鄱阳湖入湖、出湖污染物通量时空变化及影响因素(2008-2012年)

研究鄱阳湖入、出湖污染物通量是加强鄱阳湖及长江水功能区限制纳污红线管理的前提,是建立鄱阳湖水质预测模型的基础.基于2008-2012年鄱阳湖8条主要入湖河流、出湖口的逐月水量、水质同步监测资料,根据污染源特征优选算法,计算总磷(TP)、氨氮(NH3-N)、高锰酸盐指数(CODMn)的入、出湖污染物通量,并分析时空变化特征及影响因素.结果表明:(1)出湖口和乐安河入湖口断面的NH3-N、TP及昌江入湖口断面的TP,以点源污染为主,采用每月瞬时通量作为月平均通量的算法更准确;其余以非点源污染为主,采用瞬时污染物浓度与月平均流量之积来计算月平均通量更准确.(2)2008-2012年CODMn、NH3-N和TP年平均人湖通量分别为304398、53063和9175 t,年平均出湖通量分别为367436、45814和8452t.8条入湖河流每年的入湖水量、CODMn通量和个别年份的NH3-N、TP通量小于出湖,这主要是因为未计算区间产流及相应排污和采砂引起的内源污染.(3)入、出湖污染物通量在年际间主要受水量影响而呈现W型波动变化趋势,CODMn、NH3-N、TP入湖通量及CODMn出湖通量均集中在汛期,NH3-N、TP出湖通量则是冬季较多(低水位下湿地植被净化作用受限).入湖TP、NH3-N、CODMn通量主要来自赣江、信江、乐安河,而NH3-N、TP浓度最高的是乐安河、信江.     

Association of Humic Substances: Verification of Lambert‐Beer Law

The precision UV/Vis‐absorption spectra of a naturally occurring aquatic humic substance were measured in the range of concentration 0.003 to 1.4 g/L DOC (dissolved organic carbon). Lambert‐Beer law is well obeyed at low concentrations whereas deviations have been observed for DOC concentrations above 0.1 g/L: they are interpreted in terms of self‐solvation and formation of micelles.     

Effect of Preozonation on the Formation of Chlorinated Disinfection By‐products for River Ruhr

The purpose of the study is to gain a better understanding about the formation of THM (trihalomethanes), HAA (haloacetic acids), and AOX (adsorbable organic halogen) in river water (river Ruhr, Essen) through a chlorination kinetics approach. The effect of chlorination time and preozonation on the formation of THM, HAA, and AOX substances was studied. Preozonation can reduce the chlorine demand and the precursors for AOX and THM. THM generation was reduced further, when the ozone dosage consumed increased from 3.5 to 12.5 mg in the 1.4 L reaction vessel. AOX and TCAA (trichloroacetic acid) concentrations also decreased dramatically when 3.5 mg of ozone had reacted with the river water, but a higher dose of ozone did not further reduce AOX and TCAA formations. Besides, the characteristics of organic matter in raw water, ozonated water, and preozonated/chlorinated water was investigated. The results suggest the formation of low‐molecular‐weight acids with low UV absorbance when high‐molecular refractive matter is oxidized.     

全国行业COD和TN污染物产强环境准入基准体系研究

围绕当前中国源头治理与产业转型升级之间脱节严重的突出问题,在编制行业小类污染源全覆盖且取值简便的产强系数等级划分表的基础上,构建全国行业小类农业、工业、服务业和生活源化学耗氧量(COD)和总氮(TN)污染物产强环境准入基准体系,并以青岛市为例,评价污染源产强环境准入基准的可靠性和准确性。通过聚类分组和归并,“全国产强列表手册”编列的3022个COD和1734个TN亚小类污染源归一化产强系数都可划分为13个等级。对于“全国产强列表手册”编列的321个COD和133个TN行业小类,产强准入基准等级构成有显著差异,分别有10和12个等级,其中不同等级占比分别是II-2和IV-6最高,V-9和VI-12最低。根据产强系数检验性监测结果按从严标定准入基准表明,对于青岛市254个COD和109个TN行业小类,产强准入基准构成与全国有所不同,分别有10和11个等级,其中分别有77和14个低于全国准入基准等级。根据青岛市陆源COD和TN产污数量比较分析表明,分级比分类产强核算结果平均相差约6%,远远低于产强系数检验性监测偏差(49%)和13等级产强等级内变幅(39%)。这说明,在按“全国行业小类COD和TN污染物产强环境准入基准体系”建立完善中国污染源产强环境准入制度中,不仅按产污数量分级产强核算结果具有相当的准确性,而且按从严标定准入基准的原则也具有相当的可靠性。     

Cu2+/SnO2复合纳米光催化剂的制备及其对海洋柴油污染物的降解

采用化学沉淀法成功制备了Cu2+/SnO2复合纳米光催化剂,采用XRD、SEM等测试手段对复合纳米光催化剂的粒径、形态等进行表征。在紫外光条件下,分别改变催化剂掺杂比、催化剂煅烧温度、催化剂投加量、柴油初始含量和光照时间等单因素,探究不同条件对Cu2+/SnO2复合纳米光催化剂降解海洋柴油污染物的影响。结果表明,自制复合纳米光催化剂可以有效降解海水中的柴油污染物,在紫外光作用下,于400℃下煅烧Cu/Sn掺杂比为0. 03的Cu2+/SnO2复合纳米光催化剂、投加量为0. 2 g/dm3、柴油初始含量为0. 15 g/dm3、H2O2溶液含量为0. 2 g/dm3、溶液的p H为7、光照时间3 h时效果最好,海水中柴油的去除率最高,达到86. 98%。Cu2+/SnO2复合纳米光催化剂用聚丙烯纳米球负载后可以实际应用于海洋中,便于回收。     

春、秋季考洲洋海水质量状况及评价方法初探

文章利用2017年11月（秋季）和2018年4月（春季）对惠州考洲洋海域开展的两个航次水环境调查数据,分析了考洲洋海域表层溶解氧（DO）、化学需氧量(COD)、无机氮(DIN)、无机磷(DIP)和石油类（OIL）等典型水质因子的水平分布和季节变化情况。结果表明,秋季溶解氧、化学需氧量、石油类分别在盐洲岛以东附近海域、考洲洋湾顶海域和盐洲岛东南海域出现高值区,而无机氮在整个考洲洋无明显区域分布差异,无机磷含量呈现考洲洋内湾到湾口逐渐递减的趋势;春季化学需氧量、无机磷均在考洲洋湾顶出现高值区域,无机氮在盐洲岛以东附近海域出现高值区,而溶解氧和石油类无明显变化。从季节变化来看,秋季考洲洋海域溶解氧、化学需氧量和石油类平均含量均比春季高;无机氮、无机磷则相反,平均含量秋季低于春季。同时,文章还分别利用单因子和综合因子方法对海水有机污染状况进行评价并对其进行比较分析,结果表明,有机污染评价指数法可充分考虑多种水质因子,更适合对考洲洋水环境质量进行评价,得到较为客观的综合评价结果。     

Organic matter characterisation and turnover in the sediment and seawater of a tourist harbour

A survey of a Ligurian tourist harbour was carried out during winter 2006 and summer 2007 in order to study the organic matter (OM) turnover through extracellular enzymatic activity. Seawater and sediments were sampled at six stations, three inside the port boundaries, one outside the port and two in an area influenced by the outflow of a minor river (Boate). The seawater showed OM turnover times similar to other oligo-mesotrophic coastal areas, and low concentrations of chlorophyll-a and inorganic nutrients. The sediments, instead, revealed high OM loads and a predominance of proteolysis. A significant reduction of the OM loads was observed in the outside station, indicating that the OM accumulation was due to the structures and activities of the harbour and to the Boate influence. The OM biotic recycling via enzymatic activity was enhanced especially during summer. Although the carbohydrates were probably highly refractory, their turnover was notably faster, due to glycolytic enzymatic activity that was enhanced more than the proteolytic in both the sediment and in the seawater. This suggested that the removal and recycling of OM were potentially efficient, and prevented the shift to eutrophication of the Rapallo harbour area.     

Depositional environment and hydrocarbon source potential of the Oligocene Ruslar Formation (Kamchia Depression; Western Black Sea)

The Oligocene Ruslar Formation is a hydrocarbon source rock in the Kamchia Depression, located in the Western Black Sea area. Depositional environment and source potential of the predominantly pelitic rocks were investigated using core and cuttings samples from four offshore wells. In these wells the Ruslar Formation is up to 500 m thick. Based on lithology and well logs, the Ruslar Formation is subdivided from base to top into units I–VI. Dysoxic to anoxic conditions and mesohaline to euhaline salinities prevailed during deposition of the Ruslar Formation. Relatively high oxygen contents occurred during early Solenovian times (lower part of unit II), when brackish surface water favoured nannoplankton blooms and the deposition of bright marls (“Solenovian event”). Anoxic conditions with photic zone anoxia were established during late Oligocene times (units III and IV) and, probably, reflect a basin-wide anoxic event in the Eastern Paratethys during Kalmykian times. Organic carbon content in the Ruslar Formation is up to 3%. Autochthonous aquatic and allochthonous terrigenous biomass contribute to the organic matter. Relatively high amounts of aquatic organic matter occur in the lower part of the Ruslar Formation (units I and II) and in its upper part (unit VI). Diatoms are especially abundant in the lower part of unit VI. The kerogen is of type III and II with HI values ranging from 50 to 400 mgHC/gTOC. Units I and II (Pshekian, lower Solenovian) are characterized by a fair (to good) potential to produce gas and oil, but potential sources for gas and oil also occur in the Upper Oligocene units IV–VI.     

Origins and maturity of organic matter in mid-Cretaceous black shales from ODP Site 1138 on the Kerguelen Plateau

We have conducted elemental, isotopic, and Rock-Eval analyses of Cenomanian–Santonian sediment samples from ODP Site 1138 in the southern Indian Ocean to assess the origin and thermal maturity of organic matter in mid-Cretaceous black shales found at this high-latitude location. Total organic carbon (TOC) concentrations range between 1 and 20 wt% in black to medium-gray sediments deposited around the Cenomanian–Turonian boundary. Results of Rock-Eval pyrolysis indicate that the organic matter is algal Type II material that has experienced modest alteration. Important contributions of nitrogen-fixing bacteria to the amplified production of organic matter implied by the high TOC concentrations is recorded in δ¹⁵N values between −5 and 1‰, and the existence of a near-surface intensified oxygen minimum zone that favored organic carbon preservation is implied by TOC/TN ratios between 20 and 40. In contrast to the marine nature of the organic matter in the Cenomanian–Turonian boundary section, deeper sediments at Site 1138 contain evidence of contributions land-derived organic matter that implies the former presence of forests on the Kerguelen Plateau until the earliest Cenomanian.     

Distributions and sources of bulk organic matter and aliphatic hydrocarbons in surface sediments of the Bohai Sea, China

Surface sediment samples from a matrix of fifty-five sites covering virtually the entire Bohai Sea (Bohai), China were analyzed for total organic carbon (TOC), total nitrogen (TN), n-alkanes, unresolved complex mixture (UCM), biomarkers and stable carbon isotopic composition (δ¹³C), and principal component analysis was performed for source identification of organic matter (OM). The distribution of organic carbon correlated well with sediment grain size with the finest sediments having the highest concentration, suggesting the influence of hydrodynamics on the accumulation of sedimentary organic matter (SOM). The corrected TOC/ON (organic nitrogen) ratios and δ¹³C indicated mixed marine and terrestrial sources of SOM. Results suggested that δ¹³C could be used as a potential indicator to observe the dispersion of Huanghe-derived sediments in Bohai. Total n-alkane concentrations varied over 10-fold from 0.39 to 4.94 μg g^− 1 (dry weight) with the maximum terrigenous/aquatic alkane ratio observed at the Huanghe River Estuary (HRE) due to more higher plant OM from riverine inputs. C₁₂–C₂₂ n-alkanes with even-to-odd predominance were observed in several central-eastern Bohai sites. The HRE and its adjacent area is the main sink for the Huanghe river-derived OC. The ubiquitous presence of UCM, biomarkers (hopanes and steranes) and PCA results indicated the presence of petroleum contamination in Bohai, mainly from offshore oil exploration, discharge of pollutants from rivers, shipping activities and atmospheric deposition.