Search results for "TEA"
showing 10 items of 7074 documents
Classification of steppe vegetation in the eastern Pamir Alai and southwestern Tian-Shan Mountains (Tajikistan, Kyrgyzstan)
2018
Aims: To complete the syntaxonomical scheme for the steppe vegetation of the montane and alpine zones in the Pamir Alai and southwestern Tian-Shan Mountains in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. Location: Tajikistan and Kyrgyzstan. Methods: A total of 274 relevés were sampled in 2016–2017 using the seven-degree cover-abundance scale of Braun-Blanquet. They were classified with modified TWINSPAN with cut-off levels of 0%, 5%, 10% and 25% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Detrended correspondence analysis (DCA) and canonical correspondence analys…
Dwarf shrub vegetation of rock ledges and clefts in the Pamir Alai Mountains (Middle Asia: Tajikistan)
2016
AbstractThe paper presents the results of phytosociological researches on rocky slope vegetation in Tajikistan with the aim to establish a comprehensive syntaxonomical classification system. Field studies were conducted in 2010-2014 in Pamir Alai ranges and Pamirian plateau. Nearly 500 relevés documenting rock and scree vegetation were made according to the Braun-Blanquet method. Numerical analyses of selected 58 relevés representing dwarf shrub vegetation on rock ledges made it possible to distinguish: Ephedro glaucae- Spiraeion baldschuanicae and Ephedrion regeliano-fedtschenkoi alliances, as well as Spiraeetum baldschuanicae, Rhamnetum coriaceae, Pentaphylloidetum parvifoliae and Pentaph…
The Function of Stones in Nest Building: The Case of Black Wheatear (Oenanthe Leucura) revisited
2016
Black Wheatears ( Oenanthe leucura) transport to breeding territories, including the nest, a large number of stones. Currently, there is negative evidence that stones serve for nest support, thermoregulation, weather protection or anti-predation, but in males, this behaviour appears to represent a form of post-mating display. This ‘sexual selection’ hypothesis, however, does not explain why females also carry stones, and why many stones are associated with the nest. We examined stone distribution and morphology in 277 abandoned nests of Black Wheatears from an arid area of southeastern Spain. Nests were built on the ground (14.4%), or in cracks (7.2%), cavities (54.6%) and ledges (23.8%) a…
Interactions between dark septate endophytes, ectomycorrhizal fungi and root pathogens in vitro
2019
ABSTRACT Dark septate endophytes (DSEs) are widely distributed worldwide and can promote plant growth. Therefore, they are considered potentially important plant allies, especially in stressful environments. Previous studies have reported that DSEs cohabit roots with other microorganisms such as ectomycorrhizal (ECM), endophytic and pathogenic fungi/oomycetes. However, interactions between different DSE species have not yet been reported, and studies on the interactions between DSEs and other fungi are scarce. Using a simple and reproducible pairwise growth assay in vitro, we studied the synergistic/antagonistic interactions between eight DSEs, two ECM fungi and three root pathogens. Most o…
“Into and Out of” the Qinghai‐Tibet Plateau and the Himalayas: Centers of origin and diversification across five clades of Eurasian montane and alpin…
2020
Abstract Encompassing some of the major hotspots of biodiversity on Earth, large mountain systems have long held the attention of evolutionary biologists. The region of the Qinghai‐Tibet Plateau (QTP) is considered a biogeographic source for multiple colonization events into adjacent areas including the northern Palearctic. The faunal exchange between the QTP and adjacent regions could thus represent a one‐way street (“out of” the QTP). However, immigration into the QTP region has so far received only little attention, despite its potential to shape faunal and floral communities of the QTP. In this study, we investigated centers of origin and dispersal routes between the QTP, its forested m…
The role of noise on the steady state distributions of phytoplankton populations
2016
The spatio-temporal behaviour of total chlorophyll concentration is investigated in the middle of the Tyrrhenian Sea by using a stochastic approach. The study is based on a reaction-diffusion-taxis model, which is used to analyse the dynamics of five phytoplankton groups, responsible for about 80% of the total chlorophyll a inside the euphotic zone of the water column. The analysis is performed by considering: (i) the intraspecific competition of the phytoplanktonic groups for limiting factors, i.e. light intensity and nutrient concentration, (ii) the seasonal changes of environmental variables, and (iii) the random fluctuations of the components of the velocity field and temperature. Speci…
Reviewing research priorities in weed ecology, evolution and management: a horizon scan.
2018
Weedy plants pose a major threat to food security, biodiversity, ecosystem services and consequently to human health and wellbeing. However, many currently used weed management approaches are increasingly unsustainable. To address this knowledge and practice gap, in June 2014, 35 weed and invasion ecologists, weed scientists, evolutionary biologists and social scientists convened a workshop to explore current and future perspectives and approaches in weed ecology and management. A horizon scanning exercise ranked a list of 124 pre-submitted questions to identify a priority list of 30 questions. These questions are discussed under seven themed headings that represent areas for renewed and em…
Modulation of copper deficiency responses by diurnal and circadian rhythms in Arabidopsis thaliana
2015
Highlight Cyclic expression of copper transport and the responses to copper deficiency are integrated into the light and circadian–oscillator signalling in plants.
En quin grau afecten les pseudociències a la comunitat educativa?
2018
Pseudosciences are present and accepted naturally by broad sectors of the population. Despite their potential risks, they are not taken into account when teaching science; some universities have even offered official pseudoscientific courses. In this text we want to learn about the degree of acceptance of these beliefs in high-school science teachers in training, who have been detected to have significant levels of acceptance of pseudoscience.
Antiviral and antioxidant properties of active alginate edible films containing phenolic extracts
2018
In this work, novel active edible films having antiviral activity were developed through the solvent casting method. Emulsified edible films were prepared by adding lipids into alginate films in order to improve their water vapour permeability. In addition, two natural extracts rich in phenolic compounds, specifically a green tea extract (GTE) and a grape seed extract (GSE) were used as active agents. Interestingly, incorporating GTE or GSE within the biopolymer matrix, the films exhibited significant antiviral activity against murine norovirus (MNV) and hepatitis A virus (HAV) since ∼2 log reduction were recorded for the 0.75 g extract/g alginate in the film, being GTE more efficient than …