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1.
鄱阳湖沉积物中磷的赋存形态及分布特征 总被引：11，自引：2，他引：9
利用分级提取法对鄱阳湖沉积物进行了磷形态的分级提取和测定,系统研究了沉积物中磷的赋存形态及分布特征.结果表明,鄱阳湖表层沉积物中磷的赋存形态主要包括铁磷(Fe-P)、钙磷(Ca-P)、铝磷(Al-P)、可溶性磷(DP)等无机磷(IP)及有机磷(OP),各形态磷的空间分布基本具有从河口地区监测点向湖区监测点方向升高的趋势,垂向分布上总磷及各形态磷含量随深度增加而降低.表层沉积物(0-2cm)中总磷含量为578.36-813.55mg/kg,主要由无机磷组成,无机磷中以Fe-P含量最高,最大值达350.24mg/kg,占总磷的40%以上,Ca-P、Al-P含量相当,约占总磷含量的20%左右,而以DP的含量最低,含量在5%以下.有机磷含量约占总磷含量的15%左右.另外,沉积物中TP含量与Fe-P、Al-P、Ca-P及OP均具有较好的相关性,且OP含量与Fe-P、Al-P也具有较好的正相关关系,而与Ca-P的相关性较弱. 相似文献
2.
长江中下游湖泊沉积物生物可利用磷分布特征 总被引：24，自引：5，他引：24
利用化学提取方法对太湖6个样点,巢湖4个样点和龙感湖3个样点的表层沉积物和沉积物柱样进行了生物可利用磷(BAP)测定．北太湖表层沉积物的平均含量为259．5mg／kg,而西部湖区平均含量为114 6mg／kg,湖心区平均含量为40．6 mg/kg,而东太湖平均含量为50．7 mg／kg,呈显著北高南低的特点．巢湖西部湖区表层沉积物的BAP平均含量为 254．2 mg／kg,而东部湖区BAP含量降低为101．9mg／kg．龙感湖表层沉积物BAP平均含量为67．8 mg／kg．显著表明污染程度较高的湖区沉积物的BAP相应较高．BAP在沉积物中随深度呈指数降低,显示生物可利用磷在沉积作用下向稳定的非活性磷转化．夏季沉积物中的BAP由于生物活性的增强向溶解态活性磷转化过程增强,显示为较低的BAP含量．BAP 含量与水体溶解态活性磷呈正相关关系,且该相关性在BAP含量较低的样点好于高BAP的样点． 相似文献
3.
水体砷污染及其健康危害已成为一个备受关注的环境问题.本研究通过测定洞庭湖主要河口区表层沉积物砷含量、河蚬砷及砷形态（亚砷酸盐As（Ⅲ）、砷酸盐As（Ⅴ）、甲基砷酸MMA、二甲基砷酸DMA和砷甜菜碱AsB）含量，对表层沉积物砷的潜在生态风险和河蚬食用健康风险进行评价.结果表明，洞庭湖主要河口区表层沉积物砷含量在11.47~61.20 mg/kg之间，其水平分布规律表现为：南洞庭湖>东洞庭湖>西洞庭湖.河蚬砷含量范围为6.36~11.15 mg/kg，各砷形态含量排序为：AsB > As（Ⅴ） > DMA > As（Ⅲ） > MMA，各样地间不存在显著性差异.应用潜在生态风险指数法对表层沉积物中砷的潜在生态风险进行评价，各样地的潜在生态风险指数均值为23.09，潜在生态风险程度属于轻微级别.同时，利用致癌风险指数（CR）和危熵系数（HQ）评价经河蚬摄入无机砷给人体带来的潜在健康风险.洞庭湖主要河口区河蚬中无机砷的致癌风险CRiAs值达到了1.36×10-3~3.43×10-3（平均值为2.24×10-3），均显著超过USEPA推荐的可接受风险水平上限值（1×10-4），其危熵系数HQiAs值达到3.01~7.61（平均值为4.98，约为标准值的5倍），说明长期食用当地河蚬具有较高的致癌和非致癌健康风险.本研究结果对于了解洞庭湖沉积物和底栖动物的砷污染现状和风险水平具有重要意义，为该流域的砷污染控制及治理提供科学依据. 相似文献
4.
基于2013 2015年调查获取的129个洞庭湖表层沉积物和底栖生物的调查数据,应用筛分水平浓度法初步探讨了洞庭湖沉积物几种重金属沉积物质量基准的推荐值.结果表明,洞庭湖沉积物砷(As)、镉(Cd)、铬(Cr)、铜(Cu)、铅(Pb)和锌(Zn)含量均值为17.2、2.63、56.9、32.4、38.4和96.3 mg/kg(DW);筛分水平浓度法获取的洞庭湖沉积物As、Cd、Cr、Cu、Pb和Zn质量基准分别为11.97、1.13、42.03、19.17、23.63和67.54 mg/kg(DW).通过与不同国家及地区指定的重金属质量基准推荐值以及本地区采用其他方法推导的重金属基准推荐值进行比较,推算出本研究获取的6种重金属沉积物质量基准推荐值接近所有数据的中间值.对于洞庭湖流域,不同方法获取的沉积物重金属质量基准具有可比性.然而,鉴于用于推导沉积物质量基准的数据采集涉及的区域较为有限,且除了重金属污染外,影响底栖生物分布的因素较为复杂,导致获取的沉积物重金属质量基准推荐值存在一定的不确定性. 相似文献
5.
红枫湖、百花湖沉积物全氮、可交换态氮和固定铵的赋存特征 总被引：34，自引：5，他引：34
氮是引起湖泊水体富营养化的关键营养元素之一。本次工作从贵州两个重要水库（红枫湖和百花湖）采集了未受扰动的沉积物样品性，分析了分层沉积物样品中的总氮，无机交换性氮和固定铵的含量及垂直剖面分布，研究表明，红枫湖和百花湖沉积物中具有较高的全氮含量，平均含量约为沉积物干重的0.36%～0.40%，其垂直分布在埋藏过程中受到成岩作用改造，沉积物交换性氮在沉积物中的赋存受到全氮含量和埋藏环境的双重控制，红枫湖和百花湖沉积物具有较强的吸持固定铵的能力，沉积物固定铵的绝对含量的平均值分别为434.05mg/kg和416.94mg/kg，分别占全氮的13.53%和12.53%。 相似文献
6.
7.
湖泊表层沉积物可溶性有机氮含量及分布特性 总被引：8，自引：1，他引：7
选择鄱阳湖、洞庭湖等6个湖泊的15个表层沉积物样品,用1mol/L KCl溶液提取沉积物中的可溶性有机氮(SON),并研究了SON的含量、分布状况及特性.结果表明,所研究的沉积物SON含量变异较大,在17.18-292.31mg/kg之间波动,平均为134.45 mg/kg,占可溶性总氮(TSN)的51.86%,沉积物总氮的7.14%.污染程度重的沉积物中SON含量均较污染程度轻的高,且SON含量与TN、TSN含量呈正相关,即与沉积物氮污染程度呈正相关,分布状况则与湖泊污染程度、人类活动干扰强度等紧密相关,所研究表层湖泊沉积物巾游离氨基酸(FAA)含量处于4.69-42.04mg/kg间,平均为23.27mg/kg,占SON的18.80%,TN的1.24%,FAA与SON含量呈显著正相关,在沉积物中的平均含骨及在SON中的比例均较土壤中高,说明湖泊沉积物SON有较大的易分解组分,SON与沉积物可溶忭无机氮、有机质、CEC等显著相关,因此,SON是湖泊沉积物氮的重要组成部分,对湖泊富营养化具有重要的影响,特别是对污染严重的沉积物而言,更应重视其SON在湖泊氮循环及富营养化中的作用. 相似文献
8.
磷是坦噶尼喀湖生态系统中必不可少的营养元素,直接决定湖体初级生产力的高低,进而影响到周边居民对于动物蛋白的获取来源.为了解坦噶尼喀湖磷的外源输入,选择湖泊东北部的入湖河流,对表层沉积物(16个样点)中总磷(TP)和各形态磷含量及其分布特征进行分析,并探讨磷的形态分布特征与土地利用方式之间的相关关系.结果表明,入湖河流沉积物TP含量为73.05~239.94 mg/kg,平均含量为152.64±55.37 mg/kg,其中最高值出现在马拉加拉西河口.采用Psenner法对磷进行连续浸提并比较不同形态磷含量,由高及低依次为铁铝结合态磷(Fe/Al-P)钙结合态磷(CaP)有机磷(Org-P)残渣态磷(Res-P)弱吸附态磷(Labile-P).土地利用类型对TP及各形态磷含量影响较大,其中TP含量表现为河口湿地城镇附近林草地区,表明地表径流和人类活动会对TP含量产生影响,而对于不同形态磷含量,Laible-P、Fe/Al-P、Org-P含量均表现为河口湿地林草地城镇附近,Ca-P、Res-P含量均表现为城镇附近河口湿地林草地.分析沉积物理化性质与各磷形态之间的相关性,发现沉积物总氮(TN)、有机质和总有机碳与Fe/Al-P、LabileP和TP相关性较好,与Org-P、Ca-P和Res-P相关性较差,表明TN和有机质的输入,会伴随沉积物中磷含量的升高,其增量的赋存形态主要为氧化还原敏感态磷和Labile-P.沉积物粒径组成与各磷形态含量存在相关性,细粒径沉积物与各形态磷含量呈显著正相关,粗粒径沉积物与各形态磷呈显著负相关,表明细小颗粒更易吸附磷. 相似文献
9.
滇池水-沉积物界面磷形态分布及潜在释放特征 总被引：14，自引：3，他引：11
通过现场调查和室内模拟实验,对滇池35个上覆水-沉积物磷的分布特征以及沉积物中磷释放动力学特征进行研究,结果表明:滇池表层沉积物中不同形态磷含量表现为:有机磷(OP)(1482.49±1156.82 mg/kg)钙结合态磷(Ca-P)(865.54±558.40 mg/kg)金属氧化物结合态磷(Al-P)(463.77±662.18 mg/kg)残渣态磷(Res-P)(218.52±83.11 mg/kg)可还原态磷(Fe-P)(128.13±101.56 mg/kg)弱吸附态磷(NH4Cl-P)(2.26±3.05 mg/kg);滇池上覆水草海总磷浓度处于劣Ⅳ类水平,外海不同湖区总磷浓度介于Ⅳ~Ⅴ类之间;滇池水体中的磷以颗粒态磷含量最高;滇池表层沉积物中磷的释放是由快反应和慢反应两部分组成.释放过程主要发生在前8 h内;不同区域沉积物磷的最大释放速率、最大释放量、磷的释放潜力平均值均表现为:草海外海北部外海南部湖心区;滇池表层沉积物中磷的释放主要由NH4Cl-P、Fe-P、Al-P和OP进行,其中,NH4Cl-P和Fe-P所占比重较大;磷的释放与上覆水中溶解性总磷、溶解态无机磷和溶解态有机磷呈显著正相关,预示着上覆水中磷的迁移转化更多地受到水-沉积物界面浓度梯度的控制,进一步说明不能以总磷含量来评价湖泊磷素释放的状况,需与磷形态及分布特征相结合进行分析. 相似文献
10.
贵州红枫湖沉积物磷赋存形态的空间变化特征 总被引：11，自引：1，他引：10
选取贵州省红枫湖这一典型的亚深水型人工湖泊作为对象,研究了6个代表性湖区沉积物柱芯磷的赋存形态,结合水体温度和溶解氧现场监测结果,探讨了该类型湖泊沉积物内源磷释放风险.研究结果表明,红枫湖沉积物总磷含量普遍较高,表层沉积物总磷含量均值大于1500 mg/kg,明显高于下部沉积物.NaOH-SRP和rest-P是沉积物磷的主要赋存形态.NH4Cl-P和BD-P含量表层最高,随深度增加明显降低,rest-P含量在垂向上变化不大.人为活动是造成沉积物总磷及赋存形态空间分布差异的主要原因,工业废水和网箱养鱼活动等大大增加了沉积物NaOH-SRP含量.红枫湖深水湖区底部水温多在14.5～23.5℃之间,随季节变化底部水温差异明显,溶解氧含量通常不高于1.5 mg/L,整体处于季节性缺氧或厌氧状态.以NaOH-SRP为主的沉积物磷赋存形态和深水缺氧环境大大增加了红枫湖沉积物内源磷释放的风险,在未来的研究中亟待加强对该类型湖泊沉积物内源磷释放机制、控制因素及治理措施的研究. 相似文献
11.
模拟扰动条件下太湖表层沉积物磷行为的研究 总被引：75，自引：8，他引：75
利用恒温震荡器构筑的模拟扰动环境，研究了太湖水－沉积物界的磷释放和吸附行为。结果表明：表层沉积物的磷酸盐释放作用在模拟扰动条件下并不十分明显，在低强度的扰动条件下未观察到释放现象，模拟高强度扰动后，出现一个相对较强的释放过程，最大释放时沉积物上覆水浓度约为低强度扰动时的3倍，最大释放时间（Tmax)可能受磷酸盐形态分布的不同而有所差异，相比较而言，磷酸盐的吸附作用表现得十分明显迅速，沉积物上覆水磷酸盐浓度在0．5h后分别0229mg/L和l0.215mg／L下降为0．05mg/L和0.013mg/L，可以看出当上覆水磷酸盐浓度较高时，吸附作用的强度远大于释放作用，在25℃，模拟中等强度（100rpm)的模拟扰动条件下，当初始磷酸盐浓度为1．01mg/L时，梅梁湾和五里湖的表层沉积物吸附容量分别为每克千重吸附0．04mg和0.050mg磷酸盐，这种较高的吸附能力对浅水湖泊的磷酸盐缓冲作用能起到积极作用。 相似文献
12.
G. Proft 《洁净——土壤、空气、水》1994,22(4):177-184
The BSi content has been investigated in the surface sediments of lakes of different trophic state in the Mecklenburgian Lake District. The BSi content differs between 1 to 1000 mg BSi/g dry matter. High values were found in deep eutrophic lakes. Litoral sediments and shallow eutrophic lakes have lower contents. BSi content was found to be correlated with lake morphometry, depth, trophic level, sediment composition and especially with calcite. With the CaCO3/BSi-value, 3 groups of lakes can be characterized:
- CaCO3/BSi = 0 oligotrophic and dystrophic lakes
- CaCO3/BSi ≤ 10 mesotrophic and eutrophic deep lakes
- CaCO3/BSi ≤ 10 eutrophic shallow lakes
13.
The paleoenvironmental significance of spatial distributions of grain size in groundwater‐recharged lakes: A case study in the hinterland of the Badain Jaran Desert,northwest China 
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下载免费PDF全文 For lakes in desert hinterlands that are not recharged by river runoff, sediment input solely comes from wind transport. While the processes of sediment transport and deposition in these lakes differ significantly from those with river discharge, the spatial distribution of sediment grain size in these groundwater‐recharged lakes remains largely unknown. Moreover, whether the grain size distribution in these lake sediments can be used as a proxy in the study of past climatic change and environmental evolution studies is unclear. In this study, five lakes with a range of surface areas that had no runoff recharge were selected from the hinterland of the Badain Jaran Desert of north‐western China, and a total of 108 samples of lake surface sediments were collected to examine the spatial distribution of grain size. Moreover, an end‐member‐modeling algorithm was used to calculate end members from all grain size measurements. Our results showed that both the median and mean grain sizes in the lake sediments decreased from the nearshore to the offshore, deep‐water zone. However, the lowest median and mean grain sizes were not found in the center of the lakes, in contrast to lakes recharged by surface runoff. The median grain size of sediment in the lake center was negatively correlated with lake level, and thus could help reveal lake evolution at low resolutions. Moreover, EM1 and EM2 were interpreted as wind transported sediment, and sediment perturbed by lake waves after wind transport, respectively. The modal grain size of EM1 varied slightly between lakes, while changes in the modal grain size of EM2 were related to lake area. Given the positive relationship found between EM2 content and lake level, changes in the EM2 content (%) can serve as a rough indicator of lake level fluctuations at low temporal resolutions. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
14.
Little is known about the distribution and risk levels of nutrients and organic matter(OM) in the surface sediment of shallow submerged macrophyte-dominated lakes. In the current study, sixty surface sediment samples were collected from Xukou Bay, a typical submerged macrophyte-dominated zone in Lake Taihu, China. A 60-day degradation experiment of Potamogeton malaianus, a dominant species in the bay,was done in the laboratory. The results demonstrated that the ranges of total nitrogen(TN) and t... 相似文献
15.
Hubert Hellmann 《洁净——土壤、空气、水》2003,31(2):85-96
A Recent Contamination Trend: Polycylic Aromatic Hydrocarbons (PAHs) in Aquatic and Terrestrial Sediments Concentrations of polycylic aromatic hydrocarbons (PAHs) measured in aquatic sediments of small, medium‐sized or very large inland lakes, of estuaries as well as in terrestrial sediments from Germany, the UK, Finland, and the USA were plotted in 10 trend curves over the period from 1800 to 1990. The segments of the bore cores were dated for their deposition age. For comparability of the results, the trend is preferentially shown by the guide parameter fluoranthene. Until the 19th century, a constant background value of CFluo = 10…50 μg/kg was observed in all regions. Then a steep increase in concentration followed, reaching in the aquatic sediments a maximum in the period 1940 to 1965, while the individual fluoranthene values ranged widely from 90 to 2400 μg/kg. In several regions, a more or less distinct decrease superseded this maximum, although this development did not appear in terrestrial sediments, in one estuary, and in remote forest lakes in Finland. The trend curves reflect the atmospheric deposition of PAHs in airborne dust and in some cases the import through runoff via rivers. Thus, the sediment profiles depict the development of air pollution by pyrogenic contaminants over more than a century. Sediment profiles from rivers can be used only with a high degree of reservation, because of the irregularity and low representativity of the sedimentation. 相似文献
16.
The heavy metal inventory and the ecological risk of the estuarine sediments in Hailing Bay, an important maricultural zone along the southern coast of China, were investigated. Results show that the surface sediments were mainly polluted by As (2.17-20.34 mg/kg), Ni (1.37-42.50mg/kg), Cu (1.21-58.84 mg/kg) and Zn (11.69-219.22 mg/kg). Furthermore, the aquafarming zone was significantly more polluted than the non-aquafarming zone, and cluster analysis suggested additional sources of heavy metal input in the aquafarming zone. As, Cr, Cu, Ni, Pb and Zn were mainly present in the non-bioavailable residual form in the surface sediments, whereas Cd was predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd, and from As, Cu and Pb to less degrees. The highest potential risks occurred near the aquaculture base, indicating the need to control heavy metal inputs from aquafarming activities. 相似文献
17.
白洋淀沉积物氮磷赋存特征及其内源负荷 总被引：11，自引：2，他引：9
白洋淀环境整治对区域生态文明建设具有重要意义，然而，目前对加剧白洋淀富营养化的内源氮、磷污染负荷依然缺乏系统的研究.本研究以野外调研和室内培养实验相结合形式，在白洋淀主要水域内采集原位柱状沉积物样品，详细地研究了白洋淀沉积物中氮、磷赋存形态、间隙水中氮、磷剖面特征以及沉积物-水界面氮、磷交换特征.结果表明，白洋淀沉积物总氮、总磷含量分别为1230.8~9559.0 mg/kg（均值2379.5 mg/kg）和344.4~915.4 mg/kg（均值608.4 mg/kg），氮、磷累积污染量大.沉积物中铵态氮赋存量大（3.2~175.8 mg/kg），由此导致间隙水中铵态氮浓度较高，最高达到28.8 mg/L.沉积物磷形态以Ca-P和Fe-P为主，分别占总量的38.3%~76.1%和3.98%~18.0%，间隙水中磷酸盐浓度已接近甚至高于国内外典型富营养湖区.间隙水中高浓度的铵态氮和磷酸盐导致沉积物-水界面氮、磷交换通量较高，铵态氮平均释放和扩散通量分别为106.37和12.42 mg/（m2·d）；磷酸盐平均释放和扩散通量分别为15.06和2.33 mg/（m2·d），沉积物内源氮、磷污染负荷较高，已严重威胁到白洋淀水环境质量，迫切需要整治.其中，北部河口区域以及中部府河入湖区和人口密集活动区沉积物氮、磷内源负荷尤为突出，应成为白洋淀沉积物内源污染整治的关键区域. 相似文献