Year: 2021
Type: article
Abstract: Vegetation changes play an important roles in climate change. Information from patterns and trends of these factor reveals the state of the climate in a particular area and can be used to set up a proper monitoring program. This study aimed to investigate the annual seasonal patterns and trends of Normalized Difference Vegetation Index (NDVI) by sub-region and by region and to estimate NDVI increase per decade by region in Taiwan. NDVI time series data from 2000 to 2020 were downloaded from the MODIS website. The natural cubic spline method was used to model NDVI annual seasonal patterns and linear regression was used to investigate the trends. Furthermore, multivariate regression was applied to adjust spatial correlation and to estimate NDVI increases in each sub-region and region. The results show the NDVI increase in March of sub-region 1, 2, 3, 4, and 7 and sub-region 3 and 6 show two peaks in each year. The trends show sub-region 8 in region 1 had the highest mean NDVI which was above 0.8, while sub-region 2 had the lowest mean NDVI which was below 0.4. However, NDVI shows increasing trend in almost sub-region except sub-region 15, 22, 23, 27 and 36. In addition, the NDVI in all regions had increasing trends, except in the eastern Taiwan with stable trend. The average increased of NDVI was 0.01 per decade. In conclusion, vegetation index in Taiwan is considerably increasing while the causes of the increasing trends need to be examined in further studies.
Institutions: Prince of Songkla University, Fatoni University
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDGs: Climate action, Life on land
Open Access status: hybrid
Awards: G5342761335, G7856679626
OpenAlex ID: W7220369643