Are experienced people affected by a pre-set default option—Results from a field experiment

The objective of the present paper is to investigate the robustness of the well-known result that pre-set default options determine people's choices. We do so by conducting a field experiment among environmental economists attending a large international conference on environmental economics. The participants were, at the time of registration, randomly allocated to different treatments related to carbon offsetting. What differs from earlier default studies is that our subjects have good knowledge about the good at hand. We investigate whether the choices of these experienced individuals are affected by a pre-set default option, and we also study the effect of a treatment with no pre-set default option. Our results, together with previous findings, indicate that the effect of a default option attenuates with experience.     

三维地理应急系统在含硫气田开发过程中的建设与应用

针对四川复杂地形含硫气田开发过程中可能出现的火灾、爆炸、原料气泄漏等突发事故,难以及时判断事故的发展趋势并确定有效的应对措施,加之对事发点周边的社会和地理环境不熟悉,极易造成群死群伤事故。研究了适用于安全监管与应急防控一体化的管理系统及“平战结合”的运行模式,开发了石油化工领域专用的空间GIS平台,以空间关系做为数据关联分析的底层逻辑,形成贯穿气田设计、建设、运营全生命周期的数据完整性管理体系。并重点针对含硫天然气事故灾害类型和应急支撑数据采集内容进行研究,形成应急管理与快速响应整套技术方法及示范工程,显著缩短了风险辨识和预警时间,提高了应急响应速度和应急决策能力。     

Effects of pollinator density-dependent preferences on field margin visitations in the midst of agricultural monocultures: A modelling approach

Managed field margins offer a means of reducing the impact of agricultural monocultures within intensively managed environments. By providing refuge for wild plants and the pollinators associated with them, field margins can also contribute to enhancing the pollination services within the monoculture. However, the effects of the monoculture on pollinator behaviour need to be carefully considered. It is known that pollinators may show density-dependent preferences such as neophobia (an avoidance of unfamiliar items) when different types of flower are available within their environment, and the dominance of monoculture crops within the environment may consequently have adverse effects upon the preferences shown by pollinators living in the field margins within them. In order to examine how pollinator preferences for wild flowers are affected by monocultures, we modelled the effects of density-dependent preferences, flower densities, and the geometry of field margins within a monoculture landscape using numerical simulations. This was done by considering how the placement of pollinator nests within a simple, spatially explicit landscape consisting of fields of monoculture crops separated by margins containing wild flowers affected the ratio of wild and monoculture crops experienced by the pollinator, given that it could only forage within a limited distance from its nest. Increasing field margin width and decreasing monoculture field width both led to an increase in pollinators visiting wild flowers (which levelled off as width increased). The size of the monoculture fields had little additional effect once they had passed an intermediate width. Increasing wild flower density within the margins led to a shift away from preferring monocultures. When wild flowers were at low densities compared to the monoculture, even the addition of small amounts of extra wild flowers had a large effect in shifting foraging preferences away from the monoculture. The distance which pollinators normally forage over only has an effect upon preferences for wild flowers when the travel distance is small. This suggests that careful consideration of margin design might be extremely important for those species which do not travel far. Innate preferences for density-dependence and particular crop types may also have an effect on preference behaviour. We demonstrate that the way in which resources are presented to indigenous pollinators may be extremely important in influencing where they choose to forage within agricultural landscapes. Careful margin design, as well as increasing the density of wild flowers (such as by enhancing the wild seed bank within the margins), may lead to overall improvements in ecosystem function within intensively farmed monocultures.     

基于油罐火灾数值模拟的模型选取与分析

计算机模拟方法是当今研究油罐火灾发生、发展规律的重要手段。为此 ,从油罐燃烧的特点出发 ,搜集了当前最新的 1 7种火灾模型 ,对比分析了它们的特点和适用范围 ,并筛选出 7种适于模拟油罐火灾的模型 :ALOFT -FT ,FDS ,CFX ,FLUENT ,PHOENICS ,JASMINE和FIRE。通过对这些模型计算方法的进一步比较 ,分析了利用这 7种模型模拟油罐火灾的优点和缺点。最后 ,提出了运用FDS模型模拟油罐火灾的优势 ,并用其进行了计算和分析 ,得到了满意的结果     

Terrestrial perturbation experiments for environmental assessment

The National Environmental Policy Act of 1969 (NEPA) was initially interpreted as requiring full disclosure of the environmental impact of a federal action. Because of the limitations of time, money, and manpower, the requirement that all impacts be considered has led to superficial analysis of many important impacts. Data collection has largely been limited to the enumeration of species because this information can be applied to the analysis of any problem. The President's Council on Environment Quality (CEQ) has provided a solution to this problem by reinterpreting NEPA as requiring analysis of those impacts that have significant bearing on decision making. Because assessment resources can now be concentrated on a few critical issues, it should be possible to perform field perturbation experiments to provide direct evidence of the effects of a specific mixture of pollutants or physical disturbances on the specific receiving ecosystem. Techniques are described for field simulation of gaseous and particulate air pollution, polluted rain, soil pollutants, disturbance of the soil, and disturbance of wildlife. These techniques are discussed in terms of their realism, cost, and the restrictions that they place on the measurement of ecological parameters. Development and use of these field perturbation techniques should greatly improve the accuracy of predictive assessments and further our understanding of ecosystem processes.Research sponsored by the Office of Health and Environmental Research, U.S. Department of Energy, under contract W-7405-eng-26 with Union Carbide Corporation.Publication No. 1816, Environmental Sciences Division, ORNL.     

Monitoring bioaccumulation and toxic e ects of hexachlorobenzene using the polyurethane foam unit method in the microbial communities of the Fuhe River,Wuhan

Hexachlorobenzene （HCB） is a chlorinated aromatic hydrocarbon that was widely used for seed dressing in prevention of fungal growth on crops, and also as a component of fireworks, ammunition, and synthetic rubbers. Because of its resistance to degradation and mobility, HCB is widely distributed throughout the environment and is accumulated through food chains in different ecosystems. In this study, a preliminary investigation was carried out on the bioaccumulation and the toxic effects of HCB in the microbial （protozoan in particular） communities in the Fuhe River, Wuhan, a water body receiving industrial wastewaters containing HCB and other pollutants, using the standardized polyurethane foam units （PFU） method. Field samples were taken from eight stations established along the Fuhe River in January and August 2006. The concentration ratios of HCB in microbial communities and in water were 9.66-18.64, and the microbial communities accumulated 13.29-56.88 μg/L of HCB in January and 0.82-10.25 μg/L HCB in August. Correlation analysis showed a negative correlation between the HCB contents in the microbial assemblage, and the number of species and the diversity index of the protozoan communities. This study demonstrated the applicability of the PFU method in monitoring the effects of HCB on the level of microbial communities.     

利用GMS模拟技术分析矿坑涌水对周围村庄的影响

运用地下水数值模拟技术,通过GMS地下水数值模拟软件对矿区地下水动态进行模拟,对矿坑涌水给矿区周围地下水环境带来的影响进行预测,并通过预测结果说明在环境影响评价中如何应用数值模拟技术分析矿坑涌水对周围村庄的影响。     

王港河流域水环境质量溯源调查分析

以王港河流域为研究对象,根据2016—2020年、2021年1月29日—31日2个时间段的水质历史监测数据、2020年高分遥感影像解译结果和对高锰酸盐指数、化学需氧量、氨氮、总磷指标的加密监测数据及现场核查,对王港河流域水环境质量范围进行了溯源调查分析。结果表明,2016—2020年,王港河流域水质逐年好转;遥感解译共289个工业企业地块,102个水产养殖地块,169个畜禽养殖地块,92个疑似污染水体地块;王港河流域上游水质明显好于下游,下游沿线支流水质较差,畜禽养殖污染占比较高,是影响水质的主要原因,此外,沿河乡镇生活污水和工业污水收集处理效率低,以及工业园区工业污染源、农场农田退水、水产养殖排水也是影响水质的重要原因。     

兴盐界河民主村断面水环境质量溯源调查分析

以民主村断面上游为研究对象，利用有机物非靶向筛查技术，结合现场快速筛查、实验室分析及现场实地勘查结果，判断重点监测区域污染情况，并使用卫星遥感、无人机及现场排查对民主村断面所在的兴盐界河开展全流域排查。结果表明，兴盐界河沿线排污口众多，民主村断面汇水区域及兴盐界河沿线广泛受到养殖业、生活源、种植业污染，河内源污染严重，加之水流不畅、汛期放大污染等自然因素，导致断面水质无法稳定达标，全年平均水质超Ⅲ类。