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1.
Suspended particulate matter (SPM) was collected seasonally for 1 yr at third- and fifth-order sites in a blackwater stream on the coastal plain in South Carolina. Fatty acids with carbon chain lengths from C(12)-C(32) were the most abundant component among the lipid classes examined with total concentrations varying from 8.5 to 60.2 microgL(-1). Unsaturated fatty acids predominated while significant concentrations of the even-chained saturated components C(24)-C(30) derived from cuticular plant waxes were also found. Concentrations of aliphatic alcohols, with carbon chain lengths between C(16) and C(30), ranged from 0.52 to 2.73 microgL(-1) and was dominated by the higher molecular weight compounds (C(22)-C(30)) derived primarily from cuticular plant waxes. Total hydrocarbon concentrations ranged from 0.35 to 5.66 microgL(-1) and showed no discernible trends with time or consistent difference between sites. The hydrocarbon assemblage observed indicates that these components are entirely of biogenic origin with no detectable anthropogenic contribution.The ratios of unsaturated to saturated fatty acids and cuticular to noncuticular fatty acids and alcohols at both stream locations indicate that the organic detritus associated with SPM collected during November and January is of more recent origin and less processed than that collected in the spring and summer months. Lipid concentrations at the third-order site generally had higher and more variable concentrations of the lipid classes compared with the fifth-order site. The ratio of saturated to unsaturated fatty acids was higher at the third-order site indicating that the organic fraction of SPM at this site was of more recent origin and less decomposed. The ratios of cuticular to noncuticular fatty acids and alcohols support this conclusion. These results indicate an export of particulate lipids of higher carbon resource quality from upstream to lower stream reaches. 相似文献
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One-hundred and twenty-five domestic roof-collected rainwater supplies in four rural Auckland districts were investigated in a cross-sectional survey to determine water quality. Samples of cold faucet water were analysed for physico-chemical and microbiological determinands, including metals (zinc, copper and lead), bacterial indicator organisms--heterotrophic plate count (HPC), total coilforms (TC), faecal coliforms (FC), enterococci (ENT), bacterial pathogens including Salmonella spp., Legionella spp., Campylobacter spp., Aeromonas spp. and the protozoa, Cryptosporidium and Giardia. Twenty-two supplies (17.6%) exceeded one or more of the maximum acceptable values (MAV) or maximum guideline values for chemical determinands of the New Zealand Drinking Water Standards (NZDWS) and 70 (56.0%) supplies exceeded the microbiological criteria of < 1 FC/100 mL. Eighteen supplies (14.4%) exceeded the NZDWS MAV for lead of 0.01 mg/L and three (2.4%) exceeded that for copper, of 2 mg/L. Those supplies with lead or galvanised iron comprising part of the roof or collecting system were more likely to show lead contamination (p = 0.019) as were those supplies with a pH less than 7 (p = 0.013). The presence of the indicator organisms HPC, TC, FC and ENT were all significantly correlated with one another. Aeromonas spp. were identified in 20 (16.0%) supplies. There was a positive association between the presence of Aeromonas and the bacterial indicator organisms. Households reporting at least one member with gastrointestinal symptoms in the month prior to sampling, were more likely to have Aeromonas spp. identified in their water supply than those households without symptoms (odds ratio 3.22, 95% CI 1.15-9.01, p = 0.021). Salmonella typhimurium was detected in one of 115 (0.9%) supplies. Legionella spp. and Campylobacter spp. were not detected. There were 50 supplies sampled for protozoa (sampling criteria: > or = 30 FC or > or = 60 ENT). Cryptosporidium oocysts were detected in 2 (4%) of these. Giardia was not detected. This study demonstrates that roof-collected rainwater systems provide potable supplies of relatively poor physiochemical and microbiological quality in the Auckland area. Further research is required on Aeromonas spp. as potential indicators of both microbiological quality and health risk along with design and maintenance strategies to minimise contamination of potable roof-collected rainwater supplies. 相似文献
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作为空间发展和治理工具,国土空间规划体系中城市设计是实现国土空间高质量发展的重要支撑,如何培养与之相适应的城市设计人才是当前城市设计教学改革关注的焦点。新西兰奥克兰大学城市设计课程采用行动研究式工作坊特色教学,注重城市设计人才空间设计和治理能力培养,其经验值得我国高校城市设计教学参考和借鉴。奥克兰大学城市设计工作坊教学秉持CPS创新性教学理念,以行动研究为特色,注重学生的学术素养、批判思维、决策能力、研究独立性和社会责任感等综合能力培养。城市设计工作坊教学包括现状调查、发现问题、观点产生、找出解决方案和形成解决策略五个环节,教学内容涵盖空间设计和治理实施等系列课程。通过讲座、调研、阅读、研讨、咨询等教学方式,将城市形态学理论贯穿于项目实践教学,让学生多视角参与城市动态发展与建设的行动研究中,实现创新性解决问题的目的。以奥克兰滨海地块的更新与开发工作坊教学为例,介绍了行动研究方法在奥克兰大学城市设计教学中的应用及实践。针对我国城市设计工作坊教学中存在的问题,从强调综合能力培养、建构设计与治理并重的教学内容体系、运用行动研究的实践教学方法等对我国城市设计专业人才培养提出了具体建议。 相似文献
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Different classes of organic matter (OM) have been systematically investigated in sediments and suspended particulate matter (SPM) along the Danube River in order to understand causes of compositional changes. Analytical pyrolysis revealed the dominance of natural organic matter (NOM) in most of the samples. The predominance of aquatic biomass is evident mainly from the abundance of organonitrogen compounds and phenol distributions. As the river enters a forested gorge, the terrestrial component of the NOM in sediments is more significant. This is reflected in abundant methoxyphenols and a very high carbon preference index. SPM sample from a tributary shows a unique geochemical signature. It contains abundant carboxylic acids, amines, isoprenoids in the pyrolyzate, and is dominated by phytol and 24-methyl-cholesta-5,24(28)-dien-3β-ol in the extract, produced by a diatom bloom. Wax esters with a relatively high proportion of short, methyl-branched alkyl-chains appear together with abundant phytadienes and n-C17 alkane in some samples, suggesting a microbial origin. Anthropogenic OM from runoff and atmospheric deposition was evident from a minor input of polycyclic aromatic hydrocarbons (PAHs) originating from mixed combustion sources. Multivariate analysis using PAH data led us to define simple molecular ratios to distinguish the PAH composition in sand and silty sediments. The newly defined ratios are the alkylated phenanthrenes and anthracenes ratio (APA; C1-C3/C0-C3 phenanthrenes and anthracenes) and the PAH ring number ratio (RN; 5-6 ring parent PAHs/all parent PAHs). This demonstrates that alkylated, as well as 5-6 ring PAHs are better preserved in the finer than in coarser grained sediments. A ubiquitous, but minor input of petroleum-related contamination with a uniform composition was evident in all samples as revealed by the analysis of petroleum biomarkers. This study demonstrates that the investigation of different classes of riverine OM requires a detailed molecular analysis, applying a series of analytical techniques and adequate statistical data treatment. 相似文献
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Atmospheric fine particles (with a diameter less than 2.5 microm) and coarse particles (with a diameter between 2.5 and 10 microm) were collected simultaneously at an urban background site in Auckland, New Zealand, in the summer and winter of 2003. Major water-soluble ions, black carbon (BC), and some elements in the samples were analysed, and the data compiled into two sets. Selected trace gases (NH3, HONO, HNO3, and SO2) were also collected at the same time. Application of positive matrix factorisation to the particle data resolved five sources for the fine particles and five for the coarse particles. Weighted multiple linear regression was used to investigate the mass contributions of the sources. It was found that although natural sources had significant contributions to the coarse particles, anthropogenic sources dominated the contributions to the fine particles, particularly in winter. Significant seasonal changes of the sources were observed. Overall, sea salt and wind-blown soil had significantly stronger contributions in the summer; in contrast, the winter contribution of vehicle emissions, road dust, and industry and incineration sources was significantly higher. These seasonal changes may be explained by variations in meteorological conditions and atmospheric chemistry. The nonparametric correlations between the atmospheric concentrations of the trace gases and the mass contributions of the resolved sources demonstrate that these sources are realistic, providing a useful supplementary approach for the assessment of receptor modelling. 相似文献
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Davies H Weber P Lindsay P Craw D Pope J 《The Science of the total environment》2011,409(15):2971-2980
The Stockton coal mine lies at 700-1100 m above sea level in a mountainous orographic precipitation zone on the West Coast of the South Island of New Zealand. Rainfall exceeds 6000 mm/year and arrives with frequent flood events that can deliver > 200 mm/day. Streams vary in discharges by up to two orders of magnitude over a time scale of hours. Pyritic waste rock at the mine interacts chemically with even the most intense rainfall, and almost all runoff is acidic to some degree. In the most intense rain event recorded in this study (> 10 mm/hour), dilution of acid mine drainage (AMD) occurred and pH rose from 3 to > 5 over several hours, with stream discharge at a monitoring point rising from < 0.5 to > 100 cumecs. However, most rain events of similar magnitude are less intense, longer duration, and only raise AMD pH to ~ 4 with similar high discharges. Results presented here for Stockton confirm that it is the intensity of rain events on the hourly scale, rather than the total amount of rainwater delivered to the site, that governs the amount and composition of AMD generated during flood events. Stream discharge loads of dissolved iron and aluminium range from ~ 20 to 1000 kg/hour. Dissolved sulfate and acidity loads are typically ~ 500 kg/hour but can exceed 20 tonnes/hour in rain events.First flush effects observable elsewhere around the world involving peak metal loads following dry periods or seasonal changes are not obvious at Stockton due to the high and variable rainfall environment. Dissolved Fe concentrations may be limited in runoff waters by precipitation of jarosite and schwertmannite, especially when rainfall is sufficiently intense to raise pH to 4 or higher. These minerals are widespread in the exposed waste rock on site. Likewise, precipitation of alunite may occur as pH rises in rain events, but no field evidence for this has been observed. 相似文献
9.
Corina Buckenberger 《Journal of Housing and the Built Environment》2012,27(1):69-88
Housing research has mostly addressed notions of housing qualities either from a quantitative approach or through the provision
and availability of housing. The literature has predominantly focused on physical structures, often neglecting residents’
experiences of the built environment. Including individuals’ perceptions of their dwelling environment can add insights valuable
to planning and design efforts which are aimed at providing good ‘quality’ and need to be taken into account in concepts of
housing quality. The present study considers the housing qualities of a suburban built environment as psychological and socio-cultural
aspects that are experienced by residents. Owner-occupants’ perceptions of housing quality are illustrated through the use
of ‘tag clouds’ that represent visual dwelling-quality profiles. They highlight which attributes of the occupants’ living
environment are meaningful to them and how they achieve a greater sense of belonging in the dwelling as well as in the neighbourhood.
This paper draws on results from in-depth interviews and brainstorming about housing qualities with 19 owner-occupants in
the suburb of Farm Cove in Manukau City in the Auckland Region, New Zealand. Two predominant age groups were identified in
this case study: the elderly long-term residents who moved to the area in the 1970s during the time of suburbanization; and
families in their thirties and early forties who moved to the area in recent years. The paper reveals a shift in experienced
housing qualities from tangible among the younger cohort towards more intangible qualities among the elderly. An assessment
of the findings suggests a need for future planning which caters for more heterogeneous housing qualities. 相似文献
10.
Twelve polynuclear aromatic hydrocarbons (PAH) were evaluated by chromatographic procedures using a HPLC-UV detector and a GC-FID detector. The PAH were evaluated in airborne particulate matter collected in La Plata, Argentina, over a period of 2 years (with sampling periods of approximately 4 months). The samples were size fractionated, and the PAH in each fraction determined. The analytical procedure used was as follows: extraction in benzene, concentration at room temperature, clean-up in a silica gel column and, finally, evaluation by chromatographic procedures. The extraction recovery was 76.2 +/- 5.8% for naphthalene and 96.0 +/- 6.2% for chrysene. Clean-up recovery was 87.8 +/- 7.15% for phenanthrene and 98.1 +/- 8.3% for anthracene. The largest PAH load was present in the smallest fractions. The smallest particles were carbonaceous in nature. The concentration peak was associated both with the total mass of airborne particulate matter and the reduction in amounts of coarse particles. The PAH distribution could not be correlated with characteristic physicochemical properties such as water solubility or the octanol-water distribution coefficient. The PAH load was greater in fall and winter than in spring and summer. This could be attributed to the reduction of photochemical processes during the cold seasons. 相似文献
11.
Jenny McArthur 《Urban Policy and Research》2019,37(1):45-61
Expert technical knowledge has a central role in decision-making for urban transport and is subject to public scrutiny for major investments. This paper examines how expertise is produced and contested by advocacy groups in Auckland, New Zealand. A network of advocates has emerged, garnering considerable influence as “experts” on urban transport and planning. In response to the perceived over-reliance on outdated approaches to transport, advocates mobilised alternative expertise using blogs and social media. Internet platforms enabled groups to extend the public sphere online, creating spaces for deliberation and contestation. Their activities targeted the technocratic logics embedded in forecasting models, reasserted transport infrastructure’s function as urban space, and highlighted how transport infrastructure shapes everyday experience. This case shows how advocates countered the postpolitical condition by re-ordering the polity of transport in Auckland. Advocates have been instrumental in appropriating globally mobile policies and successfully promoted improvements to public transport and cycling. However, those interviewed showed limited consideration of equity issues related to income, race and gender. This raises questions over whether the expertise mobilised favoured privileged groups, as advocates may be unaware of marginalisation that they rarely experience themselves. Alliances with community groups and local researchers can support broader engagement with distributional issues. 相似文献
12.
Airborne particulate matter was sampled near the Cosmic Ray Laboratory of Chacaltaya, Bolivia, about 25 km NE of La Paz, at an altitude of 5200 m.Quantitative analysis of organic compounds was performed on two combined samples by gas chromatography-mass spectrometry with computerized data acquisition. Results are presented for aliphatic and polyaromatic hydrocarbons, fatty acids and heterocyclic arenes.A comparison is made with the results obtained from samples collected in a residential city area of Antwerp, Belgium. Polyaromatic hydrocarbons are found to be present in lower concentrations in the Bolivian samples by a factor of 10 to 300. For other compounds no meaningful differences are observed. The amount of the total suspended particulate matter per unit of volume is about three times lower in the remote area compared to the residential area. 相似文献
13.
Suspended particulate matter (SPM), sampled from the stack of a large refuse incinerator in the U.K., contained markedly elevated levels of Cd (approximately 1600 micrograms g-1) and Pb (approximately 3%). These values were similar to those previously reported for several other incinerators in Europe, but the Pb concentrations were lower than in the SPM from three American incinerators. Calculation of the metal concentration ratio SPM/fly ash for the U.K. incinerator revealed a three-fold enrichment of the two metals on the SPM. Similar ratios were obtained for several other European incinerators; this correspondence in metal partitioning was linked to the use of electrostatic precipitators in these facilities. The SPM metal data obtained in this study were used to estimate atmospheric emissions of 0.5 t Cd year-1 and 11 t Pb year-1 from the incinerator. Extrapolation of the Cd and Pb emission factors derived from this study to the quantity of refuse incinerated in the U.K. results in atmospheric discharges of 6 t Cd year-1 and 115 t Pb year-1. These estimates are in good agreement with those previously reported by an emissions inventory which identified incineration as the single largest source of airborne Cd in the U.K. 相似文献
14.
Solid state partitioning of trace metals in suspended particulate matter from a river system affected by smelting-waste drainage 总被引:1,自引:0,他引:1
The partitioning of particulate trace metals was investigated during one year of monthly sampling of suspended particulate matter (SPM) at eight sites along the Lot-Garonne fluvial system, known for its polymetallic pollution. The chemical partitioning in five operationally defined fractions (exchangeable/carbonate, Fe/Mn oxides, organic matter/sulfides, acid soluble, residual) was determined using a multiple single extraction approach. This approach showed that Cd, Zn, Pb and Cu were mainly associated with acid soluble phases (84-95%, 65-88%, 61-82% and 55-80% of the respective total metal content), and therefore showed a high mean potential of mobilization and bioavailability. In the Riou-Mort River, draining the smelting-wastes, Zn, Cd and Mn showed high mobility as they were little associated with the residual fraction (1-2%) and mainly bound to the 'exchangeable' fraction of SPM (60-80%), probably weakly adsorbed on amorphous freshly-precipitated sulfide and/or oxide phases. Upstream and downstream of the anthropogenic source of metallic pollution, Mn and Cd, and Zn to a lesser extent, remained highly reactive. The other trace metals were mainly associated with the residual fraction and thus less mobile. However, the multiple single extraction scheme revealed that the most reactive transport phases were non-selectively extracted by the conventional extractants used here. These selectivity problems could not have been observed if sequential extraction was used. 相似文献
15.
Cities are largely designed for adults and cars, not children. Auckland City's new ‘children first’ approach signals a shift in policy focus to consider the needs of children. The authors' ‘Kids in the City’ research is helping inform this approach by providing policy-relevant information about children's use and experiences of nine Auckland neighbourhoods, suburban and inner-city, using trip diaries, child-led walk-along interviews and discussion groups. The children were neighbourhood key informants and co-producers of knowledge who reported on their environments, discussed what they liked and disliked, their safety concerns and their limited mobility, and made suggestions for more ‘child-friendly’ neighbourhoods. 相似文献
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F Valerio C Brescianini A Mazzucotelli R Frache 《The Science of the total environment》1988,71(3):501-509
In November 1985 a research program started, with the aim to evaluate seasonal variations in the concentrations of organic and inorganic pollutants in the atmosphere of Genoa. The program provided for the collection of samples of airborne particulate in five different areas with distinct urban characteristics. First results for chromium, lead, and thallium concentrations in an industrial and in an urban area are reported. Lead showed the highest concentration at both locations (geometric mean: 1.037 and 0.476 microgram/m3, respectively) and appeared to be little affected by seasonal variation. Private traffic was confirmed as the main source of this pollutant. Chromium and thallium geometric mean concentrations were 0.006 and 0.014 microgram/m3 in site A and 0.017 and 0.015 microgram/m3 in site B, respectively. In the urban location a good negative linear correlation was found between chromium and thallium concentration and mean ambient temperature; the domestic heating plants were suspected as important emission sources of these two compounds. 相似文献
17.
Urban runoff is a resource for reuse water. However, runoff transports indicator and pathogenic organisms which are mobilized from sources of fecal contamination. These organisms are entrained with particulate matter (PM) that can serve as a mobile substrate for these organisms. Within a framework of additional treatment for reuse of treated runoff which requires the management of PM inventories in unit operations and drainage systems there is a need to characterize organism distributions on PM and the disinfection potential thereof. This study quantifies total coliform, Escherichia coli, fecal streptococcus, and enterococcus generated from 25 runoff events. With the ubiquity and hetero-dispersivity of PM in urban runoff this study examines organism distributions for suspended, settleable and sediment PM fractions differentiated based on PM size and transport functionality. Hypochlorite is applied in batch to elaborate inactivation of PM-associated organisms for each PM fraction. Results indicate that urban runoff bacterial loadings of indicator organisms exceed U.S. wastewater reuse, recreational contact, and Australian runoff reuse criteria as comparative metrics. All monitored events exceeded the Australian runoff reuse criteria for E. coli in non-potable residential and unrestricted access systems. In PM-differentiated events, bacteriological mobilization primarily occurred in the suspended PM fraction. However, sediment PM shielded PM-associated coliforms at all hypochlorite doses, whereas suspended and settleable PM fractions provide less shielding resulting in higher inactivation by hypochlorite. 相似文献
18.
Trace element and Sigma DDT concentrations in horticultural soils from the Tasman, Waikato and Auckland regions of New Zealand 总被引:1,自引:0,他引:1
Gaw SK Wilkins AL Kim ND Palmer GT Robinson P 《The Science of the total environment》2006,355(1-3):31-47
The long-term routine use of agrichemicals can result in elevated levels of trace elements and persistent organic pollutants in soils. Trace element concentrations and SigmaDDT levels were measured in soil (0-7.5 cm) samples collected from horticultural and grazing properties in 3 regions of New Zealand (Auckland, Tasman and Waikato). Elevated levels of arsenic (<2 to 58 mg kg(-1)), cadmium (<0.1 to 1.5 mg kg(-1)), copper (5 to 523 mg kg(-1)), lead (5 to 243 mg kg(-1)) and SigmaDDT (<0.03 to 34.5 mg kg(-1)) were detected in soils from all 3 regions. With the exception of cadmium and zinc, significantly higher levels of contaminants were generally detected in horticultural soils than in grazing soils. Our results have implications for the on-going use of agrichemicals as concentrations of cadmium, copper, tin and zinc in some samples exceeded ecotoxicity based soil criteria. The p,p'-DDE:DDT ratios indicate that the degradation of DDT in NZ horticultural soils may be inhibited by the co-contamination with trace elements. 相似文献
19.
Cassoni F Bocchi C Martino A Pinto G Fontana F Buschini A 《The Science of the total environment》2004,324(1-3):79-90
ARPA Emilia Romagna created, in 1997, a regional network for the continuous monitoring of the mutagenicity of PM(2.5) by short-term mutagenicity bioassays to guarantee a constant surveillance on the entire regional territory. The continuous monitoring of the PM mutagenicity provides essential information for a better understanding of the impact of air pollution on the health of the population, and allows one to better judge the efficiency of national and local efforts for urban air quality improvement (use of "green" petrol and ecodiesel, days during which traffic is prohibited, etc.). This article presents the results relating to the Network's activity between September 2000 and December 2002, on PM(2.5) fraction. The organic extracts of PM(2.5) were tested for mutagenicity using Salmonella tester strains TA98 and TA100 with and without metabolic activation (S9). The data obtained on the genotoxicity of air particulate extracts have revealed a constant presence of mutagenic substances adsorbed on particulate matter-with a prevalence of direct-acting mutagens than of promutagens-in a typical seasonal trend featuring higher levels in autumn-winter and lower in warmer periods of the year. In this work the evolution of PM(2.5) mutagenicity was compared with the particles, carbon monoxide (CO) and nitrogen dioxide (NO(2)) concentrations (monthly average); these comparisons revealed a quite good level of agreement on a local basis. 相似文献
20.
《Journal of Urbanism》2013,6(4):406-422
Temporary uses of vacant urban spaces are usually not foreseen in conventional urban planning and have often been linked to economic or political disturbances. In New Zealand, Christchurch’s vacant spaces came into existence after the city was hit by several devastating earthquakes in 2010 and 2011. Parallel to the ‘official’ rebuild discourse, temporary uses have emerged on vacant post-earthquake sites including community gardens, urban agriculture, art installations, event venues, eateries and cafés, and pocket parks. Based on the review and analysis of exemplary transitional community-initiated open spaces and correlated literature, the paper looks at how the post-disaster urban context in Christchurch has influenced particular aspects of temporary urbanism in comparison with case studies in non-disaster environments. By focusing on the anticipated benefits of community-initiated open spaces, the paper discusses the relevance of temporary uses of vacant urban spaces for urban sustainability in relationship to concepts of community resilience and raises questions about possible long-term values. 相似文献