1. One mechanism explaining the success of invasive weeds may be the production and release of al... more 1. One mechanism explaining the success of invasive weeds may be the production and release of allelopathic compounds by the invader that, due to a lack of co-evolutionary history, have harmful effects on plant neighbours in the introduced range. 2. We partially tested this hypothesis by growing seven competing native European plant species either with the introduced Solidago canadensis s.l., one of the most successful invasive plants in Europe or on soil pre-cultivated with S. canadensis. We added activated carbon to the soil to neutralize organic chemical compounds with putative allelopathic effects. Furthermore, we added unsterilized soil inocula from the introduced (Switzerland) or native (USA) range to the soil to test potential confounding effects of soil microbes on invasion success. Untreated sterilized soil served as control. 3. Five out of the seven native species were more competitive against the invasive species in soils with activated carbon than without, supporting the allelopathy hypothesis. However, competitive outcomes were also influenced by the two sources of soil inoculum and by interactive effects of soil inoculum and Solidago origin suggesting that soil microbes alter allelopathic effects. 4. Achillea millefolium , the species least affected by the presence of S. canadensis and with no response to the activated carbon treatment is the only species used in this experiment reported to grow within Solidago stands in Europe, whereas the other European species tested tend to grow at the periphery of invasive Solidago stands. 5. Chemical analysis by LC-MS of Solidago root extracts revealed four main secondary chemical compounds with potential allelopathic effects. Root exudates of Solidago showed a significant inhibitory effect on growth of the model plant species Arabidopsis thaliana. The magnitude of inhibition increased with increasing concentration of the extract. 6. Synthesis. Levels of the four compounds were lower in Solidago populations from the invasive range than in populations of the same ploidy level from the native range. This suggests lower investment of invasive plants into these secondary compounds, possibly because of a higher susceptibility of plant competitors in the invasive range to these substances.
Aims The superior performance of many non-indigenous species in a new range can be attributed to ... more Aims The superior performance of many non-indigenous species in a new range can be attributed to different factors such as pre-adaptation to environmental conditions in new areas or to factors inherent to displacement mechanisms such as loss of co-evolved pathogens and herbivores that increase the speed of evolutionary change towards a shift in allocation from defence to growth and reproduction. To assess the importance of the different mechanisms governing the success of Conyza canadensis, a globally successful invader, we simultaneously tested several recent hypotheses potentially explaining the factors leading to biological invasion. Keywords: allelopathy d biological invasions d Conyza canadensis d EICA hypothesis d generalist/specialist herbivory d latitudinal clines d biogeographic comparison d common garden
Zenodo (CERN European Organization for Nuclear Research), Dec 1, 2020
Abbildung 3: Übersicht der strategischen Handlungsfelder zur Förderung von Biodiversität durch pl... more Abbildung 3: Übersicht der strategischen Handlungsfelder zur Förderung von Biodiversität durch planerische Massnahmen. Illustration: Basil Rüegg Wir haben acht strategische Handlungsfelder identifiziert in Ergänzung zu den konkreten Empfehlungen in den 26 Massnahmenblättern (Anhänge 2 und 3). Die acht Handlungsfelder sind gemäss des Dreisatzes ‚Strategien und Prozesse-Verbindliche & spezifische Vorgaben-Sensibilisierung, Aus-und Weiterbildung & Partizipation, strukturiert. Das dritte Standbein der Sensibilisierung und Bildung erleichtert freiwilliges Engagement und damit die Entwicklung von Leuchtturmprojekten (Abbildung 3): ■ Strategien und Prozesse: Es braucht auf kommunaler, kantonaler und nationaler Ebene eine umfassende strategische Planung zur Erhaltung und Förderung der Biodiversität, der Ökosystemleistungen und der ökologischen Infrastruktur. Dazu sind genügend personelle und finanzielle Mittel erforderlich (Handlungsfeld 1). In einem nächsten Schritt sind fachliche Klärungen zu folgenden Punkten nötig: Integratives Verständnis einer ökologischen und sozialen Landschafts-und Freiraumentwicklung (Handlungsfeld 2), ökologischer Ausgleich als ökologische Aufwertung (Handlungsfeld 3) und die Erweiterung von Zielvorstellungen zur Biodiversität genutzter Landschaften (Handlungsfeld 4).
Anthropogenic changes in climate, land use and disturbance regimes, as well as introductions of n... more Anthropogenic changes in climate, land use and disturbance regimes, as well as introductions of non-native species can lead to the transformation of many ecosystems. The resulting novel ecosystems are usually characterized by species assemblages that have not occurred previously in a given area. Quantifying the ecological novelty of communities (i.e. biotic novelty) would enhance the understanding of environmental change. However, quantification remains challenging since current novelty metrics, such as the number and/or proportion of non-native species in a community, fall
Seed germination and seedling establishment of an invasive tropical tree species under different ... more Seed germination and seedling establishment of an invasive tropical tree species under different climate change scenarios
Böden und die Vielfalt in und auf Böden lebender Organismen sind durch ungezählte Wechselwirkunge... more Böden und die Vielfalt in und auf Böden lebender Organismen sind durch ungezählte Wechselwirkungen verbunden. Akteursgruppen mit unterschiedlichen Interessen nutzen und/oder beeinflussen Böden und Biodiversität auf verschiedene Art und Weise. Sie tun dies-so die These des folgenden Beitrags-überwiegend ohne diesen Wechselwirkungen Rechnung zu tragen und unabhängig voneinander. Damit vergaben sie in der Vergangenheit die Chance, beide Ressourcen wirkungsvoll zu schützen. Welche Ansätze sind potentiell geeignet, den Schutz von Boden und Biodiversität zu verknüpfen? Abstract & Keywords ê p. 239 1) Für die Schweiz siehe [2], für Deutschland siehe [3]. 2) Zu Boden vergleiche [4], Schweizerisches Nationales Forschungsprogramm 22 "Nutzung des Bodens" [5, 6]; zu Biodiversität vergleiche [7-9]. 3) Vergleiche [5] sowie verschiedene Bodenschutzinitiativen von Nichtregierungsorganisationen wie [10] oder die Vorschläge für eine "Bodenkonvention" [6]. 4) Bodenkundliche Gesellschaft Schweiz (BGS). Für die detaillierte Definition siehe Homepage der BGS (www.soil.ch). GAIA 12 (2003) no. 3 Der Baukran rückt näher. Der Boden-und Biodiversitätsschutz ist gefordert, den anhaltend hohen Flächenverbrauch einzudämmen.
Population admixture (hereafter: admixture) is a genetic process of hybridization between previou... more Population admixture (hereafter: admixture) is a genetic process of hybridization between previously isolated populations of one species (Ellstrand & Schierenbeck, 2000). Admixture might, for example, happen via translocation of seeds or removal of isolation barriers. In this way, it may be an important process in invasion biology where genotypes from various origins are introduced into a new area (Lavergne & Molofsky, 2007). It is also a concern in restoration ecology, where the origin of seed sources used for restoration
Biological invasions may result from multiple introductions, which might compensate for reduced g... more Biological invasions may result from multiple introductions, which might compensate for reduced gene pools caused by bottleneck events, but could also dilute adaptive processes. A previous common-garden experiment showed heritable latitudinal clines in fitness-related traits in the invasive goldenrod Solidago canadensis in Central Europe. These latitudinal clines remained stable even in plants chemically treated with zebularine to reduce epigenetic variation. However, despite the heritability of traits investigated, genetic isolation-by-distance was non-significant. Utilizing the same specimens, we applied a molecular analysis of (epi)genetic differentiation with standard and methylation-sensitive (MSAP) AFLPs. We tested whether this variation was spatially structured among populations and whether zebularine had altered epigenetic variation. Additionally, we used genome scans to mine for putative outlier loci susceptible to selection processes in the invaded range. Despite the absen...
Journal of Sustainable Agriculture and Environment
Introduction: The proximity of semi-natural habitats and agricultural fields in an agricultural l... more Introduction: The proximity of semi-natural habitats and agricultural fields in an agricultural landscape leads to unavoidable biological, chemical, and physical interactions. Fungi can negatively influence, but also support crop growth in agricultural fields. Therefore, in this field study we investigated the colonisation of arbuscular mycorrhizal (AM) fungi and non-AM fungi in winter-wheat roots as well as winter-wheat performance in distance to semi-natural habitats. Materials and Methods: We sampled in an intensively managed agricultural landscape in Northeast Germany along agricultural transition zones, that is, along 50 m-transects from semi-natural habitats like hedgerows and glacially created in-field ponds-so-called kettle holes-into agricultural fields. Results: To our knowledge, we show for the first time that AM fungal colonisation in winterwheat roots decreased linearly with increasing distance to semi-natural habitats while non-AM fungal root colonisation did not change. Winter-wheat grain yield and biomass slightly increased with increasing distance to hedgerows but not to kettle holes. This clearly shows that there is a difference between different crop performance parameters. Random forest machine learning algorithms confirmed the particular importance of distance to semi-natural habitats for AM fungal root colonisation and for winter-wheat grain yield. Less intensive agricultural management close to semi-natural habitats, for example, no herbicide and pesticide applications as a result of nature protection regulations, may partly explain this pattern. However, spatial response patterns of AM but not of non-AM fungi in wheat roots also point to changed ecological interactions close to semi-natural habitats. Conclusion: Semi-natural and natural habitats in agricultural landscapes are slowly recognised not only to be important for biodiversity conservation, but also for sustainable crop production. Additionally, they may also be a tool for farmers and policy makers to improve sustainable landscape management. And agricultural transition zones are spatially and temporally complex dynamic ecosystems that should be the focus of further investigations.
Two rover missions to Mars aim to detect biomolecules as a sign of extinct or extant life with, a... more Two rover missions to Mars aim to detect biomolecules as a sign of extinct or extant life with, among other instruments, Raman spectrometers. However, there are many unknowns about the stability of Raman-detectable biomolecules in the martian environment, clouding the interpretation of the results. To quantify Raman-detectable biomolecule stability, we exposed seven biomolecules for 469 days to a simulated martian environment outside the International Space Station. Ultraviolet radiation (UVR) strongly changed the Raman spectra signals, but only minor change was observed when samples were shielded from UVR. These findings provide support for Mars mission operations searching for biosignatures in the subsurface. This experiment demonstrates the detectability of biomolecules by Raman spectroscopy in Mars regolith analogs after space exposure and lays the groundwork for a consolidated space-proven database of spectroscopy biosignatures in targeted environments.
Plant-associated bacterial assemblages are critical for plant fitness. Thus, identifying a consis... more Plant-associated bacterial assemblages are critical for plant fitness. Thus, identifying a consistent plant-associated core microbiome is important for predicting community responses to environmental changes. Our target was to identify the core bacterial microbiome of orchard grass Dactylis glomerata L. and to assess the part that is most sensitive to land management. Dactylis glomerata L. samples were collected from grassland sites with contrasting land use intensities but comparable soil properties at three different timepoints. To assess the plant-associated bacterial community structure in the compartments rhizosphere, bulk soil and endosphere, a molecular barcoding approach based on high throughput 16S rRNA amplicon sequencing was used. A distinct composition of plant-associated core bacterial communities independent of land use intensity was identified. Pseudomonas, Rhizobium and Bradyrhizobium were ubiquitously found in the root bacterial core microbiome. In the rhizosphere, ...
Interactions between plants and soil microorganisms influence individual plant performance and th... more Interactions between plants and soil microorganisms influence individual plant performance and thus plant-community composition. Most studies on such plant-soil feedbacks (PSFs) have been performed under controlled greenhouse conditions, whereas no study has directly compared PSFs under greenhouse and natural field conditions. We grew three grass species that differ in local abundance in grassland communities simultaneously in the greenhouse and field on field-collected soils either previously conditioned by these species or by the general grassland community. As soils in grasslands are typically conditioned by mixes of species through the patchy and heterogeneous plant species' distributions, we additionally compared the effects of species-specific versus non-specific species conditioning on PSFs in natural and greenhouse conditions. In almost all comparisons PSFs differed between the greenhouse and field. In the greenhouse, plant growth in species-specific and non-specific soi...
BIOMEX (Biology and Mars Experiment) is a space experiment on the exposure platform EXPOSER2 laun... more BIOMEX (Biology and Mars Experiment) is a space experiment on the exposure platform EXPOSER2 launched by the Progress 56 mission on 24 July and placed on the outer side of the Russian Zvezda Module of the International Space Station (ISS). Twenty-five international institutes are working together and sharing different methods, planetary simulation facilities, and logistics to obtain information about the vitality of the tested microorganisms and the stability of biomolecules as possible biosignatures. This experiment comprises three investigational steps from the field to space: (i) field work with sample collection and habitat characterization at field sites with or without Mars analogy, (ii) Mars simulation experiments in the lab and (iii) exposure to real space conditions. For the second and third steps some of the microorganisms and bio-molecules are embedded in Marsanalog regolith mixtures, placed in compartments enriched with Mars-like CO 2 -atmosphere and exposed to solar irradiation levels approaching those affecting the surface of Mars to test habitability on Mars, as well as the ability to detect the selected, Mars-exposed bio-molecules. One of the aims of this experiment is to investigate the specific bio-related spectra of resistant molecules obtained by fluorescence analysis, Raman-spectroscopy, IR- and UV/VIS spectrometry before and after simulated and real space exposure. The obtained database of stable bio-molecules will support future exploration missions to Mars whose main goal is the search for life.
... Analysis of the most productive plots in each treatment at each site (90th quantile) indicate... more ... Analysis of the most productive plots in each treatment at each site (90th quantile) indicates that the 90% confidence intervals for regression slope overlap among all the sites ... Web of Science. We thank A. Hector and the BIODEPTH collaborators for providing us with the data ...
1. One mechanism explaining the success of invasive weeds may be the production and release of al... more 1. One mechanism explaining the success of invasive weeds may be the production and release of allelopathic compounds by the invader that, due to a lack of co-evolutionary history, have harmful effects on plant neighbours in the introduced range. 2. We partially tested this hypothesis by growing seven competing native European plant species either with the introduced Solidago canadensis s.l., one of the most successful invasive plants in Europe or on soil pre-cultivated with S. canadensis. We added activated carbon to the soil to neutralize organic chemical compounds with putative allelopathic effects. Furthermore, we added unsterilized soil inocula from the introduced (Switzerland) or native (USA) range to the soil to test potential confounding effects of soil microbes on invasion success. Untreated sterilized soil served as control. 3. Five out of the seven native species were more competitive against the invasive species in soils with activated carbon than without, supporting the allelopathy hypothesis. However, competitive outcomes were also influenced by the two sources of soil inoculum and by interactive effects of soil inoculum and Solidago origin suggesting that soil microbes alter allelopathic effects. 4. Achillea millefolium , the species least affected by the presence of S. canadensis and with no response to the activated carbon treatment is the only species used in this experiment reported to grow within Solidago stands in Europe, whereas the other European species tested tend to grow at the periphery of invasive Solidago stands. 5. Chemical analysis by LC-MS of Solidago root extracts revealed four main secondary chemical compounds with potential allelopathic effects. Root exudates of Solidago showed a significant inhibitory effect on growth of the model plant species Arabidopsis thaliana. The magnitude of inhibition increased with increasing concentration of the extract. 6. Synthesis. Levels of the four compounds were lower in Solidago populations from the invasive range than in populations of the same ploidy level from the native range. This suggests lower investment of invasive plants into these secondary compounds, possibly because of a higher susceptibility of plant competitors in the invasive range to these substances.
Aims The superior performance of many non-indigenous species in a new range can be attributed to ... more Aims The superior performance of many non-indigenous species in a new range can be attributed to different factors such as pre-adaptation to environmental conditions in new areas or to factors inherent to displacement mechanisms such as loss of co-evolved pathogens and herbivores that increase the speed of evolutionary change towards a shift in allocation from defence to growth and reproduction. To assess the importance of the different mechanisms governing the success of Conyza canadensis, a globally successful invader, we simultaneously tested several recent hypotheses potentially explaining the factors leading to biological invasion. Keywords: allelopathy d biological invasions d Conyza canadensis d EICA hypothesis d generalist/specialist herbivory d latitudinal clines d biogeographic comparison d common garden
Zenodo (CERN European Organization for Nuclear Research), Dec 1, 2020
Abbildung 3: Übersicht der strategischen Handlungsfelder zur Förderung von Biodiversität durch pl... more Abbildung 3: Übersicht der strategischen Handlungsfelder zur Förderung von Biodiversität durch planerische Massnahmen. Illustration: Basil Rüegg Wir haben acht strategische Handlungsfelder identifiziert in Ergänzung zu den konkreten Empfehlungen in den 26 Massnahmenblättern (Anhänge 2 und 3). Die acht Handlungsfelder sind gemäss des Dreisatzes ‚Strategien und Prozesse-Verbindliche & spezifische Vorgaben-Sensibilisierung, Aus-und Weiterbildung & Partizipation, strukturiert. Das dritte Standbein der Sensibilisierung und Bildung erleichtert freiwilliges Engagement und damit die Entwicklung von Leuchtturmprojekten (Abbildung 3): ■ Strategien und Prozesse: Es braucht auf kommunaler, kantonaler und nationaler Ebene eine umfassende strategische Planung zur Erhaltung und Förderung der Biodiversität, der Ökosystemleistungen und der ökologischen Infrastruktur. Dazu sind genügend personelle und finanzielle Mittel erforderlich (Handlungsfeld 1). In einem nächsten Schritt sind fachliche Klärungen zu folgenden Punkten nötig: Integratives Verständnis einer ökologischen und sozialen Landschafts-und Freiraumentwicklung (Handlungsfeld 2), ökologischer Ausgleich als ökologische Aufwertung (Handlungsfeld 3) und die Erweiterung von Zielvorstellungen zur Biodiversität genutzter Landschaften (Handlungsfeld 4).
Anthropogenic changes in climate, land use and disturbance regimes, as well as introductions of n... more Anthropogenic changes in climate, land use and disturbance regimes, as well as introductions of non-native species can lead to the transformation of many ecosystems. The resulting novel ecosystems are usually characterized by species assemblages that have not occurred previously in a given area. Quantifying the ecological novelty of communities (i.e. biotic novelty) would enhance the understanding of environmental change. However, quantification remains challenging since current novelty metrics, such as the number and/or proportion of non-native species in a community, fall
Seed germination and seedling establishment of an invasive tropical tree species under different ... more Seed germination and seedling establishment of an invasive tropical tree species under different climate change scenarios
Böden und die Vielfalt in und auf Böden lebender Organismen sind durch ungezählte Wechselwirkunge... more Böden und die Vielfalt in und auf Böden lebender Organismen sind durch ungezählte Wechselwirkungen verbunden. Akteursgruppen mit unterschiedlichen Interessen nutzen und/oder beeinflussen Böden und Biodiversität auf verschiedene Art und Weise. Sie tun dies-so die These des folgenden Beitrags-überwiegend ohne diesen Wechselwirkungen Rechnung zu tragen und unabhängig voneinander. Damit vergaben sie in der Vergangenheit die Chance, beide Ressourcen wirkungsvoll zu schützen. Welche Ansätze sind potentiell geeignet, den Schutz von Boden und Biodiversität zu verknüpfen? Abstract & Keywords ê p. 239 1) Für die Schweiz siehe [2], für Deutschland siehe [3]. 2) Zu Boden vergleiche [4], Schweizerisches Nationales Forschungsprogramm 22 "Nutzung des Bodens" [5, 6]; zu Biodiversität vergleiche [7-9]. 3) Vergleiche [5] sowie verschiedene Bodenschutzinitiativen von Nichtregierungsorganisationen wie [10] oder die Vorschläge für eine "Bodenkonvention" [6]. 4) Bodenkundliche Gesellschaft Schweiz (BGS). Für die detaillierte Definition siehe Homepage der BGS (www.soil.ch). GAIA 12 (2003) no. 3 Der Baukran rückt näher. Der Boden-und Biodiversitätsschutz ist gefordert, den anhaltend hohen Flächenverbrauch einzudämmen.
Population admixture (hereafter: admixture) is a genetic process of hybridization between previou... more Population admixture (hereafter: admixture) is a genetic process of hybridization between previously isolated populations of one species (Ellstrand & Schierenbeck, 2000). Admixture might, for example, happen via translocation of seeds or removal of isolation barriers. In this way, it may be an important process in invasion biology where genotypes from various origins are introduced into a new area (Lavergne & Molofsky, 2007). It is also a concern in restoration ecology, where the origin of seed sources used for restoration
Biological invasions may result from multiple introductions, which might compensate for reduced g... more Biological invasions may result from multiple introductions, which might compensate for reduced gene pools caused by bottleneck events, but could also dilute adaptive processes. A previous common-garden experiment showed heritable latitudinal clines in fitness-related traits in the invasive goldenrod Solidago canadensis in Central Europe. These latitudinal clines remained stable even in plants chemically treated with zebularine to reduce epigenetic variation. However, despite the heritability of traits investigated, genetic isolation-by-distance was non-significant. Utilizing the same specimens, we applied a molecular analysis of (epi)genetic differentiation with standard and methylation-sensitive (MSAP) AFLPs. We tested whether this variation was spatially structured among populations and whether zebularine had altered epigenetic variation. Additionally, we used genome scans to mine for putative outlier loci susceptible to selection processes in the invaded range. Despite the absen...
Journal of Sustainable Agriculture and Environment
Introduction: The proximity of semi-natural habitats and agricultural fields in an agricultural l... more Introduction: The proximity of semi-natural habitats and agricultural fields in an agricultural landscape leads to unavoidable biological, chemical, and physical interactions. Fungi can negatively influence, but also support crop growth in agricultural fields. Therefore, in this field study we investigated the colonisation of arbuscular mycorrhizal (AM) fungi and non-AM fungi in winter-wheat roots as well as winter-wheat performance in distance to semi-natural habitats. Materials and Methods: We sampled in an intensively managed agricultural landscape in Northeast Germany along agricultural transition zones, that is, along 50 m-transects from semi-natural habitats like hedgerows and glacially created in-field ponds-so-called kettle holes-into agricultural fields. Results: To our knowledge, we show for the first time that AM fungal colonisation in winterwheat roots decreased linearly with increasing distance to semi-natural habitats while non-AM fungal root colonisation did not change. Winter-wheat grain yield and biomass slightly increased with increasing distance to hedgerows but not to kettle holes. This clearly shows that there is a difference between different crop performance parameters. Random forest machine learning algorithms confirmed the particular importance of distance to semi-natural habitats for AM fungal root colonisation and for winter-wheat grain yield. Less intensive agricultural management close to semi-natural habitats, for example, no herbicide and pesticide applications as a result of nature protection regulations, may partly explain this pattern. However, spatial response patterns of AM but not of non-AM fungi in wheat roots also point to changed ecological interactions close to semi-natural habitats. Conclusion: Semi-natural and natural habitats in agricultural landscapes are slowly recognised not only to be important for biodiversity conservation, but also for sustainable crop production. Additionally, they may also be a tool for farmers and policy makers to improve sustainable landscape management. And agricultural transition zones are spatially and temporally complex dynamic ecosystems that should be the focus of further investigations.
Two rover missions to Mars aim to detect biomolecules as a sign of extinct or extant life with, a... more Two rover missions to Mars aim to detect biomolecules as a sign of extinct or extant life with, among other instruments, Raman spectrometers. However, there are many unknowns about the stability of Raman-detectable biomolecules in the martian environment, clouding the interpretation of the results. To quantify Raman-detectable biomolecule stability, we exposed seven biomolecules for 469 days to a simulated martian environment outside the International Space Station. Ultraviolet radiation (UVR) strongly changed the Raman spectra signals, but only minor change was observed when samples were shielded from UVR. These findings provide support for Mars mission operations searching for biosignatures in the subsurface. This experiment demonstrates the detectability of biomolecules by Raman spectroscopy in Mars regolith analogs after space exposure and lays the groundwork for a consolidated space-proven database of spectroscopy biosignatures in targeted environments.
Plant-associated bacterial assemblages are critical for plant fitness. Thus, identifying a consis... more Plant-associated bacterial assemblages are critical for plant fitness. Thus, identifying a consistent plant-associated core microbiome is important for predicting community responses to environmental changes. Our target was to identify the core bacterial microbiome of orchard grass Dactylis glomerata L. and to assess the part that is most sensitive to land management. Dactylis glomerata L. samples were collected from grassland sites with contrasting land use intensities but comparable soil properties at three different timepoints. To assess the plant-associated bacterial community structure in the compartments rhizosphere, bulk soil and endosphere, a molecular barcoding approach based on high throughput 16S rRNA amplicon sequencing was used. A distinct composition of plant-associated core bacterial communities independent of land use intensity was identified. Pseudomonas, Rhizobium and Bradyrhizobium were ubiquitously found in the root bacterial core microbiome. In the rhizosphere, ...
Interactions between plants and soil microorganisms influence individual plant performance and th... more Interactions between plants and soil microorganisms influence individual plant performance and thus plant-community composition. Most studies on such plant-soil feedbacks (PSFs) have been performed under controlled greenhouse conditions, whereas no study has directly compared PSFs under greenhouse and natural field conditions. We grew three grass species that differ in local abundance in grassland communities simultaneously in the greenhouse and field on field-collected soils either previously conditioned by these species or by the general grassland community. As soils in grasslands are typically conditioned by mixes of species through the patchy and heterogeneous plant species' distributions, we additionally compared the effects of species-specific versus non-specific species conditioning on PSFs in natural and greenhouse conditions. In almost all comparisons PSFs differed between the greenhouse and field. In the greenhouse, plant growth in species-specific and non-specific soi...
BIOMEX (Biology and Mars Experiment) is a space experiment on the exposure platform EXPOSER2 laun... more BIOMEX (Biology and Mars Experiment) is a space experiment on the exposure platform EXPOSER2 launched by the Progress 56 mission on 24 July and placed on the outer side of the Russian Zvezda Module of the International Space Station (ISS). Twenty-five international institutes are working together and sharing different methods, planetary simulation facilities, and logistics to obtain information about the vitality of the tested microorganisms and the stability of biomolecules as possible biosignatures. This experiment comprises three investigational steps from the field to space: (i) field work with sample collection and habitat characterization at field sites with or without Mars analogy, (ii) Mars simulation experiments in the lab and (iii) exposure to real space conditions. For the second and third steps some of the microorganisms and bio-molecules are embedded in Marsanalog regolith mixtures, placed in compartments enriched with Mars-like CO 2 -atmosphere and exposed to solar irradiation levels approaching those affecting the surface of Mars to test habitability on Mars, as well as the ability to detect the selected, Mars-exposed bio-molecules. One of the aims of this experiment is to investigate the specific bio-related spectra of resistant molecules obtained by fluorescence analysis, Raman-spectroscopy, IR- and UV/VIS spectrometry before and after simulated and real space exposure. The obtained database of stable bio-molecules will support future exploration missions to Mars whose main goal is the search for life.
... Analysis of the most productive plots in each treatment at each site (90th quantile) indicate... more ... Analysis of the most productive plots in each treatment at each site (90th quantile) indicates that the 90% confidence intervals for regression slope overlap among all the sites ... Web of Science. We thank A. Hector and the BIODEPTH collaborators for providing us with the data ...
Die Förderung der Biodiversität in Agglomerationslandschaften ist ein Fokus des Aktionsplans Stra... more Die Förderung der Biodiversität in Agglomerationslandschaften ist ein Fokus des Aktionsplans Strategie Biodiversität Schweiz (AP SBS). Damit die Biodiversität in Siedlungsräumen langfristig erhalten und gefördert werden kann, braucht es umfassende Anpassungen in der Raumplanung, Siedlungsentwicklung und im Bau. In einer Konzeptstudie zuhanden des BAFU haben wir die ökologischen und planerischen Grundlagen zur Biodiversitätsförderung im Siedlungsraum zusammengestellt (ILF 2020). In diesem Artikel stellen wir aufgrund dieser Studie wichtige Handlungsspielräume der Kantone und Gemeinden zusammen. Es gibt zurzeit ein Window of Opportunity für mehr Natur in unseren Alltagslandschaften. Diese Chancen gilt es zu nutzen: bei Revisionen von kantonalem Gesetz oder kommunalen BZOs ebenso wie bei Wettbewerbsausschreibungen, öffentlichen Bauvorhaben oder in der Öffentlichkeitsarbeit.
La promotion de la biodiversité dans le paysage urbain est l’un des axes du plan d’action de la S... more La promotion de la biodiversité dans le paysage urbain est l’un des axes du plan d’action de la Stratégie Biodiversité Suisse (PA SBS). Pour pouvoir conserver et promouvoir durablement la biodiversité en milieu urbain, des adaptations globales sont nécessaires dans les secteurs de l’aménagement du territoire, de l’urbanisation et de la construction. Dans une étude fondamentale commandée par l’OFEV, nous avons réuni toutes les bases scientifiques et de planification touchant à la promotion de la biodiversité en milieu urbain (ILF 2020). Cet article se fonde sur cette étude afin de montrer que les cantons et les communes disposent d’une marge de manoeuvre importante. Il y a actuellement une fenêtre d’opportunité pour accroître la présence de la nature dans notre quotidien. Il faut en profiter, que ce soit lors de la révision d’une loi cantonale ou du règlement de construction d’une commune, mais aussi lors des concours, des appels d’offres de travaux publics ou encore dans la communication.
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Papers by Jasmin Joshi
de l’aménagement du territoire, de l’urbanisation et de la construction. Dans une étude fondamentale commandée par l’OFEV, nous avons réuni toutes les bases scientifiques et de planification touchant à la promotion de la biodiversité en milieu urbain (ILF 2020). Cet article se fonde sur cette étude afin de montrer que les cantons et les communes disposent d’une marge de manoeuvre importante. Il y a actuellement une fenêtre d’opportunité pour accroître la présence de la nature dans notre quotidien. Il faut en profiter, que ce soit lors de la révision d’une loi cantonale ou du règlement de construction d’une commune, mais aussi lors des concours, des appels d’offres de travaux publics ou encore dans la communication.