Search results for "biodiversity."
showing 10 items of 2292 documents
New Gynandromorph Records for Chirocephalus diaphanus (Branchiopoda, Anostraca, Chirocephalidae)
2021
We report and describe new Chirocephalus diaphanus Prévost, 1803 gynandromorphs from Tunisia and review the literature of anostracan gynandromorphy and other, possibly associated, somatic aberrations, with comments on their evolutionary significance. Our material has three specimens that are specifically deformed on the left side of the head.
Disentangling directional and fluctuating asymmetry in a genome-wide association study.
2018
8 pages; International audience; Although directional and fluctuating asymmetry have been frequently assessed independently, they are indeed associated concepts both in theory and in practice. However, they can be difficult to disentangle in genome-wide association studies, where the appropriate shape statistics are not fully developed. Although the usage of Procrustes distances to overcome this problem may be tempting, this does not reliably help to identify the underlying genetic components of directional and fluctuating asymmetries. Here, similarities and differences among different approaches have revealed that the genetic component of the skull asymmetry in this population of mice is m…
Database Species-Area Relationships in Palaearctic Grasslands
2012
The Database Species-Area Relationships in Palaearctic Grasslands (GIVD ID EU-00-003) is an initiative of the European Dry Grassland Group (EDGG) and primarily functions as repository for all data sampled during the EDGG Research Expeditions. During these expeditions two types of highly standardised sampling of dry grassland vegetation in the Palaearctic realm are carried out: (i) nested-plot sampling on squares of 0.0001, 0.001, 0.01, 0.1, 1, 10, and 100 m2; (ii) additional normal releves of 10-m2 plots. For all plot sizes, the terricolous vascular plants, bryophytes, and lichens are recorded that are superficially present (shoot presence). Additionally, for all 10-m2 plots species cover i…
Effective Practices in Mitigating Soil Erosion from Fields
2017
Soil erosion by water is a natural process that cannot be avoided. Soil erosion depends on many factors, and a distinction should be made between humanly unchangeable (e.g., rainfall) and modifiable (e.g., length of the field) soil erosion factors. Soil erosion has both on-site and off-site effects. Soil conservation tries to combine modifiable factors so as to maintain erosion in an area of interest to an acceptable level. Strategies to control soil erosion have to be adapted to the desired land use. Knowledge of soil loss tolerance, T, i.e., the maximum admissible erosion from a given field, allows technicians or farmers to establish whether soil conservation practices need to be applied …
A soil biodiversity survey coupled with the national soil quality monitoring network?
2021
International audience; Despite its importance for human activities, soil biodiversity remains largely unknown and threatened. Aware of the need for large-scale monitoring, we studied the feasibility to add a soil biodiversity survey (RMBS-Biodiversity) to the already existing French soil quality monitoring network (RMQS). We worked with soil biodiversity experts to couple RMBS-Biodiversity with RMQS i.e. to choose soil taxons and functions, the methodologies and the sampling design. According to the experts, the sampling design of RMQS fits with a soil biodiversitysurvey. We propose sampling protocols for i) bacteria and fungi, ii) protists, iii) nematodes, iv) mesofauna (particularly spri…
Nitrogen-fixing cushion Astragalus siculus modulates soil fertility, microclimate, plant facilitation, bacterial and fungal microbiota along an eleva…
2023
Question: Cushion-forming vascular plants are adapted to alpine environments and act as ecosystem engineers by moderating microclimate and creating a fertility island under their canopy. Most of the available studies on cushion ecology have been devoted to plant facilitation, but none used a holistic approach that considers the response of co-existing plant species with other key ecosystem players. Here, we quantified the biogenic effect and facilitation capacity of Astragalus siculus, a spiny nitrogen-fixing cushion plant, and test the hypothesis that the facilitation effect would increase with elevation as stress gradient.Location: Mount Etna, the highest active volcano in the Mediterrane…
La terre : un bien hors du commun. De l'utopie à la révolution foncière
2018
International audience; La terre manque toujours cruellement d'un droit à sa démesure. Indispensable à la plupart des activités humaines, cette ressource naturelle est saisie par un ensemble disparate de règles au prix, trop souvent, d'une négation de ses qualités. « À vouloir "forcer" la terre, écrivait Pisani, nous prenons, en effet, le risque de la voir se dérober »2. De là, un mal bien terrestre de notre société, qui affecte aussi bien la chose elle-même que ses habitants. Les symptômes portent les noms d'accaparement, d'artificialisation, de surexploitation, de dégradation. Ils sont suffisamment graves pour justifier la création d'un authentique système foncier, projet politique encore…
Global urban environmental change drives adaptation in white clover
2022
Made available in DSpace on 2022-04-28T19:52:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-18 Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied am…
Biodiversity of Sourdough Lactic Acid Bacteria.
2010
Modern technology of baked goods largely uses sourdoughs because of the many advantages offered over baker’s yeast. Sourdough is characterized by a complex microbial ecosystem, mainly represented by lactic acid bacteria (LAB) and yeasts, whose fermentation confers to the resulting product its characteristic features such as palatability and high sensory quality. Raw materials used in baking are not heat-treated; thus, they bring their wild microorganisms to the production process. Investigation of the composition and evolution of microbial communities of sourdough and raw materials is relevant in order to determine the potential activities of sourdough microorganisms. LAB are the main facto…
Probabilistic and preferential sampling approaches offer integrated perspectives of Italian forest diversity
2023
Aim: Assessing the performances of different sampling approaches for documenting community diversity may help to identify optimal sampling efforts and strategies, and to enhance conservation and monitoring planning. Here, we used two data sets based on probabilistic and preferential sampling schemes of Italian forest vegetation to analyze the multifaceted performances of the two approaches across three major forest types at a large scale. Location: Italy. Methods: We pooled 804 probabilistic and 16,259 preferential forest plots as samples of vascular plant diversity across the country. We balanced the two data sets in terms of sizes, plot size, geographical position, and vegetation types. F…