Application Of Geographical Information System (GIS) To The Study Of Mercury Biogeochemistry In The Environment

Mercury is a global pollutant. From 1950s when Miriamata disease occurred in Japan to the last two decades when mercury concentrations in fish from remote areas of northern America and northern Europe were discovered to be higher than the advisory limit recommended by WHO, mercury pollution in the environment has been an hotspot issue and tremendous efforts have been diverted to understand the global biogeochemical cycle of this metal.Recent advances have demonstrated that the mercury cycle is much morecomplicated than previously realized. A single way is difficult to research the global cycle of mercury. Many researchers know that we can distinctly understand the global cycle of mercury if using many kinds of methods together. With the advancement of computer technique, geographical information system (GIS) is developing rapidly, which can offer user the data which are collected, stored and analyzed from different aspects in a live environment of spatial data management. The user can put forward new cognition and gain scientific conclusions through analyzing all kinds of correlative or incorrelative spatial information.We research application of GIS to the biogeochemical cycle of mercury. There are two main research topics in this thesis, namely,1) Spatial database is the core of geographical information system(GIS). Using geographical information system (GIS),We establish the spatial database about the biogeochemical cycle of mercury in Guizhou Province. This spatial database which develop with MapObjects and VB can offer users neighbor client support, and it is excellent, such as rapidness, handling facility and optimum efficiency. This spatial database can provide a function to manage spatial data-a number of spatial data and attributes data can be stored, digitized, input, browsed, searched, deleted, output etc. It can offer governmental decision-making department many environmental data by which government can decide what they will do next. Meanwhile, the geochemical data of mercury in Guizhou Province can be used for the global people in this spatial database.2) We estimate the flux from soil to air every year in Guiyang. This study quantifiedthe mercury emissions from Guiyang. Area emissions were calculated using Geographic Information System technology, and in situ derived mercury fluxes and those parameters found to statistically be dominant in controlling emissions. The most important controls on emission strengths were found to be Hg concentration in the soils while environmental parameters such as light were found to drive the diel pattern typically observed for mercury emissions. These emissions are an order of magnitude higher than values applied in global models for natural sources. This study, along with other recent work, demonstrates that natural sources may be an important atmospheric mercury source in Guiyang.