九龙江口滨海湿地生源要素空间分布特征

为了揭示亚热带典型滨海湿地生源要素的空间分布特征及影响因素,选取九龙江口滨海湿地为研究对象,于2009年夏采集表层沉积物及柱状样,利用元素分析仪和流动注射分析仪对主要生源要素碳、氮、磷、硫(C、N、P、S)进行分析.结果表明,九龙江口滨海湿地生源要素含量较高,总碳、总氮、总磷、总硫(TC、TN、TP、TS)的均值分别为(12.64±2.66)、(1.57±0.29)、(0.48±0.06)、(2.61±1.37)g·kg-1,空间分布差异性显著.红树林植被区表层沉积物的TC、TN、TP含量高于米草植被及光滩,高潮位TC、TN、TP含量>中潮位>低潮位,TS在米草植被及中潮位含量较高.柱状样的TC、TN具有相似的垂直变化趋势,均表现为由表层向下逐渐降低,且不同植被间的柱状样TC、TN含量在同一深度上都表现为:红树区>米草区>光滩区;柱状样TP平均值是光滩最低,TS平均值是光滩最高.冗余分析表明,植被类型、pH及潮位是影响表层沉积物生源要素(C、N、P、S)分布最显著的环境因子,解释量分别为24.0%、19.0%和11.6%.     

Speciation of organic phosphorus in a sediment profile of Lake Taihu II. Molecular species and their depth attenuation

The understanding of organic phosphorus(P) dynamics in sediments requires information on their species at the molecular level,but such information in sediment profiles is scarce.A sediment profile was selected from a large eutrophic lake,Lake Taihu(China),and organic P species in the sediments were detected using solution phosphorus-31 nuclear magnetic resonance spectroscopy(31 P NMR) following extraction of the sediments with a mixture of 0.25 mol/L NaOH and 50 mmol/L EDTA(NaOH-EDTA) solution.The results showed that P in the NaOH-EDTA extracts was mainly composed of orthophosphate,orthophosphate monoesters,phospholipids,DNA,and pyrophosphate.Concentrations of the major organic P compound groups and pyrophosphate showed a decreasing trend with the increase of depth.Their half-life times varied from 3 to 27 years,following the order of orthophosphate monoesters > phospholipids DNA > pyrophosphate.Principal component analysis revealed that the detected organic P species had binding phases similar to those of humic acid-associated organic P(NaOH-NRP HA),a labile organic P pool that tends to transform to recalcitrant organic P pools as the early diagenetic processes proceed.This demonstrated that the depth attenuation of the organic P species could be partly attributed to their increasing immobilization by the sediment solids,while their degradation rates should be significantly lower than what were suggested in previous studies.     

化学铁盐辅助除磷对生物除磷的影响研究

化学辅助除磷有助于污水厂实现磷达标,但其对生物系统存在潜在的影响。针对除磷药剂对生物除磷过程的影响展开研究,选用硫酸亚铁进行化学辅助除磷。药剂形成的化学污泥干扰生物除磷过程且成分复杂,故以磷酸铁、氢氧化铁模拟化学污泥,由钾离子、K/P摩尔比计算出同步除磷中的生物除磷,来探讨化学污泥对聚磷菌释磷/吸磷过程的影响。结果表明,连续投加硫酸亚铁使聚磷菌的释磷量、吸磷量降低;系统中磷酸铁含量0.075 mmol/L时聚磷菌的释磷和吸磷能力提高了约25%,磷酸铁含量0.15 mmol/L时对聚磷菌吸磷有抑制作用;氢氧化铁对聚磷菌释磷、好氧初期吸磷均有抑制作用。生物污泥与化学污泥存在交互作用。     

水中脲类除草剂Chlortoluron氯化产物鉴定、降解途径探究

对不同pH下Chlortoluron氯化后生成的非挥发性中间产物和挥发性产物进行了研究。对Chlortoluron氯化后的非挥发性中间产物的UPLC-ESI-MS鉴定发现了m/z为213、229、263、281、和247的离子,分析表明它们分别是Chlortoluron及其一羟基、一氯羟基、二氯和一氯衍生物。对Chlortoluron氯化后的挥发性产物采用吹扫补集-GC-MS进行分析鉴定发现了三氯甲烷(CF)、二氯硝基甲烷(DCNM)、二氯乙腈(DCAN)、1,1-2-二氯丙酮(1,1-DCP)、三氯硝基甲烷(TCNM)和1,1,1-2-三氯丙酮(1,1,1-TCP)六种消毒副产物。根据本研究中的实验结果分析和推测,在Chlortoluron的氯化过程中,苯环上和脲基链上都经历了羟基化、氧化和取代反应,接着苯环被打破,随后生成了更为有害的副产物,基于此,本文推断了Chlortoluron的氯化降解途径。     

模型模拟在城市SO2环境容量测算中的应用研究

以许昌市污染源普查数据为基础,通过现状排放、环境质量控制目标与预测环境质量、污染物削减和浓度贡献分析,核定得到了准确可靠的许昌市二氧化硫环境容量;研究建立的从宏观理想容量到实际容量的多源模型体系,能较好地应用于二氧化硫环境容量研究;A—P值法、AERMOD模型均能较好地模拟污染源与环境空气质量的响应关系,且二者具有较好的一致性,可作为可靠的多源模型广泛应用于中小城市的二氧化硫环境容量核定研究及环境规划管理。     

上海市青浦城厢地区可吸入颗粒物污染状况分析

为了研究青浦城厢地区可吸入颗粒物污染状况,分析了2005年至2010年空气质量资料,结果表明:青浦城厢地区首要污染物为PM10,其质量浓度呈逐年下降趋势。PM10浓度的月度变化幅度比较大,全年PM10浓度及超标率呈现"高一低一高"的变化趋势。春、冬季比较高,夏、秋季比较低。PM10质量浓度的日变化非常明显,呈现出"双峰"状分布。PM2.5和PM10的平均比值为0.531,表明该地区可吸人颗粒物中细颗粒物的比例较高,细颗粒物对人群的健康影响更为严重。PM10和PM2.5各月日均值之间和各月均值之间均呈高度相关,线性关系非常显著,二者之间回归直线关系存在,可用回归方程y=ax+b进行计算。     

水钠锰矿的Mn（Ⅲ）分布及Na4P2O7溶液处理对其铅吸附性能的影响

以深入理解水钠锰矿结构中低价锰离子的含量及分布对其铅吸附性能的影响为目的,通过不同pH（pH为2、4、5）的焦磷酸钠溶液络合浸提酸性水钠锰矿结构中的Mn（Ⅱ）和Mn（Ⅲ）,研究了浸提锰离子的形态、含量、矿物的锰平均氧化度和Pb2＋的吸附量及其伴随Mn2＋、H＋释放量的变化.结果表明,锰平均氧化度为3.670的酸性水钠锰...     

焦化行业苯并芘排放量与厂界达标预测分析

论文以某100万吨/年焦化项目为例,分析其在不同地形和风速参数条件下苯并芘排放量,预测不同条件下距离焦炉炉体中心-1000～1000米范围内各网格点的苯并芘超标概率,最终得出风速、地形参数对苯并芘浓度超标概率的影响.     

城镇污水处理厂脱氮除磷好氧污泥颗粒化研究

采用序批式生物反应器(SBR)培养好氧颗粒污泥处理模拟废水,优化好氧颗粒污泥内部好氧-兼氧-厌氧微环境,在反应器的快速启动、稳定运行阶段分别考察不同优化条件下系统的脱氮除磷性能。提出了优化污泥沉降时间、调控曝气方式等好氧污泥快速颗粒化途径,并研究排泥方式对颗粒污泥反应器稳定性的影响,通过强化脱氮除磷功能菌富集,实现氮磷同步高效去除。     

A survey of antennal responses by five species of coniferophagous bark beetles (Coleoptera: Scolytidae) to bark volatiles of six species of angiosperm trees

Summary. Using Porapak Q traps, we collected the bark volatiles of six angiosperm trees native to British Columbia: black cottonwood, Populus trichocarpa Torr. & A. Gray (Salicaceae), trembling aspen, P. tremuloides Michx. (Salicaceae), paper birch, Betula papyrifera Marsh. (Betulaceae), bigleaf maple, Acer macrophyllum Pursh (Aceraceae), red alder, Alnus rubra Bong. (Betulaceae), and Sitka alder, A. viridis ssp. sinuata (Regel) á. L?ve & D. L?ve (Betulaceae). Utilising coupled gas chromatographic-electroantennographic detection analysis, the captured volatiles were assayed for antennal responses in five species of coniferophagous bark beetles (Coleoptera: Scolytidae), sympatric with most or all of the angiosperm trees: the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, the mountain pine beetle, D. ponderosae Hopkins, the spruce beetle, D. rufipennis (Kirby), the western balsam bark beetle, Dryocoetes confusus Swaine, and the pine engraver, Ips pini (Say). The identities of 25 antennally-active compounds were determined by coupled gas chromatographic-mass spectroscopic analysis, and co-chromatographic comparisons with authentic chemicals. The compounds identified were: hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 1-hexanol, heptanal, α-pinene, frontalin, benzaldehyde, β-pinene, 2-hydroxycyclohexanone, 3-carene, limonene, β-phellandrene, benzyl alcohol, (E)-ocimene, salicylaldehyde, conophthorin, guaiacol, nonanal, methyl salicylate, 4-allylanisole, decanal, thymol methyl ether, (E)-nerolidol, and dendrolasin. A number of these compounds are known semiochemicals that are active in the behaviour of other organisms, including bark beetles, suggesting a high degree of semiochemical parsimony. Antennally-active compounds ranged from seven in A. viridis to 17 in P. trichocarpa. The fewest number of compounds (9) were detected by I. pini and the largest number (24) were detected by D. pseudotsugae. Six compounds excited the antennae of all five species of bark beetles. The large number of antennally-active compounds detected in common by numerous bark beetles and present in common in numerous nonhost trees supports the hypothesis of olfaction-based recognition and avoidance of nonhost angiosperm trees during the process of host selection by coniferophagous bark beetles. Received 13 December 1999; accepted 14 March 2000