Sample records for animal-based agriculture phosphorus

  1. Phosphorus, Agriculture & The Environment

    Mullins, Gregory Lee


    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. Mitigation of phosphorus leaching from agricultural soils

    Svanbäck, Annika


    Phosphorus (P) is an essential element in crop production, but P losses from agricultural soils are a major contributor to surface water eutrophication. This thesis examined the effects of chemical soil properties and soil structure, as governed by agricultural management practices, on P leaching from agricultural soils and how this leaching can be reduced. An initial investigation on the effect of plant-available P concentration in the soil (P-AL) on topsoil P leaching from five soils clearl...

  3. Regulating phosphorus from the agricultural sector

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


      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...... 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...

  4. Phosphorus speciation in Swedish agricultural clay soils

    Eriksson, Ann Kristin


    Phosphorus (P) is an important element for crop production, but build-up of excess soil P can promote P leaching and eutrophication of surface waters. To better understand the dynamics of P release from soil to waters, more knowledge is needed about sorption patterns and P speciation in agricultural soils. Two new indices were developed to assess the importance of P sorption to hydroxy-interlayered clay minerals, and to evaluate the amount of hydroxy-interlayering and hydroxy-interlayer ...

  5. Agricultural trade and the global phosphorus cycle

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


    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

  6. The phosphorus cost of agricultural intensification in the tropics.

    Roy, Eric D; Richards, Peter D; Martinelli, Luiz A; Coletta, Luciana Della; Lins, Silvia Rafaela Machado; Vazquez, Felipe Ferraz; Willig, Edwin; Spera, Stephanie A; VanWey, Leah K; Porder, Stephen


    Agricultural intensification in the tropics is one way to meet rising global food demand in coming decades(1,2). Although this strategy can potentially spare land from conversion to agriculture(3), it relies on large material inputs. Here we quantify one such material cost, the phosphorus fertilizer required to intensify global crop production atop phosphorus-fixing soils and achieve yields similar to productive temperate agriculture. Phosphorus-fixing soils occur mainly in the tropics, and render added phosphorus less available to crops(4,5). We estimate that intensification of the 8-12% of global croplands overlying phosphorus-fixing soils in 2005 would require 1-4 Tg P yr(-1) to overcome phosphorus fixation, equivalent to 8-25% of global inorganic phosphorus fertilizer consumption that year. This imposed phosphorus 'tax' is in addition to phosphorus added to soils and subsequently harvested in crops, and doubles (2-7 Tg P yr(-1)) for scenarios of cropland extent in 2050(6). Our estimates are informed by local-, state- and national-scale investigations in Brazil, where, more than any other tropical country, low-yielding agriculture has been replaced by intensive production. In the 11 major Brazilian agricultural states, the surplus of added inorganic fertilizer phosphorus retained by soils post harvest is strongly correlated with the fraction of cropland overlying phosphorus-fixing soils (r(2) = 0.84, p < 0.001). Our interviews with 49 farmers in the Brazilian state of Mato Grosso, which produces 8% of the world's soybeans mostly on phosphorus-fixing soils, suggest this phosphorus surplus is required even after three decades of high phosphorus inputs. Our findings in Brazil highlight the need for better understanding of long-term soil phosphorus fixation elsewhere in the tropics. Strategies beyond liming, which is currently widespread in Brazil, are needed to reduce phosphorus retention by phosphorus-fixing soils to better manage the Earth

  7. 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

    Francirose Shigaki


    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

  8. Phosphorus

    Linderholm, Kersti


    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...

  9. Phosphorus recycling from wastewater to agriculture using reactive filter media

    Cucarella Cabañas, Victor


    This thesis focused on testing the suitability of reactive filter media used for phosphorus (P) removal from wastewater as fertilizers, thus recycling P to agriculture. The work compared the P sorption capacity of several materials in order to assess their suitability as a source of P for plants. The selected materials (Filtra P, Polonite and wollastonite) were saturated with P and used as soil amendments in a pot experiment. The amendments tended to improve the yield of barley and ryegrass c...

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

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


    .75–1.00 m in the nationwide 7 km Grid System in Denmark. Changes in soil P content between 1987 and 1998 at 0–0.25 and 0.25–0.50 m were also examined in 337 and 335 agricultural soil profiles, respectively. Compared to forest soils, the agricultural soils contained more total P down to 0.75 m depth (264 mg......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...... P kg− 1, or 88% more at 0–0.25 m depth, 191 mg P kg− 1 or 82% more at 0.25–0.50 m depth and 120 mg P kg− 1 or 63% more at 0.50–0.75 m depth). The mean degrees of phosphorus saturation (DPS) of the agricultural soils were 32, 23 and 15% in the three upper soil layers, which were approximately twice...

  11. Substantial dust loss of bioavailable phosphorus from agricultural soils

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


    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.

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

    Mukherjee, Chandan; Chowdhury, Rajojit; Ray, Krishna


    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

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

    Chandan eMukherjee


    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.

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

    Mukherjee, Chandan; Chowdhury, Rajojit; Ray, Krishna


    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

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

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


    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

  16. Impact of legacy phosphorus sources on diffuse phosphorus pollution from agriculture: lessons from the Chesapeake Bay watershed

    Legacy phosphorus (P), the accumulation of P in soils and sediments due to past agricultural management activities, represents an emerging challenge to ongoing efforts to mitigate diffuse P pollution from agriculture. Nutrient management programs, already tasked with minimizing the effects of today...


    Westra, John V.


    Phosphorus loads from agronomically diverse practices were simulated using representative farms from a heterogenous watershed of the Minnesota River. Results from integrated bioeconomic analyses were used to test hypotheses about nontargeted and targeted nonpoint source phosphorus pollution abatement programs, with respect to net farm income and phosphorus loading.

  18. Managing agricultural phosphorus to minimize water quality impacts

    Andrew Sharpley


    Full Text Available ABSTRACT Eutrophication of surface waters remains a major use-impairment in many countries, which, in fresh waters, is accelerated by phosphorus (P inputs from both point (e.g., municipal waste water treatment plants and nonpoint sources (e.g., urban and agricultural runoff. As point sources tend to be easier to identify and control, greater attention has recently focused on reducing nonpoint sources of P. In Brazil, agricultural productivity has increased tremendously over the last decade as a consequence, to a large extent, of increases in the use of fertilizer and improved land management. For instance, adoption of the “4R” approach (i.e., right rate, right time, right source, and right placement of P to fertilizer management can decrease P runoff. Additionally, practices that lessen the risk of runoff and erosion, such as reduced tillage and cover crops will also lessen P runoff. Despite these measures P can still be released from soil and fluvial sediment stores as a result of the prior 10 to 20 years’ management. These legacy sources can mask the water quality benefits of present-day conservation efforts. Future remedial efforts should focus on developing risk assessment indices and nonpoint source models to identify and target conservation measures and to estimate their relative effectiveness. New fertilizer formulations may more closely tailor the timing of nutrient release to plant needs and potentially decrease P runoff. Even so, it must be remembered that appropriate and timely inputs of fertilizers are needed to maintain agricultural productivity and in some cases, financial support might also be required to help offset the costs of expensive conservation measures.

  19. Legacy Phosphorus in Agricultural Watersheds: Implications for Restoration and Management of Wetlands and Aquatic Systems

    Phosphorus is added to watersheds in various forms, including fertilizers, nonhazardous wastes (animal manures and biosolids) and nutrient enriched waters. Globally, approximately 14 million metric tons of phosphorus is added as fertilizer to agricultural watersheds. The approximate ratio of nitrogen to phosphorus fertilizer application at the global level is 5.8 (Mullins et al., 2005). Historically, organic wastes such as animal manure were applied to agronomic crops and pastures on the basis of their nitrogen availability, which has resulted in excessive application of phosphorus. The nitrogen to phosphorus ratio of manure is less than 2. As a result, many agricultural watersheds receiving land application of wastes and fertilizers have accumulated phosphorus in excess amounts. However, as soils in agricultural watersheds become saturated or overloaded with phosphorus, a significant portion of stored phosphorus can be released and transported with water during runoff events into adjacent water bodies such as wetlands, streams, shallow lakes and other aquatic systems (Carpenter et al., 1998; Foley et al., 2005). Wetlands, riparian zones and water conservation areas in agricultural watersheds serve as sinks, sources and transformers of nutrients and other chemical contaminants, and as such, they can have a significant impact on water quality, nutrient retention and ecosystem productivity. Here we briefly present a case study of water quality issues in the Lake Okeechobee Basin (LOB), FL, USA and its impact on an adjacent lake.

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

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


    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

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

    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.

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

    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 ...

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

    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...... 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....... 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...

  4. Mitigating Agricultural Phosphorus Leaching : The Effect of Timing in Grass Harvesting in Mitigating Wintertime Phosphorus Leaching

    Yli-Heikkilä, Katariina


    The purpose of this thesis was to study how much the above-ground grass biomass, harvested at different times during the growing season, contains phosphorus at the end of the growing season, and how much of it is leached after freezing and thawing. The study aims to give information about the ideal time for grass harvesting in order to mitigate the wintertime phosphorus leaching. The grass biomass was harvested from managed uncultivated arable field at MTT Agrifood Research Centre experi...

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

    Sattari, S.Z.


    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

  6. Identification and modelling of processes controlling dissolved phosphorus transfer in an agricultural catchment

    Dupas, Rémi


    Phosphorus (P) is a controlling factor of eutrophication. Its presence in water bodies is partly due to agricultural diffuse emissions. The objective of this thesis was to identify and quantify the processes controlling diffuse P transfer, with an approach combining analysis of multi-scale observation data and modelling.Analysis of a water chemistry time series acquired at the outlet of a small agricultural catchment revealed that particulate and dissolved P forms had different spatial origin...

  7. The role of subsoil properties for phosphorus leaching in agricultural soils

    Andersson, Helena


    Phosphorus (P) leaching from agricultural land is a large contributor to eutrophication of many surface waters and the Baltic Sea. Better knowledge of P sorption and release in the subsoil could enable the development of effective mitigation strategies for P leaching. This thesis examined the impact of soil properties on P leaching from four Swedish agricultural soils (two clays, two sands), using intact soil columns extracted with (length 1.05 m) and without (length 0.77 m) topsoil. The role...


    Krzysztof Pulikowski


    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%.

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

    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.

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

    Chen, M; Chen, J


    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. PMID:18495999

  11. Estimation of national and regional phosphorus budgets for agriculture in Turkey

    Fethi Saban Ozbek


    Full Text Available This paper presents national and regional phosphorus (P budgets for agriculture in Turkey by using Eurostat/OECD common methodology. Regional P budgets presented in this paper are the first estimations for Turkey known to date. In Turkey, the values of P surplus for agriculture (PS and P use efficiency for agriculture (PUE in 2011 were 2 kg P ha-1 yr-1 and 77%, respectively. PS values varied from -2 to 15 kg P ha-1 yr-1 among regions in 2011. In 2008, PS and PUE values (0 kg P ha-1 yr-1 and 96%, respectively were lower than the average EU values (3 kg P ha-1 yr-1 and 104%, including Norway and Switzerland. The relationship between PS values and some socio-economic properties in Turkey regions were also analyzed. According to the results, the correlations of PS with gross domestic product per capita, permanent meadows and pastures share in utilized agricultural area (UAA, population density, illiterate share and arable land share in UAA were statistically significant. We can conclude from the study results that the environmental effect of agricultural phosphorus on water bodies varies greatly both among regions in Turkey and among European countries because of high variations in PS values.

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

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


    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

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

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

    drainage. The Danish “SUPREME-TECH” project (2010-2016) ( aims at providing the scientific basis for developing cost-effective filter technologies for P in agricultural drainage waters. The project studies different approaches of implementing filter technologies including drainage well......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...... environmental threshold values (<0.05 mg P L-1) at variable P loads and flow regimes. Intragranular diffusion made a substantial contribution to P retention and was an important filter material property. During long-term P-loading the sensitivity of flow-rate on P retention increased and further indicated the...

  14. Nitrogen and phosphorus losses from agricultural systems in China: a meta-analysis.

    Cao, Di; Cao, Wenzhi; Fang, Jing; Cai, Longyan


    Studies worldwide have indicated that agricultural pollution is the main source of nitrogen and phosphorus (N and P) in surface waters. A systematic understanding of N and P sources and sinks in agricultural systems is important for selecting the appropriate remedial strategies to control nutrient losses and water pollution. Based on nationwide data and a long-term monitoring program in Southeast China, the nationwide spatial and temporal patterns of N and P losses and the relationships between such losses and N and P inputs and rainfall were analyzed. The results showed that the annual nutrient losses from agricultural systems in China strongly varied, and the N/P values ranged from 0.01 to 51.0, with a majority at approximately 0-20, and an arithmetic mean of 9.73; these values mostly overlap the suitable range of N/P (6-15) for red bloom algae. PMID:24934439

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

    Schrijver, An De; Vesterdal, Lars; Hansen, Karin Irene; Frenne, Pieter De; Augusto, Laurent; Achat, David Ludovick; Staelens, Jeroen; Baeten, Lander; Keersmaeker, Luc De; Neve, Stefaan De; Verheyen, Kris


    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......, slowly cycling P and occluded P); in particular, we addressed the timerelated alterations in the inorganic versus organic P fractions. In less than 40 years of oak forest development, significant redistributions have occurred between different P fractions. While both the labile and the slowly cycling...

  16. Food, Feed, or Fuel? Phosphorus Flows Embodied in US Agricultural Production and Trade

    MacDonald, G.; Bennett, E.; Carpenter, S.


    Agricultural phosphorus (P) use is integral to sustainable food production and water quality regulation. Globalization of agricultural systems, changing diets, and increasing biofuel production pose new challenges for managing non-renewable P reserves, particularly in key agricultural producing regions such as the US. We used a detailed model of the US agricultural system to assess the quantity of mineral P fertilizers used to produce food crops, livestock, and biofuels relative to the P ultimately consumed in domestic diets. We also quantified linkages in fertilizer use between the US and its trading partners globally via agricultural trade. Feed and livestock production drove by far the largest demand for P fertilizers in the US (56% of all P use for domestic and imported products). Of the total mineral P inputs to US domestic agriculture in 2007 (1905 Gg P), 28% were retained in agricultural soils as surplus P, 40% were lost through processing and waste prior to consumption in human diets, while 10% were diverted directly to biofuel production. One quarter of P fertilizer in the US was required to produce exports, particularly major food and feed crops (corn, soybean, and wheat) that drove a large net P flux out of the country (338 Gg P) with strongly crop-specific effects on soil P imbalances nationally. However, US meat consumption involved considerable reliance on P fertilizer use in other countries to produce red meat imports linked primarily to soil P surpluses abroad. We show that changes in domestic farm management and consumer waste could together reduce the P fertilizer needed to produce food consumed in the US by half, which is comparable to the P fertilizer reduction attainable by cutting domestic meat consumption (44%). More effective distribution of P use for major crops nationally and greater recycling of all agricultural wastes is critical to using US phosphate rock reserves as efficiently as possible while maintaining export-oriented agriculture.

  17. Animation-based Sketching

    Vistisen, Peter

    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 be...

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

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


    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

  19. Attenuation of Diffuse Phosphorus Transfers within an Agricultural Karst Spring Zone of Contribution

    Mellander, Per-Erik; Jordan, Philip; Melland, Alice R.; Murphy, Paul N. C.; Mechan, Sarah; Meehan, Robert; Kelly, Coran; Shine, Oliver; Shortle, Ger


    This study investigated the apparent contradiction of good water quality (as determined from phosphorus (P) concentrations) and relatively intensive agriculture and high soil P status in a 32 km2 karst spring zone of contribution where groundwater vulnerability mapping had indicated high and extreme risk of pollution. Phosphorus attenuation potential was investigated along the nutrient transfer continuum based on soil P buffering, depth to bedrock and retention within the aquifer. Surface karst features such as enclosed depressions, were reclassified based on P attenuation potential in soil at the base. New techniques of high temporal resolution monitoring of P loads in the emergent spring made it possible to estimate P transfer pathways and retention within the aquifer. For one major winter flow event, an estimated 56% of both total P (TP) and total reactive P (TRP) were transported via small-medium fissure flow, and 15.5 kg (36%) of TP and 11.0 kg (42%) of TRP was retained in the limestone aquifer. A revised groundwater vulnerability assessment was used to produce a specific P susceptibility map and the definition of critical source areas in karst landscapes was demonstrated.

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

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


    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

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

    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.


    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

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

    Hansen, Line Block

    Loss of phosphorus (P) from the agricultural sector has, in recent decades, caused eutrophication of streams and lakes across Europe and North America. Intensive and increasing livestock production generates manure P well in excess of crop requirements. These areas are therefore key elements in the...... transporting and applying manure to fields means that increasing mineral-fertilizer prices does not generate a sufficient incentive for farmers to reallocate all P surpluses generated by livestock between farms and fields. The aim of the thesis is to increase the understanding of the long-term impacts of...... a tax on P surplus (this time defined as the difference between applied P and the level of P application recommended when soil P is taken into account). The two incentives are compared in terms of their effect on different environmental and production-related parameters over a 30-year period. The...

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

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


    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).

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

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


    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

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


    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.

  6. Mitigating diffuse phosphorus transfer from agriculture according to cost and efficiency.

    Haygarth, P M; Apsimon, H; Betson, M; Harris, D; Hodgkinson, R; Withers, P J A


    Potential options for mitigating phosphorus (P) transfer from agriculture to water in England and Wales (E&W) were collated across a range of farm systems to assess their potential effectiveness in reducing mass of P transferred and potential cost (pounds sterling [ pound]) to the farming industry. A simple model framework (called PEASE) incorporating a number of assumptions was used to identify 15 methods for mitigating inputs of P to agricultural systems, 19 methods for preventing mobilization of P, and six methods for controlling the transport of P to streams. The scope for largest reductions in P inputs was to grassland and horticulture. Potential reductions in P mobilization were up to 1.2 kg P ha(-1). Reductions in P transfer associated with transport mitigation were larger than those associated with input and mobilization methods (up to 2.2 kg P ha(-1)). The largest estimated reductions were achieved by installing buffer zones and constructed wetlands, the former being very cost effective ( pound3-5 kg(-1) P saved). Plots of cost curves helped identify where the combined and cumulative P transfer reductions were attainable; these were approximately 0.2 kg ha(-1) for uplands, 0.6 kg ha(-1) for outdoor pigs, 0.9 kg ha(-1) for intensive dairy, and 2.2 kg ha(-1) for arable examples. We concluded that established catchment-scale evidence for mitigation is sparse, especially for specific farm systems in E&W. Sensitivities and uncertainties in the approach, especially associated with expert coefficients, are noted. This approach is nonetheless considered useful for prioritizing where and how best options might be most effectively targeted for least cost but greatest benefit. PMID:19704144

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

    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

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

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


    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. PMID:23178830

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

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


    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

  10. Assessment of phosphorus transfer from agricultural lands to the surface water in France: definition of connectivity indices

    Delmas, M.; Gascuel-Odoux, C.; Cerdan, O.; Arrouays, D.; Mouchel, J. M.


    Diffuse phosphorus (P) transfer from agricultural lands to surface water contributes to eutrophication. It has increased attention in the last decades, notably due to a real improvement of water treatment from urban areas which induce a higher relative part of agricultural sources. Methodologies focusing on P transfer from agricultural areas to rivers are thus required, particularly for water quality assessments at large scale, as a part of the implementation of the EU Water Framework Directive. In this context, a methodology is presented which aims to investigate what is the fraction of hillslope P production which reaches the river systems, and finally, to better identify the origin of P observed in rivers. The proposed model combines mobilisation and transfer processes: P and soil particles are firstly mobilised by water erosion, and then they are delivered via surface and sub-surface flow pathways to the river network. The method takes into account the spatial distribution of major properties that control the mobilisation of P by soil erosion and its transfer to the water bodies. Description of P transfer is based on the establishment of connectivity indicators which describe hillslope flow pathways, potential retention, attempting to link basin characteristics to a prediction of phosphorus exports in rivers. The model is calibrated and validated with phosphorus fluxes calculated in French rivers. This study provides insight in the identification of the most influent soil particles and P redistribution processes on the total P fluxes, and the difference between various types of basins.

  11. Influence of Antecedent Hydrologic Conditions on Nitrate and Phosphorus Export from a Small Agricultural Catchment in Southern Ontario, Canada

    Macrae, M. L.; English, M. C.; Schiff, S. L.; Stone, M.


    The ability of the scientific community to quantify and predict discharge and nutrient transport in a range of settings is confounded by the effects of antecedent hydrologic conditions in upland areas. Previous work has empirically linked spatial variables such as land use, soil type, topography, and drainage characteristics to hydrochemical export from various landscapes (e.g. MCDOWELL et al., 2001; ARHEIMER and LIDEN, 2000; STAMM et al., 1998; JORDAN et al., 1997; WELSCH et al., 2001). However, the specific reasons why similar types of events produce different nutrient export patterns are poorly understood. Nutrient (nitrate, soluble and total phosphorus) transport from agricultural catchments is difficult to quantify and predict because of the influence of variable hydrologic flowpaths and their interaction with varying nutrient pools. This research examines the role of antecedent hydrologic conditions on stream discharge and nitrate (NO3-), soluble reactive phosphorus (SRP) and total phosphorus (TP) export from a small (2.7 km2) first-order agricultural catchment in Southern Ontario, Canada. During 59 events occurring over a two-year sampling period (year-round), runoff ratios ranged from 0-0.99). Runoff ratios increased throughout successive events as conditions became wetter although key indices of antecedent wetness such as water table position, pre-event streamflow and soil moisture did not yield predictive relationships. Nitrate, SRP and TP transport from the catchment increased with antecedent wetness during some periods but decreased with antecedent wetness during other periods. This variability appears to be linked to a combination of the position of water table before and during the event, as well as timing of fertilizer application. It is hypothesized that in general, wetter antecedent hydrologic conditions increase nutrient transport from the catchment by increasing macropore connectivity between surface soil horizons and tile drains, although this

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

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


    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...

  13. Using radiometric tools to track sediment and phosphorus movement in an agricultural watershed

    Huisman, Natalie L. H.; Karthikeyan, K. G.


    SummaryIncreased levels of phosphorus (P) in freshwater systems generally cause eutrophication leading to algal blooms, fish kills, and decreased biodiversity. Point sources have been fairly well characterized; however, non-point sources (NPS), such as agricultural fields, require further study to ascertain the origin and physicochemical forms of P. During a single storm event in June 2008 in a small Wisconsin agricultural watershed (12.4 km2), a comprehensive study was performed to characterize sediment and P transport dynamics. In addition to standard analytical techniques to quantify sediment and P transport, the atmospheric fallout radionuclides (7Be, 210Pbxs, and 137Cs) were employed to determine sediment origin and in-stream transport parameters. Sediments originated primarily from surficial upland soils, or cultivated fields, with minor contributions of resuspended streambed sediments and no discernable stream bank contributions. Sediments were deposited onto the streambed during this event, creating a temporary store, which could be resuspended during subsequent flow events. While for this moderate storm event the stream channels exhibited a short-term depositional behavior they appeared erosional in nature over longer time periods. Particulate-bound P was found to be 33-46% of the total P (TP) transported in the stream channel. The mean dissolved P and TP concentrations at the two stream sites ranged from 0.99 ± 0.32 mg L-1 to 1.14 ± 0.63 mg L-1 and 1.77 ± 0.78 mg L-1 to 1.83 ± 0.78 mg L-1, respectively. During baseflow conditions, the mean dissolved reactive P (DRP) and TP concentrations were quite high, 0.27 ± 0.02 mg L-1 and 0.33 ± 0.04 mg L-1, respectively, exceeding recommended USEPA TP levels (0.08 mg L-1; USEPA, 2000) for eutrophication threshold. Overall, significant transport of P in both dissolved and particulate forms occurred during this moderate stormflow event. We assert that improved upland conservation practices are necessary to

  14. Capture and characterization of particulate phosphorus from farm drainage waters in the Everglades Agricultural Area

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


    The buildup of highly labile, organic, phosphorus (P)-enriched sediments in farms canals within the Everglades Agricultural Area (EAA) has been associated with the production of floating aquatic vegetation. During drainage events, these sediments are susceptible to transport and contribute to the overall P load. In order to evaluate the total P load exiting the farm canals, a settling tank experiment was conducted to capture the sediments during drainage events from eight farms. Drainage water was channelized through two 200L polypropylene collection tanks which allowed sediments to settle at the bottom based on its particle size. Water was carefully siphoned out of the tanks and the sediments collected for analyses. A five step P-fractionation process was used to distinguish organic (o) and inorganic (i) forms of P: KCl extractable P, NaOH extractable P, HCl extractable P, and residual P. The KCl-Pi fraction represents the labile Pi that is water soluble and exchangeable (loosely adsorbed); NaOH extractable P represents Fe- and Al- bound inorganic P (NaOH-Pi) and organic P associated with humic and fulvic acids (NaOH-Po). The HCl-Pi fraction includes Ca- and Mg- bound P, while Residue-P represents recalcitrant organic P compounds and P bound to minerals. The sediments were also used to conduct a P-flux study under both aerobic and anaerobic conditions. Our goal is to provide growers with vital information and insight into P loading that will help them in their efforts to reduce off-farm P loads in the EAA.

  15. Phosphorus and water management in soil under no-till agriculture

    Under no-till conservation agricultural practices, crop residues are returned to the soil's surface whereas under conventional tillage they are mixed within the top ploughed layer (5-20 cm depth). Moreover, P fertilizer drilled in the soil at sowing of the previous crop is also mixed in ploughed soil while in no-till it concentrates in rows or slits, usually near the soil surface. Generally, this results in the stratification of phosphorus with depth under no-till more than under CT. In a semi-arid region, where topsoil layer remains dry for prolonged periods during crop growth, the possibility exists that plant roots may not be able to access the fertiliser P stranded in the dry layer. For example, Strong et al. (1997) showed that residual fertiliser value of P applied in the previous year was only 20-40% under low soil water regime to that of well-watered soil. However, water use efficiency increases as the P application increases in P responsive soils. Water use efficiency is generally higher under no-till than CT practice in semi-arid regions (Gibson et al. 1992; Norwood 1999). In spite of these findings, with adequate P fertilisation of crops, the drying of the topsoil layer does not appear to be a limiting factor for crop production (Weil et al. 1988). On the other hand, repeated P application in a limited area of soil and without further mixing with soil under NT results in enhanced P uptake and greater grain yields (Hargrove 1985). Controlled traffic under NT practice may prove to be even more beneficial in soils with high P sorption capacity since only the limited soil volume is fertilized

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

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


    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

  17. New insights into phosphorus management in agriculture--A crop rotation approach.

    Łukowiak, Remigiusz; Grzebisz, Witold; Sassenrath, Gretchen F


    This manuscript presents research results examining phosphorus (P) management in a soil–plant system for three variables: i) internal resources of soil available phosphorus, ii) cropping sequence, and iii) external input of phosphorus (manure, fertilizers). The research was conducted in long-term cropping sequences with oilseed rape (10 rotations) and maize (six rotations) over three consecutive growing seasons (2004/2005, 2005/2006, and 2006/2007) in a production farm on soils originated from Albic Luvisols in Poland. The soil available phosphorus pool, measured as calcium chloride extractable P (CCE-P), constituted 28% to 67% of the total phosphorus input (PTI) to the soil–plant system in the spring. Oilseed rape and maize dominant cropping sequences showed a significant potential to utilize the CCE-P pool within the soil profile. Cropping sequences containing oilseed rape significantly affected the CCE-P pool, and in turn contributed to the P(TI). The P(TI) uptake use efficiency was 50% on average. Therefore, the CCE-P pool should be taken into account as an important component of a sound and reliable phosphorus balance. The instability of the yield prediction, based on the P(TI), was mainly due to an imbalanced management of both farmyard manure and phosphorus fertilizer. Oilseed rape plants provide a significant positive impact on the CCE-P pool after harvest, improving the productive stability of the entire cropping sequence. This phenomenon was documented by the P(TI) increase during wheat cultivation following oilseed rape. The Unit Phosphorus Uptake index also showed a higher stability in oilseed rape cropping systems compared to rotations based on maize. Cropping sequences are a primary factor impacting phosphorus management. Judicious implementation of crop rotations can improve soil P resources, efficiency of crop P use, and crop yield and yield stability. Use of cropping sequences can reduce the need for external P sources such as farmyard manure

  18. The significance of the differences in soil phosphorus representation and transport procedures in the SWAT and HSPF models and a comparison of their performance in estimating phosphorus loss from an agriculture catchment in Ireland

    Nasr, Ahmed Elssidig; Bruen, Michael; Moles, Richard; Byrne, Paul; O'Regan, Bernadette


    Phosphorus transported from agriculture land has been identified as a major source of water pollution in a large number of Irish catchments. Models of this process are required in order to design and assess management measures. This paper reports on the comparison and assessment of two of the most promising physically-based distributed models, SWAT and HSPF, with particular emphasis on their suitability for Irish conditions. The representation of the overall soil phosphorus cycle is similar i...

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

    Vandermoere, Stany; De Neve, Stefaan


    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.

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

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


    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.

  1. Monitoring changes in soil organic carbon pools, nitrogen, phosphorus, and sulfur under different agricultural management practices in the tropics.

    Verma, Bibhash C; Datta, Siba Prasad; Rattan, Raj K; Singh, Anil K


    Soil organic matter not only affects sustainability of agricultural ecosystems, but also extremely important in maintaining overall quality of environment as soil contains a significant part of global carbon stock. Hence, we attempted to assess the influence of different tillage and nutrient management practices on various stabilized and active soil organic carbon pools, and their contribution to the extractable nitrogen phosphorus and sulfur. Our study confined to the assessment of impact of agricultural management practices on the soil organic carbon pools and extractable nutrients under three important cropping systems, viz. soybean-wheat, maize-wheat, and rice-wheat. Results indicated that there was marginal improvement in Walkley and Black content in soil under integrated and organic nutrient management treatments in soybean-wheat, maize-wheat, and rice-wheat after completion of four cropping cycles. Improvement in stabilized pools of soil organic carbon (SOC) was not proportional to the applied amount of organic manures. While, labile pools of SOC were increased with the increase in amount of added manures. Apparently, green manure (Sesbania) was more effective in enhancing the lability of SOC as compared to farmyard manure and crop residues. The KMnO(4)-oxidizable SOC proved to be more sensitive and consistent as an index of labile pool of SOC compared to microbial biomass carbon. Under different cropping sequences, labile fractions of soil organic carbon exerted consistent positive effect on the extractable nitrogen, phosphorus, and sulfur in soil. PMID:20069448

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

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


    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

  3. Using flue gas desulfurization gypsum to remove dissolved phosphorus from agricultural drainage waters

    After several decades of applying chicken litter to meet crop demands for nitrogen, high levels of legacy phosphorus (P) in soils of the Delmarva Peninsula are a major source of dissolved P entering drainage ditches that empty to the Chesapeake Bay. The objective of this study was to design, constru...

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

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


    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

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

    Hong-Bing Luo


    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.

  6. 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

    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...

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

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


    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

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

    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)

  9. Application of nitrogen and phosphorus criteria for streams in agricultural landscapes.

    Chambers, P A; Benoy, G A; Brua, R B; Culp, J M


    Efforts to control eutrophication of water resources in agriculturally dominated ecosystems have focused on managing on-farm activities to reduce nutrient loss; however, another management measure for improving water quality is adoption of environmental performance criteria (or 'outcome-based standards'). Here, we review approaches for setting environmental quality criteria for nutrients, summarize approaches developed in Canada for setting 'ideal' and 'achievable' nutrient criteria for streams in agricultural watersheds, and consider how such criteria could be applied. As part of a 'National Agri-Environmental Standards Initiative', the Government of Canada committed to the development of non-regulatory environmental performance standards that establish total P (TP) and total N (TN) concentrations to protect ecological condition of agricultural streams. Application of four approaches for defining ideal standards using only chemistry data resulted in values for TP and TN spanning a relatively narrow range of concentrations within a given ecoregion. Cross-calibration of these chemically derived standards with information on biological condition resulted in recommendations for TP and TN that would likely protect aquatic life from adverse effects of eutrophication. Non-point source water quality modelling was then conducted in a specific watershed to estimate achievable standards, i.e. chemical conditions that could be attained using currently available and recommended management practices. Our research showed that, taken together, short-term achievable standards and ultimate ideal standards could be used to set policy targets that should, if realized, lower N and P concentrations in Canadian agricultural streams and improve biotic condition. PMID:22156121

  10. Long-term manure application effects on phosphorus speciation, kinetics and distribution in highly weathered agricultural soils.

    Abdala, Dalton Belchior; da Silva, Ivo Ribeiro; Vergütz, Leonardus; Sparks, Donald Lewis


    Phosphorus (P) K-edge XANES and Fe K-edge EXAFS spectroscopies along with sequential P chemical fractionation and desorption kinetics experiments, were employed to provide micro- and macro-scale information on the long-term fate of manure application on the solid-state speciation, kinetics and distribution of P in highly weathered agricultural soils of southern Brazil. Soil test P values ranged from 7.3 up to 16.5 times as much higher than the reference soil. A sharp increase in amorphous Fe and Al amounts were observed as an effect of the consecutive application of manures. Whereas our results showed that the P sorption capacity of some manured soils was not significantly affected, P risk assessment indices indicated that P losses should be expected, likely due to the excessive manure rates applied to the soils. The much higher contents of amorphous Fe and Al (hydr)oxides (55% and 80% increase with respect to the reference soil, respectively) in manured soils seem to have counterbalanced the inhibiting effect of soil organic matter on P sorption by creating additional P sorption sites. Accordingly, the newly created P sorbing surfaces were important to prevent an even larger P loss potential. Phosphorus K-edge XANES lent complimentary hints on the loss of crystallinity and transformation of originally present Fe-P minerals into poorly crystalline ones as an effect of manuring, whereas Fe K-edge EXAFS provided insights into the structural changes underwent in the soils upon manure application and soil management. PMID:25112576

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

    Goyenola, G.; Meerhoff, M.; Teixeira-de Mello, F.;


    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...... 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...

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

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


    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

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

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


    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

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

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


    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.

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

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


    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

  16. Methods and Possibility for Recycling of Phosphorus from Sludge

    Chapagain, Yogesh


    This thesis presents a review of the phosphorus cycle, environmental effect of excess phosphorus on environment, different methods approach taken to recover phosphorus compound from waste sludge, and possible uses for recovered phosphorus. Phosphorus is a critical nutrient for the agricultural production and living organism survival. The use of phosphorus in fertilizer secures future food demand but threatens water resources. The uncontrolled use of agricultural phosphorus and commercial...

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

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


    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

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

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


    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

  19. The strategic significance of wastewater sources to pollutant phosphorus levels in English rivers and to environmental management for rural, agricultural and urban catchments

    The relationship between soluble and particulate phosphorus was examined for 9 major UK rivers including 26 major tributaries and 68 monitoring points, covering wide-ranging rural and agricultural/urban impacted systems with catchment areas varying from 1 to 6000 km2 scales. Phosphorus concentrations in Soluble Reactive (SRP), Total Dissolved (TDP), Total (TP), Dissolved Hydrolysable (DHP) and Particulate (PP) forms correlated with effluent markers (sodium and boron) and SRP was generally dominant signifying the importance of sewage sources. Low flows were particularly enriched in SRP, TDP and TP for average SRP > 100 μg/l indicating low effluent dilution. At particularly low average concentrations, SRP increased with flow but effluent sources were still implicated as the effluent markers (boron in particular) increased likewise. For rural areas, DHP had proportionately high concentrations and SRP + DHP concentrations could exceed environmental thresholds currently set for SRP. Given DHP has a high bioavailability the environmental implications need further consideration. PP concentrations were generally highest at high flows but PP in the suspended solids was generally at its lowest and in general PP correlated with particulate organic carbon and more so than the suspended sediment in total. Separation of pollutant inputs solely between effluent and diffuse (agriculture) components is misleading, as part of the 'diffuse' term comprises effluents flushed from the catchments during high flow. Effluent sources of phosphorus supplied directly or indirectly to the river coupled with within-river interactions between water/sediment/biota largely determine pollutant levels. The study flags the fundamental need of placing direct and indirect effluent sources and contaminated storage with interchange to/from the river at the focus for remediation strategies for UK rivers in relation to eutrophication and the WFD.

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

    Anna Orczewska; Anna Piotrowska; Joanna Lemanowicz


    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), ...

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

    Roni Fernandes Guareschi


    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.

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

    F. Amaral; M. Abelho


    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).

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

    C. Hahn


    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.

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

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


    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.

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

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


    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

  6. Ethics in Animal-Based Research.

    Gross, Dominik; Tolba, René H


    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

  7. Agriculture

    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

  8. Effects of lowering nitrogen and phosphorus surpluses in agriculture on the quality of groundwater and surface water in the Netherlands

    Oenema, Oene; van Liere, Lowie; Schoumans, Oscar


    The ecological status of many surface waters in the Netherlands (NL) is poor, due to relatively high discharges of N and P from agriculture, industry and wastewater treatment plants. Agriculture is suggested to be a major source, as discharges from industry and wastewater treatment plants have sharply decreased from the 1980s onwards. Agricultural land covers more than 60% of the total surface area in NL, and most of this land is managed intensively and is intersected by a dense network of ditches (total length ˜300,000 km), streams and lakes. On average, groundwater levels are shallow to very shallow. It has been suggested that nutrient balances of agricultural land are easy to measure proxies for nutrient discharges from agricultural land, though the relationships between nutrient balances and nutrient discharges into groundwater and surface water are not well-established. Thus, we explored the effects of lowering N and P surpluses in NL agriculture on the quality of groundwater and surface waters. Effects of N surpluses in the range of 40-300 kg ha -1 yr -1, and of P surpluses in the range of 0.4-17.5 kg of P per ha per year were examined using an integrated set of mathematical models and databases. Results indicate that nitrate leaching to groundwater and N and P discharges to surface waters are related to both N and P surpluses, hydrological condition, land use and soil type. On a national scale, decreasing N surplus by 1 kg ha -1, decreased nitrate leaching to groundwater on average by 0.08 kg ha -1 and N leaching to surface waters on average by 0.12 kg ha -1. Decreases of N and P concentrations in surface waters upon lowering surpluses were smaller than the calculated discharges. Decreases in N and P concentrations were much smaller in the coastal zone and Lake IJsselmeer, than in regional waters (ditches and small streams). The small improvement in the quality of surface waters upon lowering surpluses in agriculture is related to the relative importance of

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

    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

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

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


    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).

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

    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

  12. Animal-based measures for welfare assessment

    Agostino Sevi


    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

  13. Bioavailability and fate of phosphorus in constructed wetlands receiving agricultural runoff in the San Joaquin Valley, California.

    Maynard, Jonathan J; O'Geen, Anthony T; Dahlgren, Randy A


    Elevated nutrient concentrations in agricultural runoff contribute to seasonal eutrophication and hypoxia in the lower portion of the San Joaquin River, California. Interception and filtration of agricultural runoff by constructed wetlands may improve water quality of return flows ultimately destined for major water bodies. This study evaluated the efficacy of two small flow-through wetlands (2.3 and 7.3 ha; hydraulic residence time = 11 and 31 h) for attenuating various forms of P from irrigation tailwaters during the 2005 irrigation season (May to September). Our goal was to examine transformations and removal efficiencies for bioavailable P in constructed wetlands. Inflow and outflow water volumes were monitored continuously and weekly water samples were collected to measure total P (TP), dissolved-reactive P (DRP), and bioavailable P (BAP). Suspended sediment was characterized and fractionated into five operationally-defined P fractions (i.e., NH4Cl, bicarbonate-dithionite, NaOH, HCl, residual) to evaluate particulate P (PP) transformations. DRP was the major source of BAP with the particulate fraction contributing from 11 to 26%. On a seasonal basis, wetlands removed 55 to 65% of PP, 61 to 63% of DRP, 57 to 62% of BAP, and 88 to 91% of TSS. Sequential fractionation indicated that the bioavailable fraction of PP was largely associated with clay-sized particles that remain in suspension, while less labile P forms preferentially settle with coarser sediment. Thus, removal of potentially bioavailable PP is dependent on factors that promote particle settling and allow for the removal of colloids. This study suggests that treatment of tailwaters in small, flow-through wetlands can effectively remove BAP. Wetland design and management strategies that enhance sedimentation of colloids can improve BAP retention efficiency. PMID:19141827

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

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


    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

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

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


    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

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

    Stuart White


    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.

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

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


    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

  18. The nitrate and phosphorus response to dynamic control of tile drain levels in a Dutch lowland area with high agricultural pollution loadings

    Borren, W.; Rozemeijer, J.; Visser, A.; Broers, H.


    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Previous studies (Rozemeijer et al. 2010a,b, vdVelde 2010) revealed that tile drains are a dominant transport route for nitrate in a Dutch lowland catchment. Overland flow is an important transport route for P. Local measures aimed at reducing the solute inputs from agriculture to surface water are studied, in addition to national management approaches. We designed a small scale (1 ha) field experiment to investigate whether nutrient outflow from tile drains can be reduced by dynamically controlling the outflow level of the drains. Our hypothesis was that higher water tables in spring and summer may increase denitrification rates in the soil and reduce N fluxes, but this could also increase overland flow and P transport by reducing storage capacity. Controlling the drain levels may also promote water storage in catchments, which may enhance agricultural productivity in dry summers. In our two-year experiment we adjusted the tile drain levels for periods of 2 months or longer. We measured precipitation rates and the response of water tables and drain fluxes at the agricultural field and measured N and P concentrations continuously using auto-analyzers. This yielded continuous time series for all relevant hydrological and chemical parameters. Moreover, we measured monthly-averaged N and P concentrations using passive samplers, installed at the field experiment and in 20 drains distributed over the catchment. We concluded that raising drain outflow levels in early spring until end of summer has a positive effect on water storage in the catchment and effectively reduces nitrate outflow to the surface water by reducing the water fluxes. However, the eventual effects of reduction of nitrate fluxes and storage of water

  19. 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

    邓伟; 许振成; 吴根义; 贺德春


    [ 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.

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

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


    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

  1. Feasibility Study: Phosphorus Recovery from Household Solid Organic Waste

    Lu, Xiaoxia


    Phosphorus is an essential source with significance use in agriculture. Phosphorus is lost in the human intensified global cycle and it is important to remove phosphorus from water body. However, important and potential sources for phosphorus product which is suitable and effective for fertilizer use may be ignored due to over emphasize on the pollution prevention. This work aims to identify the potential of phosphorus recovery from solid organic waste in Sweden. Based on the result of Materi...

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

    Esralew, R.; Tortorelli, R. L.


    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

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

    Kokic, Jovana


    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...

  4. Environmental Phosphorus Recovery Based on Molecular Bioscavengers

    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...

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

    Zabrodina, Marina Vladimirovna


    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...

  6. Investigating User Experiences Through Animation-based Sketching

    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....

  7. Phosphorus Recovery from Ashes of Sewage Sludge

    Cornel, Peter; Schaum, Peter


    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)

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

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


    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...

  9. Organic and Inorganic Dietary Phosphorus and Its Management in Chronic Kidney Disease

    Nazanin Noori


    Full Text Available Dietary phosphorus control is often a main strategy in the management of patients with chronic kidney disease. Dietary protein is a major source of phosphorus intake. Recent data indicate that imposed dietary phosphorus restriction may compromise the need for adequate protein intake, leading to protein-energy wasting and possibly to increased mortality. The two main sources of dietary phosphorus are organic, including animal and vegetarian proteins, and inorganic, mostly food preservatives. Animal-based foods and plant are abundant in organic phosphorus. Usually 40% to 60% of animal-based phosphorus is absorbed; this varies by degree of gastrointestinal vitamin-D-receptor activation, whereas plant phosphorus, mostly associated with phytates, is less absorbable by human gastrointestinal tract. Up to 100% of inorganic phosphorus in processed foods may be absorbed; ie, phosphorus in processed cheese and some soda (cola drinks. A recent study suggests that a higher dietary phosphorus-protein intake ratio is associated with incremental death risk in patients on long-term hemodialysis. Hence, for phosphorus management in chronic kidney disease, in addition to absolute dietary phosphorus content, the chemical structure (inorganic versus organic, type (animal versus plant, and phosphorus-protein ratio should be considered. We recommend foods and supplements with no or lowest quantity of inorganic phosphorus additives, more plant-based proteins, and a dietary phosphorus-protein ratio of less than 10 mg/g. Fresh (nonprocessed egg white (phosphorus-protein ratio less than 2 mg/g is a good example of desirable food, which contains a high proportion of essential amino acids with low amounts of fat, cholesterol, and phosphorus.

  10. Investigating User Experiences Through Animation-based Sketching

    Vistisen, Peter; Poulsen, Søren Bolvig


    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....

  11. Robot Animals Based on Brain-Computer Interface

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


    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.

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

    Jackson, W R


    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

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

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


    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.

  14. Displacement of phosphorus in structured soils

    Djodjic, Faruk


    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...

  15. How effective are reedbeds, ponds, restored and constructed wetlands at retaining nitrogen, phosphorus and suspended sediment from agricultural pollution in England?

    Palmer-Felgate Elizabeth J


    Full Text Available Abstract A high priority topic within the Department for Environment, Food and Rural Affairs (DEFRA water quality programme is the mitigation of diffuse rural pollution from agriculture. Wetlands are often cited as being effective at reducing nutrient and sediment loadings to receiving waters. However, the research in this area is inconsistent, and whilst most studies have shown that both natural and constructed wetlands retain nutrients and sediments, others have shown that they have little effect, or even increase nutrient and sediment loads to receiving water bodies. DEFRA has commissioned a systematic review on the use of wetlands to mitigate N, P and SS inputs from agriculture to receiving freshwater in England. The review will encompass a comprehensive literature search on all available material on the subject, both published and unpublished within the British Isles. Specific inclusion criteria will be adhered to and a formal assessment of the quality and reliability of the studies will be undertaken. The data will then be extracted and a data synthesis undertaken. The review will inform an evidence-based policy that can be implemented by stakeholders.

  16. 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

    杨雪; 梅凯; 吴昊


    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.

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

    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...

  18. Sustainable use of phosphorus: a finite resource.

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


    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

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

    Shanklin, Rachel Kristina


    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...

  20. Phosphorus leaching as influenced by animal manure and catch crops

    Liu, Jian


    Leaching of phosphorus (P) constitutes an important part of P losses from Swedish agricultural soils. Phosphorus leaching is complex and is influenced by many factors, from source and mobilisation to transport pathways, as well as agricultural management practices. In order to design appropriate mitigation strategies to reduce P leaching, it is urgent to understand how different factors influence P leaching and to understand the methods for assessing P leaching. This thesis investigat...

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


    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.

  2. Use of reactive materials to bind phosphorus

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


    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


    Water-extractable phosphorus (P) in manure is strongly related to dissolved P in runoff from soils receiving recent additions of manure. A survey of water-extractable P concentrations in manures submitted to Penn State University's Agricultural Analytical Services Laboratory was conducted. Results r...

  4. 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

    Gaspar Henrique Korndörfer


    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%.

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

    Piwowar, Arkadiusz


    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.

  6. Assessing phosphorus reduction efforts in the Everglades

    Tretkoff, Ernie


    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)

  7. Developing Educational Computer Animation Based on Human Personality Types

    Sajid Musa


    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

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

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


    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

  9. Effect of phosphorus sources on phosphorus and nitrogen utilization by three sweet potato cultivars

    A greenhouse experiment was conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf, Austria using three sweet potato cultivars, TIS 2, TIS 3053 and TIS 1487. The three sweet potato cultivars were grown at two levels of phosphorus (0 kg P/kg soil and 60 kg P/kg soil). The fertilizer treatments consisted of two sources of phosphorus, Gafza rock Phosphate and triple super phosphate with 14.19 and 19.76% total phosphorus, respectively. 15N labelled urea was used to study the nitrogen recovery in tubers from the applied nitrogen fertilizer. The results from these preliminary studies indicate that there is considerable genotypic variation among cultivars in the efficiency with which phosphorus and nitrogen are taken up and used to produce biomass. Their response to different sources of phosphorus are also variable. TIS-2 and TIS-1487 have a greater ability to absorb phosphorus from Gafza rock phosphate and produce higher tube yields indicating their greater potential for using alternative sources of natural phosphate fertilizers more effectively. Gafza rock phosphate also increased accumulation of nitrogen in TIS-1487, a characteristic which will place this cultivar at an advantage when growing in soils low in nitrogen. On an overall basis taking into account tuber yield, phosphorus use efficiency, and nitrogen use efficiency, TIS-2 may be considered the better candidate for introduction into soils poor in resources particularly phosphorus. This study was conducted with a limited number of cultivars due to limitation in the availability of germplasma. In spite of this, the differences in their abilities for phosphorus and nitrogen uptake and use are clearly visible which justifies large scale screening experiments using a broader germplasm base, in the future. (author). 14 refs, 1 fig., 3 tabs

  10. Phosphorus poisoning in waterfowl

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


    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.

  11. Biogeochemistry: The fate of phosphorus

    Némery, Julien; Garnier, Josette


    Phosphorus is essential for food production, but it is also a key cause of eutrophication. Estimates of phosphorus flux for the past 40-70 years reveal that large river basins can experience phases of phosphorus accumulation and depletion.

  12. Process Based Modelling of Phosphorus Losses from Arable Land

    Ekstrand, Sam; Wallenberg, Peter; Djodjic, Faruk


    Improved understanding of temporal and spatial Phosphorus (P) discharge variations is needed for improved modelling and prioritisation of abatement strategies that take into account local conditions . This study is aimed at developing modelling of agricultural Phosphorus losses with improved spatial and temporal resolution, and to compare the accuracy of a detailed process-based model with a rainfall-runoff coefficient-based model. The process-based SWAT model (Soil and Water Assessment Tool)...



    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...

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

    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


    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.

  15. Phosphorus removal in reactive filter materials : factors affecting the sorption capacity

    Nilsson, Charlotte


    Phosphorus is an essential component in all living organisms; it is one of the components of the DNA and the key element in the energy supplying molecule adenosine triphosphate (ATP). Throughout the history, humans have been recycling phosphorus to agriculture; thereby increasing the yield, examples of this includes the burning of plants and the use of manure. Today, we rely on commercial fertilizers with high concentrations of phosphorus. The manufacturing of these products include extractio...

  16. An iron-facilitated chemical and biological process for phosphorus removal and recovery during wastewater treatment

    Zhao, Kang; 趙鈧


    Phosphorus (P) is an important pollutant of concern in wastewater that causes eutrophication and algal blooms in water body. On the other hand, P is a valuable natural resource for agricultural and industrial use. With the rapid depletion of mineral phosphorus on earth, there is a need to recover phosphorus from wastewater. In this study, a new chemical and biological process facilitated with iron dosing has been developed for P removal and recovery during wastewater treatment. The system con...

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

    Weikard, H.P.; Seyhan, D.


    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

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

    M. G. Hutchins


    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

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

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


    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

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

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


    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...

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

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


    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...

  2. Traps for phosphorus adsorption

    Several AL2O3 supported oxides such as: NiO, CuO, Co2O3 BaO, CeO2 and ZnO were investigated for phosphorus adsorption. Zno/y-Al2O3 exhibited the highest phosphorus adsorption capacity. However, since it diminishes the activity of to the reaction mixture it should be located upstream of the NoX catalyst, i.e. 0,3% Pd-H-MOR, in order to protect it against p poisoning. The treatment procedure with citric acid was effective for the removal of more than 70% phosphorus from the adsorbent, ZnO/y-Al2O3

  3. Phosphorus recycling and food security in the long run

    Weikard, Hans Peter


    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

  4. Understanding the anthropogenic phosphorus pathway with substance flow analysis at the city level.

    Yuan, Zengwei; Shi, Junkui; Wu, Huijun; Zhang, Ling; Bi, Jun


    Excessive input of phosphorus into natural water bodies as a result of anthropogenic processes is an escalating factor that leads to eutrophication. Hence, quantifying the pathway of phosphorus throughout the socioeconomic system is essential for the selection of appropriate measures to mitigate phosphorus discharge. The study develops an analytical model of anthropogenic phosphorus flows within a socioeconomic system based on substance flow analysis. The model consists of five major subsystems: the phosphorous chemical industry, agriculture, animal feeding, human consumption, and waste management. The results show that the total input and output of phosphorus in Chaohu City over 2008 are 8517.70 ton (t) and 4682.76 t, respectively. The estimation of phosphorus discharged into local surface water is 544.22 t, which primarily comes from agriculture (391.99 t, 72.03%), followed by large-scale farming (55.70 t, 10.23%), rural consumption (56.81 t, 10.44%), urban consumption (30.42 t, 5.59%), and waste management (9.30 t, 1.71%). Intensive input of fertilizers in agricultural practices was identified as the most important source of phosphorus load on local surface water. Hence, we propose that the eutrophication of local water bodies could be addressed by optimizing local industrial structure, developing ecological and organic-based agriculture, and improving waste collection and disposal practices. PMID:21489683

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

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


    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

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

    Bracke, M.B.M.


    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

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

    Umme Aiman


    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.

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

    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)


    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

  9. Global baseline data on phosphorus pollution of large lakes

    Fink, Gabriel; Flörke, Martina; Alcamo, Joseph


    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.

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

    Stuart White; Dana Cordell


    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...

  11. Alternative, non-animal based nutrient sources, for organic plant raising OF0308



    Organic plant raising has been investigated under two previous government funded projects (OF0109 & OF0144) (1, 2) and it was shown in this research that organic ‘transplants’ could be produced for a range of crop species (3, 4, 6, 7). However, some species were easier to produce than others and one of the limiting factors was the availability of suitable nutrient sources, especially for supplementary feeding. The use of animal based nutrient sources in organic plant raising has always bee...

  12. Use of animal based measures for the assessment of dairy cow welfare ANIBAM

    Nielsen , Bodil Højlund; Angelucci, Alessandra; Scalvenzi , Alessandra; Forkman, Björn; Fusi , Francesca; Tuyttens, Frank; Houe, Hans; Blokhuis, Harry; Sørensen, Jan Tind; Rothmann, Janne; Matthews, Lindsay; Mounier, Luc; Bertocchi, Luigi; Richard, Marie Madeleine; Donati, Matteo


    The overall aim of the project was to evaluate the use of routinely collected animal based measures (ABMs) for an evaluatio n of the overall animal welfare in dairy cow herds. ABMs being able to detect worst adverse effects in relation to animal welfare were identified based on the existing literature and expert opinion. The validity and robustness of these ABMs were evaluated and cow mortality, somatic cell count and lameness were selected for further study. A number of fac...

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

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


    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.

  14. Multiple phosphorus chemical sites in heavily phosphorus-doped diamond

    We have performed high-resolution core level photoemission spectroscopy on a heavily phosphorus (P)-doped diamond film in order to elucidate the chemical sites of doped-phosphorus atoms in diamond. P 2p core level study shows two bulk components, providing spectroscopic evidence for multiple chemical sites of doped-phosphorus atoms. This indicates that only a part of doped-phosphorus atoms contribute to the formation of carriers. From a comparison with band calculations, possible origins for the chemical sites are discussed.

  15. Phosphorus in prebiotic chemistry

    Schwartz, Alan W


    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...

  16. Phosphorus in pig diets

    Lyberg, Karin


    Pig feed is mainly based on cereals where phosphorus (P) is mostly present in inositol hexaphosphate (IP6), which is not readily available to monogastric animals. More available P sources are often added to ensure that pigs’ requirements are fulfilled; this results in high excretion levels of P. The digestibility of P depends on phytase activity and amount of IP6 in feedstuffs. The overall aim was to study effects of liquid feeding, P levels and phytase supplementation on digestibility and pe...

  17. Predicting phosphorus dynamics in complex terrains using a variable source area hydrology model

    Prediction of phosphorus (P) loss from agricultural watersheds depends on accurately representing the processes governing P loss from agricultural watersheds and the particular transport factors facilitating loss. The Soil and Water Assessment Tool (SWAT), a model commonly used to predict runoff an...

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

    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)

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

    Kalmykova, Yuliya; Fedje, K Karlfeldt


    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

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

    EFSA Panel on Animal Health and Welfare


    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.

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

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


    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...


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


    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.

  3. Sustainability of phosphorus fertilisation: sources and forms of phosphate

    Monteiro, M.C.H.


    Phosphorus (P), which originates from a non-renewable natural resource, is essential for crop productivity, food security and human health, despite being a finite resource its use has been increasing consistently over the last few decades. The major use of the phosphate rock is the manufacture of P fertiliser, agriculture also being the main source for nonpoint source P pollution, which causes the eutrophication of water bodies. Thus, there is great need for a sustainable use of P with specia...

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

    Osita Obineche Obiukwu


    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.

  5. Electric Conductivity of Phosphorus Nanowires

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


    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.

  6. Prebiotic phosphorus chemistry reconsidered

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


    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.

  7. Phosphorus Accumulating Organisms and Biogeochemical Hotspots

    Archibald, J.; Walter, M. T.


    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.

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


    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.

  9. Global phosphorus retention by river damming

    Maavara, Taylor; Parsons, Christopher T.; Ridenour, Christine; Stojanovic, Severin; Dürr, Hans H.; Powley, Helen R.; Van Cappellen, Philippe


    Phosphorus is an essential nutrient for life. Humans have massively altered the global phosphorus cycle by increasing loading to river systems through fertilizer use, soil erosion, and wastewater discharges. River damming interacts with anthropogenic phosphorus enrichment by trapping a fraction of the phosphorus in reservoir sediments. We estimate that in 2000, 12% of the global river phosphorus load was retained in dam reservoirs. This fraction could increase to 17% by 2030, because of the c...

  10. Assessing risk of non-compliance of phosphorus standards for lakes in England and Wales

    Duethmann, D.; Anthony, S.; Carvalho, L.; Spears, B.


    High population densities, use of inorganic fertilizer and intensive livestock agriculture have increased phosphorus loads to lakes, and accelerated eutrophication is a major pressure for many lakes. The EC Water Framework Directive (WFD) requires that good chemical and ecological quality is restored in all surface water bodies by 2015. Total phosphorus (TP) standards for lakes in England and Wales have been agreed recently, and our aim was to estimate what percentage of lakes in England and Wales is at risk of failing these standards. With measured lake phosphorus concentrations only being available for a small number of lakes, such an assessment had to be model based. The study also makes a source apportionment of phosphorus inputs into lakes. Phosphorus loads were estimated from a range of sources including agricultural loads, sewage effluents, septic tanks, diffuse urban sources, atmospheric deposition, groundwater and bank erosion. Lake phosphorus concentrations were predicted using the Vollenweider model, and the model framework was satisfactorily tested against available observed lake concentration data. Even though predictions for individual lakes remain uncertain, results for a population of lakes are considered as sufficiently robust. A scenario analysis was carried out to investigate to what extent reductions in phosphorus loads would increase the number of lakes achieving good ecological status in terms of TP standards. Applying the model to all lakes in England and Wales greater than 1 ha, it was calculated that under current conditions roughly two thirds of the lakes would fail the good ecological status with respect to phosphorus. According to our estimates, agricultural phosphorus loads represent the most frequent dominant source for the majority of catchments, but diffuse urban runoff also is important in many lakes. Sewage effluents are the most frequent dominant source for large lake catchments greater than 100 km². The evaluation in terms of

  11. Methylotrophic bacteria in sustainable agriculture.

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


    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

  12. The impact of agricultural soil erosion on biogeochemical cycling

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


    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...

  13. Total Phosphorus in Surface Water

    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...

  14. Determination of soil organic phosphorus exchange sensitivity

    Shand, Charles; Wendler, Renate; Lumsdon, David; Cooper, Pat; George, Timothy; Brown, Lawrie; Giles, Courtney; Stutter, Marc; Menezes-Blackburn, Daniel; Zhang, Hao; Wearing, Catherine; Haygarth, Philip; Blackwell, Martin; Darch, Tegan


    Soils contain both organic and inorganic phosphorus (P) species in varying proportions. Studies have shown that many soils contain substantial amounts of inositol hexaphosphate (IHP) and there is much interest worldwide in developing strategies to make some use of this recalcitrant resource for plant growth to reduce P fertilizer inputs. Little is known about the preference of ion exchange processes in the solubilisation of organic vs inorganic P forms in soils, an important first step in making P forms bioavailable. Although they do not possess biotic functions, resins provides a simple means to deplete P forms in soil allowing investigation of exchange selectivity between inorganic and organic P forms. The aim of our work was to determine new understanding of exchange selectivity in soils and provide insight into potential depletion and plant uptake of soil phosphorus, with emphasis on organic forms such as IHP. For our study we used a Cambisol sampled from an agricultural area (Tayport) near Dundee in Scotland. The soil had a high Olsen (0.5 M sodium bicarbonate at pH 8.5) extractable P status (84 mg P/kg) and P-31 nuclear magnetic resonance analysis of its NaOH/EDTA extract showed it contained a substantial proportion of IHP (21 % of total extractable P). For resin extraction we used anion exchange resin sheets (4.17 cm each side) in bicarbonate form to minimise pH related solubilisation effects. We used 3.5 g of soil in 75 ml of water and added 1, 2 or 3 resin squares. After equilibration the resin squares were removed and replaced with fresh resin squares a further 3 times. Phosphorus was recovered from the resin sheets by elution with 0.25 M sulphuric acid and analysed by inductively coupled plasma spectroscopy to determine total P, and colorimetrically with malachite green to determine inorganic P with the remainder assigned to organic P. The data showed that the resin preferentially removed inorganic P and even after four sequential extractions little or

  15. Phosphorus application strategies in potato

    Ekelöf, Joakim


    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 ...

  16. Expression of phosphate transporter in small intestine, kidney, and parotid salivary gland of cattle fed differing levels of phosphorus from wet distiller's grains

    Phosphorus (P) in the diets of animals in concentrated animal feeding operations (CAFOs) is of great importance with the increasing concern of environmental impact of animal agriculture. Excess phosphorus in diets of cattle is excreted in the manure and, if improperly managed, can be washed into loc...

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

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


    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

  18. International phosphorus workshop

    Kronvang, Brian; Rubæk, Gitte Holton; Heckrath, Goswin


    Received for publication February 9, 2009. Agriculture is a major source of P to the aquatic environment in many countries. Although efforts have been made to improve the P utilization in agricultural production, which is reflected in modestly declining P surpluses in many countries, increasing......) functioning of riparian buffers; (iv) ecological responses to P loadings and impacts of climate change. Each of these four topics interacts with each other as well as with the four tiers of the P Transfer Continuum (Source, Mobilization, Transport, and Ecological Effects). In this review paper we highlight...... the main outcomes of the workshop and the special collection of eight papers. Moreover, we identify the main gaps in our knowledge and future research directions on P, which are linked to important issues such as addressing scale effects, improved P models with the ability to quantify uncertainty, the...

  19. Bacteria as transporters of phosphorus through soil

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


    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 to the...

  20. Natural Phosphorus Sources for the Pacific Northwest

    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...

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

    Prata Fábio


    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.

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

    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)

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

    Sutphin, Michael D.


    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.

  4. Edge phonons in black phosphorus.

    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


    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

  5. Electric Conductivity of Phosphorus Nanowires

    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)

  6. Interactions between exogenous rare earth elements and phosphorus leaching in packed soil columns

    Rare earth elements (REEs) increasingly used in agriculture as an amendment for crop growth may help to lessen environmental losses of phosphorus (P) from heavily fertilized soils. The vertical transport characteristics of P and REEs, lanthanum (La), neodymium (Nd), samarium (Sm), and cerium (Ce), w...

  7. Redox chemistry in the phosphorus biogeochemical cycle

    Pasek, Matthew A.; Sampson, Jacqueline M.; Atlas, Zachary


    Phosphorus is an important nutrient for living organisms. Phosphorus is generally considered to bear a 5+ oxidation state, but several lower redox states have been reported, including the toxic gas phosphine. We show here that the lower redox states of phosphorus are common in Florida water samples, and that based on the global concentration of phosphine, we might expect to see 5−15% of all dissolved phosphorus in a lower redox state.

  8. Phosphorus in Phoenix: a budget and spatial representation of phosphorus in an urban ecosystem.

    Metson, Geneviève S; Hale, Rebecca L; Iwaniec, David M; Cook, Elizabeth M; Corman, Jessica R; Galletti, Christopher S; Childers, Daniel L


    As urban environments dominate the landscape, we need to examine how limiting nutrients such as phosphorus (P) cycle in these novel ecosystems. Sustainable management of P resources is necessary to ensure global food security and to minimize freshwater pollution. We used a spatially explicit budget to quantify the pools and fluxes of P in the Greater Phoenix Area in Arizona, USA, using the boundaries of the Central Arizona-Phoenix Long-Term Ecological Research site. Inputs were dominated by direct imports of food and fertilizer for local agriculture, while most outputs were small, including water, crops, and material destined for recycling. Internally, fluxes were dominated by transfers of food and feed from local agriculture and the recycling of human and animal excretion. Spatial correction of P dynamics across the city showed that human density and associated infrastructure, especially asphalt, dominated the distribution of P pools across the landscape. Phosphorus fluxes were dominated by agricultural production, with agricultural soils accumulating P. Human features (infrastructure, technology, and waste management decisions) and biophysical characteristics (soil properties, water fluxes, and storage) mediated P dynamics in Phoenix. P cycling was most notably affected by water management practices that conserve and recycle water, preventing the loss of waterborne P from the ecosystem. P is not intentionally managed, and as a result, changes in land use and demographics, particularly increased urbanization and declining agriculture, may lead to increased losses of P from this system. We suggest that city managers should minimize cross-boundary fluxes of P to the city. Reduced P fluxes may be accomplished through more efficient recycling of waste, therefore decreasing dependence on external nonrenewable P resources and minimizing aquatic pollution. Our spatial approach and consideration of both pools and fluxes across a heterogeneous urban ecosystem increases the

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

    Bussi, Gianbattista; Whitehead, Paul; Dadson, Simon


    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.

  10. Agricultural Geophysics

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  11. Utilization of radioisotopes in the agriculture

    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.)

  12. The Use of Interactive Computer Animations Based on POE as a Presentation Tool in Primary Science Teaching

    Akpinar, Ercan


    This study investigates the effects of using interactive computer animations based on predict-observe-explain (POE) as a presentation tool on primary school students' understanding of the static electricity concepts. A quasi-experimental pre-test/post-test control group design was utilized in this study. The experiment group consisted of 30…

  13. Dynamic phosphorus budget for lake-watershed ecosystems

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


    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.


    Phosphorus (P) is a primary nutrient necessary for plant growth. When soil P level is below what is needed for plant needs, P is supplied to the soil by the addition of P fertilizer or organic residuals (i.e., manure). Because of P fertilizer use in the past few decades or application of manure, a g...

  15. Black phosphorus nonvolatile transistor memory.

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


    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 (10(4) s), and cyclic endurance (1000 cycles). PMID:27074903

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

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


    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

  17. Phosphorus use efficiency of the gum arabi tree (Acacia senegal (L) Willd) in Sudan

    This study was conducted to identify gum arabic tree (Acacia senegal L. Willd) provenances with high efficiency for phosphorus uptake and use. Thirteen provenances were collected from different habitats with the gum belt of the Sudan. A preliminary trial was conducted during the period 1989-1992 at the Gezira Agricultural Research Station in Wad Medani. This study revealed that there are clear genotypic differences in phosphorus use efficiency, nitrogen yield and dry matter production. All the provenances tested also exhibited a high ability for survival under the dry climatic conditions as prevailing in the gum belt of Sudan. Based on differences in phosphorus use efficiency observed in the preliminary study, 4 provenances were selected for a detailed study. Provenance 11 and 2 represented the highly efficient group, provenance 7 the moderately efficient group and provenance 13 the low efficient group. The detailed study revealed that provenance 11 is superior to all others in terms of biomass production as well as in phosphorus use efficiency. Although the ability to take up phosphorus was low, this was compensated by having a high root length density enabling the tree to take up a quantity of phosphorus similar to that taken up by other provenances. The high ability to convert the absorbed phosphorus into a greater quantity of dry matter made this provenance the best in phosphorus use efficiency. These results suggest that provenance 11 may be a suitable candidate to be introduced into the gum belt of Sudan in support of its rehabilitation programme. (author). 13 refs, 4 figs, 5 tabs

  18. Agricultural sector

    The applications of nuclear technology in agriculture sector cover the use of the technology at every aspects of agricultural activity, starting from the seed to harvesting as well as the management of plantations itself. In this sector, a total of 55 entities comprising 17 public agencies and 38 private companies were selected for the study. Almost all, 91 % of them are located in Peninsular Malaysia; the rest operates in Sabah and Sarawak. The findings of the study in the public agencies and private companies are presented in the next sections. (author)

  19. Agricultural methanization

    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

  20. Farmland Runoff of Nitrogen and Phosphorus in Songhuajiang Watershed

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


    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

  1. Phosphorus doping a semiconductor particle

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


    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.

  2. Black phosphorus nonvolatile transistor memory

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


    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

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

    Etheridge, Alexandra B.


    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


    Walter B. Gordon; Larry Murphy; Pawel Wiatrak


    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...

  5. Phosphorus requirement in laying hens

    Lambert, W; Krimpen, van, M.M.; Star, L.


    It was hypothesized that P supply by feed in alternative housing systems can be lowered without negative effects on bone quality and production performance. Therefore, the objectives of the current study were 1) to update the retainable phosphorus (rP) needs of two modern laying hen breeds from 36 to 90 weeks of age housed in an aviary system, 2) to investigate the influence of dietary rP levels on Ca and P content in eggs, manure, carcasses and bones.

  6. Abiotic and prebiotic phosphorus chemistry

    Micheletti, Gabriele


    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...

  7. Phosphorus Management and Water Quality Problems in Grazingland Ecosystems

    Maria L. Silveira


    Full Text Available Phosphorus management in grazingland ecosystems represents a major challenge of agronomic and environmental importance. Because of the extensive acreage occupied by grazinglands, decisions concerning pasture fertilization and nutrient management in forage-based livestock systems are crucial to both farmers and regulatory agencies. The purpose of this paper is to provide an overview of the literature relevant to pasture P fertilization and the potential impacts on water quality. There continue to be uncertainties regarding interrelationships between pasture management and water quality issues. Despite the extensive body of literature on nutrient transport from grazinglands, limited information is available on the relationships between land use, transport potential, water management, and climatic conditions affecting nutrient losses at a watershed scale. As agriculture continues to modernize and intensify, public concerns about the impacts of plant nutrients on environmental quality will likely increase. Managing water quality protection and profitable agriculture will be a major challenge for the next generations.

  8. Modeling Phosphorus Transport and Cycling in the Greater Everglades Ecosystem

    James, A. I.; Grace, K. A.; Jawitz, J. W.; Muller, S.; Munoz-Carpena, R.; Flaig, E. G.


    A solute transport model was used to predict phosphorus mobility in the northern Everglades. Over the past several decades, agricultural drainage waters discharged into the northern Everglades, have been enriched in phosphorus (P) relative to the historic rainfall-driven inputs. While methods of reducing total P concentrations in the discharge water have been actively pursued through implementation of agricultural Best Management Practices (BMPs), a major parallel effort has focused on the construction of a network of constructed wetlands for P removal before these waters enter the Everglades. This study describes the development of a water quality model for P transport and cycling and its application to a large constructed wetland: Stormwater Treatment Area 1 West (STA 1W), located southeast of Lake Okeechobee on the eastern perimeter of the Everglades Agricultural Area (EAA). In STA 1W agricultural nutrients such as phosphorus (P) are removed from EAA runoff before entering the adjacent Water Conservation Areas (WCAs) and the Everglades. STA 1W is divided by levees into 4 cells, which are flooded for most of the year; thus the dominant mechanism for flow and transport is overland flow. P is removed either through deposition into sediments or is taken up by plants; in either case the soils end up being significantly enriched in P. The model has been applied and calibrated to several years of water quality data from Cell 4 within STA 1W. Most existing P models have been applied to agricultural/upland systems, with only a few relevant to treatment wetlands such as STA 1W. To ensure sufficient flexibility in selecting appropriate system components and reactions, the model has been designed to incorporate a wide range of user-selectable mechanisms for P uptake and release parameters between soils and inflowing water. The model can track a large number of mobile and nonmobile components and utilizes a Godunov-style operator-splitting technique for the transported

  9. Phytoextraction of excess soil phosphorus

    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:


    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.

  10. The Galactic evolution of phosphorus

    Caffau, E; Faraggiana, R; Steffen, M


    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...

  11. Potential Phosphorus Mobilisation in Peat Soils

    Forsmann, Ditte M.; Kjærgaard, Charlotte


    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...

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

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


    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…

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

    Cordell, Dana


    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...

  14. Agricultural radioecology

    The problem of radioactive pollution of ecosystems is discussed. The total deposition of 90Sr and 137Cs after the nuclear experiments in 1945-1963 and the contamination rate of main foodstuffs are assessed. Data about radionuclide dynamics in soil, raw materials, forage, milk, milk products and wheat after the Chernobyl accident are presented for various regions of Bulgaria and are compared with the total fallout contamination. The trends in milk and forage contamination for some regions are discussed. Quantitative radiochemical methods for determination of 90Sr and 137Cs are discussed. Migration of 135Cs, 90Sr and 131J is followed in soil, forage, animal organism and human food chains respectively and ways of decontamination are discussed. Radiation effects on biogeocenoses are described. The problem of agriculture management under the conditions of durable soil contamination after nuclear accidents is considered. Recommendations for monitoring and protection of agricultural personnel are presented. 53 refs., 31 tabs., 93 figs

  15. Kinetic behaviour of the adsorption and desorption of phosphorus-32 on aluminium hydroxide

    Great amount of phosphate fertilizers are used in agriculture. Soil fertility have been studied using fertilizer labelled with phosphorus 32 to improve agronomic practices by increasing the efficient use of phosphate fertilizer. Previous research work have been published suggesting the potential use of kinetics parameters to characterize phosphorus in soil and to diagnosis the phosphate level. In this work the kinetic behaviour of the absorption and desorption of phosphorus-32 on a synthetic aluminium hydroxide was studied attempting to detect the formation of a precipitated phase on the hydroxide surface. The kinetic data for adsorption was adjusted with the Elovich and Fardeau equations for isotopic exchange. It was verified a change in the kinetic behaviour when the surface was approximately 80% saturated. This change suggested the formation of a precipitate. The kinetic data for desorption was fitted with the Fardeau equation, and it was verified the desorption kinetics slower than the desorption. (B.C.A.). 40 refs, 17 figs, 5 tabs

  16. Alternative Agriculture


    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

  17. Phosphorus removal in aerated stirred tank reactor

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


    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.

  18. Energy and phosphorus recovery from black water.

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


    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, is more than sufficient for anaerobic treatment, nitrogen removal and phosphorus recovery. The phosphorus balance of an upflow anaerobic sludge blanket reactor treating concentrated BW showed a phosphorus conservation of 61% in the anaerobic effluent. Precipitation of phosphate as struvite from this stream resulted in a recovery of 0.22 kgP/p/y, representing 10% of the artificial phosphorus fertiliser production in the world. The remaining part of the phosphorus ended up in the anaerobic sludge, mainly due to precipitation (39%). Low dilution and a high pH favour the accumulation of phosphorus in the anaerobic sludge and this sludge could be used as a phosphorus-enriched organic fertiliser, provided that it is safe regarding heavy metals, pathogens and micro-pollutants. PMID:22049776

  19. Agricultural problems

    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

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

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


    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

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

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


    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

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

    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.


    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

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

    Hansen, Line Block; 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 characterized by the presence of large...... 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....... 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...

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

    Hansen, Line Block; Gårn Hansen, Lars


    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...... 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....... 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...

  5. Agricultural ponds support amphibian populations

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


    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

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

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


    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 ??mol??g-1. Deposition is highly focused, with ???0% 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.

  7. Phosphorus diffusion in polycrystalline silicon

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


    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.

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

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


    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...... toxicological issues, 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....

  9. Phosphorus binding by aluminium in sediment: a tool for restoring water quality in the Baltic Sea and other brackish surface waters

    Huser, Brian


    Lake and sea sediments act as stores for historical inputs of pollutants from both direct and diffuse sources including urbanization, agriculture, municipal and indus- trial waste waters, among others. Historical accumulation in sediments can provide a continual source of phosphorus to the water column for decades or longer after external sources have been controlled. Addition of metal salts, e.g. aluminium salts, can permanently bind this excess phosphorus in the sediment, thereby reducing i...

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

    Anderson, Daniel; Hilbert, Kent; Lewis, David


    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.

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

    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 ...

  12. Long-term effects of biosolid-amended soils on phosphorus, copper, manganese and zinc uptake by wheat

    Biosolids have been applied to agricultural land for many years as a source of plant nutrients. There are growing concerns of residual phosphorus and metals from long-term biosolids amended fields and their potential impact on the environment. Objectives of this study were to determine, i) phosphor...

  13. Energy and phosphorus recovery from black water

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


    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,

  14. Department of Agriculture

    ... Safety Forestry Housing Assistance Laws and Regulations Organic Agriculture Outreach Plant Health Research and Science Rural and ... Agricultural Research Agricultural Statistics Economic Research Food and Agriculture Research OPEDA Scholarship Program MARKETING AND TRADE Exporting ...

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

    Heckenmüller, Markus; Narita, Daiju; Klepper, Gernot


    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...

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

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


    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...

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

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


    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...

  18. Electrodialytic extraction of phosphorus from ash of low-temperature gasification of sewage sludge

    Viader, Raimon Parés; Jensen, Pernille Erland; Ottosen, Lisbeth M.; Hauggaard-Nielsen, Henrik; Ahrenfeldt, Jesper


    100-400 years [1]. In 2012 EU imported 88% of the phosphate rock consumed. Since only about one fourth of the P applied to agricultural fields is actually recycled today [2], innovative recycling and re-use concepts need to be developed and adopted. Low-temperature gasification allows an energy...... process. However, major concerns are its heavy metal content and the low plant availability of P; hence, a separation of phosphorus from the bulk bioashes and heavy metals would be beneficial....

  19. Phosphorus fractions in valle del cauca soils under different coffee cropping systems

    Mejía Umaña, Diana Milena; Ángel Sánchez, Diego Iván; Menjivar Flores, Juan Carlos


    This study was conducted in the coffee growing zone of Valle del Cauca (Colombia) to evaluate the effect of planting coffee under different cropping systems: organic, conventional and organic-mineral, on soil phosphorus (P) fractions.  Adapted sequential fractionation methodology was done by the International Center of Tropical Agriculture.  The statistical analysis consisted of a Complete Randomized Block Design under a split plot arrangement with three treatments and three replications.  Th...

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

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


    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...


    Ancev, Tihomir; Stoecker, Arthur L.; Daniel E. Storm


    Phosphorus pollution from excessive litter application and municipal discharges causes eutorphication of lakes in the Eucha-Spavinaw watershed in eastern Oklahoma and western Arkansas. Consequent algae blooms impair the taste of drinking water supply drawn from the watershed and reduce the recreational values of the lakes. The paper shows how GIS data based biophysical modeling can be used to derive spatially optimal, least-cost allocation of agricultural management practices to be combined w...

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

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


    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.

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

    B. O. L. Demars


    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.

  4. Phosphorus metabolism and estimation of phosphorus requirements for sheep

    The main objective of the present work was to determine the effects of different dietary phosphorus (P) levels on endogenous faecal loss and to estimate the minimum daily requirement of P for sheep. The study was conducted with 24 Suffolk sheep which received a basic diet consisting of a hay-concentrate mixture. The treatment consisted of different amounts of bone meal, added to the basic diet, so as to obtain supplementary P levels of 0, 2 and 3 g/day. Twenty-one days after the introduction of the experimental diet, 7.4 MBq radioactive P (32 P) was injected in the left jugular vein of each sheep and blood, feces and urine were collected daily for 8 days at 24-hour intervals. The samples were analysed for inorganic P and for radioactive specific activities. Mean endogenous faecal losses of P were 10.00, 31.79, 39.35 and 38.06 mg/kg live weight (LW) per day in sheep supplemented with 0, 1, 2 and 3 g respectively. A positive linear relation ship was observed between endogenous faecal loss and consumed P, indicating that this loss was linked to dietary P. Total P excretion in the faeces, as well as P absorption, retention urinary excretion and salivary secretion were also directly related to P intake, as part of the mechanism of homeostatic control of organism animal. The minimum endogenous faecal loss for zero P intake, calculated by interpolation, was 8.27 mg/kg LW per day, and for zero balance, the calculated phosphorus consumption was 21.36 mg/kg LW per day. (author)

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

    Wang, J.; Pant, H. K.


    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.

  6. Agriculture ideas and modernization of agriculture

    Li Kangmin


    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...

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

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


    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 (ahundant 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 hiomass from low water period to ahundant water period. Mass cohcentrations of several forms of phosphorus were all the highest in the rivers impacted hy sanitary wastewater, hut sanitary wastewater's self-purification capabity from the upper reaches of river to lower reaches of river was the hest, 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

  8. Determining Phosphorus-sediment Interactions in a Groundwater-fed River through In Situ Measurement

    Mullinger, N. J.; Heathwaite, L.; Zhang, H.; Keenan, P. O.


    In stream processing is potentially important in the regulation and availability of nutrients to riverine flora and also in attenuating point and non-point source inputs to rivers, such as wastewater outflows and agricultural runoff. Phosphorus is an important macronutrient and often cited as a limiting factor to plant and algal growth in freshwater systems. The particle-reactive nature of the orthophosphate anion means that river sediments can play an important role in phosphorus attenuation and availability in rivers. However, it is also known that plant root exudates can also affect the mobilisation of sediment adsorbed phosphorus. Results are presented from high resolution (centimetre) measurements of vertical riverbed pore water profiles at a field site in the River Leith, Cumbria, UK. The River Leith is a sub-catchment of the River Eden and is characterised by significant groundwater-surface water interactions at the monitoring site. In situ measurements of soluble reactive phosphorus (SRP) in riverbed pore waters were made using passive sampling diffusive gradient and diffusive equilibration in thin film (DGT and DET) probes. These probes allow in situ measurements of riverbed pore waters to be made to a depth of 30 cm below the riverbed at centimetre resolution. The resulting profiles provide information on the variability in phosphorus pore waters for vegetated and non-vegetated regions of the riverbed. The impact of vegetated root zones in riverbed sediments is poorly characterised for hyporheic exchanges. Comparison of the vertical profiles obtained by DGT and DET probes identifies the potential of sediments to act sources or sinks of in stream phosphorus. Simultaneous analysis for redox sensitive elements provides additional information on the redox status of riverbed sediments. Initial results show spatial and temporal variability of phosphorus in different sedimentary environments and also between vegetated and non-vegetated areas of the riverbed


    Walter B. Gordon


    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.

  10. Black phosphorus for future devices

    Meunier, Vincent

    Black phosphorus (or ``phosphorene'' at the monolayer limit) has attracted significant attention as an emerging 2D material due to its unique properties compared with well-explored graphene and transition metal dichalcogenides such as MoS2 and WSe2. In bulk form, this monoelemental layered structure is a highly anisotropic semiconductor with a bandgap of 0.3 eV which presents marked distinctions in optical and electronic properties depending on crystalline directions. In addition, black phosphorus possesses a high carrier mobility, making it promising for applications in high frequency electronics. A large number of characterization studies have been performed to understand the intrinsic properties of BP. Here I wil present a number of investigations where first-principles modelling was combined with scanning tunneling microscopy (STM), Raman spectroscopy, and transmission electron microscopy (TEM) to assist in the design of phosphorene-based devices. . I will provide an overview of these studies and position them in the context of the very active research devoted to this material. In particular, I will show how low-frequency Raman spectra provide a unique handle on the physics of multilayered systems and how BP's structural anisotropy weaves its way to its unusual polarization dependent Raman signature. Finally, I will show recent progress where nanopores, nanobridges, and nanogaps have been sculpted directly from a few-layer BP sample using a TEM, and indicate the potential use of these results on the creation of phosphorene-based nanoelectronics. I wil conclude this talk with a critical look at the issues of phosphorene stability under ambient conditions. Collaborators on this research include: Liangbo Liang, Bobby G. Sumpter, Alex Puretzky, Minghu Pan, (Oak Ridge National Laboratory), Marija Drndic (University of Pennsylvania), Mildred Dresselhaus, Xi-Ling, Shengxi Huang (Massachusetts Institute of Technology).