TITLE:
Comparing and Evaluating Probabilistic and Deterministic Spatial Interpolation Methods for Groundwater Level of Haouz in Morocco
AUTHORS:
Lamiaa Khazaz, Hassane Jarar Oulidi, Saida El Moutaki, Abdessamad Ghafiri
KEYWORDS:
Geostatistics, Kriging, Piezometric Level, Groundwater, Haouz, Morocco
JOURNAL NAME:
Journal of Geographic Information System,
Vol.7 No.6,
December
30,
2015
ABSTRACT: Growing water scarcity is one of the
major challenges of the 21st century, especially in arid and semi-arid climates
such as our study area. The efficient, sustainable and integrated groundwater
management plays a key role for conserving this vital resource. In order to
overcome this issue, the study of aquifer system’s behavior seems necessary.
For this purpose, the areal piezometric level map is an essential tool. As
piezometric level data are spatially limited in sample points, thespatial
interpolation and geostatistics are the best way to produce the needed map.
Several methods exist allowing to approach real values with varying degrees of
accuracy. This work aims to compareand evaluate spatial interpolation
methods for groundwater level of Haouz using a dataset of 39 piezometers. The
deterministic methods used in this study are Inverse Distance Weighted (IDW)
and Radial Basis Functions (RBF) and the probabilistic ones are ordinary
kriging (OK), simple kriging (SK) and universal kriging (UK). This study shows
the difficulty of having a key role to choose the suitable method for given
input dataset. The best model remains the one that, after comparing several
methods, offers the best accuracy, which is assessed using Cross-validation and
statistical indicators. The results reveals that ordinary kriging with trend
removal technique is the optimal method in this case. It indicates the
superiority of this technique with a decrease in Root Mean Square Error (RMSE)
up to 61.67%. It underestimates groundwater level with an average of 2.8%,
which is reliable. The areal piezometric level and associated prediction
standard error maps give additional information and recommendations that
characterize the studied aquifer system and will ultimately improve sustainable
groundwater management.