Trihalomethane reactivity of water- and sodium hydroxide-extractable organic carbon fractions from peat soils

Certain organic carbon moieties in drinking source waters of the Sacramento-San Joaquin Delta can react with chlorine during disinfection to form potentially carcinogenic and mutagenic trihalomethanes. The properties of reactive organic carbon in Delta waters, particularly those of soil origin, have been poorly understood. This study attempts to characterize trihalomethane reactivity of soil organic carbon from three representative Delta peat soils. Soil organic carbon was extracted from all three soils with either deionized H2O or 0.1 M NaOH and sequentially separated into humic acids, fulvic acids, and nonhumic substances for quantitation of trihalomethane formation potential. Water-extractable organic carbon represented only 0.4 to 0.7% of total soil organic carbon, whereas NaOH extracted 38 to 51% of total soil organic carbon. The sizes and specific trihalomethane formation potential (STHMFP) of individual organic carbon fractions differed with extractants. Fulvic acids were the largest fraction in H2O-extractable organic carbon, whereas humic acids were the largest fraction in NaOH-extractable organic carbon. Among the fractions derived from H2O-extractable carbon, fulvic acids had the greatest specific ultraviolet absorbance and STHMFP and had the majority of reactive organic carbon. Among the fractions from NaOH-extractable organic carbon, humic acids and fulvic acids had similar STHMFP and, thus, were equally reactive. Humic acids were associated with the majority of trihalomethane reactivity of NaOH-extractable organic carbon. The nonhumic substances were less reactive than either humic acids or fulvic acids regardless of extractants. Specific ultraviolet absorbance was not a good predictor of trihalomethane reactivity of organic carbon fractions separated from the soils.     

Aerosol organic nitrogen over the remote Atlantic Ocean

Water soluble organic nitrogen (WSON) has been measured in aerosols collected on three research cruises on the Atlantic Ocean from approximately 55°N to 45°S. Results are interpreted using air mass back trajectories and results for other aerosol components. WSON concentrations range from <1 to ～40 (median 5.6) nmol m^?3 with significant WSON concentrations in both fine (<1 μm) and coarse mode (>1 μm) aerosol. Concentrations of WSON were highest in samples containing Saharan dust, suggesting a locally significant source associated with soil dust. More generally WSON concentrations were highest in air which had recently crossed continental areas. In the whole data set, WSON is well correlated to total soluble nitrogen and represents approximately 25% of total nitrogen. This correlation implies a significant anthropogenic contribution to the organic nitrogen.     

Does the Coase theorem hold in real markets? An application to the negotiations between waterworks and farmers in Denmark

The Coase theorem depends on a number of assumptions, among others, perfect information about each other's payoff function, maximising behaviour and zero transaction costs. An important question is whether the Coase theorem holds for real market transactions when these assumptions are violated. This is the question examined in this paper. We consider the results of Danish waterworks' attempts to establish voluntary cultivation agreements with Danish farmers. A survey of these negotiations shows that the Coase theorem is not robust in the presence of imperfect information, non-maximising behaviour and transaction costs. Thus, negotiations between Danish waterworks and farmers may not be a suitable mechanism to achieve efficiency in the protection of groundwater quality due to violations of the assumptions of the Coase theorem. The use of standard schemes or government intervention (e.g. expropriation) may, under some conditions, be a more effective and cost efficient approach for the protection of vulnerable groundwater resources in Denmark.     

Public Discourses of Climate Change in Hong Kong

The changing political environment in Hong Kong is likely to accelerate the transition in environmental policy discourse. Opportunities for critical public involvement are increasing and new environmental discourses are emerging. Yet, previous social surveys did not explore the range of these discourses and few focused on climate change. The paper outlines the public discourses of climate change in Hong Kong. Using Q-methodology, four distinctive discourses were identified, namely Pure Environmentalism, Political Pragmatism, Popular Optimism, and Fair Rationalism. While the first one is climate-centric, the other three are political or social in nature and do not indicate a clear or coherent climate orientation. This suggests that the climate change concern of the Hong Kong public is not tightly embedded into a coherent narrative of social and institutional transformation. Effective climate change governance and policies require strengthening the link between such concern and the public desires for social and institutional transformation. Bringing together the ongoing social movements and environmental campaigns will be instrumental to nurture an active climate citizenry.     

Arsenic and copper stabilisation in a contaminated soil by coal fly ash and green waste compost

In situ metal stabilisation by amendments has been demonstrated as an appealing low-cost remediation strategy for contaminated soil. This study investigated the short-term leaching behaviour and long-term stability of As and Cu in soil amended with coal fly ash and/or green waste compost. Locally abundant inorganic (limestone and bentonite) and carbonaceous (lignite) resources were also studied for comparison. Column leaching experiments revealed that coal fly ash outperformed limestone and bentonite amendments for As stabilisation. It also maintained the As stability under continuous leaching of acidic solution, which was potentially attributed to high-affinity adsorption, co-precipitation, and pozzolanic reaction of coal fly ash. However, Cu leaching in the column experiments could not be mitigated by any of these inorganic amendments, suggesting the need for co-addition of carbonaceous materials that provides strong chelation with oxygen-containing functional groups for Cu stabilisation. Green waste compost suppressed the Cu leaching more effectively than lignite due to the difference in chemical composition and dissolved organic matter. After 9-month soil incubation, coal fly ash was able to minimise the concentrations of As and Cu in the soil solution without the addition of carbonaceous materials. Nevertheless, leachability tests suggested that the provision of green waste compost and lignite augmented the simultaneous reduction of As and Cu leachability in a fairly aggressive leaching environment. These results highlight the importance of assessing stability and remobilisation of sequestered metals under varying environmental conditions for ensuring a plausible and enduring soil stabilisation.     

Sonographic demonstration of fetal sacrococcygeal teratoma

Six cases of sonographically diagnosed fetal sacrococcygeal teratoma (SCT) are presented and illustrate the variable features of fetal SCT. The sonographic findings assisted the parents and perinatal team in making decisions, and in two of the cases the children survived after elective Cesarean section and prompt neonatal resection of the tumors. None of the patients showed signs of malignant degeneration of the teratoma or metastases. Fetal SCT no longer should be considered a uniformly fatal condition. The literature on sacrococcygeal teratoma detected after birth indicates that the mortality rate is correlated with the degree of extension of the tumor. Therefore, the classification of sonographically diagnosed fetal SCT according to its size and position is important for decisions regarding pregnancy management.     

An environmental impact assessment of the proposal to build a wind farm at Langdon Common in the North Pennines,UK

Summary This paper measures the diversity of environmental impacts inherent within a proposal by the Central Electricity Generating Board (CEGB) to build a demonstration wind farm at Langdon Common in the North Pennines, UK. This assessment was made in April, 1989 in the wake of the European Community Directive on Environmental Impact Assessment (EIA) and its subsequent interpretation within the UK Town and Country Planning (Assessment of Environmental Effects) Regulations (1988).Langdon Common lies within an Area of Outstanding Natural Beauty (AONB) and within a Site of Special Scientific Interest (SSSI). These designations create a contentious choice of site made by the CEGB and the extent of environmental impact is subsequently made more broad. While the conclusions drawn are specific to Langdon Common, the methodology evolved within the project lends itself to further application to other sites in the future. The following Environmental Impact Assessment can, therefore, be seen as a step towards the reconciliation of the acceptable siting of wind turbines in the UK and the capacity of the planning system to regulate such development.This paper by Alex Steele received the Institution of Environmental Sciences award and First Prize for the best undergraduate environmental project in the UK in 1989. Alex Steele graduated from Sunderland Polytechnic in that year and now works as an Environmental Planner for a leading company of Environmental Management Consultants.     

The contribution of reactive carbon emissions from vegetation to the carbon balance of terrestrial ecosystems

From November 1998 to October 2000, measurements of soil respiration were performed on the Spanish plateau for two patches of non-irrigated barley, one managed with conventional tillage (CT) and the other with reduced tillage (RT). Soil CO2 flux showed seasonal variation on both patches, with an increase from March to October, peaking in May, and a decrease during the winter period by a factor of around 2. The mean value for both combined years was 2.03 and 1.70 micromol m(-2) S(-1), in the CT and RT patches, respectively. In order to analyse the influence of RT on soil CO2 flux, two tests were performed. The first one was the Kruskal-Wallis test to compare whether the differences between the medians in both patches were statistically significant. The results obtained revealed statistically significant differences during the second year, at a 85% and 95% significance level, use being made of annual data and that recorded during the period of maximum interest, March-October, respectively. The decrease in soil respiration in the RT patch was around 24%. The second test was aimed at describing and comparing the influence of soil temperature on soil CO2 flux. By using the data of both patches recorded during the first year, an empirical equation on 10-cm soil temperature was fitted and tested on the data corresponding to the second year in each of the patches. Then, a comparison between the medians of the differences between the estimated and observed values was again performed by means of the Kruskal-Wallis test. The over-prediction of the model in the RT patch, statistically significant at a 90% significance level, was roughly 23%, confirming again the decrease in soil respiration one year after this agricultural management practice had been implemented.     

推动中小建筑企业的革新:欧盟的一个案例研究

建筑业是最古老、最重要的工业之一.它提供了庇护,并为许多人类活动提供了物质框架和基础.它使我们得以生存、参加社会活动、利用我们的环境一总之,实现我们的潜力.但是,同时它也限制了我们的潜力,因为它限制了企业、革新、生产力和以及通过解决贫困、社会排斥和气候变化维持增长的能力.本文介绍了欧盟建筑部门的主要特点,探讨了与促进可持续建筑有关的一些问题.重点介绍了中小建筑企业的基本需求以及为满足这些需求而正在采取的措施.欧洲和其他大陆的发达国家可能还有许多东西要向发展中国家的发展途径和项目支持系统学习.