Investigation of Indigenous Knowledge and Techniques of Runoff Harvesting in Arid and Semi Arid Regions of Iran with Emphasize on Economic Benefits

Ali Akbar Nazari Samani

Watershed Management, Faculty of Natural Resources, University of Tehran, Karaj, Iran
e-mail: aknazari@ut.ac.ir

Abstract

Runoff harvesting techniques are often applied to increase the water infiltration and supply as well as productivity in arid regions. Two-thirds of Iran's landmass is considered desert-land devoid of forests and green pastures. Such dire limits in water resources have brought about a general culture of hard work and innovation among nomadic and settled peoples of Iran to innovate and use especial techniques and knowledge for supplying water named indigenous knowledge currently.

Qanat, Khoshab, Bandsar and pastolaism are the most famous of indigenous techniques in water resources management in Iran. In this paper two methods named Bansar and Khoshab will introduce and discuss about their economic benefits.

Bandsar is a kind of structures is prevailing in Khorasan province in east to use runoff in agriculture. It depends on rainfall, land topography and in area of water spreading this site using floods, agriculture has been done. Their area is about .5 to 5 ha in alluvial fans and piedmont plain. Its construction consist of plots, basin and levee along contour line and dry rivers The generated runoff from upland area will be stored in the basin to infiltrate, also proactive trapped sediment in Bandsar will be used as improving and fertile materials for sandy soil. In south east of Iran (Sistan VA Balouchestan province) other traditional method has been used named Khoshab using floods with area about 1-10 ha and cultivation wheat, maize and barely. The best location for Khooshabs is plateaus, flood plains and caused aquifer-feeding. These constructions are built to use the run off generated form Monson rainfall during summer. According to the results the benefit of run off harvesting in traditional techniques depends on natural situation, and generally consist of 150-250US$ per ha. Additionally they acts as an erosion and flood as well as desertification control, preventing immigration of population, increasing productivity and ground water and sustainable development of land. Finally from the results it can be drown that traditional knowledge is closely integrated with economy, environment and society. Based on sustainable cycles its operation leads to the definition of a new technological paradigm.

Keywords: Runoff harvesting, Khoshab, Bansar, Indigenous knowledge, Economic appraisal, Iran