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In this paper we analyse and compare the efficiency of electrical resistivity imaging (ERI) and ground-penetrating radar (GPR) as tools for stratigraphic and sedimentological studies. To this end, we carried out borehole drilling and geophysical survey campaigns in two locations in Las Tablas de Daimiel area (Ciudad Real, Spain). In this region, the Quaternary record is build up by siliciclastic deposits (gravel, sand and silt) of fluvial origin and organic matter-rich sediments (peat, clay and silty clay rich in organic matter) and carbonates (biogenic deposits mainly made up of Characeae) deposited in fluvial wetland environments that rest on Ordovician quartzites and Pliocene karstified carbonates. Electrical resistivity imaging (ERI) supported by surface and subsurface (boreholes) lithological information allow to identify the geometry of the basement-Quaternary boundary in two areas. The morphology of this boundary is controlled by fractures and the karstification of the top of the Pliocene limestones. Thirteen GPR profiles (100 and 250 MHz antenna) provide information about the morphology and internal structure of the sedimentary units, down to 4 m below the surface. The observed features include: onlap of the sediments on the edge of the basin, fossilization of small paleo-reliefs by lacustrine deposits and channel fills in the Holocene deposits, and the sinking-collapse structures in the Neogene substratum. [ABSTRACT FROM AUTHOR]

Las Tablas de Daimiel National Park (TDNP), recognized as both Biosphere reserve by UNESCO and Ramsar site, is one of the last representatives in the Iberian Peninsula of Mediterranean wetlands linked to groundwater dynamics. It constitutes an outstanding flora and fauna reserve. The inappropriate agricultural management of the groundwater resources that support the system has caused the drying up of the wetland from 2004 to 2009. As a consequence, a smouldering peat fire started inside the TDNP in August 2009. This fire poses an enormous risk for both the physical structure supporting the ecosystem and the quality of groundwater beneath it. The situation got worse in September when a surface fire in the eastern limit of the Park, 3.5 km away from the first underground seat, transmitted to the subsoil giving rise to a second smouldering peat fire outside the Park. The analysis of key parameters monitored in several locations of the TDNP at different depths, such as soil moisture, temperature and organic matter content, shows there was enough previous evidence to foresee the peat self-combustion and the risk that any surface fire could be transmitted to the subsoil. The relatively small size of the Park, the knowledge of the spatial distribution of peat masses, together with the detailed knowledge about soil and vadose zone structure, have allowed to design and execute an emergency plan to hold the fire back. The experience has allowed to check for strong and weak points in the vigilance and alert system implemented, to confirm the effectiveness of the measures applied for the fire control and to propose short and long term actions for preventing fires from starting in the future. [ABSTRACT FROM AUTHOR]

The article presents a study on the estimated average infiltration losses at Las Tablas de Daimiel National Park, a series of wetlands in Spain. It presents a background of Las Tablas de Daimiel along with factors that causes degradation of 50% of the wetlands in the world. It discusses the methods used in the study such as a computer program that calculates infiltration. Details on the estimating infiltration from field data based a field campaign and calculation of daily water balances are offered. Moreover, it cites a validation mechanism that allows verification of the potential utility of the wetland management practices' calculated infiltration.