上海市典型城市河岸带不同植被类型下土壤反硝化作用研究

为了解城市河岸带不同植被类型下土壤的反硝化速率及其影响因子,在上海市城市河岸带的长风绿地选择了熊掌木、硕苞蔷薇和矮生百慕大草3种植被类型,于2012年3月（春初）、5月（春季）、7月（夏季）、11月（秋季）测定了其下不同深度（2～5 cm、12～15 cm、22～25 cm和32～35 cm）土壤的反硝化速率和土壤的粒度、含水率、SOC、NH4+和NO3-含量等基本理化性质。结果表明:长风绿地3种植被类型下土壤理化性质和反硝化速率具有一定的差异性,但均表现为2～5 cm深度土壤反硝化速率显著高于其他深度;熊掌木和硕苞蔷薇2~5 cm深度土壤反硝化速率均为春初显著高于其他季节,而草地2~5 cm深度反硝化速率在春夏季显著高于春初和秋季;其他深度土壤均不存在显著的季节性差异;植被类型、深度和季节对反硝化速率的单一和综合影响效应（除植被类型*深度外）均显著;反硝化速率与土壤的SOC、NH4+和NO3-含量呈极显著正相关（p<001）,而与土壤含水率和气温没有显著相关关系     

Algae mediate submerged macrophyte response to nutrient and dissolved inorganic carbon loading: A mesocosm study on different species

Nutrient and dissolved inorganic carbon are two important factors that influence the development and species composition of submerged macrophyte communities in shallow lake ecosystems. Yet little is known about their potential interactive effects on the submerged macrophytes and competition outcome of macrophyte–phytoplankton. We performed a mesocosm experiment to investigate the growth and photosynthetic performance of three submerged macrophytes in relation to phytoplankton/epiphyton with nutrient and bicarbonate enrichment. During the experimental period (42 d), increase in nutrient loading in water column resulted in a substantial burst of phytoplankton and epiphyton growth and increased light attenuation. When combined with nutrient loading, bicarbonate enrichment also resulted in a heavily phytoplankton- and epiphyton-dominated state, although bicarbonate enrichment per se does not cause the phytoplankton and epiphyton growth. However, increase in nutrient loading in water column had significant negative impact on individual performances (growth and photosynthesis) of the three submerged macrophytes and bicarbonate enrichment increased the effect of eutrophication on two dissected-leaf macrophytes (M. spicatum and E. nuttallii). Furthermore, our results also suggest that species-specific photosynthetic performances occurred when submerged macrophytes in an environment with high abundance of phytoplankton/epiphyton. This study highlighted that increase in nutrient loading and bicarbonate in water column is likely to interactively impact both abiotic and biotic properties of a freshwater ecosystem. The interactions of these two factors could select macrophyte species that are able to resist the shading from phytoplankton/epiphyton, making these species more dominant in natural freshwater ecosystems.     

柴油发电机房噪声治理的优化设计及应用

目前柴油发电机房噪声的设计与治理方法没有形成固定的模式,为了解决这个问题,文章以某柴油发电机房噪声治理为例,对该噪声控制进行理论探讨、设计计算和技术优化。以此为据完成了工程,取得了良好的处理效果。并为柴油发电机房噪声控制提供了一种可供参考的方法。     

肥料配施对土壤蓄水抗旱性能的影响

田间和室内施肥实验观测结果表明,有机肥和氮素化肥配合施用可以显著提高土壤的持水容量,并有效地抑制裸土蒸发.连续4年适量的稻草和化肥氮素配施与单施化肥相比,粘盘黄褐土的田间持水量增加20%左右,作物初萎土壤含水量有所降低,因而有效水储量增加;裸土蒸发过程中,在0～8×104Pa吸力范围内,随着土壤含水量降低,施有机肥的土壤吸力陡增,失去单位数量的水需要做更多的功,因而蒸发强度减弱,15d累积蒸发量比单施化肥的土壤减少26%.秸杆与化学氮肥配合施用,可以明显增强土壤的蓄水抗旱机制.     

Optimization of pressure gauge locations for water distribution systems using entropy theory

It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems.     

中国表层水体沉积物中多环芳烃源解析及评价

采用索氏提取气相色谱-质谱法测定中国6个重点水体表层沉积物中16种多环芳烃的含量。各化合物含量范围分别为长江6.20~163 ng/g、淮河7.90~249 ng/g、海河12.1~401 ng/g、松花江5.75~152 ng/g、太湖29.1~2 810 ng/g和滇池19.1~795ng/g;16种多环芳烃的总量分别为：长江1 147 ng/g、淮河1 723 ng/g、海河2 595 ng/g、松花江793 ng/g、太湖12472 ng/g、滇池3 714 ng/g,属中等污染水平。利用特征分子比值法分析结果表明6条水体表层沉积物中PAHs均可能以燃料（包括柴油、汽油、煤、木材）燃烧以及焦化污染为主。淮河和滇池还可能存在轻微石油泄漏污染。利用沉积物质量基准法（SQGs）和沉积物质量标准法分别对6条水体表层沉积物中多环芳烃的风险评估表明严重的多环芳烃生态风险在这些水体表层沉积物中不存在,但长江、淮河、松花江、海河均可能存在一定的潜在风险,负面生物毒性效应会偶尔发生,风险主要来源于荧蒽和菲。太湖和滇池水体中存在的潜在多环芳烃风险种类较多,风险主要来源于菲、荧蒽、芘、苯并（a）蒽、苊和蒽,对水生生物毒性效应较高,有必要进行更深入细致的调查研究高风险区域底栖生物的受损状况、污染来源和途径,以制定合理的污染控制对策。     

水环境生物监测的发展方向与核心技术

水环境生物监测是环境监测的重要内容,它应重点说清环境胁迫的生物效应。简述了总量管理、流域管理、风险管理、生态管理等环境管理对水环境生物监测有迫切需求,应引入＂生态系统健康＂、＂生物完整性＂、＂环境胁迫＂、＂全排水毒性＂等现代环境生物监测的基本概念,建立水环境生物监测技术发展的理论基础,发展生物完整性、综合毒性等监测与评价核心技术;革新现行监测方法体系,建立包括QA/QC、快速方法等支持系统在内的现代水环境生物监测业务化方法体系;创新评价技术体系,建立水环境生态健康评价及综合毒性评价指标体系、基准及分级管理标准,确立水环境质量管理的生物学目标。     

顶空气相色谱法测定水中苦味酸

建立了顶空气相色谱法测定水中苦味酸的新方法,将10 mL水样中的苦味酸衍生化后,直接取顶空气进样,保留时间定性,外标法定量。结果表明,该法在0～25μg/L浓度范围内有良好的线性关系(r=0.999 5),加标回收率为90.2%～107.6%,相对标准偏差为6.8%,检出限为0.02μg/L,能同时满足饮用水源地水和废水中苦味酸的测定要求。     

Polycyclic aromatic hydrocarbons in river sediments from the western and southern catchments of the Bohai Sea, China: toxicity assessment and source identification

The concentration, distribution, and origin of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated in river sediments from the western and southern catchments of the Bohai Sea, China. A toxicity assessment of 28 sediment samples collected from 15 main rivers was conducted by utilizing threshold and probable effect concentrations (TEC and PEC, respectively) derived from consensus-based sediment quality guidelines. The concentrations of total PAHs (∑PAH₁₆) ranged from 0.14 to 10,757 μg/kg dry weight (mean?=?1,368.6 μg/kg). The high concentrations of PAHs found in Binhai New Area of Tianjin and Binzhou City are likely the result of rapid population and heavy industry growth, resulting in elevated point and nonpoint source inputs of PAHs. Of the samples collected, samples 1 and 10 (7.1 % of the total) were categorized as toxic since some of the PAH concentrations exceeded the corresponding PECs. Twenty samples were classified as nontoxic, with both the individual PAH and the∑PAH₁₆ concentrations falling below the corresponding TECs. Analyses of selected PAH isomer ratios aided in the identification of PAH origins, allowing for a discrimination between pyrogenic and petrogenic sources. Spatial variability confirmed source heterogeneity within the study area. The most significant PAH-associated contamination was found in the Beitang River and Ji Canal, which are located in Binhai New Area. The magnitude of contamination and the likelihood of an ongoing influx of PAHs support the need for a better understanding of pollution sources and methods for both control and sediment restoration.     

生态工程治理玄武湖水污染效果的监测与评价

选取总磷、总氮、叶绿素a、浮游生物、浮游植物等多项环境监测指标,对利用生态工程治疗玄武湖水环境污染的效果进行了环境监测与评价。指出生态工程治理玄武湖水环境污染效果显著,经过治理使湖水中生物多样性大大增加,浮游植物大幅减少,湖水透明度增加,总磷、总氮等主要指标大幅下降,生态工程区中的水环境已从高度富营养化降到中度富营养化。