Holocene atmospheric dust record and its influencing factors from different peatlands in the Altay Mountains of Xinjiang
In this article,we selected Tielishahan peatland and Halasazi peatland in the Altay Mountains,Northwest China as the research objects.We used AMS14C to establish a dating framework and determined trace and macronutrient contents in two peat cores to reconstruct the historical Holocene atmospheric dust de-position process and its influencing factors in high mountainous areas in Northwest China.The results show that atmospheric dust deposition fluxes recorded from Tielishahan and Halasazi peat cores ranged from 22.74 to 76.92 and 18.60 to 198.38 g/(m2·a),respectively.Atmospheric deposition is the main source of mineral ele-ment and water recharge in the Halasazi peatlands,which is more representative of the changes in dust activity in the region.The dust fluxes recorded in the Halasazi peat show higher dust fluxes during the early Holocene and early-middle Holocene periods and lower dust fluxes after the middle Holocene.Compared with other re-gions,the Holocene dust fluxes from the peat record in the Altay region were higher than those from the peat record in the monsoon region.A decreasing trend observed in the Altay region after the middle Holocene,con-trary to the conclusion that the peat records of the monsoon region which showed higher dust fluxes in the late Holocene.The dust sources and the characteristics of the climatic environment were the main reasons for the differences in dust flux variation processes in different regions.Humidity and temperature variations directly affect the vegetation cover status in the dust source area of the northwest arid zone of China,and further affect the variation of atmospheric dust fluxes in the region.However,differences in local environmental and perma-frost variation can also cause significant differences in the atmospheric dust information recorded by different environmental carriers.This study is of great scientific significance for a more comprehensive and accurate un-derstanding of the atmospheric environmental change processes and their main influencing factors in different regions of China.
the Altay Mountains of XinjiangpeatHolocenedust fluxatmospheric deposition
万方数据
维普
