-weighted total unfiltered nitrogen and phosphorus concentrations in the basin were about 5 to 10 times greater than the 75th percentile of flow-weighted nutrient concentrations in other mostly undeveloped basins of the United States. Spavinaw and Beaty Creeks contributed an estimated mean annual total load of about 762,500 kilograms of nitrogen and 49,200 kilograms of phosphorus per year, 76 to 91 percent of which was transported to Lake Eucha by runoff. Thirty-four percent of the nitrogen load and 48 percent of the phosphorus load to Lake Eucha occurred during the year 2008 which was the wettest year on record for the Eucha-Spavinaw Basin. The results of this analysis indicate that although efforts were made to control nutrient loading, nutrient concentrations, especially phosphorus, were substantially augmented by non-point sources and that most loading occurs during runoff events

  17. Environmental Phosphorus Recovery Based on Molecular Bioscavengers

    DEFF Research Database (Denmark)

    Gruber, Mathias Felix

    pressure to develop sustainable phosphorus practices as well as new technologies for phosphorus recovery. Nature has spent billions of years refining proteins that interact with phosphates. This has inspired the present work where the overall ambitions are: to facilitate the development of a recovery......Phosphorus is a ubiquitous element of all known life and as such it is found throughout numerous key molecules related to various cellular functions. The supply of phosphorus is tightly linked to global food security, since phosphorus is used to produce agricultural fertilizers, without which it...... would not be possible to feed the world population. Sadly, the current supply of phosphorus is based on the gradual depletion of limited fossil reserves, and some estimates predict that within 15-25 years we will consume more phosphorus than we can produce. There is therefore a strong international...

  18. Regional Substance Flow Analysis for Assessment of Long-term Phosphorus Accumulation in Soil

    OpenAIRE

    Zabrodina, Marina Vladimirovna

    2013-01-01

    Phosphorus is a non-renewable resource that is essential for food production. At the same time, phosphorus may cause environmental problems because excess phosphorus in agricultural soil often leads to eutrophication. For rational and sound phosphorus management in order to mitigate resource scarcity and eutrophication problems, reliable estimates of phosphorus pools and flows and the understanding of phosphorus soil dynamics are needed. Studies in Material Flow Analysis that consider soil ph...

  19. Investigating User Experiences Through Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter; Poulsen, Søren Bolvig

    graphics and animation to sketch design ideas into diegetic design solutions. Through a deep-dive into two cases we discuss how animation-based sketching techniques supports the investigation of user experience aspects in design scenarios, and wether the expression is dependent on the visual fidelity or on......This paper discusses the use of animation-based sketching as an approach to explore diegetic designs in the fuzzy front-end ideation of the design process. We present the results from a design workshop with more than 200 participating design students, and 16 companies. The participants used motion...... how animation is applied to support a design narrative anchoring to the context....

  20. Phosphorus Recovery from Ashes of Sewage Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Cornel, Peter; Schaum, Peter

    2003-07-01

    About 90% of the incoming phosphorus load of waste water is eliminated by waste water treatment and transferred into the sewage sludge. Considerable amounts of sewage sludge can not be used agriculturally but are incinerated. Thus the ash from mono sludge incineration plants contains significant amounts of phosphorus (up to 25% P{sub 2}O{sub 5}) and could be used as raw material in fertilizer industry. The ash is hygienically harmless and free of organic substances. The ratio of phosphorus to heavy metals is basically the same as in the sewage sludge. The first step in separating phosphorus from heavy metals is to dissolve phosphorus by extraction. The most promising way seems to be the release of phosphorus with acids or bases. With 1 m sulphuric acid it is possible to release phosphorus completely. By use of acid most of the heavy metals dissolve, too. With caustic soda as solvent, only 30-40% of the phosphorus can be dissolved but the eluate is almost free of heavy metals. The amount of phosphorus which can be released with caustic soda, depends on the applied precipitant (Al or Fe salts) for phosphorus elimination at the waste water treatment. (author)

  1. Painful dilemmas: the ethics of animal-based pain research

    DEFF Research Database (Denmark)

    Magalhães-Sant'Ana, M.; Sandøe, Peter; Olsson, I. A. S.

    2009-01-01

    While it has the potential to deliver important human benefits, animal-based pain research raises ethical questions, because it involves inducing pain in sentient beings. Ethical decision-making, connected with this variety of research, requires informed harm-benefit analysis, and the aim of this...

  2. Reduction of hazardous levels of the agricultural application of nitrogen and phosphorus relative to toxic ground water and toxic levels in the soil.

    Science.gov (United States)

    Jackson, W R

    2000-10-01

    This paper proposes the hypothesis that microbial life chemically reduces levels of nitrogen (N(2)) and phosphorus (P) that are toxic and threaten human health and safety. Bio-remediation uses microorganisms to decontaminate a polluted system, in situ, requiring a minimal amount of space and equipment. Data strongly suggest that bio-stimulation can assist one microbe to multiply up to one billion microorganisms in 24 hours. Biochemical literature postulates that microbial life chemically biodegrades nitrates by one of two methods: (1) assimilative reduction; or (2) dissimilative reduction, also known as denitrification. Assimilative reduction results in construction of microbial cell walls, cell membranes and various forms of amino acids. It is proposed that denitrification includes the venting-off of the excess amounts of N(2)not required by the soil or needed for additional microbial development. Nitrate reduction by way of denitrification is a functional part of anaerobic respiration. Alternatively, the denitrification process supports oxidative phosphorylation, a mechanism similar to aerobic respiration. Thus, denitrification and phosphorylation may be considered as forms of respiration. PMID:11000054

  3. Investigating User Experiences Through Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter; Poulsen, Søren Bolvig

    2016-01-01

    This paper discusses the use of animation-based sketching as an approach to explore diegetic designs in the fuzzy front-end ideation of the design process. We present the results from a design workshop with more than 200 partic- ipating design students, and 16 companies. The participants used...... motion graphics and animation to sketch design ideas into diegetic design solutions. Through a deep-dive into two cases studies we discuss how animation-based sketching techniques supported the investigation of user experience aspects in design scenarios, and whether the expression is dependent...... on the visual delity or on how animation is ap- plied to support a design narrative anchoring to the context....

  4. PSYCHIC A process-based model of phosphorus and sediment mobilisation and delivery within agricultural catchments. Part 1: Model description and parameterisation

    Science.gov (United States)

    Davison, Paul S.; Withers, Paul J. A.; Lord, Eunice I.; Betson, Mark J.; Strömqvist, Johan

    2008-02-01

    SummaryPSYCHIC is a process-based model of phosphorus (P) and suspended sediment (SS) mobilisation in land runoff and subsequent delivery to watercourses. Modelled transfer pathways include release of desorbable soil P, detachment of SS and associated particulate P, incidental losses from manure and fertiliser applications, losses from hard standings, the transport of all the above to watercourses in underdrainage (where present) and via surface pathways, and losses of dissolved P from point sources. The model can operate at two spatial scales, although the scientific core is the same in both cases. At catchment scale, the model uses easily available national scale datasets to infer all necessary input data whilst at field scale, the user is required to supply all necessary data. The model is sensitive to a number of crop and animal husbandry decisions, as well as to environmental factors such as soil type and field slope angle. It is envisaged that the catchment-scale model would provide the first tier of a catchment characterisation study, and would be used as a screening tool to identify areas within the catchment which may be at elevated risk of P loss. This would enable targeted data collection, involving farm visits and stakeholder discussion, which would then be followed up with detailed field-scale modelling. Both tiers allow the effects of possible mitigation options at catchment scale (Tier 1) and field scale (Tier 2) to be explored. The PSYCHIC model framework therefore provides a methodology for identifying critical source areas of sediment and P transfer in catchments and assessing what management changes are required to achieve environmental goals.

  5. Robot Animals Based on Brain-Computer Interface

    Institute of Scientific and Technical Information of China (English)

    Yang Xia; Lei Lei; Tie-Jun Liu; De-Zhong Yao

    2009-01-01

    The study of robot animals based on brain-computer interface (BCI) technology is an important field in robots and neuroscience at present.In this paper,the development status at home and abroad of the motion control of robot based on BCI and principle of robot animals are introduced,then a new animals' behavior control method by photostimulation is presented.At last,the application prospect is provided.

  6. 太湖流域农业面源氮磷流失生态拦截工程技术%Technologies for Ecological Interception of Nitrogen and Phosphorus Loss from Agricultural Non-point Source in Taihu Lake Basin

    Institute of Scientific and Technical Information of China (English)

    杨雪; 梅凯; 吴昊

    2012-01-01

    研究表明,农业生产已成为太湖流域农业面源污染的重要因素,其中农田径流污染所占比例较大.以太湖流域氮磷流失生态拦截工程为例,阐述了水体生态修复技术的原理及具体技术措施,包括生态拦截沟渠、溢流坝、净化塘等,并进行了环境效益分析.%Agricultural production is an important factor of non-point source pollution in Taihu Lake basin, in which arable land runoff pollution accounts for a large proportion. Taking the ecological interception project of nitrogen and phosphorus loss in Taihu Lake basin for example, the principle and specific technical measures including ecological interception ditch and channel, spillway dam and ecological purifying pond were described, and the environmental benefit was analyzed.

  7. Displacement of phosphorus in structured soils

    OpenAIRE

    Djodjic, Faruk

    2001-01-01

    Phosphorus losses from agriculture may enhance eutrophication of fresh water bodies. This thesis focuses on preferential flow as a phosphorus transport pathway. Both lysimeter and field plot observations were conducted to evaluate the significance of preferential flow for P losses and to test management practices to reduce P losses. A decision support system was also developed to identify critical source areas, to diagnose probable causes of P losses and to prescribe appropriate site-specific...

  8. Return of phosphorus in agricultural residues and urban sewage sludge to soil using biochar from low-temperature gasification as fertilizer product

    DEFF Research Database (Denmark)

    Müller-Stöver, Dorette Sophie; Jensen, Lars Stoumann; Grønlund, Mette;

    from different biomass fuels, such as agricultural residues and waste streams, and at the same time producing a biochar product potentially valuable for soil amendment. In pot experiments, different residual products originating from low-temperature gasification were tested for their P...... fertilization purposes. Operationally defined P pools in soil obtained by sequential chemical extraction of the biochar-amended soils could be related to the observations made in the pot experiments. The results emphasize the potential of combining different feedstocks for thermal conversion processes when......-fertilizing potential with spring barley as a test crop. Biochar resulting from gasification of pure wheat straw showed the best P fertilizer value, however, because of the low P content, extremely high amounts had to be applied when crop P demand should be met, which came along with an over-fertilization of potassium...

  9. Sustainable use of phosphorus: a finite resource.

    Science.gov (United States)

    Scholz, Roland W; Ulrich, Andrea E; Eilittä, Marjatta; Roy, Amit

    2013-09-01

    Phosphorus is an essential element of life and of the modern agricultural system. Today, science, policy, agro-industry and other stakeholder groups are increasingly concerned about the sustainable use of this resource, given the dissipative nature of phosphorus and difficulties in assessing, evaluating, and coping with phosphorus pollution in aquatic and terrestrial systems. We argue that predictions about a forthcoming peak, followed by a quick reduction (i.e., physical phosphate rock scarcity) are unreasoned and stress that access to phosphorus (economic scarcity) is already, and may increasingly become critical, in particular for smallholders farmers in different parts of the world. The paper elaborates on the design, development, goals and cutting-edge contributions of a global transdisciplinary process (i.e. mutual learning between science and society including multiple stakeholders) on the understanding of potential contributions and risks related to the current mode of using phosphorus on multiple scales (Global TraPs). While taking a global and comprehensive view on the whole phosphorus-supply chain, Global TraPs organizes and integrates multiple transdisciplinary case studies to better answer questions which inform sustainable future phosphorus use. Its major goals are to contribute to four issues central to sustainable resource management: i) long-term management of biogeochemical cycles, in particular the challenge of closing the phosphorus cycle, ii) achieving food security, iii) avoiding environmental pollution and iv) sustainability learning on a global level by transdisciplinary processes. PMID:23769630

  10. Effect of Form and Amount of Phosphorus and Phytase Supplementation on Phosphorus Utilization by Ruminants

    OpenAIRE

    Shanklin, Rachel Kristina

    2001-01-01

    EFFECT OF AMOUNT AND FORM OF PHOSPHORUS AND PHYTASE SUPPLEMENTATION ON PHOSPHORUS UTILIZATION BY RUMINANTS by Rachel Kristina Shanklin Committee Chair, Joseph P. Fontenot Animal and Poultry Sciences (ABSTRACT) The use of animal manures to replace commercial fertilizer has increased the economic and environmental sustainability of agriculture. However, this practice has resulted in excess P being applied to the soil in some areas. Excess P may run-off into surface wa...

  11. Fontes de fósforo (fluida ou sólida na produtividade agrícola e industrial da cana-de-açúcar Effects of phosphorus sources (liquid or solid on agricultural and industrial sugarcane yield

    Directory of Open Access Journals (Sweden)

    Gaspar Henrique Korndörfer

    2009-02-01

    two fertilizers (superphosphates were applied in the granulated form and the last ones in the liquid form. The phosphorus fertilizers were applied on the furrow just before planting. The results allowed concluding that there was no difference between solid and liquid form in the agricultural and industrial productivity. After the third cut, the Agronomic Efficiency Index showed that phosphates source reduced in the following order: single superphosphate (110% > triple superphosphate (100% > phosphoric acid (73% > phosphoric acid + rock phosphate (48%.

  12. Use of reactive materials to bind phosphorus

    NARCIS (Netherlands)

    Chardon, W.J.; Groenenberg, J.E.; Temminghoff, E.J.M.; Koopmans, G.F.

    2012-01-01

    Phosphorus (P) losses from agricultural soils have caused surface water quality impairment in many regions of the world, including The Netherlands. Due to the large amounts of P accumulated in Dutch soils, the generic fertilizer and manure policy will not be sufficient to reach in time the surface w

  13. Data-driven facial animation based on manifold Bayesian regression

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Driving facial animation based on tens of tracked markers is a challenging task due to the complex topology and to the non-rigid nature of human faces. We propose a solution named manifold Bayesian regression. First a novel distance metric, the geodesic manifold distance, is introduced to replace the Euclidean distance. The problem of facial animation can be formulated as a sparse warping kernels regression problem, in which the geodesic manifold distance is used for modelling the topology and discontinuities of the face models. The geodesic manifold distance can be adopted in traditional regression methods, e.g. radial basis functions without much tuning. We put facial animation into the framework of Bayesian regression. Bayesian approaches provide an elegant way of dealing with noise and uncertainty. After the covariance matrix is properly modulated, Hybrid Monte Carlo is used to approximate the integration of probabilities and get deformation results. The experimental results showed that our algorithm can robustly produce facial animation with large motions and complex face models.

  14. Supply, demand and prices of phosphorus fertilizers market in Poland in 2004-2009

    OpenAIRE

    Piwowar, Arkadiusz

    2013-01-01

    The mineral fertilizers market is one of the most important markets for agricultural means of production. The phosphorus fertilizers are very important in this context because they are one of the most cropping agriculture factor with big potential possibilities. The aim of this article is to present the market of phosphorus fertilizers in Poland, taking into consideration the range of products offered, the demand for phosphorus fertilizers and changes in their prices.

  15. Assessing phosphorus reduction efforts in the Everglades

    Science.gov (United States)

    Tretkoff, Ernie

    2011-05-01

    Years of agricultural and urban runoff have resulted in too much phosphorus in northern regions of the Florida Everglades. To deal with this problem, very large constructed wetlands, known as Stormwater Treatment Areas (STAs), have been built to strip phosphorus from runoff before the water enters protected Everglades areas. The more than $1 billion STA project currently relies on large areas (cells) of submerged aquatic vegetation (SAV) to absorb phosphorus as the final stage of treatment. To evaluate how well the treatment cells are functioning, as well as the potential lower limits of treatment, it is essential to have an accurate picture of the inflows, outflows, and background phosphorus levels. Juston and DeBusk made long-term measurements in one of the SAV cells. They found that after total phosphorous levels in the cells reached about 15 micrograms per liter, no more phosphorus removal occurred. They also analyzed inflow and outflow data from the cell and inferred background phosphorus concentrations for eight additional SAV cells. Background concentrations averaged around 16 micrograms per liter. (Water Resources Research, doi:10.1029/2010WR009294, 2011)

  16. Developing Educational Computer Animation Based on Human Personality Types

    Directory of Open Access Journals (Sweden)

    Sajid Musa

    2015-03-01

    Full Text Available Computer animation in the past decade has become one of the most noticeable features of technology-based learning environments. By its definition, it refers to simulated motion pictures showing movement of drawn objects, and is often defined as the art in movement. Its educational application known as educational computer animation is considered to be one of the most elegant ways for preparing materials for teaching, and its importance in assisting learners to process, understand and remember information efficiently has vastly grown since the advent of powerful graphics-oriented computers era. Based on theories and facts of psychology, colour science, computer animation, geometric modelling and technical aesthetics, this study intends to establish an inter-disciplinary area of research towards a greater educational effectiveness. With today’s high educational demands as well as the lack of time provided for certain courses, classical educational methods have shown deficiencies in keeping up with the drastic changes observed in the digital era. Generally speaking, without taking into account various significant factors as, for instance, gender, age, level of interest and memory level, educational animations may turn out to be insufficient for learners or fail to meet their needs. Though, we have noticed that the applications of animation for education have been given only inadequate attention, and students’ personality types of temperaments (sanguine, choleric, melancholic, phlegmatic, etc. have never been taken into account. We suggest there is an interesting relationship here, and propose essential factors in creating educational animations based on students’ personality types. Particularly, we study how information in computer animation may be presented in a more preferable way based on font types and their families, colours and colour schemes, emphasizing texts, shapes of characters designed by planar quadratic Bernstein-Bézier curves

  17. Modelling heavy metal and phosphorus balances for farming systems

    NARCIS (Netherlands)

    Keller, A.N.; Schulin, R.

    2003-01-01

    Accounting for agricultural activities such as P fertilization in regional models of heavy metal accumulation provides suitable sustainable management strategies to reduce nutrient surpluses and metal inputs in agricultural soils. Using the balance model PROTERRA-S, we assessed the phosphorus ( P),

  18. Anthropogenic phosphorus flows under different scenarios for the city of Stockholm, Sweden.

    Science.gov (United States)

    Wu, Jiechen; Franzén, Daniel; Malmström, Maria E

    2016-01-15

    Today, concerns prevail about the unsustainable use of phosphorus and worldwide eutrophication, thus requiring efficient management of phosphorus flows. With increasing population and associated urban growth, urban management of phosphorus flows in the perspectives of recycling, eutrophication and total budget becomes increasingly important. This study mapped phosphorus flows for a reference year (2013) and a future year (2030) using different scenarios for the city of Stockholm, Sweden. The results indicated that the Swedish goal of recycling phosphorus from wastewater would cover the majority of the total phosphorus budget for Stockholm. However, in 2013, only 10% of phosphorus was recycled for agricultural use, around half of which was from sewage sludge and the other half from food waste. Almost 50% of total phosphorus was sent to landfill/mining waste capping with sewage sludge, for economic reasons and lack of market. Among the scenarios of upstream and downstream urban management options studied in combination with population growth, recovery of phosphorus from sewage sludge had the greatest potential to increase the fraction recycled to agriculture. However, only upstream measures, e.g. changed diet, were able to reduce the total phosphorus budget. Urban management of phosphorus flows based on the different perspectives of recycling, eutrophication or total budget was shown to potentially result in different preferred management actions and both upstream and downstream measures need to be considered. Moreover, management needs to pay attention to small but environmentally sensitive flows, particularly when setting city goals on phosphorus recycling by percentage in a large budget. PMID:26442719

  19. Phosphorus poisoning in waterfowl

    Science.gov (United States)

    Coburn, D.R.; DeWitt, J.B.; Derby, J.V., Jr.; Ediger, E.

    1950-01-01

    Black ducks and mallards were found to be highly susceptible to phosphorus poisoning. 3 mg. of white phosphorus per kg. of body weight given in a single dose resulted in death of a black duck in 6 hours. Pathologic changes in both acute and chronic poisoning were studied. Data are presented showing that diagnosis can be made accurately by chemical analysis of stored tissues in cases of phosphorus poisoning.

  20. Environmental Phosphorus Recovery Based on Molecular Bioscavengers

    DEFF Research Database (Denmark)

    Gruber, Mathias Felix

    . Finally, it is shown how computational fluid dynamics can be used to optimize large-scale industrial processes using an open-source model, which we have made freely available online to the membrane community, and the advantages/disadvantages of different potential physical implementations of the proposed......Phosphorus is a ubiquitous element of all known life and as such it is found throughout numerous key molecules related to various cellular functions. The supply of phosphorus is tightly linked to global food security, since phosphorus is used to produce agricultural fertilizers, without which...... characteristic amino acid distributions of the binding sites. Quantum mechanical methods are used to investigate how phosphate moieties are described using electronic structure methods, and molecular dynamics in combination with quantum mechanics are used to show how the dynamical interaction between phosphates...

  1. Glacial atmospheric phosphorus deposition

    Science.gov (United States)

    Kjær, Helle Astrid; Dallmayr, Remi; Gabrieli, Jacopo; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Svensson, Anders; Vallelonga, Paul

    2016-04-01

    Phosphorus in the atmosphere is poorly studied and thus not much is known about atmospheric phosphorus and phosphate transport and deposition changes over time, though it is well known that phosphorus can be a source of long-range nutrient transport, e.g. Saharan dust transported to the tropical forests of Brazil. In glacial times it has been speculated that transport of phosphorus from exposed shelves would increase the ocean productivity by wash out. However whether the exposed shelf would also increase the atmospheric load to more remote places has not been investigated. Polar ice cores offer a unique opportunity to study the atmospheric transport of aerosols on various timescales, from glacial-interglacial periods to recent anthropogenic influences. We have for the first time determined the atmospheric transport of phosphorus to the Arctic by means of ice core analysis. Both total and dissolved reactive phosphorus were measured to investigate current and past atmospheric transport of phosphorus to the Arctic. Results show that glacial cold stadials had increased atmospheric total phosphorus mass loads of 70 times higher than in the past century, while DRP was only increased by a factor of 14. In the recent period we find evidence of a phosphorus increase over the past 50 yrs in ice cores close to human occupation likely correlated to forest fires. References: Kjær, Helle Astrid, et al. "Continuous flow analysis method for determination of dissolved reactive phosphorus in ice cores." Environmental science & technology 47.21 (2013): 12325-12332. Kjær, Helle Astrid, et al. "Greenland ice cores constrain glacial atmospheric fluxes of phosphorus." Journal of Geophysical Research: Atmospheres120.20 (2015).

  2. TEMPORAL AND SPATIAL DISTRIBUTION OF PHOSPHORUS IN THE XIANGXI RIVER

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Phosphorus is an essential and oftenlimiting nutrientin both marine andfreshwater ecosystems,yetits oversup-plyis of concern in many environments due to its role ineutrophication[1].Phosphorus enters rivers from diffusecatchment sources(particularly agriculture)and point(effluent)sources.However,river systems have an im-portant internal capacity to remove or release phosphorusfrom/to the water column and to trans-form phosphorusbetween organic,inorganic,particulate and dissolvedforms.River bed sediments can...

  3. Long-term accumulation and transport of anthropogenic phosphorus in three river basins

    Science.gov (United States)

    Powers, Stephen M.; Bruulsema, Thomas W.; Burt, Tim P.; Chan, Neng Iong; Elser, James J.; Haygarth, Philip M.; Howden, Nicholas J. K.; Jarvie, Helen P.; Lyu, Yang; Peterson, Heidi M.; Sharpley, Andrew N.; Shen, Jianbo; Worrall, Fred; Zhang, Fusuo

    2016-05-01

    Global food production depends on phosphorus. Phosphorus is broadly applied as fertilizer, but excess phosphorus contributes to eutrophication of surface water bodies and coastal ecosystems. Here we present an analysis of phosphorus fluxes in three large river basins, including published data on fertilizer, harvested crops, sewage, food waste and river fluxes. Our analyses reveal that the magnitude of phosphorus accumulation has varied greatly over the past 30-70 years in mixed agricultural-urban landscapes of the Thames Basin, UK, the Yangtze Basin, China, and the rural Maumee Basin, USA. Fluxes of phosphorus in fertilizer, harvested crops, food waste and sewage dominate over the river fluxes. Since the late 1990s, net exports from the Thames and Maumee Basins have exceeded inputs, suggesting net mobilization of the phosphorus pool accumulated in earlier decades. In contrast, the Yangtze Basin has consistently accumulated phosphorus since 1980. Infrastructure modifications such as sewage treatment and dams may explain more recent declines in total phosphorus fluxes from the Thames and Yangtze Rivers. We conclude that human-dominated river basins may undergo a prolonged but finite accumulation phase when phosphorus inputs exceed agricultural demand, and this accumulated phosphorus may continue to mobilize long after inputs decline.

  4. Distribution of phosphorus resources between rich and poor countries: The effect of recycling

    NARCIS (Netherlands)

    Weikard, H.P.; Seyhan, D.

    2009-01-01

    Phosphorus (P) is an essential input into agriculture with no substitute. Thus international and intertemporal P allocations greatly impact food security which requires increased food production for a growing world population. As high quality phosphorus mines are being depleted, recycling gains impo

  5. Modeling and mitigation of denitrification 'woodchip' bioreactor phosphorus releases during treatment of aquaculture wastewater

    Science.gov (United States)

    Denitrification 'woodchip' bioreactors designed to remove nitrate from agricultural waters may either be phosphorus sources or sinks. A 24 d batch test showed woodchip leaching is an important source of phosphorus during bioreactor start-up with a leaching potential of approximately 20 -30 mg P per ...

  6. Modularised process-based modelling of phosphorus loss at farm and catchment scale

    Directory of Open Access Journals (Sweden)

    M. G. Hutchins

    2002-01-01

    Full Text Available In recent years, a co-ordinated programme of data collection has resulted in the collation of sub-hourly time-series of hydrological, sediment and phosphorus loss data, together with soil analysis, cropping and management information for two small ( Keywords: phosphorus, erosion, process-based modelling, agriculture

  7. Organic chemistry of elemental phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Milyukov, V A; Budnikova, Yulia H; Sinyashin, Oleg G [A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre of the Russian Academy of Sciences, Kazan (Russian Federation)

    2005-09-30

    The principal achievements and the modern trends in the development of the chemistry of elemental phosphorus are analysed, described systematically and generalised. The possibilities and advantages of the preparation of organophosphorus compounds directly from white phosphorus are demonstrated. Attention is focused on the activation and transformation of elemental phosphorus in the coordination sphere of transition metal complexes. The mechanisms of the reactions of white phosphorus with nucleophilic and electrophilic reagents are discussed. Electrochemical approaches to the synthesis of organic phosphorus derivatives based on white phosphorus are considered.

  8. Influence of soil phosphorus and manure on phosphorus leaching in Swedish topsoils

    OpenAIRE

    Svanbäck, Annika; Ulen, Barbro; Etana, Ararso; Bergström, Lars; Kleinman, Peter J.A.; Mattsson, Lennart

    2013-01-01

    In Sweden, subsurface transport of phosphorus (P) from agricultural soils represents the primary pathway of concern for surface water quality. However, there are mixed findings linking P in leachate with soil P and limited understanding of the interactive effects of applied P sources and soil test P on P leaching potential. Identifying soils that are susceptible to P leaching when manure is applied is critical to management strategies that reduce P loadings to water bodies. Intact soil column...

  9. Phosphorus flows and balances of the European Union Member States.

    Science.gov (United States)

    van Dijk, Kimo C; Lesschen, Jan Peter; Oenema, Oene

    2016-01-15

    Global society faces serious "phosphorus challenges" given the scarcity, essentiality, unequal global distribution and, at the same time, regional excess of phosphorus (P). Phosphorus flow studies can be used to analyze these challenges, providing insight into how society (re)uses and loses phosphorus, identifying potential solutions. Phosphorus flows were analyzed in detail for EU-27 and its Member States. To quantify food system and non-food flows, country specific data and historical context were considered. The sectors covered were crop production (CP), animal production (AP), food processing (FP), non-food production (NF) and consumption (HC). The results show that the EU-27 imported 2392 Gg P in 2005, half of which accumulated in agricultural soils (924 Gg) and half was lost as waste (1217 Gg). Net accumulation was 4.9 kg P/ha/year ranging between +23.2 (Belgium) and -2.8 (Slovakia). From the system losses, 54% was lost from HC in diverse waste flows and 28% from FP, mainly through incinerated slaughter residues. The largest HC losses (655 Gg) were wastewater (55%), food waste (27%), and pet excreta (11%). Phosphorus recycling rates were 73% in AP, 29% in FP, 21% in HC and ~0% in NF. The phosphorus use efficiencies showed that, relative to sector input, about 70% was taken up by crops (CP), 24% was retained in animals (AP), 52% was contained in food products (FP), 76% was stored in non-food materials (NF), and 21% was recycled (HC). Although wide-ranging variation between countries, generally phosphorus use in EU-27 was characterized by relatively (1) large dependency on (primary) imports, (2) long-term accumulation in agricultural soils, especially in west European countries, (3) leaky losses throughout entire society, especially emissions to the environment and sequestered waste, (4) little recycling with the exception of manure, and (5) low use efficiencies, because of aforementioned issues, providing ample opportunities for improvement. PMID:26421756

  10. Phosphorus Availability in Soils Amended with Wheat Residue Char

    OpenAIRE

    Parvage, Md. Masud; Ulén, Barbro; Eriksson, Jan; Strock, Jeffery; Kirchmann, Holger

    2013-01-01

    Plant availability and risk for leaching and/or runoff losses of phosphorus (P) from soils depends among others on P concentration in the soil solution. Water soluble P in soil measures soil solution P concentration. The aim of this study was to understand the effect of wheat residue char (biochar) addition on water soluble P concentration in a wide range of biochar amended soils. Eleven agricultural fields representing dominant soil texture classes of Swedish agricultural lands were chosen. ...

  11. Scientific Opinion on the use of animal-based measures to assess welfare in pigs

    DEFF Research Database (Denmark)

    Broom, D.; Doherr, M.G.; Edwards, S.;

    2013-01-01

    but not those where time limitation prevents it. There are currently insufficient animal-based measures to use as welfare outcome indicators on-farm or in the slaughterhouse to assess the issues of pain, frustration and other positive and negative emotional states. The extent to which short-term management can...... prevent the negative effects of hazards arising from genetic selection, and of most housing-related problems, is extremely limited. Herd monitoring and surveillance programmes should be implemented within the pig industry using a range of appropriate animal-based measures to document welfare changes over......Animal-based measures, identified on the basis of scientific evidence, can be used effectively in the evaluation of the welfare of on-farm pigs in relation to laws, codes of practice, quality assurance schemes and management. Some of these measures are also appropriate for ante-mortem inspection...

  12. phosphorus retention data and metadata

    Data.gov (United States)

    U.S. Environmental Protection Agency — phosphorus retention in wetlands data and metadata This dataset is associated with the following publication: Lane , C., and B. Autrey. Phosphorus retention of...

  13. Phosphorus recycling and food security in the long run

    NARCIS (Netherlands)

    Weikard, Hans Peter

    2016-01-01

    Food security for all is a global political goal and an outstanding moral concern. The common response to this concern is agricultural intensification, which includes among other things increasing inputs of fertilisers. The paper addresses the fact that phosphorus (P) is essential for agricultura

  14. Does balanced phosphorus fertilisation sustain high herbage yields and phosphorus contents in alternately grazed and mown pastures?

    NARCIS (Netherlands)

    Middelkoop, van J.C.; Salm, van der C.; Ehlert, P.A.I.; Boer, de I.J.M.; Oenema, O.

    2016-01-01

    Many soils of agricultural land in affluent countries have been enriched with phosphorus (P), because P application via fertilisers and manures was larger than P withdrawal via harvested biomass. This practice threatens the long-term availability of P fertilisers derived from finite rock phosphat

  15. Impacts of anthropic pressures on soil phosphorus availability, concentration, and phosphorus forms in sediments in a Southern Brazilian watershed

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, Joao Batista Rossetto; Rheinheimer dos Santos, Danilo; Goncalves, Celso Santos; Copetti, Andre Carlos Cruz [Dept. de Solos, Univ. Federal de Santa Maria, Centro de Ciencias Rurais, Santa Maria, RS (Brazil); Bortoluzzi, Edson Campanhola [Faculdade de Agronomia e Medicina Veterinaria da Univ. de Passo Fundo, RS (Brazil); Tessier, Daniel [Inst. National de la Recherche Agronomique, Versailles (France)

    2010-04-15

    Purpose: The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosphorus forms in soil sediments as contaminant agents of waters as a function of anthropic pressures. Materials and methods On three subwatersheds with different anthropic pressure, water and sediment samples were collected automatically in upstream and downstream discharge points in six rainfall events during the tobacco growing season. Phosphorus desorption capacity from soil sediments was estimated by successive extractions with anion exchange resins. First-order kinetic models were adjusted to desorption curves for estimating potentially bioavailable particulate phosphorus, desorption rate constant, and bioavailable particulate phosphorus. Results and discussion The amount of bioavailable particulate phosphorus was directly correlated with the iron oxide content. The value of desorption rate constant was directly related with the total organic carbon and inversely with the iron oxide contents. Phosphate ions were released to solution, on average, twice as rapidly from sediments collected in subwatersheds with low anthropic activity than from those ones of highly anthropic subwatersheds. Anthropic pressure on watershed can engender high sediment discharge, but these solid particles seem to present low phosphorus-releasing capacity to water during transport due to the evidenced high affinity between phosphorus and iron oxide from sediments. Conclusions Anthropic pressure was related with sediment concentration and phosphorus release to aquatic systems. While natural vegetation along streams plays a role on soil and water depuration, it is unable to eliminate the phosphorus inputs intrinsic to the agricultural-intensive systems. Recommendations and perspectives The contamination of water in watershed by phosphates is facilitated by the

  16. Phosphorus Deficiency in Ducklins

    Institute of Scientific and Technical Information of China (English)

    CuiHengmin; LuoLingping

    1995-01-01

    20 one-day-old Tianfu ducklings were fed on a natural diet deficient in phosphorus(Ca 0.80%,P 0.366%)for three weeks and examined for signs and lesions.Signs began to appear at the age of one week,and became serous at two weeks.13 ducklings died during the experiment.Morbidity was 100% and mortality was 65%.The affected ducklings mainly showed leg weakness,severe lamencess,deprssion,lack of appetite and stunted growth,The serum alkaline phosphatase activities increased markedly.The serum phosphorus concentration,tibial ash,ash calcium and phosphorus content decreased obviously.At necropsy,maxillae and ribe were soft,and the latter was crooked.Long ones were soft and broke easily.The hypertrophic zone of the growth-plate in the epiphysis of long ones was lengthened and osteoid tissue increased in the metaphyseal spongiosa histopathologically.The above mentioned symptoms and lesions could be prevented by adding phosphorus to the natural deficient diet(up to 0.65%),The relationship between lesions and signs,pathomorphological characterisation and pathogensis were also discussed in this paper.

  17. Animal based parameters are no panacea for on-farm monitoring of animal welfare

    NARCIS (Netherlands)

    Bracke, M.B.M.

    2007-01-01

    On-farm monitoring of animal welfare is an important, present-day objective in animal welfare science. Scientists tend to focus exclusively on animal-based parameters, possibly because using environment-based parameters could be begging the question why welfare has been affected and because animal-b

  18. Standard of reporting animal-based experimental research in Indian Journal of Pharmacology

    Directory of Open Access Journals (Sweden)

    Umme Aiman

    2015-01-01

    Conclusion: Present study demonstrates relatively good reporting standards in animal studies published in IJP. The items which need to be improved are randomization, blinding, sample size calculation, stating the limitations of study, sources of support and conflict of interest. The knowledge shared in the present paper could be used for better reporting of animal based experiments.

  19. Global baseline data on phosphorus pollution of large lakes

    Science.gov (United States)

    Fink, Gabriel; Flörke, Martina; Alcamo, Joseph

    2016-04-01

    Lakes are exposed to harmful eutrophication which is the most concerning water quality issue on global scale. Eutrophication is caused by phosphorous pollution in most lakes. Hence, global consistent base line data on phosphorus loadings are needed to assess future sustainable development. We used the modeling framework WaterGAP3 to calculate present total phosphorus loadings to the world's largest lakes. Estimates of modeled total phosphorus (TP) loadings as well as the contributions of different sectors were successfully validated against measured data. Based on these findings, annual total phosphorus loadings to lakes were calculated for diffuse and point sources according to the different sectors domestic, manufacturing, urban surface runoff, agriculture and background for the time period 1990 to 2010. Our results show high phosphorus loadings into lakes in southern latitudes. On global average, industrial fertilizer is the main anthropogenic source while background loadings are low in comparison. Nevertheless, both features indicate a high potential to reduce the exposure to eutrophication in lakes which are faced with high phosphor inputs. The global average of TP loadings was 7% higher in the time period 2005-2010 than in the period 1990-1995. The global average in 2005-2010 results from an increase in TP loadings of 79% in South America, which was dampened by a decrease in Europe, North America, and Asia. Chinese lakes were exposed to massive increasing phosphorus loadings, too. Both increasing and decreasing trends are caused primarily by changing industrial fertilizer application rates. In conclusion, this study provides a consistent and model based synopsis of global trends and sources of phosphorus loadings to large lakes. The estimates of phosphorus pollution of lakes present a basis for assessing and managing the global eutrophication problem.

  20. Phosphorus losses in simulated rainfall runoff from manured soils of Alberta.

    Science.gov (United States)

    Volf, Callie A; Ontkean, Gerald R; Bennett, D Rodney; Chanasyk, David S; Miller, Jim J

    2007-01-01

    Manure applied to agricultural land at rates that exceed annual crop nutrient requirements can be a source of phosphorus in runoff. Manure incorporation is often recommended to reduce phosphorus losses in runoff. A small plot rainfall simulation study was conducted at three sites in Alberta to evaluate the effects of manure rate and incorporation on phosphorus losses. Treatments consisted of three solid beef cattle manure application rates (50, 100, and 200 kg ha(-1) total phosphorus), an unmanured control, and two incorporation methods (nonincorporated and incorporated with one pass of a double disk). Simulated rain was applied to soils with freshly applied and residual (1 yr after application) manure at 70 mm h(-1) to produce 30 min of runoff. Soil test phosphorus (STP), total phosphorus (TP), and dissolved reactive phosphorus (DRP) concentrations in runoff increased with manure rate for fresh and residual manure. Initial abstraction and runoff volumes did not change with manure rate. Initial abstraction, runoff volumes, and phosphorus concentrations did not change with manure incorporation at Lacombe and Wilson, but initial abstraction volumes increased and runoff volumes and phosphorus concentrations decreased with incorporation of fresh manure at Beaverlodge. Phosphorus losses in runoff were directly related to phosphorus additions. Extraction coefficients (slopes of the regression lines) for the linear relationships between residual manure STP and phosphorus in runoff were 0.007 to 0.015 for runoff TP and 0.006 to 0.013 for runoff DRP. While incorporation of manure with a double disk had no significant effect on phosphorus losses in runoff from manure-amended soils 1 yr after application, incorporation of manure is still recommended to control nitrogen losses, improve crop nutrient uptake, and potentially reduce odor concerns.

  1. Sustainable Phosphorus Measures: Strategies and Technologies for Achieving Phosphorus Security

    OpenAIRE

    Stuart White; Dana Cordell

    2013-01-01

    Phosphorus underpins the world’s food systems by ensuring soil fertility, maximising crop yields, supporting farmer livelihoods and ultimately food security. Yet increasing concerns around long-term availability and accessibility of the world’s main source of phosphorus—phosphate rock, means there is a need to investigate sustainable measures to buffer the world’s food systems against the long and short-term impacts of global phosphorus scarcity. While the timeline of phosphorus scarcity is c...

  2. Phosphorus in prebiotic chemistry

    OpenAIRE

    Schwartz, Alan W

    2006-01-01

    The prebiotic synthesis of phosphorus-containing compounds—such as nucleotides and polynucleotides—would require both a geologically plausible source of the element and pathways for its incorporation into chemical systems on the primitive Earth. The mineral apatite, which is the only significant source of phosphate on Earth, has long been thought to be problematical in this respect due to its low solubility and reactivity. However, in the last decade or so, at least two pathways have been dem...

  3. Characterization and sonochemical synthesis of black phosphorus from red phosphorus

    Science.gov (United States)

    Aldave, Sandra H.; Yogeesh, Maruthi N.; Zhu, Weinan; Kim, Joonseok; Sonde, Sushant S.; Nayak, Avinash P.; Akinwande, Deji

    2016-03-01

    Phosphorene is a new two-dimensional material which is commonly prepared by exfoliation from black phosphorus bulk crystals that historically have been synthesized from white phosphorus under high-pressure conditions. The few layers of phosphorene have a direct band gap in the range of 0.3-2 eV and high mobility at room temperature comparable to epitaxial graphene. These characteristics can be used for the design of high speed digital circuits, radio frequency circuits, flexible and printed systems, and optoelectronic devices. In this work, we synthesized black phosphorus from red phosphorus, which is a safer solid precursor, using sonochemistry. Furthermore, via a variety of microscopy and spectroscopy techniques, we report characterization results of the sonochemically synthesized black phosphorus in addition to the commercial black phosphorus. Finally, we describe the air stability of black phosphors and the crystalline structure of the synthesized material. This is the first result of sonochemical or solution-based synthesis of black phosphorus based on readily available low-cost red phosphorus. This solution-based synthesis of black phosphorus is suitable for printable applications of nanomaterial.

  4. Variation in phosphorus acquisition efficiency among maize varieties as related to mycorrhizal functioning

    NARCIS (Netherlands)

    Wang, X.X.

    2016-01-01

    Phosphorus (P) is a main limiting factor for agricultural production, but overusing P fertilizer has brought serious environmental damages in China. Improving P acquisition efficiency of agricultural crops is an urgent topic. It has been proven repeatedly that arbuscular mycorrhizal fungi (AMF) and

  5. Spatio-Temporal Story Mapping Animation Based On Structured Causal Relationships Of Historical Events

    Science.gov (United States)

    Inoue, Y.; Tsuruoka, K.; Arikawa, M.

    2014-04-01

    In this paper, we proposed a user interface that displays visual animations on geographic maps and timelines for depicting historical stories by representing causal relationships among events for time series. We have been developing an experimental software system for the spatial-temporal visualization of historical stories for tablet computers. Our proposed system makes people effectively learn historical stories using visual animations based on hierarchical structures of different scale timelines and maps.

  6. Phosphorus absorption by of corn hybrids grown in savana soils

    International Nuclear Information System (INIS)

    In the past years the savana region has been one of the main agricultural expansion areas, however their soils present high limitation for plant growth due their high acidity, low natural fertility, and low phosphorus availability. The objective of this work was to compare 30 of the main recommended maize (Zea mays L.) hybrids for the cerrado region in relation to their ability to absorb poorly-available soil phosphorus through the 32P isotopic dilution technique, using a Typic Dystrarox cultivated for 20 years and another under natural vegetation. Differences in absorption ability were observed among hybrids, seven classified as efficient, sixteen mildly efficient and seven inefficient, for the case of soil cultivated for 20 years. The plant growth and phosphorus concentration in the natural soil was lower due to its low fertility. (author)

  7. Phosphorus recovery from municipal solid waste incineration fly ash.

    Science.gov (United States)

    Kalmykova, Yuliya; Fedje, K Karlfeldt

    2013-06-01

    The potential of phosphorus (P) recycling from municipal solid waste incineration (MSWI) residue is investigated. Vast and ever increasing amounts of incineration residues are produced worldwide; these are an environmental burden, but also a resource, as they are a major sink for the material flows of society. Due to strict environmental regulations, in combination with decreasing landfilling space, the disposal of the MSWI residues is problematic. At the same time, resource scarcity is recognized as a global challenge for the modern world, and even more so for future generations. This paper reports on the methods and efficiency of P extraction from MSWI fly ash by acid and base leaching and precipitation procedures. Phosphorus extracted from the MSWI residues generated each year could meet 30% of the annual demand for mineral phosphorus fertiliser in Sweden, given a recovery rate of 70% achieved in this initial test. The phosphorus content of the obtained product is slightly higher than in sewage sludge, but due to the trace metal content it is not acceptable for application to agricultural land in Sweden, whereas application in the rest of the EU would be possible. However, it would be preferable to use the product as a raw material to replace rock phosphate in fertilizer production. Further development is currently underway in relation to procedure optimization, purification of the phosphorus product, and the simultaneous recovery of other resources. PMID:23490361

  8. Phosphorus and emerging micro-pollutants in surface waters: challenges and prospects for water quality improvement

    OpenAIRE

    Hooda, Peter S.; Wilkinson Jr, John; Millier, Helen

    2014-01-01

    An oversupply of Phosphorus in water bodies accelerates growth of algae and higher forms of plant life to produce undesirable impacts on overall water quality. Phosphorus inputs to surface waters arise from a variety of point and nonpoint sources. However much of the P is contributed by agricultural runoff and outfall of treated (or untreated) wastewater in receiving water-bodies. Point sourced-P inputs to waters have considerably decreased in recent years, at least partly drive...

  9. PHOSPHORUS REMOVAL USING STEEL SLAG

    Institute of Scientific and Technical Information of China (English)

    Y.Z. Lan; S. Zhang; J.K. Wang; R. W. Smith

    2006-01-01

    Steel slag is a byproduct produced in large amounts in the steel-making process. It is an important resource that can be effectively utilized. An experiment was described in which steel slag was tested as an adsorbent for the removal of phosphorus from waste water. Phosphorus removal depended on the amount of steel slag added, the pH value, the contact time, and the initial concentration. Under laboratory conditions when the added slag was 7.5g/L, the contact time 2h, and the pH value was equivalent to 6.5, over 99% of the phosphorus was removed; the experimental data on steel slag adsorption of phosphorus in the water fitted the Freundlich isotherm model. Steel slag was found to be very effective in adsorbing phosphorus.

  10. The Skeletal Muscle Anabolic Response to Plant- versus Animal-Based Protein Consumption.

    Science.gov (United States)

    van Vliet, Stephan; Burd, Nicholas A; van Loon, Luc J C

    2015-09-01

    Clinical and consumer market interest is increasingly directed toward the use of plant-based proteins as dietary components aimed at preserving or increasing skeletal muscle mass. However, recent evidence suggests that the ingestion of the plant-based proteins in soy and wheat results in a lower muscle protein synthetic response when compared with several animal-based proteins. The possible lower anabolic properties of plant-based protein sources may be attributed to the lower digestibility of plant-based sources, in addition to greater splanchnic extraction and subsequent urea synthesis of plant protein-derived amino acids compared with animal-based proteins. The latter may be related to the relative lack of specific essential amino acids in plant- as opposed to animal-based proteins. Furthermore, most plant proteins have a relatively low leucine content, which may further reduce their anabolic properties when compared with animal proteins. However, few studies have actually assessed the postprandial muscle protein synthetic response to the ingestion of plant proteins, with soy and wheat protein being the primary sources studied. Despite the proposed lower anabolic properties of plant vs. animal proteins, various strategies may be applied to augment the anabolic properties of plant proteins. These may include the following: 1) fortification of plant-based protein sources with the amino acids methionine, lysine, and/or leucine; 2) selective breeding of plant sources to improve amino acid profiles; 3) consumption of greater amounts of plant-based protein sources; or 4) ingesting multiple protein sources to provide a more balanced amino acid profile. However, the efficacy of such dietary strategies on postprandial muscle protein synthesis remains to be studied. Future research comparing the anabolic properties of a variety of plant-based proteins should define the preferred protein sources to be used in nutritional interventions to support skeletal muscle mass gain

  11. Scientific Opinion on the use of animal-based measures to assess welfare of broilers

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Animal Health and Welfare

    2012-07-01

    Full Text Available

    Animal-based measures (ABM can be used effectively in the on-farm evaluation of broiler welfare in relation to laws, codes of practice, quality assurance schemes, management and also partly for ante-mortem inspection. Some ABM can also be taken post-mortem at the slaughterhouse. Non-animal-based measures can be used when the association between them and the welfare outcome is strong and when they are more efficient than ABM as a means to safeguard welfare. They can also be useful predictors of welfare in broilers. The choice of animal-based measures will depend upon the specific objectives of the assessment. The full list is comparable to a ‘toolbox’, from which the appropriate set of measures can be selected. The Welfare Quality® protocol provides information on the majority of the welfare outcomes for the main factors identified in the EFSA Scientific Opinions but not those where time limitation prevents it. There is a lack of research on the use of ABM on-farm and in the slaughterhouse to assess pain, frustration, boredom and other negative or positive emotional states in the standard broiler. There are limited management options to prevent poor welfare when the flock is still in the house e.g. to improve the ventilation system. The same applies to negative consequences arising from genetic selection. There is a need for more systematic flock monitoring and surveillance programmes in the broiler industry. Visual inspection has a very high potential to improve animal welfare in broiler production when a range of appropriate ABM is used in the slaughterhouse. Benchmarking can be used to document welfare changes over time, including automatic monitoring and assessment systems. Attention should also be paid to initial and ongoing training of assessors in the field and in the abattoir to ensure valid and robust measurements.

  12. Phosphorus in agroecosystems on gray forest soils in the opolie regions of Central Russia

    Science.gov (United States)

    Nikitishen, V. I.; Lichko, V. I.; Kurganova, E. V.

    2008-08-01

    Long-term stationary field experiments revealed a poor supply of gray forest soils with available phosphorus, which provides no more than half the amount necessary for optimum nutrition of plants. It was found that agricultural crops with different capacities to assimilate phosphates from the soil and fertilizers have strong requirements for phosphorus fertilizers and abruptly increase their utilization in the production process with increasing level of nitrogen nutrition. Crops with the optimum level of nitrogen nutrition uptake a double amount of phosphorus compared to crops depleted in nitrogen. Clover and barley have an increased capacity to mobilize soil phosphates from the lower horizons at an extremely low content of available forms of them in the plow layer. Winter wheat and corn are characterized by an active uptake of phosphorus applied with fertilizer and its efficient utilization in the production process if the nitrogen supply is not a limiting factor. The level of phosphorus nutrition of subsequent rotation crops increases due to the enrichment of the root-inhabited soil layer with phosphorus from clover root and harvest residues. Based on the data about the unacceptably abrupt decrease in the application of mineral fertilizers in Russian agriculture (90% of fertilizers are exported now), it is shown that the export of fertilizers should be limited at the state level, because chemicals, and primarily phosphorus fertilizers, should be considered strategic resources for internal use only.

  13. Agricultural Production.

    Science.gov (United States)

    Lehigh County Area Vocational-Technical School, Schnecksville, PA.

    This brochure describes the philosophy and scope of a secondary-level course in agricultural production. Addressed in the individual units of the course are the following topics: careers in agriculture and agribusiness, animal science and livestock production, agronomy, agricultural mechanics, supervised occupational experience programs, and the…

  14. The Optimum Mesophilic Temperature of Batch Process Biogas Production from Animal-based Wastes

    Directory of Open Access Journals (Sweden)

    Osita Obineche Obiukwu

    2014-10-01

    Full Text Available The optimum mesophilic temperature of biogas production from blends The optimum temperature of biogas production from blends of animal-based wastes was determined under controlled heat supply to the digester in a batch digestion process. Cow Dung (CD and Poultry Droppings (PD were blended in the ratio of CD: PD: 1:3. The digester was operated at average ambient temperature of 30°C as baseline. Biogas production from the waste blends was monitored under the temperatures of 32 to 45°C. Results obtained indicate maximum cumulative gas yield was observed at the temperature of 40°C. The 40°C temperature gave the highest biogas yield of 2685 mL followed by the 35°C temperature with the cumulative yield of 2535 mL. The ambient temperature of 30°C had the least cumulative biogas yield of 185 mL. These results indicate that increased and steady biogas production can be achieved under the optimum mesophilic temperature of 40°C when these animal-based wastes are digested in batch digestion process.

  15. Effect of Land Application of Phosphorus-Saturated Gypsum on Soil Phosphorus in a Laboratory Incubation

    Directory of Open Access Journals (Sweden)

    Karen L. Grubb

    2012-01-01

    Full Text Available Agricultural drainage ditches can deliver high loads of phosphorus (P to surface water. Installation of filter structures containing P sorbing materials (PSMs, including gypsum, is an emerging practice that has shown promise to reduce these P loads. The objective of this study was to evaluate what effect soil amendment with gypsum would have on soil P concentrations and forms in a laboratory incubation experiment. Gypsum was saturated at two levels with P, and applied to a silt loam and a sandy loam at two rates. The treated soils were incubated in the laboratory at 25°C, and samples were collected on eight dates between 0 and 183 days after amendment. Spent gypsum application did not significantly increase soil water-extractable or Mehlich 3 P when applied at typical agronomic rates. This appears to be a viable strategy to remove P from agricultural drainage waters but does not appear to provide any additional P fertilizer value.

  16. Agricultural Waste.

    Science.gov (United States)

    Xue, Ling; Zhang, Panpan; Shu, Huajie; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2016-10-01

    In recent years, the quantity of agricultural waste has been rising rapidly all over the world. As a result, the environmental problems and negative impacts of agricultural waste are drawn more and more attention. Therefore, there is a need to adopt proper approaches to reduce and reuse agricultural waste. This review presented about 200 literatures published in 2015 relating to the topic of agricultural waste. The review examined research on agricultural waste in 2015 from the following four aspects: the characterization, reuse, treatment, and management. Researchers highlighted the importance to reuse agricultural waste and investigated the potential to utilize it as biofertilizers, cultivation material, soil amendments, adsorbent, material, energy recycling, enzyme and catalyst etc. The treatment of agricultural waste included carbonization, biodegradation, composting hydrolysis and pyrolysis. Moreover, this review analyzed the differences of the research progress in 2015 from 2014. It may help to reveal the new findings and new trends in this field in 2015 comparing to 2014. PMID:27620093

  17. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices. PMID:27263015

  18. Methylotrophic bacteria in sustainable agriculture.

    Science.gov (United States)

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

  19. Prebiotic phosphorus chemistry reconsidered

    Science.gov (United States)

    Schwartz, A. W.; Orgel, L. E. (Principal Investigator)

    1997-01-01

    The available evidence indicates that the origin of life on Earth certainly occurred earlier than 3.5 billion years ago and perhaps substantially earlier. The time available for the chemical evolution which must have preceded this event is more difficult to estimate. Both endogenic and exogenic contributions to chemical evolution have been considered; i.e., from chemical reactions in a primitive atmosphere, or by introduction in the interiors of comets and/or meteorites. It is argued, however, that the phosphorus chemistry of Earth's earliest hydrosphere, whether primarily exogenic or endogenic in origin, was most likely dominated by compounds less oxidized than phosphoric acid and its esters. A scenario is presented for the early production of a suite of reactive phosphonic acid derivatives, the properties of which may have foreshadowed the later appearance of biophosphates.

  20. Electric Conductivity of Phosphorus Nanowires

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-Xiang; LI Hui; ZHANG Xue-Qing; LIEW Kim-Meow

    2009-01-01

    We present the structures and electrical transport properties of nanowires made from different strands of phosphorus chains encapsulated in carbon nanotubes. Optimized by density function theory, our results indicate that the conductance spectra reveal an oscillation dependence on the size of wires. It can be seen from the density of states and current-voltage curves that the structure of nanowires affects their properties greatly. Among them,the DNA-like double-helical phosphorus nanowire exhibits the distinct characteristic of an approximately linear I - V relationship and has a higher conductance than others. The transport properties of phosphorus nanowires are highly correlated with their microstructures.

  1. Phosphorus Accumulating Organisms and Biogeochemical Hotspots

    Science.gov (United States)

    Archibald, J.; Walter, M. T.

    2008-12-01

    Despite extensive research, many of the processes that control phosphorus (P) movement from agricultural fields to streams and lakes are not well understood. This limits our ability to develop management strategies that will mediate P contamination of freshwater ecosystems and subsequent eutrophication. Recent advances in molecular microbiology have prompted a paradigm shift in wastewater treatment that recognizes and exploits the ways specific microbial processes influence P solubility. Central to this enhanced biological phosphorus removal in wastewater treatment plants is a relatively recently discovered microorganism, Candidatus accumulibacter, which takes-up P and stores it internally as polyphosphate under alternating aerobic and anaerobic conditions. Within the past few months we have discovered this organism in the natural environment and its role in P biogeochemistry is unclear. We speculate that it may function similarly in variable source areas, which experience cycles of saturation and desaturation, as it does in the anaerobic- aerobic cycles in a wastewater treatment plant. If so, there may be potential opportunities to realize similarly new perspectives and advancements in the watershed context as have been seen in wastewater technologies. Here we present some of our preliminary findings.

  2. Quantitative Relationship Between Land Use and Phosphorus Discharge in Subtropical Hilly Regions of China

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The increase of phosphorus concentration is a crucial factor causing the eutrophication of water body,while land use has an important impact on agricultural non-point sources (NPS) phosphorus discharge. Sevensites controlling the water in four sub-watersheds and the main exit of the Meicun Watershed of XuanchengCounty, Anhui Province, were investigated by dynamic monitoring of stream water and nutrient discharge,integrating interpretation of aerial image and GIS analysis to find out how the land use affects phosphorusloss with stream water in typical agriculture-forest watershed in subtropical China. These monitored sitesare different in structure of land use. Phosphorus concentration of the stream water was analyzed everyweek and at the next day of rainfall. The velocity of flow was measured by kinemometer to calculatethe runoff flux and phosphorus discharge. The results showed that the runoff flux and the discharges ofdissolved phosphorus (DP), particle-associated phosphorus (PAP) and total phosphorus (TP) had significantexponential relationships with the area percentages of forest, pond and paddy field. There existed a significantlinear relationship between the TP and PAP concentrations in stream water and the area percentages of forest,pond and paddy field, and the discharge of PAP was also significantly linearly correlated with the dischargeof suspended soil particles. There was a logarithmic linear relationship between DP and PAP discharges. Thestudy indicated that the adjustment of land use patterns and construction of ecologically sound landscapewould be an important measure to reduce the runoff discharge of phosphorus. The results would be veryuseful in building the best management practices (BMPs) of agricultural watershed in subtropics.

  3. The impact of agricultural soil erosion on biogeochemical cycling

    OpenAIRE

    Quinton, John N.; Govers, Gerard; Van Oost, Kristof; Bardgett, Richard D.

    2010-01-01

    Soils are the main terrestrial reservoir of nutrients, such as nitrogen and phosphorus, and of organic carbon. Synthesizing earlier studies, we find that the mobilization and deposition of agricultural soils can significantly alter nutrient and carbon cycling. Specifically, erosion can result in lateral fluxes of nitrogen and phosphorus that are similar in magnitude to those induced by fertilizer application and crop removal. Furthermore, the translocation and burial of soil reduces decomposi...

  4. Total Phosphorus in Surface Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Excess phosphorus in surface water can result in eutrophication. TOTALP is reported in kilograms/hectare/year. More information about these resources, including the...

  5. Phosphorus application strategies in potato

    OpenAIRE

    Ekelöf, Joakim

    2014-01-01

    Phosphorus (P) is an essential element that plays an important role in carbohydrate metabolism and energy transfer systems in all plants. Sufficient P supply is therefore essential for providing adequate food, fibre and fuel for society. In potato, P deficiency reduces yield and tuber number due to reduced radiation interception by the canopy. Phosphorus is a limited, non-renewable resource. When lost to water bodies, P causes environmental problems such as eutrophication. Potato fields ...

  6. Evaluating the Impact of Legacy P and Agricultural Conservation Practices on Nutrient Loads from the Maumee River Watershed.

    Science.gov (United States)

    Muenich, Rebecca Logsdon; Kalcic, Margaret; Scavia, Donald

    2016-08-01

    The recent resurgence of hypoxia and harmful algal blooms in Lake Erie, driven substantially by phosphorus loads from agriculture, have led the United States and Canada to begin developing plans to meet new phosphorus load targets. To provide insight into which agricultural management options could help reach these targets, we tested alternative agricultural-land-use and land-management scenarios on phosphorus loads to Lake Erie. These scenarios highlight certain constraints on phosphorus load reductions from changes in the Maumee River Watershed (MRW), which contributes roughly half of the phosphorus load to the lake's western basin. We evaluate the effects on phosphorus loads under nutrient management strategies, reduction of fertilizer applications, employing vegetative buffers, and implementing widespread cover crops and alternative cropping changes. Results indicate that even if fertilizer application ceased, it may take years to see desired decreases in phosphorus loads, especially if we experience greater spring precipitation or snowmelt. Scenarios also indicate that widespread conversions to perennial crops that may be used for biofuel production are capable of substantially reducing phosphorus loads. This work demonstrates that a combination of legacy phosphorus, land management, land use, and climate should all be considered when seeking phosphorus-loading solutions. PMID:27322563

  7. A Substance Flow Model for Global Phosphorus

    Science.gov (United States)

    Vaccari, D. A.

    2015-12-01

    A system-based substance flow model (SFM) for phosphorus is developed based on the global phosphorus substance flow analysis (SFA) of Cordell et al (2009). The model is based strictly on mass balance considerations. It predicts the sensitivity of phosphorus consumption to various interventions intended to conserve reserves, as well as interactions among these efforts, allowing a comparison of their impacts on phosphorus demand. The interventions include control of phosphorus losses from soil erosion, food production and food waste, or phosphorus recycling such as from animal manure or human waste.

  8. Bacteria as transporters of phosphorus through soil

    DEFF Research Database (Denmark)

    Glæsner, N.; Bælum, Jacob; Jacobsen, C. S.;

    2016-01-01

    The transport of phosphorus (P) from agricultural land has led to the eutrophication of surface waters worldwide, especially in areas with intensive animal production. In this research, we investigated the role of bacteria in the leaching of P through three agricultural soils with different......RNA genes cell−1. Leaching of bacteria was in the range of 2.5–4.5 × 105 cells ml−1 prior to application of slurry to the three soil textures. After slurry application, leaching increased to 1.1 × 106 cells ml−1 in the loamy sand, 4.9 × 106 cells ml−1 in the sandy loam and 5.0 × 106 cells ml−1 in the loam....... Based on the reported P content of soil bacteria, 0.3–1.8% of the total P leached was present in the bacterial biomass when no slurry was applied, whereas slurry application increased the leaching of P from the bacterial biomass to 3−7.9% of total P leached. Bacterial leaching was related...

  9. Incentive encourages dairy farmers to lessen phosphorus pollution in Chesapeake Bay

    OpenAIRE

    Sutphin, Michael D.

    2007-01-01

    Virginia Tech researchers in the Department of Dairy Science in the College of Agriculture and Life Sciences are using a grant from the U.S. Department of Agriculture's Natural Resource Conservation Service (NRCS) to offer incentive payments to dairy farmers who reduce phosphorus overfeeding on their farms. This outreach program follows almost a decade of research on the dietary nutrient management of dairy cattle in Virginia.

  10. Natural Phosphorus Sources for the Pacific Northwest

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Phosphorus is a naturally occurring element found in all rocks; the amount varies by the type of rock. The amount of phosphorus in sediments is expected to be...

  11. Glyphosate sorption and desorption in soils with distinct phosphorus levels

    International Nuclear Information System (INIS)

    The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with Kh2PO4 at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha-1 of P2O5, which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L-1), with a 14C radioactivity of 0.233 kBq mL-1. Four steps of the desorption procedures withCaCl2 0.01 mol L-1 and one extraction with Mehlich 3 were performed only at one concentration (0.84 mol L-1). Soil samples were afterwards biologically oxidized to establish the radioactive balance. Glyphosate competes with phosphorus for specific sorption sites, but this competition becomes important when phosphorus is present at rates higher than 1,000 mg dm-3. Moreover, a small amount of applied glyphosate was extracted (<10%), and the extraction increased with increasing soil phosphorus content. (author)

  12. Glyphosate sorption and desorption in soils with distinct phosphorus levels

    Directory of Open Access Journals (Sweden)

    Prata Fábio

    2003-01-01

    Full Text Available The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with KH2PO4 at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha-1 of P2O5, which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L-1, with a 14C radioactivity of 0.233 kBq mL-1. Four steps of the desorption procedure with CaCl2 0.01 mol L-1 and one extraction with Mehlich 3 were performed only at one concentration (0.84 mol L-1. Soil samples were afterwards biologically oxidized to establish the radioactive balance. Glyphosate competes with phosphorus for specific sorption sites, but this competition becomes important when phosphorus is present at rates higher than 1,000 mg dm-3. Moreover, a small amount of applied glyphosate was extracted (<10%, and the extraction increased with increasing soil phosphorus content.

  13. Electric Conductivity of Phosphorus Nanowires

    International Nuclear Information System (INIS)

    We present the structures and electrical transport properties of nanowires made from different strands of phosphorus chains encapsulated in carbon nanotubes. Optimized by density function theory, our results indicate that the conductance spectra reveal an oscillation dependence on the size of wires. It can be seen from the density of states and current-voltage curves that the structure of nanowires affects their properties greatly. Among them, the DNA-like double-helical phosphorus nanowire exhibits the distinct characteristic of an approximately linear I – V relationship and has a higher conductance than others. The transport properties of phosphorus nanowires are highly correlated with their microstructures. (condensed matter: structure, mechanical and thermal properties)

  14. Edge phonons in black phosphorus.

    Science.gov (United States)

    Ribeiro, H B; Villegas, C E P; Bahamon, D A; Muraca, D; Castro Neto, A H; de Souza, E A T; Rocha, A R; Pimenta, M A; de Matos, C J S

    2016-01-01

    Black phosphorus has recently emerged as a new layered crystal that, due to its peculiar and anisotropic crystalline and electronic band structures, may have important applications in electronics, optoelectronics and photonics. Despite the fact that the edges of layered crystals host a range of singular properties whose characterization and exploitation are of utmost importance for device development, the edges of black phosphorus remain poorly characterized. In this work, the atomic structure and behaviour of phonons near different black phosphorus edges are experimentally and theoretically studied using Raman spectroscopy and density functional theory calculations. Polarized Raman results show the appearance of new modes at the edges of the sample, and their spectra depend on the atomic structure of the edges (zigzag or armchair). Theoretical simulations confirm that the new modes are due to edge phonon states that are forbidden in the bulk, and originated from the lattice termination rearrangements. PMID:27412813

  15. Distributed and dynamic modelling of hydrology, phosphorus and ecology in the Hampshire Avon and Blashford Lakes: evaluating alternative strategies to meet WFD standards.

    Science.gov (United States)

    Whitehead, P G; Jin, L; Crossman, J; Comber, S; Johnes, P J; Daldorph, P; Flynn, N; Collins, A L; Butterfield, D; Mistry, R; Bardon, R; Pope, L; Willows, R

    2014-05-15

    The issues of diffuse and point source phosphorus (P) pollution in the Hampshire Avon and Blashford Lakes are explored using a catchment model of the river system. A multibranch, process based, dynamic water quality model (INCA-P) has been applied to the whole river system to simulate water fluxes, total phosphorus (TP) and soluble reactive phosphorus (SRP) concentrations and ecology. The model has been used to assess impacts of both agricultural runoff and point sources from waste water treatment plants (WWTPs) on water quality. The results show that agriculture contributes approximately 40% of the phosphorus load and point sources the other 60% of the load in this catchment. A set of scenarios have been investigated to assess the impacts of alternative phosphorus reduction strategies and it is shown that a combined strategy of agricultural phosphorus reduction through either fertiliser reductions or better phosphorus management together with improved treatment at WWTPs would reduce the SRP concentrations in the river to acceptable levels to meet the EU Water Framework Directive (WFD) requirements. A seasonal strategy for WWTP phosphorus reductions would achieve significant benefits at reduced cost.

  16. Utilization of radioisotopes in the agriculture

    International Nuclear Information System (INIS)

    Some aspects of radioisotopes utilization in the agriculture, such as, the use of gamma radiation for genetic improvement of plants; the use of C14 as tracer for comprehension of the vegetable physiology; the use of nitrogen and phosphorus isotopes in soil fertilization and plant nutrition; the use of radiation for inset sterelization and, measurement of the humidity and density of soils by neutron moderation and attenuation of gamma radiation, are presented. (M.C.K.)

  17. Modelling climate change, land-use change and phosphorus reduction impacts on phytoplankton in the River Thames (UK)

    Science.gov (United States)

    Bussi, Gianbattista; Whitehead, Paul; Dadson, Simon

    2016-04-01

    In this study, we assess the impact of changes in precipitation and temperature on the phytoplankton concentration of the River Thames (UK) by means of a physically-based model. A scenario-neutral approach was employed to evaluate the effects of climate variability on flow, phosphorus concentration and phytoplankton concentration. In particular, the impact of uniform changes in precipitation and temperature on five groups of phytoplankton (diatoms and large chlorophytes, other chlorophytes, picoalgae, Microcystis-like cyanobacteria and other cyanobacteria) was assessed under three different land-use/land-management scenarios (1 - current land use and phosphorus reduction practices; 2 - expansion of agricultural land and current phosphorus reduction practices; 3 - expansion of agricultural land and optimal phosphorus reduction practices). The model results were assessed within the framework of future climate projections, using the UK Climate Projections 09 (UKCP09) for the 2030s. The results of the model demonstrate that an increase in average phytoplankton concentration due to climate change is highly likely to occur, and its magnitude varies depending on the river reach. Cyanobacteria show significant increases under future climate change and land-use change. An expansion of intensive agriculture accentuates the growth in phytoplankton, especially in the upper reaches of the River Thames. However, an optimal phosphorus removal mitigation strategy, which combines reduction of fertiliser application and phosphorus removal from wastewater, can help to reduce this increase in phytoplankton concentration, and in some cases, compensate for the effect of rising temperature.

  18. Performance of an animal-based test of thirst in commercial broiler chicken farms.

    Science.gov (United States)

    Vanderhasselt, R F; Goethals, K; Buijs, S; Federici, J F; Sans, E C O; Molento, C F M; Duchateau, L; Tuyttens, F A M

    2014-06-01

    Animal-based measures of thirst are currently absent from animal welfare monitoring schemes due to the lack of a well-validated indicator applicable for on-farm use. In the present study, an on-farm test based on voluntary water consumption from an unfamiliar open drinker was validated in a (semi-)commercial setting. To investigate the effect of thirst on water consumption, we subjected 4 flocks of 1,500 broilers to either 0 or 12 h of water deprivation and subsequently measured the amount of water that small subgroups consumed after the deprivation period (first experiment). Broilers that were water deprived before the test drank more than control broilers (P Brazil. After a pretreatment water consumption test, the birds were subjected to 0 or 6 h of water deprivation, and a posttreatment water consumption test was conducted. Only in Brazil, deprived birds drank significantly more than controls in the posttreatment water consumption test (P Brazil than in Belgium (P Brazil, but not in Belgium. These results indicate that the water consumption test is sufficiently sensitive to discriminate between control and 12 h deprived flocks, and in Brazil even between control and 6 h deprived birds. The location of the test within the house did not affect the amount of water consumed in either experiment, suggesting that this variable does not have to be standardized. However, the amount of water consumed by broilers able to drink freely for a long period depended on indoor climatic variables (in Brazil only) and possibly genotype. This suggests that these variables need to be considered when interpreting the test outcome in terms of the thirst level experienced by the broilers.

  19. Dynamic phosphorus budget for lake-watershed ecosystems

    Institute of Scientific and Technical Information of China (English)

    LIU Yong; GUO Huai-cheng; WANG Li-jing; DAI Yong-li; ZHANG Xiu-min; LI Zi-hai; HE Bin

    2006-01-01

    Lake eutrophication caused by excess phosphorus (P) loading from point sources (PS) and nonpoint sources (NPS) is a persistent and serious ecological problem in China. A phosphorus budget, based on material flow analysis(MFA) and system dynamic(SD), is proposed and applied for the agriculture-dominated Qionghai Lake watershed located in southwestern China. The MFA-SD approach will not only cover the transporting process of P in the lake-watershed ecosystems, but also can deal with the changes of P budget due to the dynamics of watershed. P inflows include the fertilizer for agricultural croplands, soil losses, domestic sewage discharges, and the atmospheric disposition such as precipitation and dust sinking. Outflows are consisted of hydrologic export, water resources development, fishery and aquatic plants harvesting. The internal P recycling processes are also considered in this paper.From 1988 to 2015, the total P inflows for Lake Qionghai are in a rapid increase from 35.65 to 78.73 t/a, which results in the rising of P concentration in the lake. Among the total P load 2015, agricultural loss and domestic sewage account for 70.60% and 17.27%respectively, directly related to the rapid social-economic development and the swift urbanization. Future management programs designed to reduce P inputs must be put into practices in the coming years to ensure the ecosystem health in the watershed.

  20. Agricultural methanization

    International Nuclear Information System (INIS)

    After having briefly outlined the interest of the development of methanization of agricultural by-products in the context of struggle against climate change, and noticed that France is only now developing this sector as some other countries already did, this publication describes the methanization process also called anaerobic digestion, which produces a digestate and biogas. Advantages for the agriculture sector are outlined, as well as drawbacks and recommendations (required specific technical abilities, an attention to the use of energetic crops, an improved economic balance which still depends on public subsidies, competition in the field of waste processing). Actions undertaken by the ADEME are briefly evoked

  1. Coral skeletons provide historical evidence of phosphorus runoff on the great barrier reef.

    Directory of Open Access Journals (Sweden)

    Jennie Mallela

    Full Text Available Recently, the inshore reefs of the Great Barrier Reef have declined rapidly because of deteriorating water quality. Increased catchment runoff is one potential culprit. The impacts of land-use on coral growth and reef health however are largely circumstantial due to limited long-term data on water quality and reef health. Here we use a 60 year coral core record to show that phosphorus contained in the skeletons (P/Ca of long-lived, near-shore Porites corals on the Great Barrier Reef correlates with annual records of fertiliser application and particulate phosphorus loads in the adjacent catchment. Skeletal P/Ca also correlates with Ba/Ca, a proxy for fluvial sediment loading, again linking near-shore phosphorus records with river runoff. Coral core records suggest that phosphorus levels increased 8 fold between 1949 and 2008 with the greatest levels coinciding with periods of high fertiliser-phosphorus use. Periods of high P/Ca correspond with intense agricultural activity and increased fertiliser application in the river catchment following agricultural expansion and replanting after cyclone damage. Our results demonstrate how coral P/Ca records can be used to assess terrestrial nutrient loading of vulnerable near-shore reefs.

  2. [Simulation of nitrogen and phosphorus loss in Siling Reservoir watershed with AnnAGNPS].

    Science.gov (United States)

    Bian, Jin-yun; Wang, Fei-er; Yang, Jia; Yu, Jie; Lou, Li-ping; Yu, Dan-ping

    2012-08-01

    By using annual agricultural non-point source model (AnnAGNPS), this study simulated the export loading of nitrogen and phosphorus in Siling Reservoir watershed in Tiaoxi Basin, and integrated with the simulation results, the spatial distribution characteristics of non-point source pollution in the watershed was analyzed. The result showed that the export loading of nitrogen and phosphorus had similar characteristics: in the study area, the export loading of nutrients were higher in southern and western regions and lower in northern and eastern regions. Forest land mainly made up of bamboo was the main export source of nitrogen and phosphorus loading with the contribution above 90% of nutrient load of whole watershed. Three fertilization practices such as no fertilizer (CK), site-specific nutrient management (SSNM) and farmers' fertilizaction practice (FFP) were used in the scenario analysis. The scenario analysis showed that to a certain degree, SSNM could reduce the nitrogen and phosphorus loss. Comparing with FFP, the reduction of SSNM in dissolved nitrogen (DN), particle nitrogen (PN), dissolved phosphorus (DP) and particle phosphorus (PP) was 8.17%, 4.33%, 9.08% and 1.02%, respectively. PMID:23213887

  3. AGRICULTURAL EDUCATION.

    Science.gov (United States)

    STEVENS, GLENN Z.

    FEDERAL LEGISLATION HAS PROVIDED FOR PUBLIC PROGRAMS OF OCCUPATIONAL AGRICULTURE EDUCATION IN LAND GRANT COLLEGES AND UNIVERSITIES, LOCAL SCHOOL DISTRICTS, AND MANPOWER DEVELOPMENT PROGRAMS. PROGRAM OBJECTIVES SHOULD BE TO DEVELOP KNOWLEDGE AND SKILLS, PROVIDE OCCUPATIONAL GUIDANCE AND PLACEMENT, AND DEVELOP ABILITIES IN HUMAN RELATIONS AND…

  4. Screening of inbred popcorn lines for tolerance to low phosphorus.

    Science.gov (United States)

    Santos, O J A P; Gonçalves, L S A; Scapim, C A; S M de Sousa, de; Castro, C R; Y Baba, V; de Oliveira, A L M

    2016-01-01

    Increasing phosphorus use efficiency in agriculture is essential for sustainable food production. Thus, the aims of this study were: i) to identify phosphorus use efficiency (PUE) in popcorn lines during the early plant stages, ii) to study the relationship between traits correlated with PUE, and iii) to analyze genetic diversity among lines. To accomplish this, 35 popcorn lines from Universidade Estadual de Maringá breeding program were studied. The experiment was conducted in a growth chamber using a nutrient solution containing two concentrations of phosphorus (P): 2.5 μM or low P (LP) and 250 μM or high P (HP). After 13 days in the nutrient solution, root morphology traits, shoot and root dry weight, and P content of the maize seedlings were measured. A deviance analysis showed there was a high level of genetic variability. An unweighted pair group method with arithmetic mean (UPGMA) clustering analysis identified three groups for the LP treatment (efficient, intermediate, and inefficient) and three groups for the HP treatment (responsive, moderately responsive, and unresponsive). The results of a principal component analysis and selection index were consistent with the UPGMA analysis, and lines 1, 2, 13, 17, 26, and 31 were classified as PUE. PMID:27173309

  5. Farmland Runoff of Nitrogen and Phosphorus in Songhuajiang Watershed

    Science.gov (United States)

    Yuan, Ruixia; Wang, Zhaohui; Song, Xinshan; Liu, Jianshe; Dong, Jianwei

    2010-05-01

    Qianguo Irrigation District is typical soda saline-alkaline land of Songhuajiang Watershed, where the excess irrigation for leaching Na+ from the root zone has aggravated the non-point source pollution (NPS) from agricultural system and therefore threatened the water quality of Chagan Lake, a national nature reserve. A field experiment with independent irrigation system was conducted to elucidate the dynamic characteristics of nitrogen (N) and phosphorus (P) in surface water of paddy field under different hydrotechnic conditions and their potential environmental impact in 2009. The results showed that split N fertilizer application with four times and single basal application of P fertilizer greatly increased the concentration of nitrate nitrogen (NO3--N), total nitrogen (TN), soluble phosphorus (SP) and total phosphorus in surface water, and then subsequently declined. During all the experimental period, the concentration of N and P in paddy field runoff in the investigated area were TN 1.08~3.90 mg/L, TP 1.32~3.87 mg/L respectively, higher than the surface water quality criteria of Class III and Class V in China, therefore N and P losses from paddy soils during each drainage were contributing to downstream water eutrophication. N and P in runoff mainly consist of particulate phosphorus (PP) and NO3--N, respectively. During rainfall or paddy growth period, the concentration of N and P in the runoff tended to temporal decrease, but showed great fluctuation during irrigation and heavy rainfall. Pollution load of the experimental plot showed that either N and P loss amount or the variation coefficient of TN and TP concentration in drainage was significantly positively correlated with the hydrotechnic conditions. N and P runoff from paddy field directly affected the eutrophication level of offtakes and hence deteriorated the downstream aquatic environment. The ammonia concentration of the return water from farmland was rather high, thus threatening the fish farming in

  6. Alternative Agriculture

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Will the popularization of bioenergy, a new source for powering China, trigger another agricultural revolution? Skyrocketing energy prices, especially the oil shock in the first half of 2005, are pushing China to seek more substitutes for gasoline. A number of cities are turning to ethanol-blended gas made from com. Starting this month, the sale of regular gasoline will be brought to an end in nine of China's

  7. Black phosphorus nonvolatile transistor memory

    Science.gov (United States)

    Lee, Dain; Choi, Yongsuk; Hwang, Euyheon; Kang, Moon Sung; Lee, Seungwoo; Cho, Jeong Ho

    2016-04-01

    We demonstrated nanofloating gate transistor memory devices (NFGTMs) using mechanically-exfoliated few-layered black phosphorus (BP) channels and gold nanoparticle (AuNPs) charge trapping layers. The resulting BP-NFGTMs exhibited excellent memory performances, including the five-level data storage, large memory window (58.2 V), stable retention (104 s), and cyclic endurance (1000 cycles).We demonstrated nanofloating gate transistor memory devices (NFGTMs) using mechanically-exfoliated few-layered black phosphorus (BP) channels and gold nanoparticle (AuNPs) charge trapping layers. The resulting BP-NFGTMs exhibited excellent memory performances, including the five-level data storage, large memory window (58.2 V), stable retention (104 s), and cyclic endurance (1000 cycles). Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02078j

  8. Phosphorus doping a semiconductor particle

    Science.gov (United States)

    Stevens, G.D.; Reynolds, J.S.

    1999-07-20

    A method of phosphorus doping a semiconductor particle using ammonium phosphate is disclosed. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried with the phosphorus then being diffused into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement. 1 fig.

  9. Agricultural problems

    International Nuclear Information System (INIS)

    Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned

  10. IMPROVING PHOSPHORUS NUTRITION OF COTTON

    OpenAIRE

    Walter B. Gordon; Larry Murphy; Pawel Wiatrak

    2014-01-01

    Crop recovery of applied Phosphorus (P) fertilizer can be low, especially during season of low soil temperature, which decreases plant root growth and nutrient uptake. The H2PO4- or HPO4-2 anions readily react with soil cations such as Calcium (Ca), Magnesium (Mg), iron (Fe) and Aluminum (Al) to produce various phosphate compounds of very limited water solubility. Specialty Ferti...

  11. Abiotic and prebiotic phosphorus chemistry

    OpenAIRE

    Micheletti, Gabriele

    2011-01-01

    The chief obstacle to understand the metabolic origin of life or RNA-based life is to identify a plausible mechanism for overcoming the clutter wrought by abiotic chemistry. Probably trough simple abiotic and then prebiotic reactions we could arrive to simple pre-RNA molecules. Here we report a possible preibiotic synthesis for heterocyclic compounds, and a self-assembling process of adenosine phosphates a constituent of RNA. In these processes we use a simple and prebiotic phosphorus cyc...

  12. The Galactic evolution of phosphorus

    CERN Document Server

    Caffau, E; Faraggiana, R; Steffen, M

    2011-01-01

    As a galaxy evolves, its chemical composition changes and the abundance ratios of different elements are powerful probes of the underlying evolutionary processes. Phosphorous is an element whose evolution has remained quite elusive until now, because it is difficult to detect in cool stars. The infrared weak P I lines of the multiplet 1, at 1050-1082 nm, are the most reliable indicators of the presence of phosphorus. The availability of CRIRES at VLT has permitted access to this wavelength range in stellar spectra.We attempt to measure the phosphorus abundance of twenty cool stars in the Galactic disk. The spectra are analysed with one-dimensional model-atmospheres computed in Local Thermodynamic Equilibrium (LTE). The line formation computations are performed assuming LTE. The ratio of phosphorus to iron behaves similarly to sulphur, increasing towards lower metallicity stars. Its ratio with respect to sulphur is roughly constant and slightly larger than solar, [P/S]=0.10+- 0.10. We succeed in taking an impo...

  13. Phytoextraction of excess soil phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Nilesh C. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Starnes, Daniel L. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Sahi, Shivendra V. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States)]. E-mail: shiv.sahi@wku.edu

    2007-03-15

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils.

  14. Evaluation of total phosphorus mass balance in the lower Boise River and selected tributaries, southwestern Idaho

    Science.gov (United States)

    Etheridge, Alexandra B.

    2013-01-01

    he U.S. Geological Survey (USGS), in cooperation with Idaho Department of Environmental Quality, developed spreadsheet mass-balance models for total phosphorus using results from three synoptic sampling periods conducted in the lower Boise River watershed during August and October 2012, and March 2013. The modeling reach spanned 46.4 river miles (RM) along the Boise River from Veteran’s Memorial Parkway in Boise, Idaho (RM 50.2), to Parma, Idaho (RM 3.8). The USGS collected water-quality samples and measured streamflow at 14 main-stem Boise River sites, two Boise River north channel sites, two sites on the Snake River upstream and downstream of its confluence with the Boise River, and 17 tributary and return-flow sites. Additional samples were collected from treated effluent at six wastewater treatment plants and two fish hatcheries. The Idaho Department of Water Resources quantified diversion flows in the modeling reach. Total phosphorus mass-balance models were useful tools for evaluating sources of phosphorus in the Boise River during each sampling period. The timing of synoptic sampling allowed the USGS to evaluate phosphorus inputs to and outputs from the Boise River during irrigation season, shortly after irrigation ended, and soon before irrigation resumed. Results from the synoptic sampling periods showed important differences in surface-water and groundwater distribution and phosphorus loading. In late August 2012, substantial streamflow gains to the Boise River occurred from Middleton (RM 31.4) downstream to Parma (RM 3.8). Mass-balance model results indicated that point and nonpoint sources (including groundwater) contributed phosphorus loads to the Boise River during irrigation season. Groundwater exchange within the Boise River in October 2012 and March 2013 was not as considerable as that measured in August 2012. However, groundwater discharge to agricultural tributaries and drains during non-irrigation season was a large source of discharge and

  15. Potential Phosphorus Mobilisation in Peat Soils

    DEFF Research Database (Denmark)

    Forsmann, Ditte M.; Kjærgaard, Charlotte

    2012-01-01

    Re-establishment of wetlands on peat soils containing phosphorus bound to iron(III)-oxides can lead to an undesirable phosphorus loss to the aquatic environment due to the reductive dissolution of iron(III)-oxides. Thus it is important to be able to assess the potential phosphorus mobilisation from...... peat soils before a re-establishment takes place. The potential phosphorus mobilisation from a peat soil depends not only on the geochemical characteristics but also on the redox conditions, the hydrological regime in the area as well as the hydro-physical properties of the soil. The hypothesis...... for this study is (i) the release of phosphorus in peat is controlled by the geochemistry; (ii) the mobilisation of phosphorus is controlled by both geochemistry and hydro-physics of the soil. For this study, 10 Danish riparian lowland areas with peat soil were selected based on their geochemical characteristics...

  16. The Story of Phosphorus : Sustainability implications of global phosphorus scarcity for food security

    OpenAIRE

    Cordell, Dana

    2010-01-01

    The story of phosphorus began with the search for the philosopher’s stone, and centuries later the critical role of phosphorus in soil fertility and crop growth was highlighted. Eventually, phosphorus was implicated in the global environmental challenge of eutrophication. Now, we are on the brink of yet another emerging chapter in the story: global phosphorus scarcity linked to food security. Through a transdisciplinary and systemic inquiry, this thesis has analyzed, reconceptualized and synt...

  17. Performance assessment of food safety management systems in animal-based food companies in view of their context characteristics: A European study

    NARCIS (Netherlands)

    Luning, P.A.; Kirezieva, K.; Hagelaar, G.; Rovira, J.; Uyttendaele, M.; Jacxsens, L.

    2015-01-01

    Recurrently the question arises if efforts in food safety management system (FSMS) have resulted in effective systems in animal-based food production systems. The aim of this study was to gain an insight in the performance of FSMS in European animal-based food production companies in view of their t

  18. Exploring the Impact of Prior Knowledge and Appropriate Feedback on Students' Perceived Cognitive Load and Learning Outcomes: Animation-Based Earthquakes Instruction

    Science.gov (United States)

    Yeh, Ting-Kuang; Tseng, Kuan-Yun; Cho, Chung-Wen; Barufaldi, James P.; Lin, Mei-Shin; Chang, Chun-Yen

    2012-01-01

    The aim of this study was to develop an animation-based curriculum and to evaluate the effectiveness of animation-based instruction; the report involved the assessment of prior knowledge and the appropriate feedback approach, for the purpose of reducing perceived cognitive load and improving learning. The curriculum was comprised of five subunits…

  19. Effects of WOE Presentation Types Used in Pre-Training on the Cognitive Load and Comprehension of Content in Animation-Based Learning Environments

    Science.gov (United States)

    Jung, Jung,; Kim, Dongsik; Na, Chungsoo

    2016-01-01

    This study investigated the effectiveness of various types of worked-out examples used in pre-training to optimize the cognitive load and enhance learners' comprehension of the content in an animation-based learning environment. An animation-based learning environment was developed specifically for this study. The participants were divided into…

  20. Agricultural ponds support amphibian populations

    Science.gov (United States)

    Knutson, M.G.; Richardson, W.B.; Reineke, D.M.; Gray, B.R.; Parmelee, J.R.; Weick, S.E.

    2004-01-01

    In some agricultural regions, natural wetlands are scarce, and constructed agricultural ponds may represent important alternative breeding habitats for amphibians. Properly managed, these agricultural ponds may effectively increase the total amount of breeding habitat and help to sustain populations. We studied small, constructed agricultural ponds in southeastern Minnesota to assess their value as amphibian breeding sites. Our study examined habitat factors associated with amphibian reproduction at two spatial scales: the pond and the landscape surrounding the pond. We found that small agricultural ponds in southeastern Minnesota provided breeding habitat for at least 10 species of amphibians. Species richness and multispecies reproductive success were more closely associated with characteristics of the pond (water quality, vegetation, and predators) compared with characteristics of the surrounding landscape, but individual species were associated with both pond and landscape variables. Ponds surrounded by row crops had similar species richness and reproductive success compared with natural wetlands and ponds surrounded by nongrazed pasture. Ponds used for watering livestock had elevated concentrations of phosphorus, higher turbidity, and a trend toward reduced amphibian reproductive success. Species richness was highest in small ponds, ponds with lower total nitrogen concentrations, tiger salamanders (Ambystoma tigrinum) present, and lacking fish. Multispecies reproductive success was best in ponds with lower total nitrogen concentrations, less emergent vegetation, and lacking fish. Habitat factors associated with higher reproductive success varied among individual species. We conclude that small, constructed farm ponds, properly managed, may help sustain amphibian populations in landscapes where natural wetland habitat is rare. We recommend management actions such as limiting livestock access to the pond to improve water quality, reducing nitrogen input, and

  1. Phosphorus removal in aerated stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ghigliazza, R.; Lodi, A.; Rovatti, M. [Inst. of Chemical and Process Engineering ``G.B. Bonino``, Univ. of Genoa (Italy)

    1999-03-01

    The possibility to obtain biological phosphorus removal in strictly aerobic conditions has been investigated. Experiments, carried out in a continuous stirred tank reactor (CSTR), show the feasibility to obtain phosphorus removal without the anaerobic phase. Reactor performance in terms of phosphorus abatement kept always higher then 65% depending on adopted sludge retention time (SRT). In fact increasing SRT from 5 days to 8 days phosphorus removal and reactor performance increase but overcoming this SRT value a decreasing in reactor efficiency was recorded. (orig.) With 6 figs., 3 tabs., 18 refs.

  2. Influence of feeding various phosphorus sources on apparent digestibility of phosphorus in dairy cows

    NARCIS (Netherlands)

    Ekelund, A.; Sporndly, R.; Valk, H.; Murphy, M.

    2003-01-01

    The present investigated differences in the apparent digestibility of phosphorus (ADP) in lactating cows fed various feed materials containing organic forms of phosphorus (P) or a highly available inorganic phosphorus source. Cows milking an average of 36 kg energy corrected milk (ECM) were used in

  3. Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options

    NARCIS (Netherlands)

    Cordell, D.; Rosemarin, A.; Schroder, J.J.; Smit, A.L.

    2011-01-01

    Human intervention in the global phosphorus cycle has mobilised nearly half a billion tonnes of the element from phosphate rock into the hydrosphere over the past half century. The resultant water pollution concerns have been the main driver for sustainable phosphorus use (including phosphorus recov

  4. Evaluation of phosphorus source coefficients as predictors of runoff phosphorus concentrations.

    Science.gov (United States)

    Smith, Matt C; White, John W; Coale, Frank J

    2009-01-01

    Many states have adopted a P site index (PSI) as a risk assessment tool to determine when P-based nutrient management is required for a given agricultural field. Some PSIs use a weighting factor, the phosphorus source coefficient (PSC), to account for differences in P solubility between organic P sources. Information relating to appropriate values of PSC for various organic P sources is limited. The objectives of this study were to determine PSCs for organic P sources and to examine the relationship between PSCs and P concentrations measured in simulated rainfall runoff. An incubation study was used to calculate PSCs based on the extractability of P from organic P sources (separated and unseparated liquid dairy manure, digested dairy manure, dairy manure solids, poultry litter, and compost) relative to P from triple superphosphate fertilizer. The PSCs from the 14-d incubations were the best predictors of runoff P after 14 d soil equilibration in the runoff boxes. The values for iron-oxide strip phosphorus (FeO-P) PSC ranged from 78% for compost to 28% for poultry litter and were significantly related to runoff DR-P (r(2) = 0.80***) and FeO-P (r(2) = 0.76***) during the 14-d runoff event. Mehlich 3 PSCs ranged from 59% for compost to 30% for unseparated dairy manure and were better predictors of DR-P and FeO-P during the 56-d event (r(2) = 0.73*** and 0.65***, respectively). The results of this study indicate that PSCs based on soil incubations may improve the ability of PSCs to predict the risk of runoff transport, particularly after manure incorporation. PMID:19202029

  5. Probing Phosphorus Efficient Low Phytic Acid Content Soybean Genotypes with Phosphorus Starvation in Hydroponics Growth System.

    Science.gov (United States)

    Kumar, Varun; Singh, Tiratha Raj; Hada, Alkesh; Jolly, Monica; Ganapathi, Andy; Sachdev, Archana

    2015-10-01

    Phosphorus is an essential nutrient required for soybean growth but is bound in phytic acid which causes negative effects on both the environment as well as the animal nutrition. Lowering of phytic acid levels is associated with reduced agronomic characteristics, and relatively little information is available on the response of soybean plants to phosphorus (P) starvation. In this study, we evaluated the effects of different P starvation concentrations on the phytic acid content, growth, and yield of seven mutant genotypes along with the unirradiated control, JS-335, in a hydroponics growth system. The low phytic acid containing mutant genotypes, IR-JS-101, IR-DS-118, and IR-V-101, showed a relatively high growth rate in low P concentration containing nutrient solution (2 μM), whereas the high P concentration (50 μM) favored the growth of IR-DS-111 and IR-DS-115 mutant genotypes containing moderate phytate levels. The mutant genotypes with high phytic acid content, IR-DS-122, IR-DS-114, and JS-335, responded well under P starvation and did not have any significant effect on the growth and yield of plants. Moreover, the reduction of P concentration in nutrient solution from 50 to 2 μM also reduced the phytic acid content in the seeds of all the soybean genotypes under study. The desirable agronomic performance of low phytic acid containing mutant genotype IR-DS-118 reported in this study suggested it to be a P-efficient genotype which could be considered for agricultural practices under P limiting soils. PMID:26239443

  6. Probing Phosphorus Efficient Low Phytic Acid Content Soybean Genotypes with Phosphorus Starvation in Hydroponics Growth System.

    Science.gov (United States)

    Kumar, Varun; Singh, Tiratha Raj; Hada, Alkesh; Jolly, Monica; Ganapathi, Andy; Sachdev, Archana

    2015-10-01

    Phosphorus is an essential nutrient required for soybean growth but is bound in phytic acid which causes negative effects on both the environment as well as the animal nutrition. Lowering of phytic acid levels is associated with reduced agronomic characteristics, and relatively little information is available on the response of soybean plants to phosphorus (P) starvation. In this study, we evaluated the effects of different P starvation concentrations on the phytic acid content, growth, and yield of seven mutant genotypes along with the unirradiated control, JS-335, in a hydroponics growth system. The low phytic acid containing mutant genotypes, IR-JS-101, IR-DS-118, and IR-V-101, showed a relatively high growth rate in low P concentration containing nutrient solution (2 μM), whereas the high P concentration (50 μM) favored the growth of IR-DS-111 and IR-DS-115 mutant genotypes containing moderate phytate levels. The mutant genotypes with high phytic acid content, IR-DS-122, IR-DS-114, and JS-335, responded well under P starvation and did not have any significant effect on the growth and yield of plants. Moreover, the reduction of P concentration in nutrient solution from 50 to 2 μM also reduced the phytic acid content in the seeds of all the soybean genotypes under study. The desirable agronomic performance of low phytic acid containing mutant genotype IR-DS-118 reported in this study suggested it to be a P-efficient genotype which could be considered for agricultural practices under P limiting soils.

  7. Changes in soil carbon, nitrogen, and phosphorus due to land-use changes in Brazil

    Science.gov (United States)

    Groppo, J. D.; Lins, S. R. M.; Camargo, P. B.; Assad, E. D.; Pinto, H. S.; Martins, S. C.; Salgado, P. R.; Evangelista, B.; Vasconcellos, E.; Sano, E. E.; Pavão, E.; Luna, R.; Martinelli, L. A.

    2015-08-01

    In this paper, soil carbon, nitrogen and phosphorus concentrations and stocks were investigated in agricultural and natural areas in 17 plot-level paired sites and in a regional survey encompassing more than 100 pasture soils In the paired sites, elemental soil concentrations and stocks were determined in native vegetation (forests and savannas), pastures and crop-livestock systems (CPSs). Nutrient stocks were calculated for the soil depth intervals 0-10, 0-30, and 0-60 cm for the paired sites and 0-10, and 0-30 cm for the pasture regional survey by sum stocks obtained in each sampling intervals (0-5, 5-10, 10-20, 20-30, 30-40, 40-60 cm). Overall, there were significant differences in soil element concentrations and ratios between different land uses, especially in the surface soil layers. Carbon and nitrogen contents were lower, while phosphorus contents were higher in the pasture and CPS soils than in native vegetation soils. Additionally, soil stoichiometry has changed with changes in land use. The soil C : N ratio was lower in the native vegetation than in the pasture and CPS soils, and the carbon and nitrogen to available phosphorus ratio (PME) decreased from the native vegetation to the pasture to the CPS soils. In the plot-level paired sites, the soil nitrogen stocks were lower in all depth intervals in pasture and in the CPS soils when compared with the native vegetation soils. On the other hand, the soil phosphorus stocks were higher in all depth intervals in agricultural soils when compared with the native vegetation soils. For the regional pasture survey, soil nitrogen and phosphorus stocks were lower in all soil intervals in pasture soils than in native vegetation soils. The nitrogen loss with cultivation observed here is in line with other studies and it seems to be a combination of decreasing organic matter inputs, in cases where crops replaced native forests, with an increase in soil organic matter decomposition that leads to a decrease in the long

  8. Phosphorus availability from rock phosphate: Combined effect of green waste composting and sulfur addition.

    Science.gov (United States)

    Bustamante, M A; Ceglie, F G; Aly, A; Mihreteab, H T; Ciaccia, C; Tittarelli, F

    2016-11-01

    Rock phosphate constitutes a natural phosphorus (P) source for organic farming systems, but with a limiting direct agricultural use due to its poor inherent reactivity. Thus, this work studies the effect of the co-composting of rock phosphate with green wastes and elemental sulfur on phosphorus availability. Six composts were prepared combining different green wastes and rock phosphate in three different proportions (0%, 0.27% and 0.54% P fresh mass basis) and elemental sulfur in two proportions (0% and 0.5% S fresh mass basis). During composting, the temperature of the mixtures was monitored, as were physico-chemical and chemical parameters, especially those related to phosphorus. The co-composting of green wastes with rock phosphate improved phosphorus mobilization and also constituted a viable method to manage green wastes, obtaining P-enriched compost for organic farming systems. Sulfur addition favored the composting process and also phosphorus solubilization, especially in the mixture with the lowest proportion of rock phosphate. PMID:27543750

  9. Phosphorus diffusion in polycrystalline silicon

    Science.gov (United States)

    Losee, D. L.; Lavine, J. P.; Trabka, E. A.; Lee, S.-T.; Jarman, C. M.

    1984-02-01

    The diffusion of phosphorus in crystallized amorphous Si layers was studied with secondary-ion mass spectroscopy. A two-dimensional diffusion model is used to find effective grain (Dg) and grain-boundary (Dgb) diffusion coefficients. This simplified model leads to Dgb ≤ 10Dg, which is significantly lower than what has been deduced from conventional, larger grained polysilicon. Our result is consistent with specific-gravity measurements, which found a significantly lower ``mass defect'' for layers deposited amorphous and subsequently crystallized as compared to initially polycrystalline layers.

  10. WHO WOULD EAT IN A WORLD WITHOUT PHOSPHORUS? A GLOBAL DYNAMIC MODEL

    Science.gov (United States)

    Dumas, M.

    2009-12-01

    Phosphorus is an indispensable and non-substitutable resource, as agriculture is impossible if soils do not hold adequate amounts of this nutrient. Phosphorus is also considered to be a non-renewable and increasingly scarce resource, as phosphate rock reserves - as one measure of availability amongst others - are estimated to last for 50 to 100 years at current rates of consumption. How would food production decline in different parts of the world in the scenario of a sudden shortage in phosphorus? To answer this question and explore management scenarios, I present a probabilistic model of the structure and dynamics of the global P cycle in the world’s agro-ecosystems. The model proposes an original solution to the challenge of capturing the large-scale aggregate dynamics of multiple micro-scale soil cycling processes. Furthermore, it integrates the essential natural processes with a model of human-managed flows, thereby bringing together several decades of research and measurements from soil science, plant nutrition and long-term agricultural experiments from around the globe. In this paper, I present the model, the first simulation results and the implications for long-term sustainable management of phosphorus and soil fertility.

  11. Sedimentary phosphorus cycling and a phosphorus mass balance for the Green Bay (Lake Michigan) ecosystem

    Science.gov (United States)

    Klump, J.V.; Edgington, D. N.; Sager, P.E.; Robertson, D.M.

    2011-01-01

    The tributaries of Green Bay have long been recognized as major sources of phosphorus in the Lake Michigan basin. The status of Green Bay as a sink or source of phosphorus for Lake Michigan proper has been less well defined. The bay receives nearly 70% of its annual load of phosphorus ( 700 metric tons (t) · year-1) from a single source: the Fox River. Most of this phosphorus is deposited in sediments accumulating at rates that reach 160 mg · cm-2 · year-1 with an average of 20 mg · cm-2 · year-1. The phosphorus content of these sediments varies from 70 µmol · g-1. Deposition is highly focused, with ~70% of the total sediment accumulation and at least 80% of the phosphorus burial occurring within 20% of the surface area of the bay. Diagenetic and stoichiometric models of phosphorus cycling imply that >80% of the phosphorus deposited is permanently buried. External phosphorus loading to the bay is combined with sediment fluxes of phophorus to arrive at a simple phosphorus budget. Green Bay acts as an efficient nutrient trap, with the sediments retaining an estimated 70-90% of the external phosphorus inputs before flowing into Lake Michigan.

  12. Global Hindcasts and Future Projections of Coastal Nitrogen and Phosphorus Loads Due to Shellfish and Seaweed Aquaculture

    NARCIS (Netherlands)

    Bouwman, A.F.; Pawlowski, M.; Liu, C.; Beusen, A.W.H.; Shumway, S.E.; Glibert, P.M.; Overbeek, C.C.

    2011-01-01

    A model was developed to estimate nitrogen and phosphorus budgets for aquaculture production of crustaceans, bivalves, gastropods, and seaweed, using country production data for the 1970–2006 period from the Food and Agriculture Organi- zation and scenarios based on the Millenium Assessment for 2006

  13. X-ray fluorescence spectrometry-based approach to precision management of bioavailable phosphorus in soil environments

    Science.gov (United States)

    Declining nutrient use efficiency in crop production has been a global priority to preserve high agricultural productivity with finite non-renewable nutrient resources, in particular phosphorus (P). Rapid spectroscopic methods increase measurement density of soil nutrients, and the availability of ...

  14. Modelling long-term phophorus leaching and changes in phosphorus fertility in excessively fertilized acid sandy soils

    NARCIS (Netherlands)

    del Campillo, M.C.; Zee, van der S.E.A.T.M.; Torrent, J.

    1999-01-01

    The sound management of agricultural soils that are heavily loaded with phosphorus (P) involves minimizing the losses of P responsible for eutrophication of surface waters, while ensuring enough P for crops. This paper describes a simple model to examine the compatibility of these two objectives in

  15. Predicting the potential of soils to supply phosphorus by integrating soil chemical processes and standard soil tests

    NARCIS (Netherlands)

    Los, A.M.D.; Bussink, D.W.; Temminghoff, E.J.M.; Riemsdijk, van W.H.

    2012-01-01

    In agriculture there is a growing need to use phosphorus (P) fertilizer more efficiently because of P related environmental problems and diminishing P reserves. A key factor to achieve this is an accurate prediction of the P supply potential of a soil. To improve the choice of soil tests and interpr

  16. Energy and phosphorus recovery from black water

    NARCIS (Netherlands)

    Graaff, de M.S.; Temmink, B.G.; Zeeman, G.; Buisman, C.J.N.

    2011-01-01

    Source-separated black water (BW) (toilet water) containing 38% of the organic material and 68% of the phosphorus in the total household waste (water) stream including kitchen waste, is a potential source for energy and phosphorus recovery. The energy recovered, in the form of electricity and heat,

  17. Solutions Network Formulation Report. The Potential Contributions of the Global Precipitation Measurement Mission to Phosphorus Reduction Efforts in the Florida Everglades

    Science.gov (United States)

    Anderson, Daniel; Hilbert, Kent; Lewis, David

    2009-01-01

    This candidate solution suggests the use of GPM precipitation observations to enhance the CERP. Specifically, GPM measurements could augment in situ precipitation data that are used to model agricultural phosphorus discharged into the Everglades. This solution benefits society by aiding water resource managers in identifying effective phosphorus reduction scenarios and thereby returning the Everglades to a more natural state. This solution supports the Water Management, Coastal Management, and Ecological Forecasting National Applications.

  18. Risk assessment of chemicals in food and diet: Hazard identification by methods of animal-based toxicology

    DEFF Research Database (Denmark)

    Barlow, S. M.; Greig, J. B.; Bridges, J. W.;

    2002-01-01

    the current state of the science of risk assessment of chemicals in food and diet, by consideration of the four stages of risk assessment, that is. hazard identification. hazard characterisation, exposure assessment and risk characterisation. The contribution of animal-based methods in toxicology to hazard......, on hazard identification for food chemicals, such as new measurement techniques, the use of transgenic animals, assessment of hormone balance and the possibilities for conducting studies in which common human diseases have been modelled. is also considered. (C) 2002 ILSI. Published by Elsevier Science Ltd....... All rights reserved....

  19. Agriculture ideas and modernization of agriculture

    OpenAIRE

    Li Kangmin

    2011-01-01

    The development of agriculture has its own history from primitive agriculture, traditional agriculture to modem agriculture. Is it a historical road we must follow?Human being had experienced a long history of living on collection and hunting for about 2,000 to 3,000 millenniums since human being appeared on earth. After we settled down, another 10 millenniums passed. Human being began to cultivate crops and raise animals. Thus, we entered the primitive agriculture stage. The primitive agricu...

  20. Global availability of phosphorus and its implications for global food supply: An economic overview

    OpenAIRE

    Heckenmüller, Markus; Narita, Daiju; Klepper, Gernot

    2014-01-01

    Being of crucial importance for agricultural production and also having experienced significant price volatility, phosphate and its future availability have drawn growing at-tention from both academics and the public over the last years. This paper overviews the recent literature and data on the availability of phosphorus and discusses the eco-nomic aspects of phosphate scarcity by describing major price determinants of the global phosphate market. We show that past price fluctuations of phos...

  1. Phosphorus speciation of clay fractions from long-term fertility experiments in Sweden

    OpenAIRE

    Eriksson, Ann Kristin; Gustafsson, Jon Petter; Hesterberg, Dean

    2015-01-01

    Phosphorus (P) losses from agricultural soils constitute a main driver for eutrophication of the Baltic Sea. There is limited knowledge about sorption and release processes of P in these soils, especially concerning the effects of fertilization. In this study, P speciation of the clay fractions from six different soils in long-term fertility experiments in Sweden was investigated by P K-edge XANES spectroscopy. As expected, unfertilized soils had lower concentrations of acid-digestible P comp...

  2. Early maize root and phosphorus uptake responses to localised application of sewage sludge derived fertilisers

    OpenAIRE

    Lemming, Camilla; Oberson, Astrid; Hund, Andreas; Stoumann Jensen, Lars; Magid, Jakob

    2015-01-01

    Background: Phosphorus recycling from waste and localised placement of fertilisers can be means to improve sustainable P management in agriculture. However, knowledge about root and plant P uptake responses to placement of complex waste- derived fertilisers is lacking. Methods: Sewage sludge (SS) and sewage sludge ash (ASH) were tested against triple superphosphate (TSP) in a rhizobox setup where shoot and root growth of maize was followed for 30 days. The three P sources were either mixed...

  3. Assessment of Alternative Phosphorus Fertilizers for Organic Farming: Meat and Bone Meal

    OpenAIRE

    Möller, Kurt (Prof. Dr. phil. habil.)

    2015-01-01

    In the past meat and bone meal was a major source of nutrients for recycling back to agricultural land, either as animal feed or organic nitrogen and phosphorus fertilizer. Nowadays - since the Bovine Spongiform Encephalopathy (BSE) crisis in 1999 - it is mainly used as fertilizer. Although meat and bone meals are allowed by EU regulation in organic farming, several growers’ organisations prohibited them since the BSE crisis. Incineration or melting in a cupola furnace are alternative treatme...

  4. Bronx River bed sediments phosphorus pool and phosphorus compound identification

    Science.gov (United States)

    Wang, J.; Pant, H. K.

    2008-12-01

    Phosphorus (P) transport in the Bronx River degraded water quality, decreased oxygen levels, and resulted in bioaccumulation in sediment potentially resulting in eutrophication, algal blooms and oxygen depletion under certain temperature and pH conditions. The anthropogenic P sources are storm water runoff, raw sewage discharge, fertilizer application in lawn, golf course and New York Botanical Garden; manure from the Bronx zoo; combined sewoverflows (CSO's) from parkway and Hunts Point sewage plant; pollutants from East River. This research was conducted in the urban river system in New York City area, in order to control P source, figure out P transport temporal and spatial variations and the impact on water quality; aimed to regulate P application, sharing data with Bronx River Alliance, EPA, DEP and DEC. The sediment characteristics influence the distribution and bioavailbility of P in the Bronx River. The P sequential extraction gave the quantitative analysis of the P pool, quantifying the inorganic and organic P from the sediments. There were different P pool patterns at the 15 sites, and the substantial amount of inorganic P pool indicated that a large amount P is bioavailable. The 31P- NMR (Nuclear Magnetic Resonance Spectroscopy) technology had been used to identify P species in the 15 sites of the Bronx River, which gave a qualitative analysis on phosphorus transport in the river. The P compounds in the Bronx River bed sediments are mostly glycerophophate (GlyP), nucleoside monophosphates (NMP), polynucleotides (PolyN), and few sites showed the small amount of glucose-6-phosphate (G6P), glycerophosphoethanoamine (GPEA), phosphoenopyruvates (PEP), and inosine monophosphate (IMP). The land use spatial and temporal variations influence local water P levels, P distributions, and P compositions.

  5. Impact of phosphorus control measures on in-river phosphorus retention associated with point source pollution

    Science.gov (United States)

    Demars, B. O. L.; Harper, D. M.; Pitt, J.-A.; Slaughter, R.

    2005-06-01

    In-river phosphorus retention alters the quantity and timings of phosphorus delivery to downstream aquatic systems. Many intensive studies of in-river phosphorus retention have been carried out but generally on a short time scale (2-4 years). In this paper, monthly water quality data, collected by the Environment Agency of England and Wales over 12 years (1990-2001), were used to model daily phosphorus fluxes and monthly in-river phosphorus retention in the lowland calcareous River Wensum, Norfolk, UK. The calibrated model explained 79% and 89% of the observed variance before and after phosphorus control, respectively. A split test revealed that predicted TP loads were in good agreement with observed TP loads (r2=0.85), although TP loads were underestimated under high flow conditions. During relatively dry years, there was no net export of phosphorus from the catchment. High retention of phosphorus occurred, particularly during the summer months, which was not compensated for, by subsequent higher flow events. This was despite a relatively modest critical discharge (Q) above which net remobilisation occur. Phosphorus removal from the effluent at two major STWs (Sewage Treatment Works) reduced phosphorus retention but not the remobilisation. This may indicate that the presence of impoundments and weirs, or overbank flows may have more control on the phosphorus dynamics under high flow conditions. Further phosphorus remedial strategies will be necessary to prevent downstream risks of eutrophication occurring independently of the unpredictable variability in weather conditions. More research is also needed to quantify the impact of the weir and overbank flows on phosphorus dynamics.

  6. Impact of phosphorus control measures on in-river phosphorus retention associated with point source pollution

    Directory of Open Access Journals (Sweden)

    B. O. L. Demars

    2005-01-01

    Full Text Available In-river phosphorus retention alters the quantity and timings of phosphorus delivery to downstream aquatic systems. Many intensive studies of in-river phosphorus retention have been carried out but generally on a short time scale (2-4 years. In this paper, monthly water quality data, collected by the Environment Agency of England and Wales over 12 years (1990-2001, were used to model daily phosphorus fluxes and monthly in-river phosphorus retention in the lowland calcareous River Wensum, Norfolk, UK. The calibrated model explained 79% and 89% of the observed variance before and after phosphorus control, respectively. A split test revealed that predicted TP loads were in good agreement with observed TP loads (r2=0.85, although TP loads were underestimated under high flow conditions. During relatively dry years, there was no net export of phosphorus from the catchment. High retention of phosphorus occurred, particularly during the summer months, which was not compensated for, by subsequent higher flow events. This was despite a relatively modest critical discharge (Q above which net remobilisation occur. Phosphorus removal from the effluent at two major STWs (Sewage Treatment Works reduced phosphorus retention but not the remobilisation. This may indicate that the presence of impoundments and weirs, or overbank flows may have more control on the phosphorus dynamics under high flow conditions. Further phosphorus remedial strategies will be necessary to prevent downstream risks of eutrophication occurring independently of the unpredictable variability in weather conditions. More research is also needed to quantify the impact of the weir and overbank flows on phosphorus dynamics.

  7. Agriculture ideas and modernization of agriculture

    Directory of Open Access Journals (Sweden)

    Li Kangmin

    2011-12-01

    Full Text Available The development of agriculture has its own history from primitive agriculture, traditional agriculture to modem agriculture. Is it a historical road we must follow?Human being had experienced a long history of living on collection and hunting for about 2,000 to 3,000 millenniums since human being appeared on earth. After we settled down, another 10 millenniums passed. Human being began to cultivate crops and raise animals. Thus, we entered the primitive agriculture stage. The primitive agriculture lasted for 7,000 years to get our food security on primitive crop cultivation and animal raising.

  8. WelFur-mink: on-farm welfare assessment of mink (Neovision vision) - effect of sample size on animal based measures

    DEFF Research Database (Denmark)

    Rousing, Tine; Møller, Steen Henrik; Hansen, Steffen W

    2012-01-01

    " in validity, reliability as well as feasibility - the latter both as regards time and economy costs. This paper based on empiric data addressed the questions on needed sample size for a robust herd assessment of animal based measures. The animal based part of the full WelFur protocol including 9 animal based......European Fur Breeder's Association initiated the "WelFur project" in 2009 which is aiming at developing an applicable on farm welfare assessment protocol for mink based on the Welfare Quality® principles. Such a welfare assessment system should possess the following qualities: It should be "high...... in herd prevalence of the mentioned parameters. Statistical analyses showed that a sample size of 125 adult mink was a robus estimate of the herd level of animal based measures....

  9. [Spatial and Temporal Distribution Characteristics of Different Forms of Phosphorus in Three Sorts of Rivers around Lake Taihu].

    Science.gov (United States)

    Gao, Yong-xia; Song, Yu-zhi; Yu, Jiang-hua; Zhu, Guang-wei

    2016-04-15

    Different forms of phosphorus from the upper reaches of river to lower reaches of river in nine rivers were analyzed to clarify the pollution characteristics of industrial effluent, agriculture effluent and sanitary wastewater to Lake Taihu in February (low water period), May (average water period) and August (abundant water period) of 2009. The results showed that total phosphorus (TP) dissolved total phosphorus (DTP) and soluble reactive phosphorus ( SRP) mass concentration all showed decreasing trend while enzymatic phosphorus (EHP) mass concentration increased with the increase of algal biomass from low water period to abundant water period. Mass concentrations of several forms of phosphorus were all the highest in the rivers impacted by sanitary wastewater, but sanitary wastewater's self-purification capabity from the upper reaches of river to lower reaches of river was the best, and the pollution to Lake Taihu was the lowest. Pollution from rivers impacted by industrial effluent was the highest. Mass concentration of EHP was higher than that of SRP in most cases, so EHP played an important role in Cyanbacterial harmful algal blooms events in Lake Taihu. PMID:27548962

  10. IMPROVING PHOSPHORUS NUTRITION OF CORN

    Directory of Open Access Journals (Sweden)

    Walter B. Gordon

    2014-01-01

    Full Text Available Phosphorus (P generally occurs in soils as the anions H2PO4- or HPO4-2 depending on soil pH. These anions readily react with soil cations such as calcium, magnesium, iron and aluminum to produce various phosphate compounds of very limited water solubility. Crop recovery of applied phosphate fertilizer can be quite low during the season of application. In addition, the large amounts of crop residue present in no-tillage production systems can lower soil temperature thus reducing root growth and nutrient uptake of plants even on soils not low in available Phosphorus (P. Specialty Fertilizer Products, Leawood, KS has developed and patented a product registered as AVAIL® that is reported to attract and sequester antagonistic cations out of the soil solution leaving more of the applied P in available form for plant uptake. The objective of this experiment was to evaluate the effectiveness of AVAIL treated P-fertilizer on growth, P-uptake and yield of irrigated corn (Zea mays L. grown in a no-tillage production system. A 3-year experiment was conducted from 2001-2003 at the North Central Kansas Experiment Field, located near Scandia, KS, on a Crete silt loam soil (fine, montmorillonitic, mesic Pachic Arquistoll. Treatments consisted of three rates of P with or without AVAIL. A no P check plot was also included. When averaged over the years and P rates, the use of AVAIL increased yield of corn by 1.1 Mg ha-1. AVAIL also increased corn dry weight at the six-leaf stage, whole plant P uptake at the six-leaf stage and P concentration at mid-silk. The use of AVAIL proved beneficial in overcoming many of the problems associated with P nutrition in corn. AVAIL consistently increased P uptake and yield in this experiment.

  11. Molecular Mechanisms of Phosphorus Metabolism and Transport during Leaf Senescence

    Directory of Open Access Journals (Sweden)

    Kyla A. Stigter

    2015-12-01

    Full Text Available Leaf senescence, being the final developmental stage of the leaf, signifies the transition from a mature, photosynthetically active organ to the attenuation of said function and eventual death of the leaf. During senescence, essential nutrients sequestered in the leaf, such as phosphorus (P, are mobilized and transported to sink tissues, particularly expanding leaves and developing seeds. Phosphorus recycling is crucial, as it helps to ensure that previously acquired P is not lost to the environment, particularly under the naturally occurring condition where most unfertilized soils contain low levels of soluble orthophosphate (Pi, the only form of P that roots can directly assimilate from the soil. Piecing together the molecular mechanisms that underpin the highly variable efficiencies of P remobilization from senescing leaves by different plant species may be critical for devising effective strategies for improving overall crop P-use efficiency. Maximizing Pi remobilization from senescing leaves using selective breeding and/or biotechnological strategies will help to generate P-efficient crops that would minimize the use of unsustainable and polluting Pi-containing fertilizers in agriculture. This review focuses on the molecular mechanisms whereby P is remobilized from senescing leaves and transported to sink tissues, which encompasses the action of hormones, transcription factors, Pi-scavenging enzymes, and Pi transporters.

  12. Validation of a quantitative phosphorus loss assessment tool.

    Science.gov (United States)

    White, Michael J; Storm, Daniel E; Smolen, Michael D; Busteed, Philip R; Zhang, Hailin; Fox, Garey A

    2014-01-01

    Pasture Phosphorus Management Plus (PPM Plus) is a tool that allows nutrient management and conservation planners to evaluate phosphorus (P) loss from agricultural fields. This tool uses a modified version of the widely used Soil and Water Assessment Tool model with a vastly simplified interface. The development of PPM Plus has been fully described in previous publications; in this article we evaluate the accuracy of PPM Plus using 286 field-years of runoff, sediment, and P validation data from runoff studies at various locations in Oklahoma, Texas, Arkansas, and Georgia. Land uses include pasture, small grains, and row crops with rainfall ranging from 630 to 1390 mm yr, with and without animal manure application. PPM Plus explained 68% of the variability in total P loss, 56% of runoff, and 73% of the variability of sediment yield. An empirical model developed from these data using soil test P, total applied P, slope, and precipitation only accounted for 15% of the variability in total P loss, which implies that a process-based model is required to account for the diversity present in these data. PPM Plus is an easy-to-use conservation planning tool for P loss prediction, which, with modification, could be applicable at the regional and national scales. PMID:25602555

  13. The fate of phosphorus fertilizer in Amazon soya bean fields.

    Science.gov (United States)

    Riskin, Shelby H; Porder, Stephen; Neill, Christopher; Figueira, Adelaine Michela e Silva; Tubbesing, Carmen; Mahowald, Natalie

    2013-06-01

    Fertilizer-intensive soya bean agriculture has recently expanded in southeastern Amazonia, and whereas intensive fertilizer use in the temperate zone has led to widespread eutrophication of freshwater ecosystems, the effects in tropical systems are less well understood. We examined the fate of fertilizer phosphorus (P) by comparing P forms and budgets across a chronosequence of soya bean fields (converted to soya beans between 2003 and 2008) and forests on an 800 km(2) soya bean farm in Mato Grosso, Brazil. Soya bean fields were fertilized with 50 kg P ha(-1) yr(-1) (30 kg P ha(-1) yr(-1) above what is removed in crops). We used modified Hedley fractionation to quantify soil P pools and found increases in less-plant-available inorganic pools and decreases in organic pools in agricultural soils compared with forest. Fertilizer P did not move below 20 cm. Measurements of P sorption capacity suggest that while fertilizer inputs quench close to half of the sorption capacity of fast-reacting pools, most added P is bound in more slowly reacting pools. Our data suggest that this agricultural system currently has a low risk of P losses to waterways and that long time-scales are required to reach critical soil thresholds that would allow continued high yields with reduced fertilizer inputs.

  14. Impact of phosphorus control measures on in-river phosphorus retention associated with point source pollution

    Directory of Open Access Journals (Sweden)

    B. O. L. Demars

    2005-01-01

    Full Text Available In-river phosphorus retention alters the quantity and timings of phosphorus delivery to downstream aquatic systems. Many intensive studies of in-river phosphorus retention have been carried out but generally on a short time scale (2-4 years. In this paper, monthly water quality data, collected by the Environment Agency of England and Wales over 12 years (1990-2001, were used to model daily phosphorus fluxes and monthly in-river phosphorus retention in the lowland calcareous River Wensum, Norfolk, UK. The effectiveness of phosphorus stripping at two major sewage treatment works was quantified over different hydrological conditions. The model explained 78% and 88% of the observed variance before and after phosphorus control, respectively. During relatively dry years, there was no net export of phosphorus from the catchment. High retention of phosphorus occurred, particularly during the summer months, which was not compensated for, by subsequent higher flow events. The critical discharge (Q above which net remobilisation would occur, was only reached during few, high flow events Q25-Q13. Phosphorus removal from the effluent at two major STWs (Sewage Treatment Works reduced the phosphorus catchment mass balance variability by 20-24% under the Q99-Q1. range of flow conditions. Although the absorbing capacity of the catchment against human impact was remarkable, further phosphorus remedial strategies will be necessary to prevent downstream risks of eutrophication occuring independently of the unpredictable variability in weather conditions.

  15. Epitaxial Growth of Single Layer Blue Phosphorus: A New Phase of Two-Dimensional Phosphorus.

    Science.gov (United States)

    Zhang, Jia Lin; Zhao, Songtao; Han, Cheng; Wang, Zhunzhun; Zhong, Shu; Sun, Shuo; Guo, Rui; Zhou, Xiong; Gu, Cheng Ding; Yuan, Kai Di; Li, Zhenyu; Chen, Wei

    2016-08-10

    Blue phosphorus, a previously unknown phase of phosphorus, has been recently predicted by theoretical calculations and shares its layered structure and high stability with black phosphorus, a rapidly rising two-dimensional material. Here, we report a molecular beam epitaxial growth of single layer blue phosphorus on Au(111) by using black phosphorus as precursor, through the combination of in situ low temperature scanning tunneling microscopy and density functional theory calculation. The structure of the as-grown single layer blue phosphorus on Au(111) is explained with a (4 × 4) blue phosphorus unit cell coinciding with a (5 × 5) Au(111) unit cell, and this is verified by the theoretical calculations. The electronic bandgap of single layer blue phosphorus on Au(111) is determined to be 1.10 eV by scanning tunneling spectroscopy measurement. The realization of epitaxial growth of large-scale and high quality atomic-layered blue phosphorus can enable the rapid development of novel electronic and optoelectronic devices based on this emerging two-dimensional material. PMID:27359041

  16. Urban Agriculture Guide

    NARCIS (Netherlands)

    Visser, A.J.; Jansma, J.E.; Dekking, A.J.G.; Klieverik, M.J.M.

    2007-01-01

    The Urban Agriculture Guide describes the experiences, learning moments, tips and tricks of those involved in the initiatives of urban agriculture and an indication is provided of what is required to develop urban agriculture further in the Netherlands

  17. Agricultural Tariff Tracker

    Data.gov (United States)

    Foreign Agricultural Service, Department of Agriculture — The Agricultural Tariff Tool is a web application that queries tariff schedules and rate information resulting from Free Trade Agreements (FTAs). All...

  18. Agricultural Education at Risk.

    Science.gov (United States)

    Evans, Donald E.

    1988-01-01

    Discusses educational reform in the context of agricultural education. Covers a recent report on agricultural education reform by the National Academy of Sciences, state legislative initiatives, and several recommendations for the future of agricultural education. (CH)

  19. Agricultural recycling of biodigested vinasse for lettuce production

    Directory of Open Access Journals (Sweden)

    Camila Roberta Javorski Ueno

    2014-10-01

    Full Text Available The agricultural use of waste products represents an interesting alternative for nutrient cycling. Biodigested vinasse, the final waste product of vinasse biodigestion and biogas production, can be reused for agricultural purposes. The present work sought to quantify the shoot dry mass production of lettuce plants, as well as foliar nitrogen, phosphorus and potassium content following the application of biodigested vinasse on soil. Biodigested vinasse was produced from anaerobic vinasse digestion, using anaerobic sludge as a source of microorganisms. The treatments, with four replications in entirely randomized design, consisted of anaerobic sludge from a gelatin factory, vinasse in natura, biodigested vinasse and a control treatment. The experiment was conducted over 45 days using 5 L vases and applying a dose equivalent to 150 m3 ha-1 . Lettuce treated with biodigested vinasse showed higher shoot dry mass production and higher accumulation of nitrogen, phosphorus and potassium in its leaves than that treated with vinasse in natura.

  20. Total Phosphorus in Surface Water (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Excess phosphorus in surface water can result in eutrophication. TOTALPFuture is reported in kilograms/hectare/year. More information about these resources,...

  1. [Lack of phosphorus intake and nutrition].

    Science.gov (United States)

    Takeda, Eiji; Ikeda, Syoko; Nakahashi, Otoki

    2012-10-01

    Since one gram of protein in food provides approximately 15 mg of phosphorus, phosphorus deficiency frequently observed in patients with protein-energy malnutrition (PEM). Chronic phosphorus deficiency in humans causes proximal myopathy. Acute hypophosphatemia may precipitate rhabdomyolysis. Plasma low phosphorus concentration suppresses erythrocyte synthesis and stores of 2,3-diphosphoglycerate (2,3-DPG) , which plays an important role in the affinity of hemoglobin for oxygen. Symptoms of nervous system dysfunction, such as weakness, apathy, a bedridden state, and intention tremors, are also observed in severe hypophosphatemia. Refeeding syndrome is caused by rapid refeeding in PEM, characterized by hypophosphatemia and has metabolic and clinical complications. This is potentially fatal, yet is preventable. Awareness and identification of at-risk patients is crucial to improving management.

  2. Effect of Phosphorus and Irrigation Levels on Yield, Water Productivity, Phosphorus Use Efficiency and Income of Lowland Rice in Northwest Pakistan

    Institute of Scientific and Technical Information of China (English)

    Khalid USMAN

    2013-01-01

    With decreasing availability of water for agriculture and increasing demand for rice production,an optimum use of irrigation water and phosphorus may guarantee sustainable rice production.Field experiments were conducted in 2003 and 2004 to investigate the effect of phosphorus and irrigation levels on yield,water productivity (WP),phosphorus use efficiency (PUE) and income of low land rice.The experiment was laid out in randomized complete block design with split plot arrangements replicated four times.Main plot consisted of five phosphorus levels,viz.0 (P0),50 (P50),100 (P100),150(P150),and 200 (P200) kg/hm2,while subplots contained of irrigation times,i.e.8 (I8),10 (I10),12 (I12),and 14 (I14) irrigation levels,each with a water depth of 7.5 cm.Mean values revealed that P150 in combination with I10 produced the highest paddy yield (9.8 t/hm2) and net benefit (1231.8 US$/hm2)among all the treatments.Phosphorus enhanced WP when applied in appropriate combination with irrigation level.The highest mean WP [13.3 kg/(hm2·mm)] could be achieved at P150 with I8 and decreased with increase in irrigation level,while the highest mean PUE (20.1 kg/kg) could be achieved at P100 with I10 and diminished with higher P levels.The overall results indicate that P150 along with I10 was the best combination for sustainable rice cultivation in silty clay soil.

  3. Atmospheric deposition of phosphorus to land and freshwater.

    Science.gov (United States)

    Tipping, E; Benham, S; Boyle, J F; Crow, P; Davies, J; Fischer, U; Guyatt, H; Helliwell, R; Jackson-Blake, L; Lawlor, A J; Monteith, D T; Rowe, E C; Toberman, H

    2014-07-01

    We compiled published and newly-obtained data on the directly-measured atmospheric deposition of total phosphorus (TP), filtered total phosphorus (FTP), and inorganic phosphorus (PO4-P) to open land, lakes, and marine coasts. The resulting global data base includes data for c. 250 sites, covering the period 1954 to 2012. Most (82%) of the measurement locations are in Europe and North America, with 44 in Africa, Asia, Oceania, and South-Central America. The deposition rates are log-normally distributed, and for the whole data set the geometric mean deposition rates are 0.027, 0.019 and 0.14 g m(-2) a(-1) for TP, FTP and PO4-P respectively. At smaller scales there is little systematic spatial variation, except for high deposition rates at some sites in Germany, likely due to local agricultural sources. In cases for which PO4-P was determined as well as one of the other forms of P, strong parallels between logarithmic values were found. Based on the directly-measured deposition rates to land, and published estimates of P deposition to the oceans, we estimate a total annual transfer of P to and from the atmosphere of 3.7 Tg. However, much of the phosphorus in larger particles (principally primary biological aerosol particles) is probably redeposited near to its origin, so that long-range transport, important for tropical forests, large areas of peatland and the oceans, mainly involves fine dust from deserts and soils, as described by the simulations of Mahowald et al. (Global Biogeochemical Cycles 22, GB4026, 2008). We suggest that local release to the atmosphere and subsequent deposition bring about a pseudo-diffusive redistribution of P in the landscape, with P-poor ecosystems, for example ombrotrophic peatlands and oligotrophic lakes, gaining at the expense of P-rich ones. Simple calculations suggest that atmospheric transport could bring about significant local redistribution of P among terrestrial ecosystems. Although most atmospherically transported P is natural

  4. Possibility in optimization of biological phosphorus removal

    Energy Technology Data Exchange (ETDEWEB)

    Schoenberger, R.

    1989-02-01

    The elimination-efficiency of wastewater treatment plants with biological phosphorus removal is often limited by the following aspects: Low concentrations of organic acids in influent wastewater, hydraulic- and load fluctuations, low anaerobic sludge detention time, transfer of nitrate into the anaerobic zone, phosphorus release in the final clarifier and in sludge treatment units, high effluent suspended solids content. In this context, the following optimization measures seem to be advantageous: 'Activated primary tanks' and 'activated sludge thickeners' are adequate techniques to raise the concentration of organic acids in the wastewater by pre-acidification. Simultaneous acidification takes place in an anaerobic sedimentation basin as realized in the EASC-process (extended anaerobic sludge contact). Below the sludge blanket of an EASC-sedimentation tank, anaerobic conditions can be maintained even in the case of nitrate input. Furthermore, this process is suitable to compensate load- and hydraulic fluctuations of wastewater. To avoid phosphorus release in the final clarifier, it is important to improve sludge settleability. If a low sludge blanket and/or high oxygen concentrations are maintained, phosphorus release in the final clarifier can be limited. Further reduction of total phosphorus is possible with filtration only. Measures against high return flow phosphorus loads are mechanical dewatering of excess sludge and chemical precipitation of digester supernatant.

  5. Recovery of phosphorus from sewerage treatment sludge

    Energy Technology Data Exchange (ETDEWEB)

    Manuilova, Anastasia

    1999-07-01

    This thesis is a review of the current state of technologies for the removal of phosphorus from wastewater and sludge, and the recovery and re-use of phosphorus. It explains the need for phosphorus removal and describes the current removal processes. Focus is given to phosphorus crystallisation processes and to the processes which treat sewage treatment sludges into potential sources of phosphorus. An interesting possibility to recover phosphorus from sewage sludge by use of Psenner fractionation is also discussed. By this method, the following phosphate fractions of technological significance may be distinguished: (1) redox sensitive phosphates, mainly bound to Fe(OH){sub 3}; (2) phosphate adsorbed to surfaces (Al{sub 2}O{sub 3}), exchangeable against OH{sup -}, and alkali-soluble phosphate; (3) phosphate bound to CaCO{sub 3}, MgCO{sub 3} and in apatite; and (4) organically bound phosphate. The basic removal mechanisms, process schemes and treatment results are described. Two experiments with three different types of sludges from Henriksdal wastewater treatment plant in Stockholm were performed in the laboratory. It was shown that the addition of sodium hydroxide or hydrochloric acid cause the significant release of phosphate (about 80%) for all types of sludges. If a whole Psenner fractionation was performed the phosphate release is approximately 100%.

  6. Soil phosphorus constrains biodiversity across European grasslands.

    Science.gov (United States)

    Ceulemans, Tobias; Stevens, Carly J; Duchateau, Luc; Jacquemyn, Hans; Gowing, David J G; Merckx, Roel; Wallace, Hilary; van Rooijen, Nils; Goethem, Thomas; Bobbink, Roland; Dorland, Edu; Gaudnik, Cassandre; Alard, Didier; Corcket, Emmanuel; Muller, Serge; Dise, Nancy B; Dupré, Cecilia; Diekmann, Martin; Honnay, Olivier

    2014-12-01

    Nutrient pollution presents a serious threat to biodiversity conservation. In terrestrial ecosystems, the deleterious effects of nitrogen pollution are increasingly understood and several mitigating environmental policies have been developed. Compared to nitrogen, the effects of increased phosphorus have received far less attention, although some studies have indicated that phosphorus pollution may be detrimental for biodiversity as well. On the basis of a dataset covering 501 grassland plots throughout Europe, we demonstrate that, independent of the level of atmospheric nitrogen deposition and soil acidity, plant species richness was consistently negatively related to soil phosphorus. We also identified thresholds in soil phosphorus above which biodiversity appears to remain at a constant low level. Our results indicate that nutrient management policies biased toward reducing nitrogen pollution will fail to preserve biodiversity. As soil phosphorus is known to be extremely persistent and we found no evidence for a critical threshold below which no environmental harm is expected, we suggest that agro-environmental schemes should include grasslands that are permanently free from phosphorus fertilization.

  7. Phosphorus speciation by coupled HPLC-ICPMS: low level determination of reduced phosphorus in natural materials

    Science.gov (United States)

    Atlas, Zachary; Pasek, Matthew; Sampson, Jacqueline

    2015-04-01

    Phosphorus is a geologically important minor element in the Earth's crust commonly found as relatively insoluble apatite. This constraint causes phosphorus to be a key limiting nutrient in biologic processes. Despite this, phosphorus plays a direct role in the formation of DNA, RNA and other cellular materials. Recent works suggest that since reduced phosphorus is considerably more soluble than oxidized phosphorus that it was integrally involved in the development of life on the early Earth and may continue to play a role in biologic productivity to this day. This work examines a new method for quantification and identification of reduced phosphorus as well as applications to the speciation of organo-phosphates separated by coupled HPLC - ICP-MS. We show that reduced phosphorus species (P1+, P3+ and P5+) are cleanly separated in the HPLC and coupled with the ICPMS reaction cell, using oxygen as a reaction gas to effectively convert elemental P to P-O. Analysis at M/Z= 47 producing lower background and flatter baseline chromatography than analyses performed at M/Z = 31. Results suggest very low detection limits (0.05 μM) for P species analyzed as P-O. Additionally we show that this technique has potential to speciate at least 5 other forms of phosphorus compounds. We verified the efficacy of method on numerous materials including leached Archean rocks, suburban retention pond waters, blood and urine samples and most samples show small but detectible levels of reduced phosphorus and or organo-phaospates. This finding in nearly all substances analyzed supports the assumption that the redox processing of phosphorus has played a significant role throughout the history of the Earth and it's presence in the present environment is nearly ubiquitous with the reduced oxidation state phosphorus compounds, phosphite and hypophosphite, potentially acting as significant constituents in the anaerobic environment.

  8. CeO2-covered nanofiber for highly efficient removal of phosphorus from aqueous solution.

    Science.gov (United States)

    Ko, Young Gun; Do, Taegu; Chun, Youngsang; Kim, Choong Hyun; Choi, Ung Su; Kim, Jae-Yong

    2016-04-15

    The lowering phosphorus concentration of lakes or rivers using adsorbents has been considered to be the most effective way to prevent water eutrophication. However, the development of an adsorbent is still challenging because conventional adsorbents have not shown a sufficient phosphorus adsorption capacity (0.3-2.0mmol/g) to treat industrial, agricultural or domestic wastewater at a large scale. Herein, a novel and effective strategy to remove phosphorus efficiently with a CeO2-covered nanofiber is shown. The CeO2-covered nanofiber was synthesized through (1) amine group immobilization onto an electrospun polyacrylonitrile nanofiber and (2) adsorption of Ce(3+) on it. The CeO2-covered nanofiber played a role in catching phosphate ions in an aqueous solution by the oxidation, reduction, and ion-exchange of adsorbed Ce(3+) on the nanofiber from CeO2 to CePO4, and enabled remarkable phosphate adsorption capacity of the nanofiber (ca. 17.0mmol/g) at the range of ca. pH 2-6. Our strategy might be the most feasible method to efficiently lower the phosphorus concentration in lakes or rivers owing to the easy and inexpensive preparation of CeO2-covered nanofiber at an industrial scale, with a high phosphate adsorption capacity. PMID:26795705

  9. Phosphorus recovery from wastewater--expert survey on present use and future potential.

    Science.gov (United States)

    Sartorius, Christan; von Horn, Jana; Tettenborn, Felix

    2012-04-01

    Today, a variety of different approaches to the recovery of phosphorus from wastewater, sludge, and sludge ash exist. These approaches differ basically by the origin of the used matter (wastewater, sludge liquor, fermented or nonfermented sludge ash) and the process (precipitation, wet-chemical extraction, and thermal treatment). To rate them according to their characteristics, the latter were phrased as hypotheses and subjected to an international expert survey. The survey showed that phosphorus recovery is expected to become an established process over the next 20 years in industrialized countries for economic reasons. A decisive aspect in this regard will be the quality of the produced fertilizer. Simple technologies such as the recovery from sludge liquor seem to be preferred. If sludge is incinerated, phosphorus recycling from ash then becomes more interesting and has to be considered. Phosphorus recovery and source-separating sanitation technologies are more appropriate for industrialized countries than for developing countries. Because the growing awareness of environmental issues will prevent sludge from being used agriculturally in an increasing number of countries in the next decade, the market potential for nutrient recovery technologies will increase in the immediate future. PMID:22834219

  10. Potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment.

    Science.gov (United States)

    Havukainen, Jouni; Nguyen, Mai Thanh; Hermann, Ludwig; Horttanainen, Mika; Mikkilä, Mirja; Deviatkin, Ivan; Linnanen, Lassi

    2016-03-01

    All life forms require phosphorus (P), which has no substitute in food production. The risk of phosphorus loss from soil and limited P rock reserves has led to the development of recycling P from industrial residues. This study investigates the potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment (ASH DEC) in Finland. An ASH DEC plant could receive 46-76 kt/a of sewage sludge ash to produce 51-85 kt/a of a P-rich product with a P2O5 content of 13-18%, while 320-750 kt/a of manure ash could be supplied to produce 350-830 kt/a of a P-rich product with a P content of 4-5%. The P2O5 potential in the total P-rich product from the ASH DEC process using sewage sludge and manure ash is estimated to be 25-47 kt/a, which is significantly more than the P fertilizer demand in Finland's agricultural industries. The energy efficiency of integrated incineration and the ASH DEC process is more dependent on the total solid content and the subsequent need for mechanical dewatering and thermal drying than on the energy required by the ASH DEC process. According to the results of this study, the treated sewage sludge and manure ash using the ASH DEC process represent significant potential phosphorus sources for P fertilizer production. PMID:26810030

  11. The renaissance of black phosphorus

    Science.gov (United States)

    Ling, Xi; Wang, Han; Huang, Shengxi; Xia, Fengnian; Dresselhaus, Mildred S.

    2015-04-01

    One hundred years after its first successful synthesis in the bulk form in 1914, black phosphorus (black P) was recently rediscovered from the perspective of a 2D layered material, attracting tremendous interest from condensed matter physicists, chemists, semiconductor device engineers, and material scientists. Similar to graphite and transition metal dichalcogenides (TMDs), black P has a layered structure but with a unique puckered single-layer geometry. Because the direct electronic band gap of thin film black P can be varied from 0.3 eV to around 2 eV, depending on its film thickness, and because of its high carrier mobility and anisotropic in-plane properties, black P is promising for novel applications in nanoelectronics and nanophotonics different from graphene and TMDs. Black P as a nanomaterial has already attracted much attention from researchers within the past year. Here, we offer our opinions on this emerging material with the goal of motivating and inspiring fellow researchers in the 2D materials community and the broad readership of PNAS to discuss and contribute to this exciting new field. We also give our perspectives on future 2D and thin film black P research directions, aiming to assist researchers coming from a variety of disciplines who are desirous of working in this exciting research field.

  12. Total Value of Phosphorus Recovery.

    Science.gov (United States)

    Mayer, Brooke K; Baker, Lawrence A; Boyer, Treavor H; Drechsel, Pay; Gifford, Mac; Hanjra, Munir A; Parameswaran, Prathap; Stoltzfus, Jared; Westerhoff, Paul; Rittmann, Bruce E

    2016-07-01

    Phosphorus (P) is a critical, geographically concentrated, nonrenewable resource necessary to support global food production. In excess (e.g., due to runoff or wastewater discharges), P is also a primary cause of eutrophication. To reconcile the simultaneous shortage and overabundance of P, lost P flows must be recovered and reused, alongside improvements in P-use efficiency. While this motivation is increasingly being recognized, little P recovery is practiced today, as recovered P generally cannot compete with the relatively low cost of mined P. Therefore, P is often captured to prevent its release into the environment without beneficial recovery and reuse. However, additional incentives for P recovery emerge when accounting for the total value of P recovery. This article provides a comprehensive overview of the range of benefits of recovering P from waste streams, i.e., the total value of recovering P. This approach accounts for P products, as well as other assets that are associated with P and can be recovered in parallel, such as energy, nitrogen, metals and minerals, and water. Additionally, P recovery provides valuable services to society and the environment by protecting and improving environmental quality, enhancing efficiency of waste treatment facilities, and improving food security and social equity. The needs to make P recovery a reality are also discussed, including business models, bottlenecks, and policy and education strategies. PMID:27214029

  13. Soil phosphorus availability and soybean response to phosphorus starter fertilizer

    Directory of Open Access Journals (Sweden)

    Ciro Antonio Rosolem

    2014-10-01

    Full Text Available Phosphorus fixation in tropical soils may decrease under no-till. In this case, P fertilizer could be surface-spread, which would improve farm operations by decreasing the time spend in reloading the planter with fertilizers. In the long term, less soluble P sources could be viable. In this experiment, the effect of surface-broadcast P fertilization with both soluble and reactive phosphates on soil P forms and availability to soybean was studied with or without fertilization with soluble P in the planting furrow in a long-term experiment in which soybean was grown in rotation with Ruzigrass (Brachiaria ruziziensis. No P or 80 kg ha-1 of P2O5 in the form of triple superphosphate or Arad reactive rock phosphate was applied on the surface of a soil with variable P fertilization history. Soil samples were taken to a depth of 60 cm and soil P was fractionated. Soybean was grown with 0, 30, and 60 kg ha-1 of P2O5 in the form of triple phosphate applied in the seed furrow. Both fertilizers applied increased available P in the uppermost soil layers and the moderately labile organic and inorganic forms of P in the soil profile, probably as result of root decay. Soybean responded to phosphates applied on the soil surface or in the seed furrow; however, application of soluble P in the seed furrow should not be discarded. In tropical soils with a history of P fertilization, soluble P sources may be substituted for natural reactive phosphates broadcast on the surface. The planting operation may be facilitated through reduction in the rate of P applied in the planting furrow in relation to the rates currently applied.

  14. Journal of Integrative Agriculture

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Aims and Scope Journal of Integrative Agriculture (JIA), formerly Agricultural Sciences in China (ASC), founded in 2002, is an official publication of the Chinese Academy of Agricultural Sciences (CAAS). JIA seeks to publish those papers that are influential and will significantly advance scientific understanding in agriculture fields worldwide.

  15. Sustainable agriculture - selected papers

    OpenAIRE

    Krasowicz, Stanisław; Wrzaszcz, Wioletta; Zegar, Jozef St.

    2007-01-01

    The concept of research on socially sustainable agriculture. Features of sustainable agriculture. Sustainability of private farms in the light of selected criteria. Subsistence agricultural holdings and the sustainable development of agriculture. Sustainable farms in the light of the FADN data. Description of organic holdings in Poland.

  16. Using SWAT to Target Critical Source Sediment and Phosphorus Areas in the Wister Lake Basin, USA

    Directory of Open Access Journals (Sweden)

    Philip R. Busteed

    2009-01-01

    Full Text Available Problem statement: Wister Lake is located in the San Bois Mountains in southeastern Oklahoma, USA. The reservoir is primarily used as a water supply and flood storage to over 40,000 residents in the area. Due to high levels of phosphorus and sediment, Wister Lake is listed as a high priority basin for the State of Oklahoma. To help address these water quality problems, the Oklahoma Conservation Commission provided cost share funds for landowners in the basin to implement conservation practices. Approach: The objective of this study was to identify or target agricultural land that contributed disproportional pollutant losses, i.e. critical source areas. Results: Implementing conservation practice in these critical source areas allowed optimal placement conservation practices. The Soil and Water Assessment Tool (SWAT model was used to identify critical source areas of phosphorus and sediment in the Wister Lake basin. SWAT predicted 57,000 metric tons a year of sediment and 84,000 kilograms a year of total phosphorus from upland areas in the basin. Eighty-five percent of the pollutant load originated from just 10% of the basin. Conclusion/Recommendations: This allowed the OCC to identify and contact specific agricultural producers to recruit into their water quality program, which optimized the use of limited cost share funds.

  17. Integrating Phosphorus Movement with Soil and Water Loss in the Daily Erosion Project

    Science.gov (United States)

    Sklenar, Tim; Perez-Bidegain, Mario; Cruse, Richard; Gelder, Brian; Herzmann, Daryl

    2016-04-01

    The Daily Erosion Project (DEP) is an ongoing modelling effort which is now in its second generation. DEP provides comprehensive and dynamic estimates of sediment delivery, soil erosion, and hill slope runoff for agricultural land areas across the Midwestern United States every day for Hydrologic Unit Code 12 (HUC 12) size watersheds. Results are posted every morning on the Internet at dailyerosion.org. Currently DEP covers all of Iowa and portions of Kansas and Minnesota, but expansion of coverage is ongoing. The integration of highly resolute spatial and temporal climate data, soil properties, crop rotation and residue management data affords the opportunity to test the effects of using multiple conservation practices on the transport and fate of water borne nutrients, especially phosphorus, on the Midwestern United States agricultural landscapes. Understanding the interaction of different environmental and land management practices on phosphorus movement will allow data from the DEP to guide conservation efforts as expansion continues into surrounding Midwestern states. The presentation will provide an overview of the DEP technology, including how input data are derived and used to make daily erosion estimates on over 200,000 flowpaths in the modelling area, as well as a discussion of the ongoing phosphorus transport modelling efforts and plans for future expansion (both land area and model functionality).

  18. Greenhouse evaluation and environmental impact assessment of different urine-derived struvite fertilizers as phosphorus sources for plants.

    Science.gov (United States)

    Antonini, Samantha; Arias, Maria Alejandra; Eichert, Thomas; Clemens, Joachim

    2012-11-01

    A selection of six urine-derived struvite fertilizers generated by innovative precipitation technologies was assessed for their quality and their effectiveness as phosphorus sources for crops. Struvite purity was influenced by drying techniques and magnesium dosage. In a greenhouse experiment, the urine fertilizers led to biomass yields and phosphorus uptakes comparable to or higher than those induced by a commercial mineral fertilizer. Heavy metal concentrations of the different struvite fertilizers were below the threshold limits specified by the German Fertilizer and Sewage Sludge Regulations. The computed loading rates of heavy metals to agricultural land were also below the threshold limits decreed by the Federal Soil Protection Act. Urine-derived struvite contributed less to heavy metal inputs to farmland than other recycling products or commercial mineral and organic fertilizers. When combined with other soil conditioners, urine-derived struvite is an efficient fertilizer which covers the magnesium and more than half of the phosphorus demand of crops.

  19. Kinetic analysis of anaerobic phosphorus release during biological phosphorus removal process

    Institute of Scientific and Technical Information of China (English)

    DOU Junfeng; LUO Guyuan; LIU Xiang

    2007-01-01

    Enhanced biological phosphorus removal(EBPR)is a commonly used and sustainable method for phosphorus removal from wastewater.Poly-β-hydroxybutyrate(PHB),polyphosphate,and glycogen are three kinds of intracellular storage polymers in phosphorus accumulation organisms.The variation of these polymers under different conditions has an apparent influence on anaerobic phosphorus release,which is very important for controlling the performance of EBPR.To obtain the mechanism and kinetic character of anaerobic phosphorus release,a series of batch experiments were performed using the excessively aerated sludge from the aerobic unit of the biological phosphorus removal system in this study.The results showed that the volatile suspended solid(vss)had an increasing trend,while the mixed liquid suspended sludge(MLSS)and ashes were reduced during the anaerobic phosphorus release process.The interruption of anaerobic HAc-uptake and phosphorus-release occurs when the glycogen in the phosphorus-accumulating-organisms is exhausted.Under the condition of lower initial HAc-COD,HAc became the limiting factor after some time for anaerobic HAc uptake.Under the condition of higher initial HAc-COD,HAc uptake was stopped because of the depletion of glycogen in the microorganisms.The mean ratio of △ρP/△ρPHB,△ρGLY/△ρPHB,△ρP/△COD,and △ρPHB/△COD was 0.48,0.50,0.44.and 0.92.respectively,which was nearly the same as the theoretical value.The calibrated kinetic parameters of the HAc-uptake and phosphorus-release model were evaluated as Kgly was 0.005,and KCOD was 3 mg/L.An apparently linear correlation was observed between the ratio of △ρP/△COD and pH of the solution,and the equation between them was obtained in this study.

  20. Critical phosphorus concentrations in winter wheat genotypes with various phosphorus efficiencies

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Under greenhouse conditions, a pot experiment was conducted to seek critical phosphorus concentrations of wheat genotypes with high and low phosphorus use efficiency. Results indicated that low efficient genotype was much more sensitive to phosphorus deficiency, with low or without phosphorus application, seed yield and dry matter of biomass were much lower. The yield of all the genotypes gradually got higher as application rate increased, but high efficient genotype--Lofflin produced relatively higher yields of seeds and biomass with low or without phosphorus input. Highly tolerate to low availability of soil phosphorus and efficient activation and absorption for soil unavailable phosphorus had been displayed. As application rates increased, yields of both genotypes were increased but high efficient genotype maintained stable while low efficient one showed continuously increase with remuneration decrease progressively. Critical phosphorus concentrations in high efficient genotypes of winter wheat were lower than that in low efficient ones and changed with various development stages, for example, at seedling state, the concentrations of high efficient genotype were 4.50-4.60 g/kg while low efficient one was 5.0 g/kg. They were 2.25-2.30 g/kg and 2.52 g/kg at flower stage, 1.96-2.05 g/kg and 2.15 g/kg at maturity respectively. But the values in seeds were reversal, higher in high efficient genotype(4.05-4.10 g/kg) than that in low efficient(3.90 g/kg). Therefore, phosphorus high efficient genotypes belong to the phosphorus resource saving type.

  1. Rainfall intensity and phosphorus source effects on phosphorus transport in surface runoff from soil trays.

    Science.gov (United States)

    Shigaki, Francirose; Sharpley, Andrew; Prochnow, Luis Ignacio

    2007-02-01

    Phosphorus runoff from agricultural fields amended with mineral fertilizers and manures has been linked to freshwater eutrophication. A rainfall simulation study was conducted to evaluate the effects of different rainfall intensities and P sources differing in water soluble P (WSP) concentration on P transport in runoff from soil trays packed with a Berks loam and grassed with annual ryegrass (Lolium multiflorum Lam.). Triple superphosphate (TSP; 79% WSP), low-grade super single phosphate (LGSSP; 50% WSP), North Carolina rock phosphate (NCRP; 0.5% WSP) and swine manure (SM; 70% WSP), were broadcast (100 kg total P ha-1) and rainfall applied at 25, 50 and 75 mm h-1 1, 7, 21, and 56 days after P source application. The concentration of dissolved reactive (DRP), particulate (PP), and total P (TP) was significantly (Prunoff with a rainfall intensity of 75 than 25 mm h-1 for all P sources. Further, runoff DRP increased as P source WSP increased, with runoff from a 50 mm h-1 rain 1 day after source application having a DRP concentration of 0.25 mg L-1 for NCRP and 28.21 mg L-1 for TSP. In contrast, the proportion of runoff TP as PP was greater with low (39% PP for NCRP) than high WSP sources (4% PP for TSP) averaged for all rainfall intensities. The increased PP transport is attributed to the detachment and transport of undissolved P source particles during runoff. These results show that P source water solubility and rainfall intensity can influence P transport in runoff, which is important in evaluating the long-term risks of P source application on P transport in surface runoff.

  2. Animation-Based Teaching of Semiconductor Devices: Long-Term Improvement in Students’ Achievements in a Two-Year College

    Directory of Open Access Journals (Sweden)

    Aharon Gero

    2015-02-01

    Full Text Available The structure and operating principle of semiconductor devices are a central topic in teaching electronics, both in universities and in two-year colleges. Teachers teaching this subject normally run into substantial difficulties stemming from the fact that a major part of the concepts and processes that are relevant to understanding these devices are abstract. In light of the advantages of multimedia in illustrating dynamic processes, the chapter covering the field effect transistor (FET has recently been taught through animation at a two-year college in Israel. The study presented here has examined, through quantitative tools, whether animation-based teaching of the FET had any effect on students’ achievements in the subject of basic electronic devices. Forty electronics students have participated in the study. Its findings indicate that in the short and long term alike, the achievements of students who studied the transistor through animation were significantly higher than those of their peers who studied it through a traditional method. Additionally, the effect size was very large.

  3. Secondary poisoning of kestrels by white phosphorus

    Science.gov (United States)

    Sparling, D.W.; Federoff, N.E.

    1997-01-01

    Since 1982, extensive waterfowl mortality due to white phosphorus (P4) has been observed at Eagle River Flats, a tidal marsh near Anchorage, Alaska. Ducks and swans that ingest P4 pellets become lethargic and may display severe convulsions. Intoxicated waterfowl attract raptors and gulls that feed on dead or dying birds. To determine if avian predators can be affected by secondary poisoning, we fed American kestrels (Falco sparverius) 10-day-old domestic chickens that had been dosed with white phosphorus. Eight of 15 kestrels fed intact chicks with a pellet of P4 implanted in their crops died within seven days. Three of 15 kestrels fed chicks that had their upper digestive tracts removed to eliminate any pellets of white phosphorus also died. Hematocrit and hemoglobin in kestrels decreased whereas lactate dehydrogenaseL, glucose, and alanine aminotransferase levels in plasma increased with exposure to contaminated chicks. Histological examination of liver and kidneys showed that the incidence and severity of lesions increased when kestrels were fed contaminated chicks. White phosphorus residues were measurable in 87% of the kestrels dying on study and 20% of the survivors. This study shows that raptors can become intoxicated either by ingesting portions of digestive tracts containing white phosphorus pellets or by consuming tissues of P4 contaminated prey.

  4. Nutrient and Bacterial Transport From Agricultural Lands Fertlized With Different Animal Manures

    OpenAIRE

    Mishra, Anurag

    2003-01-01

    The increase of animal agriculture coupled with excess manure production, and the reduced availability of land has led to the over application of animal manure on agricultural fields. The excessive application of manure is responsible for nutrient and bacterial pollution of downstream waterbodies. Manure application based on the crop phosphorus (P) requirements has been recommended as a viable method to reduce nutrient pollution. A plot scale study was conducted to measure the loss of nutrien...

  5. Phosphorus from wastewater to crops: An alternative path involving microalgae.

    Science.gov (United States)

    Solovchenko, Alexei; Verschoor, Antonie M; Jablonowski, Nicolai D; Nedbal, Ladislav

    2016-01-01

    Phosphorus (P) is a non-renewable resource, a major plant nutrient that is essential for modern agriculture. Currently, global food and feed production depends on P extracted from finite phosphate rock reserves mainly confined to a small number of countries. P limitation and its potential socio-economic impact may well exceed the potential effects of fossil fuel scarcity. The efficiency of P usage today barely reaches 20%, with the remaining 80% ending up in wastewater or in surface waters as runoff from fields. When recovered from wastewater, either chemically or biologically, P is often present in a form that does not meet specifications for agricultural use. As an alternative, the potential of microalgae to accumulate large quantities of P can be a way to direct this resource back to crop plants. Algae can acquire and store P through luxury uptake, and the P enriched algal biomass can be used as bio-fertilizer. Technology of large-scale algae cultivation has made tremendous progress in the last decades, stimulated by perspectives of obtaining third generation biofuels without requiring arable land or fresh water. These new cultivation technologies can be used for solar-driven recycling of P and other nutrients from wastewater into algae-based bio-fertilizers. In this paper, we review the specifics of P uptake from nutrient-rich waste streams, paying special attention to luxury uptake by microalgal cells and the potential application of P-enriched algal biomass to fertilize crop soils. PMID:26795876

  6. Efficiency of phosphate fertilization to maize crop in high phosphorus content soil, evaluated by {sup 32}P tracer

    Energy Technology Data Exchange (ETDEWEB)

    Trevizam, Anderson R.; Alvarez Villanueva, Felipe C.; Silva, Maria Ligia de S.; Muraoka, Takashi [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Fertilidade do Solo]. E-mails: trevizam@cena.usp.br; falvarez@cena.usp.br; mlsousi@hotmail.com; muraoka@cena.usp.br

    2007-07-01

    Application of high dosis of phosphorus (P) in agricultural soils is justified by its intense fixation by the soil clays, which reduce availability to crops. The objective of this research was to evaluate the response of maize crops to five rates of triple superphosphate in a soil with high available phosphorus content. Portions of 2 dm{sup 3} of soil (Typic Quartzipisamment) with 75 mg kg{sup -1} of available phosphorus and pH 7.00, collected from the upper 0-20 cm layer, were placed in plastic pots, received solution containing 5.55 MBq (150 {mu}Ci) of {sup 32}P and incubated for 7 days. Then 0, 250, 500, 1000 and 4000 mg P kg{sup -1} as triple superphosphate was added to soil in the respective pots and incubated for 15 days keeping the soil moisture to 60 % of the field capacity. Maize (Zea mays L.) plants, single hybrid P30F80, were grown for 50 days (after germination), collected, oven dried, weighed and ground in a Wiley mill for analysis of total P content and {sup 32}P radioactivity. The maize dry matter increased with triple superphosphate rates. The phosphorus content and accumulation in the maize plants increased with triple superphosphate rate up to 4000 mg kg{sup -1}. The percentage of phosphorus derived from the fertilizer ranged from 79 to 97% and consequently the phosphorus derived from soil decreased with increasing application of triple superphosphate. In spite of soil high P available content, maize plants responded to applied phosphorus rates. (author)

  7. Effect of phosphorus-ion implantation on the corrosion resistance and biocompatibility of titanium.

    Science.gov (United States)

    Krupa, D; Baszkiewicz, J; Kozubowski, J A; Barcz, A; Sobczak, J W; Biliński, A; Lewandowska-Szumieł, M; Rajchel, B

    2002-08-01

    This work presents data on the structure and corrosion resistance of titanium after phosphorus-ion implantation with a dose of 10(17)P/cm2. The ion energy was 25keV. Transmission electron microscopy was used to investigate the microstructure of the implanted layer. The chemical composition of the surface layer was examined by X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The corrosion resistance was examined by electrochemical methods in a simulated body fluid at a temperature of 37 C. Biocompatibility tests in vitro were performed in a culture of human derived bone cells in direct contact with the materials tested. Both, the viability of the cells determined by an XTT assay and activity of the cells evaluated by alkaline phosphatase activity measurements in contact with implanted and non-implanted titanium samples were detected. The morphology of the cells spread on the surface of the materials examined was also observed. The results confirmed the biocompatibility of both phosphorus-ion-implanted and non-implanted titanium under the conditions of the experiment. As shown by transmission electron microscope results, the surface layer formed during phosphorus-ion implantation was amorphous. The results of electrochemical examinations indicate that phosphorus-ion implantation increases the corrosion resistance after short-term as well as long-term exposures.

  8. Response of Sugarcane in a Red Ultisol to Phosphorus Rates, Phosphorus Sources, and Filter Cake.

    Science.gov (United States)

    Caione, Gustavo; Prado, Renato de Mello; Campos, Cid Naudi Silva; Rosatto Moda, Leandro; de Lima Vasconcelos, Ricardo; Pizauro Júnior, João Martins

    2015-01-01

    We evaluated the effect of phosphorus application rates from various sources and in the presence or absence of filter cake on soil phosphorus, plant phosphorus, changes in acid phosphatase activity, and sugarcane productivity grown in Eutrophic Red Ultisol. Three P sources were used (triple superphosphate, Araxa rock phosphate, and Bayovar rock phosphate) and four application rates (0, 90, 180, and 360 kg ha(-1) of P2O5) in the presence or absence of filter cake (7.5 t ha(-1), dry basis). The soil P, the accumulated plant P, the leaf acid phosphatase activity and straw, the stalk productivity, the concentration of soluble solids in the juice (Brix), the juice sucrose content (Pol), and the purity were the parameters evaluated. We found that P applications increased levels of soil, leaf, and juice phosphorus and led to higher phosphorus accumulation and greater stalk and straw productivity. These levels were highest in the presence of filter cake. Acid phosphatase activity decreased with increasing plant phosphorus concentration. Phosphate fertilization did not show effect on sugarcane technological quality. We concluded that P application, regardless of source, improved phosphorus nutrition and increased productivity in sugarcane and, when associated with filter cake, reduced the need for mineral fertilizer. PMID:26078993

  9. Response of Sugarcane in a Red Ultisol to Phosphorus Rates, Phosphorus Sources, and Filter Cake

    Science.gov (United States)

    Prado, Renato de Mello; Campos, Cid Naudi Silva; Rosatto Moda, Leandro; de Lima Vasconcelos, Ricardo; Pizauro Júnior, João Martins

    2015-01-01

    We evaluated the effect of phosphorus application rates from various sources and in the presence or absence of filter cake on soil phosphorus, plant phosphorus, changes in acid phosphatase activity, and sugarcane productivity grown in Eutrophic Red Ultisol. Three P sources were used (triple superphosphate, Araxa rock phosphate, and Bayovar rock phosphate) and four application rates (0, 90, 180, and 360 kg ha−1 of P2O5) in the presence or absence of filter cake (7.5 t ha−1, dry basis). The soil P, the accumulated plant P, the leaf acid phosphatase activity and straw, the stalk productivity, the concentration of soluble solids in the juice (Brix), the juice sucrose content (Pol), and the purity were the parameters evaluated. We found that P applications increased levels of soil, leaf, and juice phosphorus and led to higher phosphorus accumulation and greater stalk and straw productivity. These levels were highest in the presence of filter cake. Acid phosphatase activity decreased with increasing plant phosphorus concentration. Phosphate fertilization did not show effect on sugarcane technological quality. We concluded that P application, regardless of source, improved phosphorus nutrition and increased productivity in sugarcane and, when associated with filter cake, reduced the need for mineral fertilizer. PMID:26078993

  10. Response of Sugarcane in a Red Ultisol to Phosphorus Rates, Phosphorus Sources, and Filter Cake

    Directory of Open Access Journals (Sweden)

    Gustavo Caione

    2015-01-01

    Full Text Available We evaluated the effect of phosphorus application rates from various sources and in the presence or absence of filter cake on soil phosphorus, plant phosphorus, changes in acid phosphatase activity, and sugarcane productivity grown in Eutrophic Red Ultisol. Three P sources were used (triple superphosphate, Araxa rock phosphate, and Bayovar rock phosphate and four application rates (0, 90, 180, and 360 kg ha−1 of P2O5 in the presence or absence of filter cake (7.5 t ha−1, dry basis. The soil P, the accumulated plant P, the leaf acid phosphatase activity and straw, the stalk productivity, the concentration of soluble solids in the juice (Brix, the juice sucrose content (Pol, and the purity were the parameters evaluated. We found that P applications increased levels of soil, leaf, and juice phosphorus and led to higher phosphorus accumulation and greater stalk and straw productivity. These levels were highest in the presence of filter cake. Acid phosphatase activity decreased with increasing plant phosphorus concentration. Phosphate fertilization did not show effect on sugarcane technological quality. We concluded that P application, regardless of source, improved phosphorus nutrition and increased productivity in sugarcane and, when associated with filter cake, reduced the need for mineral fertilizer.

  11. Xingfa Group: To Be World-Famous Phosphorus Chemical Enterprise

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ As the biggest fine phosphorus chemical producer in China, Hubei Xingfa Chemicals Co., Ltd. (Xingfa Group, SH: 600141) is mainly engaged in the production and sales of phosphorus chemicals and fine chemicals.

  12. The release of dissolved phosphorus from lake sediments.

    OpenAIRE

    Boers, P.C.M.

    1991-01-01

    Chapter 1. Introduction: Eutrophication is one of the world's major water quality problems. Attempts to alleviate eutrophication of lakes have involved the control of phosphorus loadings. In such cases, an internal loading of phosphorus from the sediments may retard an improvement of the water quality. Chapters 2 - 5 deal specifically with the sediments of Lake Loosdrecht.Chapter 2. Distribution and forms of phosphorus in the sediments of the Loosdrecht Lakes (the Netherlands): The phosphorus...

  13. Results of activated sludge plants applying enhanced biological phosphorus removal

    Energy Technology Data Exchange (ETDEWEB)

    Machado, A.; Pinto, M.; Neder, K.; Hoffmann, H.

    1989-02-01

    To stop the eutrophication in lakes and rivers, the input of nutrient and phosphorus compounds must be limited. The biological elimination of phosphorus describes a possibility, to reduce phosphorus in the biological stage of a treatment plant to a considerable extent. In this paper the process-system and the operation-results of a pilot plant and two municipal treatment plants are presented, where biological phosphorus reduction about 80% takes place without any constructional modifications.

  14. Mechanical properties of low alloy high phosphorus weathering steel

    OpenAIRE

    Jena B.K.; Gupta N; Singh B; Ahoo G.S.

    2015-01-01

    Mechanical behaviour of two low alloy steels (G11 and G12) was studied with respect to different phosphorus contents. Tensile strength and yield strength increased while percentage elongation at fracture decreased on increasing phosphorus content. The SEM and light optical photomicrograph of low phosphorus steel (G11) revealed ferrite and pearlite microstructure. On increasing phosphorus content from 0.25 wt.% to 0.42 wt.%, the morphology of grain changed f...

  15. Response of Sugarcane in a Red Ultisol to Phosphorus Rates, Phosphorus Sources, and Filter Cake

    OpenAIRE

    Gustavo Caione; Renato de Mello Prado; Cid Naudi Silva Campos; Leandro Rosatto Moda; Ricardo de Lima Vasconcelos; João Martins Pizauro Júnior

    2015-01-01

    We evaluated the effect of phosphorus application rates from various sources and in the presence or absence of filter cake on soil phosphorus, plant phosphorus, changes in acid phosphatase activity, and sugarcane productivity grown in Eutrophic Red Ultisol. Three P sources were used (triple superphosphate, Araxa rock phosphate, and Bayovar rock phosphate) and four application rates (0, 90, 180, and 360 kg ha−1 of P2O5) in the presence or absence of filter cake (7.5 t ha−1, dry basis). The soi...

  16. Phosphorus, beverages, and chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Di Irorio B

    2012-10-01

    Full Text Available Biagio Di Iorio, Lucia Di Micco, Serena Torraca, Maria Luisa SiricoNephrology-Medicine Department, "A Landolfi" Hospital, Solofra, ItalyAbstract: Phosphate is present in food in two forms, ie, organic and inorganic phosphate salts, which are naturally present in food and as phosphates added for industrial and commercial reasons. There is also a high content of added phosphate in beverages, and phosphates in this form are highly absorbable. The real content of phosphate contained in beverages is often unrecognized, and nephrologists do not always take into account the amount of phosphorus that patients ingest in this form.Keywords: phosphorus, beverages, additive, diet

  17. Homogeneous phosphorus of silicon by neutron transmutation

    International Nuclear Information System (INIS)

    The manufacture of high-voltage power semiconductors requires a homogeneous phosphorus doping of silicon within extremely narrow limits. It was the aim of the investigations to develop neutron irradiation as a means to homogeneously dope silicon with phosphorus on an industrial scale. Special attention was given to the selection of suitable reactor positions, the annealing of the irradiation damage, and the electrical properties of the devices. The experience with the application of neutron irradiated silicon for a wide spectrum of devices shows that expected homogeneity and aiming accuracy with respect to the doping can be reached with high reliability. (orig.) 891 ORU/orig. 892 MB

  18. IMPROVING PHOSPHORUS NUTRITION OF COTTON

    Directory of Open Access Journals (Sweden)

    Walter B. Gordon

    2014-01-01

    Full Text Available Crop recovery of applied Phosphorus (P fertilizer can be low, especially during season of low soil temperature, which decreases plant root growth and nutrient uptake. The H2PO4- or HPO4-2 anions readily react with soil cations such as Calcium (Ca, Magnesium (Mg, iron (Fe and Aluminum (Al to produce various phosphate compounds of very limited water solubility. Specialty Fertilizer Products (SFP, Leawood, KS, USA has developed and patented a product registered as AVAIL® that is reported to attract and sequester antagonistic cations out of the soil solution leaving more of applied P in available form for plant uptake. To evaluate effectiveness of AVAIL product for cotton production, experiments were conducted in two locations in West Tennessee, Grand Junction (GJ in Hardeman County and Ames Plantation (AP located in Fayette County. Treatments consisted of applying Mono-Ammonium Phosphate (MAP, 11-52-0 alone or coated with AVAIL at rates of 34 or 68 kg ha-1 P2O5. A no P check was also included. An additional treatment consisting of AVAIL treated P in combination with Nutrisphere-N®, a Nitrogen (N stabilizer product offered by SFP, was also included. At GJ site, when averaged over P rates and years, AVAIL treated MAP improved tissue P concentration and increased cotton lint yield by 157 kg ha-1 over untreated MAP. At AP site, when averaged over years and P rates, application of AVAIL treated MAP increased cotton lint yield by 85 kg ha-1 over untreated MAP. In both experiments, 34 kg ha-1 AVAIL treated MAP produced higher tissue P concentrations and greater yields than 68 kg ha-1 without AVAIL. Influencing reactions in the micro-environment around the fertilizer granule has proven to have a significant benefit on the yield and P uptake of cotton. More research is needed to determine P content in the soil and further

  19. Phosphorus recovery as struvite from farm, municipal and industrial waste: Feedstock suitability, methods and pre-treatments.

    Science.gov (United States)

    Kataki, Sampriti; West, Helen; Clarke, Michèle; Baruah, D C

    2016-03-01

    Global population growth requires intensification of agriculture, for which a sustainable supply of phosphorus (P) is essential. Since natural P reserves are diminishing, recovering P from wastes and residues is an increasingly attractive prospect, particularly as technical and economic potential in the area is growing. In addition to providing phosphorus for agricultural use, precipitation of P from waste residues and effluents lessens their nutrient loading prior to disposal. This paper critically reviews published methods for P recovery from waste streams (municipal, farm and industrial) with emphasis on struvite (MgNH4PO4·6H2O) crystallisation, including pre-treatments to maximise recovery. Based on compositional parameters of a range of wastes, a Feedstock Suitability Index (FSI) was developed as a guide to inform researchers and operators of the relative potential for struvite production from each waste. PMID:26775756

  20. Phosphorus flows and balances of the European Union Member States

    NARCIS (Netherlands)

    Dijk, van K.C.; Lesschen, J.P.; Oenema, O.

    2015-01-01

    Global society faces serious “phosphorus challenges” given the scarcity, essentiality, unequal global distribution and, at the same time, regional excess of phosphorus (P). Phosphorus flow studies can be used to analyze these challenges, providing insight into how society (re)uses and loses phosphor

  1. 77 FR 46298 - Phosphorus Water Quality Standards for Florida Everglades

    Science.gov (United States)

    2012-08-03

    ... AGENCY 40 CFR Part 131 RIN 2040-AF38 Phosphorus Water Quality Standards for Florida Everglades AGENCY... provisions of Florida's Water Quality Standards for Phosphorus in the Everglades Protection Area (Phosphorus... are not applicable water quality standards for purposes of the Clean Water Act. EPA is...

  2. Reaching ultra low phosphorus concentrations by filtration techniques

    NARCIS (Netherlands)

    Scherrenberg, S.M.

    2011-01-01

    This research deals with tertiary treatment techniques used for the removal of phosphorus from wastewater treatment plant (WWTP) effluent. The main objective of this research is to obtain ultra low total phosphorus (<0.15 mg total phosphorus/L) concentrations by coagulation, flocculation and filtrat

  3. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for...

  4. Availability of phosphorus contained in poultry litter for lambs.

    Science.gov (United States)

    Tagari, H; Silanikove, N; Hurwitz, S

    1981-03-01

    Percentage net phosphorus availability (NPHA) and set phosphorus utilization (NPHU) of the phosphorus contained in a heat-sterilized poultry litter (PL) as compared to feed grade dicalcium phosphate (DCP) for lambs was assessed by the "slope" method. The method was based on the evaluation of the function of apparent phosphorus absorption (NPHA), or retention (NPHU), on phosphorus intake. Nitrogen retention was also evaluated. Plasma inorganic phosphorus concentration as a function of phosphorus intake was evaluated and compared to NPHA and NPHU. The percentage of NPHA was found to be 63.7 and 39, and that of NPHU was 63 and 38 for the phosphorus supplied by DCP and PL, respectively. Thus, the NPHA or NPHU for the phosphorus contained in PL is 60.9 and 60.3% of that of DCP, respectively. The slope ratio between the two phosphate supplements as observed for plasma inorganic phosphorus concentrations was similar to those found for NPHA and NPHU but the coefficient of variation was 5 times higher. Nitrogen digestibility was not affected by the level of phosphorus in the diets. Correlation between nitrogen retention and NPHA or NPHU was, however, significant (P less than 0.05). The slopes of dependence of N retention upon phosphorus intake were 2.81 and 1.6 (P less than 0.05) for DCP and PL treatments, respectively, and the ratio between the slopes was 0.57, close to the ratio of NPHU in PL to DCP-supplemented diets.

  5. PHOSPHORUS BIOGEOCHEMICAL CYCLING IN A SUGAR CANE AGROECOSYSTEM

    Directory of Open Access Journals (Sweden)

    D. Lopez-Hernandez

    2012-01-01

    Full Text Available The annual harvest of sugarcane plantations together with the burning of the crop before harvest, a common practice of management of sugarcane plantations in South America, leads to the loss of significant amounts of nutrients in those agroecosystems. Thus prescribed burning operations could progressively diminish the level of soil organic matter and increase nutrient deficiency in soils of sugar cane agrosystems. This study is an attempt to quantify the P distribution during the period of growth in a plantation of sugar cane (Saccharum officinarum located near San Felipe, Yaracuy State, Central, Venezuela focusing on processes related to the cycling of the element as affected by burning operations. The work was performed in 4.5 ha experimental plots planted with the varieties Puerto Rico (PR 1028 and Venezuela (V 58-4. The principal flows of phosphorus, as well the quantities of this element in the soil-plant components were measured throughout the growing cycle of the crop (third ratoon. The inputs through precipitation (wet and dry were high, that was associated with the intense agricultural (prescribed burning and industrial activities occurring in the area. The annual balance for both varieties was negative (-17.31 and -23.63 kg ha–1 for V 58-4 and PR 1028, respectively. The negative budget is mainly due to the important amounts of P that are exported with the cane stems. The losses must be compensated through fertilization; nonetheless, preliminary results indicated no response to P dressing, suggesting that in the studied mollisols the internal processes e.g., Organic-P (Po mineralization and P solubilization efficiently operate generating important available P levels. It was also found that the burning of the sugar cane plantation plays an important role in the recycling of phosphorus, since 25-28 % of the P requirements of the varieties are reincorporated into the soil from the ashes coming as bulk deposition.

  6. A simple approach to identify critical source areas for phosphorus leaching in the Netherlands

    Science.gov (United States)

    van der Salm, C.; Schoumans, O. F.; Walvoort, D.; Groenendijk, P.; Pleijter, M.

    2009-04-01

    High soil phopshorus contents in agricultural soils in the Netherlands cause excessive losses of P to surface waters. The reductions in P application rates in the present manure policy are not sufficient to reach surface water quality standards resulting from the European Water Framework Directive in all catchments by 2015. Accordingly, additional measures have to be considered to further reduce P loading to surface water. For a cost effective implementation of these measures an instrument to identify critical source areas for phosphorus leaching is indispensable. In the Netherlands phosphorus leaching at a national scale is simulated with a comprehensive mechanistic simulation model (STONE, Wolf et al., 2005) focusing on changes in P leaching with time. The identification of critical source areas requires simulations at a high spatial resolution. STONE is less suitable for this purpose, because of the large number of input parameters required by this complex model. For this reason, a simple model (PLEASE: Phosphorus LEAching from Soils to the Environment; Schoumans et al., in prep.) has been developed based on the same mechanistic process description for inorganic P as the complex model STONE and a simplified description of the lateral flow of water from soil to surface waters. With this model P leaching to surface waters can be calculated using readily available information of field characteristics like depth of the groundwater table, precipitation surplus and P status and phosphorus adsorption capacity of the soil. To evaluate the performance of the model, it was applied to the Netherlands using the same input as the national model. Parameterised in this way, PLEASE is a metamodel of STONE. The model was also tested on two small catchments: a catchment with sandy soils and high P accumulation and a clay catchment with a moderate P accumulation. The application at the national scale showed that the overall order of magnitude of the calculated leaching fluxes was

  7. Closing the Phosphorus Loop by Recovering Phosphorus From Waste Streams With Layered Double Hydroxide Nanocomposites and Converting the Product into an Efficient Fertilizer

    Science.gov (United States)

    Yan, H.; Shih, K.

    2015-12-01

    Phosphorus (P) recovery has been frequently discussed in recent decades due to the uncertain availability and uneven distribution of global phosphate rock reserves. Sorption technology is increasingly considered as a reliable, efficient and environmentally friendly P removal method from aqueous solution. In this study, a series of Mg-Al-based layered double hydroxide nanocomposites and their corresponding calcined products were fabricated and applied as phosphate adsorbents. The prepared samples were with average size at ~50 nm and self-assembled into larger particles in irregular shapes. The results of batch adsorption experiments demonstrated that calcination significantly enhanced the adsorption ability of LDHs for phosphorus, and the maximum adsorption capacity of calcined Mg-Al-LDH was as high as 100.7 mg-P/g. Furthermore, incorporation of Zr4+ and La3+ into LDH materials increases the sorption selectivity as well as sorption amount of phosphorus in LDHs, which was confirmed by experiments operated in synthetic human urine. For the first time ammonia (NH4OH) and potassium hydroxide (KOH) solutions were employed to desorb the P-loaded LDH. Identification of solids derived from two eluting solutions showed that struvite (MgNH4PO4•6H2O, MAP) was precipitated in ammonia solution while most phosphate was desorbed into liquid phase in KOH system without crystallization of potassium struvite (MgKPO4•6H2O) due to its higher solubility. Quantitative X-ray diffraction technique was used to determine struvite contents in obtained solids and the results revealed that ~ 30% of adsorbed P was transferred into struvite form in the sample extracted by 0.5M NH4OH. Leaching tests suggested that the phosphorus releasing kinetics of ammonia treated LDH was comparable to that of pure struvite product, indicating that postsorption Mg-Al-LDH desorbed with ammonia could serve as a slow-releasing fertilizer in agriculture (see Figure 1).

  8. Agricultural Libraries and Information.

    Science.gov (United States)

    Russell, Keith W., Ed.; Pisa, Maria G., Ed.

    1990-01-01

    Eleven articles address issues relating to agricultural libraries and information, including background on agricultural libraries and information, trend management, document delivery, reference services, user needs and library services, collection development, technologies for international information management, information sources,…

  9. Innovations in urban agriculture

    NARCIS (Netherlands)

    Schans, van der J.W.; Renting, Henk; Veenhuizen, Van René

    2014-01-01

    This issuehighlights innovations in urban agriculture. Innovation and the various forms of innovations are of particular importance because urban agriculture is adapted to specific urban challenges and opportunities. Innovation is taking place continuously, exploring the multiple fundions of urban a

  10. Agricultural science policy

    OpenAIRE

    Alston, Julian M.; Pardey, Philip G.; Taylor, Michael J.

    2001-01-01

    Technological advances developed through R&D have supplied the world with not only more food, but better food. This report looks at issues raised by this changing environment for agricultural productivity, agricultural R&D, and natural resource management.

  11. Traditional Agriculture and Permaculture.

    Science.gov (United States)

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate cultural…

  12. Urban Agricultural Education.

    Science.gov (United States)

    Corbellini, Margaret

    1991-01-01

    John Bourne High School in Queens, New York, offers an agricultural program enrolling more than 400 students. The curriculum includes agricultural career exploration, plant and animal science, summer land laboratories, and a special education component. (SK)

  13. Agricultural policy schemes

    DEFF Research Database (Denmark)

    Hansen, Henning Otte

    2016-01-01

    of direct support, while market prices are left undistorted at, or close to, world market level. The two different support systems have very different implications for agricultural production, financing, markets, and other aspects; still, there is an income transfer to agriculture in both systems. During......Agricultural support is a very important element in agricultural policy in many countries. Agricultural support is basically an instrument to meet the overall objectives of the agricultural policy – objectives set by society. There are a great number of instruments and ways of intervention...... in agricultural policy and they have different functions and impacts. Market price support and deficiency payments are two very important instruments in agricultural policy; however, they belong to two different support regimes or support systems. Market price support operates in the so-called high price system...

  14. Synchronous Upgrading Iron and Phosphorus Removal from High Phosphorus Oolitic Hematite Ore by High Temperature Flash Reduction

    OpenAIRE

    Deqing Zhu; Zhengqi Guo; Jian Pan; Feng Zhang

    2016-01-01

    In this paper, an effective method was developed to remove phosphorus and upgrade iron from high phosphorus oolitic hematite ore by high temperature flash reduction—a wet magnetic separation process. A thermodynamic analysis of iron and phosphorus mineral reactions and experiments with Fe-P separation process were performed, and the mechanism of phosphorus removal and beneficiation of iron is discussed as well. The results show that under the proper conditions, a final metallic iron powder as...

  15. On-farm assessment of laying hen welfare: a comparison of one environment-based and two animal-based methods

    NARCIS (Netherlands)

    Mollenhorst, H.; Rodenburg, T.B.; Bokkers, E.A.M.; Koene, P.; Boer, de I.J.M.

    2005-01-01

    Methods available to assess animal welfare at farm level are based on a range of welfare parameters, which can be divided into two categories, environment-based and animal-based parameters. The first category describes features of the environment and management, which can be considered prerequisites

  16. Impacts of European livestock production: nitrogen, sulphur, phosphorus and greenhouse gas emissions, land-use, water eutrophication and biodiversity

    OpenAIRE

    Leip, Adrian; Billen, Gilles; Garnier, Josette; Grizzetti, Bruna; LASSALETTA, LUIS; Reis, Stefan; Simpson, David; Sutton, Mark A.; Vries, Wim de; Weiss, Franz; Westhoek, Henk

    2015-01-01

    International audience Livestock production systems currently occupy around 28% of the land surface of the European Union (equivalent to 65% of the agricultural land). In conjunction with other human activities, livestock production systems affect water, air and soil quality, global climate and biodiversity, altering the biogeochemical cycles of nitrogen, phosphorus and carbon. Here, we quantify the contribution of European livestock production to these major impacts. For each environmenta...

  17. Impacts of European livestock production: nitrogen, sulphur, phosphorus and greenhouse gas emissions, land-use, water eutrophication and biodiversity

    OpenAIRE

    Leip, Adrian; Billen, Gilles; Garnier, Josette; Grizzetti, Bruna; LASSALETTA, LUIS; Reis, Stefan; Simpson, David; Sutton M A; W. De Vries; WEISS FRANZ; Westhoek, H.J.

    2015-01-01

    Livestock production systems currently occupy around 28% of the land surface of the European Union (equivalent to 65% of the agricultural land). In conjunction with other human activities, livestock production systems affect water, air and soil quality, global climate and biodiversity, altering the biogeochemical cycles of nitrogen, phosphorus and carbon. Here, we quantify the contribution of European livestock production to these major impacts. For each environmental effect, the contribution...

  18. Process-based modelling of phosphorus removal in a novel constructed wetland system using dewatered alum-sludge as substrate

    OpenAIRE

    Kumar, J.L.G.; Zhao, Y.Q.; Babatunde, A.O.

    2011-01-01

    A process-based model that can evaluate the transport and the fate of phosphorus (P) in agricultural wastewater was developed for a novel 4-stage dewatered alum sludge cakes (DASC) based constructed wetlands (CWs) system using STELLA software (version 9.1.4). The model considered adsorption, plant and microbial uptakes as the major forms of P involved in the transformation chains. The results were obtained by experimental procedure through laboratory measurement, from literature and/or calibr...

  19. BOOK REVIEWS - Precision agriculture

    OpenAIRE

    Stanisław Samborski; Dariusz Gozdowski

    2007-01-01

    Precision agriculture (PA) is a term, which has recently become very popular in agronomy. In short this term means crop production based on site-specific crop management (SSCM). Precision agriculture is an integrated agricultural management system incorporating different science disciplines e.g. crop science, agricultural engineering and geostatistics. It also uses numerous tools i.e., geographic information system (GIS), Global Positioning System (GPS), remote sensing yield monitors. Because...

  20. Innovations in urban agriculture

    OpenAIRE

    Schans, van der, D.A.; Renting, Henk; Veenhuizen, van, R.

    2014-01-01

    This issuehighlights innovations in urban agriculture. Innovation and the various forms of innovations are of particular importance because urban agriculture is adapted to specific urban challenges and opportunities. Innovation is taking place continuously, exploring the multiple fundions of urban agriculture, including food security, income generation and environmental management.

  1. Engaging Stakeholders To Define Feasible and Desirable Agricultural Conservation in Western Lake Erie Watersheds.

    Science.gov (United States)

    Kalcic, Margaret McCahon; Kirchhoff, Christine; Bosch, Nathan; Muenich, Rebecca Logsdon; Murray, Michael; Griffith Gardner, Jacob; Scavia, Donald

    2016-08-01

    Widespread adoption of agricultural conservation measures in Lake Erie's Maumee River watershed may be required to reduce phosphorus loading that drives harmful algal blooms and hypoxia. We engaged agricultural and conservation stakeholders through a survey and workshops to determine which conservation practices to evaluate. We investigated feasible and desirable conservation practices using the Soil and Water Assessment Tool calibrated for streamflow, sediment, and nutrient loading near the Maumee River outlet. We found subsurface placement of phosphorus applications to be the individual practice most influential on March-July dissolved reactive phosphorus (DRP) loading from row croplands. Perennial cover crops and vegetated filter strips were most effective for reducing seasonal total phosphorus (TP) loading. We found that practices effective for reducing TP and DRP load were not always mutually beneficial, culminating in trade-offs among multiple Lake Erie phosphorus management goals. Adoption of practices at levels considered feasible to stakeholders led to nearly reaching TP targets for western Lake Erie on average years; however, adoption of practices at a rate that goes beyond what is currently considered feasible will likely be required to reach the DRP target. PMID:27336855

  2. Changes of water quality and sediment phosphorus of a small productive lake following decreased phosphorus loading

    OpenAIRE

    Heaney, S. I.; Corry, J.E.; Lishman, J.P.

    1992-01-01

    Esthwaite Water is the most productive or eutrophic lake in the English Lake District. Since 1945 its water quality has been determined from weekly or biweekly measurements of temperature, oxygen, plant nutrients and phytoplankton abundance. The lake receives phosphorus from its largely lowland-pasture catchment, sewage effluent from the villages of Hawkshead and Near Sawrey, and from a cage-culture fish farm. From 1986 phosphorus has been removed from the sewage effluent of Hawkshead which w...

  3. Lake Erie phosphorus loading and Cladophora updates

    Science.gov (United States)

    The presentation will focus on updates or progress being made on each Phosphorus Loadings and Cladophora for Lake Erie. The format will give a brief summary of data, findings, and results that were used by the Great Lakes Water Quality Agreement (GLWQA) Annex 4 Nutrients Modeli...

  4. Phosphorus recycling from the waste sector

    NARCIS (Netherlands)

    Ruijter, de F.J.; Dijk, Van W.; Curth-van Middelkoop, J.C.; Reuler, van H.

    2015-01-01

    An efficient use of phosphorus (P) is necessary as phosphate rock is a finite resource and P is essential for crop production. From the waste sector in the Netherlands, 23 Mkg P is sequestered in landfill, incineration ashes and cement. Flows containing P are discussed, together with options to reco

  5. Stewardship to tackle global phosphorus inefficiency

    NARCIS (Netherlands)

    Withers, P.J.A.; Dijk, van K.C.; Neset, T.S.S.; Nesme, Thomas; Oenema, Oene; Rubæk, G.H.; Schoumans, O.F.; Smit, Bert; Pellerin, Sylvain

    2015-01-01

    The inefficient use of phosphorus (P) in the food chain is a threat to the global aquatic environment and the health and well-being of citizens, and it is depleting an essential finite natural resource critical for future food security and ecosystem function. We outline a strategic framework of 5

  6. Nanotubes based on monolayer blue phosphorus

    KAUST Repository

    Montes, E.

    2016-07-08

    We demonstrate structural stability of monolayer zigzag and armchair blue phosphorus nanotubes by means of molecular dynamics simulations. The vibrational spectrum and electronic band structure are determined and analyzed as functions of the tube diameter and axial strain. The nanotubes are found to be semiconductors with a sensitive indirect band gap that allows flexible tuning.

  7. Phosphate recycling in the phosphorus industry

    NARCIS (Netherlands)

    Schipper, W.J.; Klapwijk, A.; Potjer, A.; Rulkens, W.H.; Temmink, B.G.; Kiestra, F.D.G.; Lijmbach, A.C.M.

    2001-01-01

    The feasibility of phosphate recycling in the white phosphorus production process is discussed. Several types of materials may be recycled, provided they are dry inorganic materials, low in iron, copper and zinc. Sewage sludge ash may be used if no iron is used for phosphate precipitation in the tre

  8. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

    Atienza-Martinez, M.; Gea, G.; Arauzo, J.; Kersten, S.R.A.; Kootstra, A.M.J.

    2014-01-01

    Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C and 900 °C) and after gasification (at 820 °C using a mixture of air and steam as fluidising agent) of char from sewage sludge fast pyrolysis carried out at 530 °C. Depending on the leaching con

  9. A Consideration of Agriculture and Agricultural Science

    Institute of Scientific and Technical Information of China (English)

    Liu Gengling

    2006-01-01

    The article explores the importance of agricultulture in line with development of society. It uses examples of high productivity achieved in grain and cotton crops in lnner Mongolia and Xinjiang areas to show that the fundamental objective of agricultural science is to maximize crops through the most effective use of soil, fertilizer and water in gaining the greatest benefit from power of the sun. Agricultural science should take up relevant theories and methodologies from other sciences, such as biological science, earth science and economics. The use of information technology will have great benefits for agricultural science. It hopes the scientific communities of China can make a significant contribution to solving the problems facing our rural areas, farmers and agriculture itself.

  10. Temperature-dependant study of phosphorus ion implantation in germanium

    Science.gov (United States)

    Razali, M. A.; Smith, A. J.; Jeynes, C.; Gwilliam, R. M.

    2012-11-01

    We present experimental results on shallow junction formation in germanium by phosphorus ion implantation and standard rapid thermal processing. An attempt is made to improve phosphorus activation by implanting phosphorus at high and low temperature. The focus is on studying the germanium damage and phosphorus activation as a function of implant temperature. Rutherford backscattering spectrometry with channelling and Hall Effect measurements are employed for characterisation of germanium damage and phosphorus activation, respectively. High and low temperature implants were found to be better compared to room temperature implant.

  11. AGRICULTURAL POLICIES AND COMPETITION IN WORLD AGRICULTURE

    Directory of Open Access Journals (Sweden)

    Raluca Duma

    2011-04-01

    Full Text Available Agricultural policies have had a guiding role inagriculture development and implicitly in their marketing. Usually they belongto each state and government and are issued in accordance with their specificclimate, social-economic and cultural background which includes food andgastronomic traditions. Agricultural policies have in view home and foreignmarket demand, as well as the socio-demographic, political and military contextat a certain point in the socio-economic development

  12. Determination of phosphorus fertilizer soil reactions by Raman and synchrotron infrared microspectroscopy.

    Science.gov (United States)

    Vogel, Christian; Adam, Christian; Sekine, Ryo; Schiller, Tara; Lipiec, Ewelina; McNaughton, Don

    2013-10-01

    The reaction mechanisms of phosphate-bearing mineral phases from sewage sludge ash-based fertilizers in soil were determined by Raman and synchrotron infrared microspectroscopy. Different reaction mechanisms in wet soil were found for calcium and magnesium (pyro-) phosphates. Calcium orthophosphates were converted over time to hydroxyapatite. Conversely, different magnesium phosphates were transformed to trimagnesium phosphate. Since the magnesium phosphates are unable to form an apatite structure, the plant-available phosphorus remains in the soil, leading to better growth results observed in agricultural pot experiments. The pyrophosphates also reacted very differently. Calcium pyrophosphate is unreactive in soil. In contrast, magnesium pyrophosphate quickly formed plant-available dimagnesium phosphate. PMID:24067573

  13. Phosphorus reduction by sifting fish waste meal

    Directory of Open Access Journals (Sweden)

    Ronaldo Lima de Lima

    2014-10-01

    Full Text Available Fish meal is widely included in animal feed because it contains ideal essential amino acids profile, it is rich in energy, essential fatty acids, vitamins and minerals and with >80% apparent protein digestibility in peneid shrimp. In human nutrition, studies are investigating the inclusion of fish meal in snacks, cakes, breads and cookies, as an enrichment in calcium, phosphorus, iron, protein and, especially, omega-3 fatty acids. Omega-3 fatty acids reduces heart diseases and have antithrombotic and anti-inflammatory properties (eicosapentaenoic acid, and are essential to the formation of brain tissue and retina in infants and are important during pregnancy and lactation (docosahexaenoic acid. Fish meal produced from fish waste is rich in minerals (phosphorus, which may cause eutrophication and impair water quality in aquaculture. The aim of this study was to reduce phosphorus content from commercial fish meal produced from waste by sifting (0.60 - 1.00 - 1.18 - 1.40 - 2.36 and 3.35mm mesh sizes. Fish meal samples were collected monthly for 24 months. Proximate composition of subsamples per mesh size was compared to the unsieved sample. Results indicate that sifting through a 0.60mm sieve total phosphorus and ash contents were reduced up to 32% and 36%, respectively, further to increase protein content up to 20%. Average composition of the subsamples was 47.04% ash, 5.56% of total phosphorus and 39.45% protein, suggesting that the residue of the fractionation may be marketed as a mineral and protein supplement.

  14. Goats Rearing Under Islamic Teachings and its Profitable Impact on Agricultural Economics

    OpenAIRE

    Abad-ur-Rahman; Syed Naeem Badshah; Janas Khan; Muhammad Ayaz

    2012-01-01

    This article is written on goat rearing animal based agricultural economy, Goats rearing has been given preferences and admitted as source of to end poverty and assorted blessing as mentioned in Hadith. Because blessing Barakat means increase. Therefore goat has got such characteristic to give enhance breeding. For example, goat has the potential to give birth one to three offspring twice a year. It has been examined that goat breeds one to three offsprings twice a year; in this way a goat br...

  15. Impact of Fish Farming on Phosphorus in Reservoir Sediments

    Science.gov (United States)

    Jia, Binyang; Tang, Ya; Tian, Liyan; Franz, Leander; Alewell, Christine; Huang, Jen-How

    2015-11-01

    Fish farming has seriously influenced the aquatic environment in Sancha reservoir in SW China since 1985 and has been strongly restricted since 2005. Thus, phosphorus speciation in a sediment core dated between 1945 and 2010 at cm-resolution and in surface sediments from Sancha reservoir may allow us track how fish farming impacts phosphorus dynamics in lake sediments. Fish farming shifts the major binding forms of phosphorus in sediments from organic to residual phosphorus, which mostly originated from fish feed. Sorption to metal oxides and association with organic matters are important mechanisms for phosphorus immobilisation with low fish farming activities, whereas calcium-bound phosphorous had an essential contribution to sediment phosphorus increases under intensive fish framing. Notwithstanding the shifting, the aforementioned phosphorus fractions are usually inert in the lake environment, therefore changing phosphorus mobility little. The use of fish feed and water-purification reagents, the most important additives for fish farming, introduce not only phosphorus but also large amounts of sand-sized minerals such as quartz into the lake, to which phosphorus weakly sorbs. The sand-sized minerals as additional sorbents increase the pool of easily mobilisable phosphorus in sediments, which will slow down the recovery of reservoir water due to its rapid re-mobilisation.

  16. Reviews on Phosphorus Surplus of Cultivated Land%耕地磷盈余研究进展

    Institute of Scientific and Technical Information of China (English)

    徐梦; 吴胜军; 张亮; 刘睿; 冯奇

    2012-01-01

    Phosphorus has caused universal concern as a key factor of eutrophication. Cultivated lands with phosphorus surplus are important source of nonpoint source pollution. Phosphorus surplus has been reviewed in three ways in this paper;the amount of phosphorus surplus all around the world,the risk assessment of phophorus surplus and the mitigation of phosphorus surplus. The study shows that phosphorus surplus in cultivated land has become a serious issue all around the world. The amount of phosphorus surplus is increasing in China, while in many developed countries it is decreasing. The risk of phosphorus surplus mainly lays in the loss of phosphorus from land to water. Optimized fertilization , crop type, farm land management and type of agriculture could be effective mitigation of phosphourus surplus.%磷作为影响水体富营养化的关键因素之一,已受到人们的普遍关注.磷盈余的耕地是水体磷的重要来源.本文从国内外耕地磷盈余量、耕地磷盈余的环境风险及其防治三个方面对目前耕地磷盈余的研究进行了综述.研究表明,随着农业的发展,化肥投入的增加,磷盈余问题普遍存在于世界各地,我国耕地磷盈余正处于上升通道,大多数发达国家则处于控制下降通道;耕地磷盈余的环境风险主要表现为耕地磷流失能力以及区域非点源磷污染的可能性;通过改良施肥方式、优化作物类型、加强田间管理模式及改进农业类型能够有效减少磷盈余带来的危害.

  17. Effects of different phosphorus and potassium fertilization on contents and uptake of macronutrients (N, P, K, Ca, Mg in winter wheat I. Content of macronutrients

    Directory of Open Access Journals (Sweden)

    Renata GAJ

    2014-12-01

    Full Text Available The aim of the study carried out under field conditions was to evaluate the effect of differentiated phosphorus and potassium fertilization level on nutritional status of winter wheat at stem elongation (BBCH 31 and flowering (BBCH 65 development stages as well as on macronutrient contents in yield obtained (grain and straw. The research was conducted in 2007-2010, within an individual agricultural holding, on lessive soil with medium and high richness in potassium and phosphorus, respectively. The contents of nitrogen, phosphorus, potassium, magnesium and calcium in wheat changed depending on the organ assessed and plant development stage. At BBCH 31, regardless fertilization level, the plants observed were malnourished with potassium, phosphorus and calcium and at the control site also with nitrogen. Furthermore, there were found significant correlation relationships among the contents of nutrient pairs: nitrogen-potassium, nitrogen-phosphorus, nitrogen-magnesium and nitrogen-calcium. The content of nitrogen in wheat grain and straw differed mainly due to weather conditions during the study. Irrespective of the years of observation, differentiated rates of P and K applied had no significant effect on N accumulation in wheat at full ripening stage. In contrast to nitrogen, the level of P and K fertilization significantly differentiated the contents of phosphorus, potassium and magnesium in wheat grain and straw. In case of calcium, the effect of fertilization factor was indicated only as regards the content of this nutrient in grain.

  18. Eutrophication study at the Panjiakou-Daheiting Reservoir system, northern Hebei Province, People's Republic of China: Chlorophyll-a model and sources of phosphorus and nitrogen

    Science.gov (United States)

    Domagalski, J.; Lin, C.; Luo, Y.; Kang, Jie; Wang, Shaoming; Brown, L.R.; Munn, M.D.

    2007-01-01

    Concentrations, loads, and sources of nitrate and total phosphorus were investigated at the Panjiakou and Daheiting Reservoir system in northern Hebei Province, People's Republic of China. The Luan He River is the primary source of water to these reservoirs, and the upstream watershed has a mix of land uses including agriculture, forest, and one large urban center. The reservoirs have a primary use for storage of drinking water and partially supply Tianjin City with its annual needs. Secondary uses include flood control and aqua culture (fish cages). The response of the reservoir system from phosphorus input, with respect to chlorophyll-a production from algae, was fitted to a model of normalized phosphorus loading that regresses the average summer-time chlorophyll-a concentration to the average annual phosphorus concentration of the reservoir. Comparison of the normalized phosphorus loading and chlorophyll-a response of this system to other reservoirs throughout the world indicate a level of eutrophication that will require up to an approximate 5-10-fold decrease in annual phosphorus load to bring the system to a more acceptable level of algal productivity. Isotopes of nitrogen and oxygen in dissolved nitrate were measured from the headwater streams and at various locations along the major rivers that provide the majority of water to these reservoirs. Those isotopic measurements indicate that the sources of nitrate change from natural background in the rivers to animal manure and septic waste upstream of the reservoir. Although the isotopic measurements suggest that animal and septic wastes are a primary source of nutrients, measurements of the molar ratio of nitrogen to phosphorus are more indicative of row-cropping practices. Options for reduction of nutrient loads include changing the management practices of the aqua culture, installation of new sewage treatment systems in the large urbanized area of the upper watershed, and agricultural management practices

  19. Eutrophication Study at the Panjiakou-Daheiting Reservoir System, Northern Hebei Province, People's Republic of China: Chlorophyll-a Model and Sources of Phosphorus and Nitrogen

    Science.gov (United States)

    Domagalski, J.; Lin, C.; Luo, Y.; Kang, J.; Wang, S.; Brown, L.; Munn, M.

    2007-05-01

    Concentrations, loads, and sources of nitrate and total phosphorus were investigated at the Panjiakou and Daheiting Reservoir system in northern Hebei Province, People's Republic of China. The Luan He River is the primary source of water to these reservoirs, and the upstream watershed has a mix of land uses including agriculture, forest, with one large urban center. The reservoirs have a primary use for storage of drinking water and partially supply Tianjin City with its annual needs. Secondary uses include flood control and aqua culture (fish cages). The response of the reservoir system from phosphorus input, with respect to chlorophyll-a production from algae, was fitted to a model of normalized phosphorus loading that regresses the average summer-time chlorophyll-a concentration to the average annual phosphorus concentration of the reservoir. Comparison of the normalized phosphorus loading and chlorophyll-a response of this system to other reservoirs throughout the world indicate a level of eutrophication that will require up to an approximate 10-fold decrease in annual phosphorus load to bring the system to a more acceptable level of algal productivity. Isotopes of nitrogen and oxygen in dissolved nitrate were measured from the headwater streams and at various locations along the major rivers that provide the majority of water to these reservoirs. Those isotopic measurements indicate that the sources of nitrate change from natural background in the rivers to animal manure and septic waste upstream of the reservoir. Although the isotopic measurements suggest that animal and septic wastes are a primary source of nutrients, measurements of the molar ratio of nitrogen to phosphorus are more indicative of row-cropping practices. Options for reduction of nutrient loads include changing the management practices of the aqua culture, installation of new sewage treatment systems, especially in the one major urbanized area of the upper watershed, and agricultural

  20. Recovery of agricultural nutrients from biorefineries.

    Science.gov (United States)

    Carey, Daniel E; Yang, Yu; McNamara, Patrick J; Mayer, Brooke K

    2016-09-01

    This review lays the foundation for why nutrient recovery must be a key consideration in design and operation of biorefineries and comprehensively reviews technologies that can be used to recover an array of nitrogen, phosphorus, and/or potassium-rich products of relevance to agricultural applications. Recovery of these products using combinations of physical, chemical, and biological operations will promote sustainability at biorefineries by converting low-value biomass (particularly waste material) into a portfolio of higher-value products. These products can include a natural partnering of traditional biorefinery outputs such as biofuels and chemicals together with nutrient-rich fertilizers. Nutrient recovery not only adds an additional marketable biorefinery product, but also avoids the negative consequences of eutrophication, and helps to close anthropogenic nutrient cycles, thereby providing an alternative to current unsustainable approaches to fertilizer production, which are energy-intensive and reliant on nonrenewable natural resource extraction. PMID:26948442

  1. Effect of Carbon on Grain Boundary Segregation of Phosphorus and Phosphorus-Induced Intergranular Fracture in High Purity Iron with Phosphorus

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The segregation of carbon at grain boundaries and its effect on phosphorus segregation and phosphorus-induced intergranular fracture in the alloy of high purity iron with phosphorus were investigated by scanning Auger electron spectroscopy, impact test and SEM observation of fractured surface. The experimental results showed that the carbon segregation at grain boundaries decreases the phosphorus segregation, and a change of fracture mode from intergranular fracture to transgranular one, hence a decrease of ductile-brittle transition temperature is observed. The mechanism of these effects was discussed.

  2. Potential Impact of Dietary Choices on Phosphorus Recycling and Global Phosphorus Footprints: The Case of the Average Australian City

    Science.gov (United States)

    Metson, Geneviève S.; Cordell, Dana; Ridoutt, Brad

    2016-01-01

    Changes in human diets, population increases, farming practices, and globalized food chains have led to dramatic increases in the demand for phosphorus fertilizers. Long-term food security and water quality are, however, threatened by such increased phosphorus consumption, because the world’s main source, phosphate rock, is an increasingly scarce resource. At the same time, losses of phosphorus from farms and cities have caused widespread water pollution. As one of the major factors contributing to increased phosphorus demand, dietary choices can play a key role in changing our resource consumption pathway. Importantly, the effects of dietary choices on phosphorus management are twofold: First, dietary choices affect a person or region’s “phosphorus footprint” – the magnitude of mined phosphate required to meet food demand. Second, dietary choices affect the magnitude of phosphorus content in human excreta and hence the recycling- and pollution-potential of phosphorus in sanitation systems. When considering options and impacts of interventions at the city scale (e.g., potential for recycling), dietary changes may be undervalued as a solution toward phosphorus sustainability. For example, in an average Australian city, a vegetable-based diet could marginally increase phosphorus in human excreta (an 8% increase). However, such a shift could simultaneously dramatically decrease the mined phosphate required to meet the city resident’s annual food demand by 72%. Taking a multi-scalar perspective is therefore key to fully exploring dietary choices as one of the tools for sustainable phosphorus management. PMID:27617261

  3. Potential Impact of Dietary Choices on Phosphorus Recycling and Global Phosphorus Footprints: The Case of the Average Australian City.

    Science.gov (United States)

    Metson, Geneviève S; Cordell, Dana; Ridoutt, Brad

    2016-01-01

    Changes in human diets, population increases, farming practices, and globalized food chains have led to dramatic increases in the demand for phosphorus fertilizers. Long-term food security and water quality are, however, threatened by such increased phosphorus consumption, because the world's main source, phosphate rock, is an increasingly scarce resource. At the same time, losses of phosphorus from farms and cities have caused widespread water pollution. As one of the major factors contributing to increased phosphorus demand, dietary choices can play a key role in changing our resource consumption pathway. Importantly, the effects of dietary choices on phosphorus management are twofold: First, dietary choices affect a person or region's "phosphorus footprint" - the magnitude of mined phosphate required to meet food demand. Second, dietary choices affect the magnitude of phosphorus content in human excreta and hence the recycling- and pollution-potential of phosphorus in sanitation systems. When considering options and impacts of interventions at the city scale (e.g., potential for recycling), dietary changes may be undervalued as a solution toward phosphorus sustainability. For example, in an average Australian city, a vegetable-based diet could marginally increase phosphorus in human excreta (an 8% increase). However, such a shift could simultaneously dramatically decrease the mined phosphate required to meet the city resident's annual food demand by 72%. Taking a multi-scalar perspective is therefore key to fully exploring dietary choices as one of the tools for sustainable phosphorus management. PMID:27617261

  4. Phosphorus Forms in Ultisol Submitted to Burning and Trituration of Vegetation in Eastern Amazon

    Directory of Open Access Journals (Sweden)

    Samuel Christian Cohen Farias

    2016-01-01

    Full Text Available ABSTRACT The use of fire to prepare agricultural areas is a technique still used by small farmers in eastern Amazon. This type of management changes the dynamics of soil nutrients, especially phosphorus, which constitutes the most limiting nutrient for crop production in tropical soils. This study was carried out to evaluate changes in phosphorus forms in an Argissolo Amarelo Distrófico (Ultisol submitted to burning and trituration of secondary forest in eastern Amazon. The evaluated systems were: slash-and-burn of vegetation; slash-and-mulch of vegetation; and secondary vegetation. The labile, moderately labile, moderately recalcitrant, available and total phosphorus fractions were assessed at the soil depths of 0.00-0.05, 0.05-0.10 and 0.10-0.20 m. The results showed a predominance of soluble P in acid (moderately labile P over other forms in all management systems. The management systems influence the content and distribution of the forms of P, where the slash-and-mulch system presented the prevalence of the labile fraction, and the slash-and-burn system contained less labile forms. The slash-and-mulch system favored the accumulation of labile P and total organic P.

  5. Study of The Maximum Uptake Capacity on Various Sizes of Electric Arc Furnace Slag in Phosphorus Aqueous Solutions

    Science.gov (United States)

    Afnizan, W. M. W.; Hamdan, R.; Othman, N.

    2016-07-01

    The high content of uncontrolled phosphorus concentration in wastewater has emerged as a major problem recently. The excessive amount of phosphorus that is originated from domestic waste, unproper treated waste from septic tanks, as well as agricultural activities have led to the eutrophication problem. Therefore, a laboratory experiment was initiated to evaluate the potential of the Electric Arc Furnace Slag (EAFS), a by-product waste from steel making industry in removing phosphorus concentrations in aqueous solutions. In this work several particle sizes ranging from (9.5-12.4 mm, 12.5-15.9 mm, 16.0-19.9 mm, 20.0-24.9 mm, 25-37.4 mm) with a known weight (20±0.28 g, 40±0.27 g, 60±0.30 g, 80±0.29 g and 100±0.38 g) were used to study the effect of different particle sizes towards phosphorus removal. Each particle size of EAFS was shaken in synthetic phosphorus solutions (10 mg/l, 20 mg/l, 30 mg/l, 40 mg/l and 50 mg/l) at a contact time of 2 hours. Final concentrations of phosphorus were sampled and the measurement was made using WESTCO Discrete Analyzer equipment. Results showed that the highest of the maximum uptake capacity of each EAFS particle size distribution achieved at 0.287, 0.313, 0.266, 0.241 and 0.25 mg/g as particle size range was varied from 9.5-12.4 mm to 25-37.4 mm. In conclusion, the maximum uptake capacity of each EAFS mostly was determined to occur at adsorbent weight of 20 to 40 g in most conditions.

  6. Reorganization of Agricultural Extension toward Green Agriculture

    Directory of Open Access Journals (Sweden)

    Mohammad S. Allahyari

    2009-01-01

    Full Text Available Problem statement: Considering unsustainable agricultural conditions of Iran and organizational recession and inability of current extension organization to achieve sustainability, it seems that extension systems require a new organizational structure to achieve sustainability objectives. The purpose of the present study was to identify the most appropriate characteristics for extension organization toward green agriculture in Iran context. Approach: To fulfill this objective, a sample of 120 respondents was selected through simple random sampling technique. A survey study was applied as a methodology of research. A mailed questionnaire was used to collect the data. The response rate of questionnaire was 65.83% (N = 79. Appropriate descriptive statistics such as mean scores, standard deviations and variation ratio were used. Results: Extension experts believed that among important organizational characteristics of extension system for supporting green agriculture collaboration among research, extension, education organizations, farmers' associations, NGOs, rural credit agencies, transportation companies, considering local groups and learning organization had very high importance for supporting green agriculture. According to factor analysis, the implications for extension organization were categorized into two groups consisting: (1 Holistic organizations (2 Participatory organizations that those factors explained 67.54% of the total variance of the research variables. Conclusion: Identifying suitable extension mechanisms had important role for developing extension system. Therefore, identifying extension organizational characteristics for supporting green agriculture of Iran is one of the major approaches needs to be carefully thought and accurately implemented for the extension system development.

  7. MODERNIZATION OF AGRICULTURE VS SUSTAINABLE AGRICULTURE

    Directory of Open Access Journals (Sweden)

    Dariusz KUSZ

    2014-04-01

    Full Text Available The paper shows the correlation between the need to modernise agriculture and sustainable development. Modernisation of agriculture aiming only at increasing the efficiency of production, if implemented in accordance with the principles of sustainable development, enabled reduction in the negative external effects. Modernisation of agriculture is supposed to ensure productivity growth without imposing any threats to the natural environment and the well-being of animals, reduced impoverishment in rural areas as well as to ensure food security, growth in the profitability of farms, improvement to the efficiency of use of natural resources. Therefore, in the near future, the agriculture – environment relation will be subject to change taking into account, on the one hand, concern about the natural environment, and, on the other, pressure on increasing the efficiency of production. The above challenges will be addressed by the need to implement efficient and, at the same time, environmentally-friendly production technologies and relevant legal instruments which oblige agricultural producers to protect the natural environment.

  8. Animation-based education as a gambling prevention tool: correcting erroneous cognitions and reducing the frequency of exceeding limits among slots players.

    Science.gov (United States)

    Wohl, Michael J A; Christie, Kelly-Lyn; Matheson, Kimberly; Anisman, Hymie

    2010-09-01

    In light of the financial harm that often accompanies problem gambling, and the difficulty in resolving it, there is a pressing need for prevention resources. In the present study, we examined the preventive effects of an animation-based video that educated participants on how slot machines function, the prudence of setting financial limits, and strategies to avoid problems. Non-problem gamblers (N = 242) at a slots venue were randomly assigned to watch either an animation or a control video. Compared to participants who watched the control video, those who watched the animation endorsed strategies to gamble within financial limits, reported greater behavioral intentions to use the strategies, and exceeded their pre-set limits less frequently during their subsequent gambling session. Some effects waned over a 30-day period suggesting booster sessions may be required for long term sustainability. The effectiveness of animation-based education as a prevention tool and the need for adjunctive measures is discussed.

  9. [Radioactivity of phosphorus implanted TiNi alloy].

    Science.gov (United States)

    Zhao, Xingke; Cai, Wei; Zhao, Liancheng

    2003-09-01

    Exposed to neutron flow, the phosphorus implanted TiNi alloy gets radioactive. This radioactive material is used in vascular stent for prevention and cure of restenosis. Phosphorus implantation is carried out in a plasma immerged ion implantation system, and the dose of phosphorus implantation is in the range of 2-10 x 10(17) cm-2. After ion implantation, the alloy is exposed to the slow neutron flow in a nuclear reactor, the dose of the slow neutron is 1.39-5.88 x 10(19) n/cm2. The radioactivity of the TiNi alloy was measured by liquid scintillation spectrometry and radio-chromic-film dosimetry. The result shows that whether the phosphorus is implanted or not, the TiNi alloy comes to be radioactive after exposure to neutron flow. Just after neutron irradiation, the radiation dose of phosphorus implanted TiNi alloy is about one hundred times higher than that of un-phosphorus implanted TiNi alloy. The radiation difference between phosphorus and un-phosphorus implanted alloy decreases as time elapses. Within three months after neutron irradiation, the average half-decay period of phosphorus implanted TiNi alloy is about 62 days. The radiation ray penetration of phosphorus implanted TiNi alloy is deeper than that of pure 32P; this is of benefit to making radiation uniformity between stent struts and reducing radiation grads beyond the edge of stent.

  10. Rhizosphere effect of different aquatic plants on phosphorus depletion

    Institute of Scientific and Technical Information of China (English)

    Zhenyu WANG; Shengfang WEN; Baoshan XING; Dongmei GAO; Fengmin LI

    2008-01-01

    A series of pot experiments with Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia and Phragmites communis were conducted to assess the phos-phorus depletion effect in the rhizosphere. The ratio of root to shoot, root morphology, phosphorus uptake efficiency and phosphorus utilization efficiency were analyzed. An obvious variation in phosphorus concentrations between the rhizosphere soil and non-rhizosphere soil was observed. The water-soluble P contents in the rhizosphere soil of A. philoxeroides, T. latifolia, S. sagittifolia and P. communis were reduced by 81%, 42%, 18% and 16%, respectively, compared with that in the non-rhizosphere soil. A. philox-eroides had the highest phosphorus uptake efficiency (1.32 mg/m), while T. latifolia achieved the effective phos-phorus depletion by the strong rooting system and the high phosphorus uptake efficiency (0.52 mg/m). T. latifolia not only used phosphorus to produce biomass economically, but also adjusted carbon allocation to the roots to explore the soil for more available phosphorus. A. philoxeroides and T. latifolia were more effective in depleting phosphorus in the rhizosphere than S. sagittifolia and P. communis.

  11. Derivation of a fuzzy national phosphorus export model using 84 Irish catchments

    International Nuclear Information System (INIS)

    Implementation of appropriate management strategies to mitigate diffuse phosphorus (P) pollution at the catchment scale is vitally important for the sustainable development of water resources in Ireland. An important element in the process of implementing such strategies is the prediction of their impacts on P concentrations in a catchment using a reliable mathematical model. In this study, a state-of-the-art adaptive neuro-fuzzy inference system (ANFIS) has been used to develop a new national P model capable of estimating average annual ortho-P concentrations at un-gauged catchments. Data from 84 catchments dominated by diffuse P pollution were used in developing and testing the model. Six different split-sample scenarios were used to partition the total number of the catchments into two sets, one to calibrate and the other to validate the model. The k-means clustering algorithm was used to partition the sets into clusters of catchments with similar features. Then for each scenario and for each cluster case, 11 different models, each of which consists of a linear regression sub-model for each cluster, were formulated by using different input variables selected from among six spatially distributed variables including phosphorus desorption index (PDI), runoff risk index (RRI), geology (GEO), groundwater (GW), land use (LU), and soil (SO). The success of the new approach over the conventional lumped, empirical, modelling approach was evident from the improved results obtained for most of the cases. In addition the results highlighted the importance of using information on PDI and RRI as explanatory input variables to simulate the average annual ortho-P concentrations. - Highlights: ► Develops a new national phosphorus export model for agricultural catchments in Ireland ► Improves on earlier empirical phosphorus export models by using k-means clustering method for partitioning data ► Uses ANFIS model to predict annual average ortho-phosphorus concentrations

  12. Derivation of a fuzzy national phosphorus export model using 84 Irish catchments

    Energy Technology Data Exchange (ETDEWEB)

    Nasr, Ahmed [School of Civil and Building Services Engineering, College Of Engineering and Built Environment, Dublin Institute of Technology, Bolton Street, Dublin 1 (Ireland); Bruen, Michael, E-mail: michael.bruen@ucd.ie [Centre for Water Resources Research, University College Dublin, Newstead Building, Richview, Belfield, Dublin 4 (Ireland)

    2013-01-15

    Implementation of appropriate management strategies to mitigate diffuse phosphorus (P) pollution at the catchment scale is vitally important for the sustainable development of water resources in Ireland. An important element in the process of implementing such strategies is the prediction of their impacts on P concentrations in a catchment using a reliable mathematical model. In this study, a state-of-the-art adaptive neuro-fuzzy inference system (ANFIS) has been used to develop a new national P model capable of estimating average annual ortho-P concentrations at un-gauged catchments. Data from 84 catchments dominated by diffuse P pollution were used in developing and testing the model. Six different split-sample scenarios were used to partition the total number of the catchments into two sets, one to calibrate and the other to validate the model. The k-means clustering algorithm was used to partition the sets into clusters of catchments with similar features. Then for each scenario and for each cluster case, 11 different models, each of which consists of a linear regression sub-model for each cluster, were formulated by using different input variables selected from among six spatially distributed variables including phosphorus desorption index (PDI), runoff risk index (RRI), geology (GEO), groundwater (GW), land use (LU), and soil (SO). The success of the new approach over the conventional lumped, empirical, modelling approach was evident from the improved results obtained for most of the cases. In addition the results highlighted the importance of using information on PDI and RRI as explanatory input variables to simulate the average annual ortho-P concentrations. - Highlights: ► Develops a new national phosphorus export model for agricultural catchments in Ireland ► Improves on earlier empirical phosphorus export models by using k-means clustering method for partitioning data ► Uses ANFIS model to predict annual average ortho-phosphorus concentrations

  13. Biosurfactants in agriculture

    OpenAIRE

    Sachdev, Dhara P.; Cameotra, Swaranjit S.

    2013-01-01

    Agricultural productivity to meet growing demands of human population is a matter of great concern for all countries. Use of green compounds to achieve the sustainable agriculture is the present necessity. This review highlights the enormous use of harsh surfactants in agricultural soil and agrochemical industries. Biosurfactants which are reported to be produced by bacteria, yeasts, and fungi can serve as green surfactants. Biosurfactants are considered to be less toxic and eco-friendly and ...

  14. Agricultural Development Bank Reform

    OpenAIRE

    Seibel, Hans Dieter

    2001-01-01

    Agricultural development banks (AgDBs), which are not viable, should either be closed, or transformed into self-reliant, sustainable financial intermediaries. Experience shows that reform is possible. Among the prominent cases are Bank Rakyat Indonesia (BRI) and Bank for Agriculture and Agricultural Cooperatives (BAAC, Thailand) as well as ADB/Nepal, which has been transforming its small farmer credit program into financially self-reliant local financial intermediaries owned and managed by th...

  15. Sustainable Agricultural Marketing Initiatives

    OpenAIRE

    Hakan Adanacıoğlu

    2015-01-01

    Sustainable marketing is a holistic approach that puts equal emphasis on environmental, social equity, and economic concerns in the development of marketing strategies. The purpose of the study is to examine and discuss the sustainable agricultural marketing initiatives practiced throughout the World and Turkey, and to put forth suggestions to further improve the performance of agricultural marketing initiatives in Turkey. Some of the sustainable agricultural marketing initiatives practiced a...

  16. Risk management in agriculture

    OpenAIRE

    Bharat Ramaswami; Shamika Ravi; S.D. Chopra

    2003-01-01

    This monograph was written to be part of the series of studies commissioned by the Ministry of Agriculture under the rubric of "State of Indian Farmer - A Millennium Study". On the basis of existing literature, this study documents the status of our knowledge on risks of agriculture and their management. Chapter 2 discusses the evidence on the nature, type and magnitude of agricultural risks. Chapter 3 discusses farmer strategies to combat risk. In addition to the mechanisms at the level of t...

  17. Agriculture for Development

    OpenAIRE

    World Bank

    2007-01-01

    The world's demand for food is expected to double within the next 50 years, while the natural resources that sustain agriculture will become increasingly scarce, degraded, and vulnerable to the effects of climate change. In many poor countries, agriculture accounts for at least 40 percent of GDP and 80 percent of employment. At the same time, about 70 percent of the world's poor live in rural areas and most depend on agriculture for their livelihoods. World Development Report 2008 seeks t...

  18. Changing urban phosphorus metabolism: Evidence from Longyan City, China.

    Science.gov (United States)

    Cui, Shenghui; Xu, Su; Huang, Wei; Bai, Xuemei; Huang, Yunfeng; Li, Guilin

    2015-12-01

    Rapid worldwide urbanization calls for a better understanding of phosphorus (P) metabolism and the interaction of the physical, ecological and social drivers of P cycling in urban systems. We quantified the P metabolism in Longyan, a city with a major agricultural economy, and analyzed its long-term trends over the rapid urbanization period of 1985-2010. Both input P (from 4811 t P to 14,296 t P) and output P (from 4565 t P to 13,509 t P) increased significantly. The agricultural subsystem contributed most to the P metabolism, accounting for 85% of total P input. The share of P input lost to the environment, i.e. discharge to water, accumulation in the soil and landfill, increased from 66% to 72%, while food production efficiency decreased from 48% to 29%. Per capita P input showed linear relationships with the Human Development Index (HDI), S-curve relationship with the urbanization rate, and logistic curve relationship with per capita disposable income. A more meat-based diet shift both in Longyan and surrounding cities greatly affected Longyan's food production structure. Our results demonstrate that P metabolic quantity, configuration, and efficiency in production systems can change drastically in response to changes in consumer and producer behavior as well as in socioeconomic structure. A larger regional scale should be considered in urban P management, when trying to mitigate the increase in P use. The results also imply that sustainable urban P management will require a system-wide, cross-sector and cross-boundary approach.

  19. The accuracy of soil map for variable rate phosphorus fertilisation

    Science.gov (United States)

    Maleki, M. R.; de Baerdemaeker, J.

    2009-04-01

    The basic concept of precision agriculture is to match the input and field requirement. The Variable rate (VR) fertilisation technique allows the ability to vary the rate of fertiliser application based on the field information, normally using field maps. In VR phosphorus fertilisation, field map is developed using grid soil sampling and soil P analysis. The objective of this study is to investigate how many samples are basically required to develop an accurate map. Fresh samples collected from 0.1 - 0.2 m depth of arable fields and grassland from three different fields and were subject to chemical analyses for soil P using two methods, Olsen P and extractable ammonium lactate P. The coordinates of each sample was located by a DGPS (Trimble® AgDGPS 132, USA) and converted into Lambert 72 coordinates to have the distance in the metric system. The result of each P analysis was put against its coordinates. Out of all sample records in each field (100 % of the data) 75, 50, 25 and 10% of the sample records were randomly selected and was used to develop field P map. The Surfer 8.00 (Golden Software) software was used to draw the maps using the Kriging method. Comparison of soil P maps showed a considerable difference while the number of samples used for map development is decreasing. However, there is a degree of similarity between maps using more soil samples. This means for developing an accurate map for precision agriculture it is not necessary to collect a massive sample sets.

  20. Induced mutation-facilitated genetic studies of seed phosphorus

    International Nuclear Information System (INIS)

    Both the chemical composition and total amount of seed phosphorus (P) are important to the end-use quality of cereal and legume seed crops, whether for use in human foods or animal feeds. They are also important to the management of P in agricultural production, and to the long-term sustainability of that production. About 75% (±10%) of seed total P is found as phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate). Mutations that block the synthesis or accumulation of phytic acid during seed development, often referred to as low phytic acid (lpa) mutations, have been isolated in maize (Zea mays L.), barley (Hordeum vulgare L.), rice (Oryza sativa L.), wheat (Triticum aestivum L.) and soybean (Glycine max L. (Merr.). Chromosomal mapping has identified as many as six non-allelic lpa loci in a single species (barley). Studies of lpa mutants has enhanced knowledge of the genes and proteins important to phytic acid P metabolism. While there has been substantial research into the biology of P uptake by plants, there has been little progress in the genetics of seed total P. Genetics that either decreases or increases seed total P might be of value for both enhancing the end-use quality of seed crops and for optimizing the utilization of P during agricultural production. As proof-of-principle, homozygosity for recessive alleles of barley lpa1 both blocks seed phytic acid accumulation by 50% and reduces seed total P by 15%, while having little impact on yield. The current status of lpa genetics and current efforts at isolating 'seed-total P' mutants, using both forward and reverse genetics approaches, will be described. (author)

  1. Induced Mutation-Facilitated Genetic Studies of Seed Phosphorus

    International Nuclear Information System (INIS)

    Both the chemical composition and total amount of seed phosphorus (P) are important to the end-use quality of cereal and legume seed crops, whether for use in human foods or animal feeds. They are also important to the management of P in agricultural production, and to the long-term sustainability of that production. About 75% (±10%) of seed total P is found as phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate). Mutations that block the synthesis or accumulation of phytic acid during seed development, often referred to as low phytic acid (lpa) mutations, have been isolated in maize (Zea mays L.), barley (Hordeum vulgare L.), rice (Oryza sativa L.), wheat (Triticum aestivum L.) and soybean (Glycine max L. (Merr.). Chromosomal mapping has identified as many as six non-allelic lpa loci in a single species (barley). Studies of lpa mutants has enhanced knowledge of the genes and proteins important to phytic acid P metabolism. While there has been substantial research into the biology of P uptake by plants, there has been little progress in the genetics of seed total P. Genetic factors that either decrease or increase seed total P might be of value for both enhancing the end-use quality of seed crops and for optimizing the utilization of P during agricultural production. As proof-of-principle, homozygosity for recessive alleles of barley lpa 1 both blocks seed phytic acid accumulation by 50% and reduces seed total P by 15%, while having little impact on yield. The current status of lpa genetics and current efforts at isolating 'seed-total P' mutants, using both forward and reverse genetics approaches, will be described. (author)

  2. Changing urban phosphorus metabolism: Evidence from Longyan City, China.

    Science.gov (United States)

    Cui, Shenghui; Xu, Su; Huang, Wei; Bai, Xuemei; Huang, Yunfeng; Li, Guilin

    2015-12-01

    Rapid worldwide urbanization calls for a better understanding of phosphorus (P) metabolism and the interaction of the physical, ecological and social drivers of P cycling in urban systems. We quantified the P metabolism in Longyan, a city with a major agricultural economy, and analyzed its long-term trends over the rapid urbanization period of 1985-2010. Both input P (from 4811 t P to 14,296 t P) and output P (from 4565 t P to 13,509 t P) increased significantly. The agricultural subsystem contributed most to the P metabolism, accounting for 85% of total P input. The share of P input lost to the environment, i.e. discharge to water, accumulation in the soil and landfill, increased from 66% to 72%, while food production efficiency decreased from 48% to 29%. Per capita P input showed linear relationships with the Human Development Index (HDI), S-curve relationship with the urbanization rate, and logistic curve relationship with per capita disposable income. A more meat-based diet shift both in Longyan and surrounding cities greatly affected Longyan's food production structure. Our results demonstrate that P metabolic quantity, configuration, and efficiency in production systems can change drastically in response to changes in consumer and producer behavior as well as in socioeconomic structure. A larger regional scale should be considered in urban P management, when trying to mitigate the increase in P use. The results also imply that sustainable urban P management will require a system-wide, cross-sector and cross-boundary approach. PMID:26142189

  3. Malawi - Conservation Agriculture

    Data.gov (United States)

    Millenium Challenge Corporation — The randomized control trial impact evaluation tests different strategies for communicating information about agricultural technologies to smallholder maize farmers...

  4. Regionalisation of Croatian Agriculture

    Directory of Open Access Journals (Sweden)

    Ferdo Bašić

    2007-03-01

    Full Text Available After becoming self-standing state one of new needs of Croatia important for agricultural profession, farmers, policy makers and public needs was regionalization of agriculture. It is the analyse of state of agroecological conditions in agrosphere and based on results identification and territorial separation of agricultural regions as parts of agrosphere with similar conditions for plant and animal growing and similar farming systems. On this track within a special project we fi nished an inventory of agrosphere, result of which is Regionalisation of Croatian Agriculture presented in this paper. Following wise message of old Chinese proverb cited above, the starting approach is the MFCAL concept (Multifunctional Character of Agriculture and Land, which means that apart from very important and primary economic, agriculture and agricultural land (soil in human life play other roles (functions of similar importance; environmental, social, cultural and spatial, as well as the role of shaping the cultural landscape as a factor of rural development. As well, we respect the point of view prevailing in EU that all natural resources used in agriculture but at the fi rst place soil as a major one, need sustainable use and efficient protection. Using the data on Land resource potential based primarily on data of General Soil Map of Croatia (GSM in a scale of 1:50 000 and results of our research in the period 2000 – 2003, the agrosphere of Croatia is divided in three agricultural regions; Pannonian with four, Mountain with two and Adriatic with three subregions.

  5. Agriculture and private sector

    DEFF Research Database (Denmark)

    Sahin, Sila; Prowse, Martin Philip; Weigh, Nadia

    Agriculture is and will continue to be critical to the futures of many developing countries. This may or may not be because agriculture can contribute directly and/or indirectly to economic growth. But it will certainly be critical because poverty is still predominantly a rural phenomenon...... and this looks set to remain for the next two decades at least. The agriculture and growth evidence paper series has been developed to cover a range of issues that are of most relevance to DFID staff. The paper is not intended to be a comprehensive overview of all issues relating to agriculture and the private...

  6. SYNTHESIS AND CHARACTERIZATION OF POLYBENZOXAZINE CONTAINING PHOSPHORUS

    Institute of Scientific and Technical Information of China (English)

    Ting-ting Zhang; Wei-wei Men; Ying Liu; Zai-jun Lu

    2012-01-01

    The novel benzoxazine monomer containing phosphorus has been synthesized based on multifunctional amine route from bis(4-aminophenyl)phenylphosphate,p-cresol and formaldehyde.Subsequently,the benzoxazine monomer was thermo-cured into polybenzoxazine containing phosphorus.The chemical structures were identified by nuclear magnetic resonance (NMR),Fourier transform infrared spectroscopy (FT-IR).The curing reaction was monitored by differential scanning calorimetry (DSC) and FT-IR.The thermal and flame-retardant properties of obtained polybenzoxazine were evaluated by dynamic mechanical thermal analysis (DMA),thermal gravimetric analysis (TGA) and oxygen index meter,respectively.The results show that the novel polybenzoxazine has high limiting oxygen index (38.1) and glass transition temperature (232℃).

  7. Peak phosphorus - peak food? The need to close the phosphorus cycle.

    Science.gov (United States)

    Rhodes, Christopher J

    2013-01-01

    The peak in the world production of phosphorus has been predicted to occur in 2033, based on world reserves of rock phosphate (URR) reckoned at around 24,000 million tonnes (Mt), with around 18,000 Mt remaining. This figure was reckoned-up to 71,000 Mt, by the USGS, in 2012, but a production maximum during the present century is still highly probable. There are complex issues over what the demand will be for phosphorus in the future, as measured against a rising population (from 7 billion to over 9 billion in 2050), and a greater per capita demand for fertiliser to grow more grain, in part to feed animals and meet a rising demand for meat by a human species that is not merely more populous but more affluent. As a counterweight to this, we may expect that greater efficiencies in the use of phosphorus - including recycling from farms and of human and animal waste - will reduce the per capita demand for phosphate rock. The unseen game changer is peak oil, since phosphate is mined and recovered using machinery powered by liquid fuels refined from crude oil. Hence, peak oil and peak phosphorus might appear as conjoined twins. There is no unequivocal case that we can afford to ignore the likelihood of a supply-demand gap for phosphorus occurring sometime this century, and it would be perilous to do so.

  8. Phosphorus reclamation through hydrothermal carbonization of animal manures.

    Science.gov (United States)

    Heilmann, Steven M; Molde, Joseph S; Timler, Jacobe G; Wood, Brandon M; Mikula, Anthony L; Vozhdayev, Georgiy V; Colosky, Edward C; Spokas, Kurt A; Valentas, Kenneth J

    2014-09-01

    Projected shortages of global phosphate have prompted investigation of methods that could be employed to capture and recycle phosphate, rather than continue to allow the resource to be essentially irreversibly lost through dilution in surface waters. Hydrothermal carbonization of animal manures from large farms was investigated as a scenario for the reclamation of phosphate for agricultural use and mitigation of the negative environmental impact of phosphate pollution. Hydrothermal reaction conditions were identified for poultry, swine, and cattle manures that resulted in hydrochar yields of 50-60% for all three manures, and >90% of the total phosphorus present in these systems was contained in the hydrochars as precipitated phosphate salts. Phosphate recovery was achieved in yields of 80-90% by subsequent acid treatment of the hydrochars, addition of base to acid extracts to achieve a pH of 9, and filtration of principally calcium phosphate. Phosphate recovery was achieved in yields of 81-87% based on starting manures by subsequent acid treatment of the hydrochars, addition of base to acid extracts to achieve a pH of 9, and filtration of principally calcium phosphate. Swine and cattle manures produced hydrochars with combustion energy contents comparable to those of high-end sub-bituminous coals. PMID:25111737

  9. Influence of nitrogen and phosphorus sources on mycorrhizal lettuces under organic farming

    Science.gov (United States)

    Scotti, Riccardo; Seguel, Alex; Cornejo, Pablo; Rao, Maria A.; Borie, Fernando

    2010-05-01

    Arbuscular mycorrhizal fungi (AMF) develop symbiotic associations with plants roots. These associations are very common in the natural environment and can provide a range of benefits to the host plant. AMF improve nutrition, enhance resistance to soil-borne pests and disease, increase resistance to drought and tolerance to heavy metals, and contribute to a better soil structure. However, agricultural intensive managements, such as the use of mineral fertilizes, pesticides, mouldboard tillage, monocultures and use of non-mycorrhizal crops, are detrimental to AMF. As a consequence, agroecosystems are impoverished in AMF and may not provide the full range of benefits to the crop. Organic farming systems may be less unfavourable to AMF because they exclude the use of water-soluble fertilisers and most pesticides, and generally they plan diverse crop rotations. The AMF develop the most common type of symbiosis in nature: about 90% of the plants are mycorrhizal and many agricultural crops are mycorrhizal. One of more mycorrhizal crops is lettuce, that is very widespread in intensive agricultural under greenhouse. Therefore, cultivated lettuce is know to be responsive to mycorrhizal colonization which can reach 80% of root length and contribute to phosphorus and nitrogen absorption by this plant specie. For this work four different lettuce cultivars (Romana, Milanesa, Grande Lagos and Escarola) were used to study mycorrhization under organic agricultural system, supplying compost from agricultural waste (1 kg m-2) as background fertilization for all plots, red guano as phosphorus source (75 U ha-1 and 150 U ha-1 of P2O5), lupine flour as nitrogen source (75 and 150 U/ha of N) and a combination of both. Lettuce plants were cultivated under greenhouse and after two months of growing, plants were harvested and dried and fresh weight of lettuce roots and shoots were evaluated. The number of spores, percentage of colonization, total mycelium and glomalin content were also

  10. Negative effects of excessive soil phosphorus on floristic quality in Ohio wetlands.

    Science.gov (United States)

    Stapanian, Martin A; Schumacher, William; Gara, Brian; Monteith, Steven E

    2016-05-01

    Excessive soil nutrients, often from agricultural runoff, have been shown to negatively impact some aspects of wetland plant communities. We measured plant-available phosphorus (Mehlich-3: MeP) in soil samples, and assessed the vascular plant community and habitat degradation at 27 emergent and 13 forested wetlands in Ohio, USA. We tested two hypotheses: (1) that an index of vegetation biological integrity based on floristic quality was lower in wetlands with higher concentrations of MeP in the soil, and (2) that higher concentrations of MeP occurred in wetlands with more habitat degradation (i.e., lower quality), as estimated by a rapid assessment method. Hypothesis (1) was supported for emergent, but not for forested wetlands. Hypothesis (2) was marginally supported (P=0.09) for emergent, but not supported for forested wetlands. The results indicate that the effect of concentration of phosphorus in wetland soils and the quality of plant species assemblages in wetlands is more complex than shown in site-specific studies and may depend in part on degree of disturbance in the surrounding watershed and dominant wetland vegetation type. Woody plants in forested wetlands are typically longer lived than herbaceous species in the understory and emergent wetlands, and may persist despite high inputs of phosphorus. Further, the forested wetlands were typically surrounded by a wide band of forest vegetation, which may provide a barrier against sedimentation and the associated phosphorus inputs to the wetland interior. Our results indicate that inferences about soil nutrient conditions made from rapid assessment methods for assessing wetland habitat condition may not be reliable. PMID:26896584

  11. Negative effects of excessive soil phosphorus on floristic quality in Ohio wetlands

    Science.gov (United States)

    Stapanian, Martin A.; Schumacher, William; Gara, Brian; Monteith, Steve

    2016-01-01

    Excessive soil nutrients, often from agricultural runoff, have been shown to negatively impact some aspects of wetland plant communities. We measured plant-available phosphorus (Mehlich-3: MeP) in soil samples, and assessed the vascular plant community and habitat degradation at 27 emergent and 13 forested wetlands in Ohio, USA. We tested two hypotheses: (1) that an index of vegetation biological integrity based on floristic quality was lower in wetlands with higher concentrations of MeP in the soil, and (2) that higher concentrations of MeP occurred in wetlands with more habitat degradation (i.e., lower quality), as estimated by a rapid assessment method. Hypothesis (1) was supported for emergent, but not for forested wetlands. Hypothesis (2) was marginally supported (P = 0.09) for emergent, but not supported for forested wetlands. The results indicate that the effect of concentration of phosphorus in wetland soils and the quality of plant species assemblages in wetlands is more complex than shown in site-specific studies and may depend in part on degree of disturbance in the surrounding watershed and dominant wetland vegetation type. Woody plants in forested wetlands are typically longer lived than herbaceous species in the understory and emergent wetlands, and may persist despite high inputs of phosphorus. Further, the forested wetlands were typically surrounded by a wide band of forest vegetation, which may provide a barrier against sedimentation and the associated phosphorus inputs to the wetland interior. Our results indicate that inferences about soil nutrient conditions made from rapid assessment methods for assessing wetland habitat condition may not be reliable.

  12. Effect of variety and level of phosphorus on the yield and yield components of lentil

    Directory of Open Access Journals (Sweden)

    S.K. Datta

    2013-06-01

    Full Text Available The experiment was carried out to study the effect of variety and level of phosphorus fertilizer on the yield and yield components of lentil at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during October 2009 to March 2010. Three lentil varieties viz. BINA masur 2, BINA masur 3 and BARI masur 4 and four levels of phosphorus viz. 0 kg P ha-1 (P0, 15 kg P ha-1 (P15, 30 kg P ha-1 (P30 and 45 kg P ha-1 (P45 were used in this experiment. Varieties showed significant influence on the all characters except plant height. The highest seed yield (1165 kg ha-1 was observed in BARI masur 4, and the lowest seed yield (1028 kg ha-1 was found in BINA masur 3. Phosphorus fertilizer had a significant effect on all the plant characters studied except 1000 seed weight. The highest seed yield (1222kg ha-1 was observed in P45 (45 kg P ha-1 treatment and the lowest seed yield (893 kg ha-1 was found in P0 treatment. In case of interaction, effect of cultivar and phosphorus fertilizer doses had a significant effect on all the plant characters studied except seeds pod -1 and 1000-seed weight. The highest seed yield (1317 kg ha-1 was obtained in V3 X P45 treatment, and the lowest seed yield (830 kg ha-1 was observed in V2 X P0 treatment combination. Among the varieties BINA masur 2 and BARI masur 4 were superior to BINA masur 3 in respect of yield performance with 30 kg P ha-1. BARI masur 4 fertilized with 30 kg P ha-1 produced the highest seed yield.

  13. Soil Phosphorus Gains and Losses with Afforestation: A Meta-analysis

    Science.gov (United States)

    McMahon, D.; Deng, Q.; Xiang, Y.; Yu, C. L.; Hui, D.; Jackson, R. B.

    2015-12-01

    Afforestation, the planting of trees on previously non-forested land, is commonly practiced around the world to provide wood, reduce erosion, and restore degraded agricultural land. Although afforestation has the potential to meet these objectives while increasing carbon uptake, its net impact on the soil depends on environmental conditions and land-use history. Availability of vital plant nutrients, such as phosphorus (P), may be altered by afforestation, but prior work has largely focused on soil carbon, and changes in soil P had not been quantitatively reviewed. We conducted a literature meta-analysis of changes in total and plant-available soil P with afforestation, compiling 49 studies representing 186 independent forest stands on five continents. Over the full dataset, mean concentration of plant-available phosphorus (mg kg-1 soil) increased by 22.7% with afforestation (bootstrapped 95% confidence interval = [15.1%, 30.7%]), while mean concentration of total phosphorus decreased by 13.5% (95% CI = [-18.4%, -8.6%]). These data reflect trends in upper mineral soil horizons, with sampling depths clustered around 20 cm and few studies reporting data below 50 cm. Differences in prior land use partially explain the substantial variation in effect size, with larger increases in available P and smaller decreases in total P when trees were planted on degraded soils. Trends in both available and total P were also enhanced with increasing time since afforestation, suggesting that changes in soil P concentrations are driven by cumulative processes rather than site preparation and planting. Our meta-analysis suggests that 1. afforestation can transform phosphorus into more plant-accessible forms, while potentially depleting total soil stocks of P, and 2. land-use history, more than climate or species planted, determines the effects of afforestation on soils' ability to meet the nutrient needs of vegetation.

  14. Factors Affecting Water Dynamics and Their Assessment in Agricultural Landscapes

    International Nuclear Information System (INIS)

    The intensification and extension of agriculture have contributed significantly to the global food production in the last five decades. However, intensification without due attention to the ecosystem services and sustainability of soil and water resources contributed to land and water quality degradation such as soil erosion, decreased soil fertility and quality, salinization and nutrient discharge to surface and ground waters. Land use change from forests to crop lands altered the vegetation pattern and hydrology of landscapes with increased nutrient discharge from crop lands to riverine environment. Global climate change will increase the amount of water required for agriculture in addition to water needed for further irrigation development causing water scarcity in many dry, arid and semi-arid regions. The water and nutrient use efficiencies of agricultural production systems are still below 40% in many regions across the globe. Nitrogen (N) and phosphorus (P) fertilizer use in agriculture have accelerated the cycling of these nutrients in the landscape and contributed to water quality degradation. Such nutrient pollution has a wide array of consequences including eutrophication of inland waters and marine ecosystems. While intensifying drought conditions, increasing water consumption and environmental pollution in many parts of the world threatens agricultural productivity and livelihood, these also provided opportunities for farmers to use improved land and water management technologies and practices to make agriculture resilient to external shocks

  15. Initial and residual effects of fertilizer phosphorus on soil phosphorus and maize yields on phosphorus fixing soils. A case study in south-west Kenya

    NARCIS (Netherlands)

    Eijk, van der D.; Janssen, B.H.; Oenema, O.

    2006-01-01

    The objective of this article is to provide experimental data and new insights about the best P fertilization strategy for phosphorus (P) fixing soils in the tropics. Two controversial strategies to manage soils with high phosphorus (P) fixation capacity were compared with regard to effects on maize

  16. Phosphorus removal and recovery from domestic wastewater in a novel process of enhanced biological phosphorus removal coupled with crystallization.

    Science.gov (United States)

    Zou, Haiming; Wang, Yan

    2016-07-01

    A new process of enhanced biological phosphorus removal coupled with crystallization recovery of phosphorus was developed here, where the feasibility of nutrients removal and potential for phosphorus recovery from domestic wastewater was further assessed. Results showed that an excellent nutrients removal and phosphorus recovery performance was achieved, in which the averaged COD, PO4(3-)-P and NO3(-)-N removal efficiencies were 82.6%, 87.5% and 91.6%, respectively and a total of 59.3% of phosphorus was recovered as hydroxyapatite. What's more, crystallization recovery of phosphorus greatly enhanced the biological phosphorus removal efficiency. After the incorporation of the phosphorus recovery column via side-stream, the phosphorus concentration of effluent was significantly decreased ranging from 1.24mg/L to 0.85mg/L, 0.52mg/L and 0.41mg/L at the lateral flow ratios of 0, 0.1, 0.2 and 0.3, respectively. The results obtained here would be beneficial to provide a prospective alternative for phosphorus removal and recovery from wastewater. PMID:27003794

  17. Distribution behavior of phosphorus in the coal-based reduction of high-phosphorus-content oolitic iron ore

    Institute of Scientific and Technical Information of China (English)

    Yong-sheng Sun; Yue-xin Han; Peng Gao; Duo-zhen Ren

    2014-01-01

    This study focuses on the reduction of phosphorus from high-phosphorus-content oolitic iron ore via coal-based reduction. The distribution behavior of phosphorus (i.e., the phosphorus content and the phosphorus distribution ratio in the metal, slag, and gas phases) during reduction was investigated in detail. Experimental results showed that the distribution behavior of phosphorus was strongly influenced by the reduction temperature, the reduction time, and the C/O molar ratio. A higher temperature and a longer reaction time were more favor-able for phosphorus reduction and enrichment in the metal phase. An increase in the C/O ratio improved phosphorus reduction but also hin-dered the mass transfer of the reduced phosphorus when the C/O ratio exceeded 2.0. According to scanning electron microscopy analysis, the iron ore was transformed from an integral structure to metal and slag fractions during the reduction process. Apatite in the ore was reduced to P, and the reduced P was mainly enriched in the metal phase. These results suggest that the proposed method may enable utilization of high-phosphorus-content oolitic iron ore resources.

  18. Biological phosphorus uptake under anoxic and aerobic conditions

    DEFF Research Database (Denmark)

    Kerrn-Jespersen, Jens Peter; Henze, Mogens

    1993-01-01

    Biological phosphorus removal was investigated under anoxic and aerobic conditions. Tests were made to establish whether phosphorus accumulating bacteria can take up phosphate under anoxic conditions and thus utilise nitrate as oxidant. Furthermore, it was tested how the amount of organic matter...... sludge from two different pilot plants incorporating phosphorus removal. The results showed that the phosphorus accumulating bacteria can be divided into two groups in respect of process; one group capable of utilising only oxygen as oxidant and another group capable of utilising both oxygen and nitrate...... taken up by the phosphorus accumulating bacteria during the anaerobic phase affects the total denitrification rate, as well as the rate at which the phosphorus accumulating bacteria take up phosphate under anoxic conditions. The tests were conducted as batch experiments in 21. reactors with activated...

  19. Determining phosphorus release rates to runoff from selected Alberta soils using laboratory rainfall simulation.

    Science.gov (United States)

    Wright, Charles R; Amrani, Mohamed; Akbar, Muhammad A; Heaney, Danial J; Vanderwel, Douwe S

    2006-01-01

    Phosphorus losses from agricultural land can cause accelerated eutrophication of surface water bodies. This study evaluated the use of soil test phosphorus (STP) levels to predict dissolved inorganic phosphorus (DIP) concentrations in runoff water from agricultural soils using laboratory rainfall simulation. The objectives of this study were to determine (i) to what extent STP concentrations can be used as a basis to predict P losses from Alberta soils and (ii) how extended rainfall simulation run times affected DIP losses. Soil samples collected from a total of 38 field sites, widely scattered throughout the southern half of Alberta, were subjected to rainfall simulation in the laboratory. The STP concentrations were determined using Miller-Axley, Norwest, Kelowna, Modified Kelowna Mehlich-III, and distilled water extraction methods. Each rainfall simulation event lasted for at least 90 min. Runoff samples were collected in time series for the duration of each simulation, during two distinct runoff intervals: (i) for the first 30 min of continuous runoff (T30) and (ii) for 40 min during runoff equilibrium (Teq). For all the STP extractants and both runoff intervals, the relationship with DIP-flow-weighted mean concentration (FWMC) was linear and highly significant with r2 values ranging from 0.74 to 0.96. However, the slopes of the resulting regression lines were, on average, 1.85 times greater for the T30 runoff interval over those computed for the Teq interval. Thus experimental methodology greatly influenced regression parameters, suggesting that more work was needed to verify these relationships under natural conditions. In addition, with many of the r2 values greater than 0.90 there would be little, if any, benefit derived by including soil properties in regression analysis.

  20. Both Phosphorus Fertilizers and Indigenous Bacteria Enhance Arsenic Release into Groundwater in Arsenic-Contaminated Aquifers.

    Science.gov (United States)

    Lin, Tzu-Yu; Wei, Chia-Cheng; Huang, Chi-Wei; Chang, Chun-Han; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

    2016-03-23

    Arsenic (As) is a human carcinogen, and arsenic contamination in groundwater is a worldwide public health concern. Arsenic-affected areas are found in many places but are reported mostly in agricultural farmlands, yet the interaction of fertilizers, microorganisms, and arsenic mobilization in arsenic-contaminated aquifers remains uncharacterized. This study investigates the effects of fertilizers and bacteria on the mobilization of arsenic in two arsenic-contaminated aquifers. We performed microcosm experiments using arsenic-contaminated sediments and amended with inorganic nitrogenous or phosphorus fertilizers for 1 and 4 months under aerobic and anaerobic conditions. The results show that microcosms amended with 100 mg/L phosphorus fertilizers (dipotassium phosphate), but not nitrogenous fertilizers (ammonium sulfate), significantly increase aqueous As(III) release in arsenic-contaminated sediments under anaerobic condition. We also show that concentrations of iron, manganese, potassium, sodium, calcium, and magnesium are increased in the aqueous phase and that the addition of dipotassium phosphate causes a further increase in aqueous iron, potassium, and sodium, suggesting that multiple metal elements may take part in the arsenic release process. Furthermore, microbial analysis indicates that the dominant microbial phylum is shifted from α-proteobacteria to β- and γ-proteobacteria when the As(III) is increased and phosphate is added in the aquifer. Our results provide evidence that both phosphorus fertilizers and microorganisms can mediate the release of arsenic to groundwater in arsenic-contaminated sediments under anaerobic condition. Our study suggests that agricultural activity such as the use of fertilizers and monitoring phosphate concentration in groundwater should be taken into consideration for the management of arsenic in groundwater.

  1. Lake Winnipeg Basin: Advocacy, challenges and progress for sustainable phosphorus and eutrophication control.

    Science.gov (United States)

    Ulrich, Andrea E; Malley, Diane F; Watts, Paul D

    2016-01-15

    Intensification of agricultural production worldwide has altered cycles of phosphorus (P) and water. In particular, loading of P on land in fertilizer applications is a global water quality concern. The Lake Winnipeg Basin (LWB) is a major agricultural area displaying extreme eutrophication. We examined the eutrophication problem in the context of the reemerging global concern about future accessibility of phosphate rock for fertilizer production and sustainable phosphorus management. An exploratory action research participatory design was applied to study options for proactivity within the LWB. The multiple methods, including stakeholder interviews and surveys, demonstrate emerging synergies between the goals of reversing eutrophication and promoting food security. Furthermore, shifting the prevalent pollutant-driven eutrophication management paradigm in the basin toward a systemic, holistic and ecocentric approach, integrating global resource challenges, requires a mutual learning process among stakeholders in the basin to act on and adapt to ecosystem vulnerabilities. It is suggested to continue aspects of this research in a transdisciplinary format, i.e., science with society, in response to globally-expanding needs and concerns, with a possible focus on enhanced engagement of indigenous peoples and elders.

  2. Lake Winnipeg Basin: Advocacy, challenges and progress for sustainable phosphorus and eutrophication control.

    Science.gov (United States)

    Ulrich, Andrea E; Malley, Diane F; Watts, Paul D

    2016-01-15

    Intensification of agricultural production worldwide has altered cycles of phosphorus (P) and water. In particular, loading of P on land in fertilizer applications is a global water quality concern. The Lake Winnipeg Basin (LWB) is a major agricultural area displaying extreme eutrophication. We examined the eutrophication problem in the context of the reemerging global concern about future accessibility of phosphate rock for fertilizer production and sustainable phosphorus management. An exploratory action research participatory design was applied to study options for proactivity within the LWB. The multiple methods, including stakeholder interviews and surveys, demonstrate emerging synergies between the goals of reversing eutrophication and promoting food security. Furthermore, shifting the prevalent pollutant-driven eutrophication management paradigm in the basin toward a systemic, holistic and ecocentric approach, integrating global resource challenges, requires a mutual learning process among stakeholders in the basin to act on and adapt to ecosystem vulnerabilities. It is suggested to continue aspects of this research in a transdisciplinary format, i.e., science with society, in response to globally-expanding needs and concerns, with a possible focus on enhanced engagement of indigenous peoples and elders. PMID:26475238

  3. Water and nutrient budgets of ponds in integrated agriculture-aquaculture systems in the Mekong Delta, Vietnam.

    NARCIS (Netherlands)

    Nhan, D.K.; Verdegem, M.C.J.; Milstein, A.; Verreth, J.A.J.

    2008-01-01

    A participatory on-farm study analysed water and nutrient budgets of six low and four high water-exchange ponds of integrated agriculture-aquaculture (IAA) farms in the Mekong delta. Water, nitrogen (N), organic carbon (OC) and phosphorus (P) flows through the ponds were monitored, and data on fish

  4. Conservation Agriculture in Europe

    Directory of Open Access Journals (Sweden)

    Á. Kertész

    2014-03-01

    Yield performance and stability, operating costs, environmental policies and programs of the Common Agricultural Policy (CAP, and climate change will likely be the major driving forces defining the direction and for the extension of CA in Europe. The role of agriculture in climate change mitigation in the EU is discussed in the paper.

  5. Legislature Abolishes Agricultural Tax

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

      China's 2,600-year-old agricultural tax will be rescinded as of Jan. 1,2006, after China's top legislature voted on December 27 to adopt a motion on the regulations revoking the agricultural tax.……

  6. Agricultural Industrialization: It's Inevitable

    OpenAIRE

    Urban, Thomas N.

    1991-01-01

    The industrialization of agriculture is with us. It's driven by consumer and processor needs, supported by new and useful technology, and augmented by the severe agricultural recession of the 1980s, which changed attitudes towards risk. The consequences for farm policy and rural development are significant, and should be favorable.

  7. Managing risk in agriculture

    OpenAIRE

    2015-01-01

    "This book examines the implications of risk management for policy in agriculture. Opening with a chapter on risk management principles and guidelines for policy design in agriculture, the book goes on to look at quantitative analysis of risk and then at policy in various countries." --> Publisher's description.

  8. Agriculture and food processing

    International Nuclear Information System (INIS)

    This chapter discuss the application of nuclear technology in agriculture sector. Nuclear Technology has help agriculture and food processing to develop tremendously. Two techniques widely use in both clusters are ionization radiation and radioisotopes. Among techniques for ionizing radiation are plant mutation breeding, SIT and food preservation. Meanwhile radioisotopes use as a tracer for animal research, plant soil relations water sedimentology

  9. Agriculture. Pt. 1

    International Nuclear Information System (INIS)

    The study investigates the impact of agriculture on the earth's atmosphere. It describes the natural carbon cycle, the socioeconomic factors that influence it, and the climate effects. The climatic relevance of gaseous sulphur and nitrogen compounds, methane and other hydrocarbons, and ammonia emissions from biological and agricultural process is discussed. (SR)

  10. Good Wetland Agricultural Practices

    NARCIS (Netherlands)

    Hengsdijk, H.; Zingstra, H.L.

    2009-01-01

    Within the Guiding Agriculture Wetland Interaction (GAWI) project the Driver!Pressure!State! Impact!Response (DPSIR) approach has been adopted to describe and analyse agriculture!wetland interactions. The DPSIR approach provides a consistent framework to analyse the complex causal chain among driver

  11. Agricultural Sector Risk Assessment

    OpenAIRE

    World Bank

    2016-01-01

    In the agricultural sector, risks are inherent and ubiquitous, posing potentially serious consequences for stakeholders and consumers. Risks disrupt supply chains, causing extensive financial and economic losses. Agricultural risks are also the principal cause of transient food insecurity, creating a poverty trap for millions of households across the developing world that enforces a viciou...

  12. Metabolism of nonparticulate phosphorus in an acid bog lake

    Energy Technology Data Exchange (ETDEWEB)

    Koenings, J. P.

    1977-01-01

    In North Gate Lake, an acid bog lake located on the northern Michigan-Wisconsin border, U.S.A., the algal nutrient inorganic phosphate (FRP) is not detectable by chemical means. Organic phosphorus (FUP) represents 100% of the detectable filterable phosphorus. The availability and cycling of this organic fraction are of considerable interest in regard to the primary productivity of this system. To clarify these relationships, the cycling of nonparticulate forms of phosphorus found in the epilimnion of this lake was studied.

  13. The Modern Phosphorus Sustainability Movement: A Profiling Experiment

    OpenAIRE

    Andrea E. Ulrich; Ewald Schnug

    2013-01-01

    Since the “peak phosphorus†concept emerged in 2007, concerns about the future availability of phosphate rock have funneled into a growing number of actions, often in the form of new and innovative platforms focusing on phosphorus sustainability. This trend seems to continue on different levels and in different formats, which makes the landscape of activities increasingly blurred and complex. This article considers the emerging phase of the modern phosphorus sustainability movement. It pro...

  14. Isotopic fingerprint for phosphorus in drinking water supplies

    OpenAIRE

    Gooddy, Daren C.; Lapworth, Dan J.; Ascott, Matthew J.; Sarah A Bennett; Heaton, Timothy H.E.; Surridge, Ben W.J.

    2015-01-01

    Phosphate dosing of drinking water supplies, coupled with leakage from distribution networks, represents a significant input of phosphorus to the environment. The oxygen isotope composition of phosphate (δ18OPO4), a novel stable isotope tracer for phosphorus, offers new opportunities to understand the importance of phosphorus derived from sources such as drinking water. We report the first assessment of δ18OPO4 within drinking water supplies. A total of 40 samples from phosphate-dosed distrib...

  15. Eutrophication of aquatic ecosystems: Bistability and soil phosphorus

    OpenAIRE

    Stephen R Carpenter

    2005-01-01

    Eutrophication (the overenrichment of aquatic ecosystems with nutrients leading to algal blooms and anoxic events) is a persistent condition of surface waters and a widespread environmental problem. Some lakes have recovered after sources of nutrients were reduced. In others, recycling of phosphorus from sediments enriched by years of high nutrient inputs causes lakes to remain eutrophic even after external inputs of phosphorus are decreased. Slow flux of phosphorus from overfertilized soils ...

  16. Metabolism of nonparticulate phosphorus in an acid bog lake

    International Nuclear Information System (INIS)

    In North Gate Lake, an acid bog lake located on the northern Michigan-Wisconsin border, U.S.A., the algal nutrient inorganic phosphate (FRP) is not detectable by chemical means. Organic phosphorus (FUP) represents 100% of the detectable filterable phosphorus. The availability and cycling of this organic fraction are of considerable interest in regard to the primary productivity of this system. To clarify these relationships, the cycling of nonparticulate forms of phosphorus found in the epilimnion of this lake was studied

  17. Phosphorus speciation in sediments of Lake Hongfeng, China

    Institute of Scientific and Technical Information of China (English)

    JIANG Cuihong; HU Jiwei; HUANG Xianfei; LI Cunxiong; DENG Jiajun; ZHANG Jie; LIU Feng

    2011-01-01

    This study was conducted to evaluate the distribution characteristics of phosphorus and its species in 14 sediments samples collected from Lake Hongfeng based on sequential extraction. Lake Hongfeng, a major drinking-water source for Guiyang City in southwestern China, is one of the largest artificial reservoirs located in a typical karstic area of the Yunnan-Guizhou Plateau. The results of this study indicate that the average percentages of DP, Al-P, Fe-P, Ca-P and OP in the lake sediments were 0.52, 6.59, 6.09, 42.85 and 40.27, respectively. The concentrations of organic phosphorus (OP) were lower than those of inorganic phosphorus (IP), which consisted mainly of calcium-bound phosphorus (Ca-P). The high concentrations of Ca-P may temporarily control the release of phosphorus from the sediments because it is a relatively stable, inert, and non-bioavailable phosphorus fraction. However, a large number of phosphate solubilizing bacteria can transform insoluble phosphate into bioavailable forms. Moreover, the concentrations of total phosphorus (TP) in the lake sediments were high; thus, the potential for the release of phosphorus from the sediments to the water column and phosphorus bioavailability were still significant. Further statistical analyses of the results revealed significant correlations between phosphorus species in sediments from the lake with two extractable principal component species (PCs) and five selectable cluster levels allowing interpretation of possible origins of phosphorus loading and the release of phosphorus. Furthermore, available remediation measures were briefly assessed for the lake with consideration of its distinctive environmental features.

  18. Importance of Farm Phosphorus Mass Balance and Management Options

    OpenAIRE

    Maguire, Rory

    2014-01-01

    Phosphorus is a naturally occurring element that is one of 16 elements essential for plant growth and animal health. Research has documented that applying phosphorus in fertilizers or manure increases crop growth and yield on soils that are below critical agronomic levels, as measured during routine soil testing. Although the economic benefits of phosphorus fertilization on crop production are well-documented, too much of a good thing can be detrimental to the environment. Excessive soil phos...

  19. Agriculture biotechnology report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This report provides the basis for an overall agriculture biotechnology strategy for Saskatchewan, encompassing all aspects of the biotechnology sector and supporting institutions. It presents results of a survey of over 70 industry and public sector leaders in agriculture biotechnology in order to assist Saskatchewan Agriculture & Food in defining its role and involvement in the agriculture biotechnology industry. Issues examined include: Goals for the agriculture biotechnology industry; research and development; technology transfer and commercialisation; infrastructure and services; human resources; legislation and policy; funding; future core areas of research and development; and the role of government in developing the industry. The report concludes with lists of recommendations. The supplement lists the survey questions and responses.

  20. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J. [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H.; Morita, Y.; Ohshima, T.

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  1. Sustainable Agricultural Marketing Initiatives

    Directory of Open Access Journals (Sweden)

    Hakan Adanacıoğlu

    2015-07-01

    Full Text Available Sustainable marketing is a holistic approach that puts equal emphasis on environmental, social equity, and economic concerns in the development of marketing strategies. The purpose of the study is to examine and discuss the sustainable agricultural marketing initiatives practiced throughout the World and Turkey, and to put forth suggestions to further improve the performance of agricultural marketing initiatives in Turkey. Some of the sustainable agricultural marketing initiatives practiced around the world are carried out through civil organizations. Furthermore; some of these initiatives have also launched by farmers, consumers, food processors and retailers. The long-term strategies to increase these initiatives should be determined due to the fact that examples of successful sustainable agricultural marketing initiatives are inadequate and cannot be spread in Turkey. In this context, first of all, the supports provided by the government to improve agricultural marketing systems, such as EU funds for rural development should be compatible with the goals of sustainable marketing. For this purpose, it should be examined whether all proposed projects related to agricultural marketing meet the social, economic, and environmental principles of sustainable marketing. It is important that supporting organizations, especially civil society organisations, should take an active role for faster dissemination and adoption of sustainable agricultural marketing practices in Turkey. These organizations may provide technical assistance in preparing successful project proposals and training to farm groups. In addition, the other organizations, such as local administrations, producers' associations, cooperatives, can contribute to the success of sustainable agricultural marketing initiatives. The use of direct marketing strategies and vertical integration attempts in sustainable agricultural marketing initiatives that will likely be implemented in Turkey is

  2. Phosphorus limitation in biofiltration for drinking water treatment

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Bacterial growth potential(BGP) method and two parallel pilot-scale biofilters were used to investigate phosphorus limitation and itseffect on the removal of organic matters in biofiltration for drinking water treatment. Addition of phosphorus can substantially increase the BGPsof the samples. Its effect was equivalent to that of addition of a mixture of various inorganic nutrients including phosphorus. The biofilter withphosphate added into its influent performed a higher biological stability of the effluent and a higher CODMn removal than the control filter. Theseresults suggested that phosphorus was the limiting nutrient in the biofiltration and the removal efficiency of organic matters could be improved byadding phosphate into the influent.

  3. Role of extracellular exopolymers on biological phosphorus removal

    Institute of Scientific and Technical Information of China (English)

    LIU Ya-nan; XUE Gang; YU Shui-li; ZHAO Fang-bo

    2006-01-01

    Three sequencing batch reactors supplied with different carbon sources were investigated. The system supplied with glucose gained the best enhanced biological phosphorus removal although all of the three reactors were seeded from the same sludge. With the measurement of poly-β-hydroxyalkanoate (PHA) concentration, phosphorus content in sludge and extracellular exopolymers (EPS) with scanning electron microscopy (SEM) combined with energy dispersive spectrometry (EDS), it was found that the biosorption effect of EPS played an important role in phosphorus removal and that the amount of PHA at the end of anaerobic phase was not the only key factor to determine the following phosphorus removal efficiency.

  4. Phosphorus removal from domestic wastewater by Echinodorus cordifolius L.

    Science.gov (United States)

    Torit, Jirawan; Siangdung, Wipawan; Thiravetyan, Paitip

    2012-01-01

    This study was to use the plants to remove phosphorus from domestic wastewater which contained high phosphorus concentration. Six higher plant species such as Crinum asiaticum L., Echinodorus cordifolius L., Spathiphyllum clevelandii Schott, Rhizophora apiculata Blume, Thalia dealbata J.fraser., Heliconia psittacorum L.f. were screened for phosphorus removal. Plants were grown in the domestic wastewater and the remaining phosphorus-phosphate concentration in the systems was determined. The results indicated that among studied plants, Echinodorus cordifolius L. was the best for phosphorus removal. Using this plant will improve the quality of domestic wastewater which contained excess phosphorus concentration and induced eutrophication. The relationship between the plants, microorganisms, and soil in the system were also investigated. In this system, adsorption by soil was the major role for phosphorus removal (71%), followed by E. cordifolius (16%), microorganisms in domestic wastewater (7%), and microorganisms in soil (6%). These results indicated the ability of E. cordifolius to remove phosphorus which was superior to that of the microorganisms in the system. Moreover, the rapid phosphorus removal was concomitant to the growth, photosynthesis activity and biomass of E. cordifolius grown in domestic wastewater. The C:N:P ratio of E. cordifolius tissue in the system indicated that elements were taken up from the wastewater. From these results, the suitability of E. cordifolius for domestic wastewater treatment was confirmed.

  5. Phosphorus removal from domestic wastewater by Echinodorus cordifolius L.

    Science.gov (United States)

    Torit, Jirawan; Siangdung, Wipawan; Thiravetyan, Paitip

    2012-01-01

    This study was to use the plants to remove phosphorus from domestic wastewater which contained high phosphorus concentration. Six higher plant species such as Crinum asiaticum L., Echinodorus cordifolius L., Spathiphyllum clevelandii Schott, Rhizophora apiculata Blume, Thalia dealbata J.fraser., Heliconia psittacorum L.f. were screened for phosphorus removal. Plants were grown in the domestic wastewater and the remaining phosphorus-phosphate concentration in the systems was determined. The results indicated that among studied plants, Echinodorus cordifolius L. was the best for phosphorus removal. Using this plant will improve the quality of domestic wastewater which contained excess phosphorus concentration and induced eutrophication. The relationship between the plants, microorganisms, and soil in the system were also investigated. In this system, adsorption by soil was the major role for phosphorus removal (71%), followed by E. cordifolius (16%), microorganisms in domestic wastewater (7%), and microorganisms in soil (6%). These results indicated the ability of E. cordifolius to remove phosphorus which was superior to that of the microorganisms in the system. Moreover, the rapid phosphorus removal was concomitant to the growth, photosynthesis activity and biomass of E. cordifolius grown in domestic wastewater. The C:N:P ratio of E. cordifolius tissue in the system indicated that elements were taken up from the wastewater. From these results, the suitability of E. cordifolius for domestic wastewater treatment was confirmed. PMID:22416873

  6. Determination of phosphorus in hypereutectic aluminium-silicon alloys.

    Science.gov (United States)

    Mukai, K

    1972-04-01

    A reproducible method is described for determination of small amounts of phosphorus (from 0.0005% to 0.02%) in hypereutectic aluminium-silicon complex alloys. The method permits the separate determination of phosphorus in acid-soluble and acid-insoluble fractions. Phosphomolybdate is extracted with n-butanol-chloroform solvent mixture and back-extracted with a btannous chloride reducing solution. The phosphorus content of a sample cut into small pieces decreases during storage; loss of phosphorus is negligible on acid dissolution under oxidizing conditions. PMID:18961077

  7. A novel approach for phosphorus recovery and no wasted sludge in enhanced biological phosphorus removal process with external COD addition.

    Science.gov (United States)

    Xia, Cheng-Wang; Ma, Yun-Jie; Zhang, Fang; Lu, Yong-Ze; Zeng, Raymond J

    2014-01-01

    In enhanced biological phosphorus removal (EBPR) process, phosphorus (P) in wastewater is removed via wasted sludge without actual recovery. A novel approach to realize phosphorus recovery with special external chemical oxygen demand (COD) addition in EBPR process was proposed. During the new operating approach period, it was found that (1) no phosphorus was detected in the effluent; (2) with an external addition of 10 % of influent COD amount, 79 % phosphorus in the wastewater influent was recovered; (3) without wasted sludge, the MLVSS concentration in the system increased from 2,010 to 3,400 mg/L and kept stable after day 11 during 24-day operating period. This demonstrates that the novel approach is feasible to realize phosphorus recovery with no wasted sludge discharge in EBPR process. Furthermore, this approach decouples P removal and sludge age, which may enhance the application of membrane bioreactor for P removal. PMID:24122666

  8. Quantitative aspects of phosphorus absorption and excretion in horses

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, Ives Claudio da Silva; Abdalla, Adibe Luiz; Vitti, Dorinha Miriam Silber Schmidt [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Nutricao Animal]. E-mails: icsbueno@cena.usp.br; abdalla@cena.usp.br; dovitti@cena.usp.br; Furtado, Carlos Eduardo [Universidade Estadual de Maringa, PR (Brazil). Dept. de Zootecnia]. E-mail: cefurtado@uem.br

    2007-07-01

    Phosphorus (P) is one of the most polluting nutrients because of high husbandry concentrations in restricted areas. The present study compiles data from previous studies dealing with true digestibility of different P levels in diets for horses. Database consisted of results from two experiments carried out at the Centre for Nuclear Energy in Agriculture (CENA/USP), using horses fed different levels of P (n=28). True absorption of phosphorus was determined by isotopic dilution technique, using {sup 32}P as tracer. All parameters (P{sub ING}: ingested P; P{sub ABS}: absorbed P; P{sub FECTOT}: total faecal P excretion; P{sub FECENDO}: endogenous faecal P; P{sub URI}: total urinary excretion; and P{sub RET}: retained P) were normalized according to body weight (BW) and linear and quadratic regressions between P{sub ING} and the other parameters were tested. No quadratic effect was observed. P{sub ING} ranged from 41 to 264 mg/kg BW. Faecal P excretion was affected by intake, analysing by total (P{sub FECTOT} = 0.888 (S.E. 0.058) P{sub ING} - 29.40 (S.E. 8.14) (P<0.0001; RMSE=20.37; R{sup 2}=0.90) or by endogenous fraction (P{sub FECENDO} = 0.095 (S.E. 0.029) P{sub ING} + 12.10 (S.E. 4.16) (P=0.0034; RMSE=10.41; {sup R}2=0.29). Urinary P excretion was not affected by intake (P=0.35), although ranging from 0.06 to 59.20 mg/kg BW. The same occurred for P{sub RET} (P=0.25) ranging from -13.69 to 88.78 mg/kg BW. P absorption also was affect by P intake (P{sub ABS} = 0.195 (S.E. 0.060) P{sub ING} + 42.19 (S.E. 8.45) (P=0.0031; RMSE=21.15; R{sup 2}=0.29). The present study showed that only a small part of ingested P was absorbed, i.e. most of ingested P was excreted via faeces, contributing for environmental pollution. (author)

  9. Phosphorus geochemical cycling inferences from high frequency lake monitoring

    Science.gov (United States)

    Crockford, Lucy; Jordan, Philip; Taylor, David

    2013-04-01

    Freshwater bodies in Europe are required to return to good water quality status under the Water Framework Directive by 2015. A small inter-drumlin lake in the northeast of Ireland has been susceptible to eutrophic episodes and the presence of algal blooms during summer since annual monitoring began in 2002. While agricultural practice has been controlled by the implementation of the Nitrates Directive in 2006, the lake is failing to recover to good water quality status to meet with the Water Framework Directive objectives. Freshwaters in Ireland are regarded, in the main, as phosphorus (P) limited so identifying the sources of P possibly fuelling the algal blooms may provide an insight into how to improve water quality conditions. In a lake, these sources are divided between external catchment driven loads, as a result of farming and point sources, and P released from sediments made available to photic waters through internal lake mechanisms. High frequency sensors on data-sondes, installed on the lake in three locations, have provided chlorophyll a, redox potential, dissolved oxygen, temperature, pH, conductivity and turbidity data since March 2010. A data-sonde was installed in the hypolimnion to observe the change in lake conditions as P is released from lake sediments as a result of geochemical cycling with iron during anoxic periods. As compact high frequency sampling equipment for P analysis is still in its infancy for freshwaters, a proxy measurement of geochemical cycling in lakes would be useful to determine fully the extent of P contribution from sediments to the overall P load. Phosphorus was analysed once per month along with a number of other parameters and initial analysis of the high frequency data has shown changes in readings when known P release from lake sediments has occurred. Importantly, these data have shown when these P enriched hypolimnetic waters may be re-introduced to shallower waters in the photic zone, by changes in dissolved oxygen

  10. Effect of phytase supplementation on apparent phosphorus digestibility and phosphorus output in broiler chicks fed low-phosphorus diets

    Directory of Open Access Journals (Sweden)

    Xian-Ren Jiang

    2015-04-01

    Full Text Available This study was conducted to evaluate the effect of supplemental phytase in broiler chicks fed different low levels of total phosphorus (P on the apparent phosphorus digestibility (APD and phosphorus output (PO in the faeces and ileal digesta. After fed a standard broiler starter diet from day 0 to 14 post-hatch, a total of 144 male broiler chicks were allocated to 6 groups for a 7-d experiment with a 2 × 3 factorial design comparing phytase (supplemented without (CTR or with 400 FTU/kg phytase (PHY and total P levels (2.0, 2.5 and 3.0 g/kg. The faecal samples were collected from day 17 to 21 post-hatch. At 22 days of age, all the chicks were slaughtered and collected the ileal digesta. Phytase supplementation significantly (P < 0.01 increased APD and decreased PO in the faeces and ileal digesta in comparison with the CTR group. In addition, PO in the faeces expressed as g/kg DM diets and faeces (Diet × P level, P = 0.047 and < 0.01, respectively as well as PO in the ileal digesta expressed as g/kg DM digesta (Diet × P level, P = 0.04 were affected by diet and P level, which were due to the significant reduction (P < 0.01 by PHY supplementation to the diets with 3.0 g/kg total P. The results evidenced that supplemental phytase improved the APD and PO when chicks was fed 3.0 g/kg total P diet, while lower total P levels may limit exogenous phytase efficacy.

  11. BOOK REVIEWS - Precision agriculture

    Directory of Open Access Journals (Sweden)

    Stanisław Samborski

    2007-01-01

    Full Text Available Precision agriculture (PA is a term, which has recently become very popular in agronomy. In short this term means crop production based on site-specific crop management (SSCM. Precision agriculture is an integrated agricultural management system incorporating different science disciplines e.g. crop science, agricultural engineering and geostatistics. It also uses numerous tools i.e., geographic information system (GIS, Global Positioning System (GPS, remote sensing yield monitors. Because of the multidisciplinary character of precision agriculture, books published on this subject differ in their content. The first books on this topic appeared in the mid 90’ of the last century. The intention of this paper is to present reviews of three books the titles of which each contains the term “precision agriculture”. The books are as follows:1 Handbook of Precision Agriculture – Principles and Applications (2006 edited by Ancha Srinivasan. 2 Precision Agriculture’05 (2005 edited by John V. Stafford 3 Precision Agriculture (2006 by Terry A. Brasse.

  12. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  13. Numerical Simulation of Phosphorus Removal from Silicon by Induction Vacuum Refining

    Science.gov (United States)

    Zheng, Songsheng; Engh, Thorvald Abel; Tangstad, Merete; Luo, Xue-Tao

    2011-08-01

    Phosphorus can be expected to evaporate preferentially from silicon melt by induction vacuum refining (IVR). In the present study, on the assumption of phosphorus evaporating from silicon melt as gas species P and P 2, a numerical model of phosphorus removal from silicon by IVR was developed. The factors affecting phosphorus removal in decreasing order are temperature, chamber pressure, geometry of silicon melt, holding time, and original phosphorus concentration. Calculated phosphorus removal shows good agreement with the present experimental data.

  14. Patient education for phosphorus management in chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Kalantar-Zadeh K

    2013-05-01

    Full Text Available Kamyar Kalantar-ZadehHarold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California Irvine’s School of Medicine, Irvine, CA, USAObjectives: This review explores the challenges and solutions in educating patients with chronic kidney disease (CKD to lower serum phosphorus while avoiding protein insufficiency and hypercalcemia.Methods: A literature search including terms “hyperphosphatemia,” “patient education,” “food fatigue,” “hypercalcemia,” and “phosphorus–protein ratio” was undertaken using PubMed.Results: Hyperphosphatemia is a strong predictor of mortality in advanced CKD and is remediated via diet, phosphorus binders, and dialysis. Dietary counseling should encourage the consumption of foods with the least amount of inorganic or absorbable phosphorus, low phosphorus-to-protein ratios, and adequate protein content, and discourage excessive calcium intake in high-risk patients. Emerging educational initiatives include food labeling using a “traffic light” scheme, motivational interviewing techniques, and the Phosphate Education Program – whereby patients no longer have to memorize the phosphorus content of each individual food component, but only a “phosphorus unit” value for a limited number of food groups. Phosphorus binders are associated with a clear survival advantage in CKD patients, overcome the limitations associated with dietary phosphorus restriction, and permit a more flexible approach to achieving normalization of phosphorus levels.Conclusion: Patient education on phosphorus and calcium management can improve concordance and adherence and empower patients to collaborate actively for optimal control of mineral metabolism.Keywords: hyperphosphatemia, renal diet, phosphorus binders, educational programs, food fatigue, concordance

  15. Digestible phosphorus levels for barrows from 50 to 80 kg

    Directory of Open Access Journals (Sweden)

    Viviane Maria Oliveira dos Santos Nieto

    2016-05-01

    Full Text Available ABSTRACT This study was carried out to evaluate the levels of digestible phosphorus in diets for barrows with a high potential for lean meat deposition from 50 to 80 kg. Eighty barrows, with an initial weight of 47.93±3.43 kg, were distributed in completely randomized blocks, with each group given five levels of digestible phosphorus (1.86, 2.23, 2.61, 2.99, and 3.36 g kg−1. There were eight replicates, and two animals per experimental unit. Phosphorus levels did not significantly influence feed intake, weight gain, or feed conversion ratio. Daily digestible phosphorus intake increased linearly as levels of phosphorus in the diet were increased. Phosphorus levels did not significantly influence muscle depth, loin eye area, backfat thickness, or the percentage and quantity of lean meat in the carcass. A linear increase was observed for feeding cost as the levels of digestible phosphorus in the diet were increased, and the level of 1.86 g kg−1 cost 29.4% less when compared with the level of 2.61 g kg−1. The dry matter, natural matter, the coefficient of the residue, and volatile solids of the waste were not significantly influenced by phosphorus levels. Conversely, it was possible to observe an increasing linear effect for total solids, total phosphorus, and total nitrogen in the waste of animals receiving diets with increased levels of digestible phosphorus. The level of 1.86 g kg−1, which corresponded to a daily intake of 4.77 g−1 of digestible phosphorus, meets the requirements of barrows weighing 50 to 80 kg.

  16. Calcium effect on the metabolic pathway of phosphorus accumulating organisms in enhanced biological phosphorus removal systems.

    Science.gov (United States)

    Zhang, Hai-Ling; Sheng, Guo-Ping; Fang, Wei; Wang, Yong-Peng; Fang, Cai-Yun; Shao, Li-Min; Yu, Han-Qing

    2015-11-01

    Phosphorus accumulating organisms (PAOs) have been found to act as glycogen-accumulating organisms (GAOs) under certain conditions, thus, the deterioration in the performance of enhanced biological phosphorus removal systems is not always attributed to the proliferation of GAOs. In this work, the effects of calcium on the metabolic pathway of PAOs were explored. It was found that when the influent Ca(2+) concentration was elevated, the tendency and extent of extracellular calcium phosphate precipitation increased, and the intracellular inert Ca-bound polyphosphate was synthesized, while the microbial population remained almost unchanged. The changes in the ratios of phosphorus released/acetate uptaken, the glycogen degraded/acetate uptaken and the poly-β-hydroxyalkanoates synthesized/acetate uptaken during the anaerobic period confirm that, as the influent Ca(2+) concentration was increased, the polyphosphate-accumulating metabolism was partially shifted to the glycogen-accumulating metabolism. At an influent Ca(2+) around 50 mg/L, in addition to the extracellular calcium phosphate precipitation, the intracellular inert Ca-bound polyphosphate synthesis might also be involved in the metabolic change of PAOs. The results of the present work would be beneficial to better understand the biochemical metabolism of PAOs in enhanced biological phosphorus removal systems. PMID:26233656

  17. Process for improving phosphorus-vanadium oxide and phosphorus-vanadium-co-metal oxide catalysts

    International Nuclear Information System (INIS)

    A process is described for the improvement of a vanadium-phosphorus-oxygen catalyst having a phosphorus to vanadium atomic ratio of about 2:1 to about 0.8:1 which catalyst is present on a catalyst bed having a portion therof containing an initial exotherm of reaction. The catalyst is suitable for use in the manufacture of maleic anhydride from a feed gas stream comprising C/sub 4/ hydrocarbons, benzene, or butane which process comprises: applying to the catalyst bed, simultaneously with introduction of the feed gas stream thereon, water and a phosphorus compound in an amount sufficient to initiate (a) deactivation of the portion of the catalyst containing the initial exotherm, and (b) formation of a new exotherm downstream in the catalyst bed from the initial exotherm, and thereafter reducing or discontinuing application of the phosphorus compound at a point in time when the initial exotherm portion of the catalyst bed is still undergoing deactivation, thereby allowing the partially deactivated exotherm portion to reactivate by producing a more isothermal catalyst bed

  18. Phosphorus solubility in an acid forest soil as influenced by form of applied phosphorus and liming

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, Ann-Mari; Bergkvist, Bo; Tyler, Germund [Lund Univ. (Sweden). Dept. of Ecology

    1999-07-01

    Sedimentary phosphorus, superphosphate, and wood-ash, as well as either sedimentary phosphorus. superphosphate or ash combined with lime, were distributed in selected plots in an 80-yr-old Norway spruce forest [Picea abies (L.) Karst]. After 2 yrs, the sedimentary phosphorus had increased the oxalate/oxalic acid-extractable P in the O-horizon, and the superphosphate had increased the oxalate/oxalic acid-extractable P in the E-horizon. At first, the percolation water from the superphosphate treatment showed high P concentrations. It soon returned to control levels, however. The percolation water from the sedimentary phosphorus treatment gradually showed increased phosphate concentrations. The wood-ash increased neither the amount of extractable P nor the P concentration in the percolation water. The oxalate/oxalic acid-extractable P from the sedimentary P treatment was reduced by liming. The P concentration in the percolation water also tended to be reduced. This was perhaps due to formation of Ca phosphates in the vicinity of the lime particles. In addition, if the solubility rate was similar to the uptake rate, it could account for the decreased P concentration.

  19. Application of Wood Char in Processing Oolitic High-phosphorus Hematite for Phosphorus Removal

    Institute of Scientific and Technical Information of China (English)

    Hui-qing TANG; Yan-qi QIN; Teng-fei QI; Zhi-lei DONG; Qing-guo XUE

    2016-01-01

    Phosphorus removal from oolitic high-phosphorus hematite using direct reduction followed by melting sep-aration was investigated.At the direct reduction stage,highly volatile wood char was prepared by carbonizing j uj ube wood at 673 K for 2 h and was used as reducing agent.The results of the direct reduction tests show that at a tem-perature of 1 373 K,a char mixing ratio of 0�8,and a reduction time of 10-25 min,the briquettes reached a metal-lization degree of 80%-84% and a residual carbon content of 0�13-1�98 mass%.Phosphorus remained in the gangue as calcium phosphate after reduction.The results of the melting separation tests show that residual carbon in reduced briquette negatively affects the phosphorus content (w[P])in hot metal.When the reduced briquettes ob-tained under the aforementioned conditions were used for melting separation,hot metal suitable for basic oxygen steelmaking (w[P]<0�4 mass%)could not be obtained from metallic briquettes with a residual carbon content more than 1�0 mass%.In contrast,it could be obtained from metallic briquettes with residual carbon content less than 0�35 mass% by mixing with 2%-4% Na2 CO3 .

  20. Effect of Microwave Treatment Upon Processing Oolitic High Phosphorus Iron Ore for Phosphorus Removal

    Science.gov (United States)

    Tang, Hui-Qing; Liu, Wei-Di; Zhang, Huan-Yu; Guo, Zhan-Cheng

    2014-10-01

    Influence of microwave treatment on the previously proposed phosphorus removal process of oolitic high phosphorus iron ore (gaseous reduction followed by melting separation) has been studied. Microwave treatment was carried out using a high-temperature microwave reactor (Model: MS-WH). Untreated ore fines and microwaved ore fines were then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and thermogravimetric analysis (TGA). Thereafter, experiments on the proposed phosphorus removal process were conducted to examine the effect of microwave treatment. Results show that microwave treatment could change the microstructure of the ore fines and has an intensification effect on its gaseous reduction by reducing gas internal resistance, increasing chemical reaction rate and postponing the occurrence of sintering. Results of gaseous reduction tests using tubular furnace indicate both microwave treatment and high reduction temperature high as 1273 K (1000 °C) are needed to totally break down the dense oolite and metallization rate of the ore fines treated using microwave power of 450 W could reach 90 pct under 1273 K (1000 °C) and for 2 hours. Results of melting separation tests of the reduced ore fines with a metallization rate of 90 pct show that, in addition to the melting conditions in our previous studies, introducing 3 pct Na2CO3 to the highly reduced ore fines is necessary, and metal recovery rate and phosphorus content of metal could reach 83 pct and 0.31 mass pct, respectively.

  1. Phosphorus availability for plant uptake in a phosphorus-enriched noncalcareous sandy soil

    NARCIS (Netherlands)

    Koopmans, G.F.; Chardon, W.J.; Ehlert, P.A.I.; Dolfing, J.; Suurs, R.A.A.; Oenema, O.; Riemsdijk, van W.H.

    2004-01-01

    Mining soil phosphorus (i.e., harvesting P taken up from the soil by a crop grown without external P addition) has been proposed as a possible management strategy for P-enriched soils to decrease the risk of P leaching. We performed a pot experiment in a greenhouse where grass was cropped on a P-enr

  2. Long-term development of phosphorus and nitrogen loads through the subsurface and surface water systems of drainage basins

    Science.gov (United States)

    Darracq, AméLie; Lindgren, Georg; Destouni, Georgia

    2008-09-01

    We analyze and compare simulations and controlling processes of the past 60 years and possible future short- and long-term development of phosphorus and nitrogen loading from the Swedish Norrström drainage basin to the Baltic Sea under different inland source management scenarios. Results indicate that both point and agricultural source inputs may need to be decreased by at least 40% in order to reach a long-term sustainable 30% reduction of anthropogenic coastal nitrogen loading, as required by national environmental goals. A corresponding 20% anthropogenic phosphorus load reduction goal may be reached in the short term by analogous combined 40% source input reduction, but appears impossible to maintain as a long-term achievement by inland source abatement only. In general, realistic quantification of the slow subsurface nutrient transport and accumulation-release dynamics may be essential for accurately predicting and managing nutrient loading to surface and coastal waters.

  3. COMPARISON OF SOIL PHOSPHORUS TEST METHODS

    Directory of Open Access Journals (Sweden)

    Brigita Popović

    2010-06-01

    Full Text Available Soil-P test is obligate chemical analysis for soil productivity estimation and most frequent used method in Croatia is AL method (soil extraction by ammoniumlactate solution at pH 3.75. Howewer, in some soils AL method (especially calcareous could be inaccurate for phosphorus fertilizer recommendations and crop response could be inadequate. Hence, the aim of this research was to compare 6 different P-tests: Olsen, Morgan, Bray1, Bray 2, CAL and DL. Each of these methods had a different pH of extraction solutios: Olsen (pH 8.5, Morgan (4,8, Bray 1 and Bray 2 (2.6, CAL (4.1 DL (3.7. Aiming to compare these 7 soil tests, 360 soil samples were collected from the continental part od Croatia. The soil pH, organic matter, AL-P2O5 and % CaCO3 were analyzed. All samples were grouped according to soil pH in two groups (pHKCl 6 179 samples. Phosphorus content on the average decreased: Bray 1 > DL > AL > CAL > Bray 2> Olsen > Morgan. Significant corellations were estimeted between AL and Olsen P test (r= 0.88, AL and Bray 1 P test (r=0.68, Olsen and Bray 1 P test (r= 0,75 and CAL and DL P tests (r=0.45. In the analysed samples total phospohrus content was recorded in all samples and portion of organic phosphorus in total phosporus in soil ranged from 0.54 to 78.29 %. The developed models are very simple and useful because they can predict soil phosphurus using only one soil test data. The models were validated and showed that all recorded corelations in this study were precise and approved the aforementioned models accuracy.

  4. Enhanced biological phosphorus removal employing EDTA disodium

    Energy Technology Data Exchange (ETDEWEB)

    Bojinova, D.; Velkova, R. [Higher Inst. of Chemical Technology, Sofia (Bulgaria)

    1996-12-31

    The biological phosphorus removal is a promising alternative to the conventional chemical technologies for processing of phosphate raw materials. The object of this study was the effect of EDTA disodium on the biotreatment of tunisian phosphorite with the strain of Aspergillus niger. The incubation was carried out in two nutritive mediums, with different phosphate content. The experimental results showed that the additives of EDTA disodium in the nutritive medium increased the rate of extraction of P{sub 2}O{sub 5} and shortened significantly the time for biological leaching. 5 refs., 3 figs., 2 tabs.

  5. Elastic properties of suspended black phosphorus nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jia-Ying; Li, Yang; Zhen, Liang; Xu, Cheng-Yan, E-mail: cy-xu@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); MOE Key Laboratory of Micro-systems and Micro-structures Manufacturing, Harbin Institute of Technology, Harbin 150080 (China); Zhan, Zhao-Yao [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Li, Tie [Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

    2016-01-04

    The mechanical properties of black phosphorus (BP) nanosheets suspended over circular holes were measured by an atomic force microscope nanoindentation method. The continuum mechanic model was introduced to calculate the elastic modulus and pretension of BP nanosheets with thicknesses ranging from 14.3 to 34 nm. Elastic modulus of BP nanosheets declines with thickness, and the maximum value is 276 ± 32.4 GPa. Besides, the effective strain of BP ranges from 8 to 17% with a breaking strength of 25 GPa. Our results show that BP nanosheets serve as a promising candidate for flexible electronic applications.

  6. Phosphorus leaching in relation to soil type and soil phosphorus content.

    Science.gov (United States)

    Djodjic, Faruk; Börling, Katarina; Bergström, Lars

    2004-01-01

    Phosphorus losses from arable soils contribute to eutrophication of freshwater systems. In addition to losses through surface runoff, leaching has lately gained increased attention as an important P transport pathway. Increased P levels in arable soils have highlighted the necessity of establishing a relationship between actual P leaching and soil P levels. In this study, we measured leaching of total phosphorus (TP) and dissolved reactive phosphorus (DRP) during three years in undisturbed soil columns of five soils. The soils were collected at sites, established between 1957 and 1966, included in a long-term Swedish fertility experiment with four P fertilization levels at each site. Total P losses varied between 0.03 and 1.09 kg ha(-1) yr(-1), but no general correlation could be found between P concentrations and soil test P (Olsen P and phosphorus content in ammonium lactate extract [P-AL]) or P sorption indices (single-point phosphorus sorption index [PSI] and P sorption saturation) of the topsoil. Instead, water transport mechanism through the soil and subsoil properties seemed to be more important for P leaching than soil test P value in the topsoil. In one soil, where preferential flow was the dominant water transport pathway, water and P bypassed the high sorption capacity of the subsoil, resulting in high losses. On the other hand, P leaching from some soils was low in spite of high P applications due to high P sorption capacity in the subsoil. Therefore, site-specific factors may serve as indicators for P leaching losses, but a single, general indicator for all soil types was not found in this study. PMID:15074820

  7. GREENHOUSE GASES AND AGRICULTURE

    Science.gov (United States)

    Agriculture ranks third in its contribution to Earth's anthropogenically nhanced greenhouse effect. Energy use and production and chlorofluorocarbons are anked first and second, respectively.) pecifically, greenhouse gas sources and inks are increased, and sinks are decreased, by...

  8. Agricultural science and ethics

    DEFF Research Database (Denmark)

    Gjerris, Mickey; Vaarst, Mette

    2014-01-01

    Humans live in constant interaction with nature. That is part and parcel of being a biological creature on this planet. On one hand, humans exploit the available resources to survive, and at the same time, humans are deeply dependent on the continued capacity of nature to sustain their lives......, about 20 % of the world's coral reefs and 35 % of the mangrove areas were lost (Millennium Ecosystem Assessment 2005). In the following, the development of agricultural science will be sketched out and the role of ethics in agricultural science will be discussed. Then different views of nature that have...... shaped agriculture and the role of science in agriculture will be discussed by analyzing some of the presumptions behind the concept of ecosystem services and the way animals are viewed. Finally, the concepts of animal welfare and sustainability will be explored to show how they make vivid the connection...

  9. Agricultural Health and Safety

    Science.gov (United States)

    ... health and safety program. Contact your state or territorial health department or use this directory of local ... producers, small business owners, youth, consumers, and rural communities nationwide. NIOSH Agricultural Safety and Health Centers conduct ...

  10. Agricultural Producer Certificates

    Data.gov (United States)

    Montgomery County of Maryland — A Certified Agricultural Producer, or representative thereof, is an individual who wishes to sell regionally-grown products in the public right-of-way. A Certified...

  11. Department of Agriculture

    Science.gov (United States)

    ... and Natural Resources Ethics Farm Bill Food and Nutrition Food Safety Forestry Housing Assistance Laws and Regulations Organic Agriculture Outreach Plant Health Research and Science Rural and Community Development Rural Opportunities Trade Travel and Recreation USDA for ...

  12. Collaboration in Agricultural Education.

    Science.gov (United States)

    Peterson, Roland L.; And Others

    1995-01-01

    Theme articles discuss environment, food, agriculture, and renewal resources as they relate to science education, learning partnerships, collaboration in Kyrghyzstan, leadership development, opportunities for collaboration, networking, and the creation of a shared course between agribusiness and biology. (JOW)

  13. Agricultural Research Service

    Science.gov (United States)

    ... Help Popular Topics Content Popular Topics AgResearch Magazine Bee Health Image Gallery Nutrient Data Tools Plant Hardiness ... Large Display of USG Support for Agriculture and Nutrition Open Data Knowledge and Passion: A Student Intern’s ...

  14. Organic agriculture in the Netherlands

    NARCIS (Netherlands)

    Sukkel, W.; Hommes, M.

    2009-01-01

    Dutch organic agriculture has unique characteristics and peculiarities. It is still a relatively small sector compared to conventional agriculture in the Netherlands. However, its market share is growing and organic agriculture leads the way in terms of sustainability and innovations

  15. County-level estimates of nitrogen and phosphorus from commercial fertilizer for the Conterminous United States, 1987–2006

    Science.gov (United States)

    Gronberg, Jo Ann M.; Spahr, Norman E.

    2012-01-01

    The U.S. Geological Survey’s National Water-Quality Assessment program requires nutrient input for analysis of the national and regional assessment of water quality. Detailed information on nutrient inputs to the environment are needed to understand and address the many serious problems that arise from excess nutrients in the streams and groundwater of the Nation. This report updates estimated county-level farm and nonfarm nitrogen and phosphorus input from commercial fertilizer sales for the conterminous United States for 1987 through 2006. Estimates were calculated from the Association of American Plant Food Control Officials fertilizer sales data, Census of Agriculture fertilizer expenditures, and U.S. Census Bureau county population. A previous national approach for deriving farm and nonfarm fertilizer nutrient estimates was evaluated, and a revised method for selecting representative states to calculate national farm and nonfarm proportions was developed. A national approach was used to estimate farm and nonfarm fertilizer inputs because not all states distinguish between farm and nonfarm use, and the quality of fertilizer reporting varies from year to year. For states that distinguish between farm and nonfarm use, the spatial distribution of the ratios of nonfarm-to-total fertilizer estimates for nitrogen and phosphorus calculated using the national-based farm and nonfarm proportions were similar to the spatial distribution of the ratios generated using state-based farm and nonfarm proportions. In addition, the relative highs and lows in the temporal distribution of farm and nonfarm nitrogen and phosphorus input at the state level were maintained—the periods of high and low usage coincide between national- and state-based values. With a few exceptions, nonfarm nitrogen estimates were found to be reasonable when compared to the amounts that would result if the lawn application rates recommended by state and university agricultural agencies were used. Also

  16. Brazil Agriculture Policy Review

    OpenAIRE

    Quiroga, Jose; Brooks, Jonathan; Melyukhina, Olga

    2005-01-01

    In June 2005, OECD members met with senior government officials from Brazil to discuss Brazilian agricultural policies and future directions, as a part of a comprehensive agricultural policy review. Ongoing dialogue with Brazil on policy issues is important to fostering a better understanding of global challenges and opportunities that lie ahead. Results of the review will be published by the OECD in 2005. This policy note provides a preview of key findings.

  17. World competitiveness and agriculture

    Directory of Open Access Journals (Sweden)

    J. van Zyl

    1997-07-01

    Full Text Available Against the background of a changing environment in which market factors and greater world trade and competitiveness are increasingly becoming the only criteria for success, a framework for the analysis of world competitiveness is initially developed. This is followed by a discussion on the growth of productivity in agriculture, as well as an exposition of the role of agricultural research. Thirdly, price factors and the terms of trade are discussed, followed by a summary of policy implications.

  18. HOMOEOPATHY IN AGRICULTURE

    OpenAIRE

    Singhania, Pawan Kumar; SINGHANIA, ARCHANA

    2014-01-01

    Homoeopathy medicines have been found to be effective in human organisms. Research and application of Homoeopathy drugs in agriculture is slowly finding place. The mode of action of Homoeopathy remedies and simillinum of drug pictures for use in agriculture; basic principles of Homoeopathy and drug administration are discussed. Significant results have been observed using Homoeopathy medicines to fight stress conditions during wet conditions; during hot and dry conditions; in improving germin...

  19. Agriculture Sector Risk Management

    OpenAIRE

    Viktorija Stasytytė; Viktorija Dužinskytė

    2016-01-01

    Agriculture sector is characterized by a particular specificity that is not considered in other fields and because of that agriculture sector is defined as highly risky sector. Response to risk is still very im-portant and responsible activity in this field. According to this, the process and applied strategies of risk management make and ensure that the sector activity and operations are more stable and effective. The aim of the article reflects the need to distinguish the most appropriate a...

  20. Potential impact of dietary choices on phosphorus recycling and global phosphorus footprints: the case of the average Australian city

    Directory of Open Access Journals (Sweden)

    Genevieve Metson

    2016-08-01

    Full Text Available Changes in human diets, population increase, changes in farming practices, and globalized food chains have led to dramatic increases in the demand for phosphorus fertilizers. Long-term food security and water quality are however threatened by such increased phosphorus consumption because the world’s main source, phosphate rock, is an increasingly scarce resource. At the same time losses of phosphorus from farms and cities have caused widespread water pollution. As one of the major factors contributing to increased phosphorus demand, dietary choices can play a key role in changing our resource consumption pathway. Importantly, the effects of dietary choices on phosphorus management are two-fold: First, dietary choices affects a person or region’s ‘phosphorus footprint’ – the magnitude of mined phosphate required to meet food demand. Second, dietary choices affect the magnitude of phosphorus content in human excreta, and hence the recycling- and pollution-potential of phosphorus in sanitation systems. When considering options and impacts of interventions at the city scale (e.g. potential for recycling, dietary changes may be undervalued as a solution towards phosphorus sustainability. In an average Australian city for example, a vegetable-based diet could marginally increase phosphorus in human excreta (8% increase. However such a shift could simultaneously dramatically decrease the mined phosphate required to meet the city resident’s annual food demand by 72%. Taking a multi-scalar perspective is therefore key to fully exploring dietary choices as one of the tools for sustainable phosphorus management.

  1. Anthropogenic phosphorus flow analysis of Hefei City, China

    International Nuclear Information System (INIS)

    The substance flow analysis (SFA) method was employed to examine phosphorus flow and its connection to water pollution in the city of Hefei, China, in 2008. As human activity is the driving force of phosphorus flux from the environment to the economy, the study provides a conceptual framework for analyzing an anthropogenic phosphorus cycle that includes four stages: extraction, fabrication and manufacturing, use, and waste management. Estimates of phosphorus flow were based on existing data as well as field research, expert advice, local accounting systems, and literature. The total phosphorus input into Hefei in 2008 reached 7810 tons, mainly as phosphate ore, chemical fertilizer, pesticides, crops and animal products. Approximately 33% of the total phosphorus input left the area, and nearly 20% of that amount was discharged as waste to surface water. Effluent containing excessive fertilizer from farming operations plays an important role in phosphorus overloads onto surface water; the other major emission source is sewage discharge. We also provide suggestions for reducing phosphorus emissions, for example reducing fertilizer use, recycling farming residues, and changing human consumption patterns.

  2. The total phosphorus budget of a peat-covered catchment

    Science.gov (United States)

    Worrall, Fred; Moody, Catherine S.; Clay, Gareth D.; Burt, Tim P.; Rose, Rob

    2016-07-01

    Although many studies have considered the carbon or greenhouse gas budgets of peat ecosystems, only a few have considered the nutrient budget of peat soils, and this, in turn, has limited the ability of studies to consider the impact of changes in climate and atmospheric deposition on the phosphorus budget of a peat soil. This study considered the total phosphorus (P) budget of an upland peat-covered catchment over the period 1993 to 2012. The study has shown (i) total atmospheric deposition of phosphorus varied from 62 to 175 kg P/km2/yr; (ii) the carbon:phosphorus ratio of the peat profile declines significantly from values in the litter layer (C:P = 1326) to approximately constant at 30 cm depth (C:P = 4240); (iii) the total fluvial flux of phosphorus varied from 49 to 111 kg P/km2/yr, of which between 45 and 77% was dissolved P; and (iv) the total phosphorus sink varied from -5.6 to +71.7 kg P/km2/yr with a median of +29.4 kg P/km2/yr, which is within the range of the estimated long-term accumulation rate of phosphorus in the peat profile of between 3 and 32 kg P/km2/yr. The phosphorus budget of the peat ecosystem relies on rapid recycling near the soil surface, and this means that any vegetation management may critically deprive the ecosystem of this nutrient.

  3. Environmental Benefits and Burdens of Phosphorus Recovery from Municipal Wastewater.

    Science.gov (United States)

    Bradford-Hartke, Zenah; Lane, Joe; Lant, Paul; Leslie, Gregory

    2015-07-21

    The environmental benefits and burdens of phosphorus recovery in four centralized and two decentralized municipal wastewater systems were compared using life cycle assessment (LCA). In centralized systems, phosphorus recovered as struvite from the solids dewatering liquid resulted in an environmental benefit except for the terrestrial ecotoxicity and freshwater eutrophication impact categories, with power and chemical use offset by operational savings and avoided fertilizer production. Chemical-based phosphorus recovery, however, generally required more resources than were offset by avoided fertilizers, resulting in a net environmental burden. In decentralized systems, phosphorus recovery via urine source separation reduced the global warming and ozone depletion potentials but increased terrestrial ecotoxicity and salinization potentials due to application of untreated urine to land. Overall, mineral depletion and eutrophication are well-documented arguments for phosphorus recovery; however, phosphorus recovery does not necessarily present a net environmental benefit. While avoided fertilizer production does reduce potential impacts, phosphorus recovery does not necessarily offset the resources consumed in the process. LCA results indicate that selection of an appropriate phosphorus recovery method should consider both local conditions and other environmental impacts, including global warming, ozone depletion, toxicity, and salinization, in addition to eutrophication and mineral depletion impacts. PMID:26121005

  4. Ups and Downs of the Yellow Phosphorus Market in 2007

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 1 Surplus capacity The rapid growth of the economy in China promoted drastic development of the yellow phosphorus sector from 1985 to 2004. The capacity of yellow phosphorus expanded rapidly from 100 000 t/a in 1985 to 1.2 million t/a in 2004 with an average annual growth of around 14.0%.

  5. Removal of Phosphorus from Silicon Melts by Vacuum Refining

    OpenAIRE

    Xakalashe, Buhle Sinaye

    2011-01-01

    Induction vacuum refining testwork has been carried out for the removal of phosphorus from silicon melts. This work is of interest for the production of solar-grade silicon, since phosphorus is hard to remove from silicon and an important impurity in solar cells.

  6. Biological Phosphorus Removal in a Moving Bed Biofilm Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Helness, Herman

    2007-09-15

    The scope of this study was to investigate use of the moving bed biofilm reactor (MBBR) process for biological phosphorus removal. The goal has been to describe the operating conditions required for biological phosphorus and nitrogen removal in a MBBR operated as a sequencing batch reactor (SBR), and determine dimensioning criteria for such a process

  7. Phosphorus Removal By Silage Corn In Southern Idaho

    Science.gov (United States)

    Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much phosphorus and other nutrients are being recovered under Idaho conditions. The objective of the study is to estimate p...

  8. Phosphorus recovery from pig manure solids prior to land application

    Science.gov (United States)

    Land disposal of pig manure is an environmental concern due to an imbalance of the nitrogen to phosphorus (N:P) ratio for crop production, leading to excess phosphorus (P) in soils and potential risks of water pollution. A process called “quick wash” was investigated for its feasibility to extract ...

  9. The release of dissolved phosphorus from lake sediments.

    NARCIS (Netherlands)

    Boers, P.C.M.

    1991-01-01

    Chapter 1. Introduction: Eutrophication is one of the world's major water quality problems. Attempts to alleviate eutrophication of lakes have involved the control of phosphorus loadings. In such cases, an internal loading of phosphorus from the sediments may retard an improvement o

  10. Indian Agricultural Marketing- A Review

    OpenAIRE

    Shakeel-Ul-Rehman; M. SELVARAJ; M. Syed Ibrahim

    2012-01-01

    Agriculture in India has directly or indirectly continued to be the source of livelihood to majority of the population. Indian agriculture has seen a lot of changes in its structure. India, predominantly an agricultural economy, has healthy signs of transformation in agriculture and allied activities. India has seen agriculture as a precious tool of economic development as other sectors of production depend on it. Efficient backward and forward integration with agriculture has led to globally...

  11. FAPRI 2000 World Agricultural Outlook

    OpenAIRE

    Babcock, Bruce A.; Beghin, John C.; Mohanty, Samarendu; Frank H. Fuller; Jacinto F. Fabiosa; Kaus, Phillip J.; Fang, Cheng; Hart, Chad E.; Kovarik, Karen; Womack, Abner W.; Young, Robert E., II; Suhler, Gregg; Patrick C. Westhoff; Trujillo, Joe; Brown, D. Scott

    2000-01-01

    The Food and Agricultural Policy Research Institute (FAPRI) prepares a preliminary agricultural outlook on world agricultural production, consumption, and trade every fall. This is followed by an outside review, re-evaluation of projections, and completion of the final baseline in January. The FAPRI 2000 World Agricultural Outlook presents these final projections for world agricultural markets. A companion volume, the FAPRI 2000 U.S. Agricultural Outlook, presents the U.S. component of the ba...

  12. Ghana Agricultural Sector Risk Assessment

    OpenAIRE

    Choudhary, Vikas; D'Alessandro, Stephen

    2015-01-01

    Improved agricultural risk management is one of the core enabling actions of the Group of Eight’s (G-8’s) New Alliance for Food Security and Nutrition. The Agricultural Risk Management Team (ARMT) of the Agriculture and Environment Services Department of the World Bank conducted an agricultural sector risk assessment to better understand the dynamics of agricultural risks and identify appropriate responses, incorporate agricultural risk perspective into decision-making, and bui...

  13. Land-use intensification impact on phosphorus fractions in highly weathered tropical soils

    Science.gov (United States)

    Maranguit, Deejay; Guillaume, Thomas; Kuzyakov, Yakov

    2016-04-01

    Deforestation and land-use intensification in tropics have increased over the past decades, driven by the demand for agricultural products. Despite the fact that phosphorus (P) is one of the main limiting nutrients for agricultural productivity in the tropics, the effect of land-use intensification on P availability remains unclear. The objective was to assess the impacts of land-use intensification on soil inorganic and organic P fractions of different availability (Hedley sequential fractionation) and P stocks in highly weathered tropical soils. We compared the P availability under extensive land-use (rubber agroforest) and intensive land-use with moderate fertilization (rubber monoculture plantations) or high fertilization (oil palm monoculture plantations) in Indonesia. The phosphorus stock was dominated by inorganic forms (60 to 85%) in all land-use types. Fertilizer application increased easily-available inorganic P (i.e., H2O-Pi, NaHCO3-Pi) in intensive rubber and oil palm plantations compared to agroforest. However, the easily-available organic P (NaHCO3-extractable Po) was reduced by half under oil palm and rubber. The decrease of moderately available and non-available P by land-use intensification means that fertilization maintains only short-term soil fertility that is not sustainable in the long run due to the depletion of P reserves. The mechanisms of this P reserve depletion are: soil erosion (here assessed by C/P ratio), mineralization of soil organic matter (SOM) and export of P with yield products. Easily-available P fractions (i.e., H2O-Pi, NaHCO3-Pi and Po) and total organic P were strongly positively correlated with carbon content suggesting that SOM plays a critical role in maintaining P availability. Therefore, the ecologically based management is necessary in mitigating SOM losses to increase the sustainability of agricultural production in P limited highly weathered tropical soils.

  14. Phosphorus isothermal adsorption characteristics of mulch of bioretention

    Directory of Open Access Journals (Sweden)

    Mei Ying

    2012-01-01

    Full Text Available This study aims to identify mulch of bioretention which has high phosphorus sorption capacity. The phosphorus adsorption characteristics of five types of mulch of bioretention are studied by three isothermal adsorption experiments. Results show that the Langmuir eqution is suitable for describing absorption characteristics of five types of mulch. The positive values of Gibbs free energy for phosphorus indicate that the phosphorus biosorption by five mulches is a non-spontaneous process, and the values of mean sorption free energy of mulch are less than 8 kJ/mol, which proves that the adsorption process can be dominated by physical forces. The vermiculite is the better mulch of bioretention based on high phosphorus removal capacity.

  15. Soil phosphorus and the ecology of lowland tropical forests

    Science.gov (United States)

    Turner, Ben

    2016-04-01

    In this presentation I will explore the extent to which phosphorus influences the productivity, diversity, and distribution of plant species in tropical forests. I will highlight the range of soils that occur in tropical forests and will argue that pedogenesis and associated phosphorus depletion is a primary driver of forest diversity over long timescales. I will draw on data from a regional-scale network of forest dynamics plots in Panama to show that tree species distributions are determined predominantly as a function of dry season intensity and soil phosphorus availability, and will suggest potential mechanistic explanations for this pattern in relation to phosphorus acquisition. Finally, I will present observational and experimental evidence from Panama to show how phosphorus, nitrogen, and potassium, limit plant productivity and microbial communities on strongly-weathered soils in the lowland tropics.

  16. Influence of phosphorus on point defects in an austenitic alloy

    International Nuclear Information System (INIS)

    The influence of phosphorus on points defects clusters has been studied in an austenitic alloy (Fe/19% at. Cr/13% at. Ni). Clusters are observed by transmission electron microscopy. After quenching and annealing, five types of clusters produced by vacancies or phosphorus-vacancies complexes are observed whose presence depends on cooling-speed. Vacancy concentration (with 3.6 10-3 at. P) in clusters is about 10-5 and apparent vacancy migration is 2± 0.1 eV. These observations suggest the formation of metastable small clusters during cooling which dissociate during annealing and migrate to create the observed clusters. With phosphorus, the unfrequent formation of vacancy loops has been observed during electron irradiation. Ions irradiations show that phosphorus does not favour nucleation of interstitial loops but slowers their growth. It reduces swelling by decreasing voids diameter. Phosphorus forms vacancy complexes whose role is to increase the recombination rate and to slow vacancy migration

  17. Towards a nutrient export risk matrix approach to managing agricultural pollution at source

    OpenAIRE

    Hewett, C. J. M.; Quinn, P. F.; P. G. Whitehead; Heathwaite, A. L.; N. J. Flynn

    2004-01-01

    A generic Nutrient Export Risk Matrix (NERM) approach is presented. This provides advice to farmers and policy makers on good practice for reducing nutrient loss and, hopefully, persuades them to implement such measures. Combined with a range of nutrient transport modelling tools and field experiments, NERMs can play an important role in reducing nutrient export from agricultural land. The Phosphorus Export Risk Matrix (PERM) is presented as an example NERM. The PERM integrates hydrologica...

  18. Riparian buffer strips as a multifunctional management tool in agricultural landscapes: Introduction to the special collection

    OpenAIRE

    Stutter, M. I.; Chardon, W.J.; B. Kronvang

    2012-01-01

    Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented “edge of field” mitigation measure assumed to provide an effective physical barrier against nitrogen (N), phosphorus (P), and sediment transfer. To ease the legislative process, these buffers are often narrow mandatory strips along streams...

  19. Towards a nutrient export risk matrix approach to managing agricultural pollution at source

    OpenAIRE

    Hewett, C. J. M.; Quinn, P. F.; P. G. Whitehead; Heathwaite, A. L.; N. J. Flynn

    2004-01-01

    International audience A generic Nutrient Export Risk Matrix (NERM) approach is presented. This provides advice to farmers and policy makers on good practice for reducing nutrient loss and, hopefully, persuades them to implement such measures. Combined with a range of nutrient transport modelling tools and field experiments, NERMs can play an important role in reducing nutrient export from agricultural land. The Phosphorus Export Risk Matrix (PERM) is presented as an example NERM. The PERM...

  20. Phosphorus stress effects on assimilation of nitrate

    International Nuclear Information System (INIS)

    An experiment was conducted to investigate alterations in uptake and assimilation of NO3- by phosphorus-stressed plants. Young tobacco plants (Nicotiana tabacum [L.], cv NC 2326) growing in solution culture were derived of an external phosphorus (P) supply for 12 days. On selected days, plants were exposed to 15NO3- during the 12 hour light period to determine changes in NO3- assimilation as the P deficiency progressed. Decreased whole-plant growth was evident after 3 days of P deprivation and became more pronounced with time, but root growth was unaffected until after day 6. Uptake of 15NO3- per gram root dry weight and translocation of absorbed 15NO3- out of the root were noticeably restricted in -P plants by day 3, and effects on both increased in severity with time. Whole-plant reduction of 15NO3- and 15N incorporation into insoluble reduced-N in the shoot decreased after day 3. Although the P limitation was associated with a substantial accumulation of amino acids in the shoot, there was no indication of excessive accumulation of soluble reduced-15N in the shoot during the 12 hour 15NO3- exposure periods. The results indicate that alterations in NO3- transport processes in the root system are the primary initial responses limiting synthesis of shoot protein in P-stressed plants. Elevated amino acid levels evidently are associated with enhanced degradation of protein rather than inhibition of concurrent protein synthesis

  1. Ruzigrass affecting soil-phosphorus availability

    Directory of Open Access Journals (Sweden)

    Alexandre Merlin

    2013-12-01

    Full Text Available The objective of this work was to evaluate the effectiveness of ruzigrass (Urochloaruziziensis in enhancing soil-P availability in areas fertilized with soluble or reactive rock phosphates. The area had been cropped for five years under no-till, in a system involving soybean, triticale/black-oat, and pearl millet. Previously to the five-year cultivation period, corrective phosphorus fertilization was applied once on soil surface, at 0.0 and 80 kg ha-1 P2O5, as triple superphosphate or Arad rock phosphate. After this five-year period, plots received the same corrective P fertilization as before and ruzigrass was introduced to the cropping system in the stead of the other cover crops. Soil samples were taken (0-10 cm after ruzigrass cultivation and subjected to soil-P fractionation. Soybean was grown thereafter without P application to seed furrow. Phosphorus availability in plots with ruzigrass was compared to the ones with spontaneous vegetation for two years. Ruzigrass cultivation increased inorganic (resin-extracted and organic (NaHCO3 soil P, as well as P concentration in soybean leaves, regardless of the P source. However, soybean yield did not increase significantly due to ruzigrass introduction to the cropping system. Soil-P availability did not differ between soluble and reactive P sources. Ruzigrass increases soil-P availability, especially where corrective P fertilization is performed.

  2. Review of scenario analyses to reduce agricultural nitrogen and phosphorus loading to the aquatic environment

    DEFF Research Database (Denmark)

    Hashemi, Fatemeh; Olesen, Jørgen Eivind; Dalgaard, Tommy;

    2016-01-01

    within stream or river catchments have considerable influence on nutrient transport, transformation and retention processes that all eventually affect loadings to vulnerable aquatic environments. Therefore, in order to address options to reduce nutrient loadings, quantitative assessment of their effects...

  3. Agricultural use of organic wastes as source of nitrogen and phosphorus: risks and opportunities

    OpenAIRE

    Requejo Mariscal, María Isabel

    2015-01-01

    El nitrógeno (N) y el fósforo (P) son nutrientes esenciales en la producción de cultivos. El desarrollo de los fertilizantes de síntesis durante el siglo XX permitió una intensificación de la agricultura y un aumento de las producciones pero a su vez el gran input de nutrientes ha resultado en algunos casos en sistemas poco eficientes incrementando las pérdidas de estos nutrientes al medio ambiente. En el caso del P, este problema se agrava debido a la escasez de reservas de roca fosfórica ne...

  4. Phosphorus dynamics in lowland streams as a response to climatic, hydrological and agricultural land use gradients

    DEFF Research Database (Denmark)

    Goyenola, G.; Meerhoff, M.; Teixeira-de Mello, F.;

    2015-01-01

    contrasting climate and hydrological regimes (temperate Denmark and subtropical Uruguay). We applied two alternative nutrient sampling programmes (high frequency composite sampling and low frequency instantaneous-grab sampling) and three alternative methods to estimate exported P from the catchments. A source...

  5. Retention and transport of nutrients in a mature agricultural impoundment

    Science.gov (United States)

    Powers, S. M.; Julian, J. P.; Doyle, M. W.; Stanley, E. H.

    2013-03-01

    Small impoundments intended for irrigation, livestock watering, and hydropower are numerous in agricultural regions of the world. Many of these artificial water bodies are well positioned to intercept fertilizer runoff and pollutants but could be vulnerable to long-term sedimentation, management intervention, or failure. We examined solute retention in a mature, sediment-filled, run-of-river impoundment created by a small, >100 year old dam in agricultural Wisconsin, United States. To do so, we measured instantaneous net fluxes of inorganic and organic solutes through the system, which contained wetlands. The impoundment was a persistent net sink for sulfate and, during the warm season only, a net sink for nitrate, ammonium, and soluble reactive phosphorus. There was also a negative relationship between nitrate and sulfate retention, suggestive of nitrate-stimulated sulfate production. Impoundment hydraulics were then altered by a management manipulation (dam removal) that caused mean water travel time to decrease by approximately 40%. Following manipulation, autoregressive modeling of solute time series indicated a decrease in mean net retention of nitrate, sulfate, ammonium, and soluble reactive phosphorus. There was also a decrease in the variability (coefficient of variation) of instantaneous net exports of dissolved organic nitrogen and dissolved organic phosphorus. These biogeochemical changes were consistent with predictions based on hydraulics (reduced water travel time), with the exception of ammonium release immediately following reservoir dewatering. Our results emphasize the biogeochemical importance of reservoir-wetland ecosystems, which are expanding with impoundment sedimentation but are threatened by infrastructure aging. We suggest that reservoir wetlands be considered in the management of dams and surface water pollution.

  6. Biological phosphorus and nitrogen removal in a single sludge system

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Hans

    1996-05-01

    The primary aim of this thesis was to investigate the process stability of a single sludge activated system designed for the combined operation of enhanced biological phosphorus removal (EBPR) and nitrogen removal. A pilot plant at the Sjoelunda wastewater treatment plant in Malmoe, Sweden, has formed the basis for the investigation. The pilot plant study showed that the concentration of total phosphorus on average was low in the effluent, below 0.5 mg P/l. Simultaneously with the highest concentrations of phosphorus in the effluent, the lowest COD/P ratios in the effluent were recorded. A recurrent pattern of high concentrations of phosphorus was observed every year in July, which is the industrial holiday month in Sweden. Other instances of increased phosphorus concentrations in the secondary effluent illustrate the effect of prolonged periods of rain. Increasing flow rates due to rain lead to a dilution and a change in the composition of the COD in the influent wastewater. The COD/P and VFA/P ratios decrease with decreasing concentrations of COD. It was also shown that high removal ratios of both nitrogen and phosphorus during long periods are possible. The nitrogen removal was stable during the whole investigated period, whereas the phosphorus removal was unstable during prolonged periods with low concentrations of COD in the influent water. The combined biological phosphorus and nitrogen removal process implies that during these periods the risk of recirculating nitrate to the anaerobic reactor increases. Such a recirculation both stabilizes the nitrogen removal and withdraws some of the readily degradable organic material from the bio-P bacteria. The main conclusion of this study is that a phosphorus limited EBPR process can cope with the day to day variations, but occasionally, measures have to be taken if the demands for phosphorus removal are stringent. 49 refs, 8 figs, 1 tab

  7. Seasonal Phosphorus Dynamics in Turfgrass of Different Purposes

    Directory of Open Access Journals (Sweden)

    Mirjana Herak Ćustić

    2016-05-01

    Full Text Available Phosphorus (P is a component of phospholipids, nucleic acids and molecules that store energy. It increases yield and water and nutrients use efficiency. Phosphorus turfgrass content is essential for root development, and, indirectly, nutrient uptake. The aim of this research was to determine soil and turfgrass blade phosphorus dynamics on two recreational (parks Bundek and Jarun and two sports (Hippodrome and SP Mladost turfgrasses in the city of Zagreb and determine adequate fertilization. Soil and plant material sampling was performed three times during the growing season 2012 in each of the four investigated locations. The results showed that, generally, soil phosphorus content was low or even turfgrass blade phosphorus content was on the lower end of optimal supply range. Soil phosphorus values ranged from 1.78 to 6.78 mg P2O5 100 g-1, while turfgrass blade phosphorus content ranged from 0.15 to 0.45 % P. Sampling time does not affect turfgrass blade phosphorus content. Due to the particularly low soil and turfgrass blade phosphorus status, special attention when designing the fertilization program should be given to phosphorus application with at least 10 g of P2O5 m-2 in the early spring, and, if necessary, with 1 g of P2O5 m-2 during the growing season. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

  8. Nitrogen and phosphorus intake by phytoplankton in the Xiamen Bay

    Science.gov (United States)

    Lin, Cai; Li, Hui; He, Qing; Xu, Kuncan; Wu, Shengsan; Zhang, Yuanbiao; Chen, Jinmin; Chen, Baohong; Lin, Libin; Lu, Meiluan; Chen, Weifen; Tang, Rongkun; Ji, Weidong

    2010-01-01

    This paper describes a time series experiment examining the nitrogen and phosphorus intake of natural phytoplankton communities by a microcosms approach. Seawater samples containing natural phytoplankton communities were collected from waters around Baozhu Islet in inner Xiamen Bay and around Qingyu Islet in the outer bay. The goal was to elucidate the relationship between phytoplankton population enhancement, the biological removal of nitrogen and phosphorus from the seawater, and the phytoplankton nitrogen and phosphorus intake ratio based on nitrogen and phosphorus removal from seawater by phytoplankton, to provide a basis for detecting prewarning conditions for red tide and the assessment of red tide events. Two key results were obtained: 1. During the experiment, the nitrogen and phosphorus seawater concentrations in samples from these two sites were negatively and closely correlated to the logarithm of the phytoplankton cell concentration and to the value of the apparent oxygen increment. The ratio of the intake coefficients was 3.5:1 for phosphorus and 1.1:1 for nitrogen for the phytoplankton between these samples from around Baozhu Islet and Qingyu Islet, respectively. This indicates that the intake capabilities of phytoplankton for nitrogen in the two waters are essentially identical. However, for phosphorus, the capability was much higher in the Baozhu Islet waters than the Qingyu Islet waters. In other words, the phytoplankton in Qingyu Islet waters produced more biomass while consuming the same amount of phosphorus as the other waters; 2. The phytoplankton nitrogen and phosphorus intake ratio from the Baozhu Islet and Qingyu Islet waters was 20:1 and 36:1, respectively. The latter waters had a significantly higher ratio than the former and both were higher than the Redfield Ratio. These results indicate that nitrogen and phosphorus intake ratios by phytoplankton can vary significantly from region to region.

  9. Sediment and Phosphorus losses by Surface Runoff from a Catchment in the Humid Pampa Landscape, Argentina Republic

    Science.gov (United States)

    Méndez M., A.; Díaz E., L.; Lenzi M., L.; Lado, M.; Vidal-Vázquez, E.

    2015-04-01

    The estimation of sediment and phosphorus transfers from soil into watersheds as a result of agricultural activity is a key aspect for characterizing the sustainability of current land use systems. The objective of the present study was to quantify the temporal evolution of suspended sediment and dissolved phosphorus losses from the upper basin of the Gualeguaychú River. The studied catchment has an area of 483 Km2 and is located in the Entre Ríos province, Argentina Republic. The climate is subtropical humid with average annual rainfall of 1200 mm. Soils are characterized by very low infiltration rates. Land use was assessed by remote sensing and GIS tools, and consists of: 31% abandoned rice fields, 20% naturalized fields, 20% soybean (second cycle), 10% soybean (first cycle), 7% rice, 4% Pasture, and the remaining 7% is devoted to civil and road works, native forests and other crops. Low soil infiltration capacity, together with landscape geomorphological traits of the studied landscape and zonal rainfall regime, typically originates periods with high surface runoff volumes, mainly in autumn, spring and summer months. The study was conducted during a period of eight years. Instantaneous water flow measurements (discharge) were estimated in a control section of Gualeguaychú River from hydrometer reading and the rating curve of height-flow. In addition, 134 water samples of 2000 cm3 were collected during the study period to analyze the concentration of suspended sediments and dissolved phosphorus. The instantaneous flow was estimated with the hydrometer reading and the application of curve of height - flow. The discharge range was from 0.14 to 128 m3/sec, indicating a high variability in the response of the catchment to seasonal rainfall. On average suspended sediment and dissolved phosphorus losses of the experimental catchment were 1.42 Mg and 0.335 Kg per hectare/year, respectively. It was also shown that few events of high rainfall that generate excess

  10. Efficiency of domestic wastewater treatment plant for agricultural reuse

    Directory of Open Access Journals (Sweden)

    Claudinei Fonseca Souza

    2015-07-01

    Full Text Available The increasing demand for water has made the treatment and reuse of wastewater a topic of global importance. This work aims to monitor and evaluate the efficiency of a wastewater treatment plant’s (WWTP physical and biological treatment of wastewater by measuring the reduction of organic matter content of the effluent during the treatment and the disposal of nutrients in the treated residue. The WWTP has been designed to treat 2500 liters of wastewater per day in four compartments: a septic tank, a microalgae tank, an upflow anaerobic filter and wetlands with cultivation of Zantedeschia aethiopica L. A plant efficiency of 90% of organic matter removal was obtained, resulting in a suitable effluent for fertigation, including Na and Ca elements that showed high levels due to the accumulation of organic matter in the upflow anaerobic filter and wetlands. The WWTP removes nitrogen and phosphorus by the action of microalgae and macrophytes used in the process. The final effluent includes important agricultural elements such as nitrogen, phosphorus, calcium and potassium and, together with the load of organic matter and salts, meets the determination of NBR 13,969/1997 (Standard of the Brazilian Technical Standards Association for reuse in agriculture, but periodic monitoring of soil salinity is necessary.

  11. Improving phosphorus availability in an acid soil using organic amendments produced from agroindustrial wastes.

    Science.gov (United States)

    Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab

    2014-01-01

    In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments. PMID:25032229

  12. Improving phosphorus availability in an acid soil using organic amendments produced from agroindustrial wastes.

    Science.gov (United States)

    Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab

    2014-01-01

    In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments.

  13. Improving Phosphorus Availability in an Acid Soil Using Organic Amendments Produced from Agroindustrial Wastes

    Directory of Open Access Journals (Sweden)

    Huck Ywih Ch’ng

    2014-01-01

    Full Text Available In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp. to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus, and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments.

  14. Biosurfactants in agriculture.

    Science.gov (United States)

    Sachdev, Dhara P; Cameotra, Swaranjit S

    2013-02-01

    Agricultural productivity to meet growing demands of human population is a matter of great concern for all countries. Use of green compounds to achieve the sustainable agriculture is the present necessity. This review highlights the enormous use of harsh surfactants in agricultural soil and agrochemical industries. Biosurfactants which are reported to be produced by bacteria, yeasts, and fungi can serve as green surfactants. Biosurfactants are considered to be less toxic and eco-friendly and thus several types of biosurfactants have the potential to be commercially produced for extensive applications in pharmaceutical, cosmetics, and food industries. The biosurfactants synthesized by environmental isolates also has promising role in the agricultural industry. Many rhizosphere and plant associated microbes produce biosurfactant; these biomolecules play vital role in motility, signaling, and biofilm formation, indicating that biosurfactant governs plant-microbe interaction. In agriculture, biosurfactants can be used for plant pathogen elimination and for increasing the bioavailability of nutrient for beneficial plant associated microbes. Biosurfactants can widely be applied for improving the agricultural soil quality by soil remediation. These biomolecules can replace the harsh surfactant presently being used in million dollar pesticide industries. Thus, exploring biosurfactants from environmental isolates for investigating their potential role in plant growth promotion and other related agricultural applications warrants details research. Conventional methods are followed for screening the microbial population for production of biosurfactant. However, molecular methods are fewer in reaching biosurfactants from diverse microbial population and there is need to explore novel biosurfactant from uncultured microbes in soil biosphere by using advanced methodologies like functional metagenomics.

  15. Biosurfactants in agriculture.

    Science.gov (United States)

    Sachdev, Dhara P; Cameotra, Swaranjit S

    2013-02-01

    Agricultural productivity to meet growing demands of human population is a matter of great concern for all countries. Use of green compounds to achieve the sustainable agriculture is the present necessity. This review highlights the enormous use of harsh surfactants in agricultural soil and agrochemical industries. Biosurfactants which are reported to be produced by bacteria, yeasts, and fungi can serve as green surfactants. Biosurfactants are considered to be less toxic and eco-friendly and thus several types of biosurfactants have the potential to be commercially produced for extensive applications in pharmaceutical, cosmetics, and food industries. The biosurfactants synthesized by environmental isolates also has promising role in the agricultural industry. Many rhizosphere and plant associated microbes produce biosurfactant; these biomolecules play vital role in motility, signaling, and biofilm formation, indicating that biosurfactant governs plant-microbe interaction. In agriculture, biosurfactants can be used for plant pathogen elimination and for increasing the bioavailability of nutrient for beneficial plant associated microbes. Biosurfactants can widely be applied for improving the agricultural soil quality by soil remediation. These biomolecules can replace the harsh surfactant presently being used in million dollar pesticide industries. Thus, exploring biosurfactants from environmental isolates for investigating their potential role in plant growth promotion and other related agricultural applications warrants details research. Conventional methods are followed for screening the microbial population for production of biosurfactant. However, molecular methods are fewer in reaching biosurfactants from diverse microbial population and there is need to explore novel biosurfactant from uncultured microbes in soil biosphere by using advanced methodologies like functional metagenomics. PMID:23280539

  16. Carbon, Nitrogen and Phosphorus Accumulation and Partitioning, and C:N:P Stoichiometry in Late-Season Rice under Different Water and Nitrogen Managements

    OpenAIRE

    Yushi Ye; Xinqiang Liang; Yingxu Chen; Liang Li; Yuanjing Ji; Chunyan Zhu

    2014-01-01

    Water and nitrogen availability plays an important role in the biogeochemical cycles of essential elements, such as carbon (C), nitrogen (N) and phosphorus (P), in agricultural ecosystems. In this study, we investigated the seasonal changes of C, N and P concentrations, accumulation, partitioning, and C:N:P stoichiometric ratios in different plant tissues (root, stem-leaf, and panicle) of late-season rice under two irrigation regimes (continuous flooding, CF; alternate wetting and drying, AWD...

  17. Phosphorus and Sediment Yield Characterization In Catchments (psychic)

    Science.gov (United States)

    Withers, P. J. A.; Quinton, J. N.; Heathwaite, A. L.; Johnes, P. J.; Walling, D. E.; Jarvie, H. P.

    Policy, regulatory and conservation bodies in the UK have identified an urgent need for a pragmatic decision support system that will allow measures to control agricultural loads of particulates and phosphorus (P) to be implemented in a strategic way within priority river basins suffering the effects of diffuse pollution. Using current scientific understanding and available information, together with a cost-conscious water qual- ity monitoring and sampling programme, research is underway to develop a decision support system to locate specific source areas of particulate and P loss in two study basins, identify practical and cost-effective options to control the loss in these areas, and evaluate the nature and scale of any barriers to uptake. In addition, the project seeks to identify the data requirements and costs needed to operate such a decision support system, the scale at which the data is required together with the ease and cost of accessing the data. A two-stage approach has been adopted which includes an initial identification of high-risk areas in each basin using risk assessment methodology and 1 km2 datasets, followed by a finer scale (field/farm) assessment of specific source areas of particulate and P loss within the high risk areas, and their export rates. Cost- effective control practices will be informed by process-based modelling approaches which are able to quantify the impact of changes in P inputs and land management on P export rates. The experiences, drawbacks and challenges of developing such a decision support system are described in the context of the requirements of the EC Water Framework Directive.

  18. Drivers of Phosphorus Uptake by Barley Following Secondary Resource Application.

    Science.gov (United States)

    Brod, Eva; Øgaard, Anne Falk; Krogstad, Tore; Haraldsen, Trond Knapp; Frossard, Emmanuel; Oberson, Astrid

    2016-01-01

    Minable rock phosphate is a finite resource. Replacing mineral phosphorus (P) fertilizer with P-rich secondary resources is one way to manage P more efficiently, but the importance of physicochemical and microbial soil processes induced by secondary resources for plant P uptake is still poorly understood. Using radioactive-labeling techniques, the fertilization effects of dairy manure, fish sludge, meat bone meal, and wood ash were studied as P uptake by barley after 44 days and compared with those of water-soluble mineral P (MinP) and an unfertilized control (NoP) in a pot experiment with an agricultural soil containing little available P at two soil pH levels, approximately pH 5.3 (unlimed soil) and pH 6.2 (limed soil). In a parallel incubation experiment, the effects of the secondary resources on physicochemical and microbial soil processes were studied. The results showed that the relative agronomic efficiency compared with MinP decreased in the order: manure ≥fish sludge ≥wood ash ≥meat bone meal. The solubility of inorganic P in secondary resources was the main driver for P uptake by barley (Hordeum vulgare). The effects of secondary resources on physicochemical and microbial soil processes were of little overall importance. Application of organic carbon with manure resulted in microbial P immobilization and decreased uptake by barley of P derived from the soil. On both soils, P uptake by barley was best explained by a positive linear relationship with the H2O + NaHCO3-soluble inorganic P fraction in fertilizers or by a linear negative relationship with the HCl-soluble inorganic P fraction in fertilizers. PMID:27243015

  19. Drivers of phosphorus uptake by barley following secondary resource application

    Directory of Open Access Journals (Sweden)

    Eva eBrod

    2016-05-01

    Full Text Available Minable rock phosphate is a finite resource. Replacing mineral phosphorus (P fertilizer with P-rich secondary resources is one way to manage P more efficiently, but the importance of physicochemical and microbial soil processes induced by secondary resources for plant P uptake are still poorly understood. Using radioactive labelling techniques, the fertilization effects of dairy manure, fish sludge, meat bone meal and wood ash were studied as P uptake by barley after 44 days and compared with those of water-soluble mineral P (MinP and an unfertilized control (NoP in a pot experiment with an agricultural soil containing little available P at two soil pH levels, approximately pH 5.3 (unlimed soil and pH 6.2 (limed soil. In a parallel incubation experiment, the effects of the secondary resources on physicochemical and microbial soil processes were studied. The results showed that the relative agronomic efficiency compared with MinP decreased in the order: manure ≥ fish sludge ≥ wood ash ≥ meat bone meal. The solubility of inorganic P in secondary resources was the main driver for P uptake by barley (Hordeum vulgare. The effects of secondary resources on physicochemical and microbial soil processes were of little overall importance. Application of organic carbon with manure resulted in microbial P immobilisation and decreased uptake by barley of P derived from the soil. On both soils, P uptake by barley was best explained by a positive linear relationship with the H2O + NaHCO3-soluble inorganic P fraction in fertilizers, or by a linear negative relationship with the HCl-soluble inorganic P fraction in fertilizers.

  20. Phosphorus contents and availability of technogenic substrates for soil construction

    Science.gov (United States)

    Nehls, Thomas; Lydia, Paetsch; Sarah, Rokia; Schwartz, Christophe; Wessolek, Gerd

    2014-05-01

    Urban areas lack of green and of soil substrates to support this green. A great variety of solid waste materials can be seen as technogenic substances (TS) for the construction of soil-similar plant substrates. Biomass production in the city and the use of waste materials as nutrient sources can help to close regional nutrient cycles. The most important waste materials have been studied for their phosphorus contents, availabilities and diffusion rates in the rhizosphere by combining their analyzed chemical and physical properties. Compost, concrete, green wastes, paper mill sludge, street-sweepings, mix of rubble, bricks, track ballasts and charcoal have (i) been analyzed their P release properties (HF extraction, Olsen-P, adsorption isotherms); (ii) the physical properties (water retention function, saturated hydraulic conductivity) were analyzed at 80 % of the proctor density; (iii) The P availability of the TMs to the roots were simulated for different pressure heads (pF = 1.3, 1.8 and 3.0) using HYDRUS 1-D. We compared the results for TS with these for agricultural soils. Ptot varies from 710 to 21 000 mg kg-1 for bricks and compost, while POlsen varies from 19 to 1 090 mg kg-1 for charcoal and green wastes. The diffusion rates of TSs (pF = 1.3) are up to 10 times higher compared to those of soils, with green wastes showing highest and bricks the lowest P diffusion rates. We conclude that the investigated TS are appropriate for construction of soil similar planting substrates because of their P delivery potential and their favourable physical properties.

  1. [Effects of agricultural activities and transgenic crops on agricultural biodiversity].

    Science.gov (United States)

    Zhang, Xi-Tao; Luo, Hong-Bing; Li, Jun-Sheng; Huang, Hai; Liu, Yong-Bo

    2014-09-01

    Agricultural biodiversity is a key part of the ecosystem biodiversity, but it receives little concern. The monoculture, environmental pollution and habitat fragmentation caused by agricultural activities have threatened agricultural biodiversity over the past 50 years. To optimize agricultural management measures for crop production and environmental protection, we reviewed the effects of agricultural activities, including cultivation patterns, plastic mulching, chemical additions and the cultivation of transgenic crops, on agricultural biodiversity. The results showed that chemical pesticides and fertilizers had the most serious influence and the effects of transgenic crops varied with other factors like the specific transgene inserted in crops. The environmental risk of transgenic crops should be assessed widely through case-by-case methods, particularly its potential impacts on agricultural biodiversity. It is important to consider the protection of agricultural biodiversity before taking certain agricultural practices, which could improve agricultural production and simultaneously reduce the environmental impacts.

  2. Recent Advances in Modeling Phosphorus and Nitrogen Delivery to the Gulf of Mexico and Implications for Managing Nutrients n the Mississippi River Basin

    Science.gov (United States)

    Alexander, R. B.; Smith, R. A.; Schwarz, G. E.; Boyer, E. W.; Nolan, J. V.; Brakebill, J. W.

    2008-12-01

    Although the increased availability of reactive nutrients in past decades has benefited society via food and energy production, the corresponding rise in nutrient loadings to aquatic ecosystems is of particular concern, especially in many estuaries globally where increased nutrient loads have contributed to eutrophic conditions. In the United States, elevated riverine nutrients have contributed to stressed trophic conditions in a majority of estuaries, including the shallow coastal waters of the Louisiana shelf in the northern Gulf of Mexico, where both nitrogen and phosphorus loadings are recognized as contributing to seasonal hypoxic conditions. Advances in geospatial modeling of nitrogen and phosphorus sources and transport in the Mississippi and Atchafalaya River Basins (MARB), as reported in a recent U.S. Geological Survey (USGS) study, provide important information to support improved assessments and management of nutrient loadings to the northern Gulf of Mexico. We summarize the findings of this study and discuss the implications for managing nutrient sources in the MARB. The study reveals important differences in the sources and aquatic transport of nitrogen and phosphorus that affect delivery to the Gulf. Although agricultural sources contribute a majority of the delivered nutrients to the Gulf, corn and soybean cultivation is the largest contributor of nitrogen whereas phosphorus originates primarily from animal manure on pasture and rangelands. Atmospheric deposition is the second leading source of nitrogen, with urban sources contributing relatively small quantities of both nutrients. Furthermore, we find that both nitrogen and phosphorus delivery to the Gulf is controlled by hydrological and biogeochemical processes (e.g., water travel time, denitrification, storage) that scale with stream size, although phosphorus also displays large local- and regional-scale differences in delivery caused by reservoir trapping. The importance of these processes

  3. The cultivated agricultural environment

    International Nuclear Information System (INIS)

    Local agricultural practices in the Nordic countries have resulted in a great diversity in agriculture in the Nordic countries. The diversities mean that in the event of contamination of agricultural land by radioactive fallout the consequences may differ greatly from region to region. For crops and soils contaminated directly by radioactive fallout there are five primary causes for concern, namely: 1. short-term internal contamination of man and animals through ingestion of surface-contaminated mature crops; 2. internal contamination of crops through foliar intake; 3. contamination of mature crops from resuspended soil; 4. direct irradiation of agricultural workers; 5. internal irradiation from inhalation of resuspended soil particulates. In the short-term, most of the radionuclides likely to be released to the atmosphere in the event of an accident have a potential to cause problems in agriculture and many have the potential for causing long-term problems. Generally, the magnitude of the problems created will depend on the: deposition mechanism (wet or dry); radionuclide composition of the fallout; type of farming system (i.e. arable or dairy); type of soil (for instance organic soils are more sensitive than mineral soils with respect to radiocaesium); state of development of the crop which in turn is determined by the season of the year. (EG)

  4. Agricultural land evaluation in the process of agricultural land consolidation

    OpenAIRE

    Fištravec, Polonca

    2008-01-01

    Agricultural land is limited and therefore needs to be protected, preserved and adequately managed. One of the most important instruments of rural planning as well as agricultural land planning represent agricultural operations, first of all the process of land consolidation. Diploma thesis deals with the process of agricultural land consolidation as a whole, emphasizing the agricultural land evaluation during the process. This is cruicial for just and efficient dealings of the...

  5. Biogas - agriculture and environment

    Energy Technology Data Exchange (ETDEWEB)

    Knudsen, L.; Birkmose, T. [The Danish Agricultural Advisory Centre, Aarhus (Denmark)

    1997-08-01

    Cultivating the soil always leads to a higher loss of nutrients to the surrounding environment than the loss recorded from natural areas. Loss of nitrogen by leaching may have the effect that the set limit for nitrate of 50 mg NO{sub 3} per litre of water is exceeded in areas, where the water supply is based on ground water. Furthermore, nitrogen leaching may lead to eutrophication followed by oxygen depletion in inland waterways whereas it has hardly any significant environmental impact in freshwater areas. Ammonia volatilization followed by deposition influences nutrient-poor bio-topes like heaths, marshland etc. Increasing importance is attached to the loss of phosphorus from farmland as the discharge of sewage from urban areas and industries are reduced due to effective chemical and biological treatment plants. Environmental problems related to loss phosphorus is primarily eutrophication of freon water lakes. Nitrous oxide(N{sub 2}O), resulting from denitrification of nitrate in the soil, and the emission of methane contribute considerably to the greenhouse effect. Both nitrous oxide and the emission of methane are influenced by the volume of animal production, but no certain data on the connection and the importance are available. Loss of nutrients from farm production is primarily related to animal production. The largest environmental impact concerns the loss of nutrients in areas, where the live-stock production is very intensive in large compact areas and, where the produced amount of nutrients in animal manure and other organic manures exceed the requirements of the crops. (EG) 13 refs.

  6. Data mining in agriculture

    CERN Document Server

    Mucherino, Antonio; Pardalos, Panos M

    2009-01-01

    Data Mining in Agriculture represents a comprehensive effort to provide graduate students and researchers with an analytical text on data mining techniques applied to agriculture and environmental related fields. This book presents both theoretical and practical insights with a focus on presenting the context of each data mining technique rather intuitively with ample concrete examples represented graphically and with algorithms written in MATLAB®. Examples and exercises with solutions are provided at the end of each chapter to facilitate the comprehension of the material. For each data mining technique described in the book variants and improvements of the basic algorithm are also given. Also by P.J. Papajorgji and P.M. Pardalos: Advances in Modeling Agricultural Systems, 'Springer Optimization and its Applications' vol. 25, ©2009.

  7. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    The measurement issue is the key issue in the literature on trade policy-induced agri-cultural price incentive bias. This paper introduces a general equilibrium effective rate of protection (GE-ERP) measure, which extends and generalizes earlier partial equilibrium nominal protection measures....... For the 15 sample countries, the results indicate that the agricultural price incentive bias, which was generally perceived to exist during the 1980s, was largely eliminated during the 1990s. The results also demonstrate that general equilibrium effects and country-specific characteristics - including trade...... shares and intersectoral linkages - are crucial for determining the sign and magnitude of trade policy bias. The GE-ERP measure is therefore uniquely suited to capture the full impact of trade policies on agricultural price incentives. A Monte Carlo procedure confirms that the results are robust...

  8. AGRICULTURAL ECONOMICS, INTERDEPENDENCE AND UNCERTAINTY

    OpenAIRE

    Anderson, Jock R.

    1982-01-01

    Interdependence has always been central to economics but assumes pressing importance for agricultural economists as they deal with industrialising agricultures. Continued unresolvable uncertainties, when properly recognised, also add to the challenge of relevant work in agricultural economics. The related roles of interdependence and uncertainty are illustrated through examples from the progress of agricultural technology and enhancement of food security.

  9. Rapid transport and transformation of phosphorus species during the leaching of poultry manure amended soil

    Science.gov (United States)

    Giles, Courtney; Cade-Menun, Barbara; Liu, Corey; Hill, Jane

    2015-04-01

    The loss of phosphorus (P) from soils due to leaching is a major concern in heavily fertilized agricultural regions. The mobility and transformation of P species will depend on the source of manure fertilizer, leaching regime, and the extent of soil P saturation within the soil profile. We investigate spatial and temporal changes in the distribution of P species within a poultry manure-amended soil at two depths (0-5, 10-15 cm) as well as leachate P fractions during 10 weeks of leaching. Leachate P was primarily composed of dissolved fractions (soluble reactive P; dissolved unreactive P) and reached a maximum in the fourth week of leaching. In soils, the degree of P saturation (80%) and water extractable P (9 mg kg-1) were also greatest in week 4. 31P NMR spectra of the 0-5 cm depth indicate that surface soils were most similar to the poultry manure in week 4. During peak leaching, the proportion of orthophosphate (OrthoP) at the soil surface (0-5 cm; 80%) was greater than that from the lowest depth (10-15 cm; 72%), which contained relatively larger proportions of monoester-(17%) and diester-P classes (10%). Poultry manure likely contributed to the mobile pool of P species, including OrthoP, myo-inositol hexakisphosphate (myo-IHP), and nucleic acids. The appearance of neo- and D-chiro-IHP, as well as phospholipid signals during the leaching period indicate possible short-term (organic P to the generation and leaching of OrthoP, under P-saturated conditions. Further work is needed to determine how fertilization and leaching will affect the mobility and transformation of P species across a wider range of soil types. Keywords: Phytate, organic phosphorus, degree of phosphorus saturation, soil, leachate, poultry manure

  10. Growth and accumulation of phosphorus by bean plants treated with foliar phosphate and phosphite

    Directory of Open Access Journals (Sweden)

    Josinaldo Lopes Araujo

    2014-09-01

    Full Text Available Currently the use of phosphite as fungicide in agriculture or as a supplementary source of phosphorus (P has been widespread, however little is known about its effects on phosphate nutrition of important crops such as bean plants. The present work aimed to evaluate the effect of foliar applied phosphite and phosphate on the growth and phosphated nutrition of the bean plant cultivated under low and adequate P supply conditions. The experiment was conducted in an entirely random layout, in factorial scheme 2 x 3 x 2, where two phosphate concentrations were combined in the nutrient solution (1.5 mg L-1 = low phosphorous and 20 mg L-1 = adequate phosphorous, three foliar application products: KH2PO3 (monobasic potassium phosphite, KH2PO4 (monobasic potassium phosphate and KCl (potassium chloride as control and two treatments referring to the number of applications (one application, at the appearance of the first trifoliolate leaf and two applications: one at the appearance of the first trifoliolate leaf and the other application at the pre-flowering, with four repetitions. Overall the dry matter, fosfatase activity, phosphorus content and phosphorus use efficiency was not were affected by the foliar application treatments. Under low readiness of that nutritient the application of foliar phosphite had a negative effect on these variables. It was concluded that foliar applied phosphite has a depressive effect on the growth of the bean plant under low supply of P. The foliar phosphite slightly affects the total concentration of P in the roots and shoots, especially under low P supply, and provides no changes in levels of soluble fractions of P in leaves under conditions of low or adequate supply this nutrient.

  11. Enhanced Biological Phosphorus Removal from Dairy Manure to Meet Nitrogen:Phosphorus Crop Nutrient Requirements

    OpenAIRE

    Yanosek, Kristina Anne

    2002-01-01

    Over the last two decades, livestock operations have become highly concentrated due to growing trends towards larger, more confined facilities and a decrease in cropland on smaller farms. This has led to greater amounts of excess manure nutrients on farms, increasing the potential for nutrient pollution of water bodies from runoff. The purpose of this study was to determine if enhanced biological phosphorus removal (EBPR) is a viable alternative for managing excess manure nutrients on dairy...

  12. Preliminary analysis of phosphorus flow in Hue Citadel.

    Science.gov (United States)

    Anh, T N Q; Harada, H; Fujii, S; Anh, P N; Lieu, P K; Tanaka, S

    2016-01-01

    Characteristics of waste and wastewater management can affect material flows. Our research investigates the management of waste and wastewater in urban areas of developing countries and its effects on phosphorus flow based on a case study in Hue Citadel, Hue, Vietnam. One hundred households were interviewed to gain insight into domestic waste and wastewater management together with secondary data collection. Next, a phosphorus flow model was developed to quantify the phosphorus input and output in the area. The results showed that almost all wastewater generated in Hue Citadel was eventually discharged into water bodies and to the ground/groundwater. This led to most of the phosphorus output flowing into water bodies (41.2 kg P/(ha year)) and ground/groundwater (25.3 kg P/(ha year)). Sewage from the sewer system was the largest source of phosphorus loading into water bodies, while effluent from on-site sanitation systems was responsible for a major portion of phosphorus into the ground/groundwater. This elevated phosphorus loading is a serious issue in considering surface water and groundwater protection. PMID:26744936

  13. Relative Contributions of Phosphorus in High Elevation Sierra Nevada Lakes

    Science.gov (United States)

    Jensen, L. K.; McIntyre, B. M.; Lyons, R. A.

    2015-12-01

    High elevation lakes of the Sierra Nevada mountain range show signs of eutrophication due to increased phosphorus loading. Phosphorus is a major contributing factor to freshwater lake eutrophication when in excess. Three previously researched sources of phosphorus to high-elevation montane lakes include atmospheric deposition, internal loading from sediments, and excretions from non-native stocked fish. The goal of this research was to isolate the estimated phosphorus contributions from residential shoreline developments and stocked non-native fish. A steady-state phosphorus loading rate model was created to quantify relative phosphorus loading into two lakes in the Eastern Sierra Nevada: Convict and Silver Lake. A conglomerate control lake was created from Eastern Brook Lake in the Eastern Sierra Nevada, Pear Lake in the Southern Sierra Nevada, and Snowflake Lake in Canada. Both Convict and Silver Lakes contain stocked non-native trout species and Silver Lake also has ~25 vacation homes on its eastern shore. Seasonal steady-state total phosphorus concentrations were determined using EPA Method 365.2. Loading rate constants were calculated using loading rates from literature and corresponding concentrations. It was determined that as much as 42% of phosphorous to Silver Lake came from shoreline housing developments, and 24% came from stocked fish depending on the season. Previous studies showed much lower contributions from non-native fish.

  14. Preliminary analysis of phosphorus flow in Hue Citadel.

    Science.gov (United States)

    Anh, T N Q; Harada, H; Fujii, S; Anh, P N; Lieu, P K; Tanaka, S

    2016-01-01

    Characteristics of waste and wastewater management can affect material flows. Our research investigates the management of waste and wastewater in urban areas of developing countries and its effects on phosphorus flow based on a case study in Hue Citadel, Hue, Vietnam. One hundred households were interviewed to gain insight into domestic waste and wastewater management together with secondary data collection. Next, a phosphorus flow model was developed to quantify the phosphorus input and output in the area. The results showed that almost all wastewater generated in Hue Citadel was eventually discharged into water bodies and to the ground/groundwater. This led to most of the phosphorus output flowing into water bodies (41.2 kg P/(ha year)) and ground/groundwater (25.3 kg P/(ha year)). Sewage from the sewer system was the largest source of phosphorus loading into water bodies, while effluent from on-site sanitation systems was responsible for a major portion of phosphorus into the ground/groundwater. This elevated phosphorus loading is a serious issue in considering surface water and groundwater protection.

  15. Black phosphorus saturable absorber for ultrashort pulse generation

    International Nuclear Information System (INIS)

    Low-dimensional materials, due to their unique and versatile properties, are very interesting for numerous applications in electronics and optoelectronics. Recently rediscovered black phosphorus, with a graphite-like layered structure, can be effectively exfoliated up to the single atomic layer called phosphorene. Contrary to graphene, it possesses a direct band gap controllable by the number of stacked atomic layers. For those reasons, black phosphorus is now intensively investigated and can complement or replace graphene in various photonics and electronics applications. Here, we demonstrate that black phosphorus can serve as a broadband saturable absorber and can be used for ultrashort optical pulse generation. The mechanically exfoliated ∼300 nm thick layers of black phosphorus were transferred onto the fiber core, and under pulsed excitation at 1560 nm wavelength, its transmission increases by 4.6%. We have demonstrated that the saturable absorption of black phosphorus is polarization sensitive. The fabricated device was used to mode-lock an Er-doped fiber laser. The generated optical solitons with the 10.2 nm bandwidth and 272 fs duration were centered at 1550 nm. The obtained results unambiguously show that black phosphorus can be effectively used for ultrashort pulse generation with performances similar or even better than currently used graphene or carbon nanotubes. This application of black phosphorus proves its great potential to future practical use in photonics

  16. Dietary phosphorus requirement of young abalone Haliotis discus Hannai Ino

    Science.gov (United States)

    Tan, Bei-Ping; Mai, Kang-Sen; Liufu, Zhi-Guo

    2002-03-01

    An experiment was performed to determine the dietary phosphorus requirement of the young abalone, Haliotis discus hannai. Five semi-purified diets were formulated to provide a series of graded levels of dietary total phosphorus (0.23% 1.98) from monobasic potassium phosphate (KH2P04). The brown alga, Laminaria japonica, was used as a control diet. Similar size abalone were distributed in a single-pass, flow-through system using a completely randomized design with six treatments and three replicates each treatment. The abalone were hand-fed to satiation with appropriate diets in excess, once daily at 17:00. The feeding trial was run for 120-d. Survival rate and soft-body to shell ratio (SB/S) were constantly maintained regardless of dietary treatment. However, the weight gain rate (WGR), daily increment in shell length (DISL), muscle RNA to DNA ratio (RNA/DNA), carcass levels of lipid and protein, soft-body alkaline phosphatase (SBAKP), and phosphorus concentrations of whole body (WB) and soft body (SB) were significantly (ANOVA, P<0.05) affected by the dietary phosphorus level. The dietary phosphorus requirements of the abalone were evaluated from the WGR, DISL, and RNA/DNA ratio respectively, by using second-order polynomial regression analysis. Based on these criteria, about 1.0% 1.2% total dietary phosphorus, i.e. 0.9% 1.1% dietary available phosphorus is recommended for the maximum growth of the abalone.

  17. Black phosphorus saturable absorber for ultrashort pulse generation

    Energy Technology Data Exchange (ETDEWEB)

    Sotor, J., E-mail: jaroslaw.sotor@pwr.edu.pl; Sobon, G.; Abramski, K. M. [Laser and Fiber Electronics Group, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370 (Poland); Macherzynski, W.; Paletko, P. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, Wroclaw 50-372 (Poland)

    2015-08-03

    Low-dimensional materials, due to their unique and versatile properties, are very interesting for numerous applications in electronics and optoelectronics. Recently rediscovered black phosphorus, with a graphite-like layered structure, can be effectively exfoliated up to the single atomic layer called phosphorene. Contrary to graphene, it possesses a direct band gap controllable by the number of stacked atomic layers. For those reasons, black phosphorus is now intensively investigated and can complement or replace graphene in various photonics and electronics applications. Here, we demonstrate that black phosphorus can serve as a broadband saturable absorber and can be used for ultrashort optical pulse generation. The mechanically exfoliated ∼300 nm thick layers of black phosphorus were transferred onto the fiber core, and under pulsed excitation at 1560 nm wavelength, its transmission increases by 4.6%. We have demonstrated that the saturable absorption of black phosphorus is polarization sensitive. The fabricated device was used to mode-lock an Er-doped fiber laser. The generated optical solitons with the 10.2 nm bandwidth and 272 fs duration were centered at 1550 nm. The obtained results unambiguously show that black phosphorus can be effectively used for ultrashort pulse generation with performances similar or even better than currently used graphene or carbon nanotubes. This application of black phosphorus proves its great potential to future practical use in photonics.

  18. A Novel Approach to Bioleach Soluble Phosphorus from Rock Phosphate

    Institute of Scientific and Technical Information of China (English)

    池汝安; 肖春桥; 黄晓慧; 王存文; 吴元欣

    2007-01-01

    A novel approach to bioleach soluble phosphorus from rock phosphate, involving the bio-oxidation of pyrite by adaptated Acidithiobacillus ferrooxidans (At. f) and the product of sulfuric acid to dissolve rock phosphate, has been proposed in this paper. The soluble phosphorus could be leached more effectively in the presence of pyrite by At. f than that leached directly by sulfuric acid. The optimal technological parameters are presented. The highest phosphorus leaching rate is 9.00% when the culture substrate is the mixture of FeSO4·7H2O and pyrite, the phosphorus leaching rate is 8.00% when the initial pH and culture time are 2.5 and 5 d, respectively. The optimal rock phosphate particle size is 0.05 mm for the leaching of phosphorus. The bigger the grains of pyrite, the lower the phosphorus leaching rate. The bacterium At. f should be appropriately adaptated, which makes it easier to bioleach soluble phosphorus from rock phosphate.

  19. A substance flow analysis of phosphorus in the food production, processing and consumption system of the Netherlands

    OpenAIRE

    Smit, A.L.; Middelkoop, van, J.C.; van Dijk; Reuler, van, H.

    2015-01-01

    Phosphorus (P) is an essential nutrient in agriculture. In recent years 15–18 Mt of P was used as mineral fertilizer in the global food production chain. The major source of this fertilizer is phosphate rock which is unfortunately a finite resource. In the long term this necessitates efficient use of fertilizer and optimized recycling of P rich waste streams (including manure). In order to determine the potential for sustainable use of P we performed a 3-year substance flow analysis (SFA) for...

  20. Overexpression of a Gene Involved in Phytic Acid Biosynthesis Substantially Increases Phytic Acid and Total Phosphorus in Rice Seeds

    OpenAIRE

    Yusuke Tagashira; Tomoe Shimizu; Masanobu Miyamoto; Sho Nishida; Yoshida, Kaoru T.

    2015-01-01

    The manipulation of seed phosphorus is important for seedling growth and environmental P sustainability in agriculture. The mechanism of regulating P content in seed, however, is poorly understood. To study regulation of total P, we focused on phytic acid (inositol hexakisphosphate; InsP6) biosynthesis-related genes, as InsP6 is a major storage form of P in seeds. The rice (Oryza sativa L.) low phytic acid mutant lpa1-1 has been identified as a homolog of archael 2-phosphoglycerate kinase. Th...

  1. Agricultural risk management

    DEFF Research Database (Denmark)

    Lund, Mogens; Oksen, Arne; Larsen, Torben U.;

    2005-01-01

    A new model for risk management in agriculture is described in the paper. The risk model is constructed as a context dependent process, which includes four main phases. The model is aimed at agricultural advisors, who wish to facilitate and disseminate risk management to farmers. It is developed...... and tested by an action research approach in an attempt to make risk management more applicable on family farms. Our obtained experiences indicate that farmers don’t apply probabilistic thinking and other concepts according to formal decision theory....

  2. COMPARISON OF SOIL TEST METHODS FOR AVAILABLE PHOSPHORUS IN COMMON CALCAREOUS BLACK SOIL

    Directory of Open Access Journals (Sweden)

    Biryukova O. A.

    2014-11-01

    Full Text Available The article presents a comparative analysis of the results on available phosphorus measurements in common black soils using the Machigin and Olsen methods. The relationships between maize productivity and soil available phosphorus and also between phosphorus concentrations in the above-ground plant parts and soil available phosphorus were identified at various stages of crop development

  3. COMPARISON OF SOIL TEST METHODS FOR AVAILABLE PHOSPHORUS IN COMMON CALCAREOUS BLACK SOIL

    OpenAIRE

    Biryukova O. A.; Bozhkov D. V.; Nosov V. V.

    2014-01-01

    The article presents a comparative analysis of the results on available phosphorus measurements in common black soils using the Machigin and Olsen methods. The relationships between maize productivity and soil available phosphorus and also between phosphorus concentrations in the above-ground plant parts and soil available phosphorus were identified at various stages of crop development

  4. A GAO hiding among the PAO: The role of the Propionivibrio spp. in biological phosphorus removal

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Albertsen, Mads; Stokholm-Bjerregaard, Mikkel;

    Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater...

  5. Impact of fertilizer phosphorus application on phosphorus release kinetics in some calcareous soils

    Science.gov (United States)

    Hosseinpur, A. R.; Biabanaki, F. S.

    2009-01-01

    Phosphate reactions and retention in the soil are of paramount importance from the perspective of plant nutrition and fertilizer use efficiency. The objective of this work was to study the kinetics of phosphorus (P) desorption in different soils of Hamadan in fertilized and unfertilized soils. Soils were fertilized with 200 mg P kg-1. Fertilized and unfertilized soils were incubated at 25 ± 1°C for 6 months. After that, release of P was studied by successive extraction with 0.5 M NaHCO3 over a period of 1,752 h. The results showed that phosphorus desorption from the fertilized and unfertilized soils began with a fast initial reaction, followed by a slow secondary reaction. The amount of P released after 1,752 h in fertilized and unfertilized soils ranged from 457 to 762.4 and 309.6 to 586.7 mg kg-1, respectively. The kinetics of cumulative P release was evaluated using the five kinetic equations. Phosphorus desorption kinetics were best described by parabolic diffusion law, first order, and power function equations. Rate constants of these equations were higher in fertilized than unfertilized soils. Results from this study indicate that release rate of P plays a significant role in supplying available P and released P in runoff.

  6. Mass transfer of phosphorus in high-phosphorus hot-metal refining

    Institute of Scientific and Technical Information of China (English)

    Jiang Diao; Xuan Liu,; Tao Zhang; Bing Xie

    2015-01-01

    Mass transfer of phosphorus in high-phosphorus hot-metal refining was investigated using CaO−FetO−SiO2 slags at 1623 K. Based on a two-film theory kinetic model and experimental results, it was found that the overall mass transfer coefficient, which includes the effects of mass transfer in both the slag phase and metal phase, is in the range of 0.0047 to 0.0240 cm/s. With the addition of a small amount of fluxing agents Al2O3 or Na2O into the slag, the overall mass transfer coefficient has an obvious increase. Silicon content in the hot metal also influences the overall mass transfer coefficient. The overall mass transfer coefficient in the lower [Si] heat is much higher than that in the higher [Si] heat. It is concluded that both fluxing agents and lower [Si] hot metal facilitate mass transfer of phosphorus in liquid phases. Fur-thermore, the addition of Na2O could also prevent rephosphorization at the end of the experiment.

  7. Changing Structure of Turkish Agriculture

    OpenAIRE

    Mann, Charles K.

    1983-01-01

    Professor Resat Aktan, whose memory is honoured by this paper, occupied a unique place in the history of Turkish agriculture--teacher, scholar, Minister of Agriculture, and long-time Turkish delegate to the IAAE. Among his many accomplishments, he led two landmark agricultural surveys which serve to chronicle the development of modern Turkish agriculture. While Ataturk had set Turkey on the road to modernization of agriculture, the end of World War II still found Turkish wheat farming little ...

  8. Strategic analysis of Swedish agriculture

    OpenAIRE

    Fogelfors, Håkan; Wivstad, Maria; Eckersten, Henrik; Holstein, Fredrik; Johansson, Susanne; Verwijst, Theo

    2009-01-01

    This strategic analysis of Swedish agriculture – production systems and agricultural landscapes in a time of change – focuses on climate change, future availability of natural resources and economic regulation in a global food market. The background to the project was that the Faculty of Natural Resources and Agriculture of the Swedish University of Agricultural Sciences identified an urgent need to explore the implications and opportunities of coming changes for agricultural production syste...

  9. Remaining Phosphorus Estimate Through Multiple Regression Analysis

    Institute of Scientific and Technical Information of China (English)

    M. E. ALVES; A. LAVORENTI

    2006-01-01

    The remaining phosphorus (Prem), P concentration that remains in solution after shaking soil with 0.01 mol L-1 CaCl2 containing 60 μg mL-1 P, is a very useful index for studies related to the chemistry of variable charge soils. Although the Prem determination is a simple procedure, the possibility of estimating accurate values of this index from easily and/or routinely determined soil properties can be very useful for practical purposes. The present research evaluated the Premestimation through multiple regression analysis in which routinely determined soil chemical data, soil clay content and soil pH measured in 1 mol L-1 NaF (pHNaF) figured as Prem predictor variables. The Prem can be estimated with acceptable accuracy using the above-mentioned approach, and PHNaF not only substitutes for clay content as a predictor variable but also confers more accuracy to the Prem estimates.

  10. Recovery of gallium from phosphorus industry flue

    Institute of Scientific and Technical Information of China (English)

    许可; 邓彤; 戴玉杰; 王静

    2004-01-01

    The flue dust generated during electric furnace production of elemental phosphorus was investigated for the recovery of gallium. Then the flue dust was slurried with water and blended with concentrated sulfuric acid, followed by ageing. The gallium in the dust was thereby converted to soluble sulfate. The factors affecting the dust curing were investigated to understand the process chemistry of the pretreatment. The optimal curing conditions are determined as follows: the mass ratio of dust to water and acid is 1: 1: 1, ageing temperature and time are 200 ℃ and 2 h, respectively. Almost all the gallium available to acid dissolution in the dust, about 900%00 gallium, can be extracted by leaching the cured dust at 80 ℃ for 1 h.

  11. Phosphorus removal using novel crystallisation technology.

    Science.gov (United States)

    Wood, K; Wood, G; Prokop, D; Lewyille, F

    2006-01-01

    A soy protein manufacturing facility was faced with the challenge of reducing its effluent phosphorus (P) content from 20-50 mg L(-1) down to salt levels to comply with discharge and receiving water requirements. A number of biological and chemical P removal technologies previously evaluated either failed to achieve the new standards or would have produced prohibitive amounts of residual sludge and unacceptably high effluent salt concentrations. Lime precipitation, utilising a novel crystallisation technology, was demonstrated through on-site pilot testing to meet the process objectives. It is capable of achieving the required P removal at pH 10 while not increasing soluble salts and producing rapid settling and filterable particles. Also, minimal carbonate removal was observed with residual solids generation being only 40% of a complete lime softening reaction. This paper describes the technical evaluation that led to the full-scale treatment system that was put into operation in late 2005. PMID:16889253

  12. Organic Phosphorus in the Deep Subseafloor Environment

    Science.gov (United States)

    Defforey, D.; Paytan, A.

    2014-12-01

    Phosphorus (P) is a macronutrient involved both in functional and structural components of all living cells. This makes it an essential nutrient for life, including microbial life in the deep subseafloor habitat. P availability in this environment is limited since organic matter is scarce and P is thought to be mainly present in refractory mineral phases. However, recent estimates suggest that the deep biosphere may contain up to 1% of Earth's total biomass, which implies that microorganisms may possess mechanisms to harvest recalcitrant phosphorus compounds in this environment. In addition, the role of the organic P pool in this setting is poorly understood and could be of great importance should it represent an important P pool fueling the deep biosphere. This study aims to identify and quantify organic P compounds in open ocean sediments using our newly developed sequential extraction procedure for 31P nuclear magnetic resonance spectroscopy (31P NMR). This method amplifies the signal of organic P in spectra by increasing its concentration and quantitatively removing the majority of inorganic P. Briefly, P bound to iron oxyhydroxides is removed from sediment samples during a reductive step; then, P in authigenic and biogenic apatite is solubilized over the course of an extraction in an acidic buffer. These two steps remove the majority of inorganic P from the sample. Lastly, the residue is extracted in 0.25M NaOH+ 0.05M Na2EDTA and the supernatant is frozen and lyophilized prior to 31P NMR analysis. This method will be applied to sediment samples from North Pond (IODP expedition 336), an isolated sediment pond on the western flank of the Mid-Atlantic ridge. This work will provide valuable insight into the diagenetic processes affecting organic P in open ocean sediments and into possible nutrient sources to the deep biosphere.

  13. Layer Tunable Third-Harmonic Generation in Multilayer Black Phosphorus

    CERN Document Server

    Youngblood, Nathan; Nemilentsau, Andrei; Low, Tony; Li, Mo

    2016-01-01

    Black phosphorus has been the subject of growing interest due to its unique band structure that is both layer dependent and anisotropic. While many have studied the linear optical response of black phosphorus, the nonlinear response has remained relatively unexplored. Here we report on the observation of third-harmonic generation in black phosphorus using an ultrafast near-IR laser and measure chi(3) experimentally for the first time. It was found that chi(3) is highly dependent on both the incident polarization and the number of layers present.

  14. Replace, reuse, recycle: improving the sustainable use of phosphorus by plants.

    Science.gov (United States)

    Baker, Alison; Ceasar, S Antony; Palmer, Antony J; Paterson, Jaimie B; Qi, Wanjun; Muench, Stephen P; Baldwin, Stephen A

    2015-06-01

    The 'phosphorus problem' has recently received strong interest with two distinct strands of importance. The first is that too much phosphorus (P) is entering into waste water, creating a significant economic and ecological problem. Secondly, while agricultural demand for phosphate fertilizer is increasing to maintain crop yields, rock phosphate reserves are rapidly declining. Unravelling the mechanisms by which plants sense, respond to, and acquire phosphate can address both problems, allowing the development of crop plants that are more efficient at acquiring and using limited amounts of phosphate while at the same time improving the potential of plants and other photosynthetic organisms for nutrient recapture and recycling from waste water. In this review, we attempt to synthesize these important but often disparate parts of the debate in a holistic fashion, since solutions to such a complex problem require integrated and multidisciplinary approaches that address both P supply and demand. Rapid progress has been made recently in our understanding of local and systemic signalling mechanisms for phosphate, and of expression and regulation of membrane proteins that take phosphate up from the environment and transport it within the plant. We discuss the current state of understanding of such mechanisms involved in sensing and responding to phosphate stress. We also discuss approaches to improve the P-use efficiency of crop plants and future direction for sustainable use of P, including use of photosynthetic organisms for recapture of P from waste waters. PMID:25944926

  15. 200 years of soil carbon nitrogen and phosphorus change across the United Kingdom

    Science.gov (United States)

    Tipping, Ed; Quinton, John; Davies, Jessica; Bell, Vicky; Carnell, Ed; Dragosits, Ulli; Muhammed, Shibu; Naden, Pam; Stuart, Marianne; Tomlinson, Sam; Whitmore, Andy; Wu, Lianhai

    2015-04-01

    Human intervention over the last 200 years has resulted in vast changes to the fluxes of nitrogen (N) and phosphorus (P) entering the United Kingdom's landscape. Industrialisation has resulted in N deposition, agricultural intensification has seen widespread use of N and P fertilizers and societal actions have resulted in extensive land use change. To understand the consequences of these anthropogenic inputs for our soils, freshwaters and ecosystems it is necessary to take an integrated long term large scale approach. Integration across the compartments of the critical zone - from atmosphere, plants to soil and stream - is necessary in order to trace the effects of deposition, fertilization, cultivation and land use change. Coherent integration of C, N and P dynamics is also crucial, as biological processes tightly couple these cycles, so that in unison C N and P control the generation of biomass and consequent production of soil organic matter, having knock on effects for dissolved and particulate fluxes and ecosystem function. The Long-Term Large-Scale (LTLS) project is developing an integrated model that simulates the pools and fluxes of carbon, nitrogen and phosphorus (C, N, and P) between atmospheric, vegetation, soil and aquatic systems for the whole of the United Kingdom for a period spanning from the onset of the industrial revolution up until the present day. In this paper we will present results demonstrating the changes in the soil macronutrient cycles in response to agrarian and social change in the United Kingdom over the last 200 years

  16. Replace, reuse, recycle: improving the sustainable use of phosphorus by plants.

    Science.gov (United States)

    Baker, Alison; Ceasar, S Antony; Palmer, Antony J; Paterson, Jaimie B; Qi, Wanjun; Muench, Stephen P; Baldwin, Stephen A

    2015-06-01

    The 'phosphorus problem' has recently received strong interest with two distinct strands of importance. The first is that too much phosphorus (P) is entering into waste water, creating a significant economic and ecological problem. Secondly, while agricultural demand for phosphate fertilizer is increasing to maintain crop yields, rock phosphate reserves are rapidly declining. Unravelling the mechanisms by which plants sense, respond to, and acquire phosphate can address both problems, allowing the development of crop plants that are more efficient at acquiring and using limited amounts of phosphate while at the same time improving the potential of plants and other photosynthetic organisms for nutrient recapture and recycling from waste water. In this review, we attempt to synthesize these important but often disparate parts of the debate in a holistic fashion, since solutions to such a complex problem require integrated and multidisciplinary approaches that address both P supply and demand. Rapid progress has been made recently in our understanding of local and systemic signalling mechanisms for phosphate, and of expression and regulation of membrane proteins that take phosphate up from the environment and transport it within the plant. We discuss the current state of understanding of such mechanisms involved in sensing and responding to phosphate stress. We also discuss approaches to improve the P-use efficiency of crop plants and future direction for sustainable use of P, including use of photosynthetic organisms for recapture of P from waste waters.

  17. Present and perspective of enhanced biological phosphorus removal process; Seibutsugakuteki rin jokyoho no genjo to kadai

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K. [National Inst. of Bioscience and Human-Technology, Tsukuba (Japan)

    1997-02-05

    Biological phosphorus removal process utilizing anaerobic and aerobic conditions, mechanism of phosphorus removal, and microbes relating to phosphorus removal are outlined, and future problems are discussed. By mixing waste water and sludge under anaerobic condition followed by treatment under aerobic condition, phosphorus content in sludge increases to enable biological phosphorus removal. More microbes with high polyphosphorus accumulating performance are acquired by the anaerobic/aerobic process than other microbes with the result of their preferential increase, and the process has high phosphorus removal characteristic than the general treatment process. Microbes relating to phosphorus removal, immobilization of polyphosphate accumulating microbes, and phosphorus acquiring and releasing characteristics of immobilized mycelium are discussed. Application of gel entrapped immobilized mycelium to phosphorus removal and problems in biological phosphorus removing methods are described. 18 refs., 12 figs.

  18. Is the Inherent Potential of Maize Roots Efficient for Soil Phosphorus Acquisition?

    Science.gov (United States)

    Deng, Yan; Chen, Keru; Teng, Wan; Zhan, Ai; Tong, Yiping; Feng, Gu; Cui, Zhenling; Zhang, Fusuo; Chen, Xinping

    2014-01-01

    Sustainable agriculture requires improved phosphorus (P) management to reduce the overreliance on P fertilization. Despite intensive research of root adaptive mechanisms for improving P acquisition, the inherent potential of roots for efficient P acquisition remains unfulfilled, especially in intensive agriculture, while current P management generally focuses on agronomic and environmental concerns. Here, we investigated how levels of soil P affect the inherent potential of maize (Zea mays L.) roots to obtain P from soil. Responses of root morphology, arbuscular mycorrhizal colonization, and phosphate transporters were characterized and related to agronomic traits in pot and field experiments with soil P supply from deficiency to excess. Critical soil Olsen-P level for maize growth approximated 3.2 mg kg−1, and the threshold indicating a significant environmental risk was about 15 mg kg−1, which represented the lower and upper levels of soil P recommended in current P management. However, most root adaptations involved with P acquisition were triggered when soil Olsen-P was below 10 mg kg−1, indicating a threshold for maximum root inherent potential. Therefore, to maintain efficient inherent potential of roots for P acquisition, we suggest that the target upper level of soil P in intensive agriculture should be reduced from the environmental risk threshold to the point maximizing the inherent potential of roots. PMID:24594677

  19. Long-term accumulation and transport of anthropogenic phosphorus in world river basins

    Science.gov (United States)

    Powers, S. M.

    2015-12-01

    Global food production crucially depends on phosphorus (P). In agricultural and urban landscapes, much P is anthropogenic, entering via trade, and then can be transported by a combination of fluvial and human processes. To date there have been few long-term, large-scale analyses combining both fluvial and human modes of P transport. Here we present reconstructed historical records of anthropogenic P entering and leaving soils and aquatic systems via a combination of trade, infrastructure, food waste, and fluvial fluxes. We then report the net annual P inputs, and the mass of P that has accumulated over the long-term, for entire river basins. Our analyses reveal rapid historical P accumulation for two mixed agricultural-urban landscapes (Thames Basin, UK, Yangtze Basin, China), and one rural agricultural landscape (Maumee Basin, USA). We also show that the human P fluxes massively dominate over the fluvial fluxes in these large basins. For Thames and Maumee Basins, recently there has been modest P depletion/drawdown of the massive P pool accumulated in prior decades, whereas the Yangtze Basin has consistently and rapidly accumulated P since 1980. These first estimates of the magnitude of historical P accumulation in contrasting settings illustrate the scope of management challenges surrounding the storage, fate, exploitation, and reactivation of legacy P that is currently present in the Earth's critical zone.

  20. Is the inherent potential of maize roots efficient for soil phosphorus acquisition?

    Directory of Open Access Journals (Sweden)

    Yan Deng

    Full Text Available Sustainable agriculture requires improved phosphorus (P management to reduce the overreliance on P fertilization. Despite intensive research of root adaptive mechanisms for improving P acquisition, the inherent potential of roots for efficient P acquisition remains unfulfilled, especially in intensive agriculture, while current P management generally focuses on agronomic and environmental concerns. Here, we investigated how levels of soil P affect the inherent potential of maize (Zea mays L. roots to obtain P from soil. Responses of root morphology, arbuscular mycorrhizal colonization, and phosphate transporters were characterized and related to agronomic traits in pot and field experiments with soil P supply from deficiency to excess. Critical soil Olsen-P level for maize growth approximated 3.2 mg kg(-1, and the threshold indicating a significant environmental risk was about 15 mg kg(-1, which represented the lower and upper levels of soil P recommended in current P management. However, most root adaptations involved with P acquisition were triggered when soil Olsen-P was below 10 mg kg(-1, indicating a threshold for maximum root inherent potential. Therefore, to maintain efficient inherent potential of roots for P acquisition, we suggest that the target upper level of soil P in intensive agriculture should be reduced from the environmental risk threshold to the point maximizing the inherent potential of roots.