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1.
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
2.
平水期洞庭湖不同形态磷赋存特征 总被引：4，自引：0，他引：4
通过现场调查和室内实验,对平水期洞庭湖24个断面上覆水-沉积物磷的污染程度、分布特征进行研究;同时,分析了各形态磷间的相关性,探讨了磷的赋存形态对水体富营养化的影响、沉积物释放量和释放风险。结果表明,水体内总磷分布规律为南洞庭西洞庭东洞庭大通湖,东洞庭湖以颗粒态磷为主,西洞庭湖、南洞庭湖、大通湖均以溶解态磷、无机磷为主。沉积物中总磷的分布规律为南洞庭西洞庭东洞庭大通湖。东洞庭湖、西洞庭湖、南洞庭湖则以Ca-P为主,大通湖以Fe/Al-P为主。Ca-P与Fe/Al-P呈现较显著的负相关关系。大通湖释放风险较大,可释放量大;东洞庭湖有一定的可释放量,应对这两个湖泊给予较多的关注。与国内其他湖泊比较,洞庭湖沉积物中TP处于中下水平,IP在沉积物中占据较高比例。湖区沉积物中Fe/Al-P与水体中DIP、DTP、TP均具有较显著的负相关关系,存在磷的内源释放。 相似文献
3.
湖泊沉积物中三种磷提取方法比较 总被引：3，自引：1，他引：2
水体沉积物中磷的分级提取没有统一的方法,大多数的提取方法只对沉积物中无机磷(IP)进行了研究,有机磷(OP)是作为一个整体被研究,OP的形态尚不清楚。文章探讨了SMT法、Ivanoff法和Golterman法三种方法对湖泊沉积物中磷形态提取的特征,分析了各方法应用于IP和OP形态提取的联系和差别。结果表明SMT法提取的钙磷(Ca-P)是Golterman法提取Ca-P的16倍,Golerman法提取的铁铝结合态磷(Fe/Al-P)是SMT法提取的近3倍。从OP提取结果来看,Goterlman法>Ivanoff法>SMT法,Golterman法和Ivanoff法提取的酸可提取有机磷相差较大,其他形态OP含量则相当。研究结果对于沉积物磷形态分析提取方法的合理选择具有指导意义。 相似文献
4.
太湖及其主要入湖河流沉积磷形态分布研究 总被引：57，自引：6，他引：57
选择了我国第三大浅水湖泊--太湖及其主要入湖河流进行沉积磷形态的连续提取研究.太湖湖区沉积磷中不稳态磷(LP)及铝结合态磷(Al-P)含量很低,其余形态磷为铁结合态磷(Fe-P)＜钙结合态磷(Ca-P)＜有机磷(Org-P).河流沉积物中有机磷的相对含量高于湖泊沉积物,绝对含量平均值约为湖泊沉积物的3.9倍,铁结合态磷的绝对含量约为湖泊沉积物的3/4,湖区沉积物Fe-P含量与水体中PO3-4-、Chla呈显著正相关关系,同时与间隙水的氧化性呈显著负相关关系.太湖各湖区沉积物的磷形态表现为空间差异较大,活性组分的差异性要大于活性较差的组分.总的来说北部湖区沉积物中Fe-P和Org-P含量高于其他湖区,这与太湖北部湖区水体高营养级和藻类爆发关系密切.湖区沉积磷的垂直分布规律较复杂,既有随深度增加的,也有随深度降低的,河流沉积物同样如此.这与太湖及河流生态条件、污染物排放以及沉积动力学条件不同有关. 相似文献
5.
河流输送是受纳水体中磷的主要来源,不同水文条件对其输送有很大影响。选择巢湖典型入湖河流丰乐和柘皋,在不同水文条件下,即非洪水期（丰乐和柘皋）、洪水涨水段（丰乐）与退水段（柘皋）对河水和沉积物进行分布式采样,测定磷的不同形态。其中,河水测定总磷（TP）和可溶性磷（DP）,沉积物测定总磷（TP）、无机磷（IP）、有机磷（OP）、铁铝磷（Fe/AL-P）和钙磷（Ca-P）。结果表明：非洪水期丰乐和柘皋河河水和沉积物中TP含量均为柘皋河高于丰乐河,两河都存在着富营养化风险,两河沉积物IP含量都显著高于OP。IP中,柘皋河Fe/Al-P含量略高于Ca-P,丰乐河相反。洪水涨水期,丰乐河河水TP和DP含量显著高于其非洪水期含量,沉积物不同形态磷均值含量较非洪水期略有降低,表明洪水涨水段降雨径流对不同来源磷冲刷、输送和泛起作用;洪水退水期,柘皋河河水TP和DP含量低于其非洪水期含量,河道沉积物不同形态磷均值含量较非洪水期有所升高,表明在退水段以稀释和沉淀作用为主。 相似文献
6.
7.
长江河口及其上海岸带水体沉积物中磷的存在形态 总被引：13，自引：0，他引：13
讨论了磷的 5种存在形态及其分布规律。河口及岸带水体沉积物中磷主要是以有机磷 (OP)和无机磷 (IP)形式存在的 ,有机磷是有机质的组成部分 ,无机磷又可分为可溶性磷(DP)、铁结合磷 (Fe P)、铝结合磷 (Al P)、钙结合磷 (Ca P)。研究发现 ,沉积物中总磷含量水平在 6 92 79～ 1570 99μg/g之间 ,无机磷含量在 2 2 0 0 2～ 92 8 33μg/g之间 ,占总磷含量的31 8%～ 6 0 5% ,而有机磷含量在 394 89～ 6 4 2 6 6 μg/g之间 ,为总磷含量的 39 5%～ 6 8 2 %。在分析水体沉积物中各形态磷的含量和变化的基础上 ,对磷在时空上的变化、与有机碳、总氮的关系以及污水输入影响等进行了初步的论述 ,并提出沉积物中铁结合磷 (Fe P)和铝结合磷 (Al P)可作为判断污染的指标之一。 相似文献
8.
采用7步连续浸提法对库布齐沙漠响沙湾沙粒中磷的各种存在形态进行了分析测定，并对沙粒样进行了分级形态研究。结果表明：在库布齐沙漠响沙湾沙粒中总磷（TP）的含量为137．21～362．09μg／g，其主要成分为无机磷（IP），平均占TP的比例为94．60％；而有机磷（Or—P）的含量为7．88～19．12μg／g，平均占TP的5．40％。在所有不同粒度的沙样中，自生钙结合磷（Ca—P）含量最高，占TP的58．95％～80．05％，其次是原生碎屑磷（De—P）。占TP的8．13％～30．22％，二者占IP的绝大部分；其他各形态磷含量的高低顺序为：有机磷（Or—P）〉吸附态磷（Ads—P）〉铁结合态磷（Fe—P）〉闭蓄态磷（Obs—P）〉铝结合态磷（AI—P）。在所取沙漠颗粒物样中TP、Ca—P、De—P、Or—P、AI—P各自的含量都是随颗粒物粒度的减小而增大，而Ads—P含量则相反；Fe—P、Obs—P的含量受颗粒物粒度变化的影响不大。 相似文献
9.
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
10.
滇池现代沉积物中磷的地球化学及其对环境影响 总被引：47，自引：2，他引：47
湖泊沉积物中,磷是产生富营养化的重要元素.湖泊中磷元素含量、地球化学行为以及它的复杂矿物学特征,使人们对磷的研究极为重视.滇池湖中总磷超标10.3倍,底泥沉积物中P2O5平均含量0.52%,最高可达1.92%.滇池地处磷矿区,是磷质来源最丰富的湖泊,统计表明,磷含量每年在不断增长.滇池沉积物中磷主要以吸附态、有机态、铁结合态、钙结合态、铝结合态等几种形式存在.这些形态磷在底泥中是不稳定的,它们在环境改变条件下,又将磷释放到水体中.微生物在磷的循环过程中起了重要作用,乳酸菌对不溶性磷酸盐的分解,使湖泊中可溶磷含量增高.聚磷菌对磷元素的富集以及聚磷菌死亡后发生有机磷的矿化作用,是湖泊中水合磷酸盐矿物沉积的重要途径.当湖泊中这种不稳定的水合磷酸盐矿物在条件具备的情况下,经沉积物覆盖成岩作用后,最终形成磷灰石。 相似文献
11.
The distribution of dissolved and particle-bound phosphorus (P) was investigated in the Elbe estuary during March 1995. The forms of particulate P were studied with a sequential extraction technique. Organic P dominated particle-bound P in the outer reaches of the estuary (52%), decreased to a minimum of 21% in the turbidity zone, and increased to 33% further upstream. Fe-bound P was the second most important P species in the outer reaches (27%) and dominated in the turbidity zone (up to 57%) and upstream of the turbidity zone (up to 48%). The P:Fe ratio increased with decreasing salinity, from 0.11 in the outer reaches to about 0.22 at zero salinity. Dissolved inorganic P release from reverine suspended matter was about two to three times larger than release, from marine suspended matter and was dominated by release of Fe-bound P. Dissolved inorganic P release from marine and from riverine organic matter were of equal importance. Because marine suspended matter dominates in the estuary, this suggests riverine organic matter is remineralized much faster than marine organic matter. This is in line with the refractory nature of marine organic matter (no phytoplankton bloom) and the easily degradable character of the riverine suspended matter (phytoplankton bloom) in the Elbe estuary during March 1995. 相似文献
12.
13.
Impact of fertilizer phosphorus application on phosphorus release kinetics in some calcareous soils 总被引：1，自引：0，他引：1
Phosphate reactions and retention in the soil are of paramount importance from the perspective of plant nutrition and fertilizer
use efficiency. The objective of this work was to study the kinetics of phosphorus (P) desorption in different soils of Hamadan
in fertilized and unfertilized soils. Soils were fertilized with 200 mg P kg−1. Fertilized and unfertilized soils were incubated at 25 ± 1°C for 6 months. After that, release of P was studied by successive
extraction with 0.5 M NaHCO3 over a period of 1,752 h. The results showed that phosphorus desorption from the fertilized and unfertilized soils began
with a fast initial reaction, followed by a slow secondary reaction. The amount of P released after 1,752 h in fertilized
and unfertilized soils ranged from 457 to 762.4 and 309.6 to 586.7 mg kg−1, respectively. The kinetics of cumulative P release was evaluated using the five kinetic equations. Phosphorus desorption
kinetics were best described by parabolic diffusion law, first order, and power function equations. Rate constants of these
equations were higher in fertilized than unfertilized soils. Results from this study indicate that release rate of P plays
a significant role in supplying available P and released P in runoff. 相似文献
14.
过铝质岩浆-热液演化体系中磷的地球化学行为 总被引：1，自引：0，他引：1
泥质岩部分熔融产生的过铝质岩浆中的P2O5含量受控于源区磷灰石含量、部分熔融程度和岩浆中磷灰石的溶解度.过铝质岩浆中的Ca、REE以及Y的活度低,阻碍了磷灰石、独居石以及磷钇矿等的结晶,碱性长石成为过铝质岩浆中P的主要寄主矿物,直到岩浆演化晚期,Li的活度增大,P才与Li形成磷铝锂石-羟磷铝锂石.进入以晶体、熔体和流体相共存为特征的岩浆-热液过渡阶段体系后,P的地球化学行为主要受流体/熔体相分配的制约,P优先进入到熔体相, 不太可能形成富P的流体.在热液阶段,长石晶体在Al-Si有序化过程中释放的结构P与流体介质所携带的Ca离子形成次生磷灰石.在热液蚀变过程中所形成的富P流体,很可能是某些Sn、W、Mn和U热液矿床的主要载体. 相似文献
15.
From February 1992 until June 1993, the distribution of dissolved and particulate phosphorus and nitrogen was investigated in the Ems estuary at approximately monthly intervals. Nutrient import was quantified from the river load. Nutrient export to sea was quantified from river discharge and from the salinity-nutrient gradient in the outer estuary. In addition, sediment cores were taken from four sites along the main axis of the estuary in October 1992. On the basis of these data a nitrogen and phosphorus budget was made. On an annual basis, 45 × 106 mol P and 2,360 × 106 mol N are imported into the Ems estuary. Freshwater runoff is the main source of input, accounting for about 92% of the nitrogen input and 71% of the phosphorus input. Import of particulate phosphorus from the sea is important in the phosphorus budget (27%). Seventy-five percent of the nitrogen input is transported to the North Sea. Denitrification is the major loss factor (19% of the nitrogen input), and burial explains 6%. Of the phosphorus input, 60% is transported to the North Sea and 40% accumulates in the sediment. Nitrogen import during summer explains about one third of the annual primary production, indicating that nitrogen turn over is about three times. Phosphorus import during summer explains less than 16% of the annual primary production. We suggest that trapping of particulate P and adsorption onto Fe(oxy)hydroxides during the entire year and the release of Fe-bound P during summer after reduction of Fe(oxy)hydroxides is instrumental in sustaining high primary production, which could not be sustained if it depended only on P imported during the growing season. 相似文献
16.
Fractionation of phosphorus in the sediments of the Cochin estuary situated along the southwest coast of India was studied by applying sequential chemical extraction. The different forms of phosphorus were estimated seasonally (premonsoon, monsoon, and postmonsoon) under eight different schemes. The major forms of phosphorus analyzed were exchangeable P, anion exchangeable P, carbonate-bound P, labile and resistant organic P, Fe and Al P, calcium-bound P, and hydrolyzable surplus P. Quantitatively, the above fractions in isolation or in combination vary in content due to chemoestuarine variability and seasonal fluctuations. Changes in speciation have been noted in association with salinity variations in the waterway, especially following enhanced river runoff during the monsoon. The chemical forms of the sediment-bound phosphorus in the northern parts of this estuary have been shown to be modified by nonpoint sources. Sediment P fractionation defines the role of chemical speciation of phosphates (as nutrients) and is indicative of the processes controlling the pathways of P into the coastal waters. The changes in the exchangeable P, together with marked regional variations in calcium-bound P, exemplify the complex estuarine variability of phosphorus. Enhanced amounts of exchangeable P mark its appearence in high saline waters, signifying the presence of biologically available nutrient phosphorus. The calcium-bound P and hydrolyzable surplus P show significant relation with sediment organic carbon and Fe whereas other forms do not exhibit any marked covariation. The Ca and Na NTA extraction scheme is very specific in its selectivity. 相似文献
17.
Zoning of phosphorus in igneous olivine 总被引：2，自引：2，他引：0
Margaret S. Milman-Barris John R. Beckett Michael B. Baker Amy E. Hofmann Zachary Morgan Meghan R. Crowley Daniel Vielzeuf Edward Stolper 《Contributions to Mineralogy and Petrology》2008,155(6):739-765
We describe P zoning in olivines from terrestrial basalts, andesites, dacites, and komatiites and from a martian meteorite.
P2O5 contents of olivines vary from below the detection limit (≤0.01 wt%) to 0.2–0.4 wt% over a few microns, with no correlated
variations in Fo content. Zoning patterns include P-rich crystal cores with skeletal, hopper, or euhedral shapes; oscillatory
zoning; structures suggesting replacement of P-rich zones by P-poor olivine; and sector zoning. Melt inclusions in olivines
are usually located near P-rich regions but in direct contact with low-P olivine. Crystallization experiments on basaltic
compositions at constant cooling rates (15–30°C/h) reproduce many of these features. We infer that P-rich zones in experimental
and natural olivines reflect incorporation of P in excess of equilibrium partitioning during rapid growth, and zoning patterns
primarily record crystal-growth-rate variations. Occurrences of high-P phenocryst cores may reflect pulses of rapid crystal
growth following delayed nucleation due to undercooling. Most cases of oscillatory zoning in P likely reflect internal factors
whereby oscillating growth rates occur without external forcings, but some P zoning in natural olivines may reflect external
forcings (e.g., magma mixing events, eruption) that result in variable crystal growth rates and/or P contents in the magma.
In experimental and some natural olivines, Al, Cr, and P concentrations are roughly linearly and positively correlated, suggesting
coupled substitutions, but in natural phenocrysts, Cr zoning is usually less intense than P zoning, and Al zoning weak to
absent. We propose that olivines grow from basic and ultrabasic magmas with correlated zoning in P, Cr, and Al superimposed
on normal zoning in Fe/Mg; rapidly diffusing divalent cations homogenize during residence in hot magma; Al and Cr only partially
homogenize; and delicate P zoning is preserved because P diffuses very slowly. This interpretation is consistent with the
fact that zoning is largely preserved not only in P but also in Al, Cr, and divalent cations in olivines with short residence
times at high temperature (e.g., experimentally grown olivines, komatiitic olivines, groundmass olivines, and the rims of
olivine phenocrysts grown during eruption). P zoning is widespread in magmatic olivine, revealing details of crystal growth
and intra-crystal stratigraphy in what otherwise appear to be relatively featureless crystals. Since it is preserved in early-formed
olivines with prolonged residence times in magmas at high temperatures, P zoning has promise as an archive of information
about an otherwise largely inaccessible stage of a magma’s history. Study of such features should be a valuable supplement
to routine petrographic investigations of basic and ultrabasic rocks, especially because these features can be observed with
standard electron microprobe techniques. 相似文献
18.
R. M. Chambers J. W. Fourqurean J. T. Hollibaugh S. M. Vink 《Estuaries and Coasts》1995,18(3):518-526
Allochthonous inputs of suspended particulate matter from freshwater environments to estuaries influence nutrient cycling and ecosystem metabolism. Contributions of different biogeochemical reactions to phosphorus dynamics in Tomales Bay, California, were determined by measuring dissolved inorganic phosphorus exchange between water and suspended particulate matter in response to changes in salinity, pH, and sediment redox. In serum bottle incubations of suspended particulate matter collected from the major tributary to the bay, dissolved inorganic phosphorus release increased with salinity during the initial 8 h; between 1–3 d, however, rates of release were similar among treatments of 0 psu, 16 psu, 24 psu, and 32 psu. Release was variable over the pH range 4–8.5, but dissolved inorganic phosphorus releases from sediments incubated for 24 h at the pH of fresh water (7.3) and seawater (8.1) were similarly small. Under oxidizing conditions, dissolved inorganic phosphorus release was small or dissolved inorganic phosphorus was taken up by particulate matter with total P content <50 μmoles P g?1; release was greater from suspended particulate matter with total phosphorus content >50 μmoles P g?1. In contrast, under reducing conditions maintained by addition of free sulfide (HS?), dissolved inorganic phosphorus was released from particles at all concentrations of total phosphorus in suspended particulate matter, presumably from the reduction of iron oxides. Since extrapolated dissolved inorganic phosphorus release from this abiotic source can account for only 12.5% of the total dissolved inorganic phosphorus flux from Tomales Bay sediments, we conclude most release from particles is due to organic matter oxidation that occurs after estuarine deposition. The abiotic, sedimentary flux of dissolved inorganic phosphorus, however, could contribute up to 30% of the observed net export of dissolved inorganic phosphorus from the entire estuary. 相似文献
19.
以氢氧化钾熔融分解样品，以热水浸提、铁、铜、钴、镍等干扰物进入沉淀而与磷分离，然后在7％的硝酸介质以钼酸铵铵及偏钒酸铵混合显色剂显色测定磷的含量，该方法简便、稳定、快速、适合于铁、锰矿中磷的测定。 相似文献
20.
Comparison between the lower Nansi Lake and its inflow rivers in sedimentary phosphorus fractions and phosphorus adsorption characteristics 总被引：1，自引：1，他引：0
Zhi-bin Zhang Xiao-bo Tan Lei-lei Wei Shi-miao Yu Dao-ji Wu 《Environmental Earth Sciences》2012,66(5):1569-1576
There were many differences between rivers and lakes such as flow velocity, hydraulic retention time, water vegetation community
and other chemical-physical factors that may lead to different characteristics of sedimentary phosphorus. In our research,
sedimentary phosphorus fractions and its phosphorus adsorption differences between the lower Nansi Lake and its main inflow
rivers were compared. The results showed that the contents of NaOH-P, Org-P, IP-P, and TP in lake sediments were obviously
higher than those in its inflow river sediments while HCl-P had no obvious difference between them. Based on analysis, the
unstable NaOH-P would accumulate in lake sediments, while it is difficult for it to retain in sediments of rivers because
of a high frequency of flood flows and unstable bed sediments. In addition, water vegetation communities were helpful in the
accumulation of Org-P in lake sediments. From phosphorus adsorption experiments results, the Ceqc (equilibrium concentration
of phosphorus release/adsorption) of lake sediments was higher than that of river sediments. It was indicated that sedimentary
phosphorus would be more easily released from lake sediments than river sediments. So in future more work should be focused
on internal P loading from lake sediments release. 相似文献