川东北高含硫气田区域应急管理模式探讨

川东北高含硫气藏安全环保风险问题日益突出。文章通过对川东北高含硫气田应急管理体系现状的全面调研,针对当前勘探开发形势下各气田应急管理主体分散、应急联动体系效力不高、区域应急管理机制尚未健全等突出矛盾问题,提出川东北高含硫气藏区域网络式的动态应急管理模式,为进一步提升当前的应急管理体系的效果提供了理论支持。     

太湖流域农田生产-畜禽养殖系统氮素流动特征

为应对太湖严峻的水体富营养化现状,从源头上降低面源污染负荷,基于物质流分析法与质量守恒原理,研究了常熟市辛庄镇农田生产-畜禽养殖系统的氮素流动通量、流动效率及环境负荷,并用实测值进行了参数校正. 结果表明:2000—2012年,辛庄镇农田生产子系统的单位面积氮素流动通量呈下降趋势,而畜禽养殖子系统的单位面积氮素流动通量则在42.5~50.9 kg/hm2范围内持续波动. 氮素利用率与氮素循环利用率均较低,氮素环境损失率较高,系统损失的氮素中有54.5%进入周围水体. 2000年以来,作物种植与畜禽养殖对辛庄镇环境氮负荷的贡献率分别在38.8%~50.2%与25.4%~35.8%之间波动. 辛庄镇农田施氮量为310.8 kg/hm2,人畜排泄氮量为61.1 kg/hm2,分别远高于全国平均值(197.2和18.6 kg/hm2). 过量施用化学氮肥与畜禽粪便的大量排放是辛庄镇环境氮负荷加重的主要原因. 辛庄镇高投入高产出的农业生产方式加大了太湖水环境修复的难度. 建议调整作物种植与畜禽养殖结构,推广科学施肥与生态养殖,将农田生产与畜禽养殖结合形成产业链,以此减轻氮素环境负荷.      

广州秋季不同功能区大气颗粒物中PAHs粒径分布

利用MOUDI^TM级联分段式采样器采集了秋季广州市区(荔湾采样点和五山采样点)及郊区(新垦采样点)3个采样点的气溶胶样品并使用GC-MS分析了样品中13种多环芳烃的含量.发现3～4环的多环芳烃呈双峰分布,5～7环的多环芳烃呈单峰分布.广州市区和郊区的多环芳烃具有不同粒径分布模式;相对于城区,郊区的多环芳烃存在于更大的颗粒物中,这可能是气溶胶的陈化过程不同导致的.城区的多环芳烃可能主要受吸附作用控制,而郊区的多环芳烃则可能受多种机制控制,如吸附作用、吸收作用和多层吸附.诊断参数值在粒径1～2.5μm和0.1～0.56μm存在较大差异;从浓度上看新垦13种多环芳烃的总浓度为39ng/m³,五山为71～94ng/m³,荔湾为32～154 ng/m³;从组成上看广州市大气颗粒物种多环芳烃以5～7环为主.     

滇池生态安全综合评估研究

湖泊水库的生态安全是湖库区(流)域人民赖以生存和社会经济可持续发展的重要基础.通过深入剖析湖库生态安全的内涵,运用湖库生态安全综合评估模型,从人类活动压力、湖库水体健康和湖库生态服务功能三方面评价了滇池1999~2007年间的生态安全状况.结果表明,通过污染物排放总量的控制,至2007年人类活动对滇池产生的直接压力已有效减轻,然而湖体水质状况却未得以根本改善,多年来滇池生态安全状况处于Ⅳ级,即生态安全状况较差.     

安徽省湖库型饮用水水源地水质评价研究

随着水资源日益紧缺以及水源污染情况的不断加剧,饮用水水源地的水质问题越来越受到社会的关注。运用单因子标准指数法以及卡尔森指数方法时安徽省境内31个县级以上的湖库型饮用水水泺地的水质状况以及湖泊富营养化程度进行了综合评价,并提出相应的防护措施。评价结果表明,全省湖库型饮用水水源地水质迭标个数为27个,达标率为87％。     

澜沧江梯级水坝库区大型底栖动物群落结构及水质生物学评价

梯级水电开发虽然可以最大程度地利用河流的水能资源,但同时也是对河流生态系统的大规模扰动.大型底栖动物被认为是开展梯级水坝水生态系统变化和演替研究的指示生物类群.本文选取澜沧江中下游水电基地为研究区,于2016年开展漫湾和大朝山梯级水坝库区大型底栖动物群落采样调查,分析梯级库区大型底栖动物的群落结构和分布格局,基于生物指数(BI)开展水质生物学评价.结果表明:大型底栖动物物种组成以寡毛纲、软体动物门及昆虫纲的摇蚊类为主,优势种则以软体动物门的河蚬占绝对优势;群落密度和生物量分布格局表现为静水区显著高于过渡区;静水区功能摄食群密度组成以收集者(GC)和滤食者(FC)占优势,生物量组成则以滤食者(FC)占优势;ABC曲线和生物指数分析表明,上游漫湾库区群落稳定性及水质优于下游大朝山库区,反映了梯级水坝沿着河流纵向梯度水环境逐渐变差的趋势,澜沧江梯级水坝库区大型底栖动物群落结构、分布格局和库区水质状况受梯级水坝运行影响表现为明显的累积效应和富营养化效应.     

EFFECTS OF WATER DRAWDOWN ON THE FAUNA IN SMALL COLD WATER RESERVOIRS1

ABSTRACT: Two small cold water reservoirs with stable water levels were compared with two reservoirs scheduled for complete drawdown to determine the effects of drawdown on invertebrate abundance and fish abundance and density. An extensive literature review supplemented the results with other applicable information. No conclusive evidence of effects of drawdown on invertebrates or fish was found. Characteristics of a reservoir and its drainage basin which obscure or lessen drawdown effects are discussed. Analysis and observation of drawdown procedures showed that duration and scheduling of draw-down periods are important in determining whether drawdown will be harmful to fauna in a given reservoir.     

PRELIMINARY DESIGN AND COST ESTIMATING FOR RESERVOIR PROJECTS1

ABSTRACT: In estimating the costs of a reservoir project, it is difficult to produce accurate costs without performing a detailed design and quantity takeoff. The computerized procedure presented in this article provides a method for determining these planning level costs quickly and easily, while maintaining reasonable accuracy.     

THE ECONOMIC FEASIBILITY OF DUAL PURPOSE NUCLEAR DESALINATION OF GROUND WATER1

ABSTRACT: The economic feasibility of a large scale dual purpose (desalting water and power production) facility were evaluated. Although a site in the Tularosa basin of southern New Mexico was chosen as a case study for this analysis, it is believed that the approach and consequential results would be applicable to alternative sites in the Southwest. The basic project evaluated included: a) a ground water well field; b) a dual purpose, nuclear, desalination plant; c) a mineral recovery plant; and d) a reservoir for recreation and irrigation storage. Principle project outputs included electrical power, minerals, recreation, and water for either irrigated agricultural production or export to an adjoining river basin. Two alternative project designs were developed for detailed analysis. The first alternative encompassed all major project components. The results, in discounted net values used to assess the feasibility of the project, were essentially negative; that is, values were less than zero for full scale development. The net benefits ranged from $-986.57 million at a 5 percent discount rate, to $-1,137.528 million at a discount rate of 10 percent. In the second alternative, exportation of the desalted water from the Tularosa basin to two adjacent rivers was analyzed with somewhat better net benefits, ranging from $-382,527 million to $-478,612 million at the 5 and 10 percent discount rates.     

MULTIVARIATE CLASSIFICATION OF SMALL ORDER WATERSHEDS IN THE QUABBIN RESERVOIR BASIN,MASSACHUSEVFS1

ABSTRACT: A multivariate approach was used to analyze hydrologic, geologic, geographic, and water-chemistry data from small order watersheds in the Quabbin Reservoir Basin in central Massachusetts. Eighty three small order watersheds were delineated and landscape attributes defining hydrologic, geologic, and geographic features of the watersheds were compiled from geographic information system data layers. Principal components analysis was used to evaluate 11 chemical constituents collected bi-weekly for 1 year at 15 surface-water stations in order to subdivide the basin into subbasins comprised of watersheds with similar water quality characteristics. Three principal components accounted for about 90 percent of the variance in water chemistry data. The principal components were defined as a biogeochemical variable related to wet. land density, an acid-neutralization variable, and a road-salt variable related to density of primary roads. Three subbasins were identified. Analysis of variance and multiple comparisons of means were used to identify significant differences in stream water chemistry and landscape attributes among subbasins. All stream water constituents were significantly different among subbasins. Multiple regression techniques were used to relate stream water chemistry to landscape attributes. Important differences in landscape attributes were related to wetlands, slope, and soil type.