分形数学在环境问题评价中的某些应用     

西姆.  HM  叶兴茂 《国土资源信息化》1999,(9):15-18

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Pore water transport of enterococci out of beach sediments     

Phillips MC  Solo-Gabriele HM  Reniers AJ  Wang JD  Kiger RT  Abdel-Mottaleb N 《Marine pollution bulletin》2011,62(11):2293-2298

Enterococci are used to evaluate the safety of beach waters and studies have identified beach sands as a source of these bacteria. In order to study and quantify the release of microbes from beach sediments, flow column systems were built to evaluate flow of pore water out of beach sediments. Results show a peak in enterococci (average of 10% of the total microbes in core) released from the sand core within one pore water volume followed by a marked decline to below detection. These results indicate that few enterococci are easily removed and that factors other than simple pore water flow control the release of the majority of enterococci within beach sediments. A significantly larger quantity and release of enterococci were observed in cores collected after a significant rain event suggesting the influx of fresh water can alter the release pattern as compared to cores with no antecedent rainfall.  相似文献   

日本神户地震前地下水氡异常     

康瑞清  何钧 《地震科技情报》1996,(10):23-24

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岩性对南加州地震深度的控制     

Magis.  H 康瑞清 《世界地震译丛》1997,(4):6-9

南加州地震震源深度的分布表明,具有片岩基底的地区较具有其他类型基底岩石地区的最大震源深度浅(其深度在4～10km)。与其他基底岩石的矿物相比,片岩中的主要矿物塑化所需的温度较低,因而在深度较浅处塑化。岩性的水平向变化将控制未来潜在地震震源深度范围(乃至震级)。这种深度范围可以通过目前的背景地震活动性的深度来确定。  相似文献   

天然和人造石墨粉的市场动态     

Ridd.  HM 陆季萍 《江苏地质科技情报》1996,(5):28-28

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Correlation between the level of the potential biomarker, heat-shock protein, and the occurrence of DNA damage in the dab, Limanda limanda: a field study in the North Sea and the English Channel     

Schröder HC  Batel R  Hassanein HM  Lauenroth S  Jenke H  Simat T  Steinhart H  Müller WE 《Marine environmental research》2000,49(3):201-215

In the present study, heat-shock protein of M(r) 70 kDa (HSP70), a marker of cellular stress response, was validated as a potential biomarker under field conditions. The dab, Limanda limanda (female, size > or = 25 cm, spawning maturity stage 2) was used as the indicator organism. The data on HSP level were correlated with the occurrence of DNA damage, measured in the same specimens of L. limanda, to prove the usefulness of the method. The area under investigation was the North Sea. Four locations were selected: station N01, close to Heligoland, in the North Sea; station N04 at the Dogger Bank; station N06 at the Firth of Forth; and station G08 in the English Channel. Ten animals from each location were selected and their livers used for the experiments. The results show that the highest levels of HSP70 (consisting of two forms of M(r) 75 and 73 kDa) were in fish from station N04, while low values were measured in livers from L. limanda collected at station N01. Intermediate levels were seen in the animals from the two other locations. By application of a novel technique, it was found that the extent of DNA damage (single-strand breaks and alkaline labile sites) in fish liver parallels the levels of both HSP70 forms. Our results suggest that L. limanda may be a useful bioindicator and heat-shock proteins, a useful biomarker for monitoring of environmental pollution.  相似文献   

Influence of sample manipulation on contaminant flux and toxicity at the sediment-water interface   总被引：1，自引：0，他引：1  

Anderson BS  Hunt JW  Phillips BM  Fairey R  Puckett HM  Stephenson M  Taberski K  Newman J  Tjeerdema RS 《Marine environmental research》2001,51(3):191-211

Toxicities of sediments from San Diego and San Francisco Bays were compared in laboratory experiments using sea urchin (Strongylocentrotus purpuratus) embryos exposed to pore water and at the sediment-water interface (SWI). Toxicity was consistently greater to embryos exposed at the SWI to intact (unhomogenized) sediment samples relative to homogenized samples. Measurement of selected trace metals indicated considerably greater fluxes of copper, zinc, and cadmium into overlying waters of intact sediment samples. Inhibition of sea urchin embryo development was generally greater in sediment pore waters relative to SWI exposures. Pore water toxicity may have been due to elevated unionized ammonia concentrations in some samples. The results indicate that invertebrate embryos are amenable to SWI exposures, a more ecologically relevant exposure system, and that sediment homogenization may create artifacts in laboratory toxicity experiments.  相似文献   

究竟什么是D″?     

E.Garnero  M.Wysession  康瑞清 《世界地震译丛》2002,(3)

称为D双撇的地球深部层, 已被认真研究了50冬。新奇假说的提出新论文的发表如潮涌, 但模糊的图象仍使人置身云雾中。甚至在首次核弹试验之前, 像Gutenberg,Bullen和Dahm, 可能还有Dick,Harry和Tom等人, 就已对该新地层提出了疑问。是地热柱的发源地还是俯冲板片的坟墓?  相似文献   

The occurrence and distribution of pharmaceutical compounds in the effluents of a major sewage treatment plant in Northern Taiwan and the receiving coastal waters     

Fang TH  Nan FH  Chin TS  Feng HM 《Marine pollution bulletin》2012,64(7):1435-1444

The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3-46.8% and 3-18 days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.  相似文献   

Adjustment of benthic fauna following sediment disposal at a site with multiple stressors in Port Valdez, Alaska     

Blanchard AL  Feder HM 《Marine pollution bulletin》2003,46(12):1590-1599

The shallow subtidal macrobenthos at Port Valdez, Alaska, was examined to assess faunal adjustment following disposal of dredged sediments over a three-year period. Prior to sediment disposal, the infauna consisted of a relatively species-rich assemblage dominated by sessile polychaetes and bivalves. Six months after disposal, virtually all taxa present prior to dredging and disposal were rare or absent with opportunistic taxa dominant. Surveys performed 1.5 years after sediment disposal indicated faunal adjustment was in progress; large, sessile polychaetes and bivalves were still present in low numbers after 2.5 years. At one station, increasing organic enrichment by fish-wastes from adjacent processing plants resulted in a shift to a highly disturbed benthic assemblage. The trends in the faunal assemblage suggest that environmental conditions were still in a state of flux 2.5 years after the dredging event.  相似文献