INVESTIGATING THE REPRESENTATIVE ELEMENTARY AREA CONCEPT - AN APPROACH BASED ON FIELD DATA

被引：71
作者：
WOODS, R
SIVAPALAN, M
DUNCAN, M
机构：
[1] Centre for Water Research, Department of Environmental Engineering, University of Western Australia, Nedlands, Western Australia
[2] National Institute for Water and Atmospheric Research Ltd, Christchurch
来源：
HYDROLOGICAL PROCESSES | 1995年 / 9卷 / 3-4期
关键词：
SPATIAL VARIABILITY; SCALE; STREAMFLOW; TOPOGRAPHY;
D O I：
10.1002/hyp.3360090306
中图分类号：
TV21 [水资源调查与水利规划];
学科分类号：
081501 ;
摘要：
Changing the scale of observation or averaging has a significant, but poorly understood, impact on the apparent variability of hydrological quantities. The representative elementary area (REA) concept is used as a motivation for measuring inter-storm streamflow and calculating wetness index distributions for the subcatchments of two small study areas in New Zealand. Small subcatchments are combined to provide larger scale samples, and then the variance of specific discharge between similar sized subcatchments is calculated. For small subcatchments (area less than similar to 1 km(2)) this variance is found to decrease with area more quickly than might be expected if the catchments were random samples. Such behaviour is tentatively interpreted as evidence supporting the concept of 'organization'. At larger scales, variance between catchments decreases in a way that is consistent with sampling from a stationary random field. The results from the streamflow data are reinforced by an analysis of topographic data for the two study areas, although some questions remain open. Both the flow and topographic data support the idea that it is possible to find an averaging scale where the variability between catchments is sufficiently small for a 'distribution function' approach to be used in distributed rainfall-runoff modelling. Consistent estimates of the scale at which the study areas become stationary (0.5 km(2) for Little Akaloa, 2 km(2) for Lewis) are obtained using both flow and topographic data. The data support a pragmatic REA concept which allows meaningful averages to be formed: this may be a useful base for further conceptual developments, but it is not appropriate for a classical continuum approach. Further conceptual development combined with field measurement and computer simulation are still required for the REA to have operational impacts. In particular, it is not clear which models are appropriate for use at the REA scale.
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收藏
页码：291 / 312
页数：22
相关论文
共 40 条
  • [1] Anderson M.G., Burt T.P., The role of topography in controlling throughflow generation, Earth Surf. Process. Landforms, 3, pp. 331-344, (1978)
  • [2] Beven K.J., Changing ideas in hydrology–the case of physically based models, J. Hydrol, 105, pp. 157-172, (1989)
  • [3] Beven K.J., Scale considerations, Recent Advances in the Modelling of Hydrologic Systems, pp. 357-371, (1991)
  • [4] Beven K.J., Wood E.F., Sivapalan M., On hydrological heterogeneity–catchment morphology and catchment response, J. Hydrol, 100, pp. 353-375, (1988)
  • [5] Bloschl G., Gutknecht D., Grayson R.B., Sivapalan M., Moore I.D., (1993)
  • [6] Bloschl G., Grayson R.B., Sivapalan M., On the representative elementary area (REA) concept and its utility for distributed rainfall‐runoff modelling, Hydrological Processes, 9, pp. 313-330, (1995)
  • [7] Bowen F.E., (1964)
  • [8] Burt T.P., Arkle B.P., Variable source areas of stream discharge and their relationship to point and non‐point sources of nitrate pollution, pp. 155-164, (1986)
  • [9] Cooper A.B., Nitrate depletion in the riparian zone and stream channel of a small headwater catchment, Hydrobiologia, 202, pp. 13-26, (1990)
  • [10] DeCoursey D.G., Mathematical models: research tools for experimental watersheds, Recent Advances in the Modelling of Hydrologic Systems, pp. 591-612, (1991)
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