T-4464 Buffelgrass (Cenchrus ciliaris L.) is an introduced grass used extensively for restoring forage capacity of denuded shrublands in the arid Chaco region in central western Argentina. Currently, the technique of roller chopping and simultaneous buffelgrass seeding is widespread, but information is lacking about its effects on forage production and other vegetation attributes at the regional scale. The purpose of our study was to compare grass yield; vegetation cover and density; and species richness, diversity, and evenness, between roller chopping and simultaneous buffelgrass seeding with nontreated native degraded shrublands. Eight sites, including matched pairs of treated and nontreated areas, were studied. Grass yield, total perennial grass cover, and total perennial grass density were higher (P , 0.05) on treated areas. Increase in grass yield on treated areas compared with nontreated areas was related to the increase in total perennial grass cover due to added buffelgrass cover (r 2 ¼ 0.79). Shrub cover was lower (P , 0.05) on treated areas, but shrub density was not different between treatments (P . 0.05). Nonsignificant differences (P . 0.05) between treated and nontreated areas were detected in tree cover and density, species number, diversity index, and evenness. The results of this study indicate that, in the short term, roller chopping and simultaneous buffelgrass seeding produces rapid increases in grass cover and grass yield, and a drastic reduction in shrub cover without affecting species diversity on degraded shrublands of the arid Chaco region of Argentina. ResumenEl buffel T-4464 (Cenchrus ciliaris L.) es un pasto introducido, utilizado para restaurar la capacidad forrajera de matorrales degradados en el sector centro-occidental de la regió n del Chaco á rido, Argentina. En la actualidad el rolado y siembra simultá nea de buffelgrass está ampliamente difundido en la regió n. Sin embargo, se carece de informació n a nivel regional, relacionada con los efectos de la aplicació n de esta técnica sobre la producció n de gramíneas y otros atributos de la vegetació n. El objetivo de nuestro estudio fue comparar diferentes atributos de la vegetació n entre á reas roladas y sembradas con pasto buffel y matorrales degradados (testigo). Para ello se seleccionaron ocho á reas roladas y sembradas, y ocho áreas testigo adyacentes. Se evaluó la producció n de gramíneas, la cobertura y densidad de la vegetació n, y el nú mero de especies, diversidad y equitatividad. La producció n de gramíneas, la cobertura de gramíneas perennes totales, y la densidad de gramíneas perennes totales fue mayor (P , 0.05) en las á reas sometidas a rolado y siembra. La mayor producció n de gramíneas en las áreas roladas y sembradas respecto a las testigo, se relacionó positivamente con la cobertura de pasto buffel (r 2 ¼ 0.79). La cobertura de arbustos fue menor (P , 0.05), en á reas roladas y sembradas. Sin embargo, no se detectaron diferencias (P . 0.05) entre áreas en la densidad de arbustos. Tampoco se detectaron d...

In the framework of a PHARE project DBE TECHNOLOGY GmbH carried out a regulatory review of the Preliminary Safety Assessment Report (PSAR) for the near surface LILW repository Baˇit¸a-Bihor, Romania. During the review process several shortcomings of the PSAR from the regulatory point of view were identified. Main findings concerned shortcomings in regard to the operational safety, especially in the field of mining safety. Other points of criticism were connected with the post-closure part of the PSAR. From the regulatory point of view, the long-term calculations appeared to lack a sufficient level of conservatism and the necessary clarity and traceability that would be required to allow a proper evaluation of the concept used for calculating the long-term radionuclide migration and the particular results of the PSAR. Respective recommendations were drafted for the Romanian regulator about the changes that should be implemented in the next version of the Safety Assessment Report. Another focus of this project was an investigation on the potential implementation of the Hydraulic Cage Concept for Baˇit¸a-Bihor. This concept, which originally was developed by DBE TECHNOLOGY GmbH for implementation at the Richard Repository, Czech Republic, helped to decrease the potential future radiological impact for the Richard repository. As the geological situation and the condition of the waste packages are similar for the two repositories, the Hydraulic Cage Concept or some adaptation of it seemed to be an obvious choice to improve the safety of the Baˇit¸a-Bihor repository should that turn out to be necessary. During execution of the review, it became clear that without prejudging the outcome of the next version of the Safety Assessment Report it is likely that some kind of measure will be needed to reduce the potential radiological impact. According to the outcome of the project, an adapted simplified Hydraulic Cage System would be a significant improvement to limit the potential future radiological impact.

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