福建龙岩可持续发展实验区规划探讨及实践

可持续发展实验区总体规划是区域规划的一种特殊类型。通过对可持续发展实验区及其总体规划的理解和认识,文章指出地方可持续发展实验区总体规划的编制思路应当回归到问题指向型的出发点上来。规划编制思路应当紧密结合宏观经济发展环境、社会事业新要求以及全球环境变化压力等背景,从地区人地关系的突出问题入手,制定实验区可持续发展战略,并通过重点项目落实到规划实施中,使可持续发展实验区总体规划体现实验、探索、示范、创新的作用。文章以福建龙岩可持续发展实验区总体规划编制的实践经验为例,对规划编制思路进行探讨。     

Evaluation of surface runoff and road dust as sources of nitrogen using nitrate isotopic composition

Stable nitrogen and oxygen isotope ratios of nitrate (δ¹⁵N-NO₃ and δ¹⁸O-NO₃) have recently been used to identify nitrogen sources in water environments. However, there have been no investigations designed to determine nitrate isotopes in non-point sources in urban areas for evaluating the impact of surface deposits on nitrogen in surface runoff. In this study, we collected rainwater, surface runoff and surface deposits (road dust, roof dust and soil) to evaluate the nitrogen sources in surface runoff using nitrate isotopes. There were no large differences in δ¹⁵N-NO₃ among rainwater (−0.3‰ to 1.5‰), surface runoff (−2.7‰ to 0.4‰), leachates from road dust (−5.8‰ to 6.2‰) and soil (−11.5‰ to 0.6‰). In contrast, the δ¹⁸O-NO₃ in surface runoff (28.5-47.9‰) was lower than that in rainwater (62.7-78.6‰), and higher than that in leachates from road dust (6.1-27.6‰) and soil (−1.1‰ to 6.6‰). δ¹⁸O-NO₃ is a useful indicator for evaluating the NO₃-N sources in surface runoff. Using this indicator, NO₃-N from road dust was estimated to account for more than half of the NO₃-N in surface runoff. This is consistent with a result based on a comparison of their loads per unit surface between rainwater and surface runoff, which also showed that most of the nitrogen in surface runoff was derived from surface deposits.     

Organochlorines, brominated flame retardants and mercury levels in six seabird species from the Gulf of St. Lawrence (Canada): Relationships with feeding ecology, migration and molt

Concentrations of organochlorines (OCs), brominated flame retardants (BFRs) and mercury (Hg) were measured in eggs of six seabird species breeding in the Gulf of St. Lawrence, Canada. Stable nitrogen (δ¹⁵N) and carbon (δ¹³C) isotopes were used as ecological tracers to measure trophic level and connectivity with benthos, respectively. Concentrations, patterns as well as ecological tracers varied significantly between species. The sum of polychlorinated biphenyls (ΣPCBs) was the most important group measured in all seabird species based on concentration followed generally by the sum of chlorinated pesticides (ΣCPs), the sum of brominated flame retardants (ΣBFRs) and finally total Hg (THg). ΣPCBs, ΣCPs and ΣBFRs increased with trophic level, whereas THg did not. Only ΣBFRs increased with a higher connectivity with the benthos. Seabird species resident to the Great Lakes-St. Lawrence ecosystem showed higher Hg and BFR levels than migratory species. Molt patterns were used to explain variations of contaminant levels.     

Investigating household preferences for kerbside recycling services in London: a choice experiment approach

Recent developments in national and European Union waste management policy have prompted considerable interest in alternative waste management programs, such as recycling, which could divert a portion of the municipal solid waste stream from landfills. This paper examines household preferences for kerbside recycling services and uses a stated preference choice experiment method to estimate households' valuation of such services. Using a sample of 188 households in the London area, the empirical analysis yields estimates of the willingness to pay for the number of 'dry' materials collected, the collection of compost, textile collection and the frequency of collection.     

Atmospheric transport of urban-derived NH(x): Evidence from nitrogen concentration and delta(15)N in epilithic mosses at Guiyang, SW China

Nitrogen concentration and δ¹⁵N in 175 epilithic moss samples were investigated along four directions from urban to rural sites in Guiyang, SW China. The spatial variations of moss N concentration and δ¹⁵N revealed that atmospheric N deposition is dominated by NH_x-N from two major sources (urban sewage NH₃ and agricultural NH₃), the deposition of urban-derived NH_x followed a point source pattern characterized by an exponential decline with distance from the urban center, while the agricultural-derived NH_x was shown to be a non-point source. The relationship between moss N concentration and distance (y = 1.5e^−0.13x + 1.26) indicated that the maximum transporting distance of urban-derived NH_x averaged 41 km from the urban center, and it could be determined from the relationship between moss δ¹⁵N and distance [y = 2.54 ln(x) − 12.227] that urban-derived NH_x was proportionally lower than agricultural-derived NH_x in N deposition at sites beyond 17.2 km from the urban center. Consequently, the variation of urban-derived NH_x with distance from the urban center could be modeled as y = 56.272e^−0.116x − 0.481 in the Guiyang area.     

具有超压/负压防护功能的急救车防生物污染的安全性试验研究

采用粘质沙雷菌气溶胶,对具有超压/负压防护功能的急救车防生物污染的安全性进行试验考核。分别测试气溶胶发生后30s,1min,5min,10min时,车厢在超压防护和负压防护下的过滤效率,其结果表明:急救车在超压防护状态下开启空调时的平均过滤效率能达到99.99%,不开空调时的平均过滤效率能达到99.95%;在负压防护状态下开启空调时的平均过滤效率能达到99.93%,不开空调时的平均过滤效率能达到99.95%。证明急救车能够通过生物污染区域安全运送、急救伤病员,也能够运送、急救生物污染伤病员或烈性传染病员确保沿途环境不受污染,该研究成果为应对生物恐怖袭击和突发公共卫生事件(烈性传染病)提供了一种安全可靠的机动医疗救治平台。     

Public values for badgers,bovine TB reduction and management strategies

This paper applies an attribute-based stated choice experiment approach to estimate the value that society places on changes to the size of the badger population in England and Wales. The study was undertaken in the context of a rising incidence of bovine tuberculosis (bTB) in cattle and the government's review of current bTB control policy. This review includes consideration of culling badgers to reduce bTB in cattle, since badgers are thought to be an important wildlife reservoir for the disease. The design of the CE involved four attributes (size of badger population, cattle slaughtered due to bTB, badger management strategy and household tax) at four levels with eight choice sets of two alternatives presented to respondents. Telephone interviews were undertaken with over 400 respondents, which elicited their attitudes and preferences concerning badgers, bTB in cattle and badger management strategies. The study estimated a willingness to pay of £0.10 per household per year per 100,000 badgers and £1.52 per household per year per 10,000 cattle slaughtered due to bTB which aggregated to £22 per badger and £3298 per bTB slaughtered animal for all households in England and Wales. Management strategy toward badgers had a very high valuation, highlighting the emotive issue of badger culling for respondents and the importance of government policy towards badgers.     

Uranium removal from groundwater via in situ biostimulation: Field-scale modeling of transport and biological processes

During 2002 and 2003, bioremediation experiments in the unconfined aquifer of the Old Rifle UMTRA field site in western Colorado provided evidence for the immobilization of hexavalent uranium in groundwater by iron-reducing Geobacter sp. stimulated by acetate amendment. As the bioavailable Fe(III) terminal electron acceptor was depleted in the zone just downgradient of the acetate injection gallery, sulfate-reducing organisms came to dominate the microbial community. In the present study, we use multicomponent reactive transport modeling to analyze data from the 2002 field experiment to identify the dominant transport and biological processes controlling uranium mobility during biostimulation, and determine field-scale parameters for these modeled processes. The coupled process simulation approach was able to establish a quantitative characterization of the principal flow, transport, and reaction processes based on the 2002 field experiment, that could be applied without modification to describe the 2003 field experiment. Insights gained from this analysis include field-scale estimates of the bioavailable Fe(III) mineral threshold for the onset of sulfate reduction, and rates for the Fe(III), U(VI), and sulfate terminal electron accepting processes.     

北京密云水库流域水体夏季POM浓度及来源分析

为有效控制流域水质污染,保障饮用水水源的水质安全,通过测定北京境内密云水库流域水体夏季悬浮颗粒有机质(POM)的浓度水平及其碳、氮同位素特征,同时以京密引水渠水体为参比,对密云水库汇水流域水体POM的来源进行研究.结果 表明,密云水库流域水体夏季颗粒态有机碳(POC)浓度的变化范围为0.04～0.71 mg/L,平均值...     

Fenton法处理煤气废水的动态实验研究

对Fenton试剂处理煤气废水进行了研究,探讨了Fenton氧化阶段pH、温度、HRT、H2O2投加量、Fe^2＋投加量等因素对COD去除率的影响,确定了最佳处理条件。结果表明,当pH在7．0—7．6范围内,温度为30℃,H2O2投加量为70mL,Fe^2＋投加量为30mL,搅拌60min时,COD去除率在80％以上,处理效果比较好。