Temperature variation along the northern and southern slopes of Mt. Taibai, China

Altitudinal change in temperatures has a major effect on the distribution of plants and vegetation along an elevational gradient in mountainous areas. In order to explore changes in temperatures in Mt. Taibai (3767 in a.s.l.), Qinling Mountains, the highest mountain in eastern mainland China, we used temperature microloggers to measure the temperature throughout a year on the northern and southern slopes. The measurement was conducted at 16 different elevations between 1250 and 3250 m from August 2001 to July 2002. The results showed that with an increase of altitude, the annual mean temperature (AMT) decreased at a lapse rate of 0.34 +/- 0.04 and 0.50 +/- 0.02 degrees C/100 m on the southern and northern slopes, respectively. The lapse rates of monthly mean temperatures (MMT) showed a large seasonal difference, with a higher value in the summer than in the winter, ranging from 0.14 +/- 0.05 to 0.43 +/- 0.05 degrees C/100 m on the southern slope, and from 0.29 +/- 0.03 to 0.63 +/- 0.02 degrees C/100 m on the northern slope. The accumulated temperature above 0 degrees C (ATO) decreased at a lapse rate of 98.6 +/- 13.0 and 142.5 +/- 3.75 degrees C days/100 m along the southern and northern slopes, respectively. The annual mean diurnal range of temperature (ADRT) was higher on the southern slope than on the northern slope, while the annual range of temperature (ART) showed a converse pattern. The ART declined at a lapse rate of 0.24 +/- 0.07 and 0.32 +/- 0.04 degrees C/100 m on the southern and northern slopes. Our results revealed that lapse rates of temperature variables showed large spatial and seasonal changes, and these changes should be taken into account for analysis of vegetation-climate relationships in mountainous areas. (c) 2006 Elsevier B.V. All rights reserved.