RESUMO
Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10-12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.
Assuntos
Biodiversidade , Florestas , Mapeamento Geográfico , Árvores , Modelos Biológicos , Especificidade da Espécie , Árvores/classificação , Árvores/fisiologia , Clima TropicalRESUMO
INTRODUCTION: Since 2020, it has been possible in Germany to complete a primary qualifying degree in nursing in addition to vocational training in nursing. The study presented here investigates the extent to which the intended competence goals prepare students for the future fields of activity of university-qualified nurses. METHODS: The research question was answered (1) by means of a content analysis of module manuals for primary qualifying courses, specifically the information on the intended learning outcomes in the university part of the course, and (2) by evaluating the results of the analysis in focus groups with those responsible for the course. The areas of competence were used as evaluation criteria for the analysis of the module manuals. The text elements were coded using the analysis software MAXQDA. In the further course of the analysis, the competence areas were combined into three areas with a view to the task profiles (direct care, indirect care and competence area V/research competence) and the percentage weighting of the competence goals was calculated. Using study results from the project "Investigation of the implementation of the study programs within the framework of university nursing training according to the Nursing Professions Act", the hours spent in these areas and the distribution of presence and self-learning time for direct nursing were determined. The results and the reasons for the curriculum design were then discussed in focus groups with those responsible for the degree program. RESULTS: The module manuals reveal clear differences in formal design. The analysis of the learning outcomes specified in the module manuals according to the competence areas also shows considerable differences in the distribution of the percentages for the individual competence areas. In relation to direct care, the percentages range between 55% and 71%, the hours vary between 2,022 and 3,622 hours. With indirect care, the range is 246 to 520 hours. A comparatively high number of hours is planned for competence area V/research competence (869 to 1,426 hours). Also, the analysis leads to the conclusion that within the degree program with the lowest number of hours of face-to-face teaching only 690 hours of face-to-face teaching are spent on direct care, while the degree program with the highest number of hours provides 1,968 hours for face-to-face teaching. In the focus group discussions, the persons responsible for the degree program took a critical view of the hours spent on developing skills in indirect care in the primary qualifying degree programs. Those responsible for the degree programs also regard the very small number of face-to-face hours at some university locations as insufficient to develop direct care skills. DISCUSSION: The results suggest that the primary qualifying courses in some areas and at some study locations do not adequately prepare for the task profiles intended for HQP.