Turfgrass biomass production and nutrient balance of an urban park irrigated with reclaimed water.

The increasing demand for water resources in arid and semiarid countries has stimulated the use of non-conventional water resources such as reclaimed water. Consequently, turfgrass irrigation with reclaimed water has become a regular practice in these regions. The main goal of this research was to assess the effects of reclaimed water (RW) irrigation in Madrid urban parks by studying changes in grass nutrient balance and its biomass production. Irrigation with reclaimed water led to a grass biomass increase, mainly due to the high proportion of nutrients received through the irrigation water. The main nutrient input in RW irrigation were of Cl, S, K and Na. RW also contributed to a significant increase in nutrient removal by grass. Thus, all this information generated should be taken into account by park managers in order to fulfill the grass aesthetic value and its nutritional requirements in those urban parks irrigated with RW.

Hydrologic modeling in a small mediterranean basin as a tool to assess the feasibility of a limno-reservoir.

The SWAT model was applied to the Ompólveda River Basin (Guadalajara, central Spain) to assess the hydrological feasibility of the Pareja Limno-reservoir. A limno-reservoir is a water management infrastructure designed to counteract some negative impacts caused by large reservoirs under Mediterranean climate. Highly detailed inputs were selected to set up the model. Its performance was evaluated by graphical and statistical techniques and compared with the previous knowledge of the basin. An overall good performance was obtained during the calibration and validation periods (monthly and annual NSE values of 0.67 and 0.60, respectively, for calibration and 0.70 and 0.83, respectively, for validation). Total discharge was well simulated, and flow components prediction was acceptable. However, the model is not accurate at predicting evapotranspiration. Once evaluated, the model was used to simulate the water discharge into the Pareja Limno-reservoir during 2008 and 2009, establishing a water balance and assessing its hydrologic feasibility. The water balance predicted the absence of surplus during summer (2008 and 2009) and autumn (2009), matching up with the decrease of water level and demonstrating the usefulness of SWAT as a tool to evaluate the hydrologic feasibility of the Pareja Limno-reservoir. Very low discharges from the Ompólveda River after a sequence of normal and dry years are the main factors responsible of this phenomenon, whereas the effect of the wastewater flow redirection in the Pareja village is negligible. These results question the usefulness of the Pareja Limno-reservoir during summer, the most favorable season for recreational activities.