Search results for "amendment"
showing 10 items of 50 documents
Aided phytostabilization using Miscanthus sinensis×giganteus on heavy metal-contaminated soils
2013
Abstract A field experiment was carried out to evaluate the use of red mud, a by-product of the alumina industry, as a soil amendment on highly contaminated soils in the vicinity of a former Pb–Zn smelter in Copșa Mica (Romania). Changes in the distribution of Zn, Cd and Pb in various soil fractions, mobility of heavy metals in the soil, and their uptake and effects on growth and productivity of Miscanthus sinensis × giganteus were evaluated. Uptake of Zn, Cd and Pb was determined in different tissues of M. sinensis × giganteus cultivated in field plots situated at increasing distance from the pollution source and with different levels of contamination and metal availabilities. Soluble meta…
From inequitable to sustainable e-waste processing for reduction of impact on human health and the environment
2021
Recycling of electric and electronic waste products (e-waste) which amounted to more than 50 million metric tonnes per year worldwide is a massive and global operation. Unfortunately, an estimated 70 & ndash;80% of this waste has not been properly managed because the waste went from developed to low-income countries to be dumped into landfills or informally recycled. Such recycling has been carried out either directly on landfill sites or in small, often family-run recycling shops without much regulations or oversights. The process traditionally involved manual dismantling, cleaning with hazardous solvents, burning and melting on open fires, etc., which would generate a variety of toxic sub…
Water dynamics in different biochar fractions
2015
Biochar is a carbonaceous porous material deliberately applied to soil to improve its fertility. The mechanisms through which biochar acts on fertility are still poorly understood. The effect of biochar texture size on water dynamics was investigated here in order to provide information to address future research on nutrient mobility towards plant roots as biochar is applied as soil amendment. A poplar biochar has been stainless steel fractionated in three different textured fractions (1.0–2.0 mm, 0.3–1.0 mm and <0.3 mm, respectively). Water-saturated fractions were analyzed by fast field cycling (FFC) NMR relaxometry. Results proved that 3D exchange between bound and bulk water predominant…
The organic carbon derived from sewage sludge as a key parameter determining the fate of trace metals.
2007
8 pages; International audience; In a sandy agricultural soil of south-west of France, continuously cultivated with maize and amended with sewage-sludge over 20 years, the behavior of three trace metals (Cu, Pb, and Zn) was studied during the sludge applications (1974-1993) and after its cessation (1993-1998). Using the delta13C analysis, the dynamics of different sources of organic matter were followed in order to elucidate the influence of the sludge-derived organic matter on the fate of trace metals in the soil and its particle size fractions. This study revealed that sludge-derived organic matter contributed to the formation of macroaggregates through the binding of preexisting microagg…
Different Type Clay Amendments for Lead Immobilization in Contaminated Soils
2014
Contamination with lead in soil is a crucial problem in industrial and military sites. Immobilization of lead by natural and modified clay as soil amendment can be an effective solution to this problem. Quaternary and Devonian clays were chosen for modification with NaCl, CaCl2, FeOOH and Ca10(PO4)6(OH)2 in different proportions of Ca/P equimolar ratio to test and compare immobilization efficiency of lead (II) on raw and modified clays by using a batch leaching test. The aim of the study is to compare different types of raw and modified clays as soil amendments by lead immobilization properties.
Long-term effects of soil management on ecosystem services and soil loss estimation in olive grove top soils
2016
Soil management has important effects on soil properties, runoff, soil losses and soil quality. Traditional olive grove (OG) management is based on reduced tree density, canopy size shaped by pruning and weed control by ploughing. In addition, over the last several decades, herbicide use has been introduced into conventional OG management. These management strategies cause the soil surface to be almost bare and subsequently high erosion rates take place. To avoid these high erosion rates several soil management strategies can be applied. In this study, three strategies were assessed in OG with conventional tillage in three plots of 1. ha each. Soil properties were measured and soil erosion …
Impact of Innovative Agricultural Practices of Carbon Sequestration on Soil Microbial Community.
2011
This chapter deals with the impact on soil microbiology of innovative management techniques for enhancing carbon sequestration. With in the MESCOSAGR project, the effect of different field treatments was investigated at three experimental sites differing in pedo-climatic characteristics. Several microbiological parameters were evaluated to describe the composition of soil microbial communities involved in the carbon cycle, as well as to assess microbial biomass and activity. Results indicated that both compost and catalyst amendments to field soils under maize or wheat affected microbial dynamics and activities, though with out being harmful to microbial communities.
Soil chemical and biochemical properties of a salt-marsh alluvial Spanish area after long-term reclamation
2009
Marisma, one of the largest salt-marsh alluvial areas in SW Spain, has been reclaimed since 1970 by artificial drainage and amendment with phosphogypsum (PG) so as to reduce Na+ saturation. Within the reclaimed area, two 250- × 20-m plots were treated as follows: (1) amendment with 25 Mg/ha of PG every 2 to 3 years between 1979 and 2003 (plot PY); (2) like PY but PG treatment stopped after 1997 (plot DR). A contiguous virgin Marisma salt-marsh plot (MV), neither drained nor amended, was the control. In MV, soil microbial biomass C, most enzyme activities and total organic C content were much greater than in PY and DR soils, despite the salinity stress. The decrease in soil organic matter co…
Compost Effect on Diuron Retention and Transport in Structured Vineyard Soils
2015
12 pages; International audience; Diuron is frequently detected in surface- and groundwater under the vineyards, where organic amendments are often used, in Burgundy of France. Undisturbed column experiments were conducted to study the influence of three composted organic amendments on diuron leaching through columns of two vineyard soils from Vosne-Romanée (VR, calcareous Cambisol) and Beaujolais (Bj, sandy Leptosol), France. Bromide (used as non-reactive tracer) and diuron breakthrough curves (BTCs) were analyzed using convectivedispersive equation (CDE), two-region (mobile-immobile, MIM) and two-site models. No influence of the composts was observed on the bromide recovery rates. The CDE…
Copper Dynamics and Impact on Microbial Communities in Soils of Variable Organic Status
2008
International audience; The effect of soil organic status on copper impact was investigated by means of a microcosm study carried out on a vineyard soil that had been amended with varying types of organic matter during a previous long-term field experiment. Soil microcosms were contaminated at 250 mg Cu kg−1 and incubated for 35 days. Copper distribution and dynamics were assessed in the solid matrix by a sequential extraction procedure and in the soil solution by measuring total and free exchangeable copper concentrations. Copper bioavailability was also measured with a whole-cell biosensor. Modifications of microbial communities were assessed by means of biomass-C measurements and charact…