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This paper presents the results of pollen trapping studies designed to quantify the pollen assemblages carried in the winds of the Loess Plateau in Luochuan and Hunyuan. The one-year-collection samples analysis results show that pollen assemblages can be more sensitive to the change of climate than the vegetation composition, because of the change of pollen production. The analysis results of pollen traps in different weather regimes indicate that the pollen influx coming from dust weather contribute more to the total pollen influx than that coming from non-dust weather. The wind speed is the most important influenced factor to pollen assemblages, then the mean temperature and the mean relative humidity, the wind direction also contributes some. Strong wind coming from dust direction can make the percent and influx of Artemisia and Chenopodiaceae increase obviously with averagely higher than over 2.7 times in dust weather than in non-dust samples. The influences of wind speed and wind direction are not serious to some arboreal pollen such as Rosaceae, Quercus , Betula , Pinus and Ostryopsis , which are mainly influenced by temperature or the relative humidity such as Salix , Hippophae , Carpinus , Brassicaceae, Cupressaceae, Fabaceae. [ABSTRACT FROM AUTHOR]

Abstract: Studies of vegetation successions related to climate changes during previous interglacial periods provide important insights into the mechanisms of climate change during the current interglacial and enable predictions of future climate impacts on ecosystems. The Chinese Loess Plateau (CLP), which is particularly sensitive to climate warming, presents an excellent site for such studies. However, few detailed records exist of vegetation and climate variations during interglacial periods on the CLP. This study obtained a series high resolution pollen records from the Luochuan loess-paleosol section on the CLP, and the paper discusses the vegetation and climate histories during three previous interglacial periods (MIS 9, MIS 7 and MIS 5). The Artemisia-Chenopodiaceae steppe vegetation that covered this area between 342 ka and 312 ka changed to Humulus-Chenopodiaceae steppe between 312 ka and 302 ka, and then reverted to Artemisia-Chenopodiaceae steppe after 302 ka. From 250 ka to 237 ka, the vegetation type remained Artemisia-Chenopodiaceae steppe, and then changed to Artemisia-Humulus steppe between 237 ka and 227 ka. Between 227 ka and 195 ka, the vegetation returned to Artemisia-Chenopodiaceae steppe. During MIS 5, vegetation of the study area changed from Pinus-Rosaceae-Chenopodiaceae forest-steppe between 129 ka and 117 ka, to Artemisia-Humulus-Ranunculaceae steppe from 117 ka to 96 ka. After 96 ka, the vegetation types changed to Pinus-Betula-Chenopodiaceae forest-steppe. Comparing these pollen records with other climatic proxies from the CLP and the oxygen isotope records from the Pacific Ocean suggests that vegetation and climate change features around the study site were synchronous with East Asian monsoon variations near 65°N. The regional tectonic uplift probably provided only a subordinate influence on vegetation and climate variation on the CLP during MIS 5. [Copyright &y& Elsevier]