Analysis of runoff, sediment dynamics and sediment yield of subcatchments in the highly erodible Isábena catchment, Central Pyrenees
Analysis of runoff, sediment dynamics and sediment yield of subcatchments in the highly erodible Isábena catchment, Central Pyrenees
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比利牛斯山脉中部高度易侵蚀的伊萨贝纳流域的子流域径流、泥沙动力学和产沙量分析
DOI:
10.1007/s11368-014-0990-5
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发表时间:
1920
影响因子:
3.6
通讯作者:
J. A. López-Tarazón
中科院分区:
文献类型:
--
作者:
T. Francke;S. Werb;E. Sommerer;J. A. López-Tarazón
Abstract Purpose: The Isábena catchment (445 km), Spain, features highly diverse spatial heterogeneity in land use, lithology and rainfall. Consequently, the relative contribution in terms of water and sediment yield varies immensely between its subcatchments, and also temporally. This study presents the synthesis of~ 2.5 years of monitoring rainfall, discharge and suspended sediment concentration (SSC) in the five main subcatchments of the Isábena and its outlet. Materials and methods: Continuous discharge at the subcatchment outlets, nine tipping bucket rainfall and automatic SSC samplers (complemented by manual samples), were collected from June 2011 until November 2013. The water stage records were converted to discharge using a rating curve derived with Bayesian regression. For reconstructing sediment yields, the data from the intermittent SSC sampling needed to be interpolated. We employed non-parametric multivariate regression (Quantile Regression Forests, QRF) using the discharge and rainfall data plus different aggregation levels of these as ancillary predictors. The subsequent Monte Carlo simulations allowed the determination of monthly sediment yields and their uncertainty. Results and discussion: The stage-discharge rating curves showed wide credibility intervals for the higher stages, with great uncertainties associated with the discharge rates, especially during floods. The water yield of the subcatchments differed considerably. The entire catchment's output was dominated by the northernmost subcatchment (~ 360 mm year). The smaller, southern subcatchments featured much higher variability and lower runoff rates (55-250 mm year). The SSCs exhibited a wide range and can exceed 100 gl for the central subcatchments, where most of the badlands are located. For the reconstruction of the sedigraphs, the QRF method proved suitable with Nash-Sutcliffe indices of 0.50 to 0.84. The specific sediment yield ranges from relatively low (32 t km year) in the highly vegetated north to high values (3,651 t km year) in areas with many badland formations. Conclusions: The Isábena catchment shows high erosion dynamics with great variability in space and time, with stark contrasts even between adjacent subcatchments. The natural conditions make water and sediment monitoring and instrumentation very challenging; the measurement of discharge is particularly prone to considerable uncertainties. The QRF method employed for reconstructing sedigraphs and monthly yields proved well suited for the task.
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DOI:
--
发表时间:
2004
期刊:
影响因子:
--
作者:
A. Navas;B. Garcés;J. Machı́n
通讯作者:
J. Machı́n
DOI:
--
发表时间:
2000
期刊:
影响因子:
--
作者:
C. A. Salas;M. E. Montero;Rafael Cobo Rayán
通讯作者:
Rafael Cobo Rayán
DOI:
--
发表时间:
2005
期刊:
影响因子:
--
作者:
S. Schnabel;M. Maneta
通讯作者:
M. Maneta
DOI:
--
发表时间:
1999
期刊:
影响因子:
--
作者:
R. Acornley;D. Sear
通讯作者:
D. Sear
DOI:
--
发表时间:
2009
期刊:
影响因子:
--
作者:
J. Thornes;F. López;J. Woodward
通讯作者:
J. Woodward