2 research outputs found
Spatiotemporal changes in Iranian riversâ discharge
Abstract
Trends in river flow at national scale in Iran remain largely unclear, despite good coverage of river flow at multiple monitoring stations. To address this gap, this study explores the changes in Iranian riversâ discharge using regression and analysis of variance methods to historically rich data measured at hydrometric stations. Our assessment is performed for 139 selected hydrometric stations located in Iranian data-rich basins that cover around 97% of the countryâs rivers with more than 30 years of observations. Our findings show that most of the studied Iranâs rivers (>56%) have undergone a downward trend (P value < 0.1) in mean annual flow that is 2.5 times bigger than that obtained for the large worldâs rivers, resulting in a change from permanent to intermittent for around 20% of rivers in Iranâs subbasins. Given no significant change observed in the main natural drivers of Iranian riversâ discharge, these findings reveal the countryâs surface fresh-water shortage was caused dominantly by anthropogenic disturbances rather than variability in climate parameters. It may even indicate the development of new river regimes with deep implications for future surface fresh-water storage in the country. This researchâs findings improve our understanding of changes in Iranian riversâ discharge and provide beneficial insights for sustainable management of water resources in the country
Iranâs agriculture in the anthropocene
Abstract
The anthropogenic impacts of development and frequent droughts have limited Iranâs water availability. This has major implications for Iranâs agricultural sector which is responsible for about 90% of water consumption at the national scale. This study investigates if declining water availability impacted agriculture in Iran. Using the MannâKendall and Senâs slope estimator methods, we explored the changes in Iranâs agricultural production and area during the 1981â2013 period. Despite decreasing water availability during this period, irrigated agricultural production and area continuously increased. This unsustainable agricultural development, which would have been impossible without the overabstraction of surface and ground water resources, has major longâterm water, food, environmental, and human security implications for Iran