Jucar River Research Articles

Effect of pH, temperature, conductivity and sediment size on thorium and radium activities along Jucar River (Spain)

A study is presented on the distribution of thorium and radium isotopes in sediments, suspended matter and water collected along Jucar river (East of Spain), using low-level α-spectrometry. The first aim of this work is to study the thorium and radium activity in water, sediment and suspended matter and their dependence on pH, temperature, conductivity and sediment sizes along Jucar river. The analysis of activity variation with these parameters will provide information about the dynamics of these radionuclides in rivers. The values obtained for the distribution factors between suspended matter and water (K d ) are also discussed.

The transfer of uranium from sediment to water along Jucar River, Spain

The effect of sediment size, pH, temperature and conductivity on the transfer of uranium from sediment to water has been studied. The uranium concentration and the234U/238U,235U/238U activity ratios were measured in water, sediments and suspended matter sampled from Jucar River, using low level alpha-spectrometry. Distribution factors were obtained from these measurements. A more detailed sampling was done in the neighbourhood of the Cofrentes Nuclear Plant (Valencia, Spain). Total uranium activity,234U/238U activity ratio and distribution factors for234U and238U were found to vary with pH. Leaching and dilution, which depend on pH and salinity, are the probable mechanisms for these changes.

Behavior of uranium along Jucar River (Eastern Spain): Determination of234U/238U and235U/238U ratios

The uranium concentration and the234U/238U,235U/238U activity ratios were studied in water samples from Jucar River, using low-level α-spectrometry. The effects of pH, temperature and salinity were considered and more detailed sampling was done in the neighbourhood of Cofrentes Nuclear Plant (Valencia, Spain). Changes were observed in the uranium concentration with the salinity and the234U/238U activity ratio was found to vary with pH. Leaching and dilution, which depend on pH and salinity, are the probable mechanisms for these changes in the concentration of uranium and the activity ratios.

STUDY ON THE VARIATIONS OF AN EUTROPHIC ECOSYSTEM FROM THE SPANISH MEDITERRANEAN LITTORAL: DATA TO HAVE IN MIN IN THE NUTRIENT DUMPING TO THE SEA

Cullera Bay is a neritic ecosystem placed on the Spanish Mediterranean Littoral largely influenced by the Jucar River, that brings about lower salinities than surrounding waters, and broad variations of its values. An extensive research, with 9 samplings throughout the year, was carried out, measuring both physical and chemical parameters, and the planktonic communities. The trophic status of the ecosystem, the spatial and temporal variations of the nutrients and the planktonic communities were studied, evaluating the influence of the river loads and the littoral dynamics. Some essential basis to allow a suitable emplacement of waste waters disposals along the Valencian littoral are set up in order to minimize the gradual eutrophication of this coast.

Planning And Design Of The New Cullera Harbour

The present Cullera Port, publicly owned, is located on the left bank of the Jucar river, 3 km upstream from the mouth. The port allows both fishing and small craft uses. An agreement between Local and Regional authorities allowed for the relocation of the harbour facilities and new township developments. Consequently technical feasibility studies have been developed since 1993 to accurately define the planning and design of the project. The paper focuses on the studies that were carried out for the relocation of the harbour facilities and new township developments. Results in the following subjects concerning some parts of the planning and design are discussed : coastal impact, statitics and hydraulic analysis of flow regimes and levels, river sedimentation processes for the layout, maritime traffic congestion in the entrance channel, all of this based in different studies, enquiries and questionnaires to users.