Search results for "Biomas"
showing 10 items of 980 documents
Modelling the optical properties of fresh biomass burning aerosol produced in a smoke chamber: results from the EFEU campaign
2007
A better characterisation of the optical properties of biomass burning aerosol as a function of the burning conditions is required in order to quantify their effects on climate and atmospheric chemistry. Controlled laboratory combustion experiments with different fuel types were carried out at the combustion facility of the Max Planck Institute for Chemistry (Mainz, Germany) as part of the "Impact of Vegetation Fires on the Composition and Circulation of the Atmosphere" (EFEU) project. The combustion conditions were monitored with concomitant CO<sub>2</sub> and CO measurements. The mass scattering efficiencies of 8.9&plusmn;0.2 m<sup>2</sup> g<sup>…
Pretreatment of trace element-enriched biomasses grown on phytomanaged soils for bioethanol production
2017
Abstract Phytotechnologies are a set of sustainable, ecological options notably for alleviating pollutant linkages induced by contaminated soils. However, concerns exist regarding the processing of trace elements (TE)-enriched biomass and the fate of TEs in the end-products. The fractionation of phytoremediation TE-enriched non-woody lignocellulosic (tobacco) and woody (birch, willow) phytoremediation-borne biomasses was studied using ethanol organosolv, soda and dilute acid pretreatments. TE distribution in the process fractions (pulp, liquid effluents and lignin) was further examined. In dilute acid conditions, a wood pretreatment performed at 170 °C in the presence of 2% w/w of sulfuric …
Torrefaction and pyrolysis of metal-enriched poplars from phytotechnologies: Effect of temperature and biomass chlorine content on metal distribution…
2017
Abstract Torrefaction (290 °C) and pyrolysis (450 and 800 °C) trials were performed at pilot scale with a patented reactor on metal-enriched poplars from a contaminated soil managed by phytotechnologies and poplars cultivated on uncontaminated soil, for comparison. This study emphasized the influence of temperature on end-product yield, metal distribution in end-products and metal behavior. Results showed that the evolution of the end-product yield, i.e. biochar, bio-oil and gas fractions, was depending on temperature rather than other parameters such as the origin or metal content of the tested poplars. Torrefaction decreased the processed poplars weight, leading to metal-enriched torrefie…
Caracterisation for ancient wheat varieties for their ability to form mycorrhiza and grain quality impact
2014
Wheat (kind Tritucum aestivum, Poaceae family) is a very important cereal ofagronomic interest. Some very ancient varieties are set aside for recent varieties often selected to meet a consumer intensive cultivation of pesticides. Organic farming production system assuming a reduction of synthetic chemical inputs in order to preserve the ecosystem can be defined as a practice where the use of synthetic fertilizers, chemical pesticides and genetically modified organisms is prohibited. This practice is gaining more and more popularity and the amount of land cultivated in this way has increased by 60% between 2000 and 2004. Constraints associated with the production of organic grains include lo…
Influence de différentes pratiques agricoles sur la qualité et la santé des sols : étude de cas sur des vergers slovènes irrigués ou en agriculture b…
2011
Underestimation of soil properties and poor understanding of soil conditions can have many negative consequences, which results in quality or quantity of yield, soil degradation or even environmental pollution. According to importance of agricultural practices, our study focused on their impact on soil quality and health. The research took place from November 2003 to October 2007 in apple orchards in north-eastern Slovenia where two frequent agricultural practices were investigated: (i) drip irrigation on Calcaric Cambisol and its effects on structural stability and microbial biomass at Gačnik experimental station and (ii) combination of organic fertiliser (Campo guano) and liming in organi…
Effets du cuivre sur quelques indicateurs de la qualité biologique des sols viticoles. Etude à différentes échelles
2008
Des produits à base de cuivre sont utilisés depuis plus d’un siècle en viticulture pour lutter contre le mildiou (et d’autres maladies). Cet élément s’accumule dans le sol, où il peut atteindre des concentrations importantes, susceptibles d’en altérer le fonctionnement biologique. Bien que potentiellement dangereux pour la biocénose des sols, le cuivre est toujours utilisé, notamment en Agriculture Biologique. Dans ce travail, nous avons cherché à préciser les impacts du cuivre sur quelques aspects de la qualité biologique des sols viticoles en conditions « réelles », à court, moyen et long terme. Les effets à long terme ont été appréciés à l’échelle d’une région viticole (la Champagne) à t…
Biogeographical patterns of soil molecular microbial biomass
2011
Affiche - résumé. Session GC: Microbes in the Changing Environmenl: Global Climate Change and Soif under Human Impact; International audience; The spatial organization of soil microbial communities over large areas and the identification of environmental factors structuring their distribution have been liUle investigated. The overall objective of this study was to determine the spatial paUerning of microbial biomass in soils on wide extent and to rank the environmental fiUers most influencing this distribution, by using the French Soil Quality Monitoring Network. This network covers ail the French terrilory and soils were sampled at2,150 sites along a systematic grid sampling. The soil DNA …
Impact assessment of irrigation by treated wastewater on soil bacterial genetic structure diversity of Nabeul-Tunisia irrigated areas
2011
Affiche, résumé. Session AS: Agricullural Soils: Biodiverslly and Functloning; International audience
Gestion des adventices en semis direct : effet des couverts et de leur conduite
2019
National audience; Un essai pluriannuel en semis-direct a testé l’effet de couverts (quatre mélanges comparés à du sol nu) sous divers niveaux de ressources (en azote et en eau) sur la flore adventice et sur les cultures suivantes de la succession (orge de printemps puis lin d'hiver) conduites sans fertilisation et sans désherbage. Une augmentation du nombre d’espèces cultivées dans un mélange ne permet pas de mieux concurrencer les adventices. Un apport d’azote au semis permet au couvert de produire plus de biomasse de couvert mais ne réduit pas le salissement dans le couvert. Comparé à l’action du gel ou au roulage des couverts sur le gel, la destruction chimique du couvert (glyphosate) a…
Digital tools for a biomass prediction from a plant-growth model. Application to a weed control in wheat crop
2019
International audience; Weed control is essential for crop quality and yield. Usually, the main factors affectingdecision-making of farmers in weeding are based on the presence of certain weedvarieties and their density (plants/m2). However, the weed management at the scale ofthe crop cycle refers to other competition indicators, more reliable, such as plantbiomass or leaf area index (LAI). Classically, plant biomass measurements are obtainedby a destructive method of sampling, time consuming and it turns out to be unworkablein practice for farmers. This project proposes to study an innovative method of biomassevaluation which is based on the acquisition of plot images to determine the leaf…