Helophyte germination in a Mediterranean salt marsh: gut-passage by ducks changes seed response to salinity

8 pages, 3 figures, 3 tables.Questions: In seeds which are regularly consumed by waterbirds in the field, how does gut–passage modify their response to salinity gradients? Locations: Doñana National Park salt marsh, south-west of Spain. Methods: Seeds of Scirpus litoralis and Scirpus maritimus were collected and force fed to mallards (Anas platyrhynchos). Both the ingested seeds (passage) and non-ingested seeds (controls) were exposed, in germination chambers, to a salinity range similar to that observed in the field (0-32 dS/m). After 30 days, the total percentage germination, the duration of the dormancy period and the germination speed were computed. The response of the different germination parameters to ingestion and salinity was analyzed using generalized lineal models. Recovery tests on seeds that did not germinate in the various treatments and tests of the effect of ingestion on the intrinsic variability in seed response were also performed. Results: An increase in salinity reduced germinability and increased the length of dormancy, while gut passage increased the intrinsic variability of the temporal seed response in both species. In S. litoralis there was a significant interaction between the effects of salinity and passage on germination rate. Passage increased germination rate at low salinities (£2 dS/m) but decreased it at high salinities (≥4 dS/m). Conclusion: Gut-passage by ducks significantly changes seed response to salinity. The outcome of plant-animal interactions can be influenced by environmental gradients. Studies of germination in response to gut passage that do not take such gradients into account may produce misleading results.Financial support from the Spanish Ministry of Environment (MMA, project 05/99) and the Junta de Andalucía (research group #4086) has enabled us to carry out the present work.Peer reviewe

Pre-Roe abortion regulation reform in the U.S. states Diffusion, reinvention and determinism

SIGLEAvailable from British Library Document Supply Centre- DSC:3812.015(97) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Statutory discretion and procedural control of the European Commission's executive functions

By delegating powers and designing administrative procedures, ministers of the Council, the legislators of the European Union, shape the boundaries of the EU administration. This article uses theories of executive politics to test the factors that affect the degree of statutory discretion delegated by the Council to the Commission in secondary legislation. It suggests that discretion increases with 1) the uncertainty facing legislators, 2) the convergence of preferences between the Commission and the pivotal legislator, 3) the use of qualified majority, and 4) policies that require limited involvement of national administrations. It also tests whether discretion is positively correlated with the stringency of procedural control. The article employs regression analysis and co-graduation tests on a sample of legislation and concludes that uncertainty, policy types and informal decision rules are statistically and substantively relevant in explaining discretion. Discretion is also significantly correlated with the stringency of control

Registration Fees for Same-Sex Unions, Local Party Politics and Societal Demand

This article addresses registration fees for same-sex unions and the number of registered gay couples in the German state of Baden-Württemberg. In contrast to the other 15 German states, in Baden-Württemberg each administrative district decides independently about the level of registration fees. Consequently, there is not only considerable variation of the number of registered gay couples across the individual administrative units, but also among the registration fees, which we seek to explain by relying on theories of public administration, policy analysis and political economy. Our findings show that the varying levels of registration fees for same-sex unions are primarily determined by the preferences of parties in the regional legislative committees. In this way, we can demonstrate that the definition of registration fees is politicised, which contradicts the legal principles of equivalency and cost recovery