PROGRESS IN GEOGRAPHY ›› 2015, Vol. 34 ›› Issue (10): 1297-1305.doi: 10.18306/dlkxjz.2015.10.010

• Model and Remote Sensing Application • Previous Articles     Next Articles

Spatiotemporal variations of forest phenology in the Qinling zone based on remote sensing monitoring, 2001-2010

Haoming XIA1,2, Ainong LI1,*(), Wei ZHAO1, Jinhu BIAN1,2, Guangbin LEI1,2   

  1. 1. Institute of Mountain Hazards and Environment, CAS, Chengdu 610041, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2014-12-01 Accepted:2015-05-01 Online:2015-10-20 Published:2015-10-20
  • Contact: Ainong LI


Plant phenology is one of the most salient and sensitive indicators of terrestrial ecosystem's response to climate change. Understanding its spatiotemporal change is significantly important for understanding both land surface processes and carbon cycle and predicting changes in the terrestrial ecosystem. MODIS MOD09A1, with the spatial resolution of 500 m × 500 m and at an 8-day temporal interval, was used in this study to investigate the change in forest phenology in the Qinling zone of central China in 2001?2010. First, we used the day of year (DOY) of MOD09A1 to improve the temporal precision of EVI; we then combined the maximum ratio and the threshold method for phenology data extraction [start of growth season (SOG), end of growth season (EOG), and length of growth season (LOG)] in the Qinling zone. Results of this study show that: Accompanying the deterioration in heat and water conditions from low altitude to high altitude and southeast to northwest, SOG delayed, EOG advanced, and LOG shortened gradually. SOG and EOG mainly occurred on the 81th?120th and 270th?311th days respectively. LOG was mainly between 150 and 230 days. The phenology of forest in Qinling zone is closely related to altitude, with every 100 m rising in altitude, SOG, EOG, and LOG gradualy delayed 2 days, advanced 1.9 days, and shortened 3.9 days, respectively. From 2001 to 2010, early SOG, late EOG, and extended LOG mainly occurred in medium altitude. SOG, EOG, and LOG gradually delayed, advanced, and shortened respectively in some areas that are lowered than 1,000 m above sea level. Interannual changes at high altitude were more complicated than that at low altitude, and SOG advanced, EOG advanced, and LOG shortened above 2000 m. The reasons for these changes remain unclear. The findings quantified the differences of forest phenology with the change in elevation and revealed the spatiotemporal variations in forest phenology from 2001 to 2010. This article provides a reference for the evaluation and protection of ecological environment in the Qinling zone. In future study, reasons for the above mentioned differences in forest phenology need to be explored.

Key words: EVI, HANTS, phenology, spatiotemporal variation, Qinling zone