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Plant regeneration trait syndromes, tradeoffs, and linkages to adult abundance for native and exotic grassland plants
No full textRecruitment is the most sensitive plant life stage to environmental filters. Yet, most research linking functional traits to environmental filters has focused on adult plants with little known about early plant traits, their interactions with environmental filters, or their relation to species abundance. Likewise, how such relationships might vary between native and exotic species or influence plant invasion outcomes is unclear. We quantified regeneration traits for 12 native and 12 exotic (naturalized and invasive) forbs and evaluated trait relationships and their associations with species abundance across an environmental gradient in semi-arid grasslands. Species differentiated along two orthogonal trait axes suggestive of two distinct trait syndromes. The first trait syndrome, likely associated with competitive ability, was correlated with seed mass and growth-related seedling traits. Conversely, the second trait syndrome revealed a tradeoff between traits related to development and growth and traits related to resource management. This syndrome may reflect different approaches for seedling stress tolerance and avoidance. Neither trait syndromes nor mean trait values differed between native and exotic species, whether exotics were invasive or naturalized. Two traits and one trait syndrome were significantly associated with adult species abundance on the landscape. First, species with faster seedling maturation were generally more abundant. Naturalized exotic species with lower specific leaf area were also more abundant, suggesting a possible link between lower specific leaf area and greater drought survival. Abundance of native and invasive exotic species was greater for taxa with faster development and growth and thin, carbon-rich leaves, traits associated with stress avoidance. Importantly, the greater abundance of invasive exotics over other taxa was not accounted for by differences in regeneration traits. Evidence of regeneration trait syndromes and tradeoffs points to important selective forces shaping early plant life-history strategies. Linkages between some of these traits and adult plant abundance also suggest a significant role in recruitment success. Better elucidating these traits and their connections to species abundance—particularly across life stages—can help improve our understanding of plant community assembly
MLUH-E-300_1, Hieraaetus pennatus (Gmelin, JF, 1788), eggshell
No full textInventory No.: MLUH-E-300_1, Object: eggshell, Species: Hieraaetus pennatus (Gmelin, JF, 1788), Preservation: good preservation, Locality_loc.: Dobrudscha, Locality today: Bulgaria/Romania, Country: Bulgaria/RomaniaDate: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 171, Identification by: M. Schönwetter, Aquisition: 1919, Aquired from: R. Tancré, ex Collection: ex. Coll. R. Tancr
MLUH-E-229_1, Geranoaetus albicaudatus hypospodius (Gurney, JH Sr, 1876), eggshell
No full textInventory No.: MLUH-E-229_1, Object: eggshell, Species: Geranoaetus albicaudatus hypospodius (Gurney, JH Sr, 1876), Preservation: heavy damage, Locality_loc.: Colima/Südmexiko, Locality today: Colima, Country: MexicoCollection_coll.: M. Schönwetter, Identification by: M. Schönwetter, Aquisition: 1926, Aquired from: A. Kricheldorff, ex Collection: ex. Coll. A. Kricheldorf
Several candidate size metrics explain vital rates across multiple populations throughout a widespread species' range
No full textIndividual plant size often determines the vital rates of growth, survival and reproduction. However, size can be measured in several ways (e.g. height, biomass, leaf length). There is no consensus on the best size metric for modelling vital rates in plants.
Demographic datasets are expanding in geographic extent, leading to choices about how to represent size for the same species in multiple ecological contexts. If the choice of size variable varies among locations, inter-population comparative demography increases in complexity.
Here, we present a framework to perform size metric selection in large-scale demographic studies. We highlight potential pitfalls and suggest methods applicable to diverse study organisms.
We assessed the performance of five different size metrics for the perennial herb Plantago lanceolata, across 55 populations on three continents within its native and non-native ranges, using the spatially replicated demographic dataset PlantPopNet. We compared the performance of each candidate size metric for four vital rates (growth, survival, flowering probability and reproductive output) using generalized linear mixed models. We ranked the candidate size metrics based on their overall performance (highest generalized R2) and homogeneity of performance across populations (lowest total magnitude of, and variance in, population-level error).
While all size variables performed well for modelling vital rates, the number of leaves (modelled as a discrete variable, without transformation) was selected as the best size metric, followed by leaf length. We show how to interrogate potential trade-offs between overall explanatory power and homogeneity of predictions across populations in any organism.
Synthesis. Size is an important determinant of vital rates. Using a dataset of unprecedented spatial extent, we find (a) consistent size-based models of growth, survival and reproduction across native and non-native populations of this cosmopolitan plant species and (b) that several tested size metrics perform similarly well. This is encouraging for large-scale demographic studies and for comparative projects using different size metrics, as they may be robust to this methodological difference
MLUH-E-92_1, Falco tinnunculus Linnaeus, 1758, eggshell
No full textInventory No.: MLUH-E-92_1, Object: eggshell, Species: Falco tinnunculus Linnaeus, 1758, Preservation: complete preservation, Locality_loc.: Halberstadt, Locality today: Halberstadt, Country: GermanyCollector_leg.: R. Schmidt, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 192, Identification by: M. Schönwetter, Aquisition: 1941, Aquired from: Dr. Henrici, ex Collection: ex. Coll. Dr. Henrici; ex. Coll. R. Schmid
Kompromittierende Faktoren für den mikrochirurgisch anastomosierten Gewebetransfer durch Scapula- und Fibulatransplantate in der rekonstruktiven Mund-, Kiefer- und Gesichtschirurgie
No full textDiese Untersuchung hatte zum Ziel, die Einheilungsquote von Scapula- und Fibulatransplantaten zu analysieren und zu vergleichen. Im Rahmen der vorliegenden Studie wurden in einem Zeitraum von 6 Jahren 64 Scapula- und 30 Fibulatransplantate einbezogen, von welchen 72,3 % erfolgreich einheilten. Kardiovaskuläre Vorerkrankungen zeigten signifikante Zusammenhänge mit einer Anastomoseninsuffizienz und im weiteren Verlauf höheren Verlustraten. Diabetes mellitus korrelierte signifikant häufiger mit Wundheilungsstörungen in der Donorregion. Die Verwendung von großlumigen Anastomosen bestätigte signifikant weniger Minorkomplikationen und es zeigte sich eine Tendenz zur besseren Transplantateinheilung. Darüber hinaus kam es postoperativ bei der Verwendung von großen Hautinseln zu signifikant weniger Komplikationen. Scapulatransplantate erwiesen sich bei kompromittierten Patienten mit Komorbiditäten als vorteilhaft. Essenziell für die erfolgreiche Transplantation ist ein patientenspezifisches Therapiekonzept. Die Evaluierung der biologischen Operabilität konnte anhand eines eigens entwickelten medizinischen Scores quantifizierbar gemacht werden
Stone detection on agricultural land using thermal imagery from unmanned aerial systems
No full textStones in agricultural fields pose a recurring challenge, particularly due to their potential to damage agricultural machinery and disrupt field operations. As modern agriculture moves toward automation and precision farming, efficient stone detection has become a critical concern. This study explores the potential of thermal imaging as a non-invasive method for detecting stones under varying environmental conditions. A series of controlled laboratory experiments and field investigations confirmed the assumption that stones exhibit higher surface temperatures than the surrounding soil, especially when soil moisture is high and air temperatures are cooling rapidly. This temperature difference is attributed to the higher thermal inertia of stones, which allows them to absorb and retain heat longer than soil, as well as to the evaporative cooling from moist soil. These findings demonstrate the viability of thermal cameras as a tool for stone detection in precision farming. Incorporating this technology with GPS mapping enables the generation of accurate location data, facilitating targeted stone removal and reducing equipment damage. This approach aligns with the goals of sustainable agricultural engineering by supporting field automation, minimizing mechanical inefficiencies, and promoting data-driven decisions. Thermal imaging thereby contributes to the evolution of next-generation agricultural systems
MLUH-E-301_1, Hieraaetus pennatus (Gmelin, JF, 1788), eggshell
No full textInventory No.: MLUH-E-301_1, Object: eggshell, Species: Hieraaetus pennatus (Gmelin, JF, 1788), Preservation: slight damage, Locality_loc.: Südfrankreich, Locality today: France, Country: FranceDate: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 171, Identification by: M. Schönwetter, Aquisition: 1919, Aquired from: R. Tancré, ex Collection: ex. Coll. R. Tancr
MLUH-E-376_1, Milvus milvus milvus (Linnaeus, 1758), eggshell
No full textInventory No.: MLUH-E-376_1, Object: eggshell, Species: Milvus milvus milvus (Linnaeus, 1758), Preservation: complete preservation, Locality_loc.: Slavonien, Locality today: Slovenia, Country: SloveniaDate: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 156, Identification by: M. Schönwetter, Aquisition: 1910, Aquired from: Dr. Rey, ex Collection: ex. Coll. Dr Re
Grouping agri-environmental practices in Germany along behavioural drivers for adoption
No full textWidespread adoption of sustainable practices is crucial for a transformation of agriculture towards sustainability. Effective policy interventions to increase their adoption require an understanding of the behavioural drivers of adoption. Based on interviews with twelve experts on German agriculture, this study assesses the importance of a comprehensive set of behavioural factors for the adoption of 18 agri-environmental practices. The rated level of importance of the behavioural factors varies significantly across the practices. While enhancing farmers’ capability in terms of knowledge is confirmed to be a key factor for adoption of most practices, opportunity-related factors such as financial resources, and motivation-related factors such as future-orientation or habits are more specific to certain sub-groups of practices. Cluster analysis reveals three robust groups of practices that share similar behavioural drivers. For instance, a cluster consisting of agroforestry, hedges, and permanent grassland coincided as overall demanding for farmers and difficult to reverse, requiring future-orientation, a favourable legal context without short-term leases, and financial resources. For another cluster – legumes, reduced mowing, reduced tillage, rotational fallow and reduced soil pressure – adoption of the practices may actually save workforce and time for farmers, but - in addition to knowledge needs - depend on proper integration within farmers’ habits and routines. The findings of our study, both at the level of single practices and on cluster-level, can inform the design of targeted policy interventions such as trainings and financial support schemes