Albert - Dieter Stevens

Freie Universität Berlin | FUB · Botanischer Garten und Botanisches Museum

Whereas temporal variability of plant phenology in response to climate change has already been well studied, the spatial variability of phenology is not well understood. Given that phenological shifts may affect biotic interactions, there is a need to investigate how the variability in environmental factors relates to the spatial variability in her...

Whereas temporal variability of plant phenology in response to climate change has already been well studied, the spatial variability of phenology is not well understood. Given that phenological shifts may affect the magnitude of biotic interactions, there is a need to investigate how the variability in environmental factors relates to the spatial v...

Phenology has emerged as key indicator of the biological impacts of climate change, yet the role of functional traits constraining variation in herbaceous species’ phenology has received little attention. Botanical gardens are ideal places in which to investigate large numbers of species growing under common climate conditions. We ask whether inter...

Changes in phenology induced by climate change occur across the globe with important implications for ecosystem functioning and services, species performance and trophic interactions. Much of the work on phenology, especially leaf out and flowering, has been conducted on woody plant species. Less is known about the responses in phenology of herbace...

Plants, fungi and algae are important components of global biodiversity and are fundamental to all ecosystems. They are the basis for human well-being, providing food, materials and medicines. Specimens of all three groups of organisms are accommodated in herbaria, where they are commonly referred to as botanical specimens. The large number of spec...

Transparency as well as complete and traceable documentation of specimens, samples and associated information are prerequisites to comply with laws and regulations in Provider and User Countries to ensure benefits of utilised genetic resources are shared. Besides legal compliance, these measures should also help to build trust among users, supplier...

To realise the goals of Germany's National Biodiversity Strategy, the WIPs-De project aims to contribute to the conservation of 15 endangered plant species for which Germany has a special responsibility (Verantwortungsarten). Six partners, comprising five botanical gardens and one college of education, will participate in the WIPs-De network. Three...

Background and aims: Autumn leaf senescence marks the end of the growing season in temperate ecosystems. Its timing influences a number of ecosystem processes, including carbon, water and nutrient cycling. Climate change is altering leaf senescence phenology and, as those changes continue, it will affect individual woody plants, species and ecosys...

Background/Question/Methods A warming climate is increasing the length of the growing season in many temperature ecosystems, due to both earlier leaf out in the spring and later leaf senescence in the autumn. Spring leaf out is relatively easy to measure, well-studied, and driven largely by temperature. Autumn leaf senescence, on the other hand, i...

Leaf out phenology affects a wide variety of ecosystem processes and ecological interactions and will take on added significance as leaf out times increasingly shift in response to warming temperatures associated with climate change. There is, however, relatively little information available on the factors affecting species differences in leaf out...

Changes of nectar resources offered by hummingbird-visited plants in the eastern Andes of southern Ecuador were studied in an area of 1 hectare over the course of a full year. A total of 3186 flowering plant individuals were visited by hummingbirds, belonging to 67 species, 29 genera and 12 families. The mean nectar volume per flower and day was 38...

Reintroduction of native species has become increasingly important in conservation worldwide for recovery of rare species and restoration purposes. However, few studies have reported the outcome of reintroduction efforts in plant species. Using data from the literature combined with a questionnaire survey, this paper analyses 249 plant species rein...

The diversity of a hummingbird plant community in the eastern Andes of southern Ecuador was studied on the equivalent of a hectare (two 500 ′ 10 m transects) at 1920 - 2100 m a.s.l. over the course of a year. A total of 3186 flowering individuals, representing 12 plant families, 29 genera and 72 species, were found to be visited by hummingbirds. Br...