A research of aeolian landform in northern China based on remote sensing imagery

Aeolian landform,mainly distributed in northern China,has important impacts on regional ecological security and socioeconomic development.Although great successes were obtained in aeolian landform research in the past decades,timely monitoring of aeolian landform still need improvement because of its inconstant characteristics.In order to investigate recent situation of sandy deserts in China,an aeolian landform dataset was built by extracting landform information from Landsat 7 ETM imageries which were acquired in 2000.In the present study,we focused on aeolian landform in northern China,which is the main aeolian landform region of China,and analyzed characteristics of different sand dune types quantitatively.The results showed that: 1)Aeolian landform is distributed mainly in eight provinces.They are Xinjiang Uygur Autonomous Region,Inner Mongolia Autonomous Region,Qinghai Province,Ningxia Hui Autonomous Region,Gansu Province,Shaanxi Province,Jilin Province and Heilongjiang Province,among them Xinjiang and Inner Mongolia have the largest area and the richest diversity of aeolian landform.2)As for the sand dune morphology diversity,sandy deserts in arid regions are much richer than in sandy lands of semi-arid regions.Among all landform types,some types are generally distributed in all aeolian regions,while some morphologic types are only limited in specific areas,resulting from actions of specific wind velocity,wind direction,vegetation coverage.3)In consideration of dune activity,floating dunes are prevalent in deserts except the Gurbantuggut Desert and the Ulan Buh Desert which are mainly covered by inactive and semi-fixed dunes.In contrast with deserts,sandy lands are dominant by inactive dunes and semi-fixed dunes.This analysis summarized the recent situation of aeolian landform in northern China,and the dataset is important in aeolian landform periodical monitoring and morphologic evolution research.