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Behavior of di(2-ethylhexyl) phthalate discharged from domestic waste water into aquatic environment
The behavior of di(2-ethylhexyl) phthalate (DEHP) discharged from domestic waste water into river water, sediment and submerged aquatic vegetation was investigated. The concentrations of DEHP were found to be between 8-25 microg L(-1) in river water, 1,000-2,000 microg kg(-1) in sediment and less than 20-2,000 microg kg(-1) in submerged aquatic vegetation. The experiments performed in laboratory were on the biodegradation of DEHP in water and sediment, and also adsorption equilibrium of DEHP between water and sediment. The results obtained from the investigations made it clear that the high enrichment of DEHP from water to sediment was caused from not only its high adsorptive potential but also slow degradation in sediment. 相似文献
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Yamaguchi N Nakano M Takamatsu R Tanida H 《Journal of environmental radioactivity》2010,101(6):451-9983
The transformation of inorganic iodine (I− and IO3−) incubated in soils with varying amounts of organic matter (Andosols from the surface layer of an upland field and forest, as well as Acrisols from surface and subsurface layers of an upland field) was investigated by using the iodine K-edge X-ray absorption near-edge structure (XANES). After 60 d of reaction, both I− and IO3− were transformed into organoiodine in surface soils containing sufficient amounts of organic matter, whereas IO3− remained unchanged in the subsurface soil of Acrisols with low organic matter contents. Transformation of IO3− into organoiodine was not retarded when the microbial activity in soil was reduced by γ-ray irradiation, suggesting that microbial activity was not essential for the transformation of inorganic iodine into organoiodine. Soil organic matter has the ability to transform inorganic iodine into organoiodine. 相似文献
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Noriko Tamura 《Behavioral ecology and sociobiology》1995,36(6):377-386
The Formosan squirrel, Callosciurus erythraeus thaiwanensis, emitted different vocalizations in response to terrestrial and aerial predators and snakes. Each vocalization caused nearby individuals to adopt a different type of anti-predator behaviour. In mating bouts, males produced two types of loud calls: precopulatory calls, emitted before copulations, and postcopulatory calls, emitted after copulations. The latter continued for 17 min on average. The estrous female and other males attending the mating bouts stopped moving during the postcopulatory call, so that the calling male was able to tend the female without interruption. The sound characteristics of anti-terrestrial-predator and postcopulatory calls recorded in the captivity were compared, and none of the ten characters of duration and frequency measured differed between the two calls. Playback experiments also showed that responses to the sounds in two different contexts, escape behaviour and defensive immobility, did not differ. The similarity between anti-predator and postcopulatory calls is discussed with reference to the possibility of manipulation and other explanatory hypotheses. 相似文献
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The growth and production of the inshore marine copepod Pseudodiaptomus marinus was studied in the central part of the Inland Sea of Japan. The stage-specific growth rate was determined under controlled laboratory conditions by examining the length-weight relationship and development rates at various temperatures. The stage duration was short and constant from NII to CII, beyond which development was retarded. Males developed faster than females in CIV and CV. The specific growth rate was highest in copepodite stages followed by the nauplii and adult females (=egg production rate). The daily production of P. marinus was estimated from the stage-specific growth rate and stage-specific abundance in nature as the sum of the individual stages. The production changed seasonally with water temperature and population biomass. Daily production and biomass (P/B) ratios increased linearly with temperature. Total annual production was 20.7 mg C m-3 yr-1. 相似文献
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Kazuto Sazawa Yoshiki Furuhashi Noriko Hata Shigeru Taguchi Masami Fukushima 《毒物与环境化学》2013,95(3):472-482
A micro-scale algal growth inhibition (μ-AGI) test using a common micro-plate based fluorometric detection was used to demonstrate the effects of humic substances (HSs) on the toxicity of tetrabromobisphenol A (TBBPA) and its oxidative decomposition products 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,5-dibromohydroquinone (2,5-DBHQ), 2,6-dibromobenzoquinone (2,6-DBBQ), and 2,6-dibromophenol (2,6-DBP) to Pseudokirchneriella subcapitata. The EC50 values were: EC50(TBBPA) = 7 mg L?1, EC50(2,5-DBHQ) = 7 mg L?1, EC50(2,5-DBBQ) = 19 mg L?1, EC50(2,6-DBP) = 49 mg L?1, and EC50(2,6-DBBQ) = 13 mg L?1. The toxicity of the chemicals was slightly lower in the presence of HA. The toxicity of TBBPA decomposed by a biomimetic catalytic system consisting of iron (III) 5,10,15,20-tetrakis (p-sulfonatophenyl) porphyrin (Fe(III)-TPPS) and KHSO5 was also evaluated using P. subcapitata and Chlamydomonas reinhardtii. 相似文献
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Miyatake N Sakano N Murakami S Suna S Suzue T Hirao T 《Environmental monitoring and assessment》2011,181(1-4):525-530
We investigated the changes in temperatures in Takamatsu, Tadotsu and Osaka areas in Japan. Data of temperatures in Takamatsu (urban area: 1942-2009), Tadotsu (rural area: 1893-2009) and Osaka (metropolitan area: 1883-2009) areas around the Inland Sea in Japan was obtained from Japan Meteorological Agency. The changes in temperatures in three areas in Japan were analyzed and compared. By using data from 1942 to 2009, various parameters of temperatures were significantly correlated with years. The changes in mean temperature in August and in a year in Takamatsu area for 50 years were highest (August: 1.6°C, Year: 1.8°C) among three areas. In addition, correlation coefficient rate between years and the number of days over the level of 34°C in August in Takamatsu area was highest (r = 0.567, p < 0.0001). Parameters of temperatures were gradually increased with years in all three areas. The heat island effect in Takamatsu area was similar to Osaka area in Japan. 相似文献
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Distribution and morphology of zooxanthellae were investigated histologically and ultrastructurally in veligers and juveniles
of three giant clam species, Tridacna crocea, T. derassa, and T. squamosa. No zooxanthellal cells were associated with gametes. In veliger larvae, zooxanthellae were ingested and digested in the
stomach. Within several days after metamorphosis from veliger to a juvenile clam, the zooxanthellal tube, in which zooxanthellae
were packed, elongated from the stomach toward the mantle. Zooxanthellae in the tube appeared in a line, and we designated
the appearance of the lined zooxanthellae in the mantle of juvenile clams as the first sign of the establishment of symbiosis.
The zooxanthellal tubular system developed as the clams grew, particularly in the mantle margin, and then hypertrophied siphonal
tissue formed. In zooxanthellal tubes, zooxanthellae usually had intact ultrastructures suggesting that they were photosynthetically
active, while the stomach always contained degraded zooxanthellae that were probably discharged from the zooxanthellal tube.
Giant clams probably digest zooxanthellae directly, and ingest the secreted photosynthates from zooxanthellae. There may be
a selection mechanism to discharge unhealthy zooxanthellae from the mantle into the stomach. In addition to zooxanthellae,
digested diatoms and other unidentified digested materials in the stomach suggest that filter-feeding also contributes to
giant clam nutrition. 相似文献