SOIL WATER SURPLUS, ITS VARIABILITY DURING THE LAST FORTY YEARS IN BUENOS AIRES PROVINCE (ARGENTINA)

O. E. SCARPATI; L. B. SPESCHA, J. A. FORTE LAY AND A. D. CAPRIOLO

Turín, Italia

Congreso; Managing water in a changing world; 2009

Commission for Water Sustainability, International Geographical Union ,International Year of Planet EarthIYPE Groundwater Theme

Soil water surplus and deficit are very common in Buenos Aires province. It belongs to the wide pampean flatlands with an area of 307,571 km2 and it is a large plain with elevations below 300 m. The hills of Tandilia and Ventania, located in the south of the province, reach maximum heights of 520 m and 1,240 m respectively. This paper analyses the soil water surplus from 1968 to 2008 in the 13 sectors of this province according its basins and the National Water Resources. For the statistical study, the series of water surplus data obtained for the period 1968-2008, were adjusted by means of the theoretical Normal Cubic-root probability distribution. An annual threshold value of 300 mm is considered, upper which the damage from flood is the consequence. The data series present values reaching 600 mm in some years. Non statistical significance for annual trend using Mann Kendall test is found but it can be seen temporal variability. Three cycles are visualized through the studied period and, the last one evidences more variability and this result can be connected to Climate Change.