摘要
雨养泥炭沼泽养分补给主要源于大气降水。因为沼泽表面水的流动是缓慢并且有限的,所以沉降至其中的物质依然基本保留在原处。因此,大气颗粒物污染历史在泥炭累积时被保存。在最近20a期间,雨养泥炭沼泽被证明是痕量元素大气沉降富有意义的档案。尤其Pb被广泛深入地研究,并且Pb在泥炭芯中的非迁移性被很好地展示,其它元素也被指明保存在泥炭芯中。国外的泥炭沼泽沉积记录研究在某些方面非常深入细致,前期工作成为后续工作的铺垫,长年的积累形成一定的系统性。利用泥炭沼泽档案,人们对历史时期的环境研究取得了一定成果,尤其在大气金属沉降的泥炭沼泽档案与泥炭地古气候反演方面;但稍显不足的是比较重视对“记录”的研究,而对“机制”的研究深度不够。
According to chemical conditions, peatlands usually defines three types： ① minerotrophic （true fens）, ② ombrotrophic （raised bogs）, and ③ transition （poor fens）. All peatlands, including bogs, develop in waterlogged conditions where dead plants decay slowly because of a lack of oxygen. The result of this in -situ accumulation of organic matter is peat. The rate of decay is so slow that the dead plant remains can resemble the living material even after several thousand years. One type of environmental archive is the peat bog. Peat bogs contain an unparalleled record of our past. A rich archive of information lies preserved in bogs. Much of this is organic, and has a capacity to expand our understanding of people, culture, economy and climate far back into prehistory. the changes The research aim of peat bog archives is the reconstruction of the climate and the climate changesand of the dust and pollutant concentrations in the environment from Holocene to the last hundred years. An ombrotrophic bog is nourished entirely by precipitation, that is, that the plants growing at the surface are supplied with nutrient elements exclusively by atmospheric sources such as dust, rain, and snow, rather than by groundwater. It is therefore excluded from all non - atmospheric inputs of particulate matter. Moreover, since water movement at or near the bog surface is slow and limited, any deposited matter remains largely. A history of particulate atmospheric pollution is therefore preserved as the peat accumulates. Ombrotrophic peat bogs are very suitable environmental archives because all the nutrient and pollutant entries stem from dry and wet deposition from the atmosphere only. Peat bogs provide widespread terrestrial archives of Holocene environmental change and atmospheric metal deposition. During the last 20 years, peat cores from ombrotrophic peat bogs have proved to be meaningful archives of atmospheric deposition of trace elements. Lead especially has been extensively studied and its immobility in the peat column is well demonstrated. Other elements have also been preserved in the peat column. It is concluded that particular strengths of the archive are the current diversity of peat - based palaeo - environmental research and the potential for multiproxy analyses to be applied to a range of research issues. Dating recent peat deposits has emerged as an important task for estimating rates of organic matter accumulation and atmospheric pollutant deposition in peat bogs. The dating approaches include both continuous dming methods and chrono- stratigraphic markers that can be measured in peat and correlated temporally with known historical events. And multiple dating techniques were recommended to employ.The slightly insufficient parts of the overseas research on peat bogs archives are more focused on ＂records＂, but paid less attention on ＂mechanism＂ research. Recently, scientists from many disciplines have to the global environment. gradually recognized the importance of peat bogs to the global environment.
出处
《湿地科学》
CSCD
2006年第1期69-74,共6页
Wetland Science
基金
国家自然科学基金项目(40471136)
吉林省生态恢复重点实验室开放基金(DS2004-01)资助。
关键词
泥炭沼泽
大气沉降档案
进展
peat bog
achieves of atmospheric deposition
advance the importance of peat bogs
