Dairy farm effluent effects on urine patch nitrous oxide and carbon dioxide emissions

Dairy farm effluent (DFE) comprises animal feces, urine, and wash-down water collected at the milking shed. This is collected daily during the milking season and sprayed onto grazed dairy pastures. Urine patches in grazed pastures make a significant contribution to anthropogenic N(2)O emissions. The DFE could potentially mitigate N(2)O emissions by influencing the N(2)O to dinitrogen (N(2)) ratio, since it contains water-soluble carbon (WSC). Alternatively, DFE may enhance N(2)O emissions from urine patches. The application of DFE may also provide a substrate for the production of CO(2) in pasture soils. The effects of DFE on the CO(2) and N(2)O emissions from urine patches are unknown. Thus a laboratory experiment was performed where repeated DFE applications were made to repacked soil cores. Dairy farm effluent was applied at 0, 7, or 14 d after urine deposition. The urine was applied once on Day 0. Urine contained (15)N-enriched urea. Measurements of N(2)O, N(2), and carbon dioxide (CO(2)) fluxes, soil pH, and soil inorganic N concentrations were made. After 43 d the DFE had not mitigated N(2)O fluxes from urine patches. A small increase in the N(2)O flux occurred from the urine-treated soils where DFE was applied 1 wk after urine deposition. The amount of WSC applied in the DFE proved to be insignificant compared with the amount of soil C released as CO(2) following urine application. The priming of soil C in urine patches has implications for the understanding of soil C processes in grazed pasture ecosystems and the budgeting of C within these ecosystems.     

The measurement of experienced burnout

A scale designed to assess various aspects of the burnout syndrome was administered to a wide range of human services professionals. Three subscales emerged from the data analysis: emotional exhaustion, depersonalization, and personal accomplishment. Various psychometric analyses showed that the scale has both high reliability and validity as a measure of burnout.     

Extinction risk of the endemic vascular flora of Kauai,Hawaii, based on IUCN assessments

The International Union for Conservation of Nature's Red List of Threatened Species (IUCN Red List) is the world's most comprehensive information source on the global conservation status of species. Governmental agencies and conservation organizations increasingly rely on IUCN Red List assessments to develop conservation policies and priorities. Funding agencies use the assessments as evaluation criteria, and researchers use meta-analysis of red-list data to address fundamental and applied conservation science questions. However, the circa 143,000 IUCN assessments represent a fraction of the world's biodiversity and are biased in regional and organismal coverage. These biases may affect conservation priorities, funding, and uses of these data to understand global patterns. Isolated oceanic islands are characterized by high endemicity, but the unique biodiversity of many islands is experiencing high extinction rates. The archipelago of Hawaii has one of the highest levels of endemism of any floristic region; 90% of its 1367 native vascular plant taxa are classified as endemic. We used the IUCN's assessment of the complete single-island endemic (SIE) vascular plant flora of Kauai, Hawaii, to assess the proportion and drivers of decline of threatened plants in an oceanic island setting. We compared the IUCN assessments with federal, state, and other local assessments of Kauai species or taxa of conservation concern. Finally, we conducted a preliminary assessment for all 1044 native vascular plants of Hawaii based on IUCN criterion B by estimating area of occupancy, extent of occurrence, and number of locations to determine whether the pattern found for the SIE vascular flora of Kauai is comparable to the native vascular flora of the Hawaiian Islands. We compared our results with patterns observed for assessments of other floras. According to IUCN, 256 SIE vascular plant taxa are threatened with extinction and 5% are already extinct. This is the highest extinction risk reported for any flora to date. The preliminary assessment of the native vascular flora of Hawaii showed that 72% (753 taxa) is threatened. The flora of Hawaii may be one of the world's most threatened; thus, increased and novel conservation measures in the state and on other remote oceanic islands are urgently needed.     

Potential nitrogen constraints on soil carbon sequestration under low and elevated atmospheric CO2

The interaction between nitrogen cycling and carbon sequestration is critical in predicting the consequences of anthropogenic increases in atmospheric CO2 (hereafter, Ca). The progressive N limitation (PNL) theory predicts that carbon sequestration in plants and soils with rising Ca may be constrained by the availability of nitrogen in many ecosystems. Here we report on the interaction between C and N dynamics during a four-year field experiment in which an intact C3/C4 grassland was exposed to a gradient in Ca from 200 to 560 micromol/mol. There were strong species effects on decomposition dynamics, with C loss positively correlated and N mineralization negatively correlated with Ca for litter of the C3 forb Solanum dimidiatum, whereas decomposition of litter from the C4 grass Bothriochloa ischaemum was unresponsive to Ca. Both soil microbial biomass and soil respiration rates exhibited a nonlinear response to Ca, reaching a maximum at approximately 440 micromol/mol Ca. We found a general movement of N out of soil organic matter and into aboveground plant biomass with increased Ca. Within soils we found evidence of C loss from recalcitrant soil C fractions with narrow C:N ratios to more labile soil fractions with broader C:N ratios, potentially due to decreases in N availability. The observed reallocation of N from soil to plants over the last three years of the experiment supports the PNL theory that reductions in N availability with rising Ca could initially be overcome by a transfer of N from low C:N ratio fractions to those with higher C:N ratios. Although the transfer of N allowed plant production to increase with increasing Ca, there was no net soil C sequestration at elevated Ca, presumably because relatively stable C is being decomposed to meet microbial and plant N requirements. Ultimately, if the C gained by increased plant production is rapidly lost through decomposition, the shift in N from older soil organic matter to rapidly decomposing plant tissue may limit net C sequestration with increased plant production.     

Evaluation of ozone-nitrogen oxides-volatile organic compound sensitivity of Cincinnati, Ohio

Ambient concentrations of ozone (O3), nitrogen oxides (NOx), total reactive nitrogen (NOy), nitric acid (HNO3), and hydrogen peroxide (H2O2) were measured during September 2003 at an urban site of Cincinnati, OH. The aim of this study was two-fold: to investigate whether O3 formation in this population exposure-type site is NOx, sensitive or volatile organic compound (VOC) sensitive and to test the practicality of using two combined observational-based methods to identify the sensitivity of O3 formation in midlevel polluted locations. The evaluation of the indicator species: NOy, O3/NOy, O3/HNO3, H2O2/ HNO3, and O3/(estimated NOx reaction products), as well as the combined hypothesis testing analysis of the weekend/weekday (WE/WD) differences of 1-hr and 8-hr average maximum O3 and of the 6:00 a.m.-9:00 a.m. average nitric oxide and NOx concentrations, show evidence that Cincinnati is likely VOC sensitive. Average WE 1-hr and 8-hr maximum O3, as well as duration of WE O3 accumulation, were not lower than the corresponding WD levels in spite of the observed significant reduction in NO, emissions on WE, a typical situation in VOC-sensitive locations. The possibility that the seasonal transition from summer to autumn could have influenced the results was also investigated through an exploratory analysis of the afternoon O3 maximum/NOx measured and of the WE/WD differences of peak O3 and morning average NO and NO, concentrations observed at this site from June through September 2003. The results suggest that a VOC-sensitive chemistry regime dominated along the summer season. The findings of this study suggest that additional reductions in regional NO, emissions in Cincinnati, a potential nonattainment area under the 8-hr O3 standard, may cause an increase in local O3. Future strategies to reduce O3 in Southwest Ohio should be further evaluated carefully. The combination of observational-based methods might provide a consistent complementary approach in the identification of the NO,-VOC sensitive characteristics of mid-to-moderate polluted urban areas.     

Pyrolysis behavior of tire-derived fuels at different temperatures and heating rates

Pyrolytic product distribution rates and pyrolysis behavior of tire-derived fuels (TDF) were investigated using thermogravimetric analyzer (TGA) techniques. A TGA was designed and built to investigate the behavior and products of pyrolysis of typical TDF specimens. The fundamental knowledge of TGA analysis and principal fuel analysis are applied in this study. Thermogravimetry of the degradation temperature of the TDF confirms the overall decomposition rate of the volatile products during the depolymerization reaction. The principal fuel analysis (proximate and ultimate analysis) of the pyrolytic char products show the correlation of volatilization into the gas and liquid phases and the existence of fixed carbon and other compounds that remain as a solid char. The kinetic parameters were calculated using least square with minimizing sum of error square technique. The results show that the average kinetic parameters of TDF are the activation energy, E = 1322 +/- 244 kJ/mol, a pre-exponential constant of A = 2.06 +/- 3.47 x 10(10) min(-1), and a reaction order n = 1.62 +/- 0.31. The model-predicted rate equations agree with the experimental data. The overall TDF weight conversion represents the carbon weight conversion in the sample.     

Making a significant difference with burnout interventions: Researcher and practitioner collaboration

Burnout research over the past 30 years has yielded both knowledge and tools to apply to interventions at unit and organizational levels. Examples of innovative partnerships between researchers and practitioners point to the importance of multi‐level approaches in generating relevant and effective solutions to the burnout problem. Copyright © 2011 John Wiley & Sons, Ltd.     

Bewertung der potenziellen Grundwasserbelastung von deponierten Hochofengasschlämmen

Goal and Scope

Blast-furnace sludge is a waste originating from pig-iron production and contains contaminants such as lead, zinc, fluoride and cyanide assumably contaminating the groundwater by leaching.

Methods

We investigated the chemical composition of 27 samples of landfilled blast-furnace sludge in pore waters which were obtained by the centrifugation of fresh material and elution with water according to DIN 38414 part 4 (S 4).

Results

The pore waters as well as the eluates were neutral to alkaline (pH 7.3 to 10.7) and were dominated by alkali and alkaline-earth metals as well as sulphate and nitrate. The concentrations of all elements and compounds investigated were mostly clearly larger in the pore waters than in the eluates. The average concentrations of environmentally relevant constituents such as lead (0,18 mg?1), zinc (1,5 mg l?1), fluoride (10,6 mg l?1), and total cyanide (1.8 mg l?1) in the pore waters were distinctly larger than the inspection value of the German Federal soil Protection Ordinance for the pathway soil-groundwater. Lead, zinc, and total cyanide concentrations in the pore waters were largely underestimated by the eluates, as these concentrations were 70 to 90% lower in the eluates compared to the pore waters.

Conclusion

In the case of landfilled blast-furnace sludge, eluates according to DIN 38414 part 4 (S 4) provide low concentrations which are unrealistic to forecast concentrations in the seepage water.