水源型水库底泥中磷形态及其分布特征研究

以长江下游某水源型水库为例,对水库表层底泥应用淡水沉积物磷形态的标准测试程序（SMT）测定了总磷（TP）、铁铝结合态磷（Fe/Al-P）、钙结合态磷（Ca-P）、无机磷（IP）和有机磷（OP）,分析了各形态磷之间的相关性。研究结果表明：水库总磷含量在652.55～889.78 mg/kg ,表层沉积物中 T P含量的增加主要来自Fe/Al-P部分,其次来自IP和OP部分。OP含量与 Ca-P和 Fe/Al-P的含量均有较好的正相关关系,而Ca-P 与 Fe/Al-P相关性较弱。5个采样点底泥中的铁铝结合态磷含量都低于钙结合态磷,且两者比值都小于0.5,应考虑环境酸化引起的磷释放风险。     

广州城市河涌氮、磷污染研究

对广州市区典型河涌氮、磷污染进行分析研究。结果表明:上覆水中氨氮质量浓度为6.21~22.40 mg/L,间隙水中氨氮质量浓度为19.9~152.0 mg/L。河涌上覆水以及间隙水中的氮污染主要是无机氮污染,且以氨氮为主,占总无机氮的90%以上。各河涌的氨氮和总氮值之间表现出很强相关性,但上覆水的氨氮和总氮值与间隙水的氨氮和总氮值之间,却不存在明显相关性。底泥间隙水与上覆水磷形态差异较大,间隙水中可溶性正磷酸盐与总磷具有较好的相关性,且有机磷质量浓度比上覆水要高;底泥中可溶性磷(Psol)、铝结合磷(PAl)质量浓度较低,铁结合磷(PFe)质量浓度较高。悬浮物中各形态磷质量浓度整体上均比底泥样品要高。     

抚仙湖水体磷的时空分布特征分析

抚仙湖是中国第二大深水湖，保护好抚仙湖水质对于中国水资源战略安全至关重要。总磷是影响贫营养深水湖泊水质类别的关键因素。通过在抚仙湖湖体均匀布设立体监测点位，开展为期1 a的水质监测分析，探讨不同形态磷的水平和垂向分布及季节变化特征。结果表明：(1)抚仙湖总磷(TP)、溶解性总磷(DTP)及溶解性磷酸盐(SP)随水深几乎呈线性增加趋势；溶解性有机磷(DOP)除个别点随水深波动外，整体较为稳定；总体上，底层水体磷浓度高于表层水体磷浓度，表层底泥总磷浓度高达1 926 mg/kg,可能对未来湖泊的富营养化构成风险。(2)不同形态磷浓度TP>DTP>SP>DOP,其中DTP占TP的比例为77.78%,为TP的主要贮存方式。(3) TP浓度总体是上半年高于下半年，呈现一定的冬春季表层浓度升高、底层浓度降低的趋势，该趋势与温跃层消退、湖水处于混合状态有关。研究成果可为抚仙湖水质趋势研判和精准治理工作提供支撑。     

间歇性波浪扰动下河口底泥中磷释放特性研究

作为反映河流、海洋水体受污历史的载体,河口底泥在污染达到一定程度时易在海洋动力作用下释放沉积其中的污染物,影响水体水质。为了明确秦皇岛近岸海域内污源染,量化波浪扰动下底泥释放对水质的影响,该研究以波流水槽为动力试验设备,选取秦皇岛污染最严重的河流之一大蒲河的河口底泥为研究对象,试验研究河口底泥在间歇性波浪扰动下磷的释放特性。总磷在波浪扰动下的释放可分为浓度迅速增加的初期和浓度随时间线性增加的稳定期两个阶段,浓度随波高增大而升高,且在波高大于8 cm时与浊度呈显著正相关。溶解性总磷受浓度梯度和波浪引起的孔隙水压力影响向上覆水体迁移扩散,随时间呈小幅增加。总磷在波浪扰动初期的释放强度为2.00×10~(-3)–8.75×10~(-3) mg/m2/s,是稳定期释放强度0.50×10-4–2.25×10~(-4) mg/m~2/s的18–40倍,且两个阶段的释放强度均随波高呈指数增长。当波浪强至起动底泥,原先的泥水界面释放转为底泥起动悬浮释放,水体中颗粒态磷取代溶解态磷成为磷的主要赋存形态。间歇性波浪扰动静置期,颗粒态磷的吸附沉降使得水体中总磷浓度和颗粒态磷的比例大幅降低。     

沉水植物苦草对上覆水各形态磷浓度的影响

沉水植物是影响湖泊磷营养状态的重要因素。在室内模拟了"水-苦草-沉积物"生态系统,在沉水植物苦草生长过程中分析上覆水中的总磷(TP)、溶解性总磷(TDP)、溶解性有机磷(DOP)、溶解性活性磷(SRP)、颗粒态总磷(PP)的变化,探讨了苦草对上覆水磷赋存形态的影响。结果表明,苦草在生长过程中减缓了沉积物磷的相对释放速率使上覆水中TP、SRP、DOP、PP均呈现不同程度的下降。上覆水TP、SRP、DOP、PP分别下降了37.5%、74.6%、42.0%、19.5%;苦草主要通过吸收上覆水和间隙水中的磷及对环境因子的影响,使得上覆水中各形态磷浓度保持在较低的水平,降低沉积物向水体释放磷的速率。     

底泥疏浚对湖泊内源磷释放的短期效应研究

对大纵湖底泥疏浚的短期效应进行模拟实验,分析了上覆水体的Eh、pH和磷质量浓度随时间的变化规律,以及沉积物中总磷、无机磷、有机磷、铁/铝磷、钙磷等5种形态磷质量比的垂向变化规律。结果表明:底泥疏浚30 cm对上覆水体Eh、pH以及磷浓度控制效果不显著,且沉积物磷形态不是影响沉积物释磷的主要因素。     

太湖总磷升高的原因分析

根据太湖水量、水质、底泥和蓝藻监测资料，从外源总磷（TP）输入和内源磷循环2个角度，系统分析太湖水量、水质、底泥、蓝藻等要素与湖体TP质量浓度的关系，揭示了影响太湖TP升高的主要因素，为新一轮太湖水环境综合治理提供技术支撑。     

玄武湖沉积物磷形态的垂向变化和生物有效性

采用不同的化学提取法,分析玄武湖西北湖区沉积物中各形态磷、生物可利用磷(BAP)的垂向变化,探讨了各层沉积物中磷的生物有效性。结果表明,沉积物中总磷以无机磷为主,BAP占总磷的20%~52.6%,玄武湖底泥的磷有较好的生物可利用性。不同地点沉积物各磷形态和BAP的垂向变化有较大的差异。1号采样点的总磷、无机磷、铁磷和BAP质量比在沉积0~20 cm处较高,20~40 cm逐渐减小,说明0~20 cm内释磷潜力较大;2号采样点的总磷和无机磷质量比先减小,20~40 cm逐渐增加,而BAP和铁磷质量比随深度增加呈上升趋势,说明2点深层具有较大的释磷潜力。铁磷与BAP相关性较好,这部分磷具有较大的潜在释放风险。     

淮河淮南段底泥氮磷垂直分布研究

对淮河淮南段国家控制断面柱状样底泥的岩性、理化性质及氮磷形态的垂直分布特征进行了研究.结果表明,0～20 cm内底泥的含水率与有机质含量间有显著的正相关性(r=0.963).不同断面氮的含量及形态分布差异较大,一般都在20 cm处发生明显的转折,TN、NH+-4-N、NO--3-N含量的最高值均出现在姚家湾;NH+-4-N、NO--3-N含量总和占TN的比例极小,有机氮及地质氮可能是淮河底泥氮的主要存在形式;底泥磷的形态分布特征相似,钙磷(Ca-P)含量在各层所占的比例约占该层TP的40%;闭蓄磷(O-P)在峡山口、石头埠、湖大涧3个断面所占的比例仅次于Ca-P;铁磷(Fe-P)在姚家湾、石头埠相对较高.最具释放潜力的水溶性磷、Al-P、Fe-P在4个柱状样底泥中都较低;三者之和约占TP的20%左右.研究结论为:淮河淮南段底泥磷的释放不会对淮河的富营养化起太大的作用,外源输入和底泥氮的释放是淮河水体富营养化的主要原因.     

洋河水库底泥磷的释放规律研究

本文研究了洋河水库底泥中磷的释放规律。通过调整上覆水的DO、pH、温度等条件，在室内进行静态模拟试验，得到了如下结果：厌氧条件促进底泥无机磷的释放，好氧条件抑制底泥磷的释放，同时还可吸收水体中的磷；弱酸性或弱碱性上覆水条件均促进底泥中磷的释放；随着温度的升高，底泥中无机磷的释放量也随之增加。     

瓦埠湖沉积物中氮与磷赋存形态分析

利用连续提取法研究了瓦埠湖沉积物中磷的赋存形态和氮的组成特征。结果显示:瓦埠湖沉积物中总磷含量为293～874 mg/kg,平均为470 mg/kg,总磷主要由无机磷组成;在沉积物的提取磷中铁结合态磷为主要赋存形态;铁磷、钙磷、铝磷的相对百分含量指示出该湖泊的磷源自污染较少的区域。瓦埠湖沉积物中总氮的含量为208～464 mg/kg,平均为265 mg/kg,氮的主要组成为有机氮,有机氮、有机指数等显示该湖泊属于清洁类型,未遭受污染。瓦埠湖流域的社会与自然状况的调查结果、湖泊底泥的有机碳氮比等均表明湖泊营养物质来自面源,各指标含量在空间分布的特点与相关性的差异,说明了物质沉积存在重力分离与水动力作用的过程。     

洋澜湖沉积物中磷的分布及污染评价

我国城市湖泊的生态系统功能下降,城市湖泊富营养化问题也日趋严重。城市湖泊的富营养化通常表现为磷限制,而湖泊沉积物是磷的主要归宿地。研究沉积物中磷的含量及分布特征,对探明其污染状况及湖泊富营养化的控制与治理具有重要的参考意义。洋澜湖作为典型的城市湖泊,近年来存在富营养化问题,以洋澜湖作为研究对象,分析其表层沉积物中的总磷(TP)浓度及空间分布特征,采用单因子指数法对沉积物中磷的污染情况进行评价,并选取3个代表性区域分析沉积物中磷的形态及垂向分布。结果表明,洋澜湖表层沉积物中TP的浓度为528~3 568 mg/kg,平均值1 096 mg/kg,其中西湖湖区的TP浓度最高,平均值1 362 mg/kg;洋澜湖表层沉积物总磷污染评价指数为0.88~5.95,表明整个湖区的沉积物均呈现一定程度的磷污染,其中轻度污染区域所占比例为9.38%,中度污染区域所占比例为32.81%,重度污染区域所占比例为57.81%。通过对沉积物中磷形态进行分析,沉积物中可交换态磷所占比例较小,铁铝结合态磷所占比例最高,是洋澜湖沉积物中磷释放的主要来源。     

洪湖沉积物碳氮磷分布特征及污染评价

洪湖是中国第七大淡水湖,富营养化问题日益突出。全面了解洪湖沉积物氮、磷、有机质的含量及分布特征,对掌握其富营养化现状与氮磷污染生态风险具有重要意义。在湖区布设了8个采样点,2019年10月采集50 cm柱状沉积物,分别测定不同深度沉积物总氮(TN)、总磷(TP)以及有机质(OM)含量,分析了TN、TP 和OM 含量的空间分布特征及相关性,并运用综合污染指数法评价其对应的污染程度。结果表明:洪湖沉积物TN含量在467.8~8 454.5 mg/kg之间,平均值2 167 mg/kg,为重度污染,其中近一半的采样点表层沉积物TN含量>5 000 mg/kg;TP含量在502.7~1 252.4 mg/kg之间,平均值693.8 mg/kg,除杨柴湖为重度污染外,其他大部分地区为中度污染;有机质含量占比在5.0%~24.9%之间,平均值9.6%,为重度污染。在垂直空间上,TN、TP 和OM 均在沉积物表层垂向深度0~20 cm存在明显的积累,其含量随垂向深度的增加而迅速降低。研究成果可为洪湖富营养化的控制与治理提供科学数据支撑。     

Sediment phosphorus characteristics in the clearwater state of Lake Mogan, Turkey

This study examined the vertical distributions of total phosphorus (TP) and phosphorus fractions, and the iron and organic matter, in the littoral sediment in a macrophyte‐dominated, clearwater state in Lake Mogan between September 2005 and August 2006. Benthic macroinvertebrates and total bacteria in the sediment also were determined. No clear seasonal or depth‐related (0–20 cm) patterns were found in sediment concentrations for the measured parameters. The phosphorus release was quantitatively very low, and a negative phosphorus release (–0.132 µg m^?2 day^?1) was measured during the summer months. The TP concentrations of the sediment samples ranged between 675.00 and 1463.80 µg g^?1 dry weight (DW), and the trophic level of the lake was eutrophic. On average, inorganic phosphorus fractions comprised the largest fraction (63%), while organic‐bound phosphorus (Org ≈ P) constituted 37% of the TP in Lake Mogan. The most important phosphorus‐immobilizing factors are high iron content (14 200–47 750 µg g^?1 DW), the sediment's clay content (47.80–51.80%), and an abundance of macrophytes at the sampling station. The low abundance of benthic macroinvertebrates (510–850 individuals m^?2), which depend on sediments with high iron and low organic matter (5.42–13.30%), played a role in the sediment phosphorus retention. Although bacterial abundance in the surficial sediment appeared to be positively correlated to temperature, the overlying water did not experience anoxic conditions, supporting a state in which bacteria were able to retain phosphorus in their cell structures. Long‐term changes in the sediments of Lake Mogan must be monitored lake. In order to optimize the management of the lake, and to determine the longevity of a clearwater state following management measures and continued external phosphorus loading, long‐term changes in the sediments of Lake Morgan must be monitored.     

Forms of particulate phosphorus in suspension and in bottom sediment in the Danube Delta

In the summer of 1995, samples of suspended solids and bottom sediments were collected from the lower course of the Danube, downstream from potential pollution sources such as tributaries draining industrialised and densely populated watersheds (the Jiu, Olt, Arges and Ialomita rivers) or big cities on the border of the river (Tulcea, Galati, Braila), and from the Danube Delta. Chemical and toxicological analyses were carried out on these samples. In the present paper, the results of the measurements of the forms of particulate phosphorus are discussed. Phosphorus occurring in the bottom sediments and the suspended solids has various origins and chemical forms. These forms may be operationally defined as: organic phosphorus (OP ) , apatite inorganic phosphorus (AP) and non‐apatite inorganic phosphorus (NAIP). The AP shows low variability, ranging from 350 to 400 p.p.m. for suspended solids and from 425 to 500 p.p.m. for bottom sediments. This is essentially due to the detrital origin of this form. These values are typical for freshwater sediments in European rivers. The NAIP, which originates both from natural sources and from human pollution, shows a high variability. This indicates that the nutrient pollution is derived from both point and non‐point sources in the watershed. The NAIP concentrations of 800 p.p.m. (Vadul Oii) and 850 p.p.m. (Oltenita) are very high (fourfold the average for European rivers), indicating that strong anthropogenic sources of phosphorus are present in the lower Danube watershed. As the NAIP is potentially bioavailable, its high concentration may contribute to eutrophication in the lower Danube and the Danube Delta.     

三峡库区香溪河消落带土壤磷时间动态研究

为探讨水华主要影响因子对三峡水库支流及库湾水华发生的影响,根据三峡库区水位变动规律,在香溪河消落带连续2 a(2013~2014年)开展了土壤磷素采样分析,并探讨了磷形态之间及其与土壤理化性质之间的相关性。研究结果显示:(1)2个水位涨落周期内,香溪河消落带土壤TP、水溶性磷(WS-P)、Al-P、闭蓄态磷(O-P)和Ca-P平均含量分别为749.43±56.43,9.05±1.10,26.41±5.55,46.62±7.57,112.49±17.47,228.76±11.26 mg/kg;消落带土壤中钙磷Ca-P和O-P是无机磷(IP)的主要赋存形态,Ca-P/IP均值为53.27%,O-P/IP均值为26.52%。(2)2014年消落带土壤TP和Ca-P与2013年相比呈增加的趋势;2个水位涨落周期内,土壤Al-P在泄水期含量显著高于出露期和蓄水期,而Fe-P在蓄水期含量显著高于泄水期和出露期(p0.05),两者呈相反的消涨趋势;消落带各海拔高程磷形态含量有所差异,变异系数分析表明,周期性淹水可导致消落带不同高程磷形态含量的变化,并增加了其分布的空间异质性。(3)冗余分析(RDA)排序和相关性分析得出p H是影响Ca-P的主要因素,土壤p H偏碱性是导致土壤Ca-P含量上升的重要原因;土壤有机质(SOM)是影响Al-P,Fe-P,O-P含量的主要因素;Al-P,Fe-P含量呈显著性正相关,而均与Ca-P含量呈显著性负相关(P0.05)。     

升钟湖夏季水和沉积物中磷形态分布特征

为探究升钟湖水和沉积物中磷污染情况,于2019年8月(夏季),采集了升钟湖湖区15个样点的水样和沉积物样品,测定了升钟湖表层水、间隙水及沉积物的磷形态,并分析各种形态磷之间的相关性。结果表明:①升钟湖表层水总磷含量介于0.033～0.085 mg/L,各形态的磷含量由高到低依次为DTP(61.93%)、DOP(40.00%)、PP(38.07%)和DIP(21.93%);②间隙水的总磷含量介于3.49～7.57 mg/L,是水体磷的“源”,正磷酸盐仅占总磷的1.9%;③沉积物总磷含量介于299.04～1 138.69 mg/kg,Psenner法连续分级提取出表层沉积物共有5种形态的磷,各形态磷含量由高到低依次为残渣磷(Res-P:44.78%)、金属氧化物结合态磷+有机碎屑腐殖酸磷(NaOH-P:22.92%)、钙结合态磷(HCl-P:14.82%)、可还原态磷(BD-P:13.39%)和弱吸附态磷(NH₄Cl-P:4.09%),各形态磷含量均表现一定的空间分布差异,其中,总磷含量整体为西北部高于东南部;④相关性分析结果显示,沉积物中磷的释放主要通过BD-P、N...     

宜兴三氿沉积物氮形态分布及其影响因素

为了解宜兴三氿(西氿、东氿和团氿)沉积物氮形态分布及其影响因素,采用连续分级提取法对三氿12个采样点表层沉积物样品中各种形态氮含量进行测定,探讨了不同形态氮的空间分布特征及影响因素。结果表明:总氮的空间分布与沉积物有机质分布存在明显的一致性,团氿含量较高,东、西氿含量较低且基本持平;可转化态氮含量占总氮的59.5%,对水体潜在危害较大,空间分布呈现出西氿最大、东氿次之、团氿最低的趋势;可转化态氮中4种形态氮含量大小顺序为弱酸可提取态氮、离子交换态氮、强碱可提取态氮、强氧化剂可提取态氮,弱酸可提取态氮为可转化态氮的优势形态;沉积物有机质与总氮和强氧化剂可提取态氮呈极显著正相关关系(P 0.01),pH值与总氮呈显著负相关关系(P 0.05);上覆水总氮与离子交换态氮呈极显著正相关关系(P 0.01),与可转化态氮呈显著正相关关系(P 0.05)。     

Use of sediment elemental and isotopic compositions to record the eutrophication of a polymictic reservoir in central Texas, USA

Paleolimnological studies are rarely performed on reservoirs because of concern that sediments might not accurately chronicle reservoir history. Eutrophication indicators might behave differently in polymictic reservoirs and stratified natural lakes because of system and/or mixing regime differences. Particulate organic carbon (POC), particulate organic nitrogen (PON), and total phosphorus (TP) concentrations, carbon:nitrogen (C:N) and nitrogen:phosphorus (N:P) ratios, and carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotopes from a sediment core were measured to demonstrate that sufficient information can be derived from sediments to permit a historical reconstruction. The scattered POC data were likely biased by seasonal/annual variability in allochthonous organic matter (OM) loading. The upwardly increasing PON in the sediment core supported historic primary productivity (PP) data, suggesting PON could be a better PP indicator than POC. The upwardly increasing TP documented historic P enrichment. The upwardly decreasing C:N ratio identified an OM source shift from allochthonous to increasingly autochthonous sources with reservoir age. The upwardly increasing N:P ratio implied that N‐fixation rates have increased with reservoir age, to compensate for increasing N limitation as the P loading increased. The δ¹³C decreased as the PP increased with reservoir age producing an atypical relationship compared to stratified natural lakes. The OM source shifts likely biased the δ¹³C–PP relationship, and might weaken δ¹³C‐inferred PP reconstructions in similar reservoirs. The δ¹⁵N increased with reservoir age, likely resulting from dissolved inorganic N (DIN) source changes, rather than nitrate utilization. Watershed urban growth and dairy operation intensification potentially contributed greater loads of isotopically heavy DIN. This study demonstrated that paleolimnology has great potential to assist eutrophication assessment and management efforts in reservoirs.     

Phosphate Characteristics and Bioavailability of Suspended Sediments from Streams Draining into Lake Erie

Suspended sediments from major U.S. tributaries draining into Lake Erie were analyzed for phosphorus. Analyses included: sediment concentration, reactive and total filtered P, and total P on water samples. Recovered sediment total P was determined by perchloric and persulfate extraction. Sediment was fractionated for NaOH-P citrate-dithionite-bicarbonate (CDB)-P, HCl-P, and organic P. New York streams had the highest suspended solids and the lowest content of most sediment fractions except HCl-P. NaOH-P and CDB-P were highest in sediments from Ohio tributaries; these fractions are considered to be bioavailable with NaOH-P more available than CDB-P. Digestion with perchloric acid consistently removed more P than the persulfate method. The difference in the two methods was negatively correlated with HCl-P.