八面河低成熟油生物标志化合物碳同位素分析和研究

利用化学预处理与气相色谱—同位素质谱相结合的分析手段，在国内首次完成了原油中甾花生物标志化合物的联同位素鉴定。选择我国济阳拗陷八面河油田典型低成熟油作为样品，对其昌萜生物标志化合物的碳同位素的特征进行了初步探讨。     

Effect of a seasonal di use pollution migration on natural organic matter behavior in a stratified dam reservoir

This article aims to describe the influence of di use pollution on the temporal and spatial characteristics of natural organic matter (NOM) in a stratified dam reservoir, the Daecheong Dam, on the basis of intensive observation results and the dynamic water quality simulation using CE-QUAL-W2. Turbidity is regarded as a comprehensive representation of allochothonous organic matter from di use sources in storm season because the turbidity concentration showed reasonable significance in a statistical correlation with the UV absorbance at 254 nm and total phosphorus. CE-QUAL-W2 simulation results showed good consistency with the observed data in terms of dissolved organic matter (DOM) including refractory dissolved organic carbon (RDOC) and labile DOC and also well explained the internal movement of constituents and stratification phenomenon in the reservoir. Instead turbidity and NOM were related well in the upper region of the reservoir according to flow distance, gradually as changing to dissolved form of organic matter, RDOM a ected organic matter concentration of reservoir water quality compared to turbidity. To control the increase of soluble organic matters in the dam reservoir, appropriate dam water discharge gate operation provided e ective measurement. Because of the gate operation let avoid the accumulation of organic matter within a dam reservoir by shorten of turbid regime retention time.     

石墨电热消解-重铬酸钾法测定沉积物的有机质

用石墨高温电热消解仪替代以往的油（砂）浴,消解测定沉积物的有机质,具有消解温度稳定,各部位加热均匀的特点,克服了油（砂）浴存在的安全卫生差和温度控制难的问题。加之自制和使用了不舍有机物的接近实际样品的空白样,使空白值和实际测定结果更具可信性。从而,测定实际有机质样品的精密度较好（Rsd=2．1％）,测定海洋环境监测沉积物外控样的成绩优秀（测定值与后来公布的平均值吻合）,方法的扩展不确定度仅为1．9％。     

兰州市排污沟淤泥的有机质特征及来源分析

文章对兰州市西部工业区、生活区、医院等功能区的排污沟上、中、下段淤泥中饱和烃组成与分布特征进行了分析,初步认识了饱和烃的来源和组成特征。分析表明,排污沟淤泥中分布多种类型的饱和烃化合物,主要包括正构烷烃、无环类异戊二烯烷烃、萜类化合物、甾烷等。正构烷烃组成特征均为双峰态后峰型,主峰碳数为C15-C18和C25-C31。样品中检测出27种萜类化合物,其中五环萜类较三环萜类化合物占优势。甾烷化合物主要包括规则甾烷、重排甾烷、孕甾烷,以规则甾烷为主。有机质生物标志物参数表明,排污沟淤泥中有机质具有成熟和不成熟的特征,主要为现生植物、矿物油和化石燃料对烃类化合物的贡献,并且在不同区段由于外源有机物的加入而表现不同,有机质为多源混合来源。人类活动较集中的中段受矿物油和化石燃料燃烧污染程度明显比上游和下游严重。     

Effects of free iron oxyhydrates and soil organic matter on copper sorption-desorption behavior by size fractions of aggregates from two paddy soils

Effects of free iron oxyhydrates (Fed) and soil organic matter (SOM) on copper (Cu2+) sorption-desorption behavior by size fractions of aggregates from two typical paddy soils (Ferric-Accumulic Stagnic Anthrosol (Soil H) and Gleyic Stagnic Anthrosol (Soil W)) were investigated with and without treatment of dithionite-citrate-bicarbonate and of H2O2. The size fractions of aggregates were obtained from the undisturbed bulk topsoil using a low energy ultrasonic dispersion procedure. Experiments of equilibrium sorption and subsequent desorption were conducted at soil water ratio of 1:20, 25℃. For Soil H, Cu2+ sorption capacity of the DCB-treated size fractions was decreased by 5.9% for fine sand fraction, by 40.4% for coarse sand fraction, in comparison to 2.9% for the bulk sample. However, Cu2+ sorption capacities of the H2O2-treated fractions were decreased by over 80% for the coarse sand fraction and by 15% for the clay-sized fraction in comparison to 88% for bulk soil. For Soil W, Cu2+ sorption capacity of the DCB-treated size fraction was decreased by 30% for the coarse sand fraction and by over 75% for silt sand fraction in comparison to 44.5% for the bulk sample. Cu2+ sorption capacities of the H2O2-treated fractions were decreased by only 2.0% for the coarse sand fraction and by 15% for the fine sand fraction in comparison to by 3.4% for bulk soil. However, Cu2+ desorption rates were increased much in H2O2-treated samples by over 80% except the clay-sized fraction (only 9.5%) for Soil H. While removal of SOM with H2O2 tendend to increase desorption rate, DCB- and H2O2-treatments caused decrease in Cu2+ retention capacity of size fractions. Particularly, there hardly remained Cu2+ retention capacity by size fractions from Soil H after H2O2 treatment except for clay-sized fraction. These findings supported again the dominance of the coarse sand fraction in sorption of metals and the preference of absorbed metals bound to SOM in differently stabilized status among the size fractions. Thus, enrichment and turnover of SOM in paddy soils may have great effects on metal retention and chemical mobility in paddy soils.     

边缘海环境中陆源有机质的化学生物标志物研究进展

边缘海是陆地和大洋的连接带,是陆源物质向开阔海输送的主要途径,在全球碳循环过程发挥着重要的作用。示踪边缘海沉积有机碳的来源,可以为有机碳的分布、降解、迁移和转化等研究提供基础。本文从高等植物类脂化合物(如长链正构烷烃、正构烷醇、脂肪酸、甾醇等)、维管植物木质素和土壤有机质支链和类异戊二烯四醚(BIT)等几个方面,介绍了基于化学生物标志物示踪边缘海陆源有机质来源的研究进展。指出以包含木质素、BIT等指标在内的多重示踪方法和多端元模型是指示边缘海沉积有机质来源的良好方法,能够提供比单指标方法更为准确可靠的结果。     

土壤中不同有机质对菲的吸附行为及生物可利用性的影响

为了研究不同有机质对持久性有机污染物(POPs)的吸附行为及生物可利用性的影响,从黑龙江省未被多环芳烃(PAHs)污染的农业表层土壤中提取了矿质结合态胡敏酸(MHA)、矿质结合态胡敏素(MHU),通过绘制吸附动力学曲线和吸附等温线,研究了MHA、MHU及全上本身对菲的吸附特性,并通过改变老化时间和吸附剂质量,研究了不同...     

生态系统转换区土壤有机质动力学特征的δ^13C方法研究

对土壤有机质的动力学过程的研究是评价区域土壤质量、合理开发利用土壤以及全球碳循环一气候交化研究的基础性工作。系统分析了生态系统转换区土壤有机质动力学特征的δ^13C方法研究的理论基础和应用现状,包括影响土壤有机质δ^13C值的各种内外因素;土壤有机质不同化学组成、不同粒径组分、不同比重组分的δ^13C特征值域;土壤微生...     

花溪河水溶解无机碳同位素的季节变化

对乌江上游支流花溪河水进行了一年的监测,测定了DIC含量和δ13 CDIC。结果显示DIC含量在1.73～4.53mmol/L之间,δ13 CDIC的变化范围-9.6‰～-3.6‰,反映了碳酸盐岩的主要控制作用,δ13 CDIC和DIC含量之间存在负相关关系,表明有机质分解作用、生物作用对河水DIC也有着重要影响。冬季...     

金泽水库上游来水及库区水质变化时空分布特征

金泽水库是上海西南五区的主要饮用水源,上游太浦河来水及库区水质变化对水库运行和相应供水系统供水水质有重要影响.基于常规水质指标应用主成分分析法评价了不同季节金泽水库上游来水及库区水质变化;利用平行因子(PARAFAC)分析了金泽水库上游来水及库区水中荧光溶解性有机质(FDOM)组成结构及分布特征;通过相关性分析分析了水体荧光强度与常规水质指标间的关系.结果表明,金泽水库上游来水及库区冬季水质最差,库外断面水质受外源污染逐步恶化,经过库区生态净化作用后水质有所提升;水体FDOM主要由类蛋白类和类腐殖质类组分构成,类蛋白物质为主要组分,各组分呈现出明显的时空分布特征,外源污染是影响库外断面FDOM总荧光强度的主要因素,生态环境是影响库内FDOM总荧光强度季节性波动的主要因素. FDOM总荧光强度呈现上游低下游高的趋势,与水中NH4+-N、石油类、TOC、氯化物和硫酸盐含量显著相关,通过检测FDOM总荧光强度可实现对水体水质的快速分析并发挥预警和指示作用.