为探讨气候变化与人类活动对湖泊环境影响,在云南星云湖水深8.2m处采集1支85cm长的柱状沉积岩心,对沉积岩心中的植硅体分析结果表明,植硅体种类丰富,呈有规律变化,其组合揭示了近160a以来星云湖地区环境演变过程。植物种类之间存在不同的比例关系,而且留下了人为扰动的明显印记。在整个沉积物柱的植硅体组合中,松等大型乔木始终占有很高的比例,而且越到上部比例越大,除了受滇中地区气候地理因素的影响外,可能还有人为的原因。星云湖地区近160a来的气候有明显的波动,由温凉湿润到湿热再到温热的趋势,在20世纪20年代与40年代是高温期,而40年代是最湿热的,这与传统中提到的80年代温室效应说法不相吻合。
The 85 cm core of XY-1 was obtained from the Xingyun Lake,in the central Yunnan Province,southwest China.The objective of the project was to get the geological record of environment change and disclose the relationship between human activities and the natural factors.22 samples were used for phytolith analysis.Many types of phytoliths were found in the samples,showing a good relationship with the environment evolution.Results show that four climatic stages can be recognized according to the records since about 160 a,including the cool period before 1920s,the warm period between 1920s to mid-1950s with the warmest period in 1940s',the cool period between mid-1950s to 1970s and the warm period in 1980s.Vegetation evolution can also be restored according to phytolith records.Human activities were also recorded,such as the denudation and over reclamation during the end of 1950s.The phytolith are sensitive to the environmental changes.However,the increasing human activities may effect the record of the change in the nature.More detailed work should be done for better understanding the relationship between environment evolution and human activities.