Impact assessment of watershed soil erosion on spatiotemporal distribution of suspended sediment in Jiaojiang Estuary
LU Jianzhong1， ZHANG Chen2， JIN Yan3， LI Jian4， CHEN Xiaoling1
1.State Key Laboratory of Information Engineering in Surveying， Mapping and Remote Sensing， Wuhan University， Wuhan 430079， China；2. Rizhao Land Reserve & Development Group Co. Ltd.， Rizhao， Shandong 276800， China；3. Zhejiang Academy of Surveying and Mapping， Hangzhou 310012， China；4. School of Remote Sensing and Information Engineering， Wuhan University， Wuhan 430079， China
Abstract：The intensity of soil erosion in Jiaojiang Estuary was reached at moderate level at 1995， 2000,2005， 2010 and 2015. From 1995 to 2010， soil erosion tended to deteriorate year by year， but eased from 2010 to 2015. The measured data and model simulation results shows that the suspended sediment concentration in Jiaojiang and Taizhou Bay shows strong spatial distribution and high spatial and temporal dynamics. The suspended sediment concentration in Jiaojiang is significantly higher than that in Taizhou Bay. The average concentration of suspended sediment concentration in the middle reaches of Jiaojiang River is the highest， with the lowest temporal and spatial dynamics， and the maximum turbidity zone of suspended sediment is easy to be formed by land and sea sediment transport. The higher the soil erosion amount is， the higher the sediment concentration is. Rainfall is one of the main driving factors of soil erosion. Rainfall is not only the main driving factor for the production of suspended sediment in the water， but also the main source and recharge of the effective carrier of sediment， as a role of “dilution”. Therefore， rainfall has a double effect on the change of suspended sediment concentration. During the year， the increase of sunshine duration aggravated the loss of water flow and weakened the dilution of water. If the area of building land is used to characterize the intensity of human activities， the correlation between it and annual suspended sediment concentration is weak， while the inter-annual variability of the two species showed a high correlation.
2018, Vol. 52 
