Analysis of Trends and Abrupt Changes in Streamflow via Innovative Polygon Trend Analysis and BEAST Changepoint Detection

ABSTRACT Streamflow assessment is essential for managing water resources, enhancing agricultural output, and maintaining ecosystem health. This study examined the annual and seasonal variability in streamflow in the Niger River, gauged at Baro Station. The data were obtained from the NRBDA. The coefficient of variation, Mann–Kendall trend test, modified Mann–Kendall test, innovative trend, and innovative polygon trend analysis were used to assess the annual and seasonal variability and trends in streamflow at the Baro gauging station. The results revealed that the annual stream flow is moderately variable, with a CV of 28%. The variations within the seasons ranged from moderate, high to very high. The Mann–Kendall test, modified Mann–Kendall test, and innovative trend analysis (ITA) all revealed significantly increasing trends in annual and seasonal streamflow. The Mann–Kendall test, modified Mann–Kendall test, and ITA all revealed significantly increasing trends in annual and seasonal streamflow. The IPTA revealed significantly increasing trends in the monthly trends of streamflow. The results of increased streamflow at Baro Station may guide water management policies in other locations facing similar challenges by providing insights into how hydrological cycles are evolving and how regions might adapt to these changes. The study concluded that streamflow at the Baro station is experiencing significant increasing trends. As regions around the world are increasingly impacted by unpredictable rainfall and more frequent extreme weather events, this study provides insights into how shifts in streamflow may affect water availability. The study recommended that there is a need for enhanced water management to support agricultural productivity in the region.