Search results for "engineering.material"

The Mid-Cenomanian Event in southeastern France: evidence from palaeontological and clay mineralogical data.

2013

16 pages; International audience; Reconstruction of main palaeoenvironmental conditions across the Mid-Cenomanian Event (MCE I) in the hemipelagic Tethyan section of Blieux (Southeast France, Vocontian Basin) is proposed. Quantitative analyses of calcareous nannofossil, ammonoid and clay mineral assemblages have been made and compared with respect to sea level changes and the carbon cycle perturbations. The nannofossil primary productivity, as recorded by nannofossil fluxes and relative abundances of meso-eutrophic taxa, is low just below and during the MCE Ia, then slightly increases in the interval including the MCE Ib. The clay assemblages mainly consist of illite/smectite mixed-layers w…

Late Jurassic palaeoclimatic change from clay mineralogy and gamma-ray spectrometry of the Kimmeridge Clay, Dorset, UK

2009

Abstract: The Late Jurassic was a time of increasing aridity in NW Europe. Here, a new clay mineral dataset is presented from a 600 m thick composite core through the Kimmeridge Clay Formation, southern England. Clay mineral assemblages comprise mainly illite and kaolinite, with minor randomly interstratified illite–smectite mixed-layer clays. SEM observations indicate that clay minerals are mainly detrital, except in silty strata of late Tithonian age, which contain abundant pore-filling kaolinite aggregates. Th/K ratios determined from gamma-ray spectrometry mirror palaeoclimatically significant variations in kaolinite/illite ratios, with notable exception where diagenetic kaolinite occur…

The responses of shoot-root-rhizosphere continuum to simultaneous fertilizer addition, warming, ozone and herbivory in young Scots pine seedlings in …

2017

Abstract It is not clear how climate change in combination with increasing soil nitrogen availability and herbivory affects boreal forests, the largest terrestrial biome in the world. In this study, Scots pine ( Pinus sylvestris ) seedlings were exposed to moderate warming (ca. 1 °C), 1.5 × ambient ozone (O 3 ) concentration, fertilizer addition (120 kg N ha −1 yr −1 ) and shoot herbivory by pine sawfly ( Acantholyda posticalis ) alone and in combination. We measured fine root morphology, mycorrhizal colonization level, root fungal biomass (ergosterol), rhizosphere emission of biogenic volatile organic compounds (BVOCs), and microbial biomass (PLFAs) in the rhizosphere soil as well as seedl…

Use of plant growth-promoting rhizobacteria (PGPR) and organic fertilization for soilless cultivation of basil

2021

Abstract Today there is a greater environmental and ecological awareness and it is growing the number of farmers who want to adopt sustainable and efficient cultivation systems even if not officially certified as organic. Sustainable and modern cultivation systems must involve organic fertilization and cannot ignore the role of rhizosphere microorganisms. Starting from this premise, this paper aimed to evaluate the use of plant growth-promoting rhizobacteria (PGPR) and organic liquid fertilizers on soilless cultivation of basil. Genovese basil plants were cultivated in pots filled with a substrate inoculated or not with a commercial biostimulant (TNC BactorrS13) containing growth-promoting …

2019

Street greeneries and other green spaces within the urban matrix can potentially reduce air pollution and increase urban biodiversity. Yet, these services can be negatively affected by anthropogenic stress factors. In the boreo-nemoral zone, large amounts of salts are spread each year for deicing the pavement. To address the effect of deicing salt on street lines of lime trees and how this cascades up to influence the surrounding arthropod biodiversity, we compared heavily salt-polluted and less polluted sites in the city of Riga, Latvia. We analyzed the impairment of foliar functions and development of aphids’ colonies using a common garden experiment. We found marked variation in the soil…

Effect of fruit-set time on the quality performance of Anona cherimola Mill. fruit in south italy

2019

Abstract The aim of this work was to analyse the differences between fruits obtained by different dates of fruit set and identify the proper fruit-set time that allows to obtain the optimum fruit quality in Annona cherimola cv Fino de Jete, planted in Southern Italy. Six fruit-set dates were selected from the first week of June to the second week of July. Fruits were sampled from October to November, when 1500 Growing Degree Days (DD) were accumulated; The DD were calculated using a base temperature of 12 °C. Fruit fresh weight (FW) and skin colour were measured. These parameters were measured also after storage, and in addition, the following parameters were measured: fruit shape (FS), pul…

Long-term effects of no tillage treatment on soil N availability, N uptake, and 15N-fertilizer recovery of durum wheat differ in relation to crop seq…

2016

Abstract No tillage (NT) soil management has largely been promoted because of its potential to generate both economic and environmental benefits. However, it often leads to reductions in crop yield and quality, which in many cases have been attributed to the effects this technique has on the nitrogen (N) dynamics in the soil–plant system. This 2-year study, performed within a long-term experiment in which NT was continuously applied for over 15 years, aimed to verify whether and to what extent the use of NT affects soil N availability, recovery of 15 N-labeled fertilizer, and N use efficiency (NUE) and its components (N uptake efficiency, NUpE; N utilization efficiency, NUtE). Durum wheat w…

Postharvest Application of Aloe vera Gel-Based Edible Coating to Improve the Quality and Storage Stability of Fresh-Cut Papaya

2020

Ready-to-eat products are damaged by various factors, including exposure to O2 and CO2, extreme temperatures, and rapid decay, due to trauma during processing. The use of natural antimicrobial agents and antioxidants might extend the shelf-life of the fruits. The aim of this work is to investigate the effects of four different antibrowning and gelling agents added into the Aloe vera gel-based edible coatings and applied to fresh-cut papaya. EC1 treatment consists of Aloe vera gel (30% v/v), EC2 contains CaCl2 (5% v/v), EC3 contains K carrageenan (0.5% v/v), and EC4 contains sodium alginate (1.5% v/v) and K carrageenan (0.5% v/v). The fruits treated with EC2 showed the best results while mai…

Climate Warming as a Possible Trigger of Keystone Mussel Population Decline in Oligotrophic Rivers at the Continental Scale

2018

AbstractThe effects of climate change on oligotrophic rivers and their communities are almost unknown, albeit these ecosystems are the primary habitat of the critically endangered freshwater pearl mussel and its host fishes, salmonids. The distribution and abundance of pearl mussels have drastically decreased throughout Europe over the last century, particularly within the southern part of the range, but causes of this wide-scale extinction process are unclear. Here we estimate the effects of climate change on pearl mussels based on historical and recent samples from 50 rivers and 6 countries across Europe. We found that the shell convexity may be considered an indicator of the thermal effe…

Characterization of MRNP34, a novel methionine-rich nacre protein from the pearl oysters

2012

9 pages; International audience; Nacre of the Pinctada pearl oyster shells is composed of 98% CaCO(3) and 2% organic matrix. The relationship between the organic matrix and the mechanism of nacre formation currently constitutes the main focus regarding the biomineralization process. In this study, we isolated a new nacre matrix protein in P. margaritifera and P. maxima, we called Pmarg- and Pmax-MRNP34 (methionine-rich nacre protein). MRNP34 is a secreted hydrophobic protein, which is remarkably rich in methionine, and which is specifically localised in mineralizing the epithelium cells of the mantle and in the nacre matrix. The structure of this protein is drastically different from those …