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351.
针对磷和微量元素对藻类生长的共同作用,研究不同磷源条件下锌对藻细胞生长与产毒的影响。实验选用铜绿微囊藻为藻种,分别以无机磷磷酸氢二钾(K_2HPO_4)、小分子有机磷甘油磷酸钠(NaGly)和大分子有机磷卵磷脂(LEC)为磷源,研究不同锌(Zn~(2+))含量对藻细胞的藻密度、碱性磷酸酶活性(alkaline phosphatase activity,APA)以及胞内藻毒素(MC-LR)的影响。研究发现:以NaGly为磷源时微量元素锌对藻细胞生长的促进效果显著,而以K_2HPO_4或LEC为磷源时,锌含量的变化对藻细胞生长无显著影响。APA不仅与磷源有关而且与锌含量相关,以LEC为磷源时的APA显著高于以K_2HPO_4或NaGly为磷源时的APA,且锌含量越低APA越低,以K_2HPO_4为磷源时锌含量越低APA越高,而锌对以NaGly为磷源时的APA几乎没有影响。磷源与微量元素锌对藻细胞的产毒均产生影响,NaGly有利于藻毒素的产生; LEC不利于藻细胞的产毒,但锌含量越低藻细胞的产毒量越多。综上所述,磷源与微量元素锌共同作用对藻细胞的生长与产毒产生影响,小分子有机磷NaGly与锌的效果显著。 相似文献
352.
为探究室内地面灰尘中15种多环芳烃(PAHs)污染的时间变化规律,于2012年3—7月对北京市一座办公楼内的某办公室进行了每周一次的连续高密度灰尘样品采集。利用高效液相色谱-荧光检测器检测15种PAHs含量。结果表明,该办公室内灰尘样品中∑PAHs浓度范围为1 180~24 300 ng·g~(-1),平均浓度为8 960 ng·g~(-1)。总体上,检出的PAHs以3环PAHs为主,其中菲占PAHs总量的59%以上,其次是4环和5环PAHs,4环PAHs中占的比重最高,约占4环PAHs总量的34%。该办公室内灰尘中∑PAHs的浓度存在显著的时间变化差异,总体表现为∑PAHs浓度随气温升高而降低的趋势。源解析结果显示,机动车排放源、石油源、木材与煤燃烧是北京市室内灰尘中PAHs的主要来源。健康风险评估结果显示,ILCR皮肤接触ILCR手口摄入,且CR均值大于10-6,说明该采样点的PAHs污染存在"潜在致癌风险"。 相似文献
353.
354.
中国矿山环境治理恢复保证金制度 总被引:2,自引:0,他引:2
由于中国当前的矿山环境保护政策尚不能从根本上解决矿山环境的主要问题,作为责任主体的矿山企业不能积极主动实施矿山环境治理与恢复。矿山环境治理恢复保证金是为了保证采矿权人履行矿山环境治理恢复义务而缴纳的资金。建立矿山环境治理恢复保证金制度就是为了贯彻"谁污染、谁治理;谁破坏,谁恢复"的环保原则,促进采矿权人在采矿过程中保护矿山环境,并确保在闭坑、停办、关闭后受破坏的矿山生态环境得到治理恢复的一项特别的经济手段和措施。实施保证金制度可以更好地促进矿产资源开发的外部成本内部化,是矿山环境保护必要且有效的形式。 相似文献
355.
综述了厌氧处理工艺应用于工业废水处理的研究进展,并对厌氧工艺与好氧工艺进行了对比,总结了厌氧工艺的特性;阐释了厌氧工艺的应用现状及未来的发展趋势,重点介绍了厌氧流化床反应器(AFBR)、上流式厌氧滤池、上流式厌氧污泥床反应器(UASB)、厌氧折流板反应器(ABR)、颗粒污泥膨胀床反应器(EGSB)、复合厌氧反应器。 相似文献
356.
Polycyclic aromatic hydrocarbons and organochlorine pesticides in surface soils from the Qinghai-Tibetan plateau 总被引:4,自引:0,他引:4
Tao S Wang W Liu W Zuo Q Wang X Wang R Wang B Shen G Yang Y He JS 《Journal of environmental monitoring : JEM》2011,13(1):175-181
Eighty eight surface soil samples were collected from the Qinghai-Tibetan Plateau (QTP) for determination of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane and metabolites (DDXs) and hexachlorocyclohexane isomers (HCHs). The measured concentrations were 51.8 ± 38.5 ng g(-1), 0.329 ± 0.818 ng g(-1), and 0.467 ± 0.741 ng g(-1) as means and standard deviations of PAHs, DDXs, and HCHs, respectively, which were 1-2 orders of magnitude lower than those reported for eastern China. Significant differences were also revealed among four sub-areas within QTP. PAHs detected in the samples from the remote sub-areas of T'ang-ku-la/Hoh Xil Mountains and along the Qinghai-Tibet highway in the west and northwest of QTP were 1 order of magnitude lower than those from Lhasa and east Qinghai. The differences in soil OCPs among the sub-areas were 2-7 times. Soil PAHs were significantly correlated with emission density and soil organic carbon content (SOC), while OCPs were correlated significantly with the population density and SOC. Based on the calculated backward air mass trajectories and geographical distributions of emission and population, it was revealed that PAHs and OCPs accumulated in the soils in the west and northwest QTP were primarily from long-range transport and may represent the background levels of East Asia. This part of QTP can also serve as an important receptor area for regional or even global long-range transport study. The elevated concentrations of PAHs and OCPs in Lhasa and east Qinghai were mainly from local sources, while PAHs from adjacent Lanzhou area also contributed considerably to the accumulation of PAHs in east Qinghai. 相似文献
357.
哈尔滨市城市内涝监测预警系统建设 总被引:2,自引:0,他引:2
简要介绍了哈尔滨市城市内涝监测预警系统的主要组成部分、核心技术及理论基础、重要应用价值及意义,并通过在一次强降水实例中的检验,证明该系统具有较高的精确度.在系统核心环节--积水仿真模型的建立中,该项目突破了传统规则网格的划分法,而是根据城市地形地貌特点独创了无结构不规则网格技术.此外,仿真模型中对排水工程设施进行了数字概化,首次实现了地面积水与管道水体模拟之间的结合;初步解决了哈尔滨特有的陆地泵排水模拟问题;将监测雨量信息和数值天气预报信息带入仿真模型,实现了气象学与水文学的结合.通过运行该系统,可以提高对积水预报的准确度. 相似文献
358.
海河干流、大沽排污河沉积物中有机氯农药的残留状况 总被引:7,自引:0,他引:7
调查了海河干流和大沽排污河沉积物中持久性有机氯杀虫剂(OCPs)的残留状况.在所选取的16个断面沉积物样品中均有大量HCHs、DDTs检出,表明海河和大沽排污河的DDT和HCH污染相当严重.海河沉积物中HCHs和DDTs总质量浓度分别为3.30~75.96、1.57~221.57 ng/g.大沽排污河沉积物中HCHs和DDTs的残留量分别为2.30~124.61、11.28~237.30ng/g.与国内外部分河流表层沉积物中HCHs、DDTs的含量相比,海河和大沽排污河沉积物中有机氯农药含量较高.最后根据两条河流沉积物中的OCPs的残留量,分析了其可能的污染源. 相似文献
359.
Spatio-temporal variations of nitrogen in an agricultural watershed in eastern China: catchment export, stream attenuation and discharge 总被引:3,自引:0,他引:3
Chen D Lu J Shen Y Gong D Deng O 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2989-2995
Using the monthly hydrogeochemical data of ChangLe River system from 2004 to 2008, total nitrogen (TN) export load (S(n)) from nonpoint sources (NPS) to stream and in-stream attenuation load (A(L)) was estimated by the inverse and forward format of an existing in-stream nutrient transport equation, respectively. Estimated S(n) contributed 96 ± 2% of TN entering the river system, while A(L) reduced the input TN by 23 ± 14% in average. In-stream TN attenuation efficiency in high flow periods (10 ± 5% in average for the entire river system) was much lower than that in low flow periods (39 ± 17%). TN attenuation efficiency in tributaries (28 ± 16% in average) was much higher than that in mainstream (11 ± 8%). Hydrological conditions are important in determining the spatio-temporal distributions of NPS TN export, stream attenuation and discharge. Increasing the water residence time might be a practical method for mitigating stream TN. 相似文献
360.
The effects of chemical amendments (calcium carbonate (CC), steel sludge (SS) and furnace slag (FS)) on the growth and uptake of cadmium (Cd) by wetland rice, Chinese cabbage and wheat grown in a red soil contaminated with Cd were investigated using a pot experiment. The phytoremediation of heavy metal contaminated soil with vetiver grass was also studied in a field plot experiment. Results showed that treatments with CC, SS and FS decreased Cd uptake by wetland rice, Chinese cabbage and wheat by 23-95% compared with the unamended control. Among the three amendments, FS was the most efficient at suppressing Cd uptake by the plants, probably due to its higher content of available silicon (Si). The concentrations of zinc (Zn), lead (Pb) and Cd in the shoots of vetiver grass were 42-67%, 500-1200% and 120-260% higher in contaminated plots than in control, respectively. Cadmium accumulation by vetiver shoots was 218 g Cd/ha at a soil Cd concentration of 0.33 mg Cd/kg. It is suggested that heavy metal-contaminated soil could be remediated with a combination of chemical treatments and plants. 相似文献