Palladium nanoparticles on modified cellulose as a novel catalyst for low temperature gas reactions

Palladium was incorporated into carboxymethylated cellulose fibers as a support, thereby becoming an efficient and stable catalyst for low temperature gas phase reaction. Thus, NO was used as test molecule of Greenhouse Gas to be catalytically reduced with hydrogen on an eco-friendly sustainable material containing palladium as the active site. Prior to the catalytic test, the catalysts were reduced with glucose as an eco-friendly reagent. The material characterization was performed by SEM–EDS, XRD, LRS, TGA and FTIR. The catalytic results showed that at 170 °C, NO conversion was 100% with a selectivity of 70% to nitrogen. While NOX species were completely converted into N2 at temperatures higher than 180 °C. The starting commercial dissolving pulp was also studied, but its performance resulted lower than the ones of functionalized fibers. The use of this strategy, i.e., the functionalization of cellulose fibers followed by in-situ formation of metallic nanoparticles, can be further applied for the design of a wide range of materials with interesting applications for gas and liquid phase reactions under mild conditions.Fil: Gioria, Esteban Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Signorini, Chiara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Taleb, María Claudia. Universidad Nacional del Litoral; ArgentinaFil: Thomas, Arne. Technishe Universitat Berlin; AlemaniaFil: Mihályi, Magdolna R.. No especifíca;Fil: Gutierrez, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Understorey plant community composition reflects its invasion history decades after invasive Rhododendron ponticum has been removed

This research was funded by Scottish Natural Heritage, project reference 014299. We would additionally like to thank all the landowners who provided access to their land for this study.Peer reviewedPostprintPostprin

When is the Best Time to Sample Aquatic Macroinvertebrates in Ponds for Biodiversity Assessment?

Ponds are sites of high biodiversity and conservation value, yet there is little or no statutory monitoring of them across most of Europe. There are clear and standardized protocols for sampling aquatic macroinvertebrate communities in ponds but the most suitable time(s) to undertake the survey(s) remains poorly specified. This paper examined the aquatic macroinvertebrate communities from 95 ponds within different landuse types over three seasons (spring, summer and autumn) to determine the most appropriate time to undertake sampling to characterise biodiversity. The combined samples from all three seasons provided the most comprehensive record of the aquatic macroinvertebrate taxa recorded within ponds (alpha and gamma diversity). Samples collected during the autumn survey yielded significantly greater macroinvertebrate richness (76% of the total diversity) than either spring or summer surveys. Macroinvertebrate diversity was greatest during autumn in meadow and agricultural ponds but taxon richness among forest and urban ponds did not differ significantly temporally. The autumn survey provided the highest measures of richness for Coleoptera, Hemiptera and Odonata. However, richness of the aquatic insect order Trichoptera was highest in spring and lowest in autumn. The results illustrate that multiple surveys, covering more than one season, provide the most comprehensive representation of macroinvertebrate biodiversity. When sampling can only be undertaken on one occasion, the most appropriate time to undertake surveys to characterise the macroinvertebrate community biodiversity is during the autumn; although this may need to be modified if other floral and faunal groups need to be incorporated in to the sampling programme

The value of plantation forests for plant, invertebrate and bird diversity and the potential for cross-taxon surrogacy

As the area of plantation forest expands worldwide and natural, unmanaged forests decline there is much interest in the potential for planted forests to provide habitat for biodiversity. In regions where little semi-natural woodland remains, the biodiversity supported by forest plantations, typically non-native conifers, may be particularly important. Few studies provide detailed comparisons between the species diversity of native woodlands which are being depleted and non-native plantation forests, which are now expanding, based on data collected from multiple taxa in the same study sites. Here we compare the species diversity and community composition of plants, invertebrates and birds in Sitka spruce- (Picea sitchensis-) dominated and Norway spruce- (Picea abies-) dominated plantations, which have expanded significantly in recent decades in the study area in Ireland, with that of oak- and ash-dominated semi-natural woodlands in the same area. The results show that species richness in spruce plantations can be as high as semi-natural woodlands, but that the two forest types support different assemblages of species. In areas where non-native conifer plantations are the principle forest type, their role in the provision of habitat for biodiversity conservation should not be overlooked. Appropriate management should target the introduction of semi-natural woodland characteristics, and on the extension of existing semi-natural woodlands to maintain and enhance forest species diversity. Our data show that although some relatively easily surveyed groups, such as vascular plants and birds, were congruent with many of the other taxa when looking across all study sites, the similarities in response were not strong enough to warrant use of these taxa as surrogates of the others. In order to capture a wide range of biotic variation, assessments of forest biodiversity should either encompass several taxonomic groups, or rely on the use of indicators of diversity that are not species based

Persistent soil seed banks promote naturalisation and invasiveness in flowering plants

With globalisation facilitating the movement of plants and seeds beyond the native range, preventing potentially harmful introductions requires knowledge of what drives the successful establishment and spread of alien plants. Here, we examined global-scale relationships between naturalisation success (incidence and extent) and invasiveness, soil seed bank properties (type and densities) and key species traits (seed mass, seed dormancy and life form) for 2350 species of angiosperms. Naturalisation and invasiveness were strongly associated with the ability to form persistent (vs. transient) seed banks but relatively weakly with seed bank densities and other traits. Our findings suggest that seed bank persistence is a trait that better captures the ability to become naturalised and invasive compared to seed traits more widely available in trait databases. Knowledge of seed persistence can contribute to our ability to predict global naturalisation and invasiveness and to identify potentially invasive flowering plants before they are introduced