低山丘陵区农业景观格局对害虫-捕食性天敌食物网的影响

农业集约化导致景观破碎化、均质化程度加深.景观斑块的组成及合理布局带来的农业景观高异质性是维持区域生物多样性的关键.该文选择具有典型低山丘陵地貌的辽宁省建平县为研究区,在食物网水平上探究区域农业景观格局对生物多样性的影响.选取20个样区,在明晰区域景观特征、分析害虫-捕食性天敌食物网结构的基础上,采用回归分析和最优模型...     

不同地质成熟度家用燃煤燃烧颗粒物及多环芳烃的排放特征

选取了7种不同成熟度的原煤,模拟煤炭家用取暖燃烧过程,基于稀释通道采样方法,测定了PM_2.5、有机碳（OC）、元素碳（EC）和多环芳烃（PAHs）的排放因子（Emission factors,EFs）,分析了原煤自身特征参数与污染物排放因子的关系,并计算了原煤排放PAHs的特征比值.结果表明,地质成熟度高的无烟煤燃烧PM_2.5、OC、EC和PAHs的排放因子最低,分别为（0.28±0.07）、（0.07±0.04）、（0.003±0）g·kg^-1和（1.15±0.84）mg·kg^-1.随着地质成熟度的降低,PM_2.5、OC、EC和PAHs的排放因子呈波动上升的趋势,具有中等地质成熟度（挥发分为28.08%）的烟煤PM_2.5、OC和PAHs的排放因子最高,分别为（5.17±0.33）、（2.50±0.93）g·kg^-1、（240.39±180.55）mg·kg^-1,比地质成熟度高的无烟煤高出1～2个数量级.相关关系...     

Performance and microbial response during the fast reactivation of Anammox system by hydrodynamic stress control

Anaerobic ammonium oxidation （Anammox） has become a promising method for biological nitrogen removal. However, this biotechnology application is always limited due to the low growth rate and biomass yield of Anammox bacteria. This study investigated the process of fast reactivation of an Anammox consortium idled for 2 years uia hydrodynamic stress control. The results showed that the Anammox system was efficiently and quickly reactivated by shortening of the hydraulic retention time （I-IRT） of the reactor from 12 to 6 hr within 68 days of operation. Moreover, at a 4-hr HRT with an influent total nitrogen loading rate of 1.2 kg N/（m3.day）, the reactor maintained high biological performance with an ammonium removal loading rate of 0.52 kg N/（m3.day） and a nitrite removal rate of 0.59 kg N/（m3.day）. In the reactivated Anammox reaction, the stoichiometric coefficients of NH4-N to NOE-N and NH4-N to NO4-N were 1：1.04± 0.08 and 1：0.31 ± 0.03, respectively. The specific Anammox activity and hydrazine oxidoreductase activity, both of which represent the degree of Anammox bacteria present, increased as the hydrodynamic stress increased and were maximally （125.38 ± 3.01 mg N/（g VSS.day） and 339.42 ± 6.83 μmol/（min.g VSS）, respectively） at 4-hr HRT. Microbial response analysis showed that the dominant microbial community was obviously shifted and the dominance of Anammox bacteria was enhanced durinR the hydrodynamic selection.     

校园噪声现状分析研究——以哈尔滨工业大学(威海)为例

以哈工大(威海)为例,对校园噪声进行监测和分析,以探明当前中国大学校园噪声污染状况。结果表明,校园大部分区域的声环境处于达标水平,噪声污染主要集中在校门口、体育场和校园广场等区域,为轻度污染型,且白天比晚上的噪声污染严重,休息日的噪声明显高于工作日。校园施工产生的噪声声级较高,容易产生瞬时高分贝噪声,应采取相应的降噪、除噪措施。     

锑矿废水污染应急处置实验研究

为了治理饮用水源地锑矿废水泄漏对水体的污染,使其达到饮用水水质标准,研究了聚合硫酸铁、氯化铁等3种混凝类物质及活性炭粉、蒙脱石粉等4种吸附类物质对含锑废水的处理效果.结果表明,聚合硫酸铁、氯化铁、硫酸亚铁对含锑废水具有良好的处理效果,去除率均达到90％以上.同时,进一步研究了聚合硫酸铁混凝结合硫化钠沉淀处理废水中的锑,废水经两级处理,废水中锑离子质量浓度从3.8400 mg/L降至0.002 7mg/L,达到国家《生活饮用水卫生标准》(GB 5749-2006)水质标准(Sb质量浓度＜0.005 0 mg/L).     

Comparison of Machine Learning Models Performance on Simulating Reservoir Outflow: A Case Study of Two Reservoirs in Illinois,U.S.A.

Reservoir outflow is an important variable for understanding hydrological processes and water resource management. Natural streamflow variation, in addition to the streamflow regulation provided by dams and reservoirs, can make streamflow difficult to understand and predict. This makes them a challenge to accurately simulate hydrologic processes at a daily scale. In this study, three Machine Learning (ML) algorithms, Random Forest (RF), Support Vector Machine (SVM), and Artificial Neural Network (ANN), were examined and compared to model reservoir outflow. Past, current, and future hydrologic and meteorological data were used as model inputs, and the outflow of next day was used as prediction. Simulation results demonstrated that all three models can reasonably simulate reservoir outflow. For Carlyle Lake, the coefficient of determination and Nash–Sutcliffe efficiency were each close to one for the three models. The coefficient of determination, relative mean bias, and root mean square error indicated that the SVM performed better than the RF and ANN, but the SVM output displayed a larger relative mean bias than that from RF and ANN. For Lake Shelbyville, the ANN model performed better than RF and SVM when considering the coefficient of determination, Nash–Sutcliffe efficiency, relative mean bias, and root mean square error. The study results demonstrate that the three ML algorithms (RF, SVM, and ANN) are all promising tools for simulating reservoir outflow. Both the accuracy and efficacy of the three ML algorithms are considered to support practitioners in planning reservoir management.     

武汉典型下垫面降雨径流PAHs污染特征研究

以武汉城区7类典型下垫面降雨径流中16种多环芳烃(polycyclic aromatic hydrocarbons, PAHs)为主要研究对象,对径流中常规污染物、PAHs浓度、种类差异与来源等进行研究。结果表明,武汉市7类下垫面降雨径流中,在常规污染物方面,沥青路面和水泥路面的污染程度最高,瓦屋面污染程度最低;而在PAHs方面,沥青路面径流∑16PAHs初始浓度最高,2类油毡屋面(工业园和教工宿舍)次之,其他4类下垫面较低。油毡屋面径流PAHs主要由蒽(ANT)和菲(PHE)组成,而沥青路面、水泥路面等其他5类下垫面径流中主要含有PHE、芘(PYR)和荧蒽(FLA)等。油毡屋面(工业园和教工宿舍)、水泥屋面和瓦屋面等4类屋面径流中主要污染物是2～3环PAHs,而沥青路面和水泥路面径流中则以4～6环PAHs为主。     

邻苯二甲酸二甲酯在离体人红细胞内的分布和含量研究

邻苯二甲酸酯类污染物(PAEs)在环境中普遍存在,可沿食物链富集,危害人体健康。本文利用荧光光谱法和高效液相色谱法(HPLC)探究了邻苯二甲酸二甲酯(DMP)在离体人红细胞内的分布情况。结果表明,红细胞在310 nm、490 nm和609nm处各具有一个荧光特征峰,其来源分别为:红细胞内的蛋白;还原型烟酰胺腺嘌呤二核苷酸磷酸(NADPH)、黄素腺嘌呤二核苷酸(FAD)和膜脂;锌卟啉和原卟啉。DMP染毒后,310 nm处的荧光峰出现明显下降,其原因为进入红细胞内的DMP与蛋白发生了结合;490 nm和609 nm处的荧光峰变化很小。高效液相色谱(HPLC)实验结果表明,DMP能透过红细胞膜进入细胞内部,其进入量随暴露量增加而增加,进入量和暴露量的比值随暴露量增加而减少。上述研究成果能加深对PAEs在血液运输过程中与红细胞毒性作用的理解,可为PAEs的危险性评估和相关疾病预防提供数据参考。     

Identifying sources and assessing potential risk of heavy metals in soils from direct exposure to children in a mine-impacted city, Changsha, China

Heavy metal pollutants in soils can usually enter the human body and pose heath risks through a soil-crop-human body pathway (indirect exposure) or soil-human body pathway (direct exposure). Previous studies often neglected the direct exposure in human health risk assessment, especially for children. We collected surface soil samples from urban and suburb areas in Changsha City, China, to analyze the content ofAs, Cd, Hg, Ni, Pb, and Zn. A combination of principal component analysis, geostatistics, and triangulated irregular network (TIN) model was successfully used to discriminate the sources of heavy metals. The direct exposure method, sequential indicator simulation, and geographical information system (GIS) technologies were used to perform a health risk assessment of heavy metal exposure to children living in the study area. Results show that heavy metal contamination in Changsha may originate from coal usage and industrial activities. One thousand equiprobable realizations suggest that not all sites within the study area may be suitable for housing or allotments without remediation. Most high hazard indexes are located in the suburb and mining areas. Moreover, arsenic presents a high health risk in comparison with other elements. Compared with inhalation and dermal contact in direct soil exposure, soil ingestion is the largest contribution to potential health risks for children. This study indicates that we should attach great importance to the direct soil exposure for children's health.