HR: 1340h
AN: B33D-1057    [Abstracts]
TI: Eco-hydrological Controls in Mediterranean Agricultural Landscapes
AU: Portoghese, I
EM: ivan.portoghese@ba.irsa.cnr.it
AF: Water Research Institute, Italian National Research Council, via De Blasio, 5, Bari, BA 70123 Italy
AU: Iacobellis, V
B33D-1057 AF: DIAC, Technical University of Bari, via Orabona, 4, Bari, BA 70125 Italy
AU: * Sivapalan, M
B33D-1057 AF: Department of Geography, University of Illinois at Urbana-Champaign, 220 Davenport Hall, MC-150, 607 South Mathews Avenue, Urbana, IL 61801 United States
AB: This work is focused on semi-arid Mediterranean regions as this is the context in which water shortage is endemic and hydrologic prediction becomes crucial as it involves a variety of problems related to water resources management and water balance in general. Moreover water balance prediction has to deal with further complexities coming from the human-induced perturbations interacting with the climate-soil-vegetation dynamics. Vegetation types and agricultural practices play a central role in the control of water balance processes, and the different strategies that they may have developed to succeed in such water-limited environments may be the key for a better understanding and modelling. A bucket approach is employed to model the temporal water balance dynamics, with vegetation water use efficiency being parameterised with the use of empirically obtained crop coefficients. Sensitivity analysis with respect to the root zone depth and soil properties is carried out with the aim of assessing the robustness of model predictions and exploring the possible spatial distribution of these vegetation types within the study region. Based on these sensitivity analyses the degrees of suitability and adaptability of each vegetation type to the study region are discussed. It is argued at this point that eco-hydrological controls such as prolonged periods of soil moisture deficit, and hence of productivity losses, operates as a major mechanism in determining the spatial patters of vegetation by way of the soil water holding capacity which indeed is recognized as a limiting factor for agricultural development. These results represent a robust, though non-conventional, validation of the model-based hypotheses on the spatial patterns of vegetation. In fact, the observation of co-occurrences of soil properties and land-use across a wide region of Southern Italy have shown a tied dependency between these two landscape features which indeed can be useful in modelling water balance even at large scales. Therefore, after a catchment scale validation we argue that eco-hydrological concepts indeed can be exploited as a means to explain water balance variability in agricultural landscapes and to reduce the predictive uncertainty of conceptual models through an alternative and/or complementary approach to traditional field-based knowledge.
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1813 Eco-hydrology
DE: 1874 Ungaged basins
DE: 1876 Water budgets
SC: Biogeosciences [B]
MN: Fall Meeting 2005