Evaluation and comparison of management approaches (Ecological and Social-Ecological approaches) on soil fertility performance in Sarbisheh city

The purpose of this research was to investigate the interaction between the type of management approach and the type of combating desertification projects on soil fertility function. It is especially important in monitoring and evaluation of these projects. For this purpose, at the first, the range of three types of combating desertification projects including bush planting, constructing a crescent pond and seeding - sowing in two different management approaches, Ecological (Sarbisheh combating desertification project) and socio-ecological approaches ( International carbon sequestration project) in Sarbisheh city of South Khorasan province (which were implemented in 2005) were identified. The reference area was determined in each of them and the profile was dug randomly with five replications. Soil sample was taken from a depth of 0-15 cm. Then, the amount of nitrogen, phosphorus and potassium in soil samples were measured as soil fertility characteristics. The results of analysis of variance showed a non-significant difference between the interaction of management type and desertification index projects on soil potassium content due to the abundance of potassium in the soils of arid regions. However, in relation to nitrogen and phosphorus, a significant difference was observed (P< 0.05). As a result, the highest amount of these elements was observed in socio-ecological management (Respectively 0.19 and 0.005 g/kg) based on bush planting project. Rather, the lowest amount was observed in ecological management based (Respectively 0.14 and 0.002 g/kg) under the same project. The results of this study showed that although bush planting has a greater effect on soil fertility than other projects due to its greater focus on the transfer, planting and irrigation of seedlings and ultimately the increase in vegetation. However, the soil fertility status of this project in the ecological management approach indicates the importance of the type of management, including the implementation, protection and proper operation of projects which will have an important effect on soil fertility performance. The socio-ecological management has thus been able to achieve more success in this field due to the active participation of the local community in all stages of planning, implementation, monitoring and operation, and better protection of the revived areas. Therefore, it can be concluded that although the restoration of the structure and function of the ecosystem is the main aim of all restoration activities, its sustainability process is largely related to the motivation of stakeholders and the effectiveness of economic, social and political mechanisms.