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随着人们生活水平的日益提高,对生活饮用水水质要求也逐步提高,本文就浏园水厂锰含量季节性超标问题进行了分析和处理,以满足生活、生产的要求。 相似文献
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随着人们生活水平的日益提高,对生活饮用水水质要求也逐步提高,本文就浏园水厂锰含量季节性超标问题进行了分析和处理,以满足人们日常生活生产的需要。 相似文献
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生态城市的提出为城市的发展找到了一种理想模式,成为现代城市发展建设的方向和目标。生态城市理论研究主要应用在城市的规划、设计和管理上。生态城市建设的评价是衡量生态城市规划、建设、管理成效的主要依据。本文以佳木斯市为研究对象,构建了包括4个层次3个子系统10个分目标30个具体指标的佳木斯市生态城市建设综合评价指标体系,对佳木斯市2004年至2008年5年间的生态城市建设进行综合评价。根据评价结果来指导佳木斯市生态城市建设。进而实现佳木斯市经济可持续发展和生态环境不断优化"双赢"目标的城市可持续发展道路。 相似文献
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目前,噪声污染作为城市的四大公害之一,随着城市规模、交通运输和娱乐业的发展,噪声污染的信访案件也在不断的增加。近几年,佳木斯市的噪声污染问题也在不断突显,以佳木斯市“十一五”期间的噪声监测数据为基础,介绍了城市声环境质量状况,并通过对道路交通、社会生活等声环境监测结果来反映道路交通、社会生活等声环境质量的变化趋势、声环境污染特征及声质量变化趋势等问题进行分析,并提出了佳木斯市噪声污染防治的意见及建议。 相似文献
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The dynamics of Cd scavenging from solutions by Fe/Mn oxides in natural surface coatings (NSCs) was investigated under laboratory conditions. Selective extraction methods were employed to estimate the contributions of Fe/Mn oxides, where hydroxylamine hydrochloride (0.01 mol/L NH2OH-HCl + 0.01 mol/L HNO3), sodium dithionite (0.4 mol/L Na2S2O4) and nitric acid (10% HNO3) were used as extraction reagents. The Cd scavenging was accomplished with developing periods of the NSCs (totally 21 data sets). The resulting process dynamics fitted well to the Elovich equation, demonstrating that the amount of Cd scavenged was proportional to the increments of Fe/Mn oxides that were accumulated in the NSCs. The amount of Cd bound to Fe oxides (MCdFe) and Mn oxides (MCdMn) could be quantified by solving two equations based on the properties of two extraction reagents. The amount of Cd scavenged by Fe/Mn oxides could also be estimated using MCdFe and MCdMn divided by the total amounts of Fe and Mn oxides in the NSCs, respectively. The results indicated that the Cd scavenging by Fe/Mn oxides was dominated by Fe oxides, with less roles attributed to Mn oxides. The estimated levels of Cd scavenging through Fe and Mn oxides agreed well with those predicted through additive-adsorption and linear-regression models. 相似文献
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IntroductionArhaReservoirislocatedintheplateauregionofSouthwestChina.Thisreservoir,withavolumeof445millionm3,wasbuiltin1960andisth?.. 相似文献
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泉州湾红树植物中重金属元素的分布与储量 总被引:1,自引:0,他引:1
用ICP-AES测定了泉州湾洛阳江河口红树植物桐花树(Aegiceras corniculatum)和秋茄(Kandelia candel)根际沉积物中重金属总量和有效态含量,以及这2种植物体内重金属的含量,探讨了该红树林湿地重金属元素的分布、富集和储量情况。结果表明,2种红树植物根际沉积物中重金属总量均表现为:Fe>Mn>Zn>V>Pb>Cr>Cu>Ni>Co>Cd,有效态含量均表现为:Fe>Mn>Zn>Pb>Cu>V>Cr>Ni>Co>Cd,部分重金属具有一定潜在的有害生物效应;Fe、V在2种红树植物根部的含量最高,Mn在叶中的含量最高,其余重金属未有明显的统一规律;相关性分析表明,2种植物根中Cu和Zn,Pb和V、Co、Ni,Cr和Zn,Zn和V,V和Co、Ni,Co和Ni之间互有明显协同作用;除Mn在叶中存在较强的富集能力(富集系数大于1),2种红树植物对其余重金属元素的富集能力均较小,远达不到超富集植物的要求;秋茄和桐花树对Mn从根向叶的迁移能力最强,Cu、Cr、Zn在2种植物中的迁移系数均大于1,Cd在桐花树中的迁移系数也大于1,说明2种植物都有将这些元素向叶中输送的趋势,应注意其通过食物链富集作用引起的危害。2种红树植物中重金属总储量大小表现为:Mn>Fe(秋茄则Fe>Mn)>Zn>Cu>Cr>Pb>V>Ni>Co>Cd,其中Mn和Fe的总储量之和分别占到了总储量的97.7%(桐花树)和99%(秋茄)。 相似文献
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温榆河水体中重金属含量分布及赋存状态解析 总被引:6,自引:2,他引:4
利用错流超滤技术对采集的温榆河水样中Fe、Mn、Al、Zn、Cu、Cr和Pb等金属元素进行了分离,研究温榆河重金属分布及赋存状态变化.研究发现,温榆河沿程重金属含量多数超出了《地表水环境质量标准》(GB3838—2002)的Ⅰ类水标准,Pb超过了Ⅱ类水标准;其中Fe、Al、Cu、Pb等元素主要以颗粒态存在,Mn、Zn则主要以溶解态存在,而Cr在颗粒态和溶解态中含量相当.温榆河沿程各点金属元素在胶体态和真溶解态中均有分布,Mn、Al、Zn、Pb等元素以真溶解态存在量较多,而Fe、Cr、Cu等元素则以胶体态存在量较多,其中,河流中的Cu元素分布状态受外界影响严重,Cr和Mn的分布状态不易受外界因素影响,Fe的分布状态易受总含量的影响,Al和Zn的分布状态易受pH值的影响,Pb的分布状态易受河流富氧状态的影响.通过胶体态重金属与胶体态有机碳的相关性分析发现,温榆河中胶体态Fe、Mn、Zn及Al主要以无机胶体态存在;而胶体态Cu、Cr和Pb则主要以有机胶体态存在. 相似文献
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南沙群岛海域沉积物环境与间隙水中的铁锰 总被引:10,自引:0,他引:10
研究了南沙群岛海域泻湖及礁外沉积物间隙水中的Fe^2+、Mn^2+、浓度及其比值、沉积物-海水界面扩散通量、沉积物类型及其氧化还原环境。结果表明,间隙水中的Fe^2+、Mn^2+浓度泻湖高于礁外,Fe^2+(礁)/Fe^2+(泻)浓度比为0.28,Mn^2+(礁)/Mn^2+(泻)浓度比为0.66,Mn^2+/Fe^2+比值泻湖内为1.47,礁外为3.52,Fe^2+、Mn^2+均是从沉积物向上覆 相似文献
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TheeffectoflightontheMn(II)orFetlll)xatalyzedoxidationofaqueousS(IV)XuYongfu(InstituteofAtmosphericPhysics,ChineseAcademyofSc... 相似文献
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Investigation on Fe, Mn, Zn, Cu, Pb and Cd fractions in the natural surface coating samples and surficial sediments in the Songhua River, China 总被引:3,自引:0,他引:3
Natural surface coating samples (NSCSs) from the surface of shingles and surficial sediments (SSs) in the Songhua River, China were employed to investigate the relationship between NSCSs and SSs in fractions of heavy metals (Fe, Mn, Zn, Cu, Pb, and Cd) using the modified sequential extraction procedure (MSEP). The results show that the differences between NSCSs and SSs in Fe fi'actions were insignificant and Fe was dominantly present as residual phase (76.22% for NSCSs and 80.88% for SSs) and Fe-oxides phase (20.33% for NSCSs and 16.15% for SSs). Significant variation of Mn distribution patterns between NSCSs and SSs was observed with Mn in NSCSs mainly present in Mn-oxides phase (48.27%) and that in SSs present as residual phase (45.44%). Zn, Cu, Pb and Cd were found dominantly in residual fractions (〉48%), and next in solid oxides/hydroxides for Zn, Pb and Cd and in easily oxidizable solids/compounds form for Cu, respectively. The heavy metal distribution patterns implied that Fe/Mn oxides both in NSCSs and SSs were more important sinks for binding and adsorption of Zn, Pb and Cd than organic matter (OM), and inversely, higher affinity of Cu to OM than Fe/Mn oxides in NSCSs and SSs was obtained. Meanwhile, it was found that the distributions of heavy metals in NSCSs and SSs were similar to each other and the pseudo-total concentrations of Zn, Cu, Pb and Cd in NSCSs were greater than those in SSs, highlighting the more importance for NSCSs than SSs in controlling behaviours of heavy metals in aquatic environments. 相似文献
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长期不同耕作方式对紫色水稻土重金属含量及有效性的影响 总被引:14,自引:5,他引:9
通过长期定位试验,研究了常规平作、水旱轮作、免耕冬水、垄作免耕和厢作免耕5种耕作方式对紫色水稻土剖面重金属(Fe、Mn、Cu、Zn、Pb、Cd)总量、有效量及水稻根、茎叶和糙米重金属含量的影响.结果表明,经过22 a的耕作,5种耕作方式对紫色水稻土剖面Fe、Cu、Zn、Pb、Cd总量的剖面分布状况影响不显著,而对土壤Mn的剖面分布状况影响显著,常规平作、水旱轮作及免耕冬水均导致表层土壤Mn向下层淋失.5种耕作方式下土壤Fe、Cu、Zn、Pb和Cd的有效量均随土层深度的增加呈降低趋势,而常规平作、免耕冬水、垄作免耕及厢作免耕土壤Mn有效量则表现出随土层深度的增加而增高的趋势.5种耕作方式下,表层土壤Fe、Mn有效量以水旱轮作最高,Zn、Pb有效量以常规平作最高,而Cu有效量受耕作方式的影响不显著.相关分析结果表明,表层土壤有效Fe与pH呈极显著的负相关关系,与有机质呈显著的负相关关系,有效Mn与pH和有机质均呈极显著的负相关关系,有效Zn与总Zn呈显著正相关关系.水旱轮作、垄作免耕及厢作免耕条件下水稻根部Fe、Mn含量,茎叶Fe、Mn、Cu、Cd含量,糙米Cu含量均高于常规平作和免耕冬水,水旱轮作能明显降低Cd向糙米的迁移系数,对降低糙米Cd含量有明显的效果,且水旱轮作条件下糙米Cd含量低于国家食品卫生标准.水稻根部Fe含量与pH呈极显著负相关关系,与有效Fe呈极显著正相关关系,根部Mn含量与pH呈极显著负相关关系,与有效Mn呈极显著正相关关系,茎叶中Mn含量与pH呈显著的负相关关系,与总Mn及有效Mn呈显著的正相关关系,茎叶和糙米Cu含量与pH均呈极显著的负相关关系,糙米中Zn含量与pH呈显著负相关关系,与CEC呈极显著正相关关系.结果表明,耕作方式主要通过影响土壤pH而影响土壤重金属的有效量及水稻重金属的含量,水旱轮作可提高表层土壤Fe、Mn活性,降低土壤Zn、Pb和Cd活性,并能在一定程度上降低糙米Pb、Cd含量,但也应注意长期的水旱轮作可能会导致表层土壤Mn过度向下层淋溶. 相似文献