Evaluation of the classical statistical, deterministic and geostatistical interpolation methods for estimating the groun
- PDF / 2,717,846 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 31 Downloads / 193 Views
ORIGINAL ARTICLE
Evaluation of the classical statistical, deterministic and geostatistical interpolation methods for estimating the groundwater level S. Shahmohammadi‑Kalalagh1 · F. Taran2 Received: 22 October 2019 / Accepted: 2 October 2020 © Islamic Azad University (IAU) 2020
Abstract Proper management of groundwater resources depends on identifying, modeling and predicting the level of groundwater in the plains for long-term planning and optimal use of the potential of water. To achieve continuous and integrated maps and predict unknown values, interpolation methods can be used. In this research, the classic statistical interpolation methods (including nearest neighbor, natural neighbor, moving average, and triangulation with linear interpolation), deterministic interpolation methods (including inverse distance to a power, radial basis functions and local polynomial) and geostatistical interpolation method (kriging) were used to estimate the groundwater level of Naqadeh plain in the northwest of Iran in the period of 2001–2016. The cross-validation technique was applied to evaluate the accuracy of the various methods, and three indices—the determination coefficient (R2), the root mean squared error and mean absolute error—were used to compare the interpolation methods. The results of geostatistical analysis indicated that the groundwater level is regionalized variable and there is a high spatial structure ratio between groundwater level data. The best-experimented variogram is a Gaussian model with a correlation coefficient of 0.981. According to the results of cross-validation method, the geostatistical interpolation method with the highest accuracy and the minimum error and the classic statistical interpolation methods with the least accuracy and maximum error were introduced as the optimal and inappropriate methods, respectively. Keywords Cross-validation · Kriging · Naqadeh plain · Semi-variogram
Introduction The water-table information in a plain is collected through observation wells in the area and by measuring the water level in the wells relative to ground level. Preparation of water-table contour maps can greatly assist in estimating and predicting aquifer changes. Since the water-table measurement is very difficult and costly, so water-table contour maps are used. Using interpolation methods, continuous and integrated maps are created and unknown values are predicted. Interpolation is one of the most important methods used in zoning studies. The process of estimating values * S. Shahmohammadi‑Kalalagh [email protected] F. Taran [email protected] 1
Department of Water Sciences and Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran
Department of Water Engineering, University of Tabriz, Tabriz, Iran
2
of points lacking data with the help of adjacent and given points is called interpolation. This process is done because of the limitation of point data and the necessity of mapping out the whole of a zone to produce contour maps. Therefore, interpolation is defin
Data Loading...
