Characteristics of ring-width chronologies of Picea crassifolia and their responses to climate at different elevations in the Anyemaqen Mountains Tree-ring-based reconstruction of the temperature variations in February and March since 1890 AD in southern Jiangxi Province, China Reconstruction and analysis of July-September precipitation in Mt.Dagangshan, China Tree Rings of the Jiangya Reservoir and Changes of the Climate during the Recent Hundred Years(1902~1996)in Lou River