Constraints on Water Reservoir Lifetimes From Catchment-Wide Be-10 Erosion RatesA Case Study From Western Turkey


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Heineke C., Hetzel R., AKAL C., Christl M.

WATER RESOURCES RESEARCH, cilt.53, sa.11, ss.9206-9224, 2017 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 53 Sayı: 11
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1002/2017wr020594
  • Dergi Adı: WATER RESOURCES RESEARCH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.9206-9224
  • Anahtar Kelimeler: water reservoir, reservoir sedimentation, cosmogenic Be-10, erosion rates, Menderes Massif, Turkey, SEDIMENT TRAP EFFICIENCY, CENTRAL MENDERES MASSIF, PAN-AFRICAN BASEMENT, DENUDATION RATES, COSMOGENIC NUCLIDES, SOIL-EROSION, TERRESTRIAL SEDIMENT, GEDIZ GRABEN, RIVER-BASIN, HALF-LIFE
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

The functionality and retention capacity of water reservoirs is generally impaired by upstream erosion and reservoir sedimentation, making a reliable assessment of erosion indispensable to estimate reservoir lifetimes. Widely used river gauging methods may underestimate sediment yield, because they do not record rare, high-magnitude events and may underestimate bed load transport. Hence, reservoir lifetimes calculated from short-term erosion rates should be regarded as maximum values. We propose that erosion rates from cosmogenic Be-10, which commonly integrate over hundreds to thousands of years, are useful to complement short-term sediment yield estimates and should be employed to estimate minimum reservoir lifetimes. Here we present Be-10 erosion rates for the drainage basins of six water reservoirs in Western Turkey, which are located in a tectonically active region with easily erodible bedrock. Our Be-10 erosion rates for these catchments are high, ranging from approximate to 170 to approximate to 1,040 t/km(2)/yr. When linked to reservoir volumes, they yield minimum reservoir lifetimes between 255 and 1,650360 years until complete filling, with four reservoirs having minimum lifespans of 110 years. In a neighboring region with more resistant bedrock and less tectonic activity, we obtain much lower catchment-wide Be-10 erosion rates of approximate to 33 to approximate to 95 t/km(2)/yr, illustrating that differences in lithology and tectonic boundary conditions can cause substantial variations in erosion even at a spatial scale of only approximate to 50 km. In conclusion, we suggest that both short-term sediment yield estimates and Be-10 erosion rates should be employed to predict the lifetimes of reservoirs.