Changes in Water Resources Systems:
Methodologies to Maintain Water Security and Ensure Integrated Management
(Proceedings of Symposium HS3006 at IUGG2007, Perugia, July 2007). IAHS Publ. 315, 2007, 9-17
Changes
in water resources availability for crop systems: a case study in the region of
Umbria
FRANCESCA TODISCO, LORENZO VERGNI & ALESSANDRA VINCI
Department of Civil and Environmental
Engineering, University of Perugia, Borgo XX Giugno 74, I-06100 Perugia, Italy
todisco@unipg.it
Abstract
Water resources management must find a solution for competition among
multi-users in agriculture. In particular, water for irrigation purposes, which
has traditionally been the main factor to be satisfied, now competes with other
strategic uses. Added to these socio-political changes are the climatic changes
which influence both the water supply and demand, particularly for agriculture,
which is greatly influenced by meteorological conditions (evapotranspiration,
soil–crop–atmosphere water exchange, crop phenology). The aim of the paper is
to discuss the potential effect of climatic changes on agricultural water
requirements and on agricultural drought risk in the Region of Umbria, Italy.
An analysis aimed at detecting the presence of trends in a set of
meteorological, agrometeorological and drought indices was carried out in five
different areas. Time trends for all variables were analysed using both
parametric and nonparametric approaches. The results show that over the past 54
years the trends are higher in southeastern Umbria. In particular, significant
upward time trends for the thermometric regime and downward trends for the
rainfall regime were found. The irrigation requirements and the drought index show high upward trends at some locations
where expected irrigation demand increments were estimated.
Key
words agricultural
drought index; climate change; crop water requirements