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Through the analysis of benthic foraminifera in the soft bottom sediments of the Laizhou Bay – Yellow River Delta system, this study characterized the foraminiferal biotopes and explored the possibility of obtaining an index of ecological quality comparable with other estuarine and coastal environments of the world. Five foraminiferal biotopes have been identified and their distribution patterns highlight the ecological stress from the marine-fluvial water mixing and pollution. The foraminiferal species were analyzed as a function of organic carbon gradients, and the main species were assigned to four ecological groups based on their sensitivity/tolerance towards an increasing stress gradient. Finally, the relative proportions of the species assigned to the four different ecological groups were used for the definition of a marine biotic index based on foraminifera, i.e. the Foram-AMBI, and thus the assessment of the ecological quality status of marine soft-bottom habitats.

Here we present a rapid and versatile method for capturing and concentrating SARS-CoV-2 from contrived transport medium and saliva samples using affinity-capture magnetic hydrogel particles. We demonstrate that the method concentrates virus from 1 mL samples prior to RNA extraction, substantially improving detection of virus using real-time RT-PCR across a range of viral titers (100–1,000,000 viral copies/mL) and enabling detection of virus using the 2019 nCoV CDC EUA Kit down to 100 viral copies/mL. This method is compatible with commercially available nucleic acid extraction kits (i.e., from Qiagen) and a simple heat and detergent method that extracts viral RNA directly off the particle, allowing a sample processing time of 10 min. We furthermore tested our method in transport medium diagnostic remnant samples that previously had been tested for SARS-CoV-2, showing that our method not only correctly identified all positive samples but also substantially improved detection of the virus in low viral load samples. The average improvement in cycle threshold value across all viral titers tested was 3.1. Finally, we illustrate that our method could potentially be used to enable pooled testing, as we observed considerable improvement in the detection of SARS-CoV-2 RNA from sample volumes of up to 10 mL. Published version

[Departement_IRSTEA]Territoires [TR1_IRSTEA]SEDYVIN [ADD1_IRSTEA]Adaptation des territoires au changement global; International audience; In the French Mediterranean, large fires have significant socio-economic and environmental impacts. The previous works dealing with fires in the French Mediterranean were based on gridded fire data commencing from the mid-1970s (e.g., Ruffault et al., 2016; Fréjaville and Curt, 2017; Ganteaume and Guerra, 2018; Lahaye et al., 2018). Working with longer time-series of georeferenced fires (extending back to 1958) would allow examining both spatial and temporal distributions of large fires (>100 ha) across the French Mediterranean. The objectives of this work were (i) to identify the locations associated with large fire recurrence and to quantify the spatial extent of the region with reburns, (ii) to establish the mean fire extent and the fire return level as well as the LF causes along a longitudinal transect spanning the study area (identifying possible roles of climate conditions and fuel continuity in shaping this longitudinal gradient), and (iii), building on previous research, to re-estimate trends in large fires across the region taking advantage of a fire record spanning almost six decades. A long-term geo-referenced fire time series (1958-2017) was used to analyse both spatial and temporal distributions of large fires (LF; ≥100 ha). Large fire causes were analysed according to the regional fire database Promethée that has recorded fires since 1973. The region was impacted in some locations up to 6 times by recurrent LF (Fig. 1) and 21% of the total area burned by LF occurred on a surface that previously burned in the past, with potential impact on forest resilience. We found contrasting patterns between the East and the West of the study area, the former experiencing fewer LF but of a larger extent compared to the latter, with an average time of occurrence between LF exceeding 4,000 ha 50 years in the West. This longitudinal gradient in LF return level contrasts with what we would expect from mean fire weather conditions strongly decreasing eastwards during the fire season but is consistent with larger fuel cover in the East, highlighting the strong role of fuel continuity in fire spread (Fig. 2). Figure 1: Fire recurrence on the 1961-2017 and 1958-2016 period in the western and eastern areas, respectively. Figure 2: Top) Longitudinal cross-section of mean LF extent computed over 30-km sliding windows. The 95% confidence intervals were estimated using a bootstrapping approach. Bottom) Same as top panel but for mean June-September FWI (in red) and the percent of biomass (in green). Additionally, our analysis confirms the sharp decrease in both LF frequency and burned area in the early 1990s, due to the efficiency of fire suppression and prevention reinforced at that time, thereby weakening the functional climate-fire relationship across the region. Regarding the causes of LF, the proportion of unknown cause was high throughout the region, varying from 74% to 77% from the West to the East. It is worth noting that the knowledge of smaller fires

International audience; Large wildfires across parts of France can cause devastating damage which puts lives, infrastructure, and the natural ecosystem at risk. In the climate change context, it is essential to better understand how these large wildfires relate to weather and climate and how they might change in a warmer world. Such projections rely on the development of a robust modelling framework linking large wildfires to present-day atmospheric variability. Drawing from a MODIS product and a gridded meteorological dataset, we derived a suite of biophysical and fire danger indices and developed generalized linear models simulating the probability of large wildfires ( > 100 ha) at 8 km spatial and daily temporal resolutions across the entire country over the last two decades. The models were able to reproduce large-wildfire activity across a range of spatial and temporal scales. Different sensitivities to weather and climate were detected across different environmental regions. Long-term drought was found to be a significant predictor of large wildfires in flammability-limited systems such as the Alpine and south-western regions. In the Mediterranean, large wildfires were found to be associated with both short-term fire weather conditions and longer-term soil moisture deficits, collectively facilitating the occurrence of large wildfires. Simulated probabilities on days with large wildfires were on average 2-3 times higher than normal with respect to the mean seasonal cycle, highlighting the key role of atmospheric variability in wildfire spread. The model has wide applications, including improving our understanding of the drivers of large wildfires over the historical period and providing a basis on which to estimate future changes to large wildfires from climate scenarios.

Made available in DSpace on 2018-12-11T17:16:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 Natural Resources Conservation Service The objective of this study was to determine the effect of stockpiled forage type and protein supplementation on VFA production, serum metabolites, and BW in yearling beef heifers. Over 2 yr, spring-born, Angus crossbred yearling beef heifers (n = 42; 305 ± 2.9 kg initial BW) were randomly assigned to 1 of 3 forage pasture types: 1) endophyteinfected tall fescue [TF; Schedonorus arundinaceus (Schreb.) Dumort], 2) a big bluestem (Andropogon gerardii Vitman) and indiangrass (Sorghastrum nutans L.) combination (BI), or 3) switchgrass (SG; Panicum virgatum L.). Each pasture was then randomly assigned to receive either 1 of 2 isonitrogenous CP treatments: 1) 0.68 kg·heifer−1·d−1 of dried distiller’s grains with solubles (DDGS; 28% CP and 88% TDN) or 2) 0.22 kg·heifer−1·d−1 of blood meal and fish meal (BF; 72.5% CP and 69.5% TDN), resulting in a 3 × 2 factorial arrangement of treatments. Treatments were initiated in January and terminated in April in both years of the study. Body weights and blood samples were collected approximately every 28 d from initiation of grazing until the end of the trial. Heifer BW change from January to February and overall BW change were greater (P < 0.01) for TF heifers. However, BW change from March to April was not different (P = 0.84) among forage types. Supplement type did not influence (P ≥ 0.13) BW or BW change from January to February and from January to April; however, heifers fed DDGS had greater (P = 0.03) BW gain from March to April. Heifer BW change from February to March exhibited (P < 0.05) a forage type × supplement interaction, with BF-fed heifers gaining more BW on BI pastures than DDGSfed heifers. Serum glucose concentrations, ruminal acetate, and the acetate:propionate ratio were greater (P ≤ 0.04) for SG heifers. However, circulating serum NEFA and urea N (SUN) concentrations were not different (P ≥ 0.85) among forage types. Serum glucose and NEFA concentrations were not influenced (P ≥ 0.61) by supplement type. Circulating SUN concentrations were greater (P < 0.01) in BF-supplemented heifers. Ruminal acetate tended to be greater (P = 0.09) and butyrate concentrations were greater (P < 0.01) for BF-supplemented heifers. The acetate:propionate ratio was not influenced (P = 0.15) by supplement type. These results suggest that a compensatory gain period prior to breeding would be needed for these native warm-season species to be a viable opportunity for growing and developing replacement heifers in the southeastern United States. Department of Animal Science University of Tennessee Departamento de Produção Animal Instituto de Zootecnia UFRRJ – Univ Federal Rural do Rio de Janeiro Department of Plant Sciences University of Tennessee Departamento de Ciências Exatas Faculdade de Ciências Agrárias e Veterinárias UNESP – Univ Estadual Paulista Departamento de Zootecnia Faculdade de Ciências Agrárias e Veterinárias UNESP – Universidade Estadual Paulista West Central Research and Extension Center University of Nebraska Departamento de Ciências Exatas Faculdade de Ciências Agrárias e Veterinárias UNESP – Univ Estadual Paulista Departamento de Zootecnia Faculdade de Ciências Agrárias e Veterinárias UNESP – Universidade Estadual Paulista Natural Resources Conservation Service: 69-3A75-14-257

[Departement_IRSTEA]Territoires [ADD1_IRSTEA]Adaptation des territoires au changement global; International audience; Extreme precipitation events are widely thought to intensify in a warmer atmosphere through the Clausius-Clapeyron equation. The temperature-extreme precipitation scaling was proposed to analyse the temperature dependency of short-duration extreme precipitation and since then, the concept has been widely used in climatology. Bao et al. (2017) suggest that the apparent scaling reflects not only how surface air properties affect extreme precipitation, but also reflects how synoptic conditions and localized cooling due to the storm itself affect the scaling - implying two-way causality. We address here critical issues of this paper and provide evidence that dew point temperature drives extreme precipitation, with the direction of causality reversed only for the storm's peak intensity. This physical inference may serve as a basis to better quantify scaling rates and to help establish the relationship between extreme precipitation and environmental conditions in the current climate, and thereby provide insights into future changes to precipitation extremes due to climate change.

The recent benthic foraminiferal distribution in the Lagoon and Gulf of Venice has been described through the quantitative analysis of about 1000 bottom samples collected in the '80s and '90s. The benthic foraminiferal assemblage shows a high level of uniformity and stability within areas characterised by similar physical and chemical parameters (biotopes). The foraminiferal biotopes have a response time to environmental changes of the order of a few years, so the temporal comparison between biotopes before and after anthropic interventions is particularly useful for applicative approaches. To assess the degree of recent environmental change, the quantitative data have been used for a comparison using the Kolmogorov-Smirnov non-parametric test in two area with great anthropic influence, in the central lagoon and at the Lido Inlet. Between 1980-1990 and 2001 little or no biotope change occurred over more than 50% of the lagoon. On the Lido Inlet a comparison was obtained between samples collected in 1983 and 2006: the high similarity in the foraminiferal assemblages of the two periods strongly suggests that the physical and chemical characteristics, within the sampled area, have not greatly changed during the intervening 23 years. The knowledge of the biotopes distribution gives an overall picture of the characteristics of the Lagoon of Venice and Northern Adriatic Sea for monitoring the effects of the engineering interventions ongoing at the lagoon inlets.

The availability of monitoring techniques that combine the various parameters of the water masses is particularly needed in coastal environments under human pressure. Foraminifera, a Class of the Kingdom PROTOCTISTA secreting a test, are good indicators of the environment in which they live and, through sediment records, they can define the reference conditions of the past. In the Lagoon of Venice, the diffuse presence of salt marshes helped and facilitated the first stable settlements from the first centuries AD. Due to the relative sea level rise, the places were progressively deserted when the practical issues discouraged costly safeguard interventions; conservation and bank rise works where realized only when historical or town-planning issues required the area maintenance. The present legislation is planning the salt marshes defence and the lagoon morphology re-establishment. In this context, the artificial salt marsh of Mazzorbo has been built during the second half of 1999. Its unsuccessful colonisation by foraminifera shows that this artificial salting is out of the natural dynamism proper to the intertidal morphologies and it may be only classified as a land recovery.

From 2003 to 2009 an extensive survey in a large area of the Venice Lagoon was carried out by means of acoustic techniques. The measurements were performed in extremely shallow water (up to 0.5 m). The acoustic data revealed the presence in the sediments of a complex network of buried palaeochannels and palaeosurfaces confirmed by numerous ground truth analyses carried out on the cores extracted in the area. In this note, a high spatial resolution sub-bottom mapping of the central Venice lagoon is presented.

If no conservation work is carried Out, Subsiding coastal areas are prone to progressive submersion by the sea and to changes in their physiographical features. In Italy, the Lagoon of Venice is a Peculiar example on this situation, where the Relative Sea Level Rise (RSLR) is the result of the sea level rise and the land subsidence both natural and man-induced. In non-urbanised areas in the Lagoon, the mean rate of RSLR over the last 5000 years was about 1 mm/year, assuming the lowest figures in the last 1000 years. In built-up areas, where compaction of superficial marshy ground due to huge load of buildings must be added, the rate is between 1 and 2 mm/year. Over the last century, the RSLR has totalled about 23 cm, equal to a mean rate of nearly to 2 mm/year. In the Lagoon of Venice, both natural and anthropogenic evidence of RSLR is revealed in sediments. Natural evidence goes back to the period prior to human settlement, and that due to mail's activities dates back to historical times. The works in question were mainly carried out ill order to avoid having to abandon settlements due to exceptional flooding. In the archaeological areas of the Lagoon, human settlements act as proxies clarifying evolution. In some places, man has abandoned previous settlements: for example, the island of S. Lorenzo was urbanised in the first few centuries AD, remained inhabited until the XIV century, and was then abandoned, due to a new increase in sea level. At other times, man succeeded in preventing this process by infill works, or by raising paved levels above mean sea level, as oil the island of S. Francesco del Deserto, which has been inhabited since the I century AD. Instead, other non-urbanised areas in the Lagoon, such as salt-marshes or beach cordons, have disappeared with the passing of time, and now lie well below mean sea level. This natural situation is clearly testified by foraminifera - useful proxies of past situations of environmental evolution and its local chronology. In the urbanised areas, and chiefly in the historical centre of Venice, buildings have acted as proxies of the RSLR in historical times. In the last 100 years, technical improvements have allowed ground elevation and sea level to be regularly monitored. At present, inside the Lagoon, some areas lying at approximately sea level, such as high marshes, are undergoing a significant increase in flooding, mostly attributable to the RSLR, and are becoming perennially submerged areas due to the lack of intervention. In view of the considerable importance of the city of Venice, much conservation and restoration work is being undertaken, in a everlasting confrontation with the RSLR.