Search results for "Soil CO"
showing 10 items of 269 documents
Wet-up response of the microbial community is shaped by soil dry-down patterns
2015
Background/Question/Methods The massive soil CO2 efflux associated with rewetting dry soils after the dry summer period significantly contributes to the annual carbon budget of Mediterranean grasslands. Rapid reactivation of soil heterotrophic activity and available carbon are both required to fuel the CO2 pulse. Better understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting future changes in carbon cycling. We investigated the effects of a controlled rewetting event on the soil CO2efflux pulse and on the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in int…
Changing summer precipitation pattern alters microbial community response to fall wet-up in a Mediterranean soil
2014
The large soil CO2 efflux associated with rewetting dry soils after the dry summer period significantly contributes to the annual carbon budget of Mediterranean grasslands. Rapid reactivation of soil heterotrophic activity and a pulse of available carbon are both required to fuel the CO2 pulse. Better understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting future changes in carbon cycling. Here, we investigated the effects of a controlled rewetting event on the soil CO2 efflux pulse and on the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in intact soil cor…
Weed flora evolution in direct seeding under cover systems
2018
Direct seeding under cover, by its emergent properties, raises new questions of research on weed communities. The absence of soil disturbance and the implementation of cover crops, modify all factors of conventional agriculture and lead to a complete change of habitat for and management of the weed flora. In addition, these systems allow the development of a certain number of animal communities that interact with one another and with plant communities and thus potentially promote the regulations expected in Agroecology. Finally, there is the issue of annual weed species diversity in systems where tillage is strongly reduced. This thesis, started in November 2017, has as main objective to pr…
Weed flora evolution in direct seeding under cover systems
2019
Since the beginning of agriculture, farmers have been working the soil to produce. With the apparition of mechanization (development of plow coupled to tractors in the early 20th century), this practice has intensified and widespread on all farms. However, in France, since the 2000s, more and more farmers are questioning the utility of working the soil to produce. A new form of agriculture has appeared; the direct seeding under cover which groups together a set of cropping systems that meet certain requirements: no tillage, maximum vegetation cover and diversified rotation. By its emergent properties, this new form of agriculture raises new questions of research that mobilize both agronomy …
Diversity and complexity of microbial communities from a chlor-alkali tailings dump
2015
Abstract Revegetation of the tailings dumps produced by various industrial activities is necessary to prevent dust storms and erosion and represents a great challenge for ecological restoration. Little is known about the microbial colonisation and community structure of revegetated tailings following site exploitation. Here, we report the sequencing of 16S rRNA and internal transcribed spacer (ITS) fungal RNA gene amplicons from chlor-alkali residue and from an adjacent undisturbed soil to define the composition and assembly of the rhizosphere microbial communities. After quality filtering, a total of 72,373 and 89,929 bacterial sequences and 122,618 and 111,209 fungal sequences remained fo…
Protection de la ressource en eau du bassin de l’Auxerrois et transformation des pratiques agricoles
2022
Avec des taux de nitrates dépassant les seuils définis par la Directive européenne « nitrates », puis la présence de résidus de pesticides utilisés par les activités agricoles du secteur, l’eau des bassins d’alimentation de captages de l’Auxerrois fait l’objet de préoccupations depuis une trentaine d’année. C’est ainsi qu’à la fin des années 1990, les représentants des pouvoirs publics ont choisi de mettre en place une démarche préventive passant par un travail de transformation des pratiques agricoles. Notre article analyse comment la prise en charge collective de cette situation participe à la configuration des relations entre représentants des pouvoirs publics, agriculteurs et défenseurs…
Soil, pasture and animal products quality
2013
The management of pasture, through the use of appropriate stocking rates and grazing systems, influences the feeding behaviour of the animals. The impact of animal behaviour on vegetation can be of great importance for the sustainability of pastures and mantaining their biodiversity. Indeed, a different response in terms of quality of animal products is mediated by the ability of animals to concentrate or transform grass components, according to the characteristics of the soil. The herbage ingested by animals provides them with compounds with aromatic characteristics, such as terpenes, and with functional properties beneficial for human health, such as carotenoids, vitamins, polyphenols and…
Bioaccumulation of organochlorine compounds in earthworms
1992
Abstract Bioaccumulation of chlorophenolic wood preservatives 2,3,4,6-tetrachlorophenol (2346-TeCP) and pentachlorophenol (PeCP) and their metabolites in earthworms were studied in the laboratory, and by taking worm samples from the contaminated soil of a sawmill which was abandoned 28 yr ago. In two laboratory experiments 2346-TeCP (containing PeCP as impurity) was added into the soil, and samples were taken at certain intervals both from the soil and the earthworms ( Lumbricus rubellus in experiment 1 and Aporrectodea caliginosa tuberculata in experiment 2). Considerable amounts of chlorophenols were found in field samples. Soil concentrations ranged from 157 to 338 μg 2346-TeCP g −1 dry …
Impact Assessment of Skidding Extraction: Effects on Physical and Chemical Properties of Forest Soils and on Maple Seedling Growing along the Skid Tr…
2019
Several studies investigated soil disturbances caused on skid trails by forest logging. However, there is still a lack of knowledge about the severity and the distance of disturbances along both sides from the trails. The aims of this study were: i) to investigate the changes in physical and chemical properties of soil along the sides of skidding trails
The history of human-induced soil erosion: Geomorphic legacies, early descriptions and research, and the development of soil conservation—A global sy…
2013
Abstract This paper presents a global synopsis about the geomorphic evidence of soil erosion in humid and semihumid areas since the beginning of agriculture. Historical documents, starting from ancient records to data from the mid-twentieth century and numerous literature reviews form an extensive assortment of examples that show how soil erosion has been perceived previously by scholars, land surveyors, farmers, land owners, researchers, and policy makers. Examples have been selected from ancient Greek and Roman Times and from central Europe, southern Africa, North America, the Chinese Loess Plateau, Australia, New Zealand, and Easter Island. Furthermore, a comprehensive collection on the …