Search results for "LiCa"
showing 10 items of 20660 documents
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…
Description de Artareites landii nov. (Ammonoidea) du Barrémien supérieur de Majastre (sud-est de la France) et discussion sur les Helicancylidae Hya…
2009
25 pages; Dans le secteur de Majastre (Alpes-de-Haute-Provence, SE de la France), le domaine hémipélagique du Crétacé inférieur est exposé à la faveur du décrochement du Poil. Cette position paléogéographique et paléotectonique a permis la récolte d'une faune d'ammonites diversifiée dans le niveau à « petits Barremites ». Il est précisément daté ici pour la première fois et se place entre la base de la sous-zone à Barremense et la base du biohorizon à Breistrofferi de la biozone à Vandenheckei (base du Barrémien supérieur). Au sein de cette faune, Artareites landii nov. sp. est considéré ici, par ses caractéristiques et sa position stratigraphique, comme issu du genre Dissimilites Sarkar. L…
Systematic review of the effects of chemical insecticides on four common butterfly families
2017
Safeguarding crop productivity by protecting crops from pest attacks entails the wide use of plant protection products that provide a quick, easy and cheap solution. The objective of this study is to understand the effects of insecticides used in agriculture on non-target butterflies, specifically on the families Lycaenidae, Nymphalidae, Hesperiidae, and Papilionidae. To achieve this goal, a formal systematic review was performed according to European Food Safety Authority (EFSA) guidelines, by entering a combination of keywords on 3 online databases. Three reviewers independently extracted information on study characteristics and quality. The main results were collected and grouped by the …
Stochastic models for phytoplankton dynamics in Mediterranean Sea
2016
Abstract In this paper, we review some results obtained from three one-dimensional stochastic models, which were used to analyze picophytoplankton dynamics in two sites of the Mediterranean Sea. Firstly, we present a stochastic advection–reaction–diffusion model to describe the vertical spatial distribution of picoeukaryotes in a site of the Sicily Channel. The second model, which is an extended version of the first one, is used to obtain the vertical stationary profiles of two groups of picophytoplankton, i.e. Pelagophytes and Prochlorococcus, in the same marine site as in the previous case. Here, we include intraspecific competition of picophytoplanktonic groups for limiting factors, i.e.…
The Italian Loci Classici Census
2012
Values and challenges in the assessment of coprophilous fungi according to the IUCN Red List criteria: the case study of Poronia punctata (Xylariales…
2020
Coprophilous fungi are specialized microorganisms, playing key roles in ecosystems and in several other contexts, whose protection requires more substantial efforts. This paper aims to highlight and discuss valuable and critical aspects faced during the process of the threat status assessment of Poronia punctata, providing inspirations for future conservation actions.
Rhynchophorus ferrugineus: Behavior, Ecology, and Communication
2017
Red palm weevil (RPW) ecology is characterized by the adults' ability to aggregate on palms. The aggregation process has the functions of protection, feeding, and reproduction for the individuals. Semiochemicals and visual cues strongly influence this behavior at intraspecific and interspecific levels. Adults actively fly over long distances, following chemical cues, such as aggregation pheromone and host plant odor, or visual cues to colonize a new host. The aggregation pheromone of RPW is a male-produced mixture of 4-methyl-5-nonanol (major component) and the related ketone 4-methyl-5-nonanone (minor component). These compounds are largely used in the field to lure males and especially fe…
Volatile-mediated foraging behaviour of three parasitoid species under conditions of dual insect herbivore attack
2016
Infochemicals play an important role in structuring intra-and interspecific interactions. Many parasitoid wasp species rely on herbivory or oviposition-induced plant volatiles (HIPVs/OIPVs) to locate their herbivorous hosts, and must cope with variation in the volatile blends due to factors such as plant/host species, herbivore density or attack by several herbivores. However, little is known about how dual herbivory or changes in herbivore density affect multiple parasitoid species, each attacking a different herbivore, in the same system. In a natural system, we investigated the effect of dual attack on the ability of three parasitoid species to differentiate between volatiles induced by …
Paysandisia archon: Behavior, Ecology, and Communication
2017
This chapter on Paysandisia archon behavior, ecology, and communication is presented in three parts. The first part deals with reproductive behavior and the sex pheromone. In this section, mating behavior is described with a consideration of optimal age and diel periodicity. Early observations have shown that mating can occur a few hours after adult molting, from noon to the beginning of the afternoon, according to timing of emergence. The female is described as flying close to perching males and the pair then fly together before mating. The male exhibits a scratching movement with the mid-legs while the female extrudes the abdominal tips. Putative sex pheromone production is discussed in r…
Effects of water stress on emission of volatile organic compounds by Vicia faba, and consequences for attraction of the egg parasitoid Trissolcus bas…
2017
When plants are damaged by herbivorous insects, blends of volatile organic compounds (VOCs) are induced and released and can also be used by parasitoids to locate hosts. The aim was to determine whether VOCs induced by water stress affect the plant-herbivore-para- sitoid system represented by broad bean (Vicia faba; Fabales: Fabaceae) stink bug (Nezara viridula; Hetero- ptera: Pentatomidae) egg parasitoid (Trissolcus basalis; Hymenoptera: Platygastridae). The effects of water stress (expressed as the percentage fraction of transpirable soil water [FTSW] supplied) alone and in combination with N. viridula damage (feeding plus oviposition) were deter- mined according to: (1) the behavioural r…