Abstract: Seasonal change and spatial distribution pattern of vegetation in the Chongqing region was studied using the distribution index method and the MODISEVI data during 2000-2015. The results showed that:(1) vegetation reduction presented the highest proportion(6.33%) in winter. The reduction was mainly distributed in the valleys, towns and surrounding areas influenced by the reservoir construction and builtup expansion. Stable vegetation presented the highest proportion(88.23%) in autumn. Vegetation increase presented the highest proportion(31.50%) in spring. The increase was mainly distributed in the west hilly region and farming areas in the middle parallelism valley.(2) The areas with dominant vegetation changes are different. Vegetation reduction was mainly distributed in the areas below 400 m elevation and below 6° slope. Vegetation increase was mainly distributed in the areas between 400 and 1 000 m elevation and between 6° and 15° slope. Stable vegetation was mainly distributed in the areas above 1 000 m elevation and above 15° slope.(3) From spring to summer, vegetation reduction moved to lower terrains(< 800 m elevation, < 6° slope), but vegetation increase moved to higher terrains(> 800 m elevation, > 6° slope). From summer to autumn, vegetation reduce moved to higher terrains(> 500 m elevation, > 6° slope), but vegetation increase moved to lower terrains(< 500 m elevation, <6° slope). From autumn to winter, vegetation reduction(> 1 300 m elevation, > 15° slope) was stronger than vegetation increase(> 500 m elevation, > 6° slope) on the high terrains. Vegetation reduction(< 1 300 m, <15°) was weaker than vegetation increase(< 500 m, < 6°) on the low terrains.(4) On the distribution of aspect, vegetation change extent did not present significant seasonal variation across the North, East, South and West directions.
Key words：vegetation coverage; MODISEVI; trend analysis; distribution index; seasonal change