Differences and influencing factors between xylem growth phenology and vegetation phenology in Saihanba area
In order to explore the changes and influencing factors of xylem growth phenology and vegetation phenology in Saihanba area,based on xylem growth phenology monitoring da-ta and NDVI data from Saihanba sample point,the optimal threshold value extraction meth-od was used to obtain the optimal threshold value for predicting xylem growth phenology.Based on the threshold,the start and end growth phenology of xylem in Saihanba area from 2010 to 2021 was used to predict.The dynamic threshold method was used to extract vegeta-tion phenology based on remote sensing data,and the difference of xylem growth phenology and vegetation phenology in spatial change and its influencing factors were compared and an-alyzed.The results showed that the beginning of xylem growth was mainly concentrated in the 111-150 days,and the end growth stage of xylem was mainly concentrated in the 235-257 days.The xylem growing season of vegetation was about 96-130 days long.The xylem growth phenology in the Saihanba area was 3-21 days earlier than the vegetation phenology start,which was mainly affected by temperature,precipitation and slope,while the growth end period was delayed by 3-43 days,and the difference was mainly affected by vegetation coverage.The length of the xylem growing season was 9-64 days longer than that of vege-tation phenology,which was mainly affected by precipitation.Since xylem growth was more reflective of the formation period of the tree's carbon sink than vegetation phenology,longer xylem growth phenology indicated more carbon accumulation.
optimal threshold extractionNDVIstart and end growth phenology of xylemvegetation phenology
NETL
NSTL
万方数据
