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2006年9~10月在长江采集悬浮颗粒物样品,应用改进后的SEDEX法对磷的赋存形态进行了分析.结果表明,自生磷灰石磷是长江悬浮颗粒物中磷的主要赋存形态.涪陵至万州江段,碎屑磷灰石磷的含量较高,弱吸附态磷和有机磷含量较低,磷的赋存形态主要受悬浮颗粒物含量的影响;香溪至葛洲坝下江段,弱吸附态磷和有机磷含量较高,碎屑磷灰石磷含量较低,磷的赋存形态主要受浮游植物生长及泥沙粒径的影响;城陵矶至大通江段,有机磷、碎屑磷灰石磷和铁结合态磷含量较高,弱吸附态磷含量较低,磷的赋存形态主要受泥沙粒径和洞庭湖输入的影响.长江悬浮颗粒物中生物可利用磷占颗粒态磷的45.6%,长江上游水体中生物可利用磷含量较低,下游含量较高. 相似文献
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广州市在以经济高度集中、资源快速利用为标志的城市化过程中,对地下水环境的影响是巨大的,其地下水NH4+和NO2-高浓度区主要集中分布于城市中心区,NO3-超标点除相对集中分布在城市中心区外,在城市外围地带和丘陵区都有分布。造成广州市不同地区的地下水环境三氮污染的原因各不相同,主要为生活和工农业生产等人类活动影响,与河网发育平原区地层沉积特点、地下水形成和赋存条件等自然因素也相关,人类活动对地下水环境的污染途径复杂多样。广州市地下水环境中三氮形态分布受水文地质条件和水文地球化学作用影响明显,主要影响因素有氧化还原环境、包气带岩性、补径排条件、水土环境中的铁锰含量和酸化程度等。 相似文献
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磷污染是水污染的重要组成部分,因其可造成水体富营养化、水质下降,从而引起人们的广泛关注。研究沉积物中不同磷赋存形态及其分布特征有助于了解沉积物中磷的行为特征及迁移能力,从而为水体富营养化防治提供支撑。磷矿的开采、冶炼对矿区内水资源环境可能产生严重影响,本文以安宁磷矿区内河流、水库为研究区域,分析了不同水系沉积物磷元素赋存形态及分布特征,并对其生态风险进行评估。采用X射线荧光光谱法测定研究区水系沉积物总磷(TP)含量,并基于顺序提取及Hupfer改进的磷形态分析方法,将研究区各水系沉积物中磷分为弱吸附态磷(NH4Cl-P)、可还原态磷(BD-P)、金属氧化物结合态磷(NaOH-P)、钙结合态磷(Ca-P)、残渣态磷(Res-P)等5种形态,采用单因子污染指数法对其进行生态风险评估。结果表明：研究区水系沉积物样品中TP含量范围为567.6～48115.5mg/kg,NH4Cl-P含量范围为0.07～115.2mg/kg,BD-P含量范围为8.84～802.5mg/kg,NaOH-P含量范围为21.3～3129.5mg/kg, Ca-P含量范围为12～45098mg/k... 相似文献
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用化学物相分析法测定瓮福磷尾矿中钙、镁、磷元素形态含量。结果表明,磷尾矿中钙主要以白云石的形式赋存,并有少量以方解石、磷酸盐形式存在;镁主要以白云石的形式赋存,并有少量以磷酸盐、硅酸盐形式存在;磷主要以磷灰石的形式赋存,并有少量以铁氧化物、独居石、磷钇矿形式存在。各元素形态加标回收率为97.6%~107.2%,相对标准偏差(RSD,n=12)为0.77%~4.85%。各元素形态分析结果表现出较好的稳定性,表明采用化学物相分析法测定瓮福磷尾矿中钙、镁、磷元素形态含量结果准确可靠。 相似文献
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水体中富营养化水平与磷元素的赋存形态密切相关。目前围绕引起富营养化关键因子之一的磷形态的垂向分布特征、各磷形态间的迁移转化行为及其影响因素取得了比较明确的研究进展。为进一步揭示不同磷形态在沉积物-水体系中迁移转化行为随时空的变化特征,本文采用磷钼蓝分光光度法对沱江流域简阳段间隙水中可溶性活性磷(SRP)、可溶性非活性磷(SUP)及总溶解性磷(TDP)进行测定;采用SMT法和改进的沉积物无机磷形态连续提取法对沉积物中总无机磷(TIP)、总磷(TP)、难提取磷(Res-P)、可交换态磷(Exc-P)、铁结合态磷(Fe-P)、铝结合态磷(Al-P)、钙结合态磷(Ca-P)进行提取,磷钼蓝分光光度法进行测定,以揭示沉积物-水体系中磷的赋存形态垂向分布行为特征,并将实验数据与十年前该地区磷的赋存形态结果进行对比,探讨磷赋存形态的变化趋势及影响因素。结果表明:间隙水中SRP、SUP和TDP的含量分别为0.004～0.36mg/L、0.080～3.19mg/L和0.056～3.28mg/L;沉积物中TP、TIP、Res-P、Exc-P、Al-P、Ca-P含量分别为1235.40～1646.94mg/kg、860.00～1318.59mg/kg、130.31～537.13mg/kg、1.35～14.10mg/kg、0.007～0.12mg/kg、743.13～1109.91mg/kg,Fe-P未检出。对比十年前后沉积物-水体系中磷赋存形态的变化可知,由于受到外源磷输入的影响,间隙水中SRP、SUP以及TDP含量虽然在-10cm以上变化不明显,但在-10cm以下明显增大,且导致沉积物中TP、TIP含量增加;偏碱性的沉积环境导致Al-P的释放,其含量明显减小;Exc-P含量的减小与其转化为稳定的Ca-P或Res-P形态有关。研究认为:随着时空的变化,沱江简阳段沉积物呈现外源磷输入和内源磷释放的综合污染。总体而言,由于输入的磷形态大部分以稳定的Ca-P和Res-P形态存在于沉积物中,使得表层间隙水中生物可直接利用的磷含量总体变化不大,该地区富营养化程度不会加重。维持沉积环境的弱碱性,有利于Al-P、Exc-P等向Ca-P的有效转换,抑制河流富营养化。 相似文献
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沉积物中磷的赋存形态及磷形态顺序提取分析方法 总被引：11，自引：1，他引：10
阐述了当前我国水体富营养化的现状,水体的富营养化与水体中磷、氮的浓度以及二者的浓度比值有着密切的关系。水体富营养化时氮和磷的浓度均很高,但没有一个固定的值,是在一个较宽泛的富营养范围内,氮和磷的浓度比值大多在10∶1～20∶1。湖泊沉积物作为湖泊水体中磷的重要蓄积库,是湖泊流域磷循环的重要归属,也是湖泊水体内源性磷的主要来源,沉积物中极少量的稳定磷转化为活性磷就会造成湖泊水体富营养化。文中介绍了沉积物中无机磷形态的分类,评述了欧盟标准局在研制湖泊沉积物磷形态标准物质时比对采用的4种提取方法(Willimas法、Hieltjes-Lijklema法、Ruttenberg法、Golterman法),总结了国内外学者所应用的沉积物中磷的各种形态提取方法和磷各形态的分析测定方法,国内学者应用的方法是在国外学者方法的基础上提出的,阐述了顺序提取方法及其地球化学意义。简要评述了湖泊沉积物中磷的生物释放、物理释放和化学释放三种释放机制,这三种释放机制相辅相成,在一特定的环境条件下某一过程可能占主导地位来控制沉积物磷的释放。最后提出应该加强对沉积物中磷的各种形态的专属提取剂及其提取有效性的分子表征和检测,更加细化对于沉积物中磷形态的分类和创新各种磷形态的分析方法,建立沉积物-水体磷的迁移、循环和转化模型,这对于从根本上解决富营养化问题具有重要意义。 相似文献
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分级式除磷脱氮工艺探讨 总被引：5，自引：2，他引：3
综合考虑生物除磷与脱氮对环境条件的要求,提出了分级式除磷脱氮的工艺模式,旨在将聚磷菌与硝化菌分别控制在两级反应器中优势生长,以解决硝化菌与其他细菌混合生长系统在除磷与脱氮过程中存在的矛盾关系,达到优化除磷脱氮目的.探讨了分级式除磷脱氮的工艺流程、优化除磷脱氮的可行性及研究要点. 相似文献
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氮是煤中的常见元素之一,煤中氮的赋存形态多样且随煤阶发生变化。以邯郸-峰峰矿区为例,利用X射线光电子能谱（XPS）实验,研究不同变质程度煤（Rran=1.08%~3.67%）中有机氮的赋存形态,探讨煤中各形态有机氮相对含量随煤阶的变化规律。结果表明:按N 1s XPS谱图分峰峰值的结合能可将煤中氮的形态归为N-6、N-5、N-Q和N-X四种;研究区煤中N-5的相对含量最高,且随着煤阶的增高而降低;N-Q的相对含量随着煤阶的增高而增高;煤中N-6的相对含量随煤阶呈“增-减-稳”的变化规律;N-X的相对含量为9.1%~35.1%,其与煤阶关系不明显;在煤阶Rran=1.08%~1.47%的范围内,煤的N 1s XPS谱图中缺失N-Q分峰,表明褐煤中相对含量最高的质子化吡啶氮在此阶段已几乎全部去质子化而转化为吡啶氮。不同变质阶段氮的赋存形态变化特征对燃煤发电及煤化工领域煤化学参数选取提供参考。 相似文献
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J. K. Biswas B. Bera R. Chanda S. K. Sarkar J. Majumdar S. Majumder S. Hazra 《International Journal of Environmental Science and Technology》2018,15(9):1867-1878
Lakes are functionally integral and biologically complex freshwater ecosystems which provide a vast array of ecosystem goods and services to society. Nowadays aquatic ecosystems are being used, misused and abused by diverse anthropogenic activities at an unprecedented rate. The management of lake water quality is usually directed to resolution of conflicts between maintenance of desirable water quality and human-induced degradation of aquatic environment. Nutrients play a decisive role in determining lake’s environmental state through regulation of its primary production. The present study on Saheb Bundh Lake located in Purulia District, West Bengal, India, was undertaken to assess the status of nutrients (nitrogen and phosphorus) subject to certain anthropogenic activities, and to construct models using best subset method which could be adopted as a nutrient management tool. The water samples were monitored for different physicochemical parameters adopting standard methods. It was found that the set of variables including turbidity, temperature, pH, redox potential and total hardness has been championed as the best subset of water quality explaining the dynamics of total phosphorus concentration of freshwater Saheb Bundh Lake. The suite of factors comprising dissolved oxygen, pH, temperature, turbidity and total hardness has been proved as the best subset for estimating total nitrogen concentration. The models developed have been validated for total phosphorus and total nitrogen concentration. For total phosphorus, the model values were found to be very close to the measured values but the values varied widely for total nitrogen, championing the former as a very potent down-to-earth model. 相似文献
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太湖东部湖湾水生植物生长区底泥氮磷污染特征 总被引：6，自引：0，他引：6
为了解太湖东部湖湾(贡湖湾、光福湾、渔洋湾)表层底泥中氮、磷的污染特征及其与水生植物生长的关系,采集了各湖湾滨岸带水生植物生长区的表层底泥,探讨了水生植物的生长与分布对表层底泥中总氮(TN)、总磷(TP)及总有机碳(TOC)等含量的影响,并对表层底泥进行营养评价.结果表明,水生植物生长密集区底泥中TN、TP、TOC的含量均显著低于水生植物零星生长区,说明水生植物的生长对太湖东部湖湾表层底泥中营养盐与有机碳含量具有较为明显的影响;相关性分析显示,表层底泥中TOC与TN含量呈显著相关性(R2=0.832 8),而与TP的相关性则较弱(R2=0.166 5),反映了TOC在湖泊底泥中的沉积可能成为湖泊氮的重要来源,而对磷的影响较小.利用有机指数与有机氮指数两种方法分别对东部各湖湾底泥进行污染评价,贡湖湾、光福湾、渔洋湾底泥有机指数平均值分别为0.142 7、0.228 6与0.208 6,均属较清洁与尚清洁水平,而各湖湾有机氮指数平均值均为Ⅲ与Ⅳ级,说明底泥已遭受了一定程度的氮污染.因此,对水生植物零星生长区表层底泥中氮含量的控制与削减有利于湖泊富营养化的预防与治理. 相似文献
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Márjore Antunes Maísa Trevisan Antunes Andreia Neves Fernandes Janaina da Silva Crespo Marcelo Giovanela 《Environmental Earth Sciences》2013,69(3):959-968
The nutrients, carbon, nitrogen and phosphorus, significantly affect the quality of aquatic environments, especially when present at concentrations above natural levels. In this context, the sedimentary column can act as an environment for storage or accumulation of these nutrients and for the reprocessing of such substances in the water column and aquatic biota. In this context, this study aimed to estimate the concentration of total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), inorganic phosphorus (IP) and organic phosphorus (OP) in seven sediment samples that were collected from the Marrecas Stream microbasin (Caxias do Sul, Rio Grande do Sul State, Brazil). The relationships among the sediment nutrient concentrations and the levels of organic matter (OM), fine material (silt–clay) and the concentration of the metal species, Al, Fe and Mn, as well as the possible nutrient sources to the stream studied were also evaluated. The data set suggest that the TOC and IP appear to have a direct correlation with the vast riparian vegetation present in areas adjacent to the sampling points and to the physico-chemical properties of the water and sedimentary column. Moreover, the results obtained for TN suggest that its concentration possibly suffers interference from the temperature of the water and its oxygenation, in addition to other biological activities. On the other hand, one cannot rule out human interference, mainly in the levels of OP, possibly due to the inflow of domestic sewage to the stream. 相似文献
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Humberto Marotta Luiz Bento Francisco de A. Esteves Alex Enrich-Prast 《Estuaries and Coasts》2009,32(4):654-660
The purpose of this research was to assess the effects of dredging performed in a marginal wetland colonized by aquatic macrophytes
on eutrophication of the adjacent shallow tropical lake (Imboassica Lake, Brazil). The river mouth of the Imboassica River
that drains into Imboassica Lake had been densely colonized by aquatic vegetation dominated by Typha domingensis (Pers.) when it was dredged. Total and dissolved nitrogen and phosphorus concentrations were measured monthly over 13 years
at four stations in the Imboassica river-lake system. Dredging activities reduced phosphorus and nitrogen retention at the
river mouth and subsequently increased these nutrient stocks in the lake waters. Nutrient retention by non-dredged wetland
was estimated to be ca. 1,200 kg year−1 (87.3 g m−2 year−1) for nitrogen and 60 kg year−1 (4.5 g m−2 year−1) for phosphorus. Our whole-lake approach suggested that dredging might intensify rather than mitigate eutrophication in shallow
tropical lakes when the removal of aquatic macrophytes is coupled to the persistence of anthropogenic nutrient inputs from
the watershed. 相似文献
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Effects of climatic changes and anthropogenic activities on lake eutrophication in different ecoregions 总被引：1，自引：0，他引：1
X. Chuai X. Chen L. Yang J. Zeng A. Miao H. Zhao 《International Journal of Environmental Science and Technology》2012,9(3):503-514
Climatic changes and anthropogenic activities could affect nutrients?? status significantly in the different lake ecosystems. Nutrients in Lake Hulun and Lake Taihu, two largest shallow cyanobacteria-blooming lakes in northern and southern China, respectively, were at eutrophicated levels in 2009. The concentrations of total nitrogen and total phosphorus were 3.346 and 2.250?mg/L as well as 0.435 and 0.062?mg/L, respectively, in these two lakes with different causes of eutrophication. For Lake Hulun, it was the decreased amount of water as a result of the warming and drying climate that accounted for the abrupt increase of total nitrogen and total phosphorus levels through inspissation. In addition, the icebound effects, no outflows, low nutrients sequestration by the sediment and the reduction of aquatic productivity made the situation even worse. On the contrary, high population densities, the rapid development of agriculture and industry as well as urbanization have increased the nitrogen and phosphorus loads on Lake Taihu. Therefore, higher criteria of total nitrogen and total phosphorus should be applied in Lake Hulun given the difficulties in controlling climatic changes while much more rigorous standards should be established for Lake Taihu since the anthropogenic impacts on nutrient status are relatively easy to control. 相似文献
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矿物-腐殖质间的交互作用是土壤和水体沉积物及悬浮颗粒物中环境物质的重要界面过程。不管是氮、磷植物性营养元素还是有毒的重金属、有机物，它们在表生环境中的迁移转化与归趋受到矿物、腐殖质及其复合体的表面活性和迁移性的调控。矿物-腐殖质体系的界面作用研究是前沿性的研究领域，主要目的是揭示矿物-腐殖质复合体的结构特性(例如颗粒物的圈层结构与表面微形貌)及其与颗粒物表面活性的关系，进而揭示土壤和水体环境中矿物-腐殖质间的交互作用规律。本文对该领域的研究现状进行评述，并提出未来可能的发展趋势。 相似文献
17.
Eutrophication-induced changes to benthic faunal activities are problems of significant ecological impact, affecting global
nutrient budgets as well as local trophic connections. We address the question of how nitrogen loads to estuarine embayments
alter the bioturbation activities of benthic fauna. Specifically, we related local benthic activities to calculated local
nitrogen concentrations for 22 northeastern US estuaries. These local nitrogen concentrations were derived from the calculated
nitrogen loading for the embayment together with the spatial distribution of the local flushing time. Our results showed a
maximum bioturbation rate at intermediate nitrogen concentrations or a “hump-shaped” pattern of response. This behavior was
evident in all embayments that had a range of concentrations including low, intermediate, and high values. Embayments where
sampling did not include this full range did not show this behavior. This work provides methods and guidance to help managers
make decisions concerning the effects of nitrogen loading on the activities and well-being of benthic fauna in coastal embayments.
The novelty of this approach lies in identifying the response of bioturbation to nitrogen loading in many systems, without
costly and time-consuming speciation of benthic fauna, and also in rapidly identifying embayments and aquatic areas with vulnerable
fauna. These results are ecologically significant in supporting the hypothesis that benthic organism abundance and activity
will peak at mid-levels of nitrogen due to the interplay of food availability and oxygen levels, noting that the critical
levels of these factors differ among water bodies. 相似文献
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天津临港经济区地处滨海, 完全是由填海造陆形成的人工陆地。土壤是港口航道清淤淤泥、近海海沙吹填围海造陆后形成的吹填土, 其性质特殊, 研究吹填土壤中氮磷空间分布对了解该区域环境状况有重要意义。研究发现:天津临港吹填土整体含氮量较低, 按土层深度分布, 平均质量分数为161.73~240.09 mg/kg;含磷量相对丰富, 平均质量分数为355.54~443.27 mg/kg;总氮变异系数较大, 总磷变异系数较小, 氮、磷质量分数主要受不同区域吹填土性质影响。吹填土中有机磷质量分数较少, 平均仅占总磷的3.83%, 吹填土中磷大多以无机磷形式存在, 其相对质量分数从大到小为:钙结合磷(Ca-P) >铁结合磷(Fe-P) >铝结合磷(Al-P) >闭蓄态磷(Oc-P) >碎屑磷(De-P) >交换态磷(Ex-P)。研究表明, 临港吹填土氮、磷质量分数水平对近海环境有潜在富营养污染威胁。 相似文献