Effects of watershed management practices on the quadric services of Chehel-Chai Watershed, Golestan Province

Abstract

IntroductionEcological services are the benefits that humans derive from ecosystems and include four categories of provision, regulatory, cultural, and supportive services. Each of these four categories includes a wide range of ecosystem services. In fact, climate control services include hydrological cycles, water supply and biochemicals, land-based processes and various biological processes. In this regard, to reduce the degradation rate and improve the condition of the Chehl-Chai Watershed in the northeast of Iran, several watershed management measures have been implemented.Materials and MethodsThe present study has investigated the extent of changes of supporting service (soil aggregate stability), provisioning (crops and fruits production, timber, and biomass production), regulating (control of soil erosion, runoff control, and carbon sequestration), and cultural (Increase of interaction and sustainability of local communities, increase of landscape aesthetics and tourist attraction and increase of knowledge and educational values) as a result of implementation of restoration measures in Chehl-Chai Watershed of Golestan Province. After quantifying the amount of services, prioritization of measures was done using TOPSIS method to identify and propose the most effective management option to improve services in the study area.Results and DiscussionThe results showed that the effect of watershed management measures on the ecosystem services improvement is not the same for all services, whereas it is highest for the regulating services and decreases towards the provisioning, supporting, and cultural services, respectively. Furthermore, the watershed management measures on improvement of the watershed services of treatment sub-watershed showed a statistically significant difference at the level of 5% (p<0.05). The results of applying TOPSIS method in the treatment sub-watershed showed that walnut orchards have provided the best effectiveness according to the indicators and criteria considered in the study. In other words, watershed management measures, through increasing the vegetation cover have led to more preciptation absorption, reduction of surface runoff and soil erosion in sloping lands and enhancement of landscape aesthetics as well as improvement of stakeholders participation level, social relationships, and income generation through conducting training and extension programs.ConclusionAmong the employed measures, horticultural activities (planting walnut trees) have had the most success and if additional measures are taken and expanded, the success rate can be improved to a more desirable level. The watershed management measures are economically viable and can be implemented by the people. Therefore, in order to optimally manage water and soil resources and make watershed management more effective in improving the services of Chehelchai watershed, horticultural activities intercropped with forage and medicinal plants are recommended. In addition, the criteria, indicators and procedures applied in this study to quantify the effectiveness of watershed measures on ecosystem services can be consulted in developing a methodology or guideline for monitoring and evaluation of watershed management measures.

Keywords

• watershed management measures
• evaluation
• priortitization
• treatment and control sub-watersheds