Identifying the spatio-temporal variations of Ulva prolifera disasters in all life cycle. Issue 2 (16th November 2021)

• Record Type: Journal Article
• Authors: Zhang, Baowei; Guo, Jianzhong; Li, Ziwei; Cheng, Yi; Zhao, Yao; Boota, Muhammad Waseem; Zhang, Yaonan; Feng, Liqiang
• Is Part Of: Journal of water and climate change. Volume 13:Issue 2(2022)
• Page Start: 629
• Page End: 644
• Publication Date: 2021-11-16
• Subjects: life cycle -- NDVI -- spatio-temporal variations -- Ulva prolifera; Water -- Periodicals; Hydrology -- Periodicals; Climatic changes -- Periodicals; Climatic changes; Hydrology; Water; Electronic journals; Periodicals; 333.9116
• DOI: 10.2166/wcc.2021.424
• Languages: English
• ISSNs: 2040-2244

Abstract

Abstract: Since 2007, Ulva prolifera disasters have occurred every year in the South Yellow Sea of China, the largest green tide disaster in the world. The inter-annual differences make monitoring and early warning for such disasters difficult. This study used remote sensing data (2015–2019) to determine its spatio-temporal variations in all life cycles. The results showed a lay effect between the NDVI-mean and the coverage area of U. prolifera . The spatio-temporal distribution of U. prolifera showed stages and regional differences. From late April to early May, U. prolifera first emerged near the Subei Shoal. After development in the middle of the Yellow Sea, U. prolifera broke out in the eastern sea area of Shandong and Jiangsu, declined in the Shandong sea area, and disappeared near Qingdao. The cycle lasted for approximately 90 days. The sea surface temperature was the necessary condition for the disaster, and the sea wind field was the main driving force for its horizontal drift. This study overcomes the poor timing and continuity of remote sensing data in the monitoring of U. prolifera . It provides a theoretical reference for forecasting the outbreak period of U. prolifera and can aid policy-makers to avert such disasters in advance. HIGHLIGHTS: There is a significant hysteresis effect between NDVIM and the U. prolifera coverage area. U. prolifera disasters at different growth stages are geographically regional. Sea surface temperature and sea wind field are the main influencing factors of U. prolifera disaster. NDVIM can provide a scientific theoretical reference for predicting the future outbreak period of U. prolifera . Graphical Abstract