Eleven major humidity proxy records and other supplementary evidences including different natural archives such as ice-cores, sedimentary records, river terraces, lake-level fluctuations as well as historical documents are involved to reconstruct the humidity variability in the arid Northwest China during the Little Ice Age (LIA) from 1400 AD to 1920 AD.

In this paper,static research,dynamic research and application research in arid and semi-arid areas in northwest of China are reviewed,and key research fields in the future such as multifunctional wetland lan.