模糊综合评价在天然水体水质评价中的应用研究

采用模糊数学方法,对河网地区面源污染影响较大的代表性河流的水质状况进行综合评价研究。根据监测断面水质污染特点,确定了8个指标作为评价因子,建立了评价因素矩阵,计算出影响因子的权重。在此基础上,提出了模糊综合评价的水质级别,证明该河网地区的污染物主要是氮、磷和有机物。     

活性炭吸附室内空气中挥发性有机化合物

活性炭吸附室内空气中挥发性有机化合物的１０％穿透时间与气相浓度及挥发性有机化合物的种类有关,通过对苯、甲苯和丙酮的实验研究,得出了由高浓度估算室内低浓度时炭床１０％穿透时间的经验公式ｔｂ,１＝ｔｂ,ｈ（Ｃ０,１／Ｃ０,ｈ）＾ａ,其中ａ值是与炭床性能及挥发性有机化合物种类有关的参数,可通过实验确定。     

Measurements of peroxyacyl nitrates (PANS) in Mexico City: implications for megacity air quality impacts on regional scales

Peroxyacyl nitrates (PANs) were measured using gas chromatography with electron capture detection (GC/ECD) in north central Mexico City during February–March of 1997. Peroxyacetyl nitrate (PAN) was observed to exceed 30 ppb during five days of the study, with peroxypropionyl nitrate (PPN) and peroxybutryl nitrate (PBN) reaching 6 and 1 ppb maximum, respectively. Levels of total PANs typically exceeded 10 ppb during the period of measurement and showed a very strong diurnal variation with PANs maximum during the early afternoon and falling to less than 0.1 ppb during the evening hours. These levels of PANs are the highest reported values in North America (and the world) for an urban center, since levels of approximately 30 ppb were reported during the late 1970s in the Los Angeles area (South Coast Air Basin, Tuazon et al., 1978). Hydrocarbon measurements indicate that the levels of olefins, specifically butenes are significant in Mexico City. A time series taken of source indicator hydrocarbons taken before and during a Mexican National Holiday with reduced automobile traffic clearly show that mobile sources of butenes are as important as liquefied petroleum gas. Observations of 10–40 ppb C methyl-t-butyl ether (MTBE) are consistent with MTBE/gasoline fuel usage as a source of isobutene and formaldehyde. Both these reactive species can lead to increased oxidant and PAN formation. The strong diurnal profiles of PANs are consistent with regional clearing of the Mexico City air basin on a daily basis. Estimates are given using a simple box model calculation for a number of key primary and secondary pollutant emissions from this megacity on an annual basis. These calculations indicate that megacities can be important sources of both primary and secondary pollutants, and that PANs produced in megacity environments are likely to contribute strongly to regional scale ozone and aerosol productions during long range transport.     

改善深圳河水质的补水方案及生态影响初步分析

深圳河旱季天然径流量小而污染负荷高,为了改善河流水质,在削减入河污染物的同时有必要采取补水措施。利用水质模型,计算了不同污水处理率下,分别以污水资源化再生水、珠江口海水和大鹏湾海水为补水水源时,深圳河达到基本不黑臭所需的补水量。讨论了补水方案对河流水质、盐度、水动力条件的改变及其对生态系统的影响。研究表明,引海水对河流生态系统的冲击不容忽视。而污水资源化是较优的补水方案。     

收入差距是否影响环境质量?——国内外研究综述

近年来,收入差距扩大与环境质量恶化成为许多国家同时面临的问题,也让一些经济学家开始思考,这两者之间是否存在关联。继20世纪90年代环境库兹涅茨曲线提出以来,一些研究发现不仅收入的绝对水平会对环境质量产生影响,收入差距对环境质量也有影响。本文对这一课题的理论研究进行了梳理,发现现有理论中收入差距对环境质量的影响途径主要有三条。第一条途径是消费者途径,即收入差距影响着以消费为主的个人经济行为,进一步影响着社会消费总量和消费结构,及其过程中产生的污染总量。第二条途径是企业途径,即认为收入差距的扩大会削弱环保型产品的正外部性,不利于环保技术的创新活动,对未来环境质量的改善产生动态影响。第三条途径是政府途径,即认为收入差距会影响相关的环境政策方式与强度选择;而且在不同的社会政策决策机制下,收入差距对环境政策的影响也是不同的,现有的社会决策机制分析框架主要有两种——权利权重型社会决策规则和简单多数规则。此外,本文还对现存的主要实证研究进行了总结,发现大多数研究结论都支持收入差距对环境质量存在着影响,但这种影响并不是线性的。一方面,收入差距对环境的影响与研究的污染物种类有关,大多数研究都显示,收入不平等对CO 2排放和土壤污染存在着负向影响,但有关收入差距对空气污染和水污染影响的研究结论并不统一或并不显著。另一方面,这种影响还与经济发展水平相关,在高收入国家与低收入国家是不同的,存在着阈值效应。最后本文总结了针对中国的研究现状,讨论了其在我国的适用性。     

环境资源的量化模型及估算指标体系

本文依据区划环境标准，提出了环境资源的成本概念－环境成本。     

空气微生物对铜陵市环境质量的指示作用

所测铜陵市区空气的平均细菌含量约４１８１．５ＣＦＵ．ｍ－３，总菌含量约４４９５．９ＣＦＵ．ｍ－３。与许多中国的大中城市比，污染不重，结果指示铜陵空气尚处于正常状态之中。     

Time and cost characterisation of emissions from non-road diesel equipment for infrastructure projects

The construction process contributes to pollutant emissions, particularly through the operation of diesel- and gasoline-powered equipment. In the past decade, a series of investigations were undertaken to quantify these emissions for a variety of non-road construction equipment performing different activities and undergoing different duty cycles, and a model to estimate quantities of six types of pollutant was developed. This paper uses that model to estimate emissions for four street and utility construction projects which no one has done previously. We combined information from company records with standard construction industry manuals to estimate total emissions for the projects and to examine the pollution patterns and magnitudes. The street construction projects all had similar emission profiles with a large peak at the beginning and a steady output of emissions throughout the duration of the project. For example, in two of the projects studied, half of all CO₂ emissions were produced before the projects were 40% completed. Results showed that demolition and earthwork are the activities with the largest contribution. The equipment types with the largest contribution are backhoes, front-end loaders, bulldozers and trenchers. Trenchers, for example, produced 30% of all emissions on the projects on which they were used.     

丹江口水库水质空间异质性多指标监测综合分析技术及效果

为深入分析丹江口水库水质时空差异性,探索影响水质的重要因子,提供更具综合性的水质分析方法,基于5个不同观察点,监测水质理化指标和浮游细菌(真菌)群落多样性指标,并采用判别分析法、配对T检验法、直接相关和典型相关分析法进行分析。结果表明：丹江口库区5个观察点的水质在2016年和2017年分别属于良好状态和优秀或良好状态,但是判别分析法显示水质理化指标在5个观察点上整体存在显著差异;浮游细菌(真菌)群落多样性指标在5个观察点上整体存在显著差异; 5个观察点水质理化性质在2 a的2个时期上均无显著性差异,即水质营养状态无显著变化,但两者之间存在显著相关性;对丹江口库区的水质理化指标群与浮游细菌(或真菌)群落多样性指标群按照2个不同时期分别进行典型相关分析,发现水质理化指标的变化趋势与浮游细菌群落多样性指标变化趋势一致;依据所有水质理化指标和浮游真菌(或细菌)群落多样性指标进行综合判别分析,可对不同观察点进一步精细分类;通过典型相关分析发现浮游真菌(或细菌)群落多样性指标可以间接指示或反映水质变化的特点;环境因子（水质理化指标）中重要指标包括X₃(COD)、X₅(NH₃-N)、 X₇(Chl-a)和X₈(SD);浮游细菌群落多样性重要指标包括Y₁(序列条带)、Y₂(OTU数)、Y₃(Ace指数)和Y₄(Chao1指数);浮游真菌群落多样性重要指标包括Y₁(序列条带)、Y₂(OTU数)和Y₃(Ace指数) 。本研究采用的多指标综合分析技术较单指标逐一分析更能全面客观地反映水质变化全貌,可为完善和丰富水质环境监测数据综合分析技术手段提供一定的参考。本研究结果可为相关管理部门监测和改善南水北调中线水源区水质并制定政策提供基础数据和参考依据。     

大型溞投放密度对湖库水体水质改善及底泥污染物影响

向北京市沙河水库投放大型溞(Daphnia magna),利用其摄食藻类、促进悬浮颗粒态污染物沉降的特性,以提升水体的透明度,为后续沉水植物群落的恢复创造条件,并探索大型溞的投放密度,以及投放后对水质及底泥主要污染物的影响。结果表明：向沙河水库投加大型溞的最佳密度为5~15 ind·L⁻¹;在该条件下,水体透明度可在3~5 d由40 cm提升至100 cm,浊度由19.7 NTU降至3 NTU,藻密度由2.4×10⁶ cell·mL⁻¹降至(4~6)×10⁴ cell·mL⁻¹;大型溞可在沙河水库长期存活,并可长期抑制藻类、维持水体的透明度;水体COD并未发生明显改变;大型溞的分泌物促进了悬浮颗粒态氮、磷的沉降,使TN和TP的去除率分别达到70.2%和54.9%;由于投溞后藻类浓度迅速下降,藻对NH₃-N的吸收量降低,使水体NH₃-N升高了32.2%;底泥中有机质、TN、TP均出现了一定程度的升高。针对于湖库水体透明度低的问题,应投放适宜密度的大型溞,调整水质状态,并结合水中藻类、底泥污染物等条件,综合考虑有效改善水质的方法。