Intermittent, temporary or seasonal rivers or streams cease to flow every year or at least twice every five years.[1] Such rivers drain large arid and semi-arid areas, covering approximately a third of the Earth's surface.[2] The extent of temporary rivers is increasing, as many formerly perennial rivers are becoming temporary because of increasing water demand, particularly for irrigation.[3] Despite inconsistent water flow, intermittent rivers are considered land-forming agents in arid regions, as they are agents of significant deposition and erosion during flood events.[4] The combination of dry crusted soils and the highly erosive energy of the rain cause sediment resuspension and transport to the coastal areas.[5] They are among the aquatic habitats most altered by human activities.[6] During the summer even under no flow conditions the point sources are still active such as the wastewater effluents,[7] resulting in nutrients and organic pollutants accumulating in the sediment. Sediment operates as a pollution inventory and pollutants are moved to the next basin with the first flush.[8] Their vulnerability is intensified by the conflict between water use demand and aquatic ecosystem conservation.[9] Advanced modelling tools have been developed to better describe intermittent flow dynamic changes such as the tempQsim model.[5]
- ^ (Tzoraki et al., 2007)
- ^ (Thornes, 1977)
- ^ (De Girolamo, Calabrese et al. 2012)
- ^ Tooth, Stephen (2000). "Process, form and change in dryland rivers: a review of recent research". Earth-Science Reviews. 51 (1–4): 67–107. Bibcode:2000ESRv...51...67T. doi:10.1016/S0012-8252(00)00014-3.
- ^ a b (Tzoraki et al., 2009)
- ^ (Moyle 2013)
- ^ (Perrin and Tournoud 2009; Chahinian, Bancon-Montigny et al. 2013)
- ^ (Bernal, von Schiller et al. 2013)
- ^ (Webb, Nichols et al. 2012)