Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 306703
Title Estimating fluctuation quantities from time series of water-table depths using models with a stochastic component
Author(s) Knotters, M.; Walsum, P.E.V. van
Source Journal of Hydrology 197 (1997)1-4. - ISSN 0022-1694 - p. 25 - 46.
Department(s) Winand Staring Centre for Integrated Land, Soil and Water Research
Publication type Refereed Article in a scientific journal
Publication year 1997
Keyword(s) grondwaterspiegel - modellen - onderzoek - water table - models - research
Categories Soil Physics
Abstract A method is developed to estimate fluctuation quantities of water-table depths independently of the precipitation excess during the monitoring period, whose length is generally limited to 4–10 years. For this purpose, one-dimensional models are calibrated with the precipitation excess as an input variable. These models include the SWATRE soil moisture accounting model, supplemented with a stochastic model for the noise series, and transfer function-noise (TFN) models. The models are used to simulate realizations of time series of water-table depths with lengths of 30 years, from which the mean highest and mean lowest water-tables (MHW and MLW, respectively) are calculated. These estimates can be used in water management for making strategic decisions, because they reflect the conditions of the prevailing climate (i.e. average weather conditions over, say, 30 years) and not just the meteorological conditions during the groundwater monitoring period, which is usually of limited length. The results show that MHWs and MLWs which are estimated from an 8-year series may deviate more than 20 cm from those estimated from 30-year series. The results of the SWATRE models and the TFN models differ only slightly, despite having clearly different theoretical starting-points. The minimum length of series needed for calibration is of practical value; stationary series of 4 years were generally found to be sufficiently long to model the dynamic systems in this study adequately. Both SWATRE models and TFN models could be improved in order to obtain a constant residual variance: in SWATRE models hysteresis of the soil water characteristics could be incorporated, whereas in TFN models a non-constant variance of water-table depths could be taken into account.
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.