Pollen And Ecological Significance From Lake Drill In Lakes Of Tongliao, Inner Mongolia Since The Last 40a

On the basis of a 15-centimeter Agula-Lake sediment core and another 33-centimeter Xiaotazi-Reservoir sediment core from Tongliao, the sensitive region to climate changes in eastern Inner Mongolia, quaternary analysis method of pollens was applied to the laboratorial high-resolution research of pollens for vegetation succession in the past 46 years of this region. Comparing with regional meteorological and human beings’historical data, the main results and conclusions are as follows:1. The pollens’record of the past 46 years shows that the two lakes’pollens sediment are mainly composed of herbaceous pollens, which is accounted for more than 75.3%,and average gross of both Chenopodiaceae and Artemisia pollens are more than 76% in herbs.2. Pollens of the 15-centimeter Agula-Lake sediment are separated into four pollen assemblages, revealing the hungriness environment from 1963 to 2005.3. Pollens of the 33-centimeter Xiaotazi-Reservoir sediment are separated into two pollen assemblages. The first assemblage shows Tongliao with grassland from 1970s to the middle 1980s, and the same vegetation has been showed in the second period since late 1980s. At the same time, we can find out how Xiaotazi-Reservoir gradually degrades and becomes dry, basing on the pollen concentration decreasing exaggeratingly in decades.4. Analyzing regional meteorological data, the climate of Tongliao becomes warm and dry gradually in the late 46 years.5. The vegetation of Agula-Lake region adverses to better situation under warmed climate, which is mainly caused by effectual reconstructing measures in this region, such as: protecting grassland, prohibiting over-grazing and reclamation, improving the Keerqin sand-land, etc. But the disappearance of Xiaotazi-Reservoir is one for climatic variation, and another for human beings’over-reclamation, etc.