射阳县黄沙港流域面源污染现状及防治对策

针对农村面源污染日渐突出的问题,以农村饮用水源地黄沙港为例分析了农村面源污染的现状和成因,并从乡镇规划、生活污水处理工艺选择、畜禽水产业污染治理、农药化肥的施用、农业废弃物利用技术等方面提出防治措施。     

不同收入来源对甘肃省城乡收入差距的影响研究

收入由多个来源部分组成,城乡收入差距的变化是收入来源各部分变动的综合反映,透过收入来源的角度可以清晰地判断城乡收入差距产生的根源.本文运用泰尔指数及其分解方法,对2003-2008年甘肃省城乡收入差距大小及其在总区域收入差距中的贡献变化趋势进行测度,并利用要素分解法实证分析了不同收入来源对城乡收入差距的影响,以此揭示甘肃省城乡收入差距产生的原因.研究发现,城乡收入差距在总区域收入差距中的贡献是递增变化的,已经成为影响甘肃省居民收入差距的重要因素;工资性收入是目前拉大城乡收入差距最为重要的原因,而家庭经营性收入则起着缩小差距的作用,转移性收入和财产性收入在总收入中所占比例很小,但转移性收入对城乡收入差距的贡献却不容轻视.基于研究结果,提出了增加农民非农收入、推进农业产业化进程和完善城乡间收入再分配制度等政策建议,以期为欠发达地区缩小城乡收入差距带来一些启示.     

Point‐Nonpoint Trading – Can It Work?1

Ribaudo, Marc O. and Jessica Gottlieb, 2011. Point‐Nonpoint Trading – Can It Work? Journal of the American Water Resources Association (JAWRA) 47(1):5‐14. DOI: 10.1111/j.1752‐1688.2010.00454.x Abstract: Water quality trading between point and nonpoint sources is of great interest as an alternative to strict command and control regulations on point sources for achieving water quality goals. The expectation is that trading will reduce the costs of water quality protection, and may speed compliance. The United States Environmental Protection Agency has issued guidance to the States on developing point‐nonpoint trading programs, and United States Department of Agriculture is encouraging farmer participation. However, existing point‐nonpoint trading programs have resulted in very few trades. Supply side and demand side impediments seem to be preventing trades from occurring in most trading programs. These include uncertainty over the number of discharge allowances different management practices can produce, high transactions costs of identifying trading partners, baseline requirements that eliminate low‐cost credits, the reluctance of point sources to trade with unfamiliar agents, and the perception of some farmers that entering contracts with regulated point sources leads to greater scrutiny and potential future regulation. Many of these problems can be addressed through research and program design.     

煤矿危险源辨识与多层评价分级研究

根据煤炭系统生产的复杂特点,提出了采用系统科学的方法,对煤炭生产进行系统的单元划分,采用安全系统科学辨识的方法对危险源进行辨识.在此基础上,提出利用层次分析法和模糊动态评判的方法对危险源进行初次分级,根据危险源的耦合特性,提出二次动态分级的方法,对初次分级进行调整,确定危险源科学、合理的级别,并提出了进一步现实性评价的建议.     

Upland Controls on the Hydrological Functioning of Riparian Zones in Glacial Till Valleys of the Midwest1

Abstract: Identifying relationships between landscape hydrogeological setting, riparian hydrological functioning and riparian zone sensitivity to climate and water quality changes is critical in order to best use riparian zones as best management practices in the future. In this study, we investigate water table dynamics, water flow path and the relative importance of precipitation, deep ground water (DG) and seep water as sources of water to a riparian zone in a deeply incised glacial till valley of the Midwest. Data indicate that water table fluctuations are strongly influenced by soil texture and to a lesser extent by upland sediment stratigraphy producing seeps near the slope bottom. The occurrence of till in the upland and at 1.7‐2 m in the riparian zone contributes to maintaining flow parallel to the ground surface at this site. Lateral ground‐water fluxes at this site with a steep topography in the upland (16%) and loam soil near the slope bottom are small (<10 l/d/m stream length) and intermittent. A shift in flow path from a lateral direction to a down valley direction is observed in the summer despite the steep concave topography and the occurrence of seeps at the slope bottom. Principal component and discriminant analysis indicate that riparian water is most similar to seep water throughout the year and that DG originating from imbedded sand and gravel layers in the lower till unit is not a major source of water to riparian zones in this setting. Water quality data and the dependence of the riparian zone for recharge on seep water suggest that sites in this setting may be highly sensitive to changes in precipitation and water quality in the upland in the future. A conceptual framework describing the hydrological functioning of riparian zones on this setting is presented to generalize the finding of this study.     

Contamination of Oxygen-Consuming Organics in the Yellow River of China

Contamination of oxygen-consuming organics (OCOs) was one of the most serious problems in the Yellow River of China. This study was conducted to analyze monitoring of the data on OCOs contamination for the river in 1980 and during 1992–1999 as well as examining the effect of suspended solids (SS) on chemical oxygen demand (COD_Mn) and biochemical oxygen demand (BOD₅) of river water. Several significant results have arisen from the study. First, COD_Mn and BOD₅ of the river water showed an increasing trend from the upper to the lower reaches of the mainstream. BOD₅ values of river water in 1992 were significantly higher than those in 1980 and showed an increasing trend during 1992–1999. Second, OCOs in river water of the mainstream was attributed mainly to point sources; the ratio of point to non-point sources of BOD₅ was about 2.81. The load from point sources showed an increasing trend during 1992–1998. In contrast, the load from non-point sources manifested a decreasing trend during this period; this was caused by the decreasing trend of SS content in river water. The total load of BOD₅ from point and non-point sources displayed an increasing trend during 1992–1998. Third, as the humic substances in SS can hardly be biologically oxidized in natural conditions but can be oxidized by chemical oxidants such as potassium permanganate, COD_Mn was not suitable for being regarded as a parameter reflecting the pollution degree of OCOs in river water with a high SS content.     

基于esp基因和JCV标记的MST方法在五大流域典型水源地中的应用

非点源污染目前已经成为影响水体环境的重要污染。微生物源示踪技术(microbial source tracking,MST)是解决非点源污染的一项新技术,它可以确定污染的宿主来源。肠球菌esp基因和多瘤病毒JCV可以作为检测水体中人源粪便污染的分子标记,其灵敏度和特异性都很高。为分析五大流域水源地是否受到人源粪便的污染,对辽河、海河、淮河、长江和黄河五大流域典型水源地水样进行采集和检测,选取人源粪便特异病原微生物肠球菌的esp基因和多瘤病毒JCV建立了相应的MST分子检测方法。结果表明,五大流域的典型水源地采样点均有可能受到了人源粪便的污染,可为当地相关部门提供技术支持和数据参考。     

水源地污染源分析与保护对策研究

黑河水源地对于保证西安市供水安全具有至关重要的现实意义和长远意义.然而,近年来黑河水库出现水质异常现象,水质有所下降.本文通过对黑河水源地的社会经济和自然环境进行实地调查,分析了水源地的污染源特征,针对性的提出了保护水源地生态环境的对策建议.     

固定源细颗粒物稀释测试法现场应用存在问题及影响因素分析研究

对基于大气环境的稀释测试法在现场应用中存在的主要问题进行了归纳总结,并对若干影响细颗粒物测试结果的重要因素进行了分析,诸如停留时间、稀释比、采样时间等因素,期望能够对该法测试系统的后续改进或重新设计提供实际问题导向,同时也能够对该领域现场工作的科研人员提供非常有用的经验。     

固定污染源烟气比对监测的几点思考

固定源烟气对比监测是保证自动监测数据质量的重要手段。但是,有效性审核比对监测过程中存在烟气排放连续监测系统安装不规范、手工监测抗干扰能力较差、烟气预处理效果不稳定及监测点位差异影响监测结果比对等问题。在此基础上,提出了严格规范环境监测点位的布置,针对不同的污染源确定适合的监测技术方法,研发完善的烟气预处理设施以及建立健全的自动监测质量保证体系等解决问题的对策。