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41.
通过田间定位试验,研究了石灰(L)、钙镁磷肥(G)、泥炭(P)、猪粪(M)、石灰 泥炭(L P)、石灰 猪粪(L M)、钙镁磷肥 泥炭(G P)、钙镁磷肥 猪粪(G M)等改良材料对新罗区特钢厂附近的重金属污染田的长期改良效应.结果表明:大部分处理可提高土壤的pH值、有机质含量,降低了土壤的有效锌含量,石灰 泥炭、钙镁磷肥 泥炭的改良效果要优于单施有机、中性化改良剂和其它处理,和对照相比,有效锌含量和糙米锌含量最高分别降低了59.2%、36.2%.  相似文献   
42.
The purpose of this study was to assess contaminated soil and groundwater for the urban redevelopment of a rapid transit railway and a new mega-shopping area. Contaminated soil and groundwater may interfere with the progress of this project, and residents and shoppers may be exposed to human health risks. The study area has been remediated after application of first remediation technologies. Of the entire area, several sites were still contaminated by waste materials and petroleum. For zinc (Zn) contamination, high Zn concentrations were detected because waste materials were disposed in the entire area. For petroleum contamination, high total petroleum hydrocarbon (TPH) and hydrocarbon degrading microbe concentrations were observed at the depth of 7 m because the underground petroleum storage tank had previously been located at this site. Correlation results suggest that TPH (soil) concentration is still related with TPH (groundwater) concentration. The relationship is taken into account in the Spearman coefficient (α).  相似文献   
43.
Dioxin-like polychlorinated biphenyls (DLPCBs) are ubiquitous persistent pollutants that cause adverse effects in many environmental organisms. DLPCBs in marine sediments can be absorbed by benthic organisms, bioaccumulate, and biomagnify through the food chain and threaten animal and human health. There are no reports of DLPCBs concentrations in the Zhanjiang Gulf seabed. This study was designed to investigate the concentration of DLPCBs in the Zhanjiang coastal sediment and histopathological changes in zebrafish (Diano rerio) embryos exposed to environmentally relevant concentrations of DLPCBs. Of the five sites selected, two sites TS and JSW contained DLPCBs at concentrations of 0.08 and 22.54 ng/g dry sediment, respectively. Two groups of zebrafish embryos were used. One group was exposed to 3.75, 7.5, 15, 30, and 60 mg/ml of DLPCBs extracted from the sediments sampled from the TS site and the second group to 4.375, 8.75, 17.5, 35, and 70 mg/ml of DLPCBs from JSW site from 0.75 h post-fertilization (hpf) to 96 hpf. The zebrafish exposed to 60 and 70 mg/ml of DLPCBs at 96 hpf displayed gross histopathological changes with cardiac lesions including pericardial edema being the most deleterious. Other changes observed were hydropic degeneration of gill filaments and hepatocytes, loss of intestinal folds, and uninflated swim bladder. It appears that only a few sites of the Zhanjiang gulf are contaminated with DLPCBs. This is the first report of histopathological changes in the gills, hepatocytes, intestines, heart, and the swim bladder in zebrafish embryos exposed to DLPCBs from a coastal sediment. Further studies with sampling at different stages of development are required to identify which organ/tissue is most sensitive to DLPCBs.  相似文献   
44.
以长春为例研究环境空气中TSP、PM_(10)和PM_(2.5)的相关性   总被引:2,自引:0,他引:2  
选取长春市解放大路与人民大街的交叉口为研究地点,分别进行TSP、PM10和PM2.5的采样和分析.然后利用相关系敷法和t检验对测定结果进行相关性分析,得到备元素的含量在三种污染物中的相关系敖:在TSP与PM10中为0.9349;在PM2.5与PM10中为0.8797;在TSP与PM2.5中为0.7824.得到各元素含量在三种污染物中的T检验统计值,在TSP与PM10中为0.90103;在PM2.5与PM10中为0.04745;在TSP与PM2.5中为0.047986.从分析结果可以看出,各元素含量在TSP与PM10中的相关性最好,在PM2.5与PM10中次之,研究结果为相关环境管理提供科学依据.  相似文献   
45.
46.
渭、洛河下游受三门峡水库回水淹没及影响,洪灾频繁。本文依据1902年8月惨重洪灾的实例,全面分析了洪水的特殊性和致灾因素,并从流域治理、水库水沙调度、防洪工程建设等方面提出了进一步减灾的措施。  相似文献   
47.
生物修复重金属污染土壤的研究进展   总被引:4,自引:0,他引:4  
重金属污染土壤的生物修复是一种环境友好型的污染治理技术,是利用生物体将重金属降解、富集、转移而恢复土壤生态功能的过程。综述了植物修复(植物体内降解、植物根系钝化、植物吸收富集、植物气化)、微生物修复、动物修复等技术的研究进展,分析了生物修复技术在实际应用中存在的问题,并展望了研究方向。  相似文献   
48.
49.
The possible response of the carbon (C) balance of China's forests to an increase in atmospheric CO(2) concentration and climate change was investigated through a series of simulations using the Integrated Terrestrial Ecosystem Carbon (InTEC) model, which explicitly represents the effects of climate, CO(2) concentration, and nitrogen deposition on future C sequestration by forests. Two climate change scenarios (CGCM2-A2 and -B2) were used to drive the model. Simulations showed that China's forests were a C sink in the 1990 s, averaging 189 Tg C yr(-1) (about 13% of the global total). This sink peaks around 2020 and then gradually declines to 33.5 Tg C yr(-1) during 2091-2100 without climate and CO(2) changes. Effects of pure climate change of CGCM2-A2 and -B2 without allowing CO(2) effects on C assimilation in plants might reduce the average net primary productivity (NPP) of China's forests by 29% and 18% during 2091-2100, respectively. Total soil C stocks might decrease by 16% and 11% during this period. China's forests might broadly act as C sources during 2091-2100, with values of about 50 g Cm(-2)yr(-1) under the moderate warming of CGCM2-B2 and 50-200 g Cm(-2)yr(-1) under the warmer scenario of CGCM2-A2. An increase in CO(2) might broadly increase future C sequestration of China's forests. However, this CO(2) fertilization effect might decline with time. The CO(2) fertilization effects on NPP by the end of this century are 349.6 and 241.7 Tg C yr(-1) under CGCM2-A2 and -B2 increase scenarios, respectively. These effects increase by 199.1 and 126.6 Tg C yr(-1) in the first 50 years, and thereafter, by 150.5 and 115.1 Tg C yr(-1) in the second 50 years under CGCM2-A2 and -B2 increase scenarios, respectively. Under a CO(2) increase without climate change, the majority of China's forests would be C sinks during 2091-2100, ranging from 0 to 100 g Cm(-2)yr(-1). The positive effect of CO(2) fertilization on NPP and net ecosystem productivity would be exceeded by the negative effect of climate change after 2050. Under the CGCM2-A2 climate scenario and with direct CO(2) effects, China's forests may be a small C source of 7.6 Tg C yr(-1) during 2091-2100. Most forests act as C sources of 0-40 g Cm(-2)yr(-1). Under the CGCM2-B2 climate scenario and with direct CO(2) effects, China's forests might be a small C sink of 10.5 Tg C yr(-1) during 2091-2100, with C sequestration of most forests ranging from 0 to 40 g Cm(-2)yr(-1). Stand age structure plays a more dominant role in determining future C sequestration than CO(2) and climate change. The prediction of future C sequestration of China's forests is very sensitive to the Q(10) value used to estimate maintenance respiration and to soil water availability and less sensitive to N deposition scenario. The results are not yet comprehensive, as no forest disturbance data were available or predicted after 2001. However, the results indicate a range of possible responses of the C balance of China's forests to various scenarios of increase in CO(2) and climate change. These results could be useful for assessing measures to mitigate climate change through reforestation.  相似文献   
50.
The objective of the present study was to develop an immunoassay for multi-determination of the residues of four macrolide antibiotics in milk. Tylosin was derivatized with 6-aminohexanoic acid to synthesize a hapten that was used to produce the monoclonal antibody. The obtained monoclonal antibody simultaneously recognized tylosin, acetylisovaleryltylosin, tilmicosin and desmycosin with crossreactivities of 100%, 91%, 49% and 76%, respectively. Then an indirect competitive immunoassay was developed to determine the four analytes in milk simultaneously. The limits of detection for the four analytes were in the range of 5.5–11.7 ng/mL depending on the compound. The recoveries of the four analytes from fortified blank milk were in the range of 78%–96% with coefficients of variation lower than 11.4%. The developed immunoassay could be used as a practical tool for rapid screening the residues of the four anlytes in milk.  相似文献   
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