云南湖泊沉积与环境演变研究进展

云南湖泊因地理位置独特,所处地区气候类型多样,历来都是中国乃至世界湖泊研究的热点区。本文主要回顾了云南地区20世纪90年代以来湖泊沉积与环境演变方面所进行的相关研究,并着重对湖泊沉积研究中的新技术新方法应用、湖泊沉积对人类活动的响应、高分辨率的不同时间尺度的钻探研究、湖泊沉积与生物地球化学作用的关系等方面进行扼要综述,以了解其所取得的新进展,存在的问题和不足以及今后研究的主要内容和努力的方向。     

生物滞留系统去除城市地表径流中多环芳烃的研究进展

低影响开发(LID)生物滞留系统是净化城市地表径流的重要措施。多环芳烃(PAHs)作为难降解有机污染物,是城市雨水径流中的重要成分之一。通过总结城市地表径流中PAHs污染现状和国内外应用生物滞留系统去除PAHs的研究动态,系统分析了PAHs类污染物的去除机理、效果和影响因素。研究结果表明:生物滞留系统主要通过填料吸附、微生物降解、植物吸收、挥发等作用去除PAHs,平均去除率在30%~90%。影响去除效果的主要因素包括PAHs性质、系统组成与设计、微生物及环境因子等。建议关注生物滞留系统中PAHs的积累和长期运行效果,并开展系统优化设计和作用机制研究工作。     

Trace Organic Contaminants in the Detroit River

Concentrations of polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons (PNAs), chlorobenzenes (CBs), chlorophenols (CPs), and a number of other organochlorine compounds (OCs) have been determined in the surface microlayer, subsurface water, suspended solids, sediments, and in sediment pore water at 20 sampling stations in the Detroit River. The data are discussed in terms of contaminant sources, pathways, and sinks. Spatial trends within the river and relationships of contaminant groups within and between compartments are described. The results indicate a continuing input of all contaminant groups to the river from a variety of sources, particularly from sewage treatment plant effluents and several tributaries. The contaminant distributions and intercorrelations also indicate that major sources of PCBs, PNAs, OCs, and CBs are concentrated on the westerly river shore, while CPs enter the river mainly from the easterly shore.     

Distribution of Hydrocarbons and Chlorinated Hydrocarbons in Various Phases of the Detroit River

Concentrations of several chlorohydrocarbons, polychlorinated biphenyls, and polynuclear aromatic hydrocarbons in the Detroit River were measured. For purposes of this study, the river ecosystem was divided into six phases or compartments: sediments, pore water in the sediments, suspended solids, subsurface water, surface microlayer, and air. Significant amounts of the above mentioned compounds occur in all of these compartments except air (for which our detection was relatively insensitive). The sediments contained over 99% of the chlorinated compounds. The polynuclear aromatic hydrocarbons were distributed between the subsurface water and the sediments.     

湖泊沉积物砷生物有效性评估采样分析技术综述

为了给浅水湖泊砷(As)污染状况的评估和综合治理提供技术支撑,在分析As污染物在湖泊中的赋存形态、各形态之间的转化以及As生物有效性影响因素的基础上,对比分析了传统采样技术和原位采样技术的优劣。结果表明,传统采样技术极易在样品采集和测定过程中对As产生再吸附、再溶解和再分配,无法真实地反映As的污染状况和迁移转化过程,而原位采样技术中Peeper、DET、DGT等可较好地评估湖泊As污染的生物有效性,但这类技术忽视了沉积物和上覆水的交互作用,导致累计的过程中不能对目标元素直接量化,且忽略了微生物的变化对测量的影响,所以测定过程仍需进一步优化;传统的采样技术和新型的原位测定技术各自具有明显的劣势,因此多种采样分析技术的联用可减小As污染浓度误差。     

Spatial Distributions of Legacy Contaminants in Sediments of Lakes Huron and Superior

The sediments of Lake Superior, Lake Huron, and Georgian Bay were sampled in 2001 and 2002 in order to evaluate the extent of surficial sediment contamination of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), polycyclic aromatic hydrocarbons (PAHs), and metals. Sediment concentrations of PCBs, OCs, PAHs, and mercury were generally low and up to 2 orders of magnitude less than in Lakes Erie and Ontario. In contrast, concentrations of metals such as arsenic, copper, and nickel were comparable to those in Lakes Erie and Ontario. These elevated Lakes Superior and Huron metal concentrations were attributed to naturally occurring metals within the bedrock, soil, and sediment of the study region. Concentrations of all contaminants were typically below the Canadian Sediment Quality Probable Effect Level (PEL) guidelines. With regard to spatial patterns, most contaminants were focused primarily in the depositional basins and atmospheric deposition was likely the major source of these chemicals to the lakes. The major exception was for metals (not including mercury) whose patterns were also influenced by natural sources as well as extensive mining activity. A comparison between surficial sediment contamination of samples collected as part of this survey and those collected in the late 1960s/early 1970s using similar methods showed that concentrations of DDT, PCB, lead, and mercury were generally similar between these two time periods. These results are not consistent with production and usage patterns that have declined substantially in the past 3 decades. We hypothesize that the lack of temporal trends is an artifact due to slow sediment accumulation rates as well as differences in analytical protocols between the two time periods.     

Field and Laboratory Studies of Environmental Carcinogenesis in Niagara River Fish

Combined field and laboratory studies were carried out to assess the possible role of contaminated bottom sediments to neoplastic disease in fish from eastern Lake Erie and the upper Niagara River. Correlations between sediment polycyclic hydrocarbons, neoplasms in feral fish, and the induction of neoplasms in bullheads (Ictalurus nebulosus) by exposure to extracts of polluted sediment support the hypothesis that some fish neoplasms result from exposure to carcinogenic chemicals present in the fishes environment.     

The Fate of Pentachlorophenol in the Bay of Quinte,Lake Ontario

Unfiltered water, surface film, sediment, and biota samples were collected from the Bay of Quinte between May and September 1978 and analyzed for chlorophenols (CPs). Sectioned sediment cores were dated using ²¹⁰Pb and ¹³⁷Cs analyses. Pentachlorophenol (PCP) was found at high concentrations adjacent to a point source and was detected in all compartments examined throughout the bay (a bioaccumulation factor of 10⁴ was observed for PCP in fish). The ratio of 2,3,4,6- and 2,3,5,6-tetrachlorophenols (TTCPs) to PCP increased with distance from the source in the water column and surface film. Photochemical reduction was proposed to account for the phenomenon. CP concentrations in sectioned cores suggested that settling particles adsorb CPs in similar proportion to that observed in the water column and little further change occurs after burial.     

Baseline assessment of metals and hydrocarbons in the sediments of Lake Mulwala, Australia

An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg⁻¹) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons.     

Distribution of Contaminants in Clams and Sediments from the Huron-Erie Corridor. I–PCBs and Octachlorostyrene

Samples of surficial sediments and the clam species Lampsilis radiata siliquoidea were collected from 102 sites covering all of Lake St. Clair and the Canadian shoreline of the St. Clair and Detroit rivers. The distribution patterns of both octachlorostyrene (OCS) and PCBs were mapped throughout this area. The mean level of PCBs in sediments of 3.9 μg kg^?1 (Aroclor 1254) was much lower than values for “total PCBs” reported in studies carried out in the early 1970s. This reduction does not appear to reflect a real decrease in PCB levels in the environment, but rather changes that have been made in sampling procedures and analytical techniques. Highest levels of PCBs in both sample types were found along the western shore of Lake St. Clair. Mean levels of OCS in whole clam tissue and surficial sediment (0–10 cm) were 43.0 and 5.1 μg kg^?1, respectively. The distribution pattern of OCS in the Huron-Erie corridor in both clams and sediments suggests that the primary source is in the St. Clair River. The mean chemical concentration factor was 59 for OCS, indicating considerable bioaccumulation in the biota of Huron-Erie corridor.     

Sorption of polycyclic aromatic hydrocarbons into liposomes (artificial cell membranes) and the effects of dissolved natural organic matter

Dissolved natural organic matter (NOM) occurs widely in the aquatic environment and affects the fate of microorganic pollutants (e.g. intake, accumulation, movement, degradation, toxicity). The effect of NOM on the intake into biota (living cells) is very important. In the present study, the effects of coexisting NOM on the intake of microorganic pollutants into aquatic biota were experimentally evaluated. The NOM was concentrated from Lake Biwa water using a reverse osmosis filtration membrane. Two polycyclic aromatic hydrocarbons (PAH; pyrene and phenanthrene) were used as representative microorganic pollutants. Liposomes were synthesized in the laboratory to simulate living cell membranes and were used to investigate the intake of microorganic pollutants into aquatic biota. The experimental results (PAH onto NOM, NOM into liposomes, and PAH into liposomes) indicated that the sorption of PAH into liposomes was suppressed, apparently by PAH binding with NOM in the aqueous phase. This suggests that the accumulation and/or toxicity of microorganic pollutants can be retarded by NOM in the aqueous environment. Moreover, the experimental results indicated that sorption into liposomes (the liposome/water sorption coefficient, K_lipw) could be a better parameter for estimating the intake of microorganic pollutants into aquatic biota than the n-octanol/water partition coefficient (K_ow) in the aqueous environment.     

Simulation of internal nitrogen release from bottom sediments in an urban lake using a nitrog

Nutrient release from sediment is considered a significant source for overlying water. Given that nutrient release mechanisms in sediment are complex and difficult to simulate, traditional approaches commonly use assigned parameter values to simulate these processes. In this study, a nitrogen flux model was developed and coupled with the water quality model of an urban lake. After parameter sensitivity analyses and model calibration and validation, this model was used to simulate nitrogen exchange at the sedimentewater interface in eight scenarios. The results showed that sediment acted as a buffer in the sedimentewater system. It could store or release nitrogen at any time, regulate the distribution of nitrogen between sediment and the water column, and provide algae with nitrogen. The most effective way to reduce nitrogen levels in urban lakes within a short time is to reduce external nitrogen loadings. However, sediment release might continue to contribute to the water column until a new balance is achieved. Therefore, effective measures for reducing sediment nitrogen should be developed as supplementary measures. Furthermore, model parameter sensitivity should be individually examined for different research subjects.     

白马湖退圩还湖方案及效果浅析

根据白马湖圈圩现状和退圩还湖规划标准、目标、建设规模,提出白马湖退圩还湖4个方案,通过各方案水位—库容曲线、入湖流量过程设计、出湖流量过程计算,并进行调洪演算,分析不同方案的防洪滞涝效果,提出了淮安市白马湖近期退圩还湖建议实施方案。     

Comparative spatial metal concentrations and partitioning in bottom sediments of two tropical freshwater lake basins,Kenya

Metal concentrations in the water, sediments and biota in alkaline, near neutral water tropical freshwater lake basins were determined and a comparative analysis made on the spatial and accumulated trace metal concentrations, and geochemical partitioning of iron (Fe), manganese (Mn), copper (Cu), chromium (Cr), zinc (Zn), nickel (Ni), cadmium (Cd) and lead (Pb) in bottom lake sediments. Variable accumulated levels were found in the analysed sediments and aquatic biological tissues. Metal partitioning data in the present study from the two areas exhibits similar trends in magnitude. The residual fractions retained relatively higher amounts of metals. Relatively higher contents of Pb, Cr and Cu were found in Lake Victoria sediments. Cd, Ni, Mn and Pb are of concern because a higher percentage of these metals were retained in the more bioavailable fractions in Lake Naivasha. Total levels of sediment mercury were comparable for the two lake basins. Metals were found in significant levels in the tissues of aquatic organisms, highlighting the potential risks to other levels within the aquatic food chain. Although the exposure risk was not evaluated, it is important to continue monitoring these elements in fish, as sediments were found to contain considerable quantities of the metals. Numerous sediment extraction techniques data applied for evaluating metal partitioning in sediments cannot be compared because of the use of different methods. Nevertheless, the information is still useful in differentiating and understanding pollution loads from natural versus anthropogenic sources and their associated risks.     

Nutrient concentrations in the surface sediments of Lake Chivero,Zimbabwe: A shallow,hypereutrophic, subtropical artificial lake

A lake‐wide survey in Lake Chivero, Zimbabwe, was performed to (i) examine the spatial distribution of three sediment grain sizes; (ii) determine their nutrient concentrations; and (iii) analyse the relationships between the measured surface sediment variables in the three sediment grain sizes. The results of this study indicated sand, silt and mud sediments occupied about 24, 22 and 54%, respectively, of the lake area. All the measured physicochemical variables varied significantly among the three sediment grain sizes (P < 0.05, anova ). High values for pH, dissolved oxygen and NO₃ were observed in the sand sediments, while water depth, electrical conductivity, soluble reactive phosphorus, NH₄, total phosphorus, total nitrogen and total organic carbon were observed in the mud sediments. In the silt sediments, most measured variables showed intermediate values. Intervariable correlation indicated varied correlation patterns among the three sediment grain sizes. Information generated in this study is essential for an accurate delineation of the spatial extent of nutrient and contaminant distribution in the sediment of Lake Chivero and will facilitate the ability of lake managers to derive a comprehensive nutrient budget of the lake as a means of establishing realistic target conditions for lake restoration.     

Recruitment of Heliozoa, rhizopods and rotifers from the sediments of an extremely acidic lake during spring and early summer

The goal of this study was to investigate the recruitment of zooplankton from the littoral sediment of Lake 111, an acidic lake in north‐east Germany, in April (spring) and June (early summer), and its role in coupling the benthos and the pelagic. Maximum heliozoan and rhizopod recruitment occurred in early summer from sediment cores incubated at ambient water temperatures (20°C). Conversely, recruitment of the rotifer Cephalodella sp. was highest in spring at ambient spring temperatures of 12°C. A combination of passive and active recruitment processes is likely responsible. The seasonal abiotic and biotic sediment characteristics were relatively constant and therefore not likely responsible for the observed temporal recruitment pattern. The sediment water and carbon content ranged from 20 to 50% (mean = 29 ± 6% standard deviation) and 2–12% (mean = 5 ± 2% standard deviation), respectively. Similarly, there was little variation in the chlorophyll‐a (mean = 0.2 ± 0.2 µg Chl‐a g^?1 dry weight ≡ 6.1 ± 3.9 mg Chl‐a m^?2). The in situ sediment bacterial density (0.82 × 10⁹ ± 0.26 × 10⁹ g^?1 dry weight ≡ 1.01 × 10⁹ ± 0.34 × 10⁹ cells cm^?3) was high. In contrast, the abundance of zoobenthos and their resting stages was low (< 25 individuals cm^?3, and mean of 90 ± 75 cysts cm^?3, respectively), with no temporal pattern being observed. Temperature was the only abiotic factor influencing recruitment. This study suggests that, even in relatively young, chemically extreme lakes, the benthos can play an important role in whole lake microbial processes and zooplankton community composition. Such benthic repositories of resting stages potentially provide protection against adverse environmental changes.     

北京市北运河流域河水和地下水多环芳烃分布规律及风险评价

为研究北运河流域河水与不同含水层地下水体中多环芳烃(PAHs)的相互作用,收集北运河流域上游温榆河段及下游北运河段不同季节的河水与地下水水质数据,采用对比分析及显著性分析方法研究河水与地下水中多环芳烃的组成、含量及时空分布特征,并利用风险熵法进行风险评价。结果表明:16种优控多环芳烃中,除苯并[a]芘和二苯并[a,h]蒽检出率不足100%外,其余14中多环芳烃污染物在河水、潜水和承压水中均全部检出;多环芳烃总质量浓度的构成以萘为主,质量浓度为1 587.42ng/L,约占总质量浓度的85.6%;潜水和承压水春季多环芳烃总质量浓度显著低于夏季,2～3环多环芳烃质量浓度高于4环以上多环芳烃质量浓度;潜水中多环芳烃总质量浓度高于承压水;北运河段潜水中多环芳烃总质量浓度高于温榆河段;温榆河段地下水主要污染物为萘、芴和菲,北运河段地下水主要污染物为萘、苊和菲;上游河水多环芳烃总质量浓度低于下游,主要污染物为萘和菲;萘、芴、菲、蒽、荧蒽、芘、苯并[a]蒽在不同位置条件下差异显著,除苯并[a]蒽、苯并[b]荧蒽、苯并[a]芘和二苯并[a,h]蒽之外,其余多环芳烃在不同季节条件下均差异显著;通过风险熵法计算得出不同季节和位置条件下研究区生态风险相对较低。     

太湖流域水源地多环芳烃分布、溯源与生态风险评估

利用GC-MS对太湖流域水源地多环芳烃(PAHs)的浓度水平进行监测分析。结果表明,3月水相、悬浮颗粒物和沉积物中PAHs的质量浓度分别为63.5~393.9 ng/L、167~4 358.2 ng/g和940.8~7 398.3 ng/g,分别远高于6月的21.1~64.6 ng/L、125.6~282.3 ng/g和337.3~1 318 ng/g。不同月份单体PAH浓度水平差异较大,可能受控于污染物来源、径流稀释和水动力条件的差异性。特征比值判源结果表明,6月水相和悬浮颗粒物中PAHs主要来源于石油类泄漏和燃烧过程,而沉积物中PAHs在3月和6月均体现为混合源。生态风险评估结果表明,水相、悬浮颗粒物和沉积物中PAHs的生态风险较小,但个别样点单体PAH的含量高于基于生物影响试验的风险评价低值ER-L和ISQV-L,说明存在一定的健康风险,需引起重视。     

排入湖泊的含沙水流三维运动特性研究

本文采用拉格朗日法，考虑泥沙颗粒水体的托曳力，浮力、压差力和附加质量力的合力作用，并用随机方法计入流体紊动的影响，建立颗粒随机运动轨迹方程。采用三维k-ε模型模拟流场。本文以一抽水蓄能电站为例，预测了在抽水情况下排入上池湖泊中的五个粒径组的泥沙在不同时刻的运动轨迹、速度及在三维空间上的体积浓度分布，预测了各种粒 径沙粒可能沉降的位置。     

长江中游岸线水域典型污染物种类与来源解析

以长江中游宜昌段、武汉段和黄石段3个监测断面为研究对象,选取农业渔业、工业生产、港口物流、过江交通和城镇生活共5种典型开发类型岸线,鉴别了不同开发类型岸线水域主要污染物种类,同时解析了其时空分布状况.结果 表明,依据《地表水环境质量标准》(GB 3838-2002)和《生活饮用水卫生标准》(GB 5749-2006),...