地理と自然災害のジャーナル
オープンアクセス

概要

Correlative and Spectral Analysis of the Rain and the Flows in the Eastern Mitidja Basin (Algeria)

Mébrouk. BENZIADA

The hydrological operation of Baraki, Hammam - Melouane, Keddara II and PontD9 Rouiba systems is treated by correlation and spectral analysis. This descriptive approach is applied to the hydrologic Mediterranean systems and makes it possible to study the behavior of each one of them along several cycles ranging from 1971 to 1985. These analyses show the presence of an "effect memorial or hydraulic reserve" which modulates to a short and a long term the input signal (rain). Choosing the statistical method (correlative and spectral analysis), should lead to better definition of the structure and functioning of groundwater flows. Furthermore, the ANRH hydrometrical stations set up by the main water course of El-Harrach supply with durable average daily outflows, their analysis should result in the definition of the characteristics of superficial flows in order to improve the hydrogeological results and therefore evaluates surface water resources which are most of the time dependent on groundwater.

The correlative and spectral analysis has been used in order to draw up comparisons between the hydrological systems of the studied region, allowing us to determine the connection between their hydrodynamic characteristics. The study of the flow of some water courses crossing the alluvial plain (El-Harrach, Hamiz and Boudouaou) has interlined the fact that the surface hydrological reservoir may be characterized by the capacity of the ground to store reserves. On the applied level, the detailed comparative analysis of the two surface hydrological systems (Baraki and Hammam-Melouane) has brought to light the existence of reserves proportionally more important in the first system than in the second. The results of the two systems show, in an insignificant way, an insufficient groundwater capacity and a high hydraulically transmissivity. Comparatively, and unchaining the 1980-1981 cycle, the hydrological systems of Keddara II and PontD9 Rouiba are little inertial and the water reserves of the Keddara II are more important than those of PontD9 Rouiba.

Applying the correlative and spectral analysis to climatic and hydrologic data may prove to be interesting, it may show whether there is a connection between superficial waters and groundwater whose natural cycles have not, unfortunately, been strictly supervised. Vertical hydraulic connections between groundwater and surface waters however result in repercussions for the latter. A hydrochemical study (chemical tracer) will certainly supply complementary data on the functioning and the structure of deep subterranean flows. The use of mathematical modeling taking into account several physical parameters of the plain will certainly yield interesting results.