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971.
The first incident of green oysters (Crassostrea gigas) was reported in Taiwan in the Charting coastal area in January, 1986 and mortality was reported three months later. the cause of the greened oysters was identified as copper pollution. the copper content of the green oysters was extremely high - 2100 ppm, 2225 ppm, and 4400 ppm dry weight, in January, 1986, February 1987, and January 1989, respectively. in this paper we summarize the seasonal and regional distributions of copper species (complexed by inorganic and organic ligands, labile and non-labile, polar and non-polar) and forms (dissolved and particulate) and the hydrographic and biomass parameters (mainly particulate organic carbon, chloropyll -α, adenosine triphosphate and primary production) in sea water in the Erhjin Chi coastal area. in general, high concentrations of particulate material (0.24 to 724 ppb) and non-labile organic copper (0.03 to 21.5 ppb) were observed. Low values of polar organic copper (<0.02 to 16.5 ppb) indicated that non-polar organic complexes (0.3 to 20.4 ppb) from man-made organic pollutants were the major complexes in the area studied. On the basis of this data, the cause of greening and mortality in oysters is evaluated in relation to the bioavailable copper (sum of particulate and labile copper) and copper assimilative capacity (detoxicant). Finally, the correlations between the species and forms of copper, hydrographic and biomass parameters are also discussed. 相似文献
972.
A study on the carbon dioxide exchange at the water-air interface in the Western Mediterranean Sea was carried out. the attention was focused on the mean air-sea flux estimations by radiocarbon profiles and bomb 14C concentration atmospheric data. Sampling techniques and analytical methods are reported; mass balance evaluations on data recorded during the MED'92 cruise are presented and discussed briefly. 相似文献
973.
Kurunthchalam Senthilkumar Naomasa Iseki Sunardi Seiichi Kasuga Takumi Takasuga Shigeki Masunaga 《毒物与环境化学》2013,95(4-6):121-132
Polychlorinated-dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and -dioxin-like polychlorinated biphenyls (DLPCBs) were determined in aquatic wildlife of Kasumigaura Lake (KUL), Japan from 1978 to 2001. Two plankton species elucidated several fold greater concentrations (2400–7800) than small tiger fish (310–6500), shrimp (160–1100), and three large fish namely, black bass (120–240), carp (94–120) and mullet (54) on pg/g fat. PCDD homologues were predominant accumulants with >68–<95% contribution and remaining was shared by PCDFs. Accumulation, non-ortho DLPCBs in plankton (3500–9200), shrimp (1600–8600) and small fish (2000–8800) and large fish (1300–3900) on ng/g fat basis were several orders magnitude greater than PCDD/DFs. The mono-ortho DLPCBs in large fish species were 23?000–83?000?ng/g fat and which it is accounted 94.3–95.9% the total dioxin-like PCBs accumulation. Temporal trends of PCDDs, PCDFs, non-ortho PCBs and TEQ in shrimp and small tiger fish were varied. The mullet had minimum toxic equivalency “TEQ” (14?pg?TEQ/g) followed by plankton Neomysis intermedia (25?pg?TEQ/g), small tiger fish (mean: 33, ranges 14–66?pg?TEQ/g), plankton Cyclopus vicinus (34?pg?TEQ/g), carp (mean: 35, ranges 32–38?pg?TEQ/g), shrimp (mean: 38, ranges 11–68?pg?TEQ/g) and black bass (mean: 59, ranges 38–79?pg?TEQ/g) on fat basis. In all the samples, PCDD was predominant TEQ contributor followed by PCDFs and DLPCBs. The contribution of mono-ortho DLPCBs to the total TEQ was 0.52–0.92 in large fish. 相似文献
974.
975.
ABSTRACTThis article contributes to efforts to validate a common set of parameters and principles of sustainable agriculture. Comparisons between alternative forms of sustainable agriculture and rural-to-urban community resilience are investigated. Conclusions are drawn between multiple sustainable/alternative agriculture systems and evaluated. A set of common baseline parameters and principles is proposed as a method of evolving a common structural framework for strengthening sustainability of agriculture and rural contexts. Concepts of rural-to-urban community sustainability are proposed, supporting sustainable agriculture contexts as rural and urban. In the twenty-first century, agriculture is becoming more diversified and less typified as a rural occupation. Urban agriculture is expanding as the need for fresh, affordable, accessible agriculture produce increases in urban areas. Evidence supports symbiotic relationships between sustainable agriculture and rural/urban communities, although some claim this relationship has not been clearly defined.This article investigates sustainable agriculture from two perspectives. We ask ‘what are common parameters and principles of the various forms of sustainable agriculture,’ and ‘why urban-to-rural context.’ Organic agriculture parameters and principles are proposed as a conceptual framework toward establishing baseline parameters and principles for sustainable agriculture. Best management parameters of urban and rural sustainable agriculture in the United States and the United Kingdom are examined for their potential to develop a strengthening framework of parameters and principles of agriculture and rural-to-urban sustainability. These results are compared and evaluated for their effectiveness in redefining current sustainable agriculture practices, and their value in strengthening sustainable agriculture symbiosis with rural-to-urban community systems. 相似文献
976.
利用SOS/umu测试方法鉴定沙颍河河水中的遗传毒性物质 总被引:1,自引:0,他引:1
采用HPLC分割导向的SOS/umu测试方法鉴定了沙颍河河水中的遗传毒性物质。当采用TA1535/pSK1002菌株测定HPLC分割的各馏分时,如果不经大鼠肝微粒体酶(S9)代谢活化,只有馏分F10显示遗传毒性,加入大鼠肝微粒体酶代谢活化后,馏分F10和馏分F15都显示有遗传毒性,说明河水中存在某些需经过大鼠肝微粒体酶代谢活化才能显示出遗传毒性的物质。当采用过量表达O-乙酰转移酶(O-AT),对芳香胺类物质和硝基芳烃化合物有特殊响应的NM2009菌株测定时,馏分F8、F9和F10均呈现遗传毒性;特别是对于馏分F10,用NM2009菌株测定的遗传毒性远高于原始菌,说明这3个馏分中都含有芳香胺类或硝基芳烃类物质。 相似文献
977.
Secondary copper production is one of the key polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) emission sources in China, but research and data on this issue are rare. In 2004, when the Stockholm Convention entered into force in China, PCDD/Fs emissions from secondary copper production contributed to 32.2% of the total release. In this paper, PCDD/Fs emission dynamics from secondary copper industry were discussed and cumulative risks were characterized. From 2004 to 2009, industrial policies played an indirect role in PCDD/Fs reduction, but its effects are still limited. The Yangtze River Delta, Pearl River Delta and central regions were among the top three of dioxin emissions from secondary copper production in China. Shanghai, Shandong, Zhejiang, and Jiangxi had comparatively higher accumulated risk and were recommended as the priority regions for promoting PCDD/Fs emission control in China. From 2009 to 2015, the PCDD/Fs emission dynamics in the secondary copper industry were presented through simulation. PCDD/Fs emission equations were established, resulting in the recommendation of control technology conversion rate at 30% for small scale smelters and 51%–57% for large and medium-sized enterprises in 2015. In conclusion, both indirect policy and direct control technology retrofitting should be integrated for more effective PCDD/Fs emission reduction in secondary copper industry. 相似文献
978.
以玉田县古玉煤焦化工有限公司焦化废水处理站工程为例,介绍气浮-A2/O2工艺处理高浓度焦化废水的运行效果及工艺参数。运行结果表明:气浮-A2/O2工艺对焦化废水具有理想的处理效果,当进水ρ(COD)<3 500 mg/L、ρ(酚)<700 mg/L、ρ(氰化物)<20 mg/L、ρ(NH3-N)<300 mg/L时,出水ρ(COD)<100 mg/L、ρ(酚)<0.5mg/L、ρ(氰化物)<0.5 mg/L、ρ(NH3-N)<15 mg/L,各项指标均达设计要求,满足熄焦工段的用水要求和排放标准。 相似文献
979.
980.
A/O法处理水产品加工废水 总被引:2,自引:2,他引:0
采用A/O工艺处理水产品加工废水,处理量为500 t/d,运行两年来,效果稳定,处理结果表明:对COD、BOD5和氨氮的去除率分别为94.7%、98.1%和86.4%,出水达到GB 8978—1996《污水综合排放标准》中的一级排放标准,且该工艺具有运行费用低、处理效果好、操作管理方便等一系列优点。 相似文献