Wilhelm Barthlott

University of Bonn | Uni Bonn · Nees Institute for Biodiversity of Plants

Wilhelm Barthlott : Publications as PDF available on www.lotus-salvinia.de.: Biodiversity and Bionics We have regularly many requests by students for PDFs of our publications within the research field Biodiversity and Bionics (complete list under www.lotus-salvina.de). We present here a list with links to all abstracts and flyers public available,...

Oil films on water are an increasingly major contamination problem worldwide. In 2020, we published a novel adsorption and transportation technology for oil–water separation based on biological role models like the floating fern Salvinia. This application provides an unexpected ability for the fast and efficient removal of oil films, particularly i...

Certain superhydrophobic plants, such as Salvinia molesta, are able to adsorb oil films from water surfaces and thus separate the oil from the water. There are first attempts to transfer this phenomenon to technical surfaces, but the functional principle and the influence of certain parameters are not yet fully understood. The aim of this work is...

Superhydrophobic surfaces are well known for most different functions in plants, animals, and thus for biomimetic technical applications. Beside the Lotus Effect, one of their features with great technical, economic and ecologic potential is the Salvinia Effect, the capability to keep a stable air layer when submerged under water. Such air layers a...

Plants and other organisms have evolved structures and mechanisms for colonizing land since the Early Ordovician. In this context, their surfaces, the crucial physical interface with the environment, are mainly considered barriers against water loss. It is suggested that extreme water repellency (superhydrophobicity) was an additional key innovatio...

The ability of floating ferns Salvinia to keep a permanent layer of air under water is of great interest, e.g., for drag‐reducing ship coatings. The air‐retaining hairs are superhydrophobic, but have hydrophilic tips at their ends, pinning the air–water interface. Here, experimental and theoretical approaches are used to examine the contribution of...

The interface between leaves and the surrounding environment is formed by the wax-covered plant cuticle, which is hydrophobic and highly impermeable to water and dissolved solutes. The surface itself may become superhydrophobic by complex three-dimensional wax crystals. There is evidence that this system evolved already early with the colonization...

Superhydrophobicity is a physical feature of surfaces occurring in many organisms and has been applied (e.g. lotus effect) in bionic technical applications. Some aquatic species are able to maintain persistent air layers under water ( Salvinia effect) and thus become increasingly interesting for drag reduction and other ‘bioinspired’ applications....

Extreme water repellent ‘superhydrophobic’ surfaces evolved in plants and animals about 450 Ma: a combination of hydrophobic chemistry and hierarchical structuring causes contact angles of greater than 150°. Technical biomimetic applications and technologies for water repellency, self-cleaning (Lotus Effect) and drag reduction (Salvinia Effect) hav...

KOENIGIANA Band 13 (1) 2019 35–42 Bonn, Juni 2019 ISSN 2627-0005 Religionen und Naturschutz Natur und ihr Erhalt spielen in den Schriften und Vorstellungen aller Weltreligionen eine bedeutende Rolle (Übersichten Assisi Declarations 1986, Pye et al. 1997, Micksch et al. 2015, Jenkins et al. 2017). Dies gilt auch für die beiden global dominierenden R...

Plant epicuticular waxes represent the outermost boundary layer of the majority of land plants. Based on their micromorphology and chemical composition they form a multifunctional surface. Their most important functions are the protection against uncontrolled water loss, reflection of solar radiation from UV to visible light, and their crucial infl...

Angiosperms and their pollinators are adapted in a close co-evolution. For both the plants and pollinators, the functioning of the visual signaling system is highly relevant for survival. As the frequency range of visual perception in many insects extends into the ultraviolet (UV) region, UV-patterns of plants play an important role in the flower-p...

Cite this article: Busch J, Barthlott W, Brede M, Terlau W, Mail M. 2019 Bionics and green technology in maritime shipping: an assessment of the effect of Salvinia air-layer hull coatings for drag and fuel reduction. One contribution of 14 to a theme issue 'Bioinspired materials and surfaces for green science and technology'.

In technical systems, static pressure and pressure changes are usually measured with piezoelectric materials or solid membranes. In this paper, we suggest a new biomimetic principle based on thin air layers that can be used to measure underwater pressure changes. Submerged backswimmers (Notonecta sp.) are well known for their ability to retain air...

https://www.klima-warnsignale.uni-hamburg.de/wp-content/uploads/pdf/de/biodiversitaet/warnsignal_klima-die_biodiversitaet-kapitel-1_5.pdf

https://www.bfn.de/fileadmin/BfN/service/Dokumente/skripten/Skript448.pdf

Knowledge of spatial patterns of biological diversity is fundamental for ecological and biogeographical analyses and for priority setting in nature conservation, particularly in West Africa where the existing high biodiversity is increasingly threatened by human activities. The maximum entropy approach was used to model the geographic distribution...

The time dependence of the formation of lotus wax tubules after recrystallization from various chloroform-based solutions on an HOPG surface at room temperature was studied by atomic force microscopy (magnetic AC mode) taking series of consecutive images of the formation process. The growth of the tubules oriented in an upright fashion follows a se...

Video 4. Lotus tubule growth on HOPG from 0.2 mg/mL chloroform wax solution. Only trace images are used for making videos. Size = 3.25 × 3.25 µm, scan rate = 0.519 Hz, 512 lines/image.

Video 6. Lotus tubule growth on HOPG from 0.8 mg/mL (NH4)2SO4 salt saturated chloroform wax solution. Only trace images are used for making videos. Size = 1.2 × 1.2 µm, scan rate = 1.04 Hz, 512 lines/image.

Video 7. Lotus tubule growth on HOPG from 0.8 mg/mL (NH4)2SO4/water saturated chloroform wax solution. Only trace images are used for making videos. Size = 2.05 × 2.05 µm, scan rate = 1.04 Hz, 512 lines/image.

Video 1. Lotus tubule growth on HOPG from 0.8 mg/mL chloroform wax solution. Only (forward) trace images are used for making videos. Size = 1.35 × 1.35 µm, scan rate = 0.796 Hz, 512 lines/image.

Video 2. Lotus tubule growth on HOPG from 1 mg/mL chloroform wax solution. Only trace images are used for making videos. Size = 2.5 × 2.5 µm, scan rate = 0.512 Hz, 512 lines/image.

Video 3. Lotus tubule growth on HOPG from 10 mg/mL chloroform wax solution. Only trace images are used for making videos. Size = 4.9 × 4.9 µm, scan rate = 0.512 Hz, 512 lines/image.

Video 5. Lotus tubule growth on HOPG from 0.8 mg/mL water saturated chloroform wax solution. Only trace images are used for making videos. Size = 3 × 3 µm, scan rate = 1.04 Hz, 512 lines/image.

Underwater air retention of superhydrophobic hierarchically structured surfaces is of increasing interest for technical applications. Persistent air layers (the Salvinia effect) are known from biological species, for example, the floating fern Salvinia or the backswimmer Notonecta. The use of this concept opens up new possibilities for biomimetic t...

Additional AFM images. The supporting information shows AFM images of the air–water interface and the corresponding 3D representations obtained with different set points.

Persistent air layer retention under water (Salvinia effect) is a result of a complex hierarchical structuring of surfaces. Besides providing an impressive silvery appearance it may serve various ecological functions like fluid drag reduction, respiration (plastron effect), sensing and camouflage. In article number 1700273, Jörg J. Schneider, Wilhe...

The Salvinia effect refers to the stable retention of an air layer when submerged in water and is a result of complex hierarchical structuring, ultimate example of which is the surface of the floating fern Salvinia molesta. The air retention capability is technologically interesting as the retained air layer reduces drag force, prevents biofouling,...

An overview of plant surface structures and their evolution is presented. It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications. Within some 3.5 billion years biological species evolved highly complex multifunctional surfaces for interacting with their environments: some 10 million living...

Fog collecting meshes show a great potential to ensure the availability of a supply of sustainable fresh water in certain arid regions. In most cases, the meshes are made of hydrophilic smooth fibers. Based on the study of plant surfaces, we analyzed the fog-collection of different polyethylene terephthalate (PET) fibers with different cross-sectio...

Rethinking the relationship between Homo sapiens and Planet Earth in the Anthropocene is fundamental for a sustainable future for humankind. The complex Earth system and planetary boundaries demand new approaches to addressing our current challenges. Bionics, namely learning from the diversity of life for nature-based technical solutions, is an inc...

The cleanup of accidental oil spills in water is an enormous challenge; conventional oil sorbents absorb large amounts of water in addition to oil and other cleanup methods can cause secondary pollution. In contrast, fresh leaves of the aquatic ferns Salvinia are superhydrophobic and superoleophilic, and can selectively absorb oil while repelling w...

A comprehensive survey of the construction principles and occurrences of superhydrophobic surfaces in plants, animals and other organisms is provided and is based on our own scanning electron microscopic examinations of almost 20 000 different species and the existing literature. Properties such as self-cleaning (lotus effect), fluid drag reduction...

Autogamous species are usually distinguishable from xenogamous relatives by smaller flowers, fewer or even no floral rewards and lower pollen–ovule (P/O) ratios. Many Rhipsalis spp. are small flowered, selfing and include the most widespread species in Cactaceae. However, Rhipsalis also includes a large number of narrowly endemic species and is mos...

Fog collectors can enable us to alleviate the water crisis in certain arid regions of the world. A continuous fog collection cycle consisting of a persistent capture of fog droplets and their fast transport to the target is a prerequisite for developing an efficient fog collector. In regard to this topic, a biological superior design has been found...

Immersed in water superhydrophobic surfaces (e.g., lotus) maintain thin temporary air films. In certain aquatic plants and animals, these films are thicker and more persistent. Floating ferns of the genus Salvinia show elaborated hierarchical superhydrophobic surface structures: a hairy cover of complex trichomes. In the case of S. molesta, they ar...

Wilhelm Barthlott : Publications as PDF available on www.lotus-salvinia.de.: Biodiversity and Bionics We have regularly many requests by students for PDFs of our publications within the research field Biodiversity and Bionics (complete list under www.lotus-salvina.de). We present here a list with links to all abstracts and flyers public available,...

We analyzed the fog collection efficiency of three different sets of samples: replica (with and without microstructures), copper wire (smooth and microgrooved) and polyolefin mesh (hydrophilic, superhydrophilic and hydrophobic). The collection efficiency of the samples was compared in each set separately to investigate the influence of microstructu...

We report a novel, practical technique for the concerted, simultaneous determination of both the adhesion force of a small structure or structural unit (e.g., an individual filament, hair, micromechanical component or microsensor) to a liquid and its elastic properties. The method involves the creation and development of a liquid meniscus upon touc...

The Cactaceae with c. 1,435 species are the most important plant family of the arid regions of the Americas. Recent revisions and molecular studies resulted in an improved knowledge of the phylogeny and taxonomy of this group. Due to their high value as ornamental plants, countless publications with data on ecological preferences and geographic occ...

Abstract: Present world is now facing water shortage for about one billion people. However, fog is an important source of water in certain arid regions, e.g., Namib, Atacama etc. Interestingly, certain plants and animals living in these areas have found distinctive ways to collect fog for their survival. Their surfaces have been being investigated...

Fog is an important source of water in certain arid regions e.g. Namib desert, Atacama desert etc. Efficient and innovative technologies are in need of to exploit the fog to compensate the water crisis in arid regions. The existing technology that has been being used to collect fog for last few decades is a polyolefin mesh but it is not efficient e...

The surfaces of leaves and petals are interfaces of plants to their environment. As plants grow in different conditions and their surfaces have to provide many functionalities, nature developed a great variety of structures and chemistry . These multifunctional plant surfaces serve as models for many technical applications. The self cleaning abilit...

Superhydrophobic, hierarchically structured, technical surfaces (Lotus-effect) are of high scientific and economic interest because of their remarkable properties. Recently, the immense potential of air-retaining superhydrophobic surfaces, for example, for low-friction transport of fluids and drag-reducing coatings of ships has begun to be explored...

Some plants and animals feature superhydrophobic surfaces capable of retaining a layer of air when submerged under water. Long-term air retaining surfaces (Salvinia-effect) are of high interest for biomimetic applications like drag reduction in ship coatings of up to 30%. Here we present a novel method for measuring air volumes and air loss under w...

The Orchidaceae with some 22 000 species is one of the two largest plant families. Despite of the vast literature on orchids, rather little is known about their seeds, which are generally considered as wind dispersed, small and reduced “dust seeds”. Based on some 1400 collections of orchid seeds analysed by SEM and other methods over the last four...

Xylander, Meine sehr verehrten Damen und Herren, vor allem aber: Lieber Ranga Yogeshwar, Im Herbst vergangenen Jahres fragte mich Professor Xylander, ob ich bereit wäre, heute anlässlich der Verleihung des Meridian-Filmpreises an Ranga Yogeshwar die Laudatio zu halten. Meine Freude und Zusage waren ganz spontan und ich bedanke mich für die ehrenvol...

The surface microstructures on ray florets of 62 species were characterized and compared with modern phylogenetic data of species affiliation in Asteraceae to determine sculptural patterns and their occurrence in the tribes of Asteraceae. Their wettability was studied to identify structural-induced droplet adhesion, which can be used for the develo...

Aim Range‐restricted species account for a large proportion of global biodiversity, and many such species are highly threatened by deforestation and intensifying land use in the tropics. The effects of land use on the diversity of range‐restricted species have rarely been studied and remain unknown for vascular epiphytes – diverse and important ele...

We have analysed the global patterns of moss species diversity based on a dataset created from checklists, online databases, and herbarium records. We collected more than 100 000 distribution records for over 400 different geographical units and standardized species taxonomy using the TROPICOS database of the Missouri Botanical Garden. Maps of over...

The limited resources available for the conservation of biodiversity and eco-system services call for prioritisation schemes. For instance, in the process of systematic conservation planning site selection is partly determined by efficiency gains. In this paper we present an alternative method for global spatial priority-setting based on ecological...

Gegenstand mit einer Oberfläche, die — erste Filamente aufweist, die eine Länge von 10 bis 6000 μm und ein Verhältnis von Durchmesser zu Länge zwischen 1:10 und 1:40 haben und mit mindestens einer Stirnseite an die Oberfläche gebunden sind, wobei pro mm2 Oberfläche 1 bis 500 erste Filamente gebunden sind, — zweite Filamente aufweist, die eine Länge...

Tarsal claws, which are common attachment devices in arthropods, interlock with the surface irregularities of the substrata. Most insects have two tarsal claws, but the larvae of some aquatic insects, such as Ephemeroptera and Trichoptera, bear only one claw on their tarsi. The range of surface roughness that is sufficient for the function of the s...

In contrast to advancements in the fabrication of new superhydrophobic materials, the characterization of their water repellency and quality is often coarse and unsatisfactory. In view of the problems and inaccuracies, particularly in the measurement of very high contact angles, we developed alternative methods for the characterization of superhydr...

The basic information necessary for biogeographical analysis is the geographical location appended to the data contained in biological databases. Reliability of analyses thus crucially depends on the quality of the spatial information available. In the present study we build on a database of vascular plants of West Africa (Ivory Coast, Burkina Faso...

Zusammenfassung Mit den superhydrophoben, Luft haltenden Deckflügeln des Rückenschwimmers Notonecta glauca zeigt die Natur, wie die Benetzung einer Oberfläche beim Untertauchen in Wasser erfolgreich verhindert werden kann. Die Auswirkung dieser Eigenschaft auf das strömungsmechanische Verhalten werden mittels μ -Particle-Image-Velocimetry Messtechn...

A typical superhydrophobic (ultrahydrophobic) surface can repel water droplets from wetting itself, and the contact angle of a water droplet resting on a superhydrophobic surface is greater than 150°, which means extremely low wettability is achievable on superhydrophobic surfaces. Many superhydrophobic surfaces (both manmade and natural) normally...

Amborella trichopoda Baill., the most ancestral angiosperm, has been successfully cultivated in the Botanic Gardens of the University of Bonn in Germany (BG Bonn) for more than a decade. The distribution of this plant – limited to the South Pacific island of New Caledonia – and its cultivation has so far only been achieved in a few botanic gardens....

Mimicking nature – from science fiction to engineering reality Humans have always looked to nature’s inventions as a source of inspiration. The observation of flying birds and insects leads to innovations in aeronautics. Collision avoidance sensors mimic the whiskers of rodents. Optimization algorithms are based on survival of the fittest, the see...

• The Cactaceae are a major New World plant family and popular in horticulture. Still, taxonomic units and species limits have been difficult to define, and molecular phylogenetic studies so far have yielded largely unresolved trees, so relationships within Cactaceae remain insufficiently understood. This study focuses on the predominantly epiphyti...

We summarize research on the global centres and gradients of vascular plant diversity. Most centres of plant species richness are located in geodiverse areas of the humid tropics and sub-tropics, especially in forest biomes. When focussing on the rarity of the flora, islands play an outstanding role. Endemism-scaled richness of oceanic island flora...

Es ist also soweit: nach 26 Jahren Tätigkeit als Hochschullehrer in Bonn werde ich pünktlich entpflichtet. Dies ist eine Entscheidung, die über einen längeren Zeitraum heranreifte und in Absprache mit Ihnen, lieber Herr Kanzler Dr. Lutz, getroffen wurde. In den kommenden drei Jahren, in denen ich Mitarbeiter und Räumlichkeiten zur Verfügung habe, k...