Does residence time affect responses of alien species richness to environmental and spatial processes?

One of the most robust emerging generalisations in invasion biology is that the probability of invasion increases with the time since introduction (residence time). We analysed the spatial distribution of alien vascular plant species in a region of north-eastern Italy to understand the influence of residence time on patterns of alien species richness. Neophytes were grouped according to three periods of arrival in the study region (1500–1800, 1800–1900, and > 1900). We applied multiple regression (spatial and nonspatial) with hierarchical partitioning to determine the influence of climate and human pressure on species richness within the groups. We also applied variation partitioning to evaluate the relative importance of environmental and spatial processes. Temperature mainly influenced groups with species having a longer residence time, while human pressure influenced the more recently introduced species, although its influence remained significant in all groups. Partial regression analyses showed that most of the variation explained by the models is attributable to spatially structured environmental variation, while environment and space had small independent effects. However, effects independent of environment decreased, and spatially independent effects increased, from older to the more recent neophytes. Our data illustrate that the distribution of alien species richness for species that arrived recently is related to propagule pressure, availability of novel niches created by human activity, and neutral-based (dispersal limitation) processes, while climate filtering plays a key role in the distribution of species that arrived earlier. This study highlights the importance of residence time, spatial structure, and environmental conditions in the patterns of alien species richness and for a better understanding of its geographical variation

Managing trap-nesting bees as crop pollinators : Spatiotemporal effects of floral resources and antagonists

The decline of managed honeybees and the rapid expansion of mass-flowering crops increase the risk of pollination limitation in crops and raise questions about novel management approaches for wild pollinators in agroecosystems. Adding artificial nesting sites, such as trap nests, can promote cavity-nesting bees in agroecosystems, but effectiveness could be limited by the availability of floral resources in the surrounding landscape and by natural antagonists. In two European regions, we exposed artificial trap nests in paired field boundaries adjacent to oilseed rape (OSR) fields or non-flowering crops for 2 years within 32 landscapes covering two independent gradients of OSR cover and semi-natural habitat (SNH) cover in the landscape. We analysed the effects of local and landscape-wide floral resource availability, land-use intensity, landscape complexity and natural antagonists on community composition and population dynamics of trap-nesting bees. Numbers of brood cells showed a strong, three-fold increase in response to the additional nesting sites. Species richness and abundance of cavity-nesting bees that were active during OSR flowering increased significantly with increasing amounts of early season landscape-wide floral resource availability, such as the cultivation of OSR. Later foraging species benefited instead from the availability of late-season alternative flower resources or SNH cover once the mass-flowering had ceased. Density-dependent parasitism increased following mass-flowering, while no density-dependent effect was found during mass-flowering. Structural equation modelling revealed that the influence of floral resource availability on community growth rate was mediated by community size. Community size showed a strong negative effect on community growth rate. Despite positive density-dependent parasitism, antagonists had only weak regulating effects on community growth rate. Synthesis and applications. Trap-nesting bee populations grow markedly with the increasing availability of food resources in the landscape and effectiveness of trap nests is only marginally limited by natural antagonists. Thus, trap nests could be a simple pollinator-supporting strategy to accompany the current expansion of mass-flowering crops and to ensure pollination services for insect-pollinated crops. Trap nests benefit, not only early season active generalist bees during oilseed rape flowering, but also species with later phenology if accompanied by other pollinator-supporting practices.</p

Plant genetic diversity affects multiple trophic levels and trophic interactions

: Intraspecific genetic diversity is an important component of biodiversity. A substantial body of evidence has demonstrated positive effects of plant genetic diversity on plant performance. However, it has remained unclear whether plant genetic diversity generally increases plant performance by reducing the pressure of plant antagonists across trophic levels for different plant life forms, ecosystems and climatic zones. Here, we analyse 4702 effect sizes reported in 413 studies that consider effects of plant genetic diversity on trophic groups and their interactions. We found that that increasing plant genetic diversity decreased the performance of plant antagonists including invertebrate herbivores, weeds, plant-feeding nematodes and plant diseases, while increasing the performance of plants and natural enemies of herbivores. Structural equation modelling indicated that plant genetic diversity increased plant performance partly by reducing plant antagonist pressure. These results reveal that plant genetic diversity often influences multiple trophic levels in ways that enhance natural pest control in managed ecosystems and consumer control of plants in natural ecosystems for sustainable plant production

Exploring patterns of beta‐diversity to test the consistency of biogeographical boundaries: A case study across forest plant communities of Italy

Aim To date, despite their great potential biogeographical regionalization models have been mostly developed on descriptive and empirical bases. This paper aims at applying the beta-diversity framework on a statistically representative data set to analytically test the consistency of the biogeographical regionalization of Italian forests. Location Italy. Taxon Vascular plants. Methods Forest plant communities were surveyed in 804 plots made in a statistically representative sample of forest communities made by 201 sites of Italian forests across the three biogeographical regions of the country: Alpine, Continental, and Mediterranean. We conducted an ordination analysis and an analysis of beta-diversity, decomposing it into its turnover and nestedness components. Results Our results provide only partial support to the consistency of the biogeographical regionalization of Italy. While the differences in forest plant communities support the distinction between the Alpine and the other two regions, differences between Continental and Mediterranean regions had lower statistical support. Pairwise beta-diversity and its turnover component are higher between- than within-biogeographical regions. This suggests that different regional species pools contribute to assembly of local communities and that spatial distance between-regions has a stronger effect than that within-regions. Main conclusions Our findings confirm a biogeographical structure of the species pools that is captured by the biogeographical regionalization. However, nonsignificant differences between the Mediterranean and Continental biogeographical regions suggest that this biogeographical regionalization is not consistent for forest plant communities. Our results demonstrate that an analytical evaluation of species composition differences among regions using beta-diversity analysis is a promising approach for testing the consistency of biogeographical regionalization models. This approach is recommended to provide support to the biogeographical regionalization used in some environmental conservation polices adopted by EU

When instrument location makes the difference on rainfall thresholds definition: Lessons learned at Cancia, Dolomites

Since debris flows represent one of the most dangerous natural hazard in mountain areas, Early Warning Systems (EWSs) play a crucial role in reducing the risk of these hazardous processes. Robust event pre-alert usually relies on long time series of local rainfall measures. Oftentimes regional rain gauge networks present an insufficient spatial density to grasp the highly variable spatio-temporal dynamics of debris-flow triggering events and thus relying on such networks for developing rainfall thresholds might lead to relatively low rainfall estimates. The present paper reports the development of operational rainfall thresholds for the Cancia EWS, Dolomites (NE Italy). The instrumentation configuration led to the derivation and implementation of a set of rainfall thresholds that significantly enhanced pre-alarm reliability thanks to an optimal spatial distribution of multiple rain gauges within the catchment. Notwithstanding the small number of debris flows occurred during the calibration period, rainfall thresholds were derived considering the whole population of rainfall events showcasing the statistical properties of those events that led to debris-flow initiation. Finally, the validation period served as proof of work for the proposed thresholds with no raised false alarms and with the identification of few minor, but correctly detected, debris flows

Experimental and Numerical Analysis of a Non-Newtonian Fluids Processing Pump

Abstract Centrifugal pumps are used in many applications in which non-Newtonian fluids are involved: food processing industry, pharmaceutical and oil/gas applications. In addition to pressure and temperature, the viscosity of a non-Newtonian fluid depends on the shear rate and usually is several orders of magnitude higher than water. High values of viscosity cause a derating of pump performance with respect to water. Nowadays, pumping and mixing non-Newtonian fluids is a matter of increasing interest, but there is still lack of a detailed analysis of the fluid-dynamic phenomena occurring within these machines. A specific design process should take into account these effects in order to define the proper pump geometry, able to operate with non-Newtonian fluids with specific characteristics. Only few approaches are available for correcting the pump performance based on the Hydraulic Institute method. In this work, an experimental and numerical campaign is presented for a semi–open impeller centrifugal pump elaborating non-Newtonian fluids. An on-purpose test bench was built and used to investigate the influence on pump performance of three different non-Newtonian fluids. Each pump performance test was accompanied by the rheological characterization of the fluid, in order to detect modifications of the rheological phenomena and allow a proper Computation Fluid Dynamics (CFD) modeling. The performance of the machine handling both Newtonian and non-Newtonian fluids are highlighted in relation with the internal flow field

A global synthesis reveals biodiversity-mediated benefits for crop production

Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield–related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.EEA ConcordiaFil: Dainese, Matteo. Eurac Research. Institute for Alpine Environment; ItaliaFil: Dainese, Matteo. University of Würzburg. Biocenter. Department of Animal Ecology and Tropical Biology; AlemaniaFil: Martin, Emily A. University of Würzburg. Biocenter. Department of Animal Ecology and Tropical Biology; AlemaniaFil: Aizen, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Aizen, Marcelo Adrian. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Albrecht, Matthias. Agroscope. Agroecology and Environment; SuizaFil: Bartomeus, Ignasi. CSIC. Estación Biológica de Doñana. Integrative Ecology; EspañaFil: Bommarco, Riccardo. Swedish University of Agricultural Sciences. Department of Ecology; SueciaFil: Carvalheiro, Luisa G. Universidade Federal de Goias. Departamento de Ecologia; BrasilFil: Carvalheiro, Luisa G. Universidade de Lisboa. Faculdade de Ciencias. Centre for Ecology, Evolution and Environmental Changes (CE3C); PortugalFil: Chaplin-Kramer, Rebecca. Stanford University. Natural Capital Project; Estados UnidosFil: Gagic, Vesna. Commonwealth Scientific and Industrial Research Organisation (CSIRO); AustraliaFil: Garibaldi, Lucas Alejandro. Universidad Nacional de Rio Negro. Instituto de Investigaciones de Recursos Naturales, Agroecología y Desarrollo Rural; ArgentinaFil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cavigliasso, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; ArgentinaFil: Steffan-Dewenter, Ingolf. University of Würzburg. Biocenter. Department of Animal Ecology and Tropical Biology; Alemani

Understanding the pathways from biodiversity to agro-ecological outcomes: A new, interactive approach

The adoption of agro-ecological practices in agricultural systems worldwide can contribute to increased food production without compromising future food security, especially under the current biodiversity loss and climate change scenarios. Despite the increase in publications on agro-ecological research and practices during the last 35 years, a weak link between that knowledge and changed farmer practices has led to few examples of agro-ecological protocols and effective delivery systems to agriculturalists. In an attempt to reduce this gap, we synthesised the main concepts related to biodiversity and its functions by creating a web-based interactive spiral (www.biodiversityfunction.com). This tool explains and describes a pathway for achieving agro-ecological outcomes, starting from the basic principle of biodiversity and its functions to enhanced biodiversity on farms. Within this pathway, 11 key steps are identified and sequentially presented on a web platform through which key players (farmers, farmer networks, policy makers, scientists and other stakeholders) can navigate and learn. Because in many areas of the world the necessary knowledge needed for achieving the adoption of particular agro-ecological techniques is not available, the spiral approach can provide the necessary conceptual steps needed for obtaining and understanding such knowledge by navigating through the interactive pathway. This novel approach aims to improve our understanding of the sequence from the concept of biodiversity to harnessing its power to improve prospects for ‘sustainable intensification’ of agricultural systems worldwide

Models of natural pest control : Towards predictions across agricultural landscapes

Natural control of invertebrate crop pests has the potential to complement or replace conventional insecticide based practices, but its mainstream application is hampered by predictive unreliability across agroecosystems. Inconsistent responses of natural pest control to changes in landscape characteristics have been attributed to ecological complexity and system-specific conditions. Here, we review agroecological models and their potential to provide predictions of natural pest control across agricultural landscapes. Existing models have used a multitude of techniques to represent specific crop-pest-enemy systems at various spatiotemporal scales, but less wealthy regions of the world are underrepresented. A realistic representation of natural pest control across systems appears to be hindered by a practical trade-off between generality and realism. Nonetheless, observations of context-sensitive, trait-mediated responses of natural pest control to land-use gradients indicate the potential of ecological models that explicitly represent the underlying mechanisms. We conclude that modelling natural pest control across agroecosystems should exploit existing mechanistic techniques towards a framework of contextually bound generalizations. Observed similarities in causal relationships can inform the functional grouping of diverse agroecosystems worldwide and the development of the respective models based on general, but context-sensitive, ecological mechanisms. The combined use of qualitative and quantitative techniques should allow the flexible integration of empirical evidence and ecological theory for robust predictions of natural pest control across a wide range of agroecological contexts and levels of knowledge availability. We highlight challenges and promising directions towards developing such a general modelling framework.Peer reviewe

Pathology Laboratory Archives: Conservation Quality of Nucleic Acids and Proteins for NSCLC Molecular Testing

In the molecular era, proper archival conditions within pathology laboratories are crucial, especially for formalin-fixed paraffin-embedded (FFPE) tissue specimens retrieved years after the original diagnosis. Indeed, improper preservation can impact the integrity of nucleic acids and protein antigens. This study evaluates the quality status of stored FFPE blocks using multilevel omics approaches. FFPE blocks from 45 Non-Small Cell Lung Carcinoma (NSCLC) cases were analyzed. The blocks were collected from six different pathology archives across Italy with distinct environmental characteristics. Nucleic acids’ quantity and quality, as well as protein antigens, were assessed using various techniques, including MALDI-MSI. RNA was quantitatively higher, but more fragmented, compared to DNA. DNA quantity and quality were suitable for molecular analyses in 94.4% and 62.3% of samples, respectively. RNA quantity was adequate across all samples, but it was optimal only in 22.3% of cases. DNA quality started to deteriorate after 6–8 years, whereas RNA quality diminished only after 10 years of storage. These data might suggest a particular DNA susceptibility to FFPE blocks conservation. Immunohistochemical intensity decreased significantly after 6–8 years of storage, and MALDI-MSI analysis revealed that younger tissue blocks contained more unique proteomic signals than the older ones. This study emphasizes the importance of proper FFPE archiving conditions for molecular analyses. Governance should prioritize attention to pathology archives to ensure quality preservation and optimize predictive testing. By elucidating the nuances of FFPE block storage, this research paves the way for enhanced molecular diagnostics and therapeutic insights regarding oncology and beyond