The Axford Debate Revisited: A Case Study Illustrating Different Approaches to the Aggregation of Benefits Data

Recent debate following the rejection of the Environment Agency case regarding an application for water abstraction at Axford on the River Kennet has focused upon the benefits procedure employed for aggregating non-user benefits which underpinned the economic case put forward by the Agency (although this was not the reason cited by the inquiry for rejection of the case). Commentators have seen this case as setting an unfortunate precedent for the use of economic assessments in such resource management issues. The paper presents a number of highly tractable alternative methods for the aggregation of benefits estimates designed to address the central problems of the definition of a relevant aggregation population and a potential decay of values with increasing distance from a given valuation site. These methods are tested using data obtained from a national survey of non-users of a specific natural area. Results from this application indicate that simpler approaches such as that used at the Axford inquiry may result in aggregate benefits estimates which are very substantially larger than those produced by our proposed alternative approaches to aggregation.     

科学的监督机制胜于频繁的安全检查

现在到企业特别是高危企业生产现场检查最多的是哪类人员？我的感觉是安全监管类官员。君不见电视上经常播出政府领导深入企业一线检查安全工作的画面吗？政府官员不是专业安全从业人员，对比较专业的安全知识了解得不是很详细，再加上岗位的变动性，     

Assessment of two thermally treated drill mud wastes for landfill containment applications.

Offshore oil and gas drilling operations generate significant amounts of drill mud waste, some of which is transported onshore for subsequent thermal treatment (i.e. via thermal remediation). This treatment process results in a mineral waste by-product (referred to as thermally treated drill mud waste; TTDMW). Bentonites are originally present in many of the drill mud products and it is hypothesized that TTDMW can be utilized in landfill containment applications (i.e. cover or base liner). The objective of this paper is to examine the feasibility of this application by performing various physical and chemical tests on two TTDMW samples. It is shown that the two TTDMW samples contained relatively small amounts of clay-sized minerals although hydraulic conductivity values are found to be less than 10(-8) m/s. Organic carbon contents of the samples were approximately 2%. Mineralogy characterization of the samples confirmed varying amounts of smectite, however, peak friction angles for a TTDMW sample was greater than 36 degrees. Chemical characterization of the TTDMW samples show potential leaching of barium and small amounts of other heavy metals. Discussion is provided in the paper on suggestions to assist in overcoming regulatory issues associated with utilization of TTDMW in landfill containment applications.     

两种底质对狐尾藻生长和生理指标的影响

在温室条件下,分别以土壤和沉积物作为底质,模拟研究狐尾藻（Myriophyllum spicatum）生长和生理指标的变化。结果表明：与营养水平相当的沉积物相比,以土壤作为底质的处理,其狐尾藻茎叶生物量降低了87．15％,根系生物量增加了226．54％,根系活力降低了46．46％,超氧化物歧化酶（SOD）和过氧化物酶（POD）活性分别增加了134．20％和119．91％。上覆水和间隙水中活性磷浓度分别增加了146．67％和1382．61％。以土壤为底质,增加该处理水体中磷浓度,抑制狐尾藻生长。     

氯仿作为抑制剂对沉积物-水系统中氮转化的影响

氯仿是土壤的营养物释放实验中常用的微生物活性抑制剂。文章探讨了在滇池沉积物-自配水系统中投加氯仿后系统中上覆水的氮质量浓度变化(上覆水初始质量浓度:总氮15.0mg·L-1,氨氮7.5mg·L-1,硝氮7.5mg·L-1)以及沉积物中的硝化和反硝化活性的变化。结果表明,实验过程中上覆水的总氮、氨氮和有机氮的质量浓度升高,硝氮的质量浓度降低,加氯仿组和未加氯仿组的总氮分别升高35.9%和46.9%。这是因为实验过程中硝化速率降低而反硝化速率升高导致的。加抑制剂组的上覆水中的总氮和氨氮质量浓度总体上高,硝氮和有机氮总体上低,说明氯仿对硝化反应的抑制作用持续到第816h,在最初和后期抑制作用更显著。加氯仿组的pH值明显高于未加氯仿组,DO质量浓度稍高于未加氯仿组。实验结束后,加氯仿组的沉积物的硝化速率和反硝化速率略低于未加氯仿组的。氯仿在沉积物-水系统中起到一定的抑制作用,使沉积物的硝化速率和反硝化速率均降低,但是硝化反硝化活性并未彻底地被抑制;而且抑制具有一定的时效性。     

南宁市南湖沉积物磷释放的研究

采用室内试验模拟法对南宁市南湖沉积物进行磷的释放研究，测定南湖沉积物中磷释放速率及释放量，对影响南湖沉积物磷释放的各种环境因子进行研究。