Search results for "ORGANIC MATTER"

Lien entre la diversité microbienne, la stabilité des communautés microbiennes et le turnover des matières organiques du sol

2014

Soil microbial communities act as important agents of the biological soil functioning, particularly through their involvements in the transformations of biogeochemical cycles (C, N, P…). In agro-ecosystems, the diversity of these communities is affected by perturbations associated to agricultural practices, and the significance of these modifications in terms of preservation of biological functioning and sustainability of agricultural systems has emerged as a central issue in the environmental sciences. Whereas the role of biodiversity has been well studied for macroorganisms, in particular for plants; the biodiversity/activity relationship is still largely unknown for soil microorganisms. …

Isotopic Differentiation (13C) of Dissolved Organic Carbon and CO2 During Organic Matter Degradation in Forest Soils: Influence of Vegetation

2008

International audience

Distribution and sources of bulk organic matter (OM) on a tropical intertidal mud bank in French Guiana from elemental and isotopic proxies

2014

International audience; The mobile French Guiana coast is a shoreface region downdrift of the Amazon River, where enormous quantities of inorganic and organic materials are exchanged with the Atlantic Ocean. The rapid accumulation of these materials forms highly unstable shore-attached mud banks, which can be temporally emerged and then rapidly colonized and stabilized by microphytobenthos and opportunistic mangroves (i.e. Avicennia germinans). Mud banks are preferential sites for the accumulation and significant remineralization of organic matter (OM) due to intense erosion/deposition cycles and potential biological colonization. The distribution and sources of bulk sedimentary OM were cha…

Ash in composting of source-separated catering waste.

2004

Our earlier experiments in small composters (220 l) indicated the favourable effect of ash from co-incineration of sorted dry waste on the composting of catering waste. The aim of this new study was to clarify further, at a scale of 10 m3, the feasibility of using similar ash as an additive in composting.Source-separated catering waste was mixed with bulking agent (peat and wood chips) and fuel ash from a small (4 MW) district heating power plant. Three compost mixes (CM) were obtained: CM I with 0%, CM II with 10% and CM III with 20 wt.% of fuel ash. These three different mixes were composted in a 10-m3 drum composter as three parallel experiments for 2 weeks each, from January to April 20…

Biostimulant Potential of Humic Acids Extracted From an Amendment Obtained via Combination of Olive Mill Wastewaters (OMW) and a Pre-treated Organic …

2018

Olive mill wastewaters (OMW) detain contain significant levels of phenolic compounds with antimicrobial/phytotoxic activity and high amounts of undecomposed organic matter that may a high pollutant load that exerts negative effects on soil biology because of significant levels in phenolic compounds with antimicrobial/phytotoxic activity and limited biodegradability, and high amounts of undecomposed organic matter. Among OMW detoxification techniques, those focusing on oxidative degradation of phenolic compounds are relevant those focusing on oxidative degradation of phenolic compounds to reduce their toxicity. The composting (bio-oxidation) process in particular, exploits exothermic oxidati…

The fate of terrestrial and riverine materials in a Mediterranean seagrass bed

2009

Molecular Signatures of Biogeochemical Transformations in Dissolved Organic Matter from Ten World Rivers

2016

Rivers carry large amounts of dissolved organic matter (DOM) to the oceans thereby connecting terrestrial and marine element cycles. Photo-degradation in conjunction with microbial turnover is considered a major pathway by which terrigenous DOM is decomposed. To reveal globally relevant patterns behind this process, we performed photo-degradation experiments and year-long bio-assays on DOM from ten of the largest world rivers that collectively account for more than one-third of the fresh water discharge to the global ocean. We furthermore tested the hypothesis that the terrigenous component in deep-sea DOM may be far higher than biomarker studies suggest, because of the selective photochemi…

Global warming affect Collembola community: A long-term study

2006

Summary Long-term (1992–2002) effects of climate changes on soil Collembola in Scots pine Pinus sylvestris forests in North Vidzeme Biosphere Reserve (northern Latvia) are investigated. The study was carried out in three forest stands of different age, young (30–40 years), middle aged (50–70 years), and old (150–200 years). One hundred soil samples were collected within each sampling site once a year in autumn over a period of 11 years. In total, 66 species of Collembola were found. Species richness varied between 47 and 56 and density of Collembola from 7300 to 8300 ind m−2. A statistically significant increase in the sums of positive air temperatures (⩾4 °C) was recorded during the period…

Effects of tilling methods on soil penetration resistance, organic carbon and water stable aggregates in a vineyard of semiarid Mediterranean environ…

2018

Tillage, especially in semiarid Mediterranean environment, enhances the mineralization process of soil organic matter (SOM) and, in turn, decreases aggregate stability. Furthermore, continuous tillage leads to the formation of plough pan beneath the tilled layer. In the present study, we investigated the effect of an innovative self-propelled machine (spading machine, SM) for shallow tillage on SOM, water stable aggregates (WSA) and soil penetration resistance (PR). Such effects were compared to those of chisel plough (CP), rotary tiller (RT) and no tillage (NT). Each tilling method was applied up to a depth of 15 cm, whereas in NT only a brush cutter was used for weed control. Soil analyse…

Tillage effects on yield and nitrogen fixation of legumes in Mediterranean conditions

2012

Published in Agron. J. 104:1459–1466 (2012) Posted online [DATE] doi:10.2134/agronj2012.0070 Copyright © 2012 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. I agricultural practices that involve the use of agrochemicals such as fertilizers, pesticides, and herbicides have greatly increased the global food supply but often with detrimental effects on the environment, such as contamination of ground…