بررسی روند تغییر شاخص‌های حدی بارندگی در بروز سیلاب (منطقه مورد مطالعه: جنوب شرقی ایران)

Southeast of Iran and the coast of Makran is the third center of the maximum intensity of heavy rains in Iran, especially in the summer season. Extreme rainfall events play an important role in the occurrence of floods and soil erosion; Therefore, it is necessary to investigate the trend of precipitation limits and their variability in temporal and spatial scales in forecasting and taking action to prevent damages. In this study, out of 3 indicators of daily rainfall intensity (SDII), maximum one-day rainfall (RX1) and days with heavy rainfall (R10) were used to investigate the pattern of extreme rainfall in 19 stations in the southeast region of Iran using the test The nonparametric Mann-Kendall was used over a 21-year period from 2000 to 2020. Also, R software and Rclimdex plugin were used to calculate precipitation limit indices. The research findings showed that during the study period, there is a positive trend for the series of daily rainfall intensity (SDII), maximum one-day rainfall (RX1) and days with heavy rainfall (R10) in most of the study stations. The increasing trend of these indicators is often associated with an increase in the risk of flooding and destruction of soil and vegetation in this part of the country, which involves a lot of costs. Therefore, it is recommended to consider the effects of rainfall limits in order to control and turn the threat of flooding into an opportunity by using soil protection and watershed management methods in the planning and policies