On April 17, The 15th Academic Salon was held by Group of Youth Innovation Promotion Association in the Conference Room on the sixth floor of ISL. Associate Professor Li Xiangzhong, from Institute of Earth Environment, Chinese Academy of Sciences, Hu Guangyin, Associate Professor, from Northwest Institute of Ecological Environment and Resources, Chinese Academy of Sciences, and Professor E Chongyi, from Qinghai Normal University, visited ISL for academic exchanges and gave academic reports. Forum was chaired by Wang Jianping, the director of Key Laboratory of Salt Lake Geology and Environment of Qinghai Province.
On the afternoon of the 17th, Li Xiangzhong first gave an academic report titled "The Stable Isotope Geochemistry and Environmental Significance of the Lakes in the Northeast of the Qinghai-Tibet Plateau". Li Xiangzhong's report focused on the species of lakes and its carbon and oxygen isotope fractionation and its environmental significance. In view of the multi-solutions of the indicative meanings of the carbon and oxygen isotopes in the lake, using the research ideas of “reviewing the past”, the species diversity, isotope fractionation, and isotopic environment of the modern isomorphism of lakes were studied. Applying the knowledge obtained to sedimentary records could provide a reasonable interpretation of the lake's environmental changes. The results of the study showed that there were differences in isomorphic carbon and oxygen isotopes in different lakes. It was pointed out that when isomorphic carbon isotopes were used to reconstruct paleoenvironmental changes, full consideration should be given to the impact of species differences on the reconstruction results. The variation of isosomatic genera and carbon and oxygen isotopes in Qinghai Lake effectively indicated the changes of lake water chemistry conditions and lake primary productivity levels in Qinghai Lake since 32 million years ago.
Afterwards, Hu Guangyin gave an academic report titled "Research on Wind-blown Activities in the Source Region of the Yellow River." Hu first talked about his research team using remote sensing data to find that the increase in desertified land area in the source region of the Yellow River mainly occurred between 1975 and 1990, an increase of 2276 square kilometers. The heavy, medium, and light desertification lands all increased to varying degrees. The increase in moderate desertification lands was the largest, while the increase in heavy desertification lands was least. Later, he said that studies on wind-sanding activities in the source region of the Yellow River during the historical period found that the wind-sand sedimentary ages in the source region of the Yellow River originated from the late Holocene, and the sedimentary ages of the Yellow River source Zoigê basin were distributed in the Early Holocene and Late Holocene, but It mainly focuses on the late Holocene.
In the end, E Chongyi gave an academic report titled "The Study of Chronology of Light-emission Light on Meadow Soil in the Qinghai Lake Basin". E Chongyi described the results of his team's research on the formation age of soils in the Qinghai Lake basin through the light-emission dating method. They found that the montmorillonite loess parent material in the Qinghai Lake basin started to deposit since the last deglacial period (16ka); with humus The bottom boundary of the strata or its junction with the loess parental layer is the time of occurrence of meadow soil formation. It is found that the majority of the existing meadow soil ages are late Holocene since 4 ka.
After the report was completed, the reporters and the teachers and students attending the meeting held heated discussions and exchanges on relevant scientific issues. Some teachers and students from ISL and some teachers and students from the Qinghai Normal University’s College attended the academic salon.
