Evaluating temporal sand drift potential trends in the Sistan region, Southeast Iran

Abstract

The Sistan region located in Southeastern Iran is one of the most sensitive areas related to sandstorms and wind erosion in the world. It is well-known that one of the most influential factors in sandstorm interpretation is sand drift potential (SDP), which is directly related to wind speed.However, accurate monitoring of this phenomenon are scarce considering different temporal scales. Therefore, the main aim of this research is to analyze the trend of SDP on monthly and annual scales. Our results showed that monthly variations of SDP obtained the highest and lowest values in July (609 VU) and January (47 VU), respectively. Quicksand moved to the southeast, as well as the directional index fluctuated from 0.88 to 0.94. The annually SDP was equal to 2700 VU, which represents a relatively high value compared to other arid regions of the world. The results of trend analysis applying the Mann-Kendall test showed that there is a positive (1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001) and negative (2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016) trend, but the positive trend is not significant. Furthermore, the results of Sen's slope test demonstrated that the negative trend could be obtained with a higher slope during July, September, and Au-gust; as well a positive trend could be obtained with a higher slope during November, December, and June. We concluded that land managers and stakeholders that are in charge to control quicksand using biological and physical methods should pay attention to these trends in arid environment to apply nature-based solutions or control strategies focusing on these temporal sequences.