Acta Geographica Sinica ›› 2010, Vol. 65 ›› Issue (11): 1345-1354.

### Pollen Assemblage of Farmlands in Central and Southern Hebei Province

PANG Ruiming1,2, XU Qinghai1,2,3, DING Wei1,2, ZHANG Shengrui1,2

1. 1. College of Resources and Environment of Hebei Normal University, Shijiazhuang 050016, China;
2. Key Laboratory of Environmental Change and Ecological Development of Hebei Province, Shijiazhuang 050016, China;
3. National Key Laboratory of Western China's Environmental System, Ministry of Education, Lanzhou University, Lanzhou 730000, China
• Received:2010-06-10 Revised:2010-07-24 Online:2010-11-20 Published:2010-11-20
• Supported by:

Key Project of National Natural Science Foundation of China No.40730103; National Science Foundation of China No.40571166; No.40672107; Hebei Natural Science Foundation, No.D2008000186; No.D2009000300

Abstract:

The study on 82 surface soil pollen samples from different types of cultivated vegetations in central and southern parts of Hebei Province indicates that the pollen assemblages from farmlands on the plain have not only their own plant types, but also the pollen components from the nearby mountains. Arboreal pollen percentages and concentrations (dominated by Pinus) of samples from the farmlands in the mountains are higher than those on the plains, and it reduces gradually with the increasing distance away from the mountains. Taking Pinus in Taihang Mountains for example, its content is 20%-30%, 10%-20%, 20%-30% and below 16% respectively for the samples from the area of 0-50, 50-100, 100-150 and more than 150 km away from the east of Taihang mountains. The increase of Pinus proportion in the central plains is probably related to the fohn effect. The spatial variation of AP from mountains to plains in Hebei Province may be similar to the historical change of forests clearance by human activities in early period. Shrubby pollen proportion is small both in mountains and in plains, but their major components are different. Elaeagnaceae, Corylus, Ostryopsis and Oleaceae are common in mountain farmlands, while there are relatively high contents of Rosaceae and Vitaceae in plains, Herb content in plains (about 60%) is 15% higher than that in mountains, among which the Cereals and Cruciferae pollen percentages are 5% and 2% higher respectively. Artemisia pollen percentage on the plains is lower than that in the mountains. Since the human activities are weaker in mountains compared with that on the plains, the general trend is that Chenopodiaceae pollen increases from mountains to plains gradually, reflecting the raising intensity of human activities. The fern spores of Selaginella sinensis in mountains are higher than that on the plains, which is about 7%. The fern spores of Selaginella sinensis are not prone to be spread by wind, indicating that those in the surface soil of the plains may be carried by currents from mountains during the deposition of the plains.