In this study. the trends of changes of the standardized precipitation index in a 12-month timescale (SPI-12) and seasonal and annual precipitation were investigated in 21 humid and semi-arid stations of Iran during the 1976-2014 time period. After removing the serial correlation of some series. the trend of precipitation and SPI-12 was detected using the Mann-Kendall nonparametric tr... https://mabelandfoxs.shop/product-category/high-chair/