Cu retention in an acid soil amended with perlite winery waste

Environmental Science and Pollution Research (2016), 23, 3789–3798

DOI: 10.1007/s11356-015-5639-4

The effect of perlite waste from a winery on general soil characteristics and Cu adsorption was assessed. The studied soil was amended with different perlite waste concentrations corresponding to 10, 20, 40 and 80 Mg ha−1. General soil characteristics and Cu adsorption and desorption curves were determined after different incubation times (from 1 day to 8 months). The addition of perlite waste to the soil increased the amounts of organic matter as well as soil nutrients such as phosphorus and potassium, and these increments were stable with time. An increase in Cu adsorption capacity was also detected in the perlite waste-amended soils. The effect of perlite waste addition to the soil had special relevance on its Cu adsorption capacity at low coverage concentrations and on the energy of the soil-Cu bonds.

Metalaxyl mobility in acid soils: Evaluation using different methods

International Journal of Environmental Science and Technology 

DOI: 10.1007/s13762-014-0612-1

In the present work, different methods were tested to evaluate the adsorption and desorption of metalaxyl in two acid soils with different organic carbon and clay contents. The three methods (batch, stirred flow chamber and column) that were examined produced similar findings when the two soils were compared: (a) the metalaxyl adsorption capacity was higher in the soil with higher organic matter and clay content, and (b) the soil with the lower organic matter and clay contents provided higher adsorption rate constants. In the two soils tested, the metalaxyl adsorbed in the soil was highly reversible. When only one soil was considered, the different methods yielded different results. The metalaxyl adsorption and its rate were higher with the stirred flow chamber than in the column experiments, and in the column experiments, the total metalaxyl adsorption and the rate of adsorption were higher than in the batch experiments. The percentages of metalaxyl desorbed from the soil were similar in the stirred flow chamber and column experiments, but in the batch experiments, the percentages were significantly lower. In the stirred flow chamber experiments, the desorption processes were faster than the adsorption processes, while in the column experiments, the adsorption and desorption processes exhibited similar rates.

Time evolution of the general characteristics and Cu retention capacity in an acid soil amended with a bentonite winery waste

Journal of Environmental Management

DOI: 10.1016/j.jenvman.2014.12.024

The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80Mgha-1) in laboratory pots, and different times of incubation of samples were tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20Mgha-1, such as an excessive increase of the soil pH and an increase of copper in the soil solution.

Competitive adsorption/desorption of tetracycline, oxytetracycline and chlortetracycline on two acid soils: Stirred flow chamber experiments

Chemosphere, 134 (2015) 361-366

doi 10.1016/j.chemosphere.2015.04.098

The objective of this work was to study the competitive adsorption/desorption of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) on two acid soils. We used the stirred flow chamber technique to obtain experimental data on rapid kinetic processes affecting the retention/release of the antibiotics. Both adsorption and desorption were higher on soil 1 (which showed the highest carbon, clay and Al and Fe oxides content) than on soil 2. Moreover, hysteresis affected the adsorption/desorption processes. Experimental data were fitted to a pseudo-first order equation, resulting qamax (adsorption maximum) values that were higher for soil 1 than for soil 2, and indicating that CTC competed with TC more intensely than OTC in soil 1. Regarding soil 2, the values corresponding to the adsorption kinetics constants (ka) and desorption kinetics constants for fast sites (kd1), followed a trend inverse to qamax and qdmax respectively. In conclusion, competition affected adsorption/desorption kinetics for the three antibiotics assayed, and thus retention/release and subsequent transport processes in soil and water environments.

Kinetics of tetracycline, oxytetracycline, and chlortetracycline adsorption and desorption on two acid soils

Environmental Science and Pollution Research

January 2015, Volume 22, Issue 1, pp 425-433

DOI 10.1007/s11356-014-3367-9

The purpose of this work was to quantify retention/release of tetracycline, oxytetracycline, and chlortetracycline on two soils, paying attention to sorption kinetics and to implications of the adsorption/desorption processes on transfer of these pollutants to the various environmental compartments. We used the stirred flow chamber (SFC) procedure to achieve this goal. All three antibiotics showed high affinity for both soils, with greater adsorption intensity for soil 1, the one with the highest organic matter and Al and Fe oxides contents. Desorption was always <15 %, exhibiting strong hysteresis in the adsorption/desorption processes. Adsorption was adequately modeled using a pseudo first-order equation with just one type of adsorption sites, whereas desorption was better adjusted considering both fast and slow sorption sites. The adsorption maximum (q max ) followed the sequence tetracycline > oxytetracycline > chlortetracycline in soil 1, with similar values for the three antibiotics and the sequence tetracycline > chlortetracycline > oxytetracycline in soil 2. The desorption sequences were oxytetracycline > tetracycline > chlortetracycline in soil 1 and oxytetracycline > chlortetracycline > tetracycline in soil 2. In conclusion, the SFC technique has yielded new kinetic data regarding tetracycline, oxytetracycline, and chlortetracycline adsorption/desorption on soils, indicating that it can be used to shed further light on the retention and transport processes affecting antibiotics on soils and other media, thus increasing knowledge on the behavior and evolution of these pharmaceutical residues in the environment.

Effect of crushed mussel shell addition on bacterial growth in acid polluted soils

Applied Soil Ecology, 85 (2015) 65-68

doi:10.1016/j.apsoil.2014.09.010

We applied three different doses of crushed mussel shell (CMS) on two Cu-polluted acid soils to study the effect of these amendments on the growth of the bacterial community during 730 days. Soil pH increased in the short and medium term due to CMS addition. In a first stage, bacterial growth was lower in the CMS-amended than in the un-amended samples. Thereafter, bacterial growth increased slowly. The soil having the highest initial pH value (4.5) showed the first significant increase in bacterial growth 95 days after the CMS amendment. However, in the soil with the lowest initial pH value (3.8) bacterial growth increased significantly only after 730 days from the CMS addition. The highest dose of CMS caused that, at the end of the incubation period, pH value have increased 2 units, whereas bacterial growth was 4–10 times higher. In view of these results, CMS amendment could be considered as an agronomic sound practice for strongly acid soils (pH <4.5).