Soil and litter phosphorus-31 nuclear magnetic resonance spectroscopy: extractants, metals, and phosphorus relaxation times

Phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy is an excellent tool with which to study soil organic P, allowing quantitative, comparative analysis of P forms. However, for 31P NMR to be tative, all peaks must be completely visible, and in their correct relative proportions. There must be no line broadening, and adequate delay times must be used to avoid saturation of peaks. The objective of this study was to examine the effects of extractants on delay times and peak saturation. Two samples (a forest litter and a mineral soil sample) and three extractants (0.25 M NaOH, NaOH plus Chelex (Bio-Rad Laboratories, Hercules, CA), and NaOH plus EDTA) were used to determine the differences in the concentration of P and cations solubilized by each extractant, and to measure spin-lattice (T1) relaxation times of P peaks in each extract. For both soil and litter, NaOH-Chelex extracted the lowest concentrations of P. For the litter sample, T1 values were short for all extractants due to the high Fe concentration remaining after extraction. For the soil sample, there were noticeable differences among the extractants. The NaOH-Chelex sample had less Fe and Mn remaining in solution after extraction than the other extractants, and the longest delay times used in the study, 6.4 s, were not long enough for quantitative analysis. Delay times of 1.5 to 2 s for the NaOH and NaOH-EDTA were adequate. Line broadening was highest in the NaOH extracts, which had the highest concentration of Fe. On the basis of these results, recommendations for future analyses of soil and litter samples by solution 31P NMR spectroscopy include: careful selection of an extractant; measurement of paramagnetic ions extracted with P; use of appropriate delay times and the minimum number of scans; and measurement of T1 values whenever possible.     

Optimizing phosphorus characterization in animal manures by solution phosphorus-31 nuclear magnetic resonance spectroscopy

A procedure involving alkaline extraction and solution 31P nuclear magnetic resonance (NMR) spectroscopy was developed and optimized for the characterization of P in animal manures (broiler, swine, beef cattle). Inclusion of ethylenediaminetetraacetic acid (EDTA) in the alkaline extraction solution recovered between 82 and 97% of the total P from the three manures, which represented a significant improvement on recovery in NaOH alone. Low concentrations of paramagnetic ions in all manure extracts meant that relatively long delay times (> 5 s) were required for quantitative analysis by solution 31P NMR spectroscopy. The manures contained inorganic orthophosphate, orthophosphate monoesters, orthophosphate diesters, and inorganic polyphosphates, but results were markedly influenced by the concentration of NaOH in the extractant, which affected both spectral resolution and the apparent P composition of the extracts. For example, extraction of swine manure and broiler litter with 0.5 M NaOH + 50 mM EDTA produced remarkable spectral resolution that allowed accurate quantification of the four signals from phytic acid, the major organic P compound in these manures. In contrast, more dilute NaOH concentrations produced considerable line broadening that obscured individual signals in the orthophosphate monoester region of the spectra. Spectral resolution of cattle manure extracts was relatively unaffected by NaOH concentration. Improvements in spectral resolution of more concentrated NaOH extracts were, however, compromised by the disappearance of phospholipids and inorganic polyphosphates, notably in swine and cattle manure extracts, which indicated either degradation or a change in solubility. The optimum extraction conditions will therefore vary depending on the manure type and the objectives of the study. Phytic acid can be accurately quantified in swine manure and broiler litter by extraction with 0.5 M NaOH + 50 mM EDTA, while a more dilute NaOH concentration should be used for complete P characterization or comparison among different manure types.     

Wet chemical and phosphorus-31 nuclear magnetic resonance analysis of phosphorus speciation in a sandy soil receiving long-term fertilizer or animal manure applications

In areas under intensive livestock farming and with high application rates of animal manure, inorganic and organic phosphorus (P) may be leached from soils. Since the contribution of these P compounds to P leaching may differ, it is important to determine the speciation of P in these soils. We determined the effect of various fertilization regimes on the P speciation in NaOH-Na2EDTA (ethylenediaminetetraacetic acid) and water extracts of acidic sandy soil samples from the top 5 cm of grassland with wet chemical analysis and 31P nuclear magnetic resonance (NMR) spectroscopy. These soils had been treated for a period of 11 years with no fertilizer (control), N (no P application), N-P-K, or different animal manures. Inorganic P was highly elevated in the NaOH-Na2EDTA extracts of the soils amended with N-P-K or animal manures, while organic P increased only in the soil treated with pig slurry. Water-extractable P showed a similar trend. As indicated by 31P NMR, orthophosphate monoesters were the main organic P compounds in all soils. Our results suggest that long-term applications of large amounts of P fertilizer and animal manures caused an accumulation of inorganic P, resulting in an increase of the potential risk related to mobilization of inorganic P in the top 5 cm of these soils.     

Comparison of phosphorus forms in wet and dried animal manures by solution phosphorus-31 nuclear magnetic resonance spectroscopy and enzymatic hydrolysis

Both enzymatic hydrolysis and solution (31)P nuclear magnetic resonance (NMR) spectroscopy have been used to characterize P compounds in animal manures. In this study, we comparatively investigated P forms in 0.25 M NaOH/0.05 M EDTA extracts of dairy and poultry manures by the two methods. For the dairy manure, enzymatic hydrolysis revealed that the majority of extracted P was inorganic P (56%), with 10% phytate-like P, 9% simple monoester P, 6% polynucleotide-like P, and 18% non-hydrolyzable P. Similar results were obtained by NMR spectroscopy, which showed that inorganic P was the major P fraction (64-73%), followed by 6% phytic acid, 14 to 22% other monoesters, and 7% phosphodiesters. In the poultry manure, enzymatic hydrolysis showed that inorganic P was the largest fraction (71%), followed by 15% phytate-like P and 1% other monoesters, and 3% polynucleotide-like P. NMR spectroscopy revealed that orthophosphate was 51 to 63% of extracted P, phytic acid 24 to 33%, other phosphomonoesters 6 to 12%, and phospholipids and DNA 2% each. Drying process increased orthophosphate (8.4% of total P) in dairy manure, but decreased orthophosphate (13.3% of total P) in poultry manure, suggesting that drying treatment caused the hydrolysis of some organic P to orthophosphate in dairy manure, but less recovery of orthophosphate in poultry manure. Comparison of these data indicates that the distribution patterns of major P forms in animal manure determined by the two methods were similar. Researchers can utilize the method that best fits their specific research goals or use both methods to obtain a full spectrum of manure P characterization.     

Caution needed in pretreatment of sediments for refining phosphorus-31 nuclear magnetic resonance analysis: results from a comprehensive assessment of pretreatment with ethylenediaminetetraacetic acid

Pretreatment with chemicals such as ethylenediaminetetraacetic acid (EDTA) is often used to improve the analysis of sediment P with solution P-31 nuclear magnetic resonance spectroscopy (35P-NMR), but there is a lack of a comprehensive assessment of the methodology. In this study, the effects of EDTA pretreatment on sediment P extracted using a mixture of 0.25 mol L(-1) NaOH and 50 mmol L(-1) EDTA (NaOH-EDTA) were examined with 45 different sediments. The results showed that EDTA pre-extraction decreased the amount of P extracted by NaOH-EDTA when the concentration ratio of sediment Ca to the sum of sediment Fe and Al [Ca/(Fe+Al), on a wt/vol basis] was lower than 0.4. An increase in total extracted P, coupled with substantial increases in total extracted paramagnetic ions such as Fe and Mn, was observed for another group of sediments with Ca/(Fe+Al) > 0.5, possibly due to the matrix effect. Analysis of 16 representative sediments with 31P-NMR showed that orthophosphate diesters were substantially removed by EDTA pre-extraction for sediments with Ca/ (Fe+Al) between 0.4 and 0.7, reflecting a high risk posed by this pretreatment. Phosphorus diversity and concentration of individual P compounds were markedly improved for sediments with Ca/(Fe+Al) > 0.7, suggesting that EDTA pretreatment was particularly useful for 31P-NMR analysis of calcareous sediments. The present study showed that sediment properties played an important role in determining pretreatment effects. Caution is advised when applying pretreatment methods to different sediments.     

Phosphorus forms and chemistry in the soil profile under long-term conservation tillage: a phosphorus-31 nuclear magnetic resonance study

In many regions, conservation tillage has replaced conventional tilling practices to reduce soil erosion, improve water conservation, and increase soil organic matter. However, tillage can have marked effects on soil properties, specifically nutrient redistribution or stratification in the soil profile. The objective of this research was to examine soil phosphorus (P) forms and concentrations in a long-term study comparing conservation tillage (direct drilling, "No Till") and conventional tillage (moldboard plowing to 20 cm depth, "Till") established on a fine sandy loam (Orthic Humo-Ferric Podzol) in Prince Edward Island, Canada. No significant differences in total carbon (C), total nitrogen (N), total P, or total organic P concentrations were detected between the tillage systems at any depth in the 0- to 60-cm depth range analyzed. However, analysis with phosphorus-31 nuclear magnetic resonance spectroscopy showed differences in P forms in the plow layer. In particular, the concentration of orthophosphate was significantly higher under No Till than Till at 5 to 10 cm, but the reverse was true at 10 to 20 cm. Mehlich 3-extractable P was also significantly higher in No Till at 5 to 10 cm and significantly higher in Till at 20 to 30 cm. This P stratification appears to be caused by a lack of mixing of applied fertilizer in No Till because the same trends were observed for pH and Mehlich 3-extractable Ca (significantly higher in the Till treatment at 20 to 30 cm), reflecting mixing of applied lime. The P saturation ratio was significantly higher under No Till at 0 to 5 cm and exceeded the recommended limits, suggesting that P stratification under No Till had increased the potential for P loss in runoff from these sites.     

An examination of spin-lattice relaxation times for analysis of soil and manure extracts by liquid state phosphorus-31 nuclear magnetic resonance spectroscopy

Phosphorous (P)-31 nuclear magnetic resonance (NMR) spectroscopy is used in the analysis of P forms in extracts of soils and manures for environmental and agronomic purposes. Quantitative spectra require knowledge about spin-lattice relaxation times (T1) to ensure adequate delays between pulses. This paper determined T1 values of P forms in reconstituted (0.2 g in 0.7 mL(-1)) samples of freeze-dried 0.25 M NaOH plus 50 mM EDTA extracts of eight diverse soils (Aquept, Dystrochrept x 2, Hapludand, Rendoll, Udand, Haplostoll, and Orthod), three different manures (dairy cattle, deer, and sheep), and one epiphyte moss. Total concentrations in the reconstituted samples ranged from 5 to 175 mg Fe mL(-1), 2 to 62 mg Mn mL(-1), and 72 to 837 mg P mL(-1). Values of T1 for orthophosphate monoesters, orthophosphate diesters, and pyrophosphate varied from 0.42 to 1.69 s in soils and from 0.89 to 2.59 s in manures and the epiphyte. In contrast, T(1) for orthophosphate varied from 0.78 to 1.94 s in soils and 1.45 to 5.82 s in manures and the epiphyte. For quantitative 31P NMR, delay times should be three to five times the T1 value, translating to delays of 3 to 5 s for soils and up to 25 s for manures. If the required delay is too long then strategies such as adding paramagnetics could shorten T1, provided this does not increase line-broadening too much. A regression relationship was obtained between orthophosphate T1 values and the ratio of P concentration to Fe and Mn concentration on a w/v basis (r2= 0.97, P < 0.001), and between the T1 for all other compound classes and the ratio of P to Fe and Mn (r2= 0.70, P < 0.01). By combining measurement of Fe, Mn, and P in the reconstituted extract and these relationships, T1 can be estimated and the appropriate delay time used. If T1 is not considered and the delay time is too short, some peaks will be under- or over-represented and the relative distribution of P forms not quantitative.     

A novel technique for the pre-concentration and extraction of inositol hexakisphosphate from soil extracts with determination by phosphorus-31 nuclear magnetic resonance

Inositol hexakisphosphate (IP6) is often the dominant form of soil organic phosphorus (P), but is rarely investigated because of the analytical difficulties encountered in its extraction, separation, and detection in environmental samples. In particular, recent advances in the study of soil organic P with 31P nuclear magnetic resonance (NMR) have been of limited use for the study of IP6, because the technique does not discriminate between IP6 and other forms of P. This was addressed by developing a novel analytical procedure using the retentive properties of gel-filtration gels for IP6, which allows the combined selective extraction and pre-concentration of IP6 from soil extracts with determination by 31P NMR. While the technique is still in the developmental stage, the results demonstrate that the gel does not interfere with 31P NMR analysis and retains IP6 to concentrations well above those required to give clear spectral signals. The technique has considerable potential for application to the study of IP6 in soil extracts and water samples and, with development, could help to answer fundamental questions regarding the dynamics of organic P in the environment.     

Phosphorus in fresh and dry dung of grazing dairy cattle, deer, and sheep: sequential fraction and phosphorus-31 nuclear magnetic resonance analyses

Knowledge of phosphorus (P) fractions in dung of animals (dairy cattle, deer, sheep) grazing pasture is important for soil fertility and the potential for P transport in runoff and subsequent surface water quality deterioration. We used sequential fractionation and 31P nuclear magnetic resonance (NMR) spectroscopy to determine P forms in fresh and air-dried (to simulate field conditions during grazing) dung. Sheep dung was richest in P (8 g kg(-1)), and cattle dung poorest (5.5 g kg(-1)). Data for sequential fractionation indicated that most P was extractable by water (15-36%) and bicarbonate (36-45%) in fresh dung, and shifted toward recalcitrant, HCl (12-28%), and residual P forms (15-31%) with drying. Organic P concentration in dung was poor (maximum of 15% of total P), probably due to the poor concentration of phytate in pasture. The 31P NMR spectra of NaOH-EDTA extracts supported this by detecting a low concentration of monoesters (9-19% of total P in extracts), of which phytate is a major component. The 31P NMR data also showed that changes in organic P concentration with drying could be due to the degradation of diesters. Data indicate the decreasing bioavailability of dairy cattle, deer, and sheep dung with drying and the need to consider this effect with respect to P returns for soil fertility and the potential for runoff.     

A comparison of phosphorus speciation and potential bioavailability in feed and feces of different dairy herds using 31p nuclear magnetic resonance spectroscopy

An experiment was conducted to examine how potential phosphorus (P) bioavailability (inferred from speciation) differs in feed and feces collected in spring from four dairy herds representing different management systems: (i) total confinement with cows fed total mixed ration (TMR), (ii) total confinement with TMR plus P mineral supplement, (iii) a hybrid of confinement with TMR and pastoral grazing, and (iv) predominantly grazing with supplemental grains. A treatment was included that air dried feces to simulate conditions after dung deposition. Wet chemical techniques and solution (31)P nuclear magnetic resonance spectroscopy ((31)P-NMR) were used to identify P concentrations and compounds present in water (a surrogate for P in overland flow), dilute acid (0.012 M HCl, an estimate of P utilization by cattle), or NaOH-EDTA (a solution that maximizes the organic P extraction) extracts of feed and feces. In general, P concentration in feces paralleled P in feed. Air drying feces decreased water-extractable P by 13 to 61% largely due to a decrease in orthophosphate, whereas NaOH-EDTA-extractable P increased by 18 to 48%. Analysis of dilute HCl was unsuccessful due to orthophosphate precipitation when pH was adjusted to 12 for (31)P-NMR. In water extracts, more P was in bioavailable diester-P forms, undetectable by colorimetry, than in NaOH-EDTA extracts. In feed, orthophosphate dominated (46-70%), but myo-IHP varied with feed (<10% in forage samples but 43% in a TMR sample). The proportion of myo-IHP decreased in feces compared with feed via mineralization but decreased less in systems with a greater proportion of available P input (e.g., orthophosphate and phospholipids). Feed and drying effect the concentrations and forms of P in feces and their potential impact on soil and water quality. Although bioavailable P in feces from pasture-based and confined systems can be similar in spring, dung-P is distributed on a lower kg P ha(-1) rate in grazing systems. The best method to mitigate P loss from feces is to decrease P in feed.     

Analysis of potentially mobile phosphorus in arable soils using solid state nuclear magnetic resonance

In many intensive agroecosystems continued inputs of phosphorus (P) over many years can significantly increase soil P concentrations and the risk of P loss to surface waters. For this study we used solid-state 31P nuclear magnetic resonance (NMR) spectroscopy, high-power decoupling with magic angle spinning (HPDec-MAS) NMR, and cross polarization with magic angle spinning (CP-MAS) NMR to determine the chemical nature of potentially mobile P associated with aluminum (Al) and calcium (Ca) in selected arable soils. Three soils with a range of bicarbonate-extractable Olsen P concentrations (40-102 mg P kg(-1)) were obtained from a long-term field experiment on continuous root crops at Rothamsted, UK, established in 1843 (sampled 1958). This soil has a threshold or change point at 59 mg Olsen P kg(-1), above which potentially mobile P (as determined by extraction with water or 0.01 M CaCl2) increases much more per unit increase in Olsen P than below this point. Results showed that CaCl2 and water preferentially extracted Al-P and Ca-P forms, respectively, from the soils. Comparison among the different soils also indicated that potentially mobile P above the threshold was largely present as a combination of soluble and loosely adsorbed (protonated-cross polarized) P forms largely associated with Ca, such as monetite (CaHPO4) and dicalcium phosphate dihydrate (CaHPO4-2H2O), and some Al-associated P as wavellite. The findings of this study demonstrate that solid-state NMR has the potential to provide accurate information on the chemical nature of soil P species and their potential mobility.     

Solid-state nitrogen-15 nuclear magnetic resonance analysis of biologically reduced 2,4,6-trinitrotoluene in a soil slurry remediation

Soil contaminated with 2,4,6-trinitrotoluene (TNT) and spiked with [14C]- and [15N3]-TNT was subjected to an anaerobic-aerobic soil slurry treatment and subsequently analyzed by radiocounting and solid-state 15N nuclear magnetic resonance (NMR) spectroscopy. This treatment led to a complete disappearance of extractable radioactivity originating from TNT and almost all of the radioactivity was recovered in the insoluble soil fraction. As revealed by solid-state 15N NMR, a major fraction of partially reduced metabolites of TNT was immobilized into the soil during the early stage of the anaerobic treatment, although some of the compounds (i.e., aminodinitrotoluenes and azoxy compounds) were extractable by methanol. Considerable 15N intensity was assigned to condensation products of TNT metabolites. A smaller signal indicated the formation of azoxy N. This signal and the signal for nitro groups were not observed at the end of the anaerobic phase, revealing further reduction and/or transformation of their corresponding compounds. An increase of the relative proportion of the condensation products occurred with increasing anaerobic incubation. Aerobic incubation resulted in a further decrease of aromatic amines, presumably due to oxidative transformations or their involvement in further condensation reactions. The results of the study demonstrate that the anaerobic-aerobic soil slurry treatment represents an efficient strategy for immobilizing reduced TNT in soils.     

Comparative analysis of partial structures of a peat humic and fulvic acid using one- and two-dimensional nuclear magnetic resonance spectroscopy

Nuclear magnetic resonance (NMR) resonance integrals obtained from one-dimensional NMR spectra provide semiquantitative contents of humic constituents with limited resolution in structural detail. When supplemented by connectivity information available from homo- and heteronuclear two-dimensional NMR spectra a more reliable assignment of humic substructures becomes available. This is demonstrated with a comparative one- and two-dimensional NMR analysis of a fulvic and a humic acid obtained from Eriophorum peat. An example of a detailed analysis of the proton chemical shift region normally attributed to carbohydrates shows substantial contributions from amino acids, amino and desoxy sugars, and highly oxidized aliphatic chains of intermediate length. The very good resolution of structural detail by a combined analysis of all NMR spectra shows that the effect of the fractionation procedure on the composition and chemical structure of humic materials is very significant. The comparison of the partial structures comprising humic acid (HA) and fulvic acid (FA) of the peat humic materials studied indicates that FA is diagenetically downstream of HA, favoring the biopolymer degradation (BD) model of humification.     

Studying organic matter molecular assemblage within a whole organic soil by nuclear magnetic resonance

This work shows the applicability of two-dimensional (2D) (1)H-(13)C heteronuclear correlation (HETCOR) nuclear magnetic resonance (NMR) spectroscopy to the characterization of whole soils. A combination of different mixing times and cross polarization (CP) methods, namely Lee-Goldberg (LG)-CP and Ramp-CP are shown to afford, for the first time, intra- and inter- molecular connectivities, allowing for molecular assemblage information to be obtained on a whole soil. Our results show that, for the brackish marsh histosol under study, two isolated domains could be detected. The first domain consists of O-alkyl and aromatic moieties (lignocellulose material), while the second domain is comprised of alkyl type moieties (cuticular material). The role of these domains is discussed in terms of hydrophobic organic compound sorption within soil organic matter (SOM), including the possible effects of wetting and drying cycles.     

Stray field nuclear magnetic resonance of soil water: development of a new, large probe and preliminary results

Development, characterization, and preliminary results of a recent technique capable of local measurements of pore-size distribution by a spatially resolved low resolution nuclear magnetic resonance (NMR) technique are described. Potential environmental uses include studying the change in pore-size distribution caused by surface compaction, which influences surface runoff, and obtaining information on the physical state of non-aqueous compounds in porous materials, which should aid the selection of appropriate soil remediation methods. Stray field (STRAFI) imaging is an NMR technique that allows distortion-free imaging of materials with short NMR relaxation times. The sample is placed in the strong axial fringe field gradient of a superconducting NMR magnet. We report on a new, unique, large 5-cm-diameter STRAFI probe, and its use for three preliminary test cases: water in ceramics of known pore size, paraffin wax and oil in sandstone rock, and water in soil at different matric potentials. The imaging is confined to one dimension with a spatial resolution of the order of 100 microm for protons. The optimum position for imaging occurs at 2.62 T and a gradient of 12.1 T/m. Water relaxation decay curves can be measured at any position in the 8-cm-long sample. These curves are decomposed into a series of terms each corresponding to a different pore size. Preliminary results show continuum fits to decay curves for a soil drained to three different matric potentials. Such information will be useful for interpreting water retention curves and will lead to understanding of the behavior of fluids in the vadose zone.     

Advanced solid-state carbon-13 nuclear magnetic resonance spectroscopic studies of sewage sludge organic matter: detection of organic "domains"

Two novel solid-state 13C nuclear magnetic resonance (NMR) spectroscopic techniques, PSRE (proton spin relaxation editing) and RESTORE [Restoration of Spectra via T(CH) and T(1rho)H (T One Rho H) Editing], were used to provide detailed chemical characterization of the organic matter from six Australian sewage sludges. These methods were used to probe the submicrometer heterogeneity of sludge organic matter, and identify and quantify spatially distinct components. Analysis of the T1H relaxation behavior of the sludges indicated that each sludge contained two types of organic domains. Carbon-13 PSRE NMR subspectra were generated to determine the chemical nature of these domains. The rapidly relaxing component of each sludge was rich in protein and alkyl carbon, and was identified as dead bacterial material. The slowly relaxing component of each sludge was rich in carbohydrate and lignin structures, and was identified as partly degraded plant material. The bacterial domains were shown, using the RESTORE technique, to also have characteristically rapid T(1rho)H relaxation rates. This rapid T(1rho)H relaxation was identified as the main cause of underrepresentation of these domains in standard 13C cross polarization (CP) NMR spectra of sludges. The heterogeneous nature of sewage sludge organic matter has implications for land application of sewage sludge, since the two components are likely to have different capacities for sorbing organic and inorganic toxicants present in sewage sludge, and will decompose at different rates.     

Bridging the gaps for global sustainable development: A quantitative analysis

Global human progress occurs in a complex web of interactions between society, technology and the environment as driven by governance and infrastructure management capacity among nations. In our globalizing world, this complex web of interactions over the last 200 years has resulted in the chronic widening of economic and political gaps between the haves and the have-nots with consequential global cultural and ecosystem challenges. At the bottom of these challenges is the issue of resource limitations on our finite planet with increasing population. The problem is further compounded by pleasure-driven and poverty-driven ecological depletion and pollution by the haves and the have-nots respectively. These challenges are explored in this paper as global sustainable development (SD) quantitatively; in order to assess the gaps that need to be bridged.Although there has been significant rhetoric on SD with very many qualitative definitions offered, very few quantitative definitions of SD exist. The few that do exist tend to measure SD in terms of social, energy, economic and environmental dimensions. In our research, we used several human survival, development, and progress variables to create an aggregate SD parameter that describes the capacity of nations in three dimensions: social sustainability, environmental sustainability and technological sustainability. Using our proposed quantitative definition of SD and data from relatively reputable secondary sources, 132 nations were ranked and compared.Our comparisons indicate a global hierarchy of needs among nations similar to Maslow's at the individual level. As in Maslow's hierarchy of needs, nations that are struggling to survive are less concerned with environmental sustainability than advanced and stable nations. Nations such as the United States, Canada, Finland, Norway and others have higher SD capacity, and thus, are higher on their hierarchy of needs than nations such as Nigeria, Vietnam, Mexico and other developing nations. To bridge such gaps, we suggest that global public policy for local to global governance and infrastructure management may be necessary. Such global public policy requires holistic development strategies in contrast to the very simplistic north–south, developed–developing nations dichotomies.     

Relating soil phosphorus to dissolved phosphorus in runoff: a single extraction coefficient for water quality modeling

Phosphorus transport from agricultural soils contributes to eutrophication of fresh waters. Computer modeling can help identify agricultural areas with high potential P transport. Most models use a constant extraction coefficient (i.e., the slope of the linear regression between filterable reactive phosphorus [FRP] in runoff and soil P) to predict dissolved P release from soil to runoff, yet it is unclear how variations in soil properties, management practices, or hydrology affect extraction coefficients. We investigated published data from 17 studies that determined extraction coefficients using Mehlich-3 or Bray-1 soil P (mg kg(-1)), water-extractable soil P (mg kg(-1)), or soil P sorption saturation (%) as determined by ammonium oxalate extraction. Studies represented 31 soils with a variety of management conditions. Extraction coefficients from Mehlich-3 or Bray-1 soil P were not significantly different for 26 of 31 soils, with values ranging from 1.2 to 3.0. Extraction coefficients from water-extractable soil P were not significantly different for 17 of 20 soils, with values ranging from 6.0 to 18.3. The relationship between soil P sorption saturation and runoff FRP (microg L(-1)) was the same for all 10 soils investigated, exhibiting a split-line relationship where runoff FRP rapidly increased at P sorption saturation values greater than 12.5%. Overall, a single extraction coefficient (2.0 for Mehlich-3 P data, 11.2 for water-extractable P data, and a split-line relationship for P sorption saturation data) could be used in water quality models to approximate dissolved P release from soil to runoff for the majority of soil, hydrologic, or management conditions. A test for soil P sorption saturation may provide the most universal approximation, but only for noncalcareous soils.     

A practical methodology for information fusion in presence of uncertainty: application to the analysis of a nuclear benchmark

This work is devoted to some methodological developments on information fusion in presence of uncertainty and their application in the frame of the BEMUSE Programme. In nuclear safety studies, different uncertainty analyses using different codes and implying different experts are generally performed. It is then useful to define formal methods to combine all these information sources in order to improve the reliability of the expertise process and especially to detect possible conflicts (if any) between the sources. Starting from the IRSN methodology already introduced in Destercke and Chojnacki (Nucl Eng Des 238(9):2484–2493, 2008), this paper presents a more convenient reformulation of its construction to allow its use by engineers. It is then applied to analyse the results coming from the BEMUSE Programme.     

A quantitative integrated evaluation of sustainable development of mineral resources of a mining city: a case study of Huangshi,Eastern China

It is generally considered that the non-renewable nature of mineral resources will make them gradually depleted over time. However, in the perspective of development availability of mineral resources in a long-term depends not only on their currently available amounts but also on future potential mineral resources (e.g. those undiscovered and low-grade ores) and substitutive renewable resources. In addition, it is influenced by factors like technology and capital. These factors interact with each other. As a result, it is possible to make the sustainable development of mineral resources by appropriate coordination between these factors. A new concept of Degree of Sustainable Development of Mineral Resources (DSDMR) and its conceptual model are proposed in this paper in the viewpoints of system science and sustainable development to evaluate the ability of sustainable development of mineral resources for a mining city. DSDMR refers to the ability of meeting needs of present and future generations for mineral resources by their logical distribution and substitution. An indicator system and a fuzzy integrated judgment model, which involve factors of resources, economy, society, environments and intelligence, are presented. They are used to evaluate DSDMR of Huangshi city, which is the most ancient and yet one of the most important mining cities producing iron and copper in China.