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Biological Activity in a Degraded Alfisol Amended with Sewage Sludge and Cropped with Yellow Serradela (Ornithopus compressus L.)
Celis H,José; Machuca H,Angela; Sandoval E,Marco; Morales C,Patricia;
Chilean journal of agricultural research , 2011, DOI: 10.4067/S0718-58392011000100020
Abstract: there are few studies about the impact of sewage sludge on the biological properties in alfisols of the chilean coastal range drylands. hence, the objective of this study was to evaluate its effect on the microbial respiration and enzymatic activities of a degraded alfisol located in the bío bío region (chile) that was cropped with yellow serradela (ornithopus compressus l.). sludge was added to the soil at rates of 15, 30, and 60 t ha-1; he following treatments were defined: l15-p = 15 t ha-1 sludge + o. compressus; l30-p = 30 t ha-1 sludge + o. compressus; l60-p = 60 t ha-1 sludge + o. compressus; l15 = 15 t ha-1 sludge; l30 = 30 t ha-1 sludge; l60 = 60 t ha-1 sludge; cp = non-amended soil, cropped; and c = non-amended soil, no crop. soil microorganism activity was evaluated by respirometry. hydrolytic enzyme activity representative of soil c, n, and p cycles was determined. crop phytomass development was also evaluated. the amount of c-co2 produced by soil microorganisms was directly proportional to the dose of amended sludge (p ≤ 0.05). similarly, greater β-glucosidase, urease, and acid phosphatase were more active at 60 t sludge ha-1. however, both respiratory and enzymatic activities were greater (p ≤ 0.05) in treatments with sludge-amended soil cropped with o. compressus. this greater activity was notorious when the legumes achieved greater phytomass development, thus highlighting the root?s stimulating effect on soil biological activity.
Study of heavy metal in sewage sludge and in Chinese cabbage grown in soil amended with sewage sludge
P Wang, S Zhang, C Wang, J Hou, P Guo, Z Lin
African Journal of Biotechnology , 2008,
Abstract: The study was performed to investigate the heavy metal content and availability for crops in sewage sludge and its accumulation in Chinese cabbage grown in sewage sludge amended soil. We determined the total and chemical fraction of As, Cr, Cd, Pb, Ni, Cu, Zn, Fe, Mg and Mn in sewage sludge and the total content of these metals in Chinese cabbage grown in soil amended with sewage sludge. Total content of all metals (except for As) was below the top limits for land application of sewage sludge in China. The majority of As, Cd, Pb, Zn and Fe was present in the residual fraction (70 – 95%) of the total concentration, and 21% of Cd, 59% of Cr and 56% of Cu were present in oxidizable fraction in sewage sludge. Most of the content of metals increased in Chinese cabbage with the increase in sludge amendments ratio, and the content of heavy metal As, Cd, Cr and Zn exceeded the top limits of metals content in China. Our results suggested that application of sewage sludge could enhance the output of vegetable while the risk of heavy metal should be of concern.
Microbiological indices of soil quality fertilized with dairy sewage sludge
S. Jezierska-Tys,M. Fr???…c
International Agrophysics , 2008,
Abstract: The study was performed on a pot experiment in which a grey-brown podzolic soil was amended with two different doses of dairy sewage sludge (30 and 75 t ha-1) – 1 and 2.5% of DSS. During periode of incubation in different terms of analyses (7, 14, 30, 60, 90 and 120 days after the incorporation of dairy sewage sludge) the following analyses were done: so-called total number of bacteria, so-called total number of filamentous fungi, number of cellulolytic bacteria, respiration activity and dehydrogenase activity. Dairy sewage sludge applied to the soil caused stimulation of the total number of bacteria, fungi and cellulolytic bacteria and respiration activity and inhibition of dehydrogenase activity in a grey-brown podzolic soil.
Study of the Mobility of Heavy Metals in Soil Amended with Sewage Sludge  [PDF]
J. Nouri,B. J. Alloway,P.J. Peterson
Pakistan Journal of Biological Sciences , 2001,
Abstract: Duplicate (250g) samples of air dried sewage sludge / mixtures in different percentages were placed in sintered glass to conduct a study of the mobility of heavy metals in soil amended with sewage sludge. The pH values of saturation extracts showed an increase in all sample mixtures up to 3rd month. The concentrations of nickel in the extracts were higher than those of cadmium and lead. There was a marked depletion in levels of metals with time, thus showing that the greatest release of metals occurred in the early stages after mixing probably due to the flushing out of the initial soluble forms already present in sludge. Another possibility could be that the decrease in metal concentrations with time could be due to the development of anaerobiosis.
Drug-Resistant Microorganisms in Soils Fertilized with Sewage Sludge
Ewa Stańczyk-Mazanek , Teresa Nalewajek , Magdalena Zabochnicka
Archives of Environmental Protection , 2012, DOI: 10.2478/v10265-012-0008-6
Abstract: One of the methods of sewage sludge disposal, which is based on its fertilizing properties, is its use in nature, e.g. in farming (if all the permissible standards are met). However, the sludge used for soil fertilization might also contain heavy metals, pathogenic microorganisms, thus causing contamination in soil foundation and deterioration of the conditions for development of indigenous organisms. Particular threat is posed by the existence of drug-resistant microorganisms in sewage sludge. This problem has not been researched in detail yet. The authors of the present study aimed to determine qualitative changes in drug-resistant microorganisms in sandy soil fertilized with selected sewage sludge. Sewage sludge after different types of drying process (natural and solar) was added to the degraded sandy soil. The effect of the methods of sewage sludge drying on concentration of drug-resistant microorganisms in soil fertilized with the sludge was analysed. The study demonstrated that sewage sludge dried naturally in drying beds pose threat to soil environment and, potentially, to people and animals which have contact with fertilized soils. In sandy soils fertilized with these types of sewage sludge, pathogenic forms which exhibit resistance to first-line antibiotics can be found.
Changes in biochemical activity of podzolic soil under willow culture in the second year of treatment with municipal-industrial sewage sludge
J. Furczak,J. Joniec
International Agrophysics , 2007,
Abstract: The objective of the study was to investigate the effect of various doses of municipal-industrial sewage sludge (1, 2.5, 5, 10, and 20%) on selected biochemical parameters of a podzolic soil under willow culture in the second year of the experiment. The effect of the sediment was observable both in the surface horizon and in deeper layers of the soil, though only in the case of some of the tests (cellulose mineralization, nitrification) it was somewhat more pronounced in the Ap horizon. The recorded changes usually intensified with increasing doses of the treatment. The study showed a stimulating effect in the soil of all applied doses of sludge on respiration, cellulose mineralization rate, nitrification and proteolytic activity, and of the higher doses - on dehydrogenases activity. In the case of ammonification, on the other hand, an inhibiting effect of the sludge was observed in almost all of the treatment objects. The observed effect of the sludge on most of the analysed biochemical parameters was relatively consistent in both the surface horizon (0-20 cm) and in the deeper layers of the soil (20-40 cm). Only the processes of cellulose mineralization (in treatment objects with higher doses of sludge) and those of nitrification were subject to stronger stimulation in the Ap horizon. Positive correlations were recorded between almost all of the analysed biochemical tests. An exception was ammonification which showed no correlation with cellulose mineralization and dehydrogenases activity, and negative correlations with the remaining parameters.
Organic carbon dynamics and enzyme activities in agricultural soils amended with biogas slurry, liquid manure and sewage sludge  [PDF]
Britta Stumpe, Steffen Werner, Robert Jung, Stefanie Heinze, Elisabeth Jüschke, Christian Strippel, Bernd Marschner
Agricultural Sciences (AS) , 2012, DOI: 10.4236/as.2012.31014
Abstract: The application of organic soil amendments is a common practice for increasing soil fertility and soil organic carbon (SOC) content. In recent years, a new product from biogas production, biogas slurry is increasingly applied to agricultural soils, although little is known about its effects on soil properties. In this study, the influence of this new product in comparison with liquid manure and sewage sludge on the organic carbon dynamics and enzyme activities were investigated in two different agricultural soils in short-term incubation studies. As a control, biologically inert sand was also amended with these organic wastes. In sand, biogas slurry degraded to 10.4% within 14 days, while no differences were found between the degradability of liquid manure and sewage sludge with 6.6% and 5.4%, respectively. However, although the degradability of biogas slurry was highest among the organic amendments, liquid manure application resulted in the highest respiration rates in the soil samples. This was likely due to the organic waste borne easily decomposable substrates which were most dominant in liquid manure. Organic waste applications were found to generally increase the activity of numerous enzymes but did not change the soil enzyme patterns. Thus, in general it was shown that the microbial population of the organic wastes will not become prominent when introduced with the manures to soils. Thus, an inoculation with organic waste borne microorganisms could likely be neglected when discussing the extent of organic carbon dynamics after organic waste application to agricultural soils.
Forms of Heavy Metals in Sewage Sludge and Soil Amended with Sludge  [PDF]
J. Nouri,B. J. Alloway,P.J. Peterson
Pakistan Journal of Biological Sciences , 2001,
Abstract: A number of extractions were carried out on soils, in order to assess both the relative concentrations of metals available to plants and also the major forms in which these metals existed in soils. The objective of this study was to assess the quantity and forms of metals in different soils, sludge and soils amended with sludge. It seemed that initially each metal will respond differently after incorporation into the soil system. There was a greater fraction of soluble metals in the sludge amended soils than the controls. Micro-organisms might, by using organic and inorganic matter as source of carbon and energy, bring about oxidation and reduction sufficient to change the state of metals.
Heavy metals extractability in a soil amended with sewage sludge
Marchi, Giuliano;Guilherme, Luiz Roberto Guimar?es;Chang, Andrew C.;Nascimento, Clístenes Williams Araújo do;
Scientia Agricola , 2009, DOI: 10.1590/S0103-90162009000500009
Abstract: few investigations have been carried out about the comparison of desorption rate and amount of heavy metals extracted successively by organic acid mixtures mimicking the rhizosphere and routine extractants in sewage sludge-amended soils. extractions of zn, cd, ni, cr, and cu were performed in samples of a sewage sludge-amended soil using seven extractants: four organic acid mixtures and three routine extractants (dtpa, mehlich-i, and ammonium acetate). results from single pass extractions, in which the extractable metal contents were determined by simply extracting the soil a single time, as well as from 15 successive extractions, in which the solid residues of the first extraction was successively extracted 14 additional times, of heavy metals were analyzed. the extractability of heavy metals in a single pass extraction was, in general, as follows: mehlich-i > dtpa > organic acids > nh4oac. the highest rates of extraction followed the general order: dtpa > mehlich-i > organic acids > nh4oac. while mehlich-i presented the highest extractability of heavy metals among studied extractants, dtpa showed a high extractability of zn, cd, ni, and cu in a single extraction as well as the highest rates of extraction among the studied extractants. the transfer of heavy metals from soil to organic acid solutions is slower than to dtpa and mehlich-i extractants.
Effect of wheat (Triticum aestivum L.) rhizosphere on fractionations of copper in some sewage sludge amended soils  [cached]
Motaghian H. R.,Hosseinpur A. R.
E3S Web of Conferences , 2013, DOI: 10.1051/e3sconf/20130104009
Abstract: Our purpose was to quantify the effect of rhizosphere processes on the fractions of Copper (Cu) in 10 soils amended with sewage sludge under greenhouse conditions by using a rhizobox. For amended soils, 1% (w/w) of sewage sludge was added to soil samples and then amended soils were incubated at field capacity, for 1 month. After incubation, soils were put in rhizobox and seeds of wheat were planted. Plants were harvested after 8 weeks and rhizosphere and bulk soils were separated. Fractions of Cu in the rhizosphere and bulk soils were determined. The results showed that Cu extracted using several extractants in rhizospheric soils were significantly (P<0.01) lower than in bulk soils. In the rhizosphere of amended soils the average of residual Cu, Cu associated with iron-manganese oxides, Cu associated with organic matter, Cu associated with carbonates and exchangeable Cu were 18.8, 2.10, 1.00, 0.37 and 0.24 mg kg 1 respectively, whereas above fractions in the bulk soils were 18.1, 2.43, 0.80, 0.42 and 0.30 mg kg 1 respectively. This study illustrated that Cu-fractions in the wheat rhizosphere were different compare to bulk soils in sewage sludge amended soils.
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