Evaluation of soil and water conservation projects through estimation of erosion intensity by geomorphological modelling (case study of Safaroud watershed, Mazandaran Province, Iran)

Abstract

Abstract. Various projects have been implemented to control erosion and conserve soil/water resources. One method used to evaluate soil and water conservation projects involves mapping of erosion across a region. This study employed geomorphological methods and the so-called Analytic Hierarchy Process (AHP) technique to prepare an erosion map of Safaroud watershed in Mazandaran Province, Iran, with the aim of evaluating soil and water conservation projects. The erosion map of the region under study was compiled at two reference points in time: prior to project implementation (1994) and after projection completion (2014). The map for the erosion trend of each working unit was prepared either as positive or negative, based on a comparative examination of the erosion map for each working unit against another working unit at the two reference points in time. The effectiveness of projects in each working unit was evaluated by matching the erosion map compiled through maps of soil and water conservation projects implemented across the region. After the statistical analysis of erosion intensities before and after project implementation, the results indicated no significant relationship between the erosion intensities before and after project implementation, at an error level of 0.05. However, most of the units where the erosion trends turned upwards were located along the margins of villages, mainly due to unsystematic development of the rural areas. Erosion intensities were reduced in most of the forested areas, indicating effectiveness of project implementation in those areas.