Temporal and Spatial Variations of Vegetation Phenology in the Three Provinces (Regions) of South China from 2001 to 2020

Abstract:

In order to understand the effects of climate change on vegetation phenology in tropical and subtropical monsoon regions of China, vegetation phenology parameters in three provinces (regions) of south China were extracted using Double Logistic method and threshold method based on MODIS EVI time series data from 2001 to 2020, and the spatio-temporal variation characteristics of vegetation phenology were analyzed. The results showed that the start of growing season was mainly concentrated in the 90^th—105^th day, the end of growing season in the 320^th—335^th day, and the length of growing season in the 220^th—235^th day. In the past 20 years, the start of growing season was delayed, the end of growing season was basically unchanged, and the length of growing season was shortened. In terms of spatial distribution, the start of growing season gradually delayed from west to east and from north to south in Guangdong and Guangxi, and gradually delayed from northeast to southwest in Hainan. The distribution of wilting period was late in the center and early in the periphery of Guangdong Province, while it was early in the center but late in the periphery of Hainan Province. The length of growing season gradually shortened from west to east in Guangdong and Guangxi, while it gradually extended from southwest to northeast in Hainan. With the increase of altitude, the start of growing season of different regions and different vegetation varied and fluctuated greatly, while the end of growing season was first delayed and then advanced, and the length of growing season was first extended and then shortened. Therefore, these revealed the change characteristics of vegetation phenology in the three provinces (regions) of south China under the background of climate warming, and had guiding significance for more comprehensive understanding of the response of southern vegetation to climate warming.

Key words:Vegetation phenology;Temporal and spatial variations;MODIS EVI;Tropical and subtropical monsoon zone