兰州市大气污染对绿化树种叶绿素含量的影响

为了筛选出兰州市大气污染的抗性树种和敏感监测树种,对树种的叶绿素a、叶绿素b含量进行了测定,运用spss11.5软件分析。研究发现:同一绿化树种在不同功能区的叶绿素含量不同,存在极显著性的差异。随着功能区污染程度的加深,绿化树种的叶绿素含量(ωa、ωb、ωa+ωb)呈现减小的趋势,但叶绿素ωa/ωb值却呈现增大的趋势。绿化树种抗污染能力为:杨树小叶黄杨椿树国槐圆柏,兰州市主要功能区的污染程度为:兰炼厂区兰化厂区橡胶厂西关西站交大兴隆山。     

三清山主要树种重金属污染与华东各山的比较

对江西三清山常见树木叶片重金属含量进行分析测定，并与黄山、庐山、西天目山、乌岩岭同种树种进行了比较。结果表明：三清山已受到一定程度的污染，树木叶片对重金属具有富集作用，富集特性比较：铅：苦槠〉樟〉木荷〉青岗；铜：苦槠〉甜槠〉樟〉木荷〉青岗；镉：甜槠〉樟〉木荷〉苦槠〉青岗；锌：青岗〉甜槠〉苦槠〉樟〉木荷，４种重金属富集能力比较为镉〉铜〉锌〉铅。     

兰州地区绿化工程建设中水资源的综合利用与可持续发展

针对兰州市南北两山绿化工程用水状况的发展趋势,根据绿化工程的用水现状,建立起科学的用从机制,对黄河水资源实施有计划的和保护性的综合利用,这对维护黄河水系的综合平衡和可持续性发展将起到积极的作用。     

南京绿化废弃物不再一埋了之

南京首个城市园林废弃物资源化利用与示范工程,今年10月启动建设,明年6月将试运行,可填补该市绿化垃圾资源化利用空白。在12日举行的南京首届园林新技术新成果新材料推介会上,承担该项目的南京登博生物科技有限公司总经理蒋明透露,工程投产后,年消化利用2000t绿化废弃物。     

石河子市大气硫酸盐化速率与二氧化硫浓度的相关性分析

对石河子市2000-2002年间硫酸盐化速率与二氧化硫监测数据进行了相关分析,结果表明,二者浓度之间具有显著的相关性。并由此建立了符合各监测点环境状况的回归方程。     

城市绿化覆盖率与大气环境的关系探讨

从绿化覆盖率与气温的关系 ,绿化覆盖率与大气环境质量的关系 ,城市绿化的合理布局等 3个方面探讨了城市绿化覆盖率与大气环境之间的关系 ,并对城市规划和绿化布局提出了建议。     

二氧化氯的消毒作用及制备方法研究

论述了二氧化氯作为饮用水消毒剂与其他各类常用的消毒剂相比具有的特点,讨论了二氧化氯的最佳投入方式及制备方法,研究出以氯酸钠与硫酸为原料反应生成二氧化氯的新方法,首次采用对人体无毒无害的Ｇ型还原剂,新方法具有安全、可靠、产气纯度高的经济等优点。     

成都气象要素等级对大气污染的改善作用研究

为找到对成都空气质量有改善作用的气象要素等级,量化成都气象条件对大气污染物的影响,对2015—2018年成都环境监测站空气质量监测数据和温江国家气候观象台同时段的气象观测资料进行了研究分析。结果表明：(1)成都中部地区的空气质量污染较为严重,全年主要以PM_2.5和O₃污染为主,占比达75%,2015—2018年成都的PM_2.5污染呈下降趋势,而O₃污染虽有所波动但没有显著改善。(2)PM_2.5持续重污染过程中,过去12 h降水量和过去24 h降水量均大于1 mm,均为有效降水,大于2.5 mm对PM_2.5污染的改善作用显著增强;相对湿度低于70%对中度及以上PM_2.5污染的改善作用同步增加,低于40%对轻度PM_2.5污染的改善作用较为明显,优良天气的发生概率显著增加;风速大于1 m/s时PM_2.5浓度随风速的增大而减小,大于2 m/s对PM_2.5浓度的改善作用显著加强。...     

多因素作用下高校阶梯教室生物气溶胶的分布特性研究

采用自然沉降法和撞击法两种实验测试方法,对比分析在不同季节、自然通风和人员活动多因素作用下的高校阶梯教室室内生物气溶胶分布特性及变化规律。结果表明:阶梯教室夏季室内生物气溶胶浓度高于冬季;教室内无通风和人员活动的情况下,室内生物气溶胶浓度大幅度下降,其平均衰减率为68%;教室内有自然通风时,室内生物气溶胶浓度与室外的趋于一致,室外空气源是影响室内生物气溶胶浓度的重要因素;人员活动会显著提高室内的生物气溶胶浓度,同时使得粒径分布状态发生改变,粒径为3.3μm~7.0μm生物气溶胶的比例从27.6%增加到59.8%。     

污水处理中的新型填料及对磷的去除作用研究现状

滤料是生物滤池、生物接触氧化池、人工湿地等污水处理单元中的核心组成部分,其对处理效果和运行控制极为重要。随着污水处理中这几项污水处理工艺的发展,滤料的研究也受到越来越多的重视。本文重点介绍了常规滤料以及几种新型填料:生物陶粒、生物填料、组合填料等,介绍了这几种新型滤料的工艺特性及制备方法,并通过应用实例研究其对磷的去除作用,并与传统填料做了对比。最后,在此基础上,对未来新型填料的研究提出了展望。     

采样时间对ANDERSEN采样器采样效果的影响

在室内用ANDERSEN生物粒子采样器进行了不同采样时间对采集空气细菌和真菌粒子浓度,粒数中值直径效果的研究,结果表明,在1－12min内,采集的空气细菌和真菌粒子浓度随采样时间的增加而减少,呈明显的负相关关系,相关系数分别为－0．903和－0．688,P值均大于0．05,另外,在采样过程中,空气真菌比细菌耐受采样空气冲击力的能力强,采样时间对空气细菌和真菌粒子的粒度分布和粒数中值直径的影响不明显。     

废水污染物总量监测中采样方法的研究

通过对21家有代表性的废水污染源进行现场采样、排放曲线分析、采样频率优化的研究,确定总量监测中采样频率优化结果,为污染源总量控制监测提供技术指导。     

Function Approximation and Documentation of Sampling Data Using Artificial Neural Networks

Biodiversity studies in ecology often begin with the fitting and documentation of sampling data. This study is conducted to make function approximation on sampling data and to document the sampling information using artificial neural network algorithms, based on the invertebrate data sampled in the irrigated rice field.Three types of sampling data, i.e., the curve species richness vs. the sample size, the curve rarefaction, and the curve mean abundance of newly sampled species vs.the sample size, are fitted and documented using BP (Backpropagation) network and RBF (Radial Basis Function) network. As the comparisons, The Arrhenius model, and rarefaction model, and power function are tested for their ability to fit these data. The results show that the BP network and RBF network fit the data better than these models with smaller errors.BP network and RBF network can fit non-linear functions (sampling data) with specified accuracy and don't require mathematical assumptions. In addition to the interpolation, BP network is used to extrapolate the functions and the asymptote of the sampling data can be drawn. BP network cost a longer time to train the network and the results are always less stable compared to the RBF network. RBF network require more neurons to fit functions and generally it may not be used to extrapolate the functions. The mathematical function for sampling data can be exactly fitted using artificial neural network algorithms by adjusting the desired accuracy and maximum iterations. The total numbers of functional species of invertebrates in the tropical irrigated rice field are extrapolated as 140 to 149 using trained BP network, which are similar to the observed richness.     

富集采样法监测空气和废气样品时采样体积的确定方法

讨论了富集采样法监测空气和废气样品时确定采样体积的主要因素,给出了富集采样法监测空气和废气样品时采样体积的确定方法和实例。     

Sampling Scale Effects in Random Fields and Implications for Environmental Monitoring

The concept of a sampling scale triplet of spacing, extent and support is used to define the spatial dimensions of a monitoring network or a field study. The spacing is the average distance between samples, the extent is the size of the domain sampled and the support is the averaging area of one sample. The aim of this paper is to examine what is the bias and the random error (uncertainty) introduced by the sampling scale triplet into estimates of the mean, the spatial variance and the integral scale of a variable in a landscape. The integral scale is a measure of the average distance over which a variable is correlated in space. A large number of two dimensional random fields are generated from which hypothetical samples, conforming to a certain sampling scale triplet, are drawn which in turn are used to estimate the sample mean, spatial variance and integral scale. The results indicate that the biases can be up to two orders of magnitude. The bias of the integral scale is positively related to the magnitude of any of the components of the scale triplet while the bias of the spatial variance is different for different components of the scale triplet. All sampling scale effects are relative to the underlying correlation length of the variable of interest which is closely related to the integral scale. The integral scale can hence be used for sampling design and data interpretation. Suggestions are given on how to adjust a monitoring network to the scales of the variables of interest and how to interpret sampling scale effects in environmental data.     

CODMn重新稀释取样体积的推定

对原CODMn法测地表水二次取样体积进行了推导,建立了实际适用取样体积公式,具有一定的适用性。     

Sampling of Sparse Species with Probability Proportional to Prediction

In this article, a 3P sampling (Probability Proportional to Prediction) approach is presented for surveying sparse species connected to certain types of substrates. The method uses the surveyors judgement of the probability of finding the species on a substrate as the base for selection of substrates for species inventories. The method is presented together with estimators, variances and variance estimators. The method is first presented for sampling based on all substrates in a study area and then as a subsampling technique in a two-stage design in which plots or strips are selected in a first stage. The presented approach was evaluated as a subsampling technique in a strip survey of calicioid lichen species associated with coarse broadleaf trees. In comparison with a simple random subsampling without replacement, 3P subsampling was in one study area found to be an improvement with 30–55% in terms of standard errors. The improvement was more modest in the other study area, only between 10–16%. The strip survey with 3P subsampling was more cost-efficient than a strip survey without subsampling except in one case. Based on the results in the test, 3P sampling seems to have a potential for sampling sparse species.     

石河子蘑菇湖水库富营养化成因及防治对策

15年来，蘑菇湖水库一直处于富营养化状态，但污染物排放总量没有随着城市经济与人口的增加而成比例增加，相对污染物进库勘晓少。本文主要从水质状况、底泥、水生生物三方面入手，分析了蘑菇湖水库富营养化的成因，阐述水体富营养防治对策的同时。提出了蘑菇湖水库治理的建议。     

A Study of Sorptive Loss Patterns for Reduced Sulfur Compounds in the Use of the Bag Sampling Method

In this work, the basic properties of the bag sampling method were examined and characterized in terms of recovery rate with respect to four reduced sulfur compounds (RSC) including H₂S, CH₃SH, DMS, and DMDS. For this comparative study, two types of calibration approaches were performed to evaluate the relative RSC loss due to bag sampling. As a reference calibration tool, a syringe dilution (SD) method was applied. The working standards prepared by diluting the primary standard in a gas-tight syringe (as a mixing chamber) were injected to the GC/PFPD through a loop-injection system to yield a background calibration information. In contrast, the target calibration was performed based on a bag dilution (BD) method. To this end, working standards for multiple calibration points were prepared by two different bag types (Tedlar bag (TB) and polyester bag (PB)). These standards were then drawn by the same syringe and injected into the GC/PFPD via loop. On the basis of these comparative analyses, both absolute and relative differences in RSC recovery rates (RR) were evaluated (e.g., comparison of wall-loss effect). The results indicate that TB has a mean RR of 87% for the four RSC with their values ranging from 82 (CH₃SH) to 91% (DMDS). On the other hand, the results of PB generally exhibited slightly reduced RR with their mean values of 77% (range: 73% of H₂S to 83% of DMS). The results of this study generally suggest that the losses of RSC samples, while inevitable with the bag sampling method, exhibit certain patterns between different RSCs and between different grab sampling materials.     

Temporal Trends of Young-of-Year Fishes in Lake Erie and Comparison of Diel Sampling Periods

We explored temporal trends of young-of-year (YOY) fishes caught in bottom trawl hauls at an established offshore monitoring site in Lake Erie in fall during 1961–2001. Sampling was conducted during morning, afternoon, and night in each year. Catches per hour (CPH) of alewife (Alosa pseudoharengus) YOY were relatively low and exhibited no temporal trend. This result was consistent with the species’ intolerance to Lake Erie’s adverse winter water temperatures. Gizzard shad (Dorosoma cepedianum) YOY decreased sharply after 1991, which was consistent with recent oligotrophication of the lake. Following the establishment in 1979 and rapid increase of white perch (Morone americana) YOY, white bass (Morone chrysops) and freshwater drum (Aplodinotus grunniens) YOY decreased. Trout-perch (Percopsis omiscomaycus) YOY decreased during 1986–1991, but recovered to previous levels during 1991–2001. The recovery coincided with the resurgence of mayflies (Ephemoptera) in the lake. CPH of spottail shiner (Notropis hudsonius) and emerald shiner (N. atherinoides) YOY exhibited no temporal trend between 1961 and the late 1970s to early 1980s. CPH of yellow perch (Perca flavescens) YOY decreased during 1961–1988, and walleye (Sander vitreum) YOY increased overall during the time series. These observations were consistent with published studies of adults in the region. CPH of 4 of the 10 species of YOY considered were greatest during night. CPH for walleye YOY was higher in the morning than in the afternoon, but there was no significant difference between night and morning abundances. The results suggest that (1) CPH of YOY fishes may be a useful monitoring tool for Lake Erie, and (2) offshore monitoring programs that do not include night sampling periods may underestimate recruitment for several common species.