Seeds of Delphinium fissum subsp. sordidum are physiologically dormant at maturity, with underdeveloped embryos; thus they have morphophysiological dormancy (MPD). The aims of this study were to determine the requirements for embryo growth, dormancy break and germination, to characterise the type of seed dormancy and to evaluate the effects of light, seed age, pollination mechanism, and inter-annual and inter-population variability on germinative ability. After 3 months of incubation at 5°C (cold stratification) in darkness conditions, the mean embryo length increased from 5.6 to 2.07 mm, with 76% of seeds germinating. Conversely, embryos of seeds incubated during 3 months at 20/7 or 28/14°C hardly grew and no germination was recorded. Since cold stratification was the only requirement for the loss of MPD, and both dry storage in laboratory conditions and warm stratification prior to cold stratification shortened the cold stratification period required for germination, it could be concluded that D. fissum subsp. sordidum seeds have intermediate complex MPD. Cold stratification and incubation in darkness conditions promoted higher germination percentages than those in light. In addition, germinative ability increased with seed age up to 8 months (reaching 96% at 5°C in darkness), showed a pronounced inter-annual and inter-population variability, as well as a significant decrease in seeds coming from pollination by geitonogamy. High temperatures (25/10 or 28/14°C) induced seeds to secondary dormancy, so seedling emergence in the greenhouse was restricted to February-March. The requirements for dormancy break and germination reflect an adaptation to trigger germination in late winter. This study is the first one to document a gradual increase in germination percentage with seed age for plant species with intermediate complex MPD.

The goal of the study was to investigate the accumulation and spatial patterns of spent lead (Pb) shot pellets and the prevalence of shot ingestion in red-legged partridge in a driven shooting estate. Soil was collected using a regular sampling design perpendicular to three shooting lines. Factors involved in shot spatial distribution were investigated by a causal structural equation model (SEM). Shot ingestion prevalence and liver and bone Pb concentrations were studied in partridges hunted in 2004 and 2006. Shot soil-burden averaged 73,600 units/ha (i.e., 8.1 kg/ha). Shot density was significantly higher in front of than behind shooting lines, with greatest accumulation occurring at between 40-110 m and in certain ecotones (i.e., shrubland-dry cropland). Analyses revealed 7.8% of partridges with evidence of Pb shot ingestion. Particle size in diet, grit-size composition, and shot ingestion prevalence were significantly higher in 2004 than in 2006, indicating that supplying partridges with large seeds (i.e., corn) may increase the risk of Pb shot ingestion. Moving shooting lines into croplands and controlling seed size used for diet supplementation may reduce shot ingestion.

Question: Our knowledge of secondary old-field succession in Mediterranean environments is extremely poor and is non-existent for restrictive soil conditions. How these ecosystems, such as those on semi-arid gypsum outcrops, recover seems a priority for managing change and for ensuring conservation of specialized and endangered biota. We tested whether reinstallation of gypsum vegetation after cropland abandonment requires: (1) soil physical restructuring and (2) chemical readjustment to enable growth and survival of specialized gypsophilous vegetation, and more specifically how time from abandonment drives such environmental change. Location: We sampled a complete set of old fields on gypsum soils (1-60 yr since abandonment) in Villarrubia de Santiago (Toledo, Spain). Methods: Generalized linear models and model comparisons were used to analyse the effect of several environmental parameters on species abundance and richness. Ordination methods (canonical correspondence analyses and partial canonical correspondence analyses) were undertaken to evaluate compositional variation among the sampled fields. Results: Secondary old-field succession on semi-arid Mediterranean gypsum soils was controlled by a complex set of factors acting relatively independently. Surprisingly, time since abandonment explains only a small proportion of compositional variation (3%). Conversely, soil chemical features independently from time since abandonment are important for explaining differences found in oldfield composition.Conclusions: Secondary succession on specialized Mediterranean soils does not follow the widely described ''amelioration'' process in which soil features and composition are closely related over time. Restrictive soil conditions control both structure and functioning of mature communities and also secondary succession.

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