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The aromatic carbon structure is a defining property of chars and is often expressed with the help of two concepts: (i) aromaticity and (ii) degree of aromatic condensation. The varying extent of these two features is assumed to largely determine the relatively high persistence of charred material in the environment and is thus of interest for, e.g., biochar characterization or carbon cycle studies. Consequently, a variety of methods has been used to assess the aromatic structure of chars, which has led to interesting insights but has complicated the comparison of data acquired with different methods. We therefore used a suite of seven methods (elemental analysis, MIR spectroscopy, NEXAFS spectroscopy, 13C NMR spectroscopy, BPCA analysis, lipid analysis and helium pycnometry) and compared 13 measurements from them using a diverse sample set of 38 laboratory chars. Our results demonstrate that most of the measurements could be categorized either into those which assess aromaticity or those which assess the degree of aromatic condensation. A variety of measurements, including relatively inexpensive and simple ones, reproducibly captured the two aromatic features in question, and data from different methods could therefore be compared. Moreover, general patterns between the two aromatic features and the pyrolysis conditions were revealed, supporting reconstruction of the highest heat treatment temperature (HTT) of char.

Few systematic efforts have been reported to develop higher degree by research student skills for writing publishable articles in science and technology fields. There is a need to address this lack in the light of the current importance of publication to science research students and the high supervisor workload entailed in repeated draft correction, especially when students use English as an additional language. An interdisciplinary teaching approach to address this need has recently been developed featuring analysis frameworks from applied linguistics (AL) research, with successful outcomes in short, stand-alone workshops facilitated by an applied linguist teaching alone or in teams with scientists. Its use by a scientist alone has not previously been investigated, although scientists are well placed to address this development need. We investigate the suitability and effectiveness of this approach for use by a scientist to embed training, in the context of the first two years of operation of a school-level writing group programme, and identify features of the approach that align with participants' perceptions of benefit. Student response to the programme has been strongly positive, with increased confidence to write for publication and complete their degrees, and high activity towards publishing papers on their degree research. The presenter reports maintenance of his own publication output in spite of the time spent on this training, as a result of increased writing efficiency. Features of the approach that map to perceived benefit include its basis in AL frameworks for analysis of student-provided example papers; incorporation of relevant aspects of English usage and grammar in the frameworks; and inclusion of response to reviewer comments as an integral part of article writing.

Few studies have considered the influence of climate on organic phosphorus (P) speciation in soils. We used sodium hydroxide-ethylenediaminetetra-acetic acid (NaOH-EDTA) soil extractions and solution [sup.31]P nuclear magnetic resonance spectroscopy to investigate the soil P composition of five alpine and sub-alpine soils. The aim was to compare the P speciation of this set of soils with those of soils typically reported in the literature from other cold and wet locations, as well as those of other Australian soils from warmer and drier environments. For all alpine and sub-alpine soils, the majority of P detected was in an organic form (54-66% of total NaOH-EDTA extractable P). Phosphomonoesters comprised the largest pool of extractable organic P (83-100%) with prominent peaks assigned to myo- and scyllo-inositol hexakisphosphate ([IP.sub.6]), although trace amounts of the neo- and n-chiro-[IP.sub.6] stereoisomers were also present. Phosphonates were identified in the soils from the coldest and wettest locations; [alpha]- and [beta]-glycerophosphate and mononucleotides were minor components of organic P in all soils. The composition of organic P in these soils contrasts with that reported previously for Australian soils from warm, dry environments where inositol phosphate ([IP.sub.6]) peaks were less dominant or absent and humic-P and [alpha]- and [beta]-glycerophosphate were proportionally larger components of organic P. Instead, the soil organic P composition exhibited similarities to soils from other cold, wet environments. This provides preliminary evidence that climate is a key driver in the variation of organic P speciation in soils. Additional keywords: climate, organic matter, solution [sup.31]P NMR spectroscopy., Introduction The soil organic matter (SOM) content of soils is influenced by all the key soil-forming factors, i.e. parent material, topography, climate, vegetation and time. In broad terms, the influence [...]

Organic phosphorus (P) plays an important role in the soil P cycle. It is present in various chemical forms, the relative amounts of which vary among soils, due to factors including climate, land use, and soil type. Few studies have investigated co-variation between P types or stoichiometric correlation with the key elemental components of organic matter-carbon (C) and nitrogen (N), both of which may influence P pool structure and dynamics in agricultural soils. In this study we determined the organic P speciation of twenty Australian Red Chromosols soils, a soil type widely used for cropping in Australia. Eight different chemical forms of P were quantified by 31P NMR spectroscopy, with a large majority (>90%) in all soils identified as orthophosphate and humic P. The strongest correlations ([r.sup.2] = 0.77-0.85, P Additional keywords: carbon, diester phosphate, monoester phosphate, nitrogen, organic P, solution [sup.31]P NMR spectroscopy, stoichiometry., Introduction Organic phosphorus (P) comprises a substantial proportion of total P in most soils (Williams and Steinbergs 1958; Harrison 1987). Although it is not directly plant available, it plays a [...]

Pasture-based animal production systems, which occupy a significant proportion of the landscape in Victoria, Australia, have historically been nutrient-limited, with phosphorus (P) often the most limiting nutrient. The Permanent Top-Dressed (PTD) pasture experiment was established in 1914 at the Rutherglen Research Station, Victoria, to investigate the management of this deficiency. The main objective of the PTD experiment was to demonstrate the value of adding P fertiliser at two rates to increase pasture productivity for lamb and wool production. We report on the status of the PTD soils after 100 years, investigating the long-term implications of continuous grazing and fertiliser management (0, 125 and 250 kg/ha of superphosphate every second year) of non-disturbed pasture. We investigated the long-term effects of P fertiliser on the forms and distribution of P and other relevant soil parameters. In the fertilised treatments, P has accumulated in the surface soils (0-10 cm) as both orthophosphate and organic P, with an Olsen P of 16-21 mg P/kg, which is non-limiting for pasture production. In the treatment with 250 kg superphosphate, there has also been movement of P down through the soil profile, probably due to the high sand content of the surface soil and the transfer through the profile of small quantities of water-soluble P and P bound to organic ligands. Over time, the site has continued to acidify (surface 0-10 cm); the soil acidity combined with aluminium (Al) concentrations in the fertilised treatments approach a level that should impact on production and where broadcast lime would be recommended. After 100 years of non-disturbed pasture, the surface soils of these systems would be in a state of quasi-equilibrium, in which the fertilised systems have high levels of carbon (C), nitrogen, P and exchangeable Al. The continued stability of this system is likely dependent upon maintaining the high C status, which is important to nutrient cycling and the prevention of Al phytotoxicity. There are two risks to this system: (i) the declining pH; and (ii) soil disturbance, which may disrupt the equilibrium of these soils and the bio- chemical processes that maintain it. Additional keywords: acidification, fertiliser, long-term field experiment, MIR, organic phosphorus, PTD, 3IP NMR. Received 30 August 2014, accepted 13 January 2015, published online 30 June 2015, Introduction Pasture-based animal production systems occupy a significant proportion of the landscape in Victoria, Australia. Productivity in these systems has historically been nutrient-limited. Phosphorus (P) is often the most limiting [...]