Archive for the category: Feature Presentation

Clemens Scheer¹, Mary Firrell², Peter Deuter², David Rowlings¹, Ian Porter³, Peter Grace¹

¹Institute for Future Environments, Queensland University of Technology, Brisbane, QLD 4000, Australia, clemens.scheer@qut.edu.au

²Department of Agriculture, Fisheries and Forestry (Queensland), Gatton Research Station, QLD 4343, Australia  

³School of Life Sciences, LaTrobe University, Bundoora, Vic 3083,Australia

Abstract

Vegetable production systems are characterised by intensive production with high inputs of nitrogen fertiliser and irrigation water. Consequently, high emissions of nitrous oxide have been reported. The use of nitrification inhibitors (NI) offers an effective method to reduce N₂O emissions, whilst maintaining yield and increasing nitrogen use efficiency. However, only limited data are currently available on the use of NI in vegetable cropping systems. A field experiment was conducted to investigate the effect of the nitrification inhibitor 3,4-Dimethylpyrazol phosphate (DMPP) in combination with reduced N fertilizer application rates on N₂O emissions and yield from a typical vegetable rotation in sub-tropical Australia. Annual N₂O emissions ranged from 0.59 to 1.37 kgN/ha for the different fertiliser treatments. A 40% reduced fertilizer rate combined with DMPP reduced N₂O emissions by more than half but achieved a comparable yield to the standard grower’s practice in two out of three crops. We conclude that DMPP shows a great potential for reducing N₂O emissions from vegetable systems. However, further research is required to understand under what conditions reduced N rates of DMPP coated fertiliser are applicable and to determine the long-term effect of such a fertiliser regime over extended cropping cycles.

Sanz-Cobeña¹, A., Lassaletta, L.², Aguilera, E.³, del Prado, A.⁴, Garnier, J.^5,6, Billen, G. ^5,6, Iglesias, A.¹, Sánchez, B.¹, Guardia, G.¹, Abalos, D.⁷, Plaza-Bonilla, D.⁸, Puigdueta, I¹, Moral, R.⁹, Galán, E.⁴, Arriaga, H.¹⁰, Merino, P.¹⁰, Infante-Amate, J.³, Meijide, A.¹¹, Pardo, G.⁴, Alvaro-Fuentes, J.¹², Gilsanz, C.¹³, Báez, D.¹³, Doltra, J.¹⁴, González-Ubierna, S.¹⁵, Cayuela, M.L.¹⁶, Menendez, S.¹⁷, Diaz-Pines, E.¹⁸, Le-Noe, J.⁴, Quemada, M.¹, Estellés, F.¹⁹, Calvet, S.¹⁹, van Grinsven, H.², Westhoek, H.², Sanz, M.J.⁶, Sánchez-Jimeno, B.²⁰, Vallejo, A.¹, Smith, P.²¹

¹ ETSI Agronomos, Technical University of Madrid, Ciudad Universitaria, 28040 Madrid, Spain a.sanz@ump.es
² PBL Netherlands Environmental Assessment Agency, Bilthoven, PO Box 303, 3720 AH Bilthoven, the Netherlands
³ Universidad Pablo de Olavide, Ctra. de Utrera, km. 1, 41013, Sevilla, Spain
⁴ Basque Centre for Climate Change (BC3), Alameda Urquijo 4-4, 48008, Bilbao, Spain CNRS, UMR
⁵ CNRS,^, UMRMetis 7619, BP105, 4 place Jussieu, 75005, Paris, France
⁶ UPMC, UMR Metis 7619, BP105, 4 place Jussieu, 75005, Paris, France
⁷ Department of Soil Quality, Wageningen University, PO Box 47, Droevendaalsesteeg 4, Wageningen 6700AA, The Netherlands
⁸ INRA, UMR-AGIR, 24 Chemin de Borde Rouge –Auzeville, CS 52627, 31326 Castanet-Tolosan cedex, France
⁹ Department of Agrochemistry and Environment, EPSO, Miguel Hernandez University, 03312 Orihuela, Alicante, Spain
¹⁰ NEIKER-Tecnalia, Conservation of Natural Resources, Bizkaia Technology Park, P. 812, 48160, Derio, Bizkaia, Spain
¹¹ Bioclimatology, Georg-August-Universität Göttingen, Büsgenweg 2, 37077, Göttingen, Germany
¹² Soil and Water Dpt, Estacion Experimental de Aula Dei (EEAD), Spanish National Research Council (CSIC,), Av. Montañana, 1005, 50059 Zaragoza, Spain
¹³ Mabegondo Agricultural Research Centre (CIAM-INGACAL), Xunta de Galicia, Carretera AC-542 de Betanzos a Mesón do Vento, km 7, 15318 Abegondo, A Coruña, Spain
¹⁴ Cantabrian Agricultural Research and Training Centre, CIFA, c/Héroes 2 de Mayo 27, 39600 Muriedas, Spain
¹⁵ Faculty of Pharmacy. Complutense University of Madrid. Ciudad Universitaria. Pza. Ramón y Cajal s/n, 28040 Madrid, Spain
¹⁶ Departamento de Conservación de Suelos y Aguas y Manejo de Residuos Orgánicos. CEBAS-CSIC. Campus Universitario de Espinardo. 30100 Murcia. Spain.
¹⁷ University of the Basque Country UPV/EHU, Department of Plant Biology and Ecology, Apdo. 644, 48080, Bilbao, Spain
¹⁸ Institute of Meteorology and Climate Research, Atmospheric Environmental Research. Karlsruhe Institute of Technology. Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen, Germany.
¹⁹ ICTA, Universitat Politècnica de València, Camino de Vera s/n 46022, Valencia
²⁰ Dirección General de Investigación Científica y Técnica. Ministerio de Economía y Competitividad. Gobierno de España. Pº. de la Castellana, 162, 28046 Madrid, España.
²¹ Institute of Biological and Environmental Sciences, University of Aberdeen, 23 St Machar Drive,Aberdeen, AB24 3UU, UK

Abstract

In this review we aimed to synthetize and analyze the most promising GHGs mitigation strategies for Mediterranean cropping systems. A description of most relevant measures, based on the best crop choice and management by farmers (i.e., agronomical practices), was firstly carried out. Many of these measures can be also efficient in other climatic regions, but here we provide particular results and discussion of their efficiencies for Mediterranean cropping systems. An integrated assessment of management practices on mitigating each component of the global warming potential (N₂O and CH₄ emissions and C sequestration) of production systems considering potential side-effects of their implementation allowed us to propose the best strategies to abate GHG emissions, while sustaining crop yields and mitigating other sources of environmental pollution (e.g. nitrate leaching and ammonia volatilization).

Maria L. Cayuela^1*, Eduardo Aguilera², Alberto Sanz-Cobena³, Dean C. Adams^4,5, Diego Abalos⁶, Louise Barton⁷, Rebecca Ryals⁸, Whendee L. Silver⁹, Marta A. Alfaro¹⁰, Valentini A. Pappa^11,12, Pete Smith¹³, Josette Garnier¹⁴, Gilles Billen¹⁴, Lex Bouwman^15,16, Alberte Bondeau¹⁷, Luis Lassaletta¹⁵

¹Departamento de Conservación de Suelos y Aguas y Manejo de Residuos Orgánicos. CEBAS-CSIC. Campus Universitario de Espinardo. 30100 Murcia. Spain. mlcayuela@cebas.csic.es

² Universidad Pablo de Olavide, Ctra. de Utrera, km. 1, 41013, Sevilla, Spain

³ ETSI Agronomos, Technical University of Madrid, Ciudad Universitaria, 28040 Madrid, Spain

⁴ Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames IA, USA, 50010

⁵ Department of Statistics, Iowa State University, Ames IA, USA, 50010                                                                   

⁶ Department of Soil Quality, Wageningen University, PO Box 47, Droevendaalsesteeg 4, Wageningen 6700AA, The Netherlands

⁷ Soil Biology and Molecular Ecology Group, School of Geography and Environmental Sciences, UWA Institute of Agriculture, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia

⁸ Department of Natural Resources and Environmental Sciences, University of Hawaii, Manoa, Honolulu HI, 96822, USA

⁹ Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94707, USA

¹⁰Instituto de Investigaciones Agropecuarias, Centro Regional de Investigación Remehue, Casilla 24-O, Osorno, Chile

¹¹ Agricultural University of Athens, Department of Crop Science, Iera Odos 75, 11855 Athens, Greece

¹² Texas A&M University, 302H Williams Administration Bldg, College Station, TX 77843-3372, USA

¹³ Institute of Biological and Environmental Sciences, University of Aberdeen, 23 St Machar Drive, Aberdeen, AB24 3UU, UK

¹⁴ CNRS/UPMC, UMR Metis, 4 Place Jussieu, 75005 Paris, France

¹⁵ PBL Netherlands Environmental Assessment Agency, Bilthoven, PO Box 303, 3720 AH Bilthoven, The Netherlands

¹⁶ Department of Earth Sciences – Faculty of Geosciences, Utrecht University, PO Box 80021, 3508 TA Utrecht, The Netherlands

¹⁷ Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE) Aix Marseille Université, CNRS, IRD, Avignon Université. Aix-en-Provence, France.

Abstract

Studies on soil N₂O emissions from Mediterranean climate regions are less abundant than in other temperate areas and they are often not included in recent reviews and meta-analyses. In this paper we aimed at collecting and synthesizing all available current data from field studies on N₂O emissions across Mediterranean climate regions. We calculated through meta-analytical methods the averaged emission factor (EF, the percentage of fertilizer N applied that is transformed and emitted as N₂O) for Mediterranean cropping systems, which was found to be significantly lower (0.5%) than the IPCC default value (1%). We found that soil properties had no significant effect on N₂O emissions, but the irrigation system and the type and rate of applied N fertilizer influenced EFs. Rain-fed crops in Mediterranean regions had, in average, lower emissions (EF: 0.27%) than irrigated crops (EF: 0.63%). Drip irrigation systems showed 44% lower emission factors than sprinkler irrigation methods. Regarding the different N fertilizers, liquid slurries showed the highest EF, slightly lower, but not significantly different to 1%, whereas the remainder of the fertilizer types were significantly lower than 1%. Increasing the rate of nitrogen fertilizer led to higher EFs. The use of nitrification and ammonification inhibitors significantly reduced emissions (EF: 0.14%) and therefore seems a good strategy to mitigate direct N₂O emissions under Mediterranean conditions.

Rui Liu¹, Helen Suter¹, Helen L Hayden², Jizheng He¹, Deli Chen¹

¹ Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Victoria 3010, Australia

² Department of Economic Development, Jobs, Transport and Resources, Bundoora, Victoria 3083, Australia

Abstract

The continuous increase of the greenhouse gas nitrous oxide (N₂O) in the atmosphere due to increasing anthropogenic nitrogen input in agriculture has become a global concern. In recent years, identification of the microbial sources responsible for soil N₂O production has substantially advanced with the development of isotope enrichment techniques and the discovery of specific nitrogen-cycling functional genes. However, little information is available to effectively quantify the N₂O produced from different microbial pathways (i.e. nitrification and denitrification). ¹⁵N-tracing incubation experiments were conducted, using soil from different land-uses, under controlled laboratory conditions to quantify nitrification-sourced N₂O production. Nitrification was found to be the main contributor to N₂O production, contributing to 96.7% of the N₂O emissions in the sugarcane soil followed by 70.9% in the cereal cropping soil and 70.9% in the dairy pasture soil, while only around 20.0% of N₂O was produced from nitrification in vegetable soil. The greatest contribution from nitrification was observed at 50% and 70% WFPS regardless of soil temperature. At 50%, 70% and 85% WFPS, nitrification contributed 87%, 80% and 53% of total N₂O production, respectively at 25°C, and 86%, 74% and 33% of total N₂O production, respectively at 35°C. These findings can be used to develop better models for simulating N₂O from nitrification to inform soil management practices for improved N use efficiency.

Lynne Macdonald¹, Mark Farrell¹ and Jeff Baldock¹

¹ CSIRO Agriculture, PMB2, Glen Osmond, SA 5064, Australia (lynne.macdonald@csiro.au)

Abstract

The carbon (C) and nitrogen (N) cycles in soil are intrinsically linked.  Recently, and with particular reference to increased awareness of climatic change, there has been focus on increasing sequestration of C in agricultural soils as a potential greenhouse gas mitigation strategy.  However, increased C content in soils often also leads to an increased rate of both C and N cycling.  In the context of C accounting and defining the net greenhouse gas benefits of sequestering atmospheric CO₂-C in soil, it is important to understand the potential implications of building soil C on the flux of N₂O generated by N cycling processes (Zaehle et al. 2011).