Spatio-temporal Characteristics of Integrated Drought in Poyang Lake Basin Based on Multi-source Remote Sensing Data
Drought has serious impacts on agricultural production and ecological environment in China.Study on the causes of drought and drought monitoring technology is crucial for drought warning and mitigation.By considering the atmosphere-vegetation-soil interaction and its mutual feedback mechanism,an attempt to develop anIntegrated Remote Sensing Drought Monitoring Index(IRSDI)was made by a multiple linear regression method based on meteorological stations data and multi-source remote sensing data in Poyang Lake basin from 2000 to 2020.The drought conditions across Poyang Lake basin in both space and time were revealed by SEN trend method and center of gravity migration model.The land use data and nighttime light data were used to construct the human activities pressure index,which was further applied to quantitatively analyze human impacts on the drought pattern in Poyang Lake basin.The results indicated that:(1)The applicability of the IRSDI was well evaluated and validated by using traditional drought index and drought affected area in the statistical yearbook.The proposed IRSDI model was able to accurately and quantitatively monitor the actual drought situation,and to reflect the comprehensive information of both agricultural drought and meteorological droughts.(2)The droughts in Poyang Lake basin was characterized by high drought frequency in the south and low frequency in the north,more severe droughts in the west than in the east,wide spread of droughts,and higher occurring frequency of basin scale droughts.The whole basin showed a wetting trend in summer and autumn,while a drying trend in winter and spring.(3)The impacts of human activities on droughts in Poyang Lake basin showed obvious north-south differentiation characteristics.During the study period,the anthropogenic pressure index increased generally in Poyang Lake basin,and was significantly higher in the north than that in the south.Ecological protection and green development have been implemented in the northern part of Poyang Lake basin,and the anthropogenic pressure inhibited the degree of droughts.Oppositely,extensive socioeconomic development in the south has caused damage to the environment and indirectly aggravated regional droughts.The observed results from this study are of theoretical and practical value for understanding the temporal and spatial variations of droughts in Poyang Lake basin and for enhancing the ability of regional drought prevention and resistance.
NETL
NSTL
万方数据
