FREE ELECTRONIC LIBRARY - Dissertations, online materials

Pages:     | 1 |   ...   | 57 | 58 || 60 | 61 |   ...   | 92 |

«International 17 Workshop th Nitrogen The was jointly organised by Teagasc and AFBI Printed by Print Depot Suggested citation Authors, 2012. Title ...»

-- [ Page 59 ] --

References Bouwman, A.F., Boumans, L.J.M. and Batjes, N.H. 2002. Emissions of N2O and NO from fertilized fields: summary of available measurement data. Global Biogeochemical Cycles 16, 1080, doi:10.1029/2001GB001812.

IPCC (1996) Intergovernmental Panel on Climate Change. The science of climate change. In: Houghton JT, Meira Filho LG, Callander, BA, Harris, N, Kattenberg, A. and Maskell, K (eds) Climate change 1995. Cambridge University Press, Cambridge, p 22.

Linzmeier, W., Gutser, R. and Schmidthalter, U. 2001. Nitrous oxide emission from soils and from a 15N-labelled fertilizer with the new nitrification inhibitor 3,4-dimethyl pyrazole phosphate (DMPP). Biology and Fertility Soils 34, 103-108.

Menéndez S., Merino P., Pinto M., González-Mura C. and Estavillo J.M. 2006. 3,4-Dimethylpyrazol phosphate effect on nitrous oxide, nitric oxide, ammonia, and carbon dioxide emissions from grasslands. Journal of Environmental Quality 35, 973-981.

Menéndez S., López-Bellido R.J., Benítez-Vega J., González-Murua C., López-Bellido L. and Estavillo J.M. 2008.

Long-term effect of tillage, crop rotation and N fertilization to wheat on gaseous emissions under rainfed Mediterranean conditions. European Journal of Agronomy 28, 559-569.

Ortiz-Monasterio, J.L., Matson, P.A., Panek, J. and Naylor, R.L. 1996. Nitrogen fertiliser management of N2O and NO emissions in Mexican irrigated wheat. In: Transactions Ninth Nitrogen Workshop. Braunschweig, September, pp. 531Pereira, J., Fangueiro, D., Chadwick, D., Misselbrook, T.H., Coutinho, J. and Trindade, H. 2010. Effect of cattle slurry pre-treatment by separation and addition of nitrification inhibitors on gaseous emissions and N dynamics: A laboratory study. Chemosphere 79(6), 620-627.

Weiske, A., Benckiser, G., Herbert, T., Ottow, J.C.G. 2001. Influence of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) in comparison to dicyandiamide (DCD) on nitrous oxide emissions, carbon dioxide fluxes and methane oxidation during 3 years or repeated application in field experiments. Biology & Fertility of Soils 34, 109-117.

–  –  –

Effect of nitrogen fertilization on nitrate leaching in relation to grain yield response in Sweden Delin, S.a, Stenberg, M.a a Department of Soil and Environment, Swedish University of Agricultural Sciences, Skara, Sweden

1. Background & Objectives Swedish farmers are encouraged to fertilize no more than the economic optimum in order to minimize nitrogen (N) leaching. Site-specific fertilization with respect to variation within fields could reduce N leaching further, but the effect would depend on the difference in leaching between fertilization above and below the optimum. To what extent the N leaching is affected above and below economical optimum varies in literature. According to Petersen and Djurhuus (2004) leaching is significantly increased already at rates below fertilizer recommendations, whereas Lord and Mitchell (1998) present data where leaching is affected only at rates above economical optimum. The objective of our study was to compare the effect of N fertilization on nitrate N leaching depending on grain yield response, i.e. above and below economical optimum in a cereal crop under Swedish weather conditions.

2. Materials & Methods Nitrate N leaching in response to different fertilizer N doses was investigated at two sites in southwest Sweden. Five field trials in spring oat were conducted in 2007, 2008 and 2009 on a loamy sand and in 2009 and 2010 on a silty clay. Each trial had five or seven N fertilization treatments (0of recommended rate of ammonium nitrate) distributed randomly within four blocks. The subsequent crops (year two) were winter wheat or spring barley, which received normal fertilization rates (100 kg N ha-1 in spring barley and 150 kg N ha-1 in winter wheat) in all treatments. On the loamy sand, soil water was sampled using ceramic suction cups (Djurhuus, 1990) installed in triplicate at 80 cm depth in each plot. On the clay soil, plots with separate drainage systems at 1 m depth were used. Each plot had a separate collector for drainage water comprising a measuring station where the amount of drainage water from each plot was measured with a wagging vessel, and flow-proportional water samples were collected from each plot automatically. Sampling from both systems was carried out bi-weekly during periods with water flow through drainage, from the time of fertilization (April) until June the following year. The samples from suction cups were analyzed for nitrate and from the separate drainage system for both total N and nitrate N. Nitrate N leaching was determined from nitrate concentrations in soil water and discharge, accounting for both direct and residual effects. Grain yield was measured plot-wise by combine harvester and reported at 85% dry matter. Grain yield was plotted against N fertilization rate and fitted second order polynomials were used to estimate economic optimum N fertilization rates, when price ratio of grain to fertilizer is 10:1. In order to compare the influence of fertilization on leaching above and below optimum, the deviation in leaching from that in the unfertilized treatment was plotted against the deviation in fertilization from economical optimum fertilization rate.

3. Results & Discussion On the sandy loam, the yield responded differently in different years, resulting in very different optimum N fertilisation rates (Figure 1A), ranging from 12 to 104 kg N ha-1. On the silty clay, yield response was better in 2009 resulting in a optimum N fertilization rate of 130 kg N ha-1 compared to 100 kg N ha-1 in 2010 (Figure 1B). Nitrate leaching was not significantly affected below economical optimum, i.e. as long as each kg N ha-1 of additional fertilisation led to at least 10 kg ha


Nitrogen Workshop 2012

increase in grain yield (Figures 1C and 1D). However, at larger N rates nitrate-N leaching increased exponentially at about 1-2 kg N ha-1 for every 5 kg of extra N fertilizer applied at the loamy sand (Figure 1C) and 0.5 kg N ha-1 leached for every 5 kg of extra N fertilizer applied at the silty clay (Figure 1D).

–  –  –

4. Conclusion The difference in effect on leaching above and below economical optimum indicates that sitespecific N fertilization has the potential to reduce N leaching as long as fertilization will be kept at or below economic optimum at a larger area of the land.

References Djurhuus, J. 1990. Sammenligning af nitrat i jordvand udtaget med sugkopper og ekstrahert fra jordprøver.

Landbrugsministeriet, Statens Planteavlsforsøg, Særtryk af Tidsskrift for Planteavl 94, 487-495.

Lord, I.E. and Mitchell, R.D.J. 1998. Effect of nitrogen inputs to cereals on nitrate leaching from sandy soils. Soil Use and Management 14, 78-83.

Peterssen, J. and Djurhuus, J. 2004. Sammenhæng mellem tilførsel, udvaskning og optagelse af kvælstof i handelsgødede, kornrige sædskifter. DJF rapport markbrug nr. 102, 55 s.

Nitrogen Workshop 2012

Effect of non-fertilized winter grazing dairy production on soil N balances and soil N dynamics in a clay-loam soil Necpalova, M.a,b, Phelan, P.a,b, Casey, I.b, Humphreys, J.a a Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Co Cork, Rep of Ireland b Department of Chemical and Life Sciences, Waterford Institute of Technology Cork Road, Waterford, Rep of Ireland

1. Background & Objectives Soil surface nitrogen (N) balances and soil soluble N pools are often analysed to evaluate nutrient management practices on the soil surface. Winter grazing under moist temperate conditions has a high potential to affect soil N dynamics. The objective of this study was to investigate the effect of non-fertilized winter grazing dairy production on soil surface N balances and soil soluble N dynamics in a clay loam soil profile on a dairy farm in south Ireland over two production years.

2. Material & Methods The systems were: (i) ES-100N–Early spring calving with 100 kg ha-1 of fertilizer N (Feb, March, Apr):grazed from Feb to Nov and stocked at 2.1 cows ha-1; (ii) ES-0N–Early spring calving without fertilizer N: grazed from Feb to Nov and stocked at 1.6 cows ha-1; (iii) LS-0N–Late spring calving without fertilizer N: stocked at 1.7 cows ha-1 between calving and 1st Sept and then 1.3 cows ha-1 until the end of Jan since extra 3.7 ha was added to the system area. Each system consisted of six paddocks (1 ha) on a clay-loam soil (28% clay).The excreta from housed animals were collected in a single tank. Soil surface N balances for each paddock and each year were calculated in accordance with the methodology of the Organisation for Economic Co-operation and Development (OECD, 2001). Inputs included N entering the soil through the soil surface as mineral fertilizer N, slurry, animal excreta, atmospheric deposition and white clover biological N fixation (BNF).

Outputs consisted of N leaving the soil as harvested and grazed herbage. The soil surface N surplus was calculated as the difference between N inputs and outputs. Nitrogen fluxes were quantified and expressed on an annual basis. The quantities of N excreted by animals were calculated as the difference between N intake in feeds and N output in milk and calves, accounting for live weight change (Powell et al., 2006). Nitrogen excreted in each paddock was estimated according to the number of grazing days in the particular paddock. Atmospheric deposition was measured in situ.

Biological N fixation was estimated using an empirical model (Humphreys et al., 2008), based on herbage yields and white clover content. Nitrogen removed in herbage was estimated from pregrazing and pre-harvest herbage cuts (Humphreys et al., 2008) and herbage N content. Soil samples were taken from four paddocks per system eight times during the study period. At each sampling, 15 cores per paddock were taken using a hydraulic auger. Each core was subdivided into depths: 0 to 0.3 m, 0.3 to 0.6 m and 0.6 to 0.9 m and bulked to a composite sample at each depth within each paddock. Immediately after sampling, extracts were obtained by shaking in 2M KCl continuously for three hours at solution ratio of 2:1 (400ml:200 g, ratio v/w). Ammonium N and total oxidised N (TON) were determined using Aquakem 600 Discrete analyser. Total soluble nitrogen (TSN) was measured using a Shimadzu TOC-VCPH analyzer. Soluble organic N (SON) was calculated as the difference between TSN and inorganic N (TON+Ammonium N). Soil bulk density (BD) was measured as described by Blake and Hartge (1986). The results were expressed on an area basis using soil BD data for each depth. The experimental unit of the balances was a single paddock. The N flows were subjected to ANOVA (SAS Institute, 2009) examining the effects of the system, year and their interaction. Soil results were analysed as a repeated measure investigating the effect of the system, sampling depth and date, and their interactions. Simple linear regression was used to identify parameters that influenced soil N content.

Nitrogen Workshop 2012

3. Results & Discussion Soil surface balances for the systems are presented in Table 1. Linear regression revealed a positive correlation between total N inputs and N uptake by herbage (r2=0.30, P0.05) and between total N inputs and TSN (r2=0.43, P0.05). Total soluble N was also correlated with N surplus (r2=0.36, P0.05). All soluble N species decreased with sampling depth (P0.0001) and exhibited high temporal variation (P0.0001). Soluble inorganic N content at each sampling depth (0.9m) was not significantly affected by system operated on the soil surface. However, SON was influenced by system and sampling date interaction down to 0.6 m (P0.05). In all systems, TON at each sampling depth increased between March and August and then decreased during winter months due to N leaching. Ammonium N and SON were not as dynamic as TON and both of them displayed a similar seasonal pattern under all systems. Ammonium N (r2=0.72, P0.00001) and SON (r2=0.38, P0.0001) were positively related to gravimetric soil moisture content. In contrary, TON content was negatively related to effective rainfall (r2=0.35, P0.0001) and positively related to soil temperature (r2=0.47, P0.0001). This signifies its dependence on microbial activity and biochemical processes, and also its susceptibility to leaching during winter.

–  –  –

4. Conclusion The non-fertilized winter grazing dairy production system operated on a heavy textured clay loam soil did not affect annual soil surface N surplus and soil soluble N dynamics in the soil profile compared to the other systems. Seasonal changes in soluble N pools were driven by soil moisture content and soil temperature, which are the most important factors controlling microbial activity and biochemical processes.

Acknowledgement This study was funded by the Department of Agriculture, Fisheries and Food (RSF07-511) References Blake G.R. and Hartge K.H. 1986. Bulk Density. Agronomy 9, 363-375 Humphreys J. O’Connell, K. and Casey I.A. 2008. Nitrogen flows and balances in four grassland-based systems of dairy production on a clay-loam soil in a moist maritime environment. Grass and Forage Science 63, 467-480.

OECD (2001) Methods and Results. In: Environmental Indicators for Agriculture, vol. 3. Organisation for Economic Co-operation and Development, Paris, France.

Powell, J.M., Wattiaux, M.A., Broderick, G.A., Moreira, V.R. and Casler, M.D. 2006. Dairy diet impacts on fecal chemical properties and nitrogen cycling in soils. Soil Science Society of America Journal 70, 786–794.

Nitrogen Workshop 2012

Effect of non-fertilized winter grazing dairy production system based on a clay-loam soil on N leaching to groundwater Necpalova, M.a,b, Fenton, O.c, Casey, I.b, Humphreys, J.a a Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Co Cork, Rep of Ireland b Department of Chemical and Life Sciences, Waterford Institute of Technology Cork Road, Waterford, Rep of Ireland c Environmental Research Centre, Teagasc, Johnstown Castle, Co. Wexford, Rep of Ireland

Pages:     | 1 |   ...   | 57 | 58 || 60 | 61 |   ...   | 92 |

Similar works:

«2014 ASSEMBLY PROGRAM New Version All speakers and panelists confirmed. * Marked are invited. Timing of some sessions might change. THURSDAY, OCTOBER 30 13:00–18:00 REGISTRATION Location: Harpa 18:00–20:00 WELCOME RECEPTION Location: Reykjavik Art Museum, in the Harbour House _ FRIDAY, OCTOBER 31 – PLENARY SESSIONS 06:30–08:15 NETWORKING BREAKFAST AT HOTELS 07:30–17:00 REGISTRATION Location: Harpa 08:00–08:30 COFFEE SOCIAL Location: Harpa, Second Level 1 08:30–10:30 PLENARY...»

«CSRS Sistema de Retiro del Servicio Civil Beneficios de sobreviviente para los hijos Este folleto contesta las preguntas más comunes sobre: • Los hijos menores de los empleados o retirados fallecidos • Los estudiantes y el personal escolar • Los tutores de los niños incapacitados _ Oficina de Administración de Personal Federal (OPM) Servicio de Retiro y Seguro RI 25-27SP Revisado en agosto de 1999. No debe usarse la edición previa Disponemos de información sobre el retiro en la...»

«SORCERER INSTALLATION AND OPERATION By N0SYA December 6th, 2013 1 Preface This paper is intended to provide information on the installation and use of Sorcerer, a software multimode decoder. It was written following the theory that certain aspects of the tool such as features, optional settings, and tuning routines are the functional equivalent of those found in other decoding tools. More or less it's just those things I have noticed in the tool so far and would like to point them out for those...»

«gregory r a ba s s a’ s v ie w s on tr a ns L at ion* pe rs pectiva s de gregory r a ba s s a s obr e L a tr a d ucc ión Sergio Bolaños Cuéllar** Universidad Nacional de Colombia Artículo de investigación científica. Recibido 7-05-2011, aceptado: 10-06-2011 * Este artículo surgió del proyecto Teorías Modernas de la Traducción: Estado de la Cuestión y Crítica, inscrito en el grupo de investigación LINGUAE: Comunicación, Bilingüismo y Traducción, dirigido por el autor. **...»

«Community Based Adaptation: Enhancing urban community resilience 10th International Conference 21-28 April 2016 Dhaka, Bangladesh Conference proceedings Edited by Hannah Reid, Mostarin Begum, Sarah Colenbrander, Alexina Jackson, LuiseKatharina Minna Alfreda Richter, Amyas Walji and Mathew Winters 0 Contents Background to the Conference Series CBA10 Programme Summary The CBA10 Youth Conference Session Summaries Inaugural Plenary session 1: Conference Opening and Welcome Speeches Plenary session...»

«3(3):467-474 SOUTHEASTERN NATURALIST 2004 Common, but Commonly Overlooked: Red-bellied Woodpeckers as Songbird Nest Predators KIKSTEN R. HAZLER’.*, DAWN E.W. DRUMTRA’, MATTUEW R. MARSHALL~, ROBERT J. COOPER’, AND PAUI. B. HAMEL~ Abstract Woodpeckers in North America are not widely recognized as nest predators. In this paper, we describe several eyewitness accounts of songbird nest predation by Red-bellied Woodpeckers (Melunerpes cardims), document evidence that songbirds recognize...»

«Public Document Pack Mr Richard Parry Jones, MA. Prif Weithredwr – Chief Executive CYNGOR SIR YNYS MÔN ISLE OF ANGLESEY COUNTY COUNCIL Swyddfeydd y Cyngor Council Offices LLANGEFNI Ynys Môn Anglesey LL77 7TW Ffôn / tel (01248) 752500 Ffacs / fax (01248) 750839 RHYBUDD 0 GYFARFOD NOTICE OF MEETING CYD-BWYLLGOR ANGHENION ADDYSGOL SPECIAL EDUCATIONAL NEEDS JOINT ARBENNIG (MÔN A GWYNEDD) COMMITTEE (ANGLESEY & GWYNEDD) DYDD MAWRTH, 10 RHAGFYR, 2013 am 10 TUESDAY, 10 DECEMBER 2013 at 10.00 am....»

«UNLV Theses/Dissertations/Professional Papers/Capstones 12-2013 Business Plan for a Korean Fine-dining restaurant in Las Vegas Jihoon Kim University of Nevada, Las Vegas Follow this and additional works at: http://digitalscholarship.unlv.edu/thesesdissertations Part of the Food and Beverage Management Commons Repository Citation Kim, Jihoon, Business Plan for a Korean Fine-dining restaurant in Las Vegas (2013). UNLV Theses/Dissertations/Professional Papers/ Capstones. Paper 2044. This...»

«Journal of Human Resource and Sustainability Studies, 2015, 3, 57-65 Published Online June 2015 in SciRes. http://www.scirp.org/journal/jhrss http://dx.doi.org/10.4236/jhrss.2015.32009 Differentiated Rewards as an Enticement to Display and Develop More Professionalism in Higher Professional Education —Perceptions of Justice among the Lecture Staff Jol Stoffers, Erik Canisius Research Centre of Employability, Zuyd University of Applied Sciences, Heerlen-Maastricht-Sittard, The Netherlands...»

«Reviews of ‘The Status Report’ “Not bad” John, London “Poncey” Nathan, Reading “Didn’t taste very nice” Bute the Cat “Didn’t taste very nice” Jamie, aged 6 months 1 2 THE STATUS REPORT Alex Frankel with drawings by the poet and his mother 3 First published in Great Britain 2002 by Affected Publishing Ltd., Maidenhead, Berkshire http://www.affectedpublishing.co.uk Printed in England by Biddles Ltd. Copyright © 2002 by Alex Frankel The author has asserted his moral rights...»

«A STUDY OF THE BACTERIA ASSOCIATED WITH THIRTY SPECIES OF INSECTS EDWARD A. STEINHAUS Department of Bacteriology, Ohio State University, Columbus, Ohio' Received for publication April 4, 1941 Although there are many scattered reports on the bacteria associated with insects, knowledge concerning the bacterial flora of insects in general is markedly scant. Since there are over 600,000 known species of insects, it is apparent that a considerable amount of work will be necessary before even a...»

«National Urban Livelihoods Mission Mission Document lR;eso t;rs Government of India Ministry of Housing & Urban Poverty Alleviation National Urban Livelihoods Mission Mission Document lR;eso t;rs Ministry of Housing & Urban Poverty Alleviation Government of India Ministry of Housing & Urban Poverty Alleviation lR;eso t;rs Contents Sl.No. Title Page No. 1. Introduction 5-6 2. Mission, Principles, Values, Strategy 7-9 3. NULM Mission Cities and Target Population 10 4. Social Mobilisation And...»

<<  HOME   |    CONTACTS
2016 www.dissertation.xlibx.info - Dissertations, online materials

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.