Effect of river sand and gravel mining on monthly changeability of suspended sediment concentration

Subject Areas : Farm water management with the aim of improving irrigation management indicators

Seyed Hamidreza Sadeghi ¹ , Sudabe Gharemahmudli ² , Abdulvahed Khaledi Darvishan ³ , Hossein Kheirfam ⁴ , Mahboobeh Kiani Harchegani ⁵ , Pari Saeidi ⁶

1 - Professor, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
2 - M.Sc. Student, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
3 - Assistant Professor, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
4 - PhD Students, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
5 - PhD Students, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran
6 - PhD Students, Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor 46417-76489, Mazandaran, Iran

Received: 2013-10-30 Accepted : 2014-06-20 Published : 2014-06-21

Keywords: Mining, sediment behavior, suspended load,

Abstract :

Data acquisition on effects of type, amount and transportation processes of sediment load at different temporal and spatial scales due to sand mining activities is essential for proper and better management of sand harvesting. Nevertheless, different aspects of effects of sand mining activities on sediment load changeability at different temporal and spatial scales have been less considered. The present research has been therefore formulated to investigate the effect of sand and gravel mining activities of three mines located on Mazandaran Province viz. Vaz-e-Oulia mine with light and traditional harvesting, Vaz-e-Sofla mine with semi-heavy harvesting and Alesh-Roud mine with intensive harvesting by heavy machinery on suspended sediment concentration load. Toward this attempt, the suspended sediment samples were collected on monthly basis and simultaneously from upstream and downstream of sand and gravel mines from February 2012 to January 2013. The results indicated that the suspended sediment concentration increased at the period of sand and gravel mining activity. It was observed that the suspended sediment concentration in upstream of Vaz-e-Oulia mine increased in June, December, February and March with 40, 5, 23 and 75 percent, respectively. According to the results, the rate of suspended sediment concentration in upstream of Vaz-e-Sofla mine compared to downstream of Vaze-Sofla mine also increased in April, August and February with respective rate of 2, 12 and 36 percent. In addition, the rate of suspended sediment concentration in upstream of Alesh-Roud mine compared to downstream of the study mine increased in May, June and March at tune of 71, 50 and 94 percent. A limited local effect and at a maximum range of a few hundred meters on suspended sediment concentration and in coincidence with harvesting time was also confirmed.