Modeling aquifer–river interactions under the influence of groundwater abstraction in the Mancha Oriental System (SE Spain)

Abstract

The results show a high probability of not meeting the groundwater quality standards when 25 deriving a policy from just a deterministic analysis. To increase the reliability several 26 realizations can be optimized at the same time. By using a mixed-integer stochastic 27 formulation, the desired reliability level of the strategy can be fixed in advance. The approach 28 allows deriving the trade-offs between the reliability of meeting the standard and the net 29 benefits from agricultural production. In a risk-averse decision-making, not only the reliability 30 of meeting the standards counts, but also the probability distribution of the maximum pollutant 31 concentrations.A sensitivity analysis was carried out to assess the influence of the variance of 32 the hydraulic conductivity fields on the strategies.The results have shown that larger the 33 variance, greater the range of maximum nitrate concentrations and the worst-case (or maximum 34 value) that could be reached for the same level of reliability. 35

Cambio climático y planificación hidrológica: ¿es adecuado asumir un porcentaje único de reducción de aportaciones para toda la demarcación?

“…En cuanto a la zona de recarga del acuífero de la Mancha Oriental ubicada dentro del Sistema de Explotación (7260 km 2 , se corresponde casi en su totalidad con la subcuenca denominada Molinar), aunque presenta también clima continental, a efectos del presente estudio se ha incluido junto con la subcuenca de Tous (que se extiende desde el embalse de Molinar hasta la presa de Tous) dentro de la zona intermedia. El acuífero de la Mancha Oriental se encuentra hidráulicamente conectado al río Júcar y, debido a la intensa explotación que ha sufrido en las últimas décadas, ha cambiado la relación río-acuífero (Sanz, 2011), pasando de aportar agua al río Júcar (río ganador) a drenarlo (río perdedor), con importantes implicaciones en la gestión del mismo (Apperl et al, 2015). La recarga del acuífero se estima en 169 hm 3 /año, las pérdidas del río en 76.8 hm 3 /año y el recurso renovable en 359.7 hm 3 /año (CHJ, 2014).…”

Stem Biomass Production of Paulownia elongata × P. fortunei under Low Irrigation in a Semi-Arid Environment

“…This is the case of Castilla-La Mancha, a Spanish Mediterranean region in which socio-economic development has been linked to agricultural land use. However, groundwater pumping (406 Mm 3 year −1 , 98% of which are used in irrigated agriculture) has provoked a steady drop in groundwater levels [2]. The volume of water withdrawal is not compatible with the amount of aquifer recharge, estimated at 320 Mm 3 ⋅year −1 by the Hydrologic Plan for the Jucar River Basin [2].…”

“…However, groundwater pumping (406 Mm 3 year −1 , 98% of which are used in irrigated agriculture) has provoked a steady drop in groundwater levels [2]. The volume of water withdrawal is not compatible with the amount of aquifer recharge, estimated at 320 Mm 3 ⋅year −1 by the Hydrologic Plan for the Jucar River Basin [2]. To restore aquifer levels, the Regional Water Authority (Hydrographic Confederation of Júcar River) has set a maximum irrigation volume of 3800 m 3 ha −1 for timber production.…”

Hydro-engineering solution for a sustainable groundwater management at a cross border region: case of Lake Nyasa/Malawi basin, Tanzania

“…A small component of recharge is thought to occur via stream and river bed leakage especially in the lower reaches of the river systems. As there is no long term water level monitoring data recharge has been assumed to be a percentage of the total annual rainfall [39]. Rainfall infiltration rates in the order of 5-20% have been estimated during the model calibration.…”