DELAYED GEOCHEMICAL HAZARD: CONCEPT, DIGITAL MODEL AND CASE STUDY
  • 【摘要】

    Delayed Geochemical Hazard (DGH briefly) presents the whole process of a kind of serious ecological and environmental hazard caused by sudden reactivation and sharp release of long-term accumulated po... 展开>>Delayed Geochemical Hazard (DGH briefly) presents the whole process of a kind of serious ecological and environmental hazard caused by sudden reactivation and sharp release of long-term accumulated pollutant from stable species to active ones in soil or sediment system due to the change of physical-chemical conditions (such as temperature, pH, Eh, moisture, the concentrations of organic matters, etc.) or the decrease of environment capacity. The characteristics of DGH are discussed. The process of a typical DGH can be expressed as a nonlinear polynomial. The points where the derivative functions of the first and second orders of the polynomial reach zero, minimum and maximum are keys for risk assessment and harzard pridication.The process and mechanism of the hazard is due to the transform of pollutant among different species principally. The concepts of "total releasable content of pollutant", TRCP, and "total concentration of active specie", TCAS, are necessarily defined to describe the mechanism of DGH. The possibility of the temporal and spatial propagation is discussed. Case study shows that there exists a transform mechanism of "gradual release" and "chain reaction" among the species of the exchangeable and the bounds to carbonate, iron and manganese oxides and organic matter, thus causing the delayed geochemical hazard. 收起<<

  • 【作者】

  • 【作者单位】

    NATIONAL RESEARCH CENTER OF GEOANALYSIS/COLLEGE OF CHEMICAL ENGINEER/LABORATOIRE ENVIRONNEMENT ET MINERALURGIE

  • 【刊期】

    中国科学:地球科学(英文版) EI SCI 2005年z2期

  • 【关键词】

    ENVIRONMENTAL GEOCHEMISTRY  DELAYED GEOCHEMICAL HAZARD  ENVIRONMENTAL CAPACITY  GEOCHEMISTRY  HAZARD  PREDICTION 

  • 【基金项目】

    国家重点基础研究发展计划(973计划)(TG1999045708)