Response of chronology of Pinus armandi to ecoclimate indicator in Liupan Mountain, Ningxia Province
XU Kang, WANG Xiao-Hui, XU Meng-Chao, WANG Bang, GUAN Wen-Ban
1.Nature Reserve College of Beijing Forestry University; 2.Key Lab. of Soil & Water Conservation and Desertification Combating, Ministry of Education, Beijing Forestry University: 100083, Beijing,China
Abstract:The correlation analysis between chronology of Pinus armandii in Liupan Mountain and ecoclimate indicators was established to reconstruct the substitution data for surface moisture status from 1953 to 2003. The correlation analysis between chronology and single climatic factors (mean temperature and precipitation) showed that the radial growth was more sensitive to the temperature from May to July and the precipitation of March and May. Compared with the single climatic factors, the aridity index was a better ecoclimate indicator that could indicate the local complex surface conditions. Using regression equation between standard treering chronology and aridity index, surface conditions from 1953 to 2003 were reconstructed. The results showed that there were two relatively drought periods: 19531963 and 19932003, and the reconstructed series displayed significant cycles of 4-7 years. The aridity index increased gradually since 1980s, and the annual precipitation would be at lower level in a few years. The aridity index would be 23.5 in 2011, being still in the drought period.