Accumulation and mobility of zinc in soil amended with different levels of pig-manure compost

Applying manure compost not only results in zinc accumulation in the soil but also causes an increase in zinc mobility and enhances zinc leaching. In this study, the physical and chemical characteristics of zinc, zinc profiles, and zinc balance were investigated to characterise the fate of zinc in fields where the quality and amount of pig manure compost applied have been known for 13 years. Moreover, we determined zinc fractionation in both 0.1 mol L^?1HCl-soluble (mobile) and -insoluble (immobile) fractions. Adsorption of zinc in the soil was enhanced with increasing total carbon content following the application of pig manure compost. The 159.6 mg ha^?1 year^?1manure applied plot (triplicate) exceeded the Japanese regulatory level after only 6 years of applying pig manure compost, whereas the 53.2 mg ha^?1 year^?1 manure applied plot (standard) reached the regulatory level after 13 years. The zinc loads in the plots were 17.0 and 5.6 kg ha^?1 year^?1, respectively. However, 5.9 % and 17.2 % of the zinc loaded in the standard and the triplicate pig manure compost applied plots, respectively, were estimated to be lost from the plough layer. Based on the vertical distribution of mobile and immobile zinc content, a higher rate of applied manure compost caused an increase in the mobile zinc fraction to a depth of 40 cm. Although the adsorption capacity of zinc was enhanced following the application of pig manure compost, a greater amount of mobile zinc could move downward through the manure amended soil than through non manure-amended soil.     

Storage of CO2 in saline aquifers: Effects of gravity, viscous, and capillary forces on amount and timing of trapping

CO₂ can be effectively immobilized during CO₂ injection into saline aquifers by residual trapping – also known as capillary trapping – a process resulting from capillary snap-off of isolated CO₂ bubbles. Simulations of CO₂ injection were performed to investigate the interplay of viscous and gravity forces and capillary trapping of CO₂. Results of those simulations show that gas injection processes in which gravitational forces are weak compared to viscous forces (low gravity number N_gv) trap significantly more CO₂ than do flows with strong gravitational forces relative to the viscous forces (high N_gv). The results also indicate that over a wide range of gravity numbers (N_gv), significant fractions of the trapping of CO₂ can occur relatively quickly. The amount of CO₂ that is trapped after injection ceases is demonstrated to correlate with N_gv. For some simulated displacements, effects of capillary pressure and aquifer dip angle on the amount and the rate of trapping are reported. Trapping increases when effects of capillary pressure and aquifer inclination are included in the model. Finally we show that injection schemes such as alternating injection of brine and CO₂ or brine injection after CO₂ injection can also enhance the trapping behavior.     

Investigation of 1,4-dioxane originating from incineration residues produced by incineration of municipal solid waste

As a groundwater contaminant, 1,4-dioxane is of considerable concern because of its toxicity, refractory nature to degradation, and rapid migration within an aquifer. Although landfill leachate has been reported to contain significant levels of 1,4-dioxane, the origin of 1,4-dioxane in leachate has not been clarified until now. In this study, the origins of 1,4-dioxane in landfill leachate were investigated at 38 landfill sites and three incineration plants in Japan. Extremely high levels of 1,4-dioxane 89 and 340 microg l(-1), were detected in leachate from two of the landfill sites sampled. Assessments of leachate and measurement of 1,4-dioxane in incineration residues revealed the most likely source of 1,4-dioxane in the leachate to be the fly ash produced by municipal solid waste incinerators. Effective removal of 1,4-dioxane in leachate from fly ash was achieved using heating dechlorination systems. Rapid leaching of 1,4-dioxane observed from fly ash in a sequential batch extraction indicated that the incorporation of a waste washing process could also be effective for the removal of 1,4-dioxane in fly ash.     

Mutagenicity of anaerobic fenitrothion metabolites after aerobic biodegradation

Previous studies have revealed that the mutagenicity of fenitrothion increases during anaerobic biodegradation, suggesting that this insecticide's mutagenicity could effectively increase after it pollutes anaerobic environments such as lake sediments. To investigate possible changes to the mutagenicity of fenitrothion under aerobic conditions after it had already been increased by anaerobic biodegradation, batch incubation cultures were maintained under aerobic conditions. The mutagenicity, which had increased during anaerobic biodegradation, decreased under aerobic conditions with aerobic or facultative bacteria, but did not disappear completely in 22 days. In contrast, it did not change under aerobic conditions without bacteria or under continued anaerobic conditions. These observations suggest that the mutagenicity of anaerobically metabolized fenitrothion would not necessarily decrease after it arrives in an aerobic environment: this would depend on the presence of suitable bacteria. Therefore, fenitrothion-derived mutagenic compounds may pollute the water environment, including our drinking water sources, after accidental pollution of aerobic waters. Although amino-fenitrothion generated during anaerobic biodegradation of fenitrothion was the principal mutagen, non-trivial contributions of other, unidentified metabolites to the mutagenicity were also observed.     

Photocatalytic degradation of gaseous perchloroethylene: products and pathway

Batch photocatalytic degradation of 1000-ppm gaseous perchloroethylene (PCE) was conducted with UV irradiation such that nearly 100% was decomposed within 10 min. The main intermediate and final product were identified as trichloroacetylchloride (TCAC) and hydrogen chloride (HCl), respectively, and minor ones as dichloroacetic acid (DCAC), monochloroacetic acid (MCAC), carbon tetrachloride, chloroform, and phosgene. More than 90% of Cl- equivalent, i.e., the sum of the chlorine number in PCE, intermediates, and HCl, was compensated for during the time of PCE degradation; a result indicating that no other major chlorinated intermediates are present during the time of PCE degradation. In a similar experiment, 500 ppm of gaseous TCAC degraded into HCl within 3 h without producing DCAC or MCAC, where like PCE, more than 90% of Cl- equivalent, i.e., the sum of the chlorine number in TCAC and HCl, was compensated for during time of TCAC degradation. Accordingly, gaseous PCE is concluded to predominantly follow a degradation pathway of PCE --> TCAC --> HCl.     

Aqueous leaching of cattle manure incineration ash to produce a phosphate enriched fertilizer

Ash produced from the combustion of livestock manure contains large amounts of phosphorus (P), which is an important resource as a fertilizer. Some studies have extracted and recovered P from incinerated biomass ash using inorganic acid or alkaline agents, which produce wastewater that requires treatment and is expensive due to the cost of chemicals. Livestock manure ash contains not only P, but also water soluble salts, which could be a negative influence on plant growth and shall be preferably removed from the recovered fertilizer. In this study, we removed salinity from cattle manure incineration ash by simple aqueous leaching, while retaining the P content. The optimal condition was a 20 min leaching time at a liquid/solid (L/S) ratio of 10 mL g-ash^?1. Under this condition, over 90 % of Cl and 20 % of Na in the original ash was removed, while over 99 % of the P was retained in the leached residue. The leached residue met the fertilizer standard in Japan in terms of citrate soluble fertilizer components and contained few heavy metals. X-ray analyses of the ash indicated that Cl was mainly present as KCl in the original ash, while P was mainly present as Ca compounds in the ash.     

Microhabitat association in white-streaked grouper Epinephelus ongus: importance of Acropora spp.

Microhabitat associations are considered to be important for juvenile survivorship and growth of coral reef fishes. The aim of the study was to quantify microhabitat associations between juvenile and adult white-streaked grouper Epinephelus ongus, which supports important fisheries in coral reef areas. Underwater observations revealed that most juveniles were found in bottlebrush Acropora spp., staghorn Acropora spp. and coral rubble and there was a significant positive use of bottlebrush Acropora spp. and a significant negative use of coral rubble. For adults, most individuals were found in bottlebrush Acropora spp. and staghorn Acropora spp., and there was a significant positive use of staghorn Acropora spp. and significant negative use of coral rubble. A habitat choice experiment by using pre-settlement individuals revealed that both bottlebrush Acropora spp. and staghorn Acropora spp. were used as settlement sites, whereas coral rubble was rarely used as a settlement site. Results of the study suggest that juvenile and adult E. ongus showed significantly positive microhabitat associations with bottlebrush Acropora spp. and staghorn Acropora spp., respectively, in the field. Bottlebrush Acropora spp. has smaller inter-branch spaces than staghorn Acropora spp., which could drive patterns of microhabitat associations. In addition, post-settlement processes such as predation may influence the spatial distribution of juveniles. Because Acropora corals are very susceptible to coral bleaching, we predict that rising temperatures from climate change will negatively impact populations of E. ongus.     

Non-sterile simultaneous saccharification and fermentation of corn leaves and stalks to <Emphasis Type="SmallCaps">l</Emphasis>-lactic acid without external nutrient addition

Fermentation of lignocellulosic biomass requires auxiliary materials, including nutrients, to ensure the proliferation of microorganisms. Nutrients are usually inexpensive, but their contribution to the cost is considerable because of the very low prices of fermentation products, such as bio-ethanol. Using substances present in native lignocellulosic biomass as nutrients for fermentation was proposed and demonstrated. Leaves and stalks of corn plants were used as biomass, and nutrients were recovered as a nutrient solution by soaking them in water before alkaline peroxide pretreatment. Pretreated biomass and the nutrient solution derived from the same lot were used for non-sterile simultaneous enzymatic saccharification and thermophilic l-lactic acid fermentation (SSF). Using the nutrient solution in the saccharification step did not impact sugar recovery, and instead improved sugar yields because of the presence of eluted sugars in the solution. The l-lactic acid yield of 0.33 g g^?1 based on native biomass weight indicated that the nutrient solution functioned as a source of nutrients and sugars, especially as a source of essential phosphorus. Comparatively, autoclaved SSF yielded less or no l-lactic acid, indicating an apparent inhibitive effect derived from the nutrient solution on bacterial growth.     

Factors associated with prehospital death among traffic accident patients in Osaka City,Japan: A population-based study

Objective: Although it is important to assess the factors associated with traffic accident fatalities to decrease them as a matter of public health, such factors have not been fully identified.

Methods: Using a large-scale data set of ambulance records in Osaka City, Japan, we retrospectively analyzed all traffic accident patients transported to hospitals by emergency medical service personnel from 2013 to 2014. In this study, prehospital death was defined as that occurring at the scene or in the emergency department immediately after hospital arrival. We assessed prehospital factors associated with prehospital death due to traffic accidents by logistic regression models.

Results: This study enrolled 28,903 emergency patients involved in traffic accidents, of whom 68 died prehospital. In a multivariate model, elderly patients aged ≥75 years (adjusted odds ratio [AOR] = 4.34; 95% confidence interval [CI], 2.29–8.23), nighttime (AOR = 2.75; 95% CI, 1.65–4.70), and type of injured person compared to bicyclists such as pedestrians (AOR = 9.58; 95% CI, 5.07–17.99), motorcyclists (AOR = 2.75; 95% CI, 1.21–6.24), and car occupants (AOR = 2.98; 95% CI, 1.39–6.40) were significantly associated with prehospital death due to traffic accidents. In addition, the AOR for automobile versus nonautomobile as the collision opponent was 4.76 (95% CI, 2.30–9.88).

Conclusions: In this population, the factors associated with prehospital death due to traffic accidents were elderly people, nighttime, and pedestrian as the type of patient. The proportion of prehospital deaths due to traffic accidents was also high when the collision component was an automobile.     

Spawning migration and returning behavior of white-streaked grouper Epinephelus ongus determined by acoustic telemetry

White-streaked grouper (Epinephelus ongus) is an important fishery target that forms fish spawning aggregations (FSAs) at specific spawning grounds. The aims of the present study were to investigate migration behavior and returning behavior in terms of FSA using acoustic telemetry. Among the 30 specimens tracked, three types of movement pattern were observed: type 1, high site fidelity at the release area before the spawning period, migration to the spawning ground during the spawning period and return to the release area just after the spawning period (17 specimens); type 2, high site fidelity at the release area, disappearance from the area during the spawning period but was not detected at the spawning ground and return to the release area (8 specimens); and type 3, high site fidelity at the release area was observed before, during and after the spawning period (5 specimens). For the 17 specimens that were categorized into type 1, the dates of departure from their release area and the dates of return to the release area of males were, respectively, significantly earlier and later than those of females. The duration between the departure date and the return date (“duration away”) of males was significantly longer than that of females. The duration away tended to be positively related to the condition factor. All 25 specimens that were categorized as type 1 and type 2 showed returning behaviors to the release area.