Resource utilization for decorating in three intertidal majid crabs (Brachyura: Majidae)

 For three spider crabs (Tiarinia cornigera, Micippaplatipes and Pugettia quadridens quadridens), patterns of algal utilization for decorating were compared with the dynamics of algae on an intertidal rocky shore reef where the crabs co-occurred. T. cornigera and P. quadridens quadridens were most abundant from autumn to spring when the dominant algae (Boodleacoacta, Sargassum hemiphyllum, S. thunbergii and Corallina pilulifera) occurred in high coverage, while M. platipes was most abundant from spring to autumn. Monthly change of algae used for decorating was not correlated with algae growing in the crab habitat for T. cornigera, but for M. platipes, it was positively correlated for two algal species, and for P. quadridens quadridens, negatively correlated for one algal species. Each species of the spider crabs used some algal species preferentially for decoration. Decorating preference experiments conducted in the laboratory showed that M. platipes and P. quadridens quadridens exhibited similar preference to their algal utilization in the field, whereas for T. cornigera, algal preference in the experiment differed from utilization in the field. Comparisons between materials used for decoration and gut contents revealed that T. cornigera and M. platipes used algal species differently for decorating and feeding, while P. quadridens quadridens used the same algal species for both decorating and feeding. Different tactics for camouflage are discussed in terms of algal utilizations by the three majid species. Received: 25 September 1999 / Accepted: 22 June 2000     

Anaerobic biodegradation of 4-alkylphenols in a paddy soil microcosm supplemented with nitrate

Anaerobic degradation of phenol, p-cresol, 4-n-propylphenol (n-PP), 4-i-propylphenol (i-PP), 4-n-butylphenol (n-BP) and 4-sec-butylphenol (sec-BP) was observed in a paddy soil supplemented with nitrate. We detected the metabolites 4′-hydroxypropiophenone (HPP) from n-PP, 4-i-propenylphenol from i-PP, and 4-(1-butenyl)phenol and 4′-hydroxybutyrophenone (HBP) from n-BP. Compared with the original soils, Betaproteobacteria became predominant in the microcosm during the degradation of phenol and p-cresol whereas no remarkable change was observed in the community degrading propylphenols and butylphenols. The microcosm, however, did not degrade 4-t-butylphenol (t-BP), 4-t-octylphenol (t-OP) and 4-n-octylphenol (n-OP). Paddy soil supplemented with sulfate or iron (III) as electron acceptors did not degrade phenol and 4-alkylphenols with the exception of the degradation of p-cresol in sulfate-reducing conditions. It was demonstrated for the first time that anaerobic microbial degradation of alkylphenols, in a paddy soil supplemented with nitrate as an electron acceptor, occurred via oxidation of the alpha carbon in the alkyl chain.     

Analysis of branched-chain fatty acids in humic substances as indices for compost maturity by pyrolysis–gas chromatography/mass spectrometry with tetramethylammonium hydroxide (TMAH-py–GC/MS)

Parameters that affect the degree of humification for humic substances (HSs) are deeply related to the maturity of the compost. In general, the matured composts contain HSs with a higher degree of humification. In addition, microbial activities during composting are also one of the indices for compost maturation. Branched-chain fatty acids are metabolites as the result of microbial activities in a soil environment. Such branched-chain fatty acids, regarded as humic precursors, are incorporated into HSs during the composting process. To determine whether branched-chain fatty acids in HSs can be used as biomarkers during composting processes or not, HSs were extracted from three types of composts with the different maturation, and the branched-chain fatty acids in the HSs were analyzed by pyrolysis–gas chromatography/mass spectrometry with tetramethylammonium hydroxide (TMAH-py–GC/MS). HSs with a higher degree of humification (higher aromaticity and lower molecular weight) contained higher levels of branched-chain fatty acids. These results show that branched-chain fatty acids in HSs from matured compost samples can be used as biomarkers, which indicate the history of microbial activities during overall composting process.     

Development of a testing method for asbestos fibers in treated materials of asbestos containing wastes by transmission electron microscopy

Appropriate treatment of asbestos-containing wastes is a significant problem. In Japan, the inertization of asbestos-containing wastes based on new treatment processes approved by the Minister of the Environment is promoted. A highly sensitive method for testing asbestos fibers in inertized materials is required so that these processes can be approved. We developed a method in which fibers from milled treated materials are extracted in water by shaking, and are counted and identified by transmission electron microscopy. Evaluation of this method by using asbestos standards and simulated slag samples confirmed that the quantitation limits are a few million fibers per gram and a few μg/g in a sample of 50 mg per filter. We used this method to assay asbestos fibers in slag samples produced by high-temperature melting of asbestos-containing wastes. Fiber concentrations were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10^?6 f/g. Because the evaluation of treated materials by TEM is difficult owing to the limited amount of sample observable, this testing method should be used in conjunction with bulk analytical methods for sure evaluation of treated materials.     

Source-specific sewage pollution detection in urban river waters using pharmaceuticals and personal care products as molecular indicators

Environmental Science and Pollution Research - Source-specific elucidation of domestic sewage pollution caused by various effluent sources in an urban river water, as conducted for this study,...     

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solid electrode

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solidelectrode was studied. As solid electrodes, carbon cloth (CC), carbon felt (CF) and titanium mesh were used, and palladium was plated on solid electrodes by either electrolytic or electroless method. On each electrode with Pd, chlorophenols were qualitatively dechlorinated to phenol, while they were entirely intact on electrodes without Pd. Moreover, neither base electrode nor plating method significantly affected the activity of Pd as far as it was sufficiently loaded on the electrode. Based on the results in the experiments using one electrode repeatedly, Pd catalyst proved to possess a satisfactory duarability under the present condition. It was suggested that the reactive species responsinble for the dechlorination of chlorophenols could be formed during preliminary electrolysis. Thus, (Pd)_x-H resulting from the adsorption of electrogenerated hydrogen on metallic Pd might be assumed most probable.     

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solid electrode

Electroreductive dechlorination of chlorophenols with Pd catalyst supported on solidelectrode was studied. As solid electrodes, carbon cloth (CC), carbon felt (CF) and titanium mesh were used, and palladium was plated on solid electrodes by either electrolytic or electroless method. On each electrode with Pd, chlorophenols were qualitatively dechlorinated to phenol, while they were entirely intact on electrodes without Pd. Moreover, neither base electrode nor plating method significantly affected the activity of Pd as far as it was sufficiently loaded on the electrode. Based on the results in the experiments using one electrode repeatedly, Pd catalyst proved to possess a satisfactory duarability under the present condition. It was suggested that the reactive species responsinble for the dechlorination of chlorophenols could be formed during preliminary electrolysis. Thus, (Pd)_x-H resulting from the adsorption of electrogenerated hydrogen on metallic Pd might be assumed most probable.     

The cost of stratospheric climate engineering revisited

Stratospheric aerosol injection (SAI) has been receiving increasing attention as a possible option for climate engineering. Its direct cost is perceived to be low, which has implications for international governance of this emerging technology. Here, we critically synthesize previous estimates of the underlying parameters and examine the total costs of SAI. It is evident that there have been inconsistencies in some assumptions and the application of overly optimistic parameter values in previous studies, which have led to an overall underestimation of the cost of aircraft-based SAI with sulfate aerosols. The annual cost of SAI to achieve cooling of 2 W/m² could reach US$10 billion with newly designed aircraft, which contrasts with the oft-quoted estimate of “a few billion dollars.” If existing aircraft were used, the cost would be expected to increase further. An SAI operation would be a large-scale engineering undertaking, possibly requiring a fleet of approximately 1,000 aircraft, because of the required high altitude of the injection. Therefore, because of its significance, a more thorough investigation of the engineering aspects of SAI and the associated uncertainties is warranted.     

Electrostatic hazards of charging of bedclothes and ignition in medical facilities

We investigated the charge generated on bedclothes (cotton and polyester) during bedding exchange with different humidities and the ignitability of an alcohol-based hand sanitizer (72.3 mass% ethanol) due to static spark with different temperatures to identify the hazards of electrostatic shocks and ignitions occurring previously in medical facilities. The results indicated that charging of the polyester bedclothes may induce a human body potential of over about 10?kV, resulting in shocks even at a relative humidity of 50%, and a human body potential of higher than about 8?kV can cause a risk for the ignition of the hand sanitizer. The grounding of human bodies via footwear and flooring, therefore, is essential to avoid such hazards (or to reduce such risks).