832 results on '"Sergio Rossi"'
Search Results
2. Reassessing the schedule of the sugar season in maple under climate warming
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Gian de Lima Santos, Roberto Silvestro, Sara Yumi Sassamoto Kurokawa, Guillaume de Lafontaine, and Sergio Rossi
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maple syrup ,Acer saccharum ,sap exudation ,freeze-thaw cycles ,climate change ,Agriculture ,Plant culture ,SB1-1110 - Abstract
Daily temperature fluctuations trigger physical and metabolic processes in the xylem, affecting the timing and yield of maple sap production. This study evaluates sap production dynamics, examining the effects of mean monthly temperatures and freeze-thaw cycles before and during the sugar season. We developed a predictive model estimating sap phenology, i.e. the timings of sap season and their climatic drivers, under future warming scenarios in Quebec, Canada. We collected air temperatures and daily sap production at four study sites in 2022 and 2023 using rain gauges for simulating a gravity collection of sap. We estimated sap phenology using a neural network model based on average monthly temperatures. The length of the sugar season was consistent across and within sites, with the highly productive days showing similar occurrence across sites. Sap yields ranged from 9.28 to 23.8 liters in 2022 and 3.8 to 13.6 liters in 2023. Freeze-thaw events occurred on 64% of the days when sap was exuded. Our neural network model predicted that a 2°C increase in mean monthly temperatures would advance the sugar season start by 17 days and end by 13 days. Any mismatch between tapping and favorable weather conditions can significantly reduce sap production. With climate change, producers will be forced to progressively readjust the schedule of their field activities and tapping to match the shifting sugar season.
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- 2025
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3. Partial asynchrony of coniferous forest carbon sources and sinks at the intra-annual time scale
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Roberto Silvestro, Maurizio Mencuccini, Raúl García-Valdés, Serena Antonucci, Alberto Arzac, Franco Biondi, Valentina Buttò, J. Julio Camarero, Filipe Campelo, Hervé Cochard, Katarina Čufar, Henri E. Cuny, Martin de Luis, Annie Deslauriers, Guillaume Drolet, Marina V. Fonti, Patrick Fonti, Alessio Giovannelli, Jožica Gričar, Andreas Gruber, Vladimír Gryc, Rossella Guerrieri, Aylin Güney, Xiali Guo, Jian-Guo Huang, Tuula Jyske, Jakub Kašpar, Alexander V. Kirdyanov, Tamir Klein, Audrey Lemay, Xiaoxia Li, Eryuan Liang, Anna Lintunen, Feng Liu, Fabio Lombardi, Qianqian Ma, Harri Mäkinen, Rayees A. Malik, Edurne Martinez del Castillo, Jordi Martinez-Vilalta, Stefan Mayr, Hubert Morin, Cristina Nabais, Pekka Nöjd, Walter Oberhuber, José M. Olano, Andrew P. Ouimette, Teemu V. S. Paljakka, Mikko Peltoniemi, Richard L. Peters, Ping Ren, Peter Prislan, Cyrille B. K. Rathgeber, Anna Sala, Antonio Saracino, Luigi Saulino, Piia Schiestl-Aalto, Vladimir V. Shishov, Alexia Stokes, Raman Sukumar, Jean-Daniel Sylvain, Roberto Tognetti, Václav Treml, Josef Urban, Hanuš Vavrčík, Joana Vieira, Georg von Arx, Yan Wang, Bao Yang, Qiao Zeng, Shaokang Zhang, Emanuele Ziaco, and Sergio Rossi
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Science - Abstract
Abstract As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels.
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- 2024
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4. Sugar Maple and Red Maple Face-Off: Which Produces More and Sweeter Sap?
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Aya Garfa, Roberto Silvestro, Sara Yumi Sassamoto Kurokawa, Sergio Rossi, Annie Deslauriers, and Serge Lavoie
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maple sap ,sugar maple ,red maple ,sap production ,timing of the sap season ,sugar content ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Among the species used for syrup production, sugar maple (Acer saccharum Marsh.) is preferred by producers, while red maple (Acer rubrum L.) is considered less productive in terms of sap yield and sugar content. This study aims to measure the volume and physicochemical characteristics of the sap produced from two red maples and two sugar maples during the 2023 sugar season in a commercial sugarbush in Laterrière (QC, Canada). Sap exudation was measured continuously with the gravity method using automatic rain gauges. Sap production was discontinuous and heterogeneous, reaching 2.6 L during the most productive day. No significant difference was found in the daily production between species, but we observed a difference in the cumulative sap production (7 L in red maple vs. 13.5 L in sugar maple) due to a longer period of sap exudation in the latter. Despite daily variations in pH, Brix values, sucrose concentration, osmolality, and conductivity, no differences in physicochemical characteristics were detected between species.
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- 2025
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5. Growth Rate and Not Growing Season Explains the Increased Productivity of Masson Pine in Mixed Stands
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Chunmei Bai, Wendi Zhao, Marcin Klisz, Sergio Rossi, Weijun Shen, and Xiali Guo
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subtropical forest ,overyielding ,mixing effect ,unevenly aged stands ,xylem formation ,Pinus massoniana ,Botany ,QK1-989 - Abstract
Increased tree species diversity can promote forest production by reducing intra-specific competition and promoting an efficient unitization of resources. However, questions remain on whether and how mixed stands affect the dynamics of intra–annual xylem formation in trees, especially in subtropical forests. In this study, we randomly selected 18 trees from a monoculture of 63-year-old Masson pine (Pinus massoniana) growing in pure stands and mixed them with 39-year-old Castanopsis hystrix in Pinxiang, southern China. A total of 828 microcores were collected biweekly throughout the growing season from 2022 to 2023 to monitor the intra-annual xylem formation. Cell production started in early March and ended in late December and lasted about 281 to 284 days. Xylem phenology was similar between mixed and pure stands. During both seasons, the Masson pine in mixed stands showed higher xylem production and growth rates than those in pure stands. The Masson pine in mixed stands produced 45–51 cells in 2022 (growth rate of 0.22 cells day−1) and 35–41 cells in 2023 (0.17 cells day−1). Growth rate, and not growth seasons, determined the superior xylem growth in the mixed stands. Our study shows that after 39 years of management, Masson pine and C. hystrix unevenly aged mixed stands have a significant positive mixing effect on Masson pine xylem cell production, which demonstrates that monitoring intra-annual xylem growth dynamics can be an important tool to evaluate the effect of species composition and reveal the mechanisms to promote tree growth behind the mixing effect.
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- 2025
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6. Stable Isotopes Analysis of Bioremediating Organisms in an Innovative Integrated Multi-Trophic Aquaculture System
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Jacopo Borghese, Adriana Giangrande, Daniele Arduini, Lorenzo Doria, Caterina Longo, Lucia Rizzo, Antonio Pennetta, Giuseppe E. De Benedetto, and Sergio Rossi
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isotopic signature ,filter feeders ,mariculture ,Integrated Multi-Trophic Aquaculture ,bioremediation ,Mediterranean Sea ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
Integrated Multi-Trophic Aquaculture (IMTA) has been demonstrated to be a very useful tool to minimize the waste product production of fish monocultures whilst promoting biomass that can be used for different purposes. The stable isotope analysis (δ13C, δ15N, and C:N ratio) of bioremediating organisms present in an IMTA facility is critical to understanding the nutrient flow between farm food waste and filter-feeding organisms, and hence the bioremediation capability of the IMTA system. Here, we report the isotopic signature of the sediment below the fish cages, the fish artificial food and sixteen different suspension feeding species present in the IMTA system in the Mar Grande of Taranto (Italy). A comparison of the stable isotopes results of the bioremediating organisms with those of the same species collected from a control (Cnt) site, unaffected by the plant discharges, was thus conducted looking for trophic level patterns. This assessment aimed to evaluate the possible influence of aquaculture waste on the diet of the organisms, revealing these findings for the first time. Similar δ15N values (below 2–3‰ between areas) were found between the IMTA and Cnt sites, while differences in δ13C values were found among multiple organisms between the two sites, suggesting a possible different primary source of the organic matter that supports the trophic web. Almost all analyzed species in the IMTA site reported δ13C values lower than Cnt site, being more similar to the isotopic signature of the aquaculture finfish food. However, the wide IMTA isotopic range for both δ15N and δ13C suggested a broad spectrum of diets for bioremediating organisms that can actively mitigate the impacts of mariculture by capturing different particles and using various food sources, leading to more sustainable mariculture activities.
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- 2024
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7. Editorial: Vegetation-based degradation and restoration on the alpine grasslands of the Tibetan plateau
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Yujie Niu, Yanfu Bai, and Sergio Rossi
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vegetation classification ,disturbance ,land degradation ,climate change ,plant-soil interactions ,Plant culture ,SB1-1110 - Published
- 2024
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8. Microplastics determination and quantification in two benthic filter feeders Sabella spallanzanii, Polychaeta and Paraleucilla magna, Porifera
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Giuseppe E. De Benedetto, Silvia Fraissinet, Nicoletta Tardio, Sergio Rossi, and Cosimino Malitesta
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Microplastics ,Benthos ,Filter-feeder ,Multi-reagent digestion ,Mariculture ,Pollution monitoring ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Plastic pollution is a worldwide problem especially in the marine environment. Plastic items once fragmented into microplastics (MPs), can be captured by different marine species. Benthic filter feeders like sponges and polychaetas, due to their trophic strategy, are highly exposed to MPs pollution. Herein a simple but effective method to digest the fan worm Sabella spallanzanii and the calcareous sponge Paraleucilla magna is presented: a solution with KOH and H2O2 was able to remove quantitatively (more than 98 %) the organic matter in 3 h while an acid treatment dissolved most of spicules and chaetes in less than 30 min. MPs were easily identified both microscopically and spectroscopically on filters. Quantification in animals collected from the same environment showed that, on average, sponges accumulate fewer MPs than polychaetes (66 ± 31 and 117 ± 46 particles/g dry weight, respectively). The plastic recovery of the method was validated using three different approaches (spiking of standard PS microspheres, of common-use plastic objects, and of microplastics already weathered in marine environment). This procedure can make it easier and cost-effective to process biota in monitoring studies, providing information about bioindicator/bioremediation species.
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- 2024
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9. Trophic ecology of Angolan cold-water coral reefs (SE Atlantic) based on stable isotope analyses
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Beatriz Vinha, Sergio Rossi, Andrea Gori, Ulrike Hanz, Antonio Pennetta, Giuseppe E. De Benedetto, Furu Mienis, Veerle A. I. Huvenne, Dierk Hebbeln, Claudia Wienberg, Jürgen Titschack, André Freiwald, Stefano Piraino, and Covadonga Orejas
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Medicine ,Science - Abstract
Abstract Cold-water coral (CWC) reefs of the Angolan margin (SE Atlantic) are dominated by Desmophyllum pertusum and support a diverse community of associated fauna, despite hypoxic conditions. In this study, we use carbon and nitrogen stable isotope analyses (δ13C and δ15N) to decipher the trophic network of this relatively unknown CWC province. Although fresh phytodetritus is available to the reef, δ15N signatures indicate that CWCs (12.90 ± 1.00 ‰) sit two trophic levels above Suspended Particulate Organic Matter (SPOM) (4.23 ± 1.64 ‰) suggesting that CWCs are highly reliant on an intermediate food source, which may be zooplankton. Echinoderms and the polychaete Eunice norvegica occupy the same trophic guild, with high δ13C signatures (-14.00 ± 1.08 ‰) pointing to a predatory feeding behavior on CWCs and sponges, although detrital feeding on 13C enriched particles might also be important for this group. Sponges presented the highest δ15N values (20.20 ± 1.87 ‰), which could be due to the role of the sponge holobiont and bacterial food in driving intense nitrogen cycling processes in sponges’ tissue, helping to cope with the hypoxic conditions of the reef. Our study provides first insights to understand trophic interactions of CWC reefs under low-oxygen conditions.
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- 2023
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10. Microplastics Uptake by Four Filter Feeders
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Silvia Fraissinet, Daniele Arduini, Alessandra Martines, Giuseppe Egidio De Benedetto, Cosimino Malitesta, Adriana Giangrande, and Sergio Rossi
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microplastics ,bioremediation ,IMTA ,filter feeders ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
Microplastics (MPs) are insidious plastic particles with sizes ranging from 1 to 5000 µm. Their presence has been reported all over the world. Recently, bioremediation to remove MPs from water columns using filter feeders as biofilters has been proposed. In a previous lab experiment, the MP bioremediation potential of four fouling organisms from a mariculture facility (Mytilus galloprovincialis, Sabella spallanzanii, Phallusia mammillata, Paraleucilla magna) was separately assessed in single-species experiment. Herein, a follow-up of the work is presented using a multi-species approach. The four organisms were placed together in the same 5 L beaker and fed with a concentration of 250 p/L 6 µm red polystyrene discernible particles. After digesting the organisms and counting the MPs in both the water and the organisms, the results of the two experiments were compared. In the previous experiment, S. spallanzanii had the highest particle retention (PR) value (PR = 88.01%), while in this experiment, P. mammillata has the lowest PR value (PR = 31%). The multi-species approach resulted in a higher number of plastics being removed from the water (88%) compared to the single-species experiments. These fouling organisms naturally exist as a community, acting as an efficient filter with complex morphologies and hydrodynamic features. Here, this simple marine animal forest is re-evaluated by exploiting the ecosystem services provided by these organisms as a solution to MP pollution problem in a mariculture environment.
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- 2024
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11. Inland populations of sugar maple manifest higher phenological plasticity than coastal populations
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Yongzhi Zhou, Chunmei Bai, Xiali Guo, Vasyl Mohytych, Marcin Klisz, Sylvain Delagrange, and Sergio Rossi
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Acer saccharum ,bud burst ,common garden ,climate change ,temperature ,Evolution ,QH359-425 ,Ecology ,QH540-549.5 - Abstract
Plasticity is vital for plants to rapidly acclimate to environmental changes, especially under the climate change. Global warming could advance bud break and extend the growing season, but it also increases the risk of frost damage to developing leaves. In this study, we explored the phenological plasticity of bud burst of half-sib family sugar maple (Acer saccharum Marsh.) seedlings from 11 seed origins in two common gardens at the center and the northern edge of the species distribution in Quebec, Canada. Results showed that the phenological plasticity of sugar maple originating from inland was significantly higher than those from coastal areas at the beginning of leaf development. This discrepancy may result from the long-term frost change frequency of seed origins. Our study suggests that in the context of climate warming, the higher plasticity observed in sugar maple originating from inland areas may benefit from the phenological adaptation of sugar maple and the survival of local populations. It also suggests that inland populations may have a higher potential regarding to assisted migration, but this needs to be confirmed for other functional traits than phenology.
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- 2023
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12. Recoverable and reusable heterogeneous yttrium triflate for michael and diels-alder additions
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Emanuela Donato, Fabrizio Medici, Valerio Chiroli, Sergio Rossi, and Alessandra Puglisi
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Chemistry ,QD1-999 - Published
- 2023
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13. Autumn canopy senescence has slowed down with global warming since the 1980s in the Northern Hemisphere
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Yichen Zhang, Songbai Hong, Qiang Liu, Chris Huntingford, Josep Peñuelas, Sergio Rossi, Ranga B. Myneni, and Shilong Piao
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Geology ,QE1-996.5 ,Environmental sciences ,GE1-350 - Abstract
Abstract Climate change strongly impact vegetation phenology, with considerable potential to alter land-atmosphere carbon dioxide exchange and terrestrial carbon cycle. In contrast to well-studied spring leaf-out, the timing and magnitude of autumn senescence remains poorly understood. Here, we use monthly decreases in Normalized Difference Vegetation Index satellite retrievals and their trends to surrogate the speed of autumn senescence during 1982–2018 in the Northern Hemisphere (>30°N). We find that climate warming accelerated senescence in July, but this influence usually reversed in later summer and early autumn. Interestingly, summer greening causes canopy senescence to appear later compared to an advancing trend after eliminating the greening effect. This finding suggests that summer canopy greening may counteract the intrinsic changes in autumnal leaf senescence. Our analysis of autumn vegetation behavior provides reliable guidance for developing and parameterizing land surface models that contain an interactive dynamic vegetation module for placement in coupled Earth System Models.
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- 2023
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14. A longer wood growing season does not lead to higher carbon sequestration
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Roberto Silvestro, Qiao Zeng, Valentina Buttò, Jean-Daniel Sylvain, Guillaume Drolet, Maurizio Mencuccini, Nelson Thiffault, Shaoxiong Yuan, and Sergio Rossi
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Medicine ,Science - Abstract
Abstract A reliable assessment of forest carbon sequestration depends on our understanding of wood ecophysiology. Within a forest, trees exhibit different timings and rates of growth during wood formation. However, their relationships with wood anatomical traits remain partially unresolved. This study evaluated the intra-annual individual variability in growth traits in balsam fir [Abies balsamea (L.) Mill.]. We collected wood microcores weekly from April to October 2018 from 27 individuals in Quebec (Canada) and prepared anatomical sections to assess wood formation dynamics and their relationships with the anatomical traits of the wood cells. Xylem developed in a time window ranging from 44 to 118 days, producing between 8 and 79 cells. Trees with larger cell production experienced a longer growing season, with an earlier onset and later ending of wood formation. On average, each additional xylem cell lengthened the growing season by 1 day. Earlywood production explained 95% of the variability in xylem production. More productive individuals generated a higher proportion of earlywood and cells with larger sizes. Trees with a longer growing season produced more cells but not more biomass in the wood. Lengthening the growing season driven by climate change may not lead to enhanced carbon sequestration from wood production.
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- 2023
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15. Twin‐Wire Sensor Networks
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Sergio Rossi, Nerio Andrés Montoya, and Christian Falconi
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4‐wire measurements ,array of resistive sensors ,array of temperature sensors ,high‐density sensing ,twin‐wire sensor networks ,Technology (General) ,T1-995 ,Science - Abstract
Abstract A fundamental limit to high‐density sensing is that adding sensors increases the number of wires, pads, and interconnections. This problem is even worse for low‐values resistive or impedance sensors which, for high accuracy, require 4‐wire measurements. Here, twin‐wire sensor networks are described which enable 4‐wire measurements with significantly fewer wires, pads, and interconnections. The effects of the resistor noise can be minimized by minimum‐resistance sensing paths. A single chopper switch and straightforward digital operations can reject the equivalent input offset and low‐frequency noise voltages of the instrumentation amplifier, thus requiring no hardware changes. The inclusion in the network of a reference resistor can compensate the errors of both the biasing current and the instrumentation amplifier voltage gain. For validation, an extremely compact, robust, and easy‐to‐connect flexible‐PCB twin‐wire 29‐temperature‐sensors network requiring only 32 pads is demonstrated. This device is placed on an anthropomorphic head phantom for detecting the temperature and location of a touching object or on the hand of a volunteer for monitoring skin temperature during mental and physical stimulations. A twin‐wire 29‐photoresistors network is also presented. The strategies reported here can be applied to any high‐density array of resistive or impedance sensors (temperature, strain, blood flow, light, etc.) and may find wide application in robotics and wearable or epidermal devices.
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- 2023
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16. Marine Animal Forests of the World: Definition and Characteristics
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Covadonga Orejas, Marina Carreiro-Silva, Christian Mohn, James Reimer, Toufiek Samaai, A. Louise Allcock, and Sergio Rossi
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Marine Animal Forest ,structural role ,functionali ,Science - Abstract
The term Marine Animal Forest (MAF) was first described by Alfred Russel Wallace in his book “The Malay Archipelago” in 1869. The term was much later re-introduced and various descriptions of MAFs were presented in great detail as part of a book series. The international research and conservation communities have advocated for the future protection of MAFs and their integration into spatial plans and, in response, there are plans to include the characteristics of MAFs into national policies and international directives and conventions (i.e. IUCN, CBD, OSPAR, HELCOM, Barcelona Convention, European directives, ABJN policies etc.). Some MAF ecosystems are already included in international and national conservation and management initiatives, for instance, shallow water coral reefs (ICRI, ICRAN) or cold-water coral reefs and gardens and sponge aggregations (classified as Vulnerable Marine Ecosystems, VMEs), but not as a group together with other ecosystems with similar ecological roles. Marine Animal Forests can be found in all oceans, from shallow to deep waters. They are composed of megabenthic communities dominated by sessile suspension feeders (such as sponges, corals and bivalves) capable of producing three-dimensional frameworks with structural complexity that provide refuge for other species.MAFs are diverse and often harbour highly endemic communities. Marine animal forests face direct anthropogenic threats and they are not protected in many regions, particularly in deep-sea environments. Even though MAFs have been already described in detail, there are still fundamental knowledge gaps regarding their geographical distribution and functioning. A workshop was dedicated to clarifying the definition of MAFs, characterising their structure and functioning, including delineating the ecosystem services that they provide and the threats upon them. The workshop was organised by Working Group 2 of the EU-COST Action “MAF-WORLD” (hereafter WG2), which is responsible for collating and promoting research on mapping, biogeography and biodiversity of MAFs, to identify and reduce these knowledge gaps. Herein, we report on this workshop and its outputs.
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- 2022
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17. Interconnected marine habitats form a single continental-scale reef system in South America
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Pedro B. M. Carneiro, Antônio R. Ximenes Neto, Bruno Jucá-Queiroz, Carlos E. P. Teixeira, Caroline V. Feitosa, Cristiane X. Barroso, Helena Matthews-Cascon, Jader O. de Morais, João E. P. Freitas, Jones Santander-Neto, Jorge T. de Araújo, Leonardo H. U. Monteiro, Lidriana S. Pinheiro, Marcus D. A. Braga, Ralf T. S. Cordeiro, Sergio Rossi, Sonia Bejarano, Sula Salani, Tatiane M. Garcia, Tito M. C. Lotufo, Tyler B. Smith, Vicente V. Faria, and Marcelo O. Soares
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Medicine ,Science - Abstract
Abstract Large gaps in reef distribution may hinder the dispersal of marine organisms, interrupting processes vital to the maintenance of biodiversity. Here we show the presence and location of extensive reef habitats on the continental shelf between the Amazon Reef System (ARS) and the Eastern Brazilian Reef System (ERS), two reef complexes off eastern South America. Formations located 20–50 m deep include both biogenic and geogenic structures. The presence of diverse reef assemblages suggests the widespread occurrence of rocky substrates below 50 m. These habitats represent an expansion of both the ARS and ERS and the closure of the only remaining large-scale gap (~ 1000 km) among West Atlantic reef environments. This indicates that the SW Atlantic harbors a single, yet heterogeneous, reef system that stretches for about 4000 km, and thus, represents one of the largest semi-continuous tropical marine ecosystems in the world.
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- 2022
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18. Plasticity plays a dominant role in regulating the phenological variations of sugar maple populations in Canada
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Xiali Guo, Valentina Buttò, Vasyl Mohytych, Marcin Klisz, Yann Surget-Groba, Jianguo Huang, Sylvain Delagrange, and Sergio Rossi
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Acer saccharum ,bud burst ,common garden ,climate change ,ecotype ,temperature ,Evolution ,QH359-425 ,Ecology ,QH540-549.5 - Abstract
Global changes affect the growing conditions of terrestrial ecosystems, causing a mismatch between plant phenology and local climates in Northern regions. Due to their long lifespan and irregular regeneration periods, trees cannot respond quickly enough to climate variability through long-term genetic adaptation. In this study, we explored the phenological plasticity and genetic variation among populations of bud burst in sugar maple (Acer saccharum Marsh.) seedlings from 30 Canadian provenances with contrasting climates planted in two common gardens near and at the northern limit of the species’ range. We tested the hypothesis that phenotypic plasticity and genetic variation among populations affect bud phenology. We expect that phenotypic plasticity is more important in regulating bud phenology due to the high variability in short-term weather events characterizing this part of North America. Bud development and leafing occurred in April–May, with complete bud burst lasting between 21 and 29 days. On average, bud swelling differed by 12 days between common gardens. Both factors site (common gardens) and provenance significantly affected bud burst, demonstrating phenological plasticity and genetic variation of sugar maple, respectively. A significant interaction between site and provenance was also found. Overall, the site (11.8–90.3%) contributed more than provenance (0–3.1%) to the variance in timings of bud burst, indicating a dominant role of plasticity in regulating spring phenology. Our study demonstrated the concurring effects of genetic variation and phenological plasticity of sugar maple and revealed the dominant role of the latter factor. The high plasticity observed in sugar maple has a crucial role in the phenological adaptation of maple and the survival of its local populations in a context of changing climate.
- Published
- 2023
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19. Warming-induced increase in carbon uptake is linked to earlier spring phenology in temperate and boreal forests
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Hongshuang Gu, Yuxin Qiao, Zhenxiang Xi, Sergio Rossi, Nicholas G. Smith, Jianquan Liu, and Lei Chen
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Science - Abstract
The mechanisms underlying plant phenological shifts are debated. Here, based on phenological observations and ecosystem flux and climate data, Gu and colleagues provide evidence that warming-enhanced photosynthesis in a growing season contributes to earlier spring phenology in the following year in temperate and boreal forests.
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- 2022
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20. Benthic Colonization on New Materials for Marine Ecosystem Restoration in Porto Cesareo, Italy
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Carolina Bracho-Villavicencio, Helena Matthews-Cascon, Marc García-Durán, Xavier Vélez, Nicola Lago, Laura Busquier, and Sergio Rossi
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material ,marine ,artificial reefs ,artificial structures ,benthic ,colonization ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
Suitable colonization materials are a pursued target in marine restoration programs. Known for making nutrients available while reducing pollutants and the risk of pathogens in terrestrial ecosystems, Biochar and Bioferment materials of organic origin were tested during a two-year experiment. We tested the efficacy of these materials for restoration purposes through experimental concrete tiles treated with Biochar (B) and Bioferment (F) and tiles made of concrete, which were used as controls (Ct) for the colonization of marine organisms in the marine protected area of Porto Cesareo, Southern Italy (20 m depth). Tiles were monitored for photographs from October 2019 to September 2021. Initially, Biochar treatment presented a higher percentage of total benthic cover (81.23 ± 2.76, median ± SE), differing from Bioferment treatment and control tiles (45.65 ± 5.43 and 47.95 ± 3.69, respectively). Significant interaction between treatments and times suggests changes in community structure related to Polychaeta cover increase in Bioferment and control materials from the second monitoring time. Furthermore, the underwater instability of Bioferment on the tiles could explain the similarity with control tiles in marine organisms’ covers. Hence, Biochar is shown to be a material with optimal stability in seawater, demonstrating greater capacity for marine organisms’ colonization in less time compared to the other two materials.
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- 2024
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21. Spatio-temporal trends in the frost regime reveal late frost exposure to white spruce (Picea glauca [Moench] Voss) persists in northeastern America
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Benjamin Marquis, Mebarek Lamara, Alexandre Roy, Sergio Rossi, Yves Bergeron, Julie Godbout, Isabelle Aubin, and Martin Perron
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budbreak ,climate change ,climatic extremes ,late frost ,false spring ,picea glauca ,Meteorology. Climatology ,QC851-999 ,Environmental sciences ,GE1-350 - Abstract
The characteristics of the frost regime (intensity, frequency, and timing) contribute to shaping tree species adaptations and distribution as well as ecosystem productivity and functions. However, climate change increases the variability in extreme events; therefore, the different characteristics of the frost regime may diverge under climate change. Using the BioSim 11 software, we simulated daily air temperature at 512 locations over northeastern North America between 1901–2021 to determine how the spatio-temporal trends in the frost regime varied over this complex landscape and if spatio-temporal trends in extreme climatic events such as frosts are stronger compared to changes in aggregated climate variables such as mean annual air temperature and growing degree-days. We also used an eco-physiological model to conduct a case study focussing on white spruce to determine if trees are currently more exposed to growing season frosts than they were in the past by modelling the timings of budburst using the thermal time model. Our results showed that, at 67% of locations (343 locations), the day of the year of the last frost in spring (minimum daily air temperature
- Published
- 2024
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22. Variability in frost occurrence under climate change and consequent risk of damage to trees of western Quebec, Canada
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Benjamin Marquis, Yves Bergeron, Daniel Houle, Martin Leduc, and Sergio Rossi
- Subjects
Medicine ,Science - Abstract
Abstract Climate change affects timings, frequency, and intensity of frost events in northern ecosystems. However, our understanding of the impacts that frost will have on growth and survival of plants is still limited. When projecting the occurrence of frost, the internal variability and the different underlying physical formulations are two major sources of uncertainty of climate models. We use 50 climate simulations produced by a single-initial large climate ensemble and five climate simulations produced by different pairs of global and regional climate models based on the concentration pathway (RCP 8.5) over a latitudinal transect covering the temperate and boreal ecosystems of western Quebec, Canada, during 1955–2099 to provide a first-order estimate of the relative importance of these two sources of uncertainty on the occurrence of frost, i.e. when air temperature is
- Published
- 2022
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23. Detection of Management Practices and Cropping Phases in Wild Lowbush Blueberry Fields Using Multispectral UAV Data
- Author
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Charles Marty, Siddhartha Khare, Sergio Rossi, Jean Lafond, Maxime Boivin, and Maxime C. Paré
- Subjects
Environmental sciences ,GE1-350 ,Technology - Abstract
Normalized difference vegetation index (NDVI) and normalized difference red-edge index (NDRE) are vegetation indices commonly used in agriculture to provide information on crop’s growth and health. Here, we investigated the sensitivity of both indices to management practices in lowbush blueberry fields. Images of the experimental plots were collected with a multispectral camera installed on an unmanned aerial vehicle. Both NDVI and NDRE values were significantly higher in fertilized plots than in controls (0.88 ± 0.03 vs. 0.79 ± 0.03 for NDVI, and 0.37 ± 0.01 vs. 0.33 ± 0.01 for NDRE) due to fertilization effect on vegetative growth. The increase was higher under mineral than organic fertilization during the two first phases of the cropping system (by ∼0.3 and ∼0.2 for NDVI and NDRE, respectively). NDRE was not affected by thermal pruning and fungicide application but was negatively correlated with Septoria infection level. NDVI was more strongly correlated with stem length than NDRE, but unlike NDRE, NDVI was not impacted by the development of reproductive shoots during the harvest phases. Overall, the results indicate that although both index values are correlated, their sensitivity to changes in canopy characteristics differs depending on the cropping phase. Further research must be conducted to relate these indices to blueberry’s nutrient status.
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- 2022
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24. Wildfire promotes the invasion of Robinia pseudoacacia in the unmanaged Mediterranean Castanea sativa coppice forests
- Author
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Luigi Saulino, Angelo Rita, Adriano Stinca, Greta Liuzzi, Roberto Silvestro, Sergio Rossi, and Antonio Saracino
- Subjects
chestnut coppice ,invasive plant traits ,vegetative regeneration ,spring leaf phenology ,remote sensing ,root suckers ,Forestry ,SD1-669.5 ,Environmental sciences ,GE1-350 - Abstract
In the Mediterranean region of southern Europe, Castanea sativa Mill. (Castanea) coppice stands are being invaded by non-native pioneer tree species due to recurrent coppicing and wildfire disturbances. There is a need to control the spread of non-native tree species in Castanea coppices due to their pivotal socio-economic role, however, to facilitate this, further research into invasive strategies and their interactions with disturbances is required. The non-native Robinia pseudoacacia L. (Robinia) has widely colonized the overaged and unmanaged Castanea coppice forests in Vesuvius National Park, which were disturbed by the low-severity fires in the summer of 2017. Here, we aimed to assess the functional traits conferring a competitive advantage to the Robinia over Castanea and the changes in spatial stand patterns driven by wildfire disturbance. To achieve this we assessed the spatial stem patterns, regeneration strategies, and conducted field-assessments and remote sensing of the spring leaf phenology of both Castanea and Robinia in five 300–600 m2 plots. After the 2017 wildfire, root suckers constituted 72% (±12) of the Robinia vegetative living sprouts and occurred up to a distance of 10 m from the adult parent trees under the canopy of the Castanea trees. NDVI-based estimates at the start of the growing season (sos) in Castanea occurred over a 7 day period, from DOY 118–124, increasing at a rate (rsp) of 0.10–0.16, in agreement with the field-based assessment of spring leaf phenology. In Robinia, the sos estimated at DOY 109 from the NDVI seasonal trajectory disagreed with the field-based observations, which started later than Castanea, after approximately DOY 133. Here, the high percentage cover (∼90%) of the understory species influenced NDVI-based estimates of Robinia leaf spring phenology. The results suggest that low-severity wildfires increased the invasiveness of Robinia, and that vegetative regeneration strategies, rather than earlier spring phenology, conferred a competitive advantage in the fire-disturbed Castanea coppice stands. The results thus suggest that appropriate management of invasive Robinia trees to conserve the continuous canopy cover of Castanea stands should guide nature-based solutions to control the spread of non-native tree species.
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- 2023
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25. Heatwaves and a decrease in turbidity drive coral bleaching in Atlantic marginal equatorial reefs
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Caroline Costa Lucas, Carlos Eduardo Peres Teixeira, Marcus Davis Andrade Braga, Francisco Carlos Júnior, Sandra Vieira Paiva, Anne Larisse Gurgel, Sergio Rossi, and Marcelo Oliveira Soares
- Subjects
coral bleaching ,turbidity ,coral reef ,marine heatwave ,marginal reef ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Tropical reefs can occur naturally under suboptimal environmental conditions, where few reef-building corals thrive. These unique reefs are especially important for understanding resistance to global warming, but they are understudied. We studied a coral bleaching event that occurred in turbid reefs (~ 19 m deep) in the equatorial southwestern Atlantic. Mass bleaching was observed in 91% of the Siderastrea stellata colonies in 2020, whereas only 7.7% of the colonies were bleached in 2019 and 10.9% in 2022. The year 2020 had the highest heat stress recorded in this century in this region according to the degree of heating weeks such as 17.6°C-week. In the first semester of 2020, the region also underwent three marine heatwaves (MHWs) above the average temperatures (1.3, 1.5, and 2.0°C). The lowest turbidity and wind speed matched long-lasting, repeated, and severe MHWs. These reef-building corals are dominant under moderate turbid waters and high sea temperature (26–29°C), however they are near the maximum tolerance limit. In this regard, these low-latitude reefs are warming twice as fast (0.2°C/decade) as other regions (e.g., Abrolhos and Coral Coast) (0.1 to 0.13°C/decade) in the South America reef system demonstrating that they cannot be considered climate-change refugia. These results suggest that even turbid marginal reefs and tolerant corals are highly susceptible to mass bleaching, especially when heatwaves and a decrease in turbidity occur simultaneously.
- Published
- 2023
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26. Reproductive cycle and gonadal output of the Lessepsian jellyfish Cassiopea andromeda in NW Sicily (Central Mediterranean Sea).
- Author
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Marta Mammone, Mar Bosch-Belmar, Giacomo Milisenda, Luca Castriota, Mauro Sinopoli, Alessandro Allegra, Manuela Falautano, Teresa Maggio, Sergio Rossi, and Stefano Piraino
- Subjects
Medicine ,Science - Abstract
Knowledge of the reproductive strategy is a key prerequisite to predict population dynamics and potential invasiveness of both native and non-indigenous outbreak-forming species. In 2014 the Lessepsian upside-down jellyfish Cassiopea andromeda reached the harbor of Palermo (NW Sicily, Thyrrenian Sea), to date its established westernmost outpost in the Mediterranean Sea. To predict C. andromeda reproductive success in its novel habitat, gonad histology was carried out to record the number and size of mature and immature oocytes. Both male and female simultaneously presented gametes at all stages of development suggesting an asynchronous, yet apparently continuous, reproduction strategy. Indeed, oogenesis was observed throughout the year from pre-vitellogenic, vitellogenetic, and late-vitellogenetic to mature oocytes suggesting multiple reproductive events, as known in other Mediterranean Rhizostomeae. Oocytes were found from May to December, with two seasonal peaks of abundance (late spring = 392 and autumn = 272), suggesting imminent spawning events. Further, jellyfish size varied significantly throughout the year, with maximum diameter (up to 24 cm) in summer, and minimum diameter (6 cm) in winter. Small-sized jellyfish in winter belong to the new cohort, most probably arising from intense summer strobilation of polyps. Late spring fertilization, planula development, and metamorphosis, followed by polyp strobilation in the summer months, may explain the late appearance of a new jellyfish cohort, likely coincident with that recorded throughout winter.
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- 2023
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27. Editorial: Quantitative wood anatomy to explore tree responses to global change
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Fabio Gennaretti, Marco Carrer, Ignacio García-González, Sergio Rossi, and Georg von Arx
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quantitative wood anatomy (QWA) ,intra-annual resolution ,tree functioning ,trait plasticity ,marginal populations ,climate and environmental reconstructions ,Plant culture ,SB1-1110 - Published
- 2022
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28. Topography modulates near-ground microclimate in the Mediterranean Fagus sylvatica treeline
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Angelo Rita, Giuliano Bonanomi, Emilia Allevato, Marco Borghetti, Gaspare Cesarano, Valentina Mogavero, Sergio Rossi, Luigi Saulino, Maurizio Zotti, and Antonio Saracino
- Subjects
Medicine ,Science - Abstract
Abstract Understanding processes controlling forest dynamics has become particularly important in the context of ongoing climate change, which is altering the ecological fitness and resilience of species worldwide. However, whether forest communities would be threatened by projected macroclimate change or unaffected due to the controlling effect of local site conditions is still a matter for debate. After all, forest canopy buffer climate extremes and promote microclimatic conditions, which matters for functional plant response, and act as refugia for understory species in a changing climate. Yet precisely how microclimatic conditions change in response to climate warming will depend on the extent to which vegetation structure and local topography shape air and soil temperature. In this study, we posited that forest microclimatic buffering is sensitive to local topographic conditions and canopy cover, and using meteorological stations equipped with data-loggers we measured this effect during 1 year across a climate gradient (considering aspect as a surrogate of local topography) in a Mediterranean beech treeline growing in contrasting aspects in southern Italy. During the growing season, the below-canopy near-ground temperatures were, on average, 2.4 and 1.0 °C cooler than open-field temperatures for south and north-west aspects, respectively. Overall, the temperature offset became more negative (that is, lower under-canopy temperatures at the treeline) as the open-field temperature increased, and more positive (that is, higher under-canopy temperatures at the treeline) as the open-field temperature decreased. The buffering effect was particularly evident for the treeline on the south-facing slope, where cooling of near-ground temperature was as high as 8.6 °C for the maximum temperature (in August the offset peaked at 10 °C) and as high as 2.5 °C for the average temperature. In addition, compared to the south-facing slope, the northern site exhibited less decoupling from free-air environment conditions and low variability in microclimate trends that closely track the free-air biophysical environment. Although such a decoupling effect cannot wholly isolate forest climatic conditions from macroclimate regional variability in the south-facing treeline, it has the potential to partly offset the regional macroclimatic warming experienced in the forest understory due to anthropogenic climate change.
- Published
- 2021
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29. Calibrating PhenoCam Data with Phenological Observations of a Black Spruce Stand
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Shaokang Zhang, Valentina Buttò, Siddhartha Khare, Annie Deslauriers, Hubert Morin, Jian-Guo Huang, Hai Ren, and Sergio Rossi
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Environmental sciences ,GE1-350 ,Technology - Abstract
Bud and leaf development are important phenological events and help in defining the growing period of trees. Canopy greenness derived from PhenoCam has been used to investigate leaf phenology. Questions remain on how much the continuous records of canopy greenness represent bud developmental phases, and how growing period boundaries are related to canopy greenness and bud phenology. In this study, we compared bud phenology of black spruce [Picea mariana (Mill.) B.S.P] during 2015, 2017 and 2018 with the canopy greenness, represented by Green Chromatic Coordinate (GCC), derived from PhenoCam images of a boreal stand in Quebec, Canada. Logit models were applied to estimate the probability of observing sequential phenological phases of bud burst and bud set along with GCC. GCC showed a bell-shaped pattern, with a slow increase in spring, a peak in summer and a gradual decrease in autumn. The start and end of budburst, and bud set, occurred when GCC reached 72% and 92% (spring), and 94% (autumn) of its maximum amplitude, respectively. These GCC values are reliable thresholds indicating the growing period boundaries. Our study builds a bridge between phenological observations and automatic near-surface remote sensing, providing a statistically sound protocol for calibrating PhenoCam with field observations.
- Published
- 2020
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30. Editorial: Coral Reef Restoration in a Changing World: Science-Based Solutions
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Jesús E. Arias-González, Iliana B. Baums, Anastazia T. Banaszak, Carlos Prada, Sergio Rossi, Edwin A. Hernández-Delgado, and Baruch Rinkevich
- Subjects
restoration ,climate – change ,resilience ,management ,adaptative evolution ,modeling ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Published
- 2022
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31. Synthesis of Tetrasubstituted Nitroalkenes and Preliminary Studies of Their Enantioselective Organocatalytic Reduction
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Patricia Camarero González, Sergio Rossi, Miguel Sanz, Francesca Vasile, and Maurizio Benaglia
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nitroacrylates ,organocatalysis ,stereoselective synthesis ,reduction ,chiral nitro derivatives ,Organic chemistry ,QD241-441 - Abstract
Starting from commercially available ketones, a reproducible and reliable strategy for the synthesis of tetrasubstituted nitroalkenes was successfully developed, using a two-step procedure; the HWE olefination of the ketone to form the corresponding α,β-unsaturated esters is followed by a nitration reaction to introduce the nitro group in the α position of the ester group. The enantioselective organocatalytic reduction of these compounds has also been preliminarily studied, to access the functionalized enantioenriched nitroalkanes, which are useful starting materials for further synthetic elaborations. The absolute configuration of the reduction product was established by chemical correlation of the chiral nitroalkane with a known product; preliminary DFT calculations were also conducted to rationalize the stereochemical outcome of the organocatalytic enantioselective reduction.
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- 2023
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32. Contrasting Carbon Allocation Strategies of Ring-Porous and Diffuse-Porous Species Converge Toward Similar Growth Responses to Drought
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Valentina Buttó, Mathilde Millan, Sergio Rossi, and Sylvain Delagrange
- Subjects
functional group ,SPEI ,primary growth ,secondary growth ,ramifications ,stem elongation ,Plant culture ,SB1-1110 - Abstract
Extreme climatic events that are expected under global warming expose forest ecosystems to drought stress, which may affect the growth and productivity. We assessed intra-annual growth responses of trees to soil water content in species belonging to different functional groups of tree-ring porosity. We pose the hypothesis that species with contrasting carbon allocation strategies, which emerge from different relationships between wood traits and canopy architecture, display divergent growth responses to drought. We selected two diffuse-porous species (Acer saccharum and Betula alleghaniensis) and two ring-porous species (Quercus rubra and Fraxinus americana) from the mixed forest of Quebec (Canada). We measured anatomical wood traits and canopy architecture in eight individuals per species and assessed tree growth sensitivity to water balance during 2008–2017 using the standardized precipitation evapotranspiration index (SPEI). Stem elongation in diffuse-porous species mainly depended upon the total number of ramifications and hydraulic diameter of the tree-ring vessels. In ring-porous species, stem elongation mainly depended upon the productivity of the current year, i.e., number of vessels and basal area increment. Diffuse-porous and ring-porous species had similar responses to soil water balance. The effect of soil water balance on tree growth changed during the growing season. In April, decreasing soil temperature linked to wet conditions could explain the negative relationship between SPEI and tree growth. In late spring, greater water availability affected carbon partitioning, by promoting the formation of larger xylem vessels in both functional groups. Results suggest that timings and duration of drought events affect meristem growth and carbon allocation in both functional groups. Drought induces the formation of fewer xylem vessels in ring-porous species, and smaller xylem vessels in diffuse-porous species, the latter being also prone to a decline in stem elongation due to a reduced number of ramifications. Indeed, stem elongation of diffuse-porous species is influenced by environmental conditions of the previous year, which determine the total number of ramifications during the current year. Drought responses in different functional groups are thus characterized by different drivers, express contrasting levels of resistance or resilience, but finally result in an overall similar loss of productivity.
- Published
- 2021
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33. Laboratory Scale Continuous Flow Systems for the Enantioselective Phase Transfer Catalytic Synthesis of Quaternary Amino Acids
- Author
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Milena Krstić, Sergio Rossi, Miguel Sanz, and Alessandra Puglisi
- Subjects
continuous flow ,quaternary stereocenter ,phase transfer catalysis (PTC) ,enantioselective synthesis ,packed-bed reactor ,continuous stirred tank reactor ,Organic chemistry ,QD241-441 - Abstract
The use of stereoselective phase-transfer catalysis as a reliable method for the enantioselective synthesis of optically active α-amino acid derivatives using achiral Schiff base esters has been well-developed in batch in the last 40 years. Recently, continuous flow technology has become of great interest in the academy and industry, since it offers safer process operating conditions and higher efficiency compared to a traditional batch processing. Herein, we wish to report the first example of enantioselective phase transfer benzylation of alanine Schiff base ester, under continuous flow conditions. Two different methodologies were investigated: a liquid-solid phase transfer catalytic benzylation using a packed-bed reactor and a liquid-liquid phase transfer catalytic benzylation in continuous stirred-tank reactors. Liquid-liquid phase transfer process in flow showed slightly better productivity than the batch process, while solid-liquid phase transfer benzylation proved much more advantageous in terms of productivity and space-time yield. Furthermore, continuous flow system allowed the isolation of benzylated product without any work up, with a significant simplification of the process. In both cases, phase transfer asymmetric benzylation promoted by Maruoka catalyst demonstrated high enantioselectivity of target quaternary amino ester in flow, up to 93% ee.
- Published
- 2023
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34. Origin of Intra-annual Density Fluctuations in a Semi-arid Area of Northwestern China
- Author
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Jiani Gao, Sergio Rossi, and Bao Yang
- Subjects
water availability ,IADF ,xylogenesis ,cambial activity ,Chinese pine ,cell enlargement ,Plant culture ,SB1-1110 - Abstract
Intra-annual density fluctuation (IADF) is a structural modification of the tree ring in response to fluctuations in the weather. The expected changes in monsoon flow would lead to heterogeneous moisture conditions during the growing season and increase the occurrence of IADF in trees of the arid ecosystems of continental Asia. To reveal the timings and physiological mechanisms behind IADF formation, we monitored cambial activity and wood formation in Chinese pine (Pinus tabuliformis) during 2017–2019 at three sites in semi-arid China. We compared the dynamics of xylem formation under a drought event, testing the hypothesis that drought affects the process of cell enlargement and thus induces the production of IADF. Wood microcores collected weekly from April to October were used for anatomical analyses to estimate the timings of cambial activity, and the phases of enlargement, wall thickening, and lignification of the xylem. The first cells started enlargement from late April to early May. The last latewood cells completed differentiation in mid-September. Trees produced IADF in 2018. During that year, a drought in June limited cell production in the cambium, only 36% of the xylem cells being formed in IADF trees, compared to 68% in normal tree rings. IADF cells enlarged under drought in early July and started wall thickening during the rainfall events of late July. The drought restricted cell enlargement and affected wall thickening, resulting in narrow cells with wide walls. Cambium and cell enlargement recovered from the abundant rainfall, producing a new layer with large earlywood tracheids. IADF is a specific adaptation of trees to cope with water deficit events occurring during xylem formation. Our findings confirmed the hypothesis that the June-July drought induces latewood-like IADFs by limiting the process of cell enlargement in the xylem. Our finding suggests a higher occurrence of IADF in trees of arid and semi-arid climates of continental Asia if the changes to monsoon flows result in more frequent drought events during the earlywood formation in June.
- Published
- 2021
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35. Seasonal trends of the polyp expansion and nutritional condition of Alcyonium acaule (Octocorallia, Alcyonacea)
- Author
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Lucia Rizzo, Ida Fiorillo, and Sergio Rossi
- Subjects
Marine animal forest ,Habitat-forming species ,Anthozoans ,Polyp expansion ,Organic matter ,Octocorals ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
The ecological physiology of anthozoans, as well as their resistance to stressors, are strongly influenced by environmental factors and the availability of resources. The energy budget of anthozoans can vary seasonally in order to find an equilibrium between the available resources and respiration, polyp activity, growth, and reproduction processes. The variation in the biochemical composition of the animal tissues in these organisms results from a combination of the productivity processes of the water column coupled with the reproductive effort and potential starvation periods of the anthozoans. Here, the seasonal variation in the polyp activity of a slow-growing passive suspension feeder, the octocoral Alcyonium acaule, as well as their carbohydrate, protein and lipid contents, was investigated in a warm temperate environment using in-situ observations and biochemical analyses. Polyp activity exhibited a significant variability that was moderately dependent on season, while an aestivation phenomenon in A. acaule (i.e., a resting period in which the anthozoan is not capable of any polyp activity) during the warmer months is clearly observed. Carbohydrate concentrations in the coral species showed a significant increase in the late winter and spring seasons, and the lipid content increased during the spring. A higher abundance of lipids and carbohydrates coincided with a higher primary productivity in the water column, as well as with the octocoral reproduction period. In late autumn, there was a depletion of these biomolecules, with protein levels exhibiting great variability across sampling times. Complex alterations driven by climate change could affect the energy fluxes that depend on the dead or alive particles that are intercepted by marine animal forests. The obtained findings show a food shortage in late summer and autumn of the benthic suspension feeder A. acaule through the integrative descriptors of the ecophysiology of these anthozoans. This research contributes to the knowledge of energy storage capabilities in benthic suspension feeders in general, highlighting the importance of understanding the limits of resistance to starvation periods through these indicators.
- Published
- 2021
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36. Needs and Gaps in Optical Underwater Technologies and Methods for the Investigation of Marine Animal Forest 3D-Structural Complexity
- Author
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Paolo Rossi, Massimo Ponti, Sara Righi, Cristina Castagnetti, Roberto Simonini, Francesco Mancini, Panagiotis Agrafiotis, Leonardo Bassani, Fabio Bruno, Carlo Cerrano, Paolo Cignoni, Massimiliano Corsini, Pierre Drap, Marco Dubbini, Joaquim Garrabou, Andrea Gori, Nuno Gracias, Jean-Baptiste Ledoux, Cristina Linares, Torcuato Pulido Mantas, Fabio Menna, Erica Nocerino, Marco Palma, Gaia Pavoni, Alessandro Ridolfi, Sergio Rossi, Dimitrios Skarlatos, Tali Treibitz, Eva Turicchia, Matan Yuval, and Alessandro Capra
- Subjects
biodiversity ,3D monitoring ,semantic segmentation ,underwater photogrammetry ,biogenic reefs conservation ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Marine animal forests are benthic communities dominated by sessile suspension feeders (such as sponges, corals, and bivalves) able to generate three-dimensional (3D) frameworks with high structural complexity. The biodiversity and functioning of marine animal forests are strictly related to their 3D complexity. The present paper aims at providing new perspectives in underwater optical surveys. Starting from the current gaps in data collection and analysis that critically limit the study and conservation of marine animal forests, we discuss the main technological and methodological needs for the investigation of their 3D structural complexity at different spatial and temporal scales. Despite recent technological advances, it seems that several issues in data acquisition and processing need to be solved, to properly map the different benthic habitats in which marine animal forests are present, their health status and to measure structural complexity. Proper precision and accuracy should be chosen and assured in relation to the biological and ecological processes investigated. Besides, standardized methods and protocols are strictly necessary to meet the FAIR (findability, accessibility, interoperability, and reusability) data principles for the stewardship of habitat mapping and biodiversity, biomass, and growth data.
- Published
- 2021
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37. Supported Eosin Y as a Photocatalyst for C-H Arylation of Furan in Batch and Flow
- Author
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Sergio Rossi, Fabian Herbrik, Simonetta Resta, and Alessandra Puglisi
- Subjects
photocatalysis ,eosin Y ,supported catalysis ,continuous flow photochemistry ,green chemistry ,Organic chemistry ,QD241-441 - Abstract
Eosin Y is one of the most popular organic dyes used as a photoredox catalyst and is largely employed in photochemical reactions both as a homogeneous and heterogeneous photocatalyst after immobilization. Immobilization of Eosin Y onto a solid support has many advantages, such as the possibility of recovery and reuse of the photocatalyst and the possibility of its use under flow conditions. In this paper, we report our findings on the immobilization of Eosin Y onto Merrifield resin and its application in the direct photochemical arylation of furan with aryldiazonium salts. The synthesized supported photocatalyst was used in batch reactions under heterogeneous conditions with different aryl diazonium salts, and its recovery and recycle were demonstrated for up to three times. The immobilized photocatalyst was then loaded in a packed-bed reactor and used under continuous flow conditions. The flow reaction allowed the arylated products to be obtained with higher productivity and space-time-yield than the batch in a very short reaction time.
- Published
- 2022
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38. Author Correction: Warming-induced increase in carbon uptake is linked to earlier spring phenology in temperate and boreal forests
- Author
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Hongshuang Gu, Yuxin Qiao, Zhenxiang Xi, Sergio Rossi, Nicholas G. Smith, Jianquan Liu, and Lei Chen
- Subjects
Science - Published
- 2022
- Full Text
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39. A 15-year spatio-temporal analysis of plant β-diversity using Landsat time series derived Rao’s Q index
- Author
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Siddhartha Khare, Hooman Latifi, and Sergio Rossi
- Subjects
β-diversity ,Rao’s Q index ,Time series ,NDVI ,MSAVI ,Google Earth Engine ,Ecology ,QH540-549.5 - Abstract
Understanding temporal dynamics of plant biodiversity is crucial for conservation strategies at regional and local levels. The mostly applied hitherto methods are based on field observations of the plant communities and the related taxa. Satellite earth observation time series offer continuous and wider coverage for the assessment of plant diversity, especially in remote areas. Theoretical basis and large-scale solutions for assessing beta-diversity have been recently presented. Yet landscape-scale and context-based analysis are missing. We assessed temporal β-diversity using Raós Q diversity derived from Landsat-based vegetation indices by considering the effect of ERA-5 monthly aggregates environmental factors (temperature and precipitation) extracted using Google Earth Engine (GEE), land use classes, and two common vegetation indices. We derived 15-year Rao’s Q diversity using Landsat-7 based normalized difference vegetation index (NDVI) and modified soil-adjusted vegetation index (MSAVI). We evaluated the temporal turnover in Rao’s Q on multiple land use classes, including agriculture, intact forest and areas affected by and invasive species. Vegetation index and Rao’s Q diverged between pre- and post- monsoon seasons. Rao’s Q had higher temporal turnover with NDVI than MSAVI for all vegetation classes, however the latter showed higher sensitivity towards temperature and precipitation. Moreover, agriculture generally showed higher variability than forest and invasive species. The temporal turnover was correlated between NDVI and MSAVI for all vegetation classes, which indicated that the variability among vegetation types was directly related to spectral heterogeneity. Furthermore, MSAVI was less sensitive to the effect of soil in assessing the vegetation indices, which resulted in higher global sensitivity of QMSAVI. Near infrared and red spectra used in vegetation indices are able to capture a small variation in leaf traits reflectance for vegetation types. Here, the β-diversities and their temporal dynamics derived from the vegetation indices differed based on their sensitivity to soil, vegetation density and seasonality. This approach and its open source implementation can be tested for different forest ecosystems at varying spatial scales.
- Published
- 2021
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40. High photosynthetic plasticity may reinforce invasiveness of upside-down zooxanthellate jellyfish in Mediterranean coastal waters.
- Author
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Marta Mammone, Christine Ferrier-Pagés, Silvia Lavorano, Lucia Rizzo, Stefano Piraino, and Sergio Rossi
- Subjects
Medicine ,Science - Abstract
Ecological profiling of non-native species is essential to predict their dispersal and invasiveness potential across different areas of the world. Cassiopea is a monophyletic taxonomic group of scyphozoan mixotrophic jellyfish including C. andromeda, a recent colonizer of sheltered, shallow-water habitats of the Mediterranean Sea, such as harbors and other light-limited, eutrophic coastal habitats. To assess the ecophysiological plasticity of Cassiopea jellyfish and their potential to spread across the Mare Nostrum by secondary introductions, we investigated rapid photosynthetic responses of jellyfish to irradiance transitions-from reduced to increased irradiance conditions (as paradigm of transition from harbors to coastal, meso/oligotrophic habitats). Laboratory incubation experiments were carried out to compare oxygen fluxes and photobiological variables in Cassiopea sp. immature specimens pre-acclimated to low irradiance (PAR = 200 μmol photons m-2 s-1) and specimens rapidly exposed to higher irradiance levels (PAR = 500 μmol photons m-2 s-1). Comparable photosynthetic potential and high photosynthetic rates were measured at both irradiance values, as also shown by the rapid light curves. No significant differences were observed in terms of symbiont abundance between control and treated specimens. However, jellyfish kept at the low irradiance showed a higher content in chlorophyll a and c (0.76±0.51SD vs 0.46±0.13SD mg g-1 AFDW) and a higher Ci (amount of chlorophyll per cell) compared to jellyfish exposed to higher irradiance levels. The ratio between gross photosynthesis and respiration (P:R) was >1, indicating a significant input from the autotrophic metabolism. Cassiopea sp. specimens showed high photosynthetic performances, at both low and high irradiance, demonstrating high potential to adapt to sudden changes in light exposure. Such photosynthetic plasticity, combined with Cassiopea eurythermal tolerance and mixotrophic behavior, jointly suggest the upside-down jellyfish as a potentially successful invader in the scenario of a warming Mediterranean Sea.
- Published
- 2021
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41. Comparing the Cell Dynamics of Tree-Ring Formation Observed in Microcores and as Predicted by the Vaganov–Shashkin Model
- Author
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Valentina Buttò, Vladimir Shishov, Ivan Tychkov, Margarita Popkova, Minhui He, Sergio Rossi, Annie Deslauriers, and Hubert Morin
- Subjects
modeling ,xylogenesis ,cell diameter ,timings ,cambial cells ,black spruce ,Plant culture ,SB1-1110 - Abstract
New insights into the intra-annual dynamics of tree-ring formation can improve our understanding of tree-growth response to environmental conditions at high-resolution time scales. Obtaining this information requires, however, a weekly monitoring of wood formation, sampling that is extremely time-intensive and scarcely feasible over vast areas. Estimating the timing of cambial and xylem differentiation by modeling thus represents an interesting alternative for obtaining this important information by other means. Temporal dynamics of cambial divisions can be extracted from the daily tree-ring growth rate computed by the Vaganov–Shashkin (VS) simulation model, assuming that cell production is tightly linked to tree-ring growth. Nonetheless, these predictions have yet to be compared with direct observations of wood development, i.e., via microcoring, over a long time span. We tested the performance of the VS model by comparing the observed and predicted timing of wood formation in black spruce [Picea mariana (Mill.)]. We obtained microcores over 15 years at 5 sites along a latitudinal gradient in Quebec (Canada). The measured variables included cell size and the timing of cell production and differentiation. We calibrated the VS model using daily temperature and precipitation recorded by weather stations located on each site. The predicted and observed timing of cambial and enlarging cells were highly correlated (R2 = 0.8); nonetheless, we detected a systematic overestimation in the predicted timing of cambial cells, with predictions delayed by 1–20 days compared with observations. The growth rate of cell diameter was correlated with the predicted growth rate assigned to each cambial cell, confirming that cell diameter developmental dynamics have the potential to be inferred by the tree-ring growth curve of the VS model. Model performances decrease substantially in estimating the end of wood formation. The systematic errors suggest that the actual relationships implemented in the model are unable to explain the phenological events in autumn. The mismatch between the observed and predicted timing of wood formation in black spruce within our study area can be reduced by better adapting the VS model to wet sites, a context for which this model has been rarely used.
- Published
- 2020
- Full Text
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42. El estado de la macroeconomía
- Author
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Louis-Philippe Rochon and Sergio Rossi
- Subjects
Macroeconomía ,l a Gran Mode ración ,el Nuevo Consenso en Economía ,Equilibrio General Estocástico Dinámico ,Macroeconomics ,the Great Moderation ,the New Consensus in Economics ,Dynamic Stochastic General Equilibrium ,Economic growth, development, planning ,HD72-88 ,Economics as a science ,HB71-74 - Abstract
Este ensayo examina de cerca esta llamada "guerra civil", y si conlleva a alguna consecuencia para el desarrollo futuro de la macroeconomía, o si es solo una tormenta de microfundamentos en una tetera. Al hacerlo, se argumenta que si bien la crítica disidente es ciertamente bienvenida desde una perspectiva poskeynesiana, no equivale al rechazo del pensamiento o modelos actuales, sino a algunos ajustes alrededor de los bordes.
- Published
- 2018
43. Seasonal Dietary Shifts of the Gammarid Amphipod Gondogeneia antarctica in a Rapidly Warming Fjord of the West Antarctic Peninsula
- Author
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In-Young Ahn, Francyne Elias-Piera, Sun-Yong Ha, Sergio Rossi, and Dong-U Kim
- Subjects
Gondogeneia antarctica ,seasonal dietary shift ,macroalgae ,benthic diatoms ,C and N stable isotopes ,West Antarctic Peninsula ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
The amphipod Gondogeneia antarctica is among the most abundant benthic organisms, and a key food web species along the rapidly warming West Antarctic Peninsula (WAP). However, little is known about its trophic strategy for dealing with the extreme seasonality of Antarctic marine primary production. This study, using trophic markers, for the first time investigated seasonal dietary shifts of G. antarctica in a WAP fjord. We analyzed δ13C and δ15N in G. antarctica and its potential food sources. The isotopic signatures revealed a substantial contribution of red algae to the amphipod diet and also indicated a significant contribution of benthic diatoms. The isotope results were further supported by fatty acid (FA) analysis, which showed high similarities in FA composition (64% spring–summer, 58% fall–winter) between G. antarctica and the red algal species. G. antarctica δ13C showed a small shift seasonally (−18.9 to −21.4‰), suggesting that the main diets do not change much year-round. However, the relatively high δ15N values as for primary consumers indicated additional dietary sources such as animal parts. Interestingly, G. antarctica and its potential food sources were significantly enriched with δ15N during the fall–winter season, presumably through a degradation process, suggesting that G. antarctica consumes a substantial portion of its diets in the form of detritus. Overall, the results revealed that G. antarctica relies primarily on food sources derived from benthic primary producers throughout much of the year. Thus, G. antarctica is unlikely very affected by seasonal Antarctic primary production, and this strategy seems to have allowed them to adapt to shallow Antarctic nearshore waters.
- Published
- 2021
- Full Text
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44. Comparing Time-Lapse PhenoCams with Satellite Observations across the Boreal Forest of Quebec, Canada
- Author
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Siddhartha Khare, Annie Deslauriers, Hubert Morin, Hooman Latifi, and Sergio Rossi
- Subjects
PhenoCam ,GCC ,NDVI ,EVI ,Google Earth Engine ,Picea mariana ,Science - Abstract
Intercomparison of satellite-derived vegetation phenology is scarce in remote locations because of the limited coverage area and low temporal resolution of field observations. By their reliable near-ground observations and high-frequency data collection, PhenoCams can be a robust tool for intercomparison of land surface phenology derived from satellites. This study aims to investigate the transition dates of black spruce (Picea mariana (Mill.) B.S.P.) phenology by comparing fortnightly the MODIS normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI) extracted using the Google Earth Engine (GEE) platform with the daily PhenoCam-based green chromatic coordinate (GCC) index. Data were collected from 2016 to 2019 by PhenoCams installed in six mature stands along a latitudinal gradient of the boreal forests of Quebec, Canada. All time series were fitted by double-logistic functions, and the estimated parameters were compared between NDVI, EVI, and GCC. The onset of GCC occurred in the second week of May, whereas the ending of GCC occurred in the last week of September. We demonstrated that GCC was more correlated with EVI (R2 from 0.66 to 0.85) than NDVI (R2 from 0.52 to 0.68). In addition, the onset and ending of phenology were shown to differ by 3.5 and 5.4 days between EVI and GCC, respectively. Larger differences were detected between NDVI and GCC, 17.05 and 26.89 days for the onset and ending, respectively. EVI showed better estimations of the phenological dates than NDVI. This better performance is explained by the higher spectral sensitivity of EVI for multiple canopy leaf layers due to the presence of an additional blue band and an optimized soil factor value. Our study demonstrates that the phenological observations derived from PhenoCam are comparable with the EVI index. We conclude that EVI is more suitable than NDVI to assess phenology in evergreen species of the northern boreal region, where PhenoCam data are not available. The EVI index could be used as a reliable proxy of GCC for monitoring evergreen species phenology in areas with reduced access, or where repeated data collection from remote areas are logistically difficult due to the extreme weather.
- Published
- 2021
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45. Electrochemical Organic Synthesis of Electron-Rich Biaryl Scaffolds: An Update
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Fabrizio Medici, Simonetta Resta, Alessandra Puglisi, Sergio Rossi, Laura Raimondi, and Maurizio Benaglia
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biaryls ,electrorganic synthesis ,aryls coupling ,electrodes ,radical chemistry ,Organic chemistry ,QD241-441 - Abstract
Biaryl scaffolds are widely spread in biologically important natural products, in numerous therapeutic agents, but they are also considered a privileged class of ligands and (organo)catalysts; therefore, the development of efficient alternative methodologies to prepare such compounds is always attracting much attention. The present review discusses the organic electrosynthesis of biaryls starting from phenols, anilines, naphthols, and naphthylamines. The most significant examples of the works reported in the last decade are presented and classified according to the single class of molecules: after the introduction, the first three sections relate to the reactions of phenols, naphthols, and anilines, respectively; the other two sections refer to cross-coupling and miscellaneous reactions.
- Published
- 2021
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46. Serviços econssistêmicos costeiros e comunidades tradicionais
- Author
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Luciana de Souza Queiroz, Antônio Jeovah de Andrade Meireles, and Sergio Rossi Heras
- Subjects
Geography (General) ,G1-922 - Abstract
Nas últimas décadas, a despeito de sua importância socioambiental, cultural e econômica, muitos ecossistemas costeiros têm alcançado altos níveis de deterioro. Uma degradação causada principalmente pelo desenvolvimento de atividades industriais, a exemplo do cultivo de camarão em cativeiro (principal ameaça aos manguezais) e da produção de energia eólica (ameaça aos sistemas dunares), que reduzem o fluxo de serviços ecossistêmicos (SE) prestados pela natureza à sociedade. Isto se deve ao fato de que durante a definição das políticas de gestão costeira, desde um ponto de vista de sistema complexo, multidimensional e vinculados ao modo de vida das comunidades tradicionais, são desconsiderados frente às potenciais vantagens econômicas das atividades industriais. Este artigo lança luz sobre a vinculação entre os serviços ecossistêmicos e o bem-estar das comunidades tradicionais e faz uma reflexão sobre os critérios indispensáveis que devem ser considerados para o avanço da gestão dos ecossistemas.
- Published
- 2017
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47. Set-Up of Bacterial Cellulose Production From the Genus Komagataeibacter and Its Use in a Gluten-Free Bakery Product as a Case Study
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Ileana Vigentini, Vincenzo Fabrizio, Federico Dellacà, Sergio Rossi, Isabella Azario, Cristiano Mondin, Maurizio Benaglia, and Roberto Foschino
- Subjects
bacterial cellulose ,Komagataeibacter (Gluconacetobacter) ,Komagataeibacter rhaeticus ,gluten-free products ,bread additives ,Microbiology ,QR1-502 - Abstract
The use of bacterial cellulose (BC) in food systems is still limited due to production costs. Nine clones belonging to Komagataeibacter hansenii, Komagataeibacter nataicola, Komagataeibacter rhaeticus, Komagataeibacter swingsii, and Komagataeibacter xylinus species were screened for cellulose productivity in growth tests with five different carbon sources and three nitrogen sources. The water-holding and rehydration capacities of the purified cellulose were determined. The structure of the polymer was investigated through nuclear magnetic resonance (NMR) spectroscopy, attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy and X-ray diffraction (XRD) analysis, and observed by scanning electron microscope (SEM). Natural mutants of K. rhaeticus LMG 22126T and K. swingsii LMG 22125T showed different productivity. The factors “bacterial isolate” and “nitrogen source” significantly affected the production of cellulose (p < 0.01) rather than the factor “carbon source” (p = 0.15). However, on average, the best conditions for increasing yield were found in medium containing glucose and peptone. Water-holding capacity (WHC) values ranged from 10.7 to 42.3 (gwater/gcellulose) with significant differences among strains (p < 0.01), while the rehydration capacity varied from 4.2 to 9.3 (gwater/gcellulose). A high crystallinity (64–80%) was detected in all samples with Iα fractions corresponding to 67–93%. The ATR-FT-IR spectra and the XRD patterns confirmed the expected structure. BC made by GVP isolate of K. rhaeticus LMG 22126T, which was the strain with the highest yield, was added to a gluten-free bread formulation. Results obtained from measurements of technological parameters in dough leavening and baking trials were promising for implementation in potential novel foods.
- Published
- 2019
- Full Text
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48. Polyp expansion of passive suspension feeders: a red coral case study
- Author
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Sergio Rossi, Lucia Rizzo, and Jean-Claude Duchêne
- Subjects
Octocorals ,Passive suspension feeders ,Optimal foraging theory ,Corallium rubrum ,Activity rhythms ,Trophic ecology ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Polyp activity in passive suspension feeders has been considered to be affected by several environmental factors such as hydrodynamics, water temperature and food concentration. To better elucidate the driving forces controlling polyp expansion in these organisms and the potential role of particle concentration, the octocoral Corallium rubrum was investigated in accordance with two approaches: (1) high-frequency in-situ observations examining various environmental and biological variables affecting the water column, and (2) video-recorded flume-controlled laboratory experiments performed under a range of environmental and biological conditions, in terms of water temperature, flow speed, chemical signals and zooplankton. In the field, C. rubrum polyp expansion correlated positively with particle (seston and zooplankton) concentration and current speed. This observation was confirmed by the flume video records of the laboratory experiments, which showed differences in polyp activity due to changes in temperature and current speed, but especially in response to increasing nutritional stimuli. The maximum activity was observed at the highest level of nutritional stimulus consisting of zooplankton. Zooplankton and water movement appeared to be the main factors controlling polyp expansion. These results suggest that the energy budget of passive suspension feeders (and probably the benthic community as a whole) may rely on their ability to maximise prey capture during food pulses. The latter, which may be described as discontinuous organic matter (dead or alive) input, may be the key to a better understanding of benthic-pelagic coupling processes and trophic impacts on animal forests composed of sessile suspension feeders.
- Published
- 2019
- Full Text
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49. Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane
- Author
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Riccardo Porta, Alessandra Puglisi, Giacomo Colombo, Sergio Rossi, and Maurizio Benaglia
- Subjects
chemoselectivity ,continuous processes ,flow synthesis ,nitro reduction ,trichlorosilane ,Science ,Organic chemistry ,QD241-441 - Abstract
The metal-free reduction of nitro compounds to amines mediated by trichlorosilane was successfully performed for the first time under continuous-flow conditions. Aromatic as well as aliphatic nitro derivatives were converted to the corresponding primary amines in high yields and very short reaction times with no need for purification. The methodology was also extended to the synthesis of two synthetically relevant intermediates (precursors of baclofen and boscalid).
- Published
- 2016
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50. Towards the development of continuous, organocatalytic, and stereoselective reactions in deep eutectic solvents
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Davide Brenna, Elisabetta Massolo, Alessandra Puglisi, Sergio Rossi, Giuseppe Celentano, Maurizio Benaglia, and Vito Capriati
- Subjects
continuous process ,DES ,organocatalysis ,proline ,stereoselective aldol reaction ,Science ,Organic chemistry ,QD241-441 - Abstract
Different deep eutectic solvent (DES) mixtures were studied as reaction media for the continuous synthesis of enantiomerically enriched products by testing different experimental set-ups. L-Proline-catalysed cross-aldol reactions were efficiently performed in continuo, with high yield (99%), anti-stereoselectivity, and enantioselectivity (up to 97% ee). Moreover, using two different DES mixtures, the diastereoselectivity of the process could be tuned, thereby leading to the formation, under different experimental conditions, to both the syn- and the anti-isomer with very high enantioselectivity. The excess of cyclohexanone was recovered and reused, and the reaction could be run and the product isolated without the use of any organic solvent by a proper choice of DES components. The dramatic influence of the reaction media on the reaction rate and stereoselectivity of the process suggests that the intimate architecture of DESs deeply influences the reactivity of different species involved in the catalytic cycle.
- Published
- 2016
- Full Text
- View/download PDF
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