My research career has focussed on nutrient cycling in grassland soils and natural waters, with particular emphasis on losses of inorganic and organic forms of nitrogen and phosphorus, organic carbon, and their impact on the receiving environment. This research also includes the high temporal resolution measurement and modelling of biogeochemical data across a range of scales.
More recently my expertise includes mitigation options for the control of a range of diffuse agricultural pollutants using landscape structures such as buffer strips, managed ponds, ditches and permeable reactive barrier technologies.
Broad background in soil and environmental science with particular expertise and research interests in:
- Losses of inorganic and organic nutrients from agricultural soils.
- Landscape mitigation options for the control of agricultural pollutants.
- Free and combined amino acids in soil and soil waters.
- Pattern recognition and informatics techniques and procedures.
- High resolution monitoring of hydrology and chemistry in soils and rivers.
- Carbon cycling in natural waters using an in-situ UV sensor.
- Gaseous emission of nitrous oxide and di-nitrogen from soil.
- Design and development of novel soil incubation systems for the measurement of nitrous oxide and di-nitrogen.
- Optimisation of nutrients in soil-plant systems - Determining how phosphorus availability is regulated in soils (BBSRC funded).
- Impacts of different vegetation and its management in buffer strips on hydrology and water quality (SARIC, BBSRC funded).
- Work Package Leader on North Wyke Farm Platform (BBSRC funded).
- ANAEE (EU funded).
Previous Recent Projects:
- Phosphorus mobilisation with sediment and colloids through drained and undrained grassland (Defra PE0120).
- Biofilters for reducing air and water pollution: their potential and barriers to uptake (Defra ELWG06).
- Scoping the potential of farm ponds to provide environmental benefits (Defra ESO109).
Phone:+44 (0) 1837 883 500 ext: +44 1837 883533
Location:Rothamsted Research - North Wyke, Okehampton, Devon, EX20 2SB
- Complex spatial variation of environmental variables: sampling, prediction and interpretation
- Processes and mechanisms of the interactions between grasslands and water
- Modular approaches to the control of diffuse agricultural pollution: Buffer zones, bioreactor, ditches and ponds
- Infrastructure for analysis and experimentation on ecosystems - ANAEE
Yuan, H. M., M. Blackwell, S. Mcgrath, T. S. George, S. H. Granger, J. M. B. Hawkins, S. Dunham And J. B. Shen (2015). "Morphological responses of wheat (Triticum aestivum L.) roots to phosphorus supply in two contrasting soils." The Journal of Agricultural Science. First View Article: 1-11. http://dx.doi.org/10.1017/S0021859615000702
Darch, T., A. Carswell, M. S. A. Blackwell, J. M. B. Hawkins, P. M. Haygarth and D. Chadwick (2015). "Dissolved Phosphorus Retention in Buffer Strips: Influence of Slope and Soil Type." Journal of Environmental Quality 44(4): 1216-1224.
Darch, T., M. S. A. Blackwell, J. M. B. Hawkins, P. M. Haygarth and D. Chadwick (2014). "A Meta-Analysis of Organic and Inorganic Phosphorus in Organic Fertilizers, Soils, and Water: Implications for Water Quality." Critical Reviews in Environmental Science and Technology 44(19): 2172-2202.
Hawkins, J.M.B., Blackwell, M.S.A., Chadwick. D (2014) Modular approaches to the control of diffuse agricultural pollution: buffer zones, bioreactors, ditches and ponds. Defra Final Report (WQ0126).
Sandford, R. C., Hawkins, J. M. B., Bol, R. and Worsfold, P. J. (2013). Export of dissolved organic carbon and nitrate from grassland in winter using high temporal resolution, in situ UV sensing. The Science of the Total Environment 456-457, 384-391.
H.J.E. Rodda and J. Hawkins. (2012). Testing Greenfield run-off estimation techniques using high-resolution field observations. Journal of Flood Risk Management. 5, 4, 366–375.
Krueger, T., J. N. Quinton, J. Freer, C. J. A. Macleod, G. S. Bilotta, R. E. Brazier, J. M. B. Hawkins and P. M. Haygarth (2012). Comparing empirical models for sediment and phosphorus transfer from soils to water at field and catchment scale under data uncertainty. European Journal of Soil Science
Old, G. H., Naden, P. S., Granger, S. J., Bilotta, G. S., Brazier, R. E., Macleod, C. J. A., Krueger, T., Bol, R., Hawkins, J. M. B., Haygarth, P. and Freer, J. (2012). A novel application of natural fluorescence to understand the sources and transport pathways of pollutants from livestock farming in small headwater catchments. The Science of the Total Environment 417-418: 169-182.
Granger, S. J., Bol, R., Hawkins, J. M. B., White, S. M.,Naden, P. S., Old, G. H., Marsh, J. K., Bilotta, G. S., Brazier, R. E., Macleod, C. J. A. & Haygarth, P. M. (2011). Using artificial fluorescent particles as tracers of livestock wastes within an agricultural catchment. Science of the Total Environment 409, 1095-1103.
Granger, S.J., Hawkins, J. M. B., Bol, R., White, S. M., Naden, P., Old, G., Bilotta, G. S., Brazier,R. E., Macleod, C. J. A., and Haygarth, P. M. (2010) High temporal resolution monitoring of multiple pollutant responses in drainage from an intensively managed grassland catchment caused by a summer storm. Water, Air and Soil Pollution 205, 377-393.
Bilotta GS, Krueger T, Brazier RE, Butler P, Freer J, Hawkins JMB, Haygarth PM, Macleod CJA, Quinton JN. 2010. Assessing catchment-scale erosion and yields of suspended solids from improved temperate grassland. Journal of Environmental Monitoring 12, 3, 31-739.
Naden PS, Old GH, Eliot-Laize C, Granger SJ, Hawkins JMB, Bol R, Haygarth P. 2010. Assessment of natural fluorescence as a tracer of diffuse agricultural pollution from slurry spreading on intensely-farmed grasslands. Water Research 44: 1701-1712.
Cardenas, L.M., Bol, R., Scholefield, D., Chadwick, D., Butler, M., Hawkins, J.M.B., Vallejo, A., Meijide, A., Bergstermann, A., Neftel, A., Felber, A., Hirsch, P.R., Matthews, P., Gregory, A., Whalley, R., Misselbrook, T., Hatch, D.J., Well, R. (2010) Putting the pieces of the puzzle together: denitrification, what we know and what the gaps are. Geophysical Research Abstracts 12.
Milne AE, Macleod CJA, Haygarth PM, Hawkins JMB, Lark RM. 2009. The wavelet packet transform: A technique for investigating temporal variation of river water solutes. Journal of Hydrology 379: 1-19.
J.M.B. Hawkins, M.S.A. Blackwell, S. Granger, D. Chadwick, P. Haygarth, and R. Bol Modular approaches to the control of diffuse agricultural pollution: buffer zones, bioreactors, ditches and ponds, Geophysical Research Abstracts, Vol. 11, EGU2009-3100, 2009 EGU General Assembly 2009, Vienna, Austria. Oral presentation.
Bilotta GS, Brazier RE, Haygarth PM, Macleod CJA, Granger S, Hawkins J, Krueger T, Freer J, Quinton J. 2008. Mobilisation and transport of sediments, colloids and phosphorus from intensively managed grasslands. Multifunctional grasslands in a changing world, Volume 1: XXI International Grassland Congress and VIII International Rangeland Congress, Hohhot, China, 29 June-5 July 2008: 821.
S Granger, J Hawkins, and the GRASP Team. Exploring mobilisation and transport of diffuse substances using multiple sediment and colloid tracers applied to a temperate grassland catchment. Geophysical Research Abstracts, Vol. 11, EGU2009-13962, 2009, EGU General Assembly 2009, Vienna, Austria. Poster presentation
Naden, Pamela; Old, Gareth; Eliot-Laize, Caroline; Granger, Steve; Hawkins, Jane; Bol, Roland; Haygarth, Phil. Issues in the use of fluorescence spectroscopy to trace amd quantify agricultural pollution from both diffuse and point sources. AGU Chapman Conference on Organic Matter Fluorescence University of Birmingham, Edgbaston, Birmingham, UK 20�23 October 2008. Poster presentation.
Scholefield, D., Hawkins, J. M. B, Fish, R.D. and Turner, M. (2007) Biofilters for reducing air and water pollution: their potential and barriers to uptake. Defra Final Report (ELWG06).
Macleod, C. J. A., Bilotta, G. S., Bol, R., Brazier, R. E., Butler, P. J., Freer,J., Gimbert, L. J., Granger, S. J., Hawkins,J. M. B., Krueger, T., Naden P. S., Old, G., Quinton, J. N., Worsfold, P., and Haygarth, P. M. (2007) Grasslands, sediment, colloids and phosphorus: an interdisciplinary team approach with the �GrasP� project. Diffuse Phosphorus Loss Risk Assessment, Mitigation Options and Ecological Effects in River Basins Proceedings of the The 5th International Phosphorus Workshop (eds Heckrath, G. Rub�k, G. H. and Kronvang, B., 3-7 September 2007 in Silkeborg, Denmark
A.del Prado, L.M. C�rdenas, J. M. B Hawkins, L. Brown, S. Cuttle, E. Jewkes�and D Scholefield., (2007) Blueprints for sustainable nutrient use in dairy grassland-based production.�Proceedings of the 15th Nitrogen Workshop, Lleida, Spain, May 28-30th 2007.
Hawkins, J. M. B., Scholefield, D. and Braven, J., (2006). Dissolved free and combined amino acids in surface runoff and drainage waters from drained and undrained grassland under different fertilizer management. Environmental Science and Technology, 40, (16), 4887-4893.
Caneiro, J., Cardenas, L., Hatch, D. , Trindad, H., Hawkins, J., Scholefield, D., Chadwick, D. (2005) Cattle slurry amended with nitrification inhibitors: effects on nitrous oxide, dinitrogen and methane emissions. IGC Satellite Conference, Dublin, July 2005.
Hatch , D., Trindade, H. Cardenas, L., Carneiro, J. Hawkins, J. , Scholefield, D. and Chadwick, D. (2005) Laboratory study of the effects of two nitrification inhibitors on greenhouse gas emissions from a slurry-treated arable soil: impact of diurnal temperature cycle. Biology and Fertility of Soils, 41, 225-232.
Hawkins, J. M. B., (2004). Amino acids as diagnostics of soil and soil water quality. PhD Thesis. The School of Earth, Ocean and Environmental Science, Faculty of Science, University of Plymouth, Devon, UK, 310 pages.
Ganzeveld, L. , Li, C. , Cardenas, L. , Hawkins, J. , Kirkman, G. (2004) Nitrogen Emissions from Soils. In: Emissions of Atmospheric Trace Compounds. Advances in Global Change Research Volume 18. (Eds. Granier, C., Artaxo, P. Reeves, C. E.). Kluwer Academic Publishers, Dordrecht, Netherlands.
Hawkins, J. M. B. and Scholefield, D. S. (2004) Scoping the potential of farm ponds to provide environmental benefits. Defra Final Report. 60 pages.
Bol, R. , Toyoda, S. , Yamulki, S. , Hawkins, J. M. B. , Cardenas, L. M. , Yoshida, N. (2003) Dual isotope and isotopomer ratios of N2O emitted from a temperate grassland soil after fertiliser application. Rapid Communications in Mass Spectroscopy, 17, (22) 2550-2556.
Cardenas, L. M. , Hawkins. J. M. B. ,Chadwick, D. R. , Scholefield, D. Novel laboratory and field techniques to improve understanding of the denitrification process and enable the development of a new model. BBSRC Final Report.
Cardenas, L.M., Hawkins, J.M.B., Chadwick, D. Scholefield, D. (2003) Use of a 2-pool model to evaluate the effect of fertiliser application on nitrogen emissions from grassland soils, Proceedings of the 12th Nitrogen Workshop, Exeter, September 2003.
Cardenas, L. M. , Hawkins, J. M. B. , Chadwick, D. , Scholefield, D. (2003) Biogenic gas emissions from soils measured using a new automated laboratory incubation system. Soil Biology and Biochemistry, 35, (6), 867-870.
Cardenas, L. M. , Hawkins, J. M. B. , Martinez, J. , Chadwick, D. , Scholefield, D. (2002) Effect of carbon availability on N2 and N2O emissions. Workshop, CEMAGREF, Rennes, France, 10-12 June 2001.
Cardenas, L. M. , Hawkins, J. M. B. , Chadwick, D. , Scholefield, D. (2002) Study of denitrification in grassland soils in relation to carbon application. BIOGEMON 2002. 4th International Symposium on Ecosystem Behaviour, University of Reading, 17-21 August 2002.
Cardenas, L. M. , Hawkins, J. M. B. , Chadwick, D. R. , Scholefield, D. (2001) Application of an improved technique to evaluate controls on nitrous (N2O) emissions from grassland soils. Proceedings of an International Workshop on Emissions of Chemical Species and Aerosols into the Atmosphere, Paris, France, 19-22 June 2001.
Hawkins, J. M. B. , Scholefield, D. (2000) Leaching of dissolved organic N from grass - white clover pasture in SW England. Grassland Farming: Balancing Environmental and Economic Demands. Proceedings of the 18th General Meeting of the European Grassland Federation, Aalborg, Denmark, 22-25 May 2000 (Grassland Science in Europe, Vol 5) (Eds. Soegaard, K. , Ohlsson, C. , Hutchings, N. J. , Kristensen, T. , and Sehested, J.) 378-380.
Hawkins, J. M. B. , Scholefield, D. (1999) Dissolved free amino acids in surface lateral drainage from grazed grassland. Proceedings of the 10th Nitrogen Workshop, Copenhagen, Denmark, 1999.
Scholefield, D. , Chadwick, D. R. , Hawkins, J. M. B. (1999) Use of a novel incubation technique to measure N2O/N2 following surface or injected application of slurry. Grasslands 2000, Proceedings of the XVIII International Grassland Congress, Winnipeg, Manitoba, Saskatoon, Saskatchewan, Canada, 8-17 June, 1997 (Vol 2) (Eds. Buchanan-Smith, J. G. , Bailey, L. D. , and McCaughey, P), Can. Forage Council, Can. Soc. Agron., Can. Soc. Anim Sci.
Hawkins, J. M. B. , Scholefield, D., and Bol, R. (1998) The potential of amino acid distributions as diagnostics of soil quality. Ecological Aspects of Grassland Management, Proceedings of the 17th General Meeting of the European Grassland Federation, Debrecen Agricultural University, Debrecen, Hungary, 18-21 May, 1998 (Eds. Nagy, G. Peto, K.,). 555-558 BGS, Reading, UK.
Scholefield, D. , Hawkins, J. M. B. , Jackson, S. M. (1997) Use of a flowing helium atmosphere incubation technique to measure the effects of denitrification controls applied to intact cores of a clay soil. Soil Biology and Biochemistry, 29, (9-10), 1337-1344.
Scholefield, D. , Hawkins, J. M. B. , Jackson, S. M. (1997) Development of a helium atmosphere soil incubation technique for direct measurement of nitrous oxide and dinitrogen fluxes during denitrification. Soil Biology and Biochemistry, 29, (9-10), 1345-1352.
Hawkins, J. M. B. , Scholefield, D. (1997) The extent and pathways of transfer of organic N from fertilised and unfertilised grassland. Proceedings of the 5th British Grassland Society (BGS) Research Conference, Seale Hayne Faculty of Agriculture Food & Land Use, University of Plymouth, Newton Abbot, Devon, 8-10 September, 1997. BGS, Reading.
Scholefield, D. , Hawkins, J. M. B. (1997) Determination of controls over denitrification using a flowing helium atmosphere system. Gaseous Nitrogen Emissions from Grasslands (Eds. Jarvis, S. C. , Pain, B. F.), 27-36 (Chapter 3), CAB International, Wallingford.
Hawkins, J. M. B. , Scholefield, D. (1997) Leaching of organic N from grassland systems. Conference proceedings: Managing risks of nitrates to humans and the environment, Royal Society of Chemistry, University of Essex, September.
Hawkins, J. M. B. , Scholefield, D. (1996) Leaching of organic N from poorly draining grassland soil. Workshop: Measuring nutrient runoff from land to water, University of Leicester, December.
Hawkins, J. M. B. , Scholefield, D. (1996) Molybdate-reactive phosphorus losses in surface and drainage waters from permanent grassland. Journal of Environmental Quality, 25, (4), 727-732.
Hawkins, J. M. B. , Haygarth, P. M. , Jarvis, S. C. , Scholefield, D. (1996) Long-term study on the transfer of phosphorus from grassland soil to surface waters. Proceedings of Diffuse Pollution and Agriculture (Eds. Petchey, A. M. , D'Arcy, B. J. , Trust, C. A.,). 252-254 Scottish Agricultural College, Nevisprint Ltd.
Scholefield, D. , Hawkins, J. M. B. , Jackson, S. M. (1994) Use of a `flow-over' incubation technique without acetylene blocking to measure the effect of the factors controlling denitrification in a grassland soil Progress in Nitrogen Cycling, the 8th Nitrogen Cycling Workshop, University of Ghent, Belgium, 5-9 September 1994.
Hawkins, J. M. B. , Scholefield, D. (1994) Development of a `flow-over' technique to measure N2 and N2O fluxes during soil incubation. Progress in Nitrogen Cycling, the 8th Nitrogen Cycling Workshop, University of Ghent, Belgium, 5-9 September 1994.
Scholefield, D. , Hawkins, J. M. B. , Jackson, S. M. (1993) The effects of nitrate, water content and temperature on denitrification in a grassland soil measured using a "flow-over" technique without acetylene blocking. 4th AFRC Meeting on Plant and Soil Nitrogen Metabolism, 15-17 December 1993, Silsoe, UK.
Scholefield, D. , Tyson, K. C. , Garwood, E. A. , Armstrong, A. C. , Hawkins, J. M. B., Stone, A. C. (1993) Nitrate leaching from grazed grassland lysimeters: effects of fertilizer input, field drainage, age of sward and patterns of weather. Journal of Soil Science, 44, 601-613.
Hawkins, J. M. B. , Scholefield, D. (1993) Measurement of nitrogen and nitrous oxide fluxes using a novel technique. 4th AFRC Meeting on Plant and Soil Nitrogen Metabolism, 15-17 December 1993, Silsoe, UK.
Tyson, K. C. , Hawkins, J. M. B. , Stone, A. C. (1993) Final report on the AFRC-ADAS Drainage Experiment 1982-1992. North Wyke Research Station, IGER.
Tyson, K. C. , Hawkins, J. M. B. , Stone, A. C. (1992) The North Wyke grassland drainage experiment. Grass Farmer, 42, 21-23.
Scholefield, D. , Hawkins, J. M. B. , Blantern, P. J. (1991) Development of a soil core incubation technique for the measurement of denitrification. 3rd AFRC Meeting on Plant and Soil Nitrogen Metabolism, AFRC IGER, Aberystwyth.
Scholefield, D. , Corre, W. J. , Colbourn, P. , Jarvis, S. C. , Hawkins, J. M. B. , De Klein, C. A. M. (1990) Denitrification in grazed grassland soils assessed using the core incubation technique with acetylene inhibition. Proceedings of 13th General Meeting of the European Grassland Federation, Banska Bystrica, Czechoslovakia II 8-12.
Scholefield, D. , Hawkins, J. M. B. , Tyson, K. C. , Elliot, P. (1987) Better estimation of the losses of N through denitrification from pasture grazed beef cattle. Meeting on Plant and Soil Nitrogen Metabolism, Sussex, September 1987, Agricultural and Food Research Council, London.
PhD in Environmental Sciences (University of Plymouth)
BSc in Cognitive Psychology & Neurobiology (Open University)
HNC/D in Agriculture (Writtle Agricultural College)
Measures of esteem
- For University of Galway
- Steering Committee Member on Teagasc buffers project
- PhD Co-Supervisor: Tegan Darch
- Guest Editor for Journal of European Soil Science - special issue