Assessing the effectiveness of conservation practices under changed climatic conditions has proven to be invaluable in selecting the adaptation practices. Conservationists are concerned that past effective practices may no longer be effective in the future climate change. This research is aimed at assessing the effectiveness of soil and water conservation practices under future climate change, with respect to sediment yield leaving a watershed. For this purpose, the Soil and Water Assessment Tool, SWAT, was applied to simulate various climate change scenarios with three soil and water conservation practices to assess possible changes in stream flow, and sediment yield of the Gorganroud watershed in the northern part of Iran. Study results demonstrated that the impact of climate change in the increase of watershed sediment yield is more than the stream flow and varies from 35.9 to 47.7% for the period 2040–2069. Implementing conservation practices under climate change can reduce the sediment yield of watershed up to 7.2% and for the sub-basin scale up to 46.4%. Range management practices were found to be the most effective practice in the decrease of sediment at the sub-basin scale and porous gully plugs and terrace construction, the most effective at the watershed scale. The results indicate that soil and water conservation practices will be more effective at reducing sediment yields under anticipated future climates. Though, implementation of each conservation practice solely was not sufficient to compensate for climate change-driven increases in sediment yield. This study provides valuable information for watershed managers and decision makers regarding selection of soil and water conservation practices for adaptation to climate change.

Keywords