Estimating Nitrogen Fixation by Pastures on a Regional or Continental Scale

With fertiliser N inputs dramatically increasing in Australia in recent years (Angus, 2001), regional and continental scale estimates of biological nitrogen fixation (BNF) are now required for assessing the risks of terrestrial and surface water eutrophication, groundwater contamination, and gaseous N emissions

Nitrogen fixation in Australian dairy systems: review and prospect

Quantitative measurement of N₂ fixation has rarely been conducted in Australian dairy pastures. The available data indicate that annual N₂ fixation rates in Australian dairy pastures are generally low, due to low pasture legume content. With typical legume contents of grazed pastures less than 30% of total pasture biomass production, annual N₂ fixation in herbage is usually much less than 50 kg ha⁻¹ year⁻¹. Other factors which are likely to be able to contribute to increased N₂ fixation input (rhizobia, mineral N management, soil acidity, soil water contents) will have little impact until such time as legume contents are increased. In contrast, for some hay systems, such as those using lucerne, N₂ fixation input is shown to be high (200–300 kg ha⁻¹ year⁻¹). While pasture clover contents remain low there is little value in study or measurement of N₂ fixation, nor in complex modelling, as N₂ fixation will be of little quantitative importance. However, where legume contents, and thus potential N₂ fixation are increased, there is scope for investigation into potential increases in N input from this source, which is invariably linked to fertiliser application, the management of grazing and the N returns in urine and dung. These are the major influences on sward N dynamics and legume N₂ fixation. The inoculant rhizobia used for white clover in Australia (TA1) is likely to be suboptimal. Isolated in Tasmania in 1953 it has been shown to be inferior in N₂ fixation compared with other strains on several occasions. Root pests and diseases are likely to be prevalent and impact directly on clover root growth and perhaps nodulation. Modelling is often used to describe the probable influence of management and/or climate on the operation of agricultural systems. Reliable modelling of N₂ fixation requires capacity to integrate the effects of grazing and pasture composition on soil mineral N dynamics, the influence of this mineral N on nodulation and on suppression of N₂ fixation, and environmental and management influences on soil rhizobial populations. Currently no models have demonstrated this capacity. At present, a suitably calibrated regression model is probably a good option for modelling N₂ fixation in Australian dairy pastures. Environmental benefits ensuing from increasing N₂ fixation and substituting this for fertiliser N are likely to be greater off-farm (reduced GHG emissions at site of fertiliser manufacture) than on, if current fertiliser management is optimal. Nevertheless substituting fixed N for fertiliser N would have modest environmental and feed efficiency benefits.Murray Unkovic

A recommended method for detecting salmonellae in composted biosolids

It has been found in Australia and in the United States that composting does not always result in the complete removal of salmonellae from biosolids. It is therefore likely that monitoring of composted Biosolids for salmonellae will be required in Australia to ensure the safety of biosolids products. At present rapid methods of detection such as PCR and ELISA are not sufficiently developed to monitor environmental samples. The relative efficiency of various culture methods for detecting salmonellae in composted biosolids was therefore investigated. On the basis of the results a presence/absence method is recommended for the detection of salmonellae in biosolids products. The recommended technique involves pre-enrichment of samples, followed by enrichment in Rappaport-Vassiliadis and mannitol selenite enrichment broths, and isolation on lysine mannitol glycerol agar

Biological nitrogen fixation by legume cover plants in oil palm plantations: calibration of the ureide technique and effects of plantation age and soil nitrate

Background and Aims. To sustainably manage N in oil palm systems quantities of N fixed by cover legumes need to be understood. Current values are scarce, based on shoot N measures and do not include litter which releases nitrate as it decomposes. We aimed to quantify N2 fixed by legumes under oil palm systems in PNG and to determine if soil nitrate influenced dependence on N2 fixation (Ndfa). Methods. The ureide technique for estimating tropical legume Ndfa was calibrated for Calapogonium mucunoides and Pueraria phaseoloides using 15N isotope dilution, and then used to assess Ndfa for legume cover under oil palms (2 to 25 years old) in Papua New Guinea. Amounts of fixed N in aboveground legume biomass (shoot plus litter) were calculated incorporating % groundcover. Soil nitrate under the legume litter was also measured. Results. Legume Ndfa was highly negatively correlated with soil nitrate concentration but independent of palm age. Legume groundcover, shoot and litter dry matter, and quantity of fixed N were greater under oil palms less than 5 years old, decreasing under older plantations where solely C. caeruleum was present. DM and N content of litter were similar to shoots for legumes in plantations less than 6 years old. Conclusion. The calibrated ureide technique can be used, together with estimates of annual legume N accumulation, to quantify N input from legume groundcover during the life cycle of oil palm plantations and other tropical ecosystems, in order to support more sustainable management of N

Foundations of Dance Movement Psychotherapy Practice in Profound and Multiple Learning Disabilities: 'when disabilities disappear'

Introduction This article discusses the mode of practice co-constructed by two Dance Movement Psychotherapists for co-facilitating long-term Dance Movement Psychotherapy (DMP) sessions with a closed group of adults in a Learning Disability day centre for a London Primary Care Trust. We present our Foundations of Practice with clients diagnosed with Profound and Multiple Learning Disabilities (PMLD) and an ethos for group-work (Shotter 1994: p39) established over time. We view this as the beginning of our journey in writing about our professional relationship with this client group, and we hope that it will stimulate others to contribute to the writing and development of practice-based-evidence for working with adults with Profound and Multiple Learning Disabilities. Coming from a place of curiosity regarding our practice with non-verbal clients, we have reflected on our own perceived learning and physical disabilities. This reflection has been a means for us to recognise the roots of our practice as co-working DMPs with adults with PMLD. In this paper, we bring to light and put some words on what may be one of the most non-verbal psychotherapeutic relationships. We acknowledge how our clients may be perceived in society, and the implication of having a PMLD diagnosis. We name the dichotomy between the subjectivity and authority inherent to our role as DMPs, and our intention to be curious and open to our clients' unique way of expressing themselves. Recognising these positions and locating our practice within a social constructionist framework we identify tools and techniques which inform our work. Movement improvisation offers us a means to ground our practice within current dance and psychotherapeutic theory. Considering breath as a vital and natural life giving experience inherent to all beings, we reflect on our roles as DMPs with this client group, particularly on the therapist's choices in his/her relationship with adults with PMLD. The clients considered in this paper are adults diagnosed with Profound and Multiple Learning Disabilities, individuals who hold multiple complex diagnoses; involving neurological, physiological and physical impairment together with mental health diagnosis.sch_occBest, P (2003). 'Interactional Shaping within Therapeutic Encounters: Three dimensional dialogues' in The USA Body Psychotherapy Journal, 2.1, pp.26-44 Bethesda MD U.S.A: USABP Bonefant, Y (2006). 'The embodied politics of intention, therapeutic intervention and artistic practice' in Payne, H (editorin- chief) Body, Movement and Dance in Psychotherapy. Sept 2006 1(2): pp115-127 Oxon UK: Routledge/Taylor & Francis Group Burr, V (2004). Social Constructionism London: Routledge Butt, C (2007). An Investigation into the Use of Interpersonal Touch in Dance Movement Therapy with Adults with Profound and Multiple Learning Disabilities Unpublished MA Dissertation, Roehampton University London Carnaby, S. & Cambridge, (2002). 'Getting Personal: An Exploratory Study of Intimate Care Provision for People with Profound and Multiple Intellectual Disabilities', Journal of Intellectual Disability Research No.46 (2), 120-132. Cecchin, G (1992). 'Constructing Therapeutic Possibilities' in McNamee, S. and K, Gergen, eds. (1996) Therapy as Social Construction London: Sage Publications Dobson, S., Carey, L., Conyers, I., Upadhyaya, S. and Raghavan, R (2004). 'Learning about Touch: An Exploratory Study to Identify the Learning Needs of Staff Supporting People with Complex Needs', Journal of Learning Disabilities, No.8 (2), 113-129 Halprin, D (2003). The Expressive Body in Life, Art and Therapy. Working with Movement, Metaphor and Meaning London: Jessica Kingsley Publishers Keleman, S (1975). Your Body Speaks Its Mind California: Center Press Keleman, S (1981). The Human Ground - Sexuality, Self and Survival California: Center Press Kvale, S (1996). InterViews, An Introduction to Qualitative Research Interviewing. London: Sage Publications 1 Writing 'response-ability', our intention is to invite the reader to consider the etymological root of the word 'responsibility' and be reminded that the origins of the word 'responsibility' lie in 'our ability to respond'. Meekums, B (2005). Dance Movement Therapy: A Creative Psychotherapy Approach London: Sage Publications Parker, G. & Best, P. A (2005). 'Reflecting Processes & Shifting Positions in Dance Movement Therapy', e-motion Quarterly Spring 2004 Vol XIV, no 10 U.K: ADMP UK Shaw, R (2003). The Embodied Psychotherapist: The Therapist's Body Story Hove: Brunner-Routledge, Taylor & Francis Group Sheehy, K. and Nind, M (2005). 'Emotional well-being for all: mental health and people with profound and multiple learning disabilities', British Journal of Learning Disabilities, No.33, 34-38 Sherborne, V (2001). Developmental Movement for Children London: Worth Publishing Shotter, J (1994). Conversational Realities - Constructing Life through Language London: Sage Publications Soth, M (2006). 'What Therapeutic Hope for a Subjective Mind in an Objectified Body?' in Corrigall, Payne & Wilkinson eds (2006) About A Body - Working With the Embodied Mind in Psychotherapy. London: Routledge Unkovich, G (2009). 'Thank You -I will have my body back now!' e - motion Quarterly Winter 2008 Vol. XVIII No 4 U.K: ADMP U.K Yalom, I (1985). The Theory and Practice of Group Psychotherapy (3rd Edition) U.S.A: Basic Books Weblinks: About Profound and Multiple Learning Difficulties, PMLDNetwork Definition Factsheet 2009. Internet WWW page at URL http://www.pmldnetwork.org /what_do_we_want/who_are_we_campaigning_for.htm (accessed 03.05.09) British Institute of Learning Disabilities. Internet WWW page at URL http://bild.org.uk (accessed 10.05.09) Valuing People Now, a new three year strategy for people with learning disabilities (2009) full pdf version, internet WWW page at URL http://www.dh.gov.uk/en/SocialCare/Deliveringadultsocialcare/Learningdisabilities/DH_079430 (accessed 03.05.09) World Health Organisation. Internet WWW page at URL http://who.int/en (accessed 03.05.09)XIX -pub2336pub

Field measurements of bare soil evaporation and crop transpiration, and transpiration efficiency, for rainfed grain crops in Australia - A review

Available online 30 April 2018Australian agriculture is dominated by rainfed cropping in environments where evaporative demand greatly exceeds annual rainfall. In this paper we review field measurements of crop transpiration and bare soil evaporation under rainfed grain crops, and crop transpiration efficiencies. Crop transpiration is typically calculated from the difference between evapotranspiration and bare soil evaporation, however, while the former is readily measured, the latter is difficult to obtain. For wheat we found only 19 studies which measured the critical water balance parameters of bare soil evaporation and crop transpiration in Australia, and very many fewer for other crops. From the studies reported for wheat, on average 38% of evapotranspiration was lost to direct soil evaporation. Data for other crops are insufficient to ascertain whether they are similar or different to wheat in terms of the relative contributions of Es and T to the water balance. Although it may have occurred in practice, we can find no field measurements of the crop water balance to demonstrate an increase in crop transpiration at the expense of bare soil evaporation as a function of improvements in agronomic practices in recent decades. Although it is thought that crop transpiration efficiencies are primarily a function of vapour pressure deficit, transpiration efficiencies reported in the literature vary considerably within crops, even after accounting for vapour pressure deficit. We conclude that more reliable estimates of crop transpiration efficiency would be highly valuable for calculating seasonal transpiration of field grown crops from shoot biomass measurement, and provide an fruitful avenue for exploring water use efficiency of grain crops.Murray Unkovich, Jeff Baldock, Ryan Farquharso