放射性废金属熔炼去污分配系数研究

放射性污染金属熔炼去污后循环再利用是处理放射性污染金属的有效手段。为了确保熔炼污染物的排放符合国家标准,合理估算释放源项,需要对放射性废金属熔炼去污分配系数进行研究。经对国外金属熔炼设施的分配系数的比较、分析,推荐了一套适用于评价放射性废金属熔炼设施辐射影响采用的核素去污分配系数。     

核与辐射安全监管大数据平台建设策略研究

核能与核技术利用事业的快速发展为我国经济社会发展提供了强大的助推力,但也使得我国面临的核与辐射安全风险日益加大,对核与辐射安全监管的需求与日俱增。当前,我国核与辐射安全监管工作挑战与机遇并存。介绍了我国核与辐射安全监管工作开展现状,分析了其中存在的困难与问题,提出亟需利用信息化及大数据技术,推动我国核与辐射安全监管现代化进程。基于我国核与辐射安全监管数据现状,提出了促进我国核与辐射安全监管数据管理水平提升的几点措施,包括完善数据管理体制,提升数据管理技术,转变数据管理思维,树立数据共享意识等。此外,详细阐述了核与辐射安全监管大数据建设策略,包括总体架构、建设目标、主要任务等。     

浅谈重离子加速器应用放射性污染防治措施

针对重离子加速器运行过程中产生的各类放射性污染物,从辐射防护措施、放射性废物治理措施、辐射安全措施和辐射防护监测4个方面分别进行了放射性污染防治措施的讨论。得出只要严格实施了各项放射性污染防治措施的要求后,放射性工作人员及公众的人身安全是可以保证的,辐射区域周围的环境是安全的。同时,也为辐射环境管理提供了科学依据。     

城市放射性废物库运行安全管理浅议

随着核技术在工业、医疗、探矿、科研等诸多领域的广泛应用和人们对放射性危害认识的提高,废旧放射源和放射性废物逐渐被人们所关注,城市放射性废物库是一个地区重要的放射性污染防治设施,它的安全与否,直接关系到人民群众的身体健康和辐射环境安全。本文介绍了青海省城市放射性废物库基本情况和安全管理做法,并就如何加强城市放射性废物库安全运行管理提出了建议。     

四川省野外探伤的辐射安全现状与对策

本文对四川省的野外探伤单位探伤作业的辐射安全现状进行了调查,分析了野外探伤作业过程中存在的辐射安全问题,提出了野外探伤作业辐射安全监管对策与措施。     

新疆某区域矿产资源开发放射性水平调查与评价

为加强对新疆某区域矿产资源开发过程中的辐射安全监管,通过对该区域52家矿产资源开发企业的γ辐射剂量率进行监测,对超出"当地本底水平+50 nGy/h"的2家企业进行了采样,调查和测量了固体样品中放射性核素含量和水中放射性核素含量,估算了矿产企业工作人员所受年有效剂量。监测结果表明:大部分企业的γ辐射剂量率处在新疆及全国环境本底水平,2家企业处于全疆范围内的γ辐射剂量率的波动范围之外;其中1家企业的固体样品中放射性核素含量异常;水中放射性核素含量均处于全国环境本底水平。2家企业的工作人员所受年有效剂量分别为0.35 mSv和0.75 mSv。评价结果表明:该区域2家矿产资源开发企业存在放射性问题,需加强该区域的辐射安全监管工作。     

对吉林省困难企业放射性废物（源）管理现状及安全管理对策

在全面调查吉林省困难企业放射性废物(源)管理现状的基础上，通过吉林省辐射环境管理部门近年来对放射性废物的管理经验，分析总结了一系列的放射性废物(源)收贮对策，以保证辐射环境安全，杜绝放射性污染事故的发生。     

全省各地环保部门加强汛期环境安全工作

为防范和应对汛期次生突发环境事件,我省近日下发了《进一步加强汛期环境安全管理工作的紧急通知》,要求各地环保部门通过加强环境风险源企业的监管、加强污染防治设施的监管、加强监测预警工作、加强突发环境事件应对准备、加强环境应急工作责任落实等措施确保汛期环境安全。全省各地环保部门根据《通知》要求,     

国际石油和化工公司场地污染防治经验之借鉴

在简要分析我国石油场地污染特征及所面临形势的基础上,调研了国际典型石油污染事故事件,调查总结了BP、壳牌、埃克森美孚、杜邦公司等国际大型石油和化工企业在场地污染防治方面采取的管理措施。综合上述分析,从加强配套管理和技术机构建设、加强场地环境保护能力建设、加强制度和标准体系建设、加强全生命周期场地环境管理、建立企业场地污染防控资金保障机制等7方面,提出国际石油公司在场地污染防治方面的教训和经验对我国石油企业的借鉴建议,对我国石油行业加强场地污染防控和调查修复工作具有指导作用。     

青海省辐射环境监测现状及发展对策的思考

辐射环境监测是核与辐射环境安全监管的重要技术支撑。本文从青海省辐射环境监测能力建设现状和工作开展的实际情况,分析了目前存在的问题,提出了改进措施和对策,对今后的发展提出了几点思考建议。     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.     

Neighbourhood characteristics and urban gardens in the Toledo metropolitan area: staffing and voluntarism,food production,infrastructure, and sustainability practices

Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Predicting deer-vehicle collisions in an urban area

Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.     

MANGANESE CYCLE IN IMPOUNDMENT WATER

Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.     

Biodiversity and biotechnology

The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.     

Surface applied water treatment residuals affect bioavailable phosphorus losses in Florida sands

Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.     

Sources and Transport of Phosphorus to Rivers in California and Adjacent States,U.S., as Determined by SPARROW Modeling

The SPARROW (SPAtially Referenced Regression on Watershed attributes) model was used to simulate annual phosphorus loads and concentrations in unmonitored stream reaches in California, U.S., and portions of Nevada and Oregon. The model was calibrated using de‐trended streamflow and phosphorus concentration data at 80 locations. The model explained 91% of the variability in loads and 51% of the variability in yields for a base year of 2002. Point sources, geological background, and cultivated land were significant sources. Variables used to explain delivery of phosphorus from land to water were precipitation and soil clay content. Aquatic loss of phosphorus was significant in streams of all sizes, with the greatest decay predicted in small‐ and intermediate‐sized streams. Geological sources, including volcanic rocks and shales, were the principal control on concentrations and loads in many regions. Some localized formations such as the Monterey shale of southern California are important sources of phosphorus and may contribute to elevated stream concentrations. Many of the larger point source facilities were located in downstream areas, near the ocean, and do not affect inland streams except for a few locations. Large areas of cultivated land result in phosphorus load increases, but do not necessarily increase the loads above those of geological background in some cases because of local hydrology, which limits the potential of phosphorus transport from land to streams.