Co-digestion of agricultural and municipal waste to produce energy and soil amendment.

PubMed

Macias-Corral, Maritza A; Samani, Zohrab A; Hanson, Adrian T; Funk, Paul A

2017-09-01

In agriculture, manure and cotton gin waste are major environmental liabilities. Likewise, grass is an important organic component of municipal waste. These wastes were combined and used as substrates in a two-phase, pilot-scale anaerobic digester to evaluate the potential for biogas (methane) production, waste minimisation, and the digestate value as soil amendment. The anaerobic digestion process did not show signs of inhibition. Biogas production increased during the first 2 weeks of operation, when chemical oxygen demand and volatile fatty acid concentrations and the organic loading rate to the system were high. Chemical oxygen demand from the anaerobic columns remained relatively steady after the first week of operation, even at high organic loading rates. The experiment lasted about 1 month and produced 96.5 m 3 of biogas (68 m 3 of CH 4 ) per tonne of waste. In terms of chemical oxygen demand to methane conversion efficiency, the system generated 62% of the theoretical methane production; the chemical oxygen demand/volatile solids degradation rate was 62%, compared with the theoretical 66%. The results showed that co-digestion and subsequent digestate composting resulted in about 60% and 75% mass and volume reductions, respectively. Digestate analysis showed that it can be used as a high nutrient content soil amendment. The digestate met Class A faecal coliform standards (highest quality) established in the United States for biosolids. Digestion and subsequent composting concentrated the digestate nitrogen, phosphorus, and potassium content by 37%, 24%, and 317%, respectively. Multi-substrate co-digestion is a practical alternative for agricultural waste management, minimisation of landfill disposal, and it also results in the production of valuable products.

Arsenic adsorption and plant availability in an agricultural soil irrigated with As-rich water: Effects of Fe-rich amendments and organic and inorganic fertilisers.

PubMed

Arco-Lázaro, Elena; Pardo, Tania; Clemente, Rafael; Bernal, Ma Pilar

2018-03-01

The use of As-rich water for irrigation in agricultural soils may result in As accumulation in soil and crops, with the consequent risk of its entry into the food chain. The effectiveness of three different Fe-based materials (a commercial iron oxide (Bayoxide ® ), lamination slag (a by-product of the hot rolling of steel) and a commercial red mud derivative (ViroBind™)) used as soil amendments to minimise the impact of irrigation with As-rich water in an agricultural soil-plant system was evaluated in a pot experiment. Simultaneously, the influence of organic and inorganic fertilisation (olive oil mill waste compost versus NPK fertiliser) on the effectiveness of iron oxide in As adsorption processes was also assessed. The As adsorption capacity of the amendments was determined in a preliminary batch experiment using sorption isotherms. Then, a pot experiment was carried out in a growth chamber using an agricultural soil (arenosol) from Segovia province (central Spain), amended with the different materials, in which Lactuca sativa (lettuce) was grown for two months. The As adsorption capacity was higher in the commercial iron oxide and in the red mud derivative, which fitted the Freundlich model (no saturation), than in the lamination slag, which fitted the Langmuir model (limited adsorption). All the materials decreased the pore water As concentration compared to the control (by 29-80%), but only iron oxide reduced As availability in the soil, and none of the amendments decreased the As concentration in plant leaves. The combination of iron oxide and compost did not significantly improve plant growth, but increased nutrients (N, K, Ca, Na and Mg) concentrations and availability in the soil and their concentration in the plants, relative to the other treatments and the control. Therefore, this seems to be a viable option to prevent As leaching and improve the plant nutritional status. Copyright © 2017 Elsevier Ltd. All rights reserved.

N-C isotopic investigation of a zeolite-amended agricultural field

NASA Astrophysics Data System (ADS)

Ferretti, Giacomo; Natali, Claudio; Faccini, Barbara; Di Giuseppe, Dario; Bianchini, Gianluca; Coltorti, Massimo

2016-04-01

In this study, a C and N isotopic investigation in the soil-plant system of the ZeoLIFE project experimental field have been carried out. Since many years, natural and NH4-enriched zeolites have been used as soil amendant in agricultural context in order to reduce N losses, increase NUE (Nitrogen Use Efficiency) and crop yield. Nevertheless up to now there are no studies that, using the stable isotopes approach, highlighted the interaction between zeolites and plants in agricultural systems. The main aims of this study is to verify if natural zeolites amendment can enhance chemical fertilization efficiency and if N transfer from NH4-enriched zeolites to plants really occurs. Plants grown following traditional cultivation methods (with no zeolite addition) and plants grown on soils amended with natural and NH4-enriched zeolites (the latter obtained after mixing with pig-slurry with a very high 15N) were compared for two cultivation cycles (maize and wheat). As widely known, plants grown under conventional farming systems (use of chemical fertilizers as urea) and plants grown under organic farming can be discriminated by the isotopic signatures of plant tissues. For both years the main results of the study reveals that plants grown on plots amended with natural zeolites generally have their nitrogen isotopic signature more similar to that of the chemical fertilizers employed during the cultivation with respect to the plants cultivated in the non-amended plot. This suggests an enhanced N uptake by the plant from this specific N source with respect to the non-amended plot. On the other hand, plants grown on NH4-enriched zeolites registered a higher 15N, approaching the pig-slurry isotopic signature, confirming that this material can constitute an N pool for plants at least for two cultivation cycles. The distinct agricultural practices seem to be reflected in the plant physiology as recorded by the carbon discrimination factor (13C) which generally increases

Effect of the phosphogypsum amendment of saline and agricultural soils on growth, productivity and antioxidant enzyme activities of tomato (Solanum lycopersicum L.).

PubMed

Smaoui-Jardak, Mariem; Kriaa, Walid; Maalej, Mohamed; Zouari, Mohamed; Kamoun, Lotfi; Trabelsi, Wassim; Ben Abdallah, Ferjani; Elloumi, Nada

2017-10-01

The objective of this study was to investigate the effects of phosphogypsum (PG) amendment on the physiochemical proprieties of saline and agricultural soils along with the growth, productivity and antioxidant enzyme activities of tomato plants ( Solanum lycopersicum L.) grown on the amended soils under controlled conditions. Obtained results showed that the amendment of saline soil (H) by PG induced a decrease in pH as well as in electrical conductivity. However, for the non saline soil (MC), there was a decrease in pH associated with an increase in electrical conductivity. For both soils, PG amendment led to an increase in Calcium (Ca) and sodium (Na), and a decrease in potassium (K) in plant tissues. Cadmium (Cd), Zinc (Zn) and Chromium (Cr) contents in different parts of plants increased in proportion with PG concentration in the soils. Apart from Cd, all the analyzed metals in tomato fruit were found to be below the recommended maximum allowable concentration (MAC). Our results showed that PG application, at doses not exceeding 20%, seems to be beneficial for growth, photosynthetic activity and productivity of tomato plants as well as in decreasing salinity of saline soils. In these conditions, the use of PG could be a promising project for the rehabilitation of marginalized and saline ecosystems with either ornamental or non-fruit species. For both soils, a significant accumulation of MDA in shoots was detected, reflecting cell membrane damage especially when the PG amendment reached 20%. Beyond 20 and 40% PG, tomato plants developed an enzymatic antioxidant defense system in response to salinity and heavy metal stress. However, at 80% PG, enzymes activities were significantly inhibited.

Sewage sludge, compost and other representative organic wastes as agricultural soil amendments: Benefits versus limiting factors.

PubMed

Alvarenga, Paula; Mourinha, Clarisse; Farto, Márcia; Santos, Teresa; Palma, Patrícia; Sengo, Joana; Morais, Marie-Christine; Cunha-Queda, Cristina

2015-06-01

Nine different samples of sewage sludges, composts and other representative organic wastes, with potential interest to be used as agricultural soil amendments, were characterized: municipal sewage sludge (SS1 and SS2), agro industrial sludge (AIS), municipal slaughterhouse sludge (MSS), mixed municipal solid waste compost (MMSWC), agricultural wastes compost (AWC), compost produced from agricultural wastes and sewage sludge (AWSSC), pig slurry digestate (PSD) and paper mill wastes (PMW). The characterization was made considering their: (i) physicochemical parameters, (ii) total and bioavailable heavy metals (Cd, Cr, Cu, Ni, Pb, Zn and Hg), (iii) organic contaminants, (iv) pathogenic microorganisms and (v) stability and phytotoxicity indicators. All the sludges, municipal or other, comply with the requirements of the legislation regarding the possibility of their application to agricultural soil (with the exception of SS2, due to its pathogenic microorganisms content), with a content of organic matter and nutrients that make them interesting to be applied to soil. The composts presented, in general, some constraints regarding their application to soil, and their impairment was due to the existence of heavy metal concentrations exceeding the proposed limit of the draft European legislation. As a consequence, with the exception of AWSSC, most compost samples were not able to meet these quality criteria, which are more conservative for compost than for sewage sludge. From the results, the composting of sewage sludge is recommended as a way to turn a less stabilized waste into a material that is no longer classified as a waste and, judging by the results of this work, with lower heavy metal content than the other composted materials, and without sanitation problems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure

USGS Publications Warehouse

Kinney, C.A.; Furlong, E.T.; Kolpin, D.W.; Burkhardt, M.R.; Zaugg, S.D.; Werner, S.L.; Bossio, J.P.; Benotti, M.J.

2008-01-01

Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained a diverse composition of 28 AWIs, reflecting the presence of human-use compounds. The swine manure contained 12 AWIs, and was dominated by biogenic sterols. Soil and earthworm samples were collected in the spring (about 30 days after soil amendment) and fall (140-155 days after soil amendment) at all field sites. Soils from Site 1 contained 21 AWIs and soil from Sites 2 and 3 contained 19 AWIs. The AWI profiles at Sites 2 and 3 generally reflected the relative composition of AWIs present in waste material applied. There were 20 AWIs detected in earthworms from Site 1 (three compounds exceeding concentrations of 1000 ??g/kg), 25 AWIs in earthworms from Site 2 (seven compounds exceeding concentrations of 1000 ??g/kg), and 21 AWIs in earthworms from Site 3 (five compounds exceeding concentrations of 1000 ??g/kg). A number of compounds thatwere present in the earthworm tissue were at concentrations less than reporting levels in the corresponding soil samples. The AWIs detected in earthworm tissue from the three field sites included pharmaceuticals, synthetic fragrances, detergent metabolites, polycyclic aromatic hydrocarbons (PAHs), biogenic sterols, disinfectants, and pesticides, reflecting a wide range of physicochemical properties. For those contaminants detected in earthworm tissue and soil, bioaccumulation factors

Nitrous oxide emission reduction in temperate biochar-amended soils

NASA Astrophysics Data System (ADS)

Felber, R.; Hüppi, R.; Leifeld, J.; Neftel, A.

2012-01-01

Biochar, a pyrolysis product of organic residues, is an amendment for agricultural soils to improve soil fertility, sequester CO2 and reduce greenhouse gas (GHG) emissions. In highly weathered tropical soils laboratory incubations of soil-biochar mixtures revealed substantial reductions for nitrous oxide (N2O) and carbon dioxide (CO2). In contrast, evidence is scarce for temperate soils. In a three-factorial laboratory incubation experiment two different temperate agricultural soils were amended with green waste and coffee grounds biochar. N2O and CO2 emissions were measured at the beginning and end of a three month incubation. The experiments were conducted under three different conditions (no additional nutrients, glucose addition, and nitrate and glucose addition) representing different field conditions. We found mean N2O emission reductions of 60 % compared to soils without addition of biochar. The reduction depended on biochar type and soil type as well as on the age of the samples. CO2 emissions were slightly reduced, too. NO3- but not NH4+ concentrations were significantly reduced shortly after biochar incorporation. Despite the highly significant suppression of N2O emissions biochar effects should not be transferred one-to-one to field conditions but need to be tested accordingly.

Soil contamination with cadmium, consequences and remediation using organic amendments.

PubMed

Khan, Muhammad Amjad; Khan, Sardar; Khan, Anwarzeb; Alam, Mehboob

2017-12-01

Cadmium (Cd) contamination of soil and food crops is a ubiquitous environmental problem that has resulted from uncontrolled industrialization, unsustainable urbanization and intensive agricultural practices. Being a toxic element, Cd poses high threats to soil quality, food safety, and human health. Land is the ultimate source of waste disposal and utilization therefore, Cd released from different sources (natural and anthropogenic), eventually reaches soil, and then subsequently bio-accumulates in food crops. The stabilization of Cd in contaminated soil using organic amendments is an environmentally friendly and cost effective technique used for remediation of moderate to high contaminated soil. Globally, substantial amounts of organic waste are generated every day that can be used as a source of nutrients, and also as conditioners to improve soil quality. This review paper focuses on the sources, generation, and use of different organic amendments to remediate Cd contaminated soil, discusses their effects on soil physical and chemical properties, Cd bioavailability, plant uptake, and human health risk. Moreover, it also provides an update of the most relevant findings about the application of organic amendments to remediate Cd contaminated soil and associated mechanisms. Finally, future research needs and directions for the remediation of Cd contaminated soil using organic amendments are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Soil biota response to amendment with biochar as P and K fertilizer

NASA Astrophysics Data System (ADS)

Winding, Anne; Imparato, Valentina; Santos, Susana; Hansen, Veronika; Haugaard-Nielsen, Henrik; Browne, Patrick; Hestbjerg Hansen, Lars; Henning Krogh, Paul; Johansen, Anders

2017-04-01

Thermal gasification converts biomass into a combustible gas at oxygen-poor conditions, the bi-product being biochar which can be used as soil amendment to increase pH, sequester carbon to mitigate climate change, and supply phosphate and potassium to crops; replacing chemical or other alternative organic fertilizers. Amending soil with biochar can support three soil functions: production of food, carbon sequestration, and biodiversity. This was tested in a field experiment with reduced-tillage agricultural management, where the effect of biochar amendment on soil ecosystem services, especially biodiversity and carbon sequestration were studied. The effects on soil microorganisms and fauna (protists and earthworms) were assessed with activity based assays and Next Generation Sequencing (NGS). Crops were alternating oil seed rape and winter wheat, and biochar was added annually for 3 years. The soil was a sandy loam soil with SOM content of ca. 5%. Earthworms and soil were sampled from field plots either left untreated, amended with straw or annually amended with either 6-8 t ha-1 or ca. 1 t ha-1 biochar. Soil was sampled from bulk soil and earthworm drilosphere. Earthworms had a priming effect on protist abundance and basal soil respiration. However, in biochar amended soil the protist abundance decreased in the drilosphere. Culturable bacteria and extracellular enzymatic activities were not significantly affected by earthworms. The abundance of only one earthworm species increased at high compared to low application levels of biochar, while still not differing from controls without biochar. Thus, no harmful effects were detected for earthworms. At the lower biochar amendment, significant changes were observed for the activity of a few selected enzymes related to biochar and also a relative increase in abundance of low abundant microorganisms was seen. At the high doses of biochar the abundance of protists increased compared to control. NGS analysis was more

Seasonal and soil-type dependent emissions of nitrous oxide from irrigated desert soils amended with digested poultry manures.

PubMed

Posmanik, Roy; Nejidat, Ali; Dahan, Ofer; Gross, Amit

2017-09-01

Expansion of dryland agriculture requires intensive supplement of organic fertilizers to improve the fertility of nutrient-poor desert soils. The environmental impact of organic supplements in hot desert climates is not well understood. We report on seasonal emissions of nitrous oxide (N 2 O) from sand and loess soils, amended with limed and non-limed anaerobic digestate of poultry manure in the Israeli Negev desert. All amended soils had substantially higher N 2 O emissions, particularly during winter applications, compared to unammended soils. Winter emissions from amended loess (10-175mgN 2 Om -2 day -1 ) were markedly higher than winter emissions from amended sand (2-7mgN 2 Om -2 day -1 ). Enumeration of marker genes for nitrification and denitrification suggested that both have contributed to N 2 O emissions according to prevailing environmental conditions. Lime treatment of digested manure inhibited N 2 O emissions regardless of season or soil type, thus reducing the environmental impact of amending desert soils with manure digestate. Copyright © 2017 Elsevier B.V. All rights reserved.

[Impact of biochar amendment on the sorption and dissipation of chlorantraniliprole in soils].

PubMed

Wang, Ting-Ting; Yu, Xiang-Yang; Shen, Yaen; Zhang, Chao-Lan; Liu, Xian-Jin

2012-04-01

The effects of biochar amendment on sorption and dissipation of chlorantraniliprole (CAP) in 5 different agricultural soils were studied. Red gum wood (Eucalyptus spp.) derived biochar was amended into a black soil, a yellow soil, a red soil, a purplish soil, and a fluvo-aquic soil at the rate of 0.5% (by weight). The sorption and dissipation behaviors of CAP in soils with and without biochar amendment were measured by batch equilibration technique and dissipation kinetic experiment, respectively. The objective was to investigate the impact of biochar application on the environmental fate of pesticides in agricultural soils with different physical-chemical properties, and evaluate the potential ecological impacts of field application of biochar materials. The results showed that biochar application in soils could enhance the sorption of CAP, but the magnitudes were varied among soils with different properties. Amendment of 0.5% (by weight) biochar in the black soil, which have high content of organic matter (4.59%), resulted in an increase of sorption coefficient (K(d)) by 2.17%; while for the fluvo-aquic soil with organic matter content of 1.16%, amendment of biochar at the same level led to an increase of 139.13%. The sorption capacity of biochar was partially suppressed when biochar was mixed with soils. The calculated K(Fbiochar) of biochar after mixed in the black soil, yellow soil, red soil, purplish soil, and fluvo-aquic soil were decreased by 96.94%, 90.6%, 91.31%, 68.26%, and 34.59%, respectively, compared to that of the original biochar. The half-lives of CAP in black soil, yellow soil, red soil, purplish soil, and fluvo-aquic soil were 115.52, 133.30, 154.03, 144.41 and 169.06 d, respectively. In soils amended with biochar, the corresponding half-lives of CAP were extended by 20.39, 35.76, 38.51, 79.19, and 119.75 d, respectively. Similar to the effects of biochar on CAP sorption, in soil with higher content of organic matter, the retardation of CAP

Stability of immobilization remediation of several amendments on cadmium contaminated soils as affected by simulated soil acidification.

PubMed

Guo, Fuyu; Ding, Changfeng; Zhou, Zhigao; Huang, Gaoxiang; Wang, Xingxiang

2018-06-04

Chemical immobilization is a practical approach to remediate heavy metal contamination in agricultural soils. However, the potential remobilization risks of immobilized metals are a major environmental concern, especially in acid rain zones. In the present study, changes in the immobilization efficiency of several amendments as affected by simulated soil acidification were investigated to evaluate the immobilization remediation stability of several amendments on two cadmium (Cd) contaminated soils. Amendments (hydrated lime, hydroxyapatite and biochar) effectively immobilized Cd, except for organic fertilizer, and their immobilizations were strongly decreased by the simulated soil acidification. The ratio of changes in CaCl 2 -extractable Cd: pH (△CaCl 2 -Cd/△pH) can represent the Cd remobilization risk of different amended soils. Hydroxyapatite and biochar had a stronger durable immobilizing effect than did hydrated lime, particularly in soil with a lower pH buffering capacity, which was further confirmed by the Cd concentration and accumulation in lettuce. These results can be attributed to that hydroxyapatite and biochar transformed greater proportions of exchangeable Cd to other more stable fractions than lime. After 48 weeks of incubation, in soil with a lower pH buffering capacity, the immobilization efficiencies of lime, hydroxyapatite, biochar and organic fertilizer in the deionized water group (pH 6.5) were 71.7%, 52.7%, 38.6% and 23.9%, respectively, and changed to 19.1%, 33.6%, 26.5% and 5.0%, respectively, in the simulated acid rain group (pH 2.5). The present study provides a simple method to preliminarily estimate the immobilization efficiency of amendments and predict their stability in acid rain regions before large-scale field application. In addition, hydrated lime is recommended to be combined with other acid-stable amendments (such as hydroxyapatite or biochar) to remediate heavy metal-contaminated agricultural soils in acid precipitation

Effect of biochar amendment on tylosin adsorption-desorption and transport in two different soils

Treesearch

Chang Yoon Jeong; Jim J. Wang; Syam K. Dodla; Thomas L. Eberhardt; Les Groom

2012-01-01

The role of biochar as a soil amendment on the adsorption¨C desorption and transport of tylosin, a macrolide class of veterinary antibiotic, is little known. In this study, batch and column experiments were conducted to investigate the adsorption kinetics and transport of tylosin in forest and agricultural corn field soils amended with hardwood and softwood biochars....

Unexpected stimulation of soil methane uptake as emergent property of agricultural soils following bio-based residue application.

PubMed

Ho, Adrian; Reim, Andreas; Kim, Sang Yoon; Meima-Franke, Marion; Termorshuizen, Aad; de Boer, Wietse; van der Putten, Wim H; Bodelier, Paul L E

2015-10-01

Intensification of agriculture to meet the global food, feed, and bioenergy demand entail increasing re-investment of carbon compounds (residues) into agro-systems to prevent decline of soil quality and fertility. However, agricultural intensification decreases soil methane uptake, reducing, and even causing the loss of the methane sink function. In contrast to wetland agricultural soils (rice paddies), the methanotrophic potential in well-aerated agricultural soils have received little attention, presumably due to the anticipated low or negligible methane uptake capacity in these soils. Consequently, a detailed study verifying or refuting this assumption is still lacking. Exemplifying a typical agricultural practice, we determined the impact of bio-based residue application on soil methane flux, and determined the methanotrophic potential, including a qualitative (diagnostic microarray) and quantitative (group-specific qPCR assays) analysis of the methanotrophic community after residue amendments over 2 months. Unexpectedly, after amendments with specific residues, we detected a significant transient stimulation of methane uptake confirmed by both the methane flux measurements and methane oxidation assay. This stimulation was apparently a result of induced cell-specific activity, rather than growth of the methanotroph population. Although transient, the heightened methane uptake offsets up to 16% of total gaseous CO2 emitted during the incubation. The methanotrophic community, predominantly comprised of Methylosinus may facilitate methane oxidation in the agricultural soils. While agricultural soils are generally regarded as a net methane source or a relatively weak methane sink, our results show that methane oxidation rate can be stimulated, leading to higher soil methane uptake. Hence, even if agriculture exerts an adverse impact on soil methane uptake, implementing carefully designed management strategies (e.g. repeated application of specific residues) may

Biochar has no effect on soil respiration across Chinese agricultural soils.

PubMed

Liu, Xiaoyu; Zheng, Jufeng; Zhang, Dengxiao; Cheng, Kun; Zhou, Huimin; Zhang, Afeng; Li, Lianqing; Joseph, Stephen; Smith, Pete; Crowley, David; Kuzyakov, Yakov; Pan, Genxing

2016-06-01

Biochar addition to soil has been widely accepted as an option to enhance soil carbon sequestration by introducing recalcitrant organic matter. However, it remains unclear whether biochar will negate the net carbon accumulation by increasing carbon loss through CO2 efflux from soil (soil respiration). The objectives of this study were to address: 1) whether biochar addition increases soil respiration; and whether biochar application rate and biochar type (feedstock and pyrolyzing system) affect soil respiration. Two series of field experiments were carried out at 8 sites representing the main crop production areas in China. In experiment 1, a single type of wheat straw biochar was amended at rates of 0, 20 and 40 tha(-1) in four rice paddies and three dry croplands. In experiment 2, four types of biochar (varying in feedstock and pyrolyzing system) were amended at rates of 0 and 20 tha(-1) in a rice paddy under rice-wheat rotation. Results showed that biochar addition had no effect on CO2 efflux from soils consistently across sites, although it increased topsoil organic carbon stock by 38% on average. Meanwhile, CO2 efflux from soils amended with 40 t of biochar did not significantly higher than soils amended with 20 t of biochar. While the biochars used in Experiment 2 had different carbon pools and physico-chemical properties, they had no effect on soil CO2 efflux. The soil CO2 efflux following biochar addition could be hardly explained by the changes in soil physic-chemical properties and in soil microbial biomass. Thus, we argue that biochar will not negate the net carbon accumulation by increasing carbon loss through CO2 efflux in agricultural soils. Copyright © 2016. Published by Elsevier B.V.

Short-term changes of metal availability in soil. Part I: comparing sludge-amended with metal-spiked soils.

PubMed

Natal-da-Luz, T; Ojeda, G; Costa, M; Pratas, J; Lanno, R P; Van Gestel, C A M; Sousa, J P

2012-08-01

Sewage sludge application to soils is regulated by its total metal content. However, the real risk of metals is determined by the fraction that is biologically available. The available fraction is highly related to the strength of metal binding by the matrix, which is a dynamic process. The evaluation of the fate of metals in time can contribute increased accuracy of ecological risk assessment. Aiming to evaluate short-term changes in metal availability when metals were applied to soil directly (metal-spiked) or by way of an organic matrix (sludge-amended), a laboratory experiment was performed using open microcosms filled with agricultural soil. A concentration gradient of industrial sludge (11, 15, 55, and 75 t/ha) that was contaminated predominantly with chromium, copper, nickel, and zinc, or soil freshly spiked with the same concentrations of these metals, were applied on top of the agricultural soil. After 0, 3, 6, and 12 weeks, total (HNO(3) 69 %) and 0.01 M CaCl(2)-extractable metal concentrations in soil and metal content in the percolates were measured. Results demonstrated that comparison between sludge-amended and metal-spiked soils may give important information about the role of sludge matrix on metal mobility and availability in soil. In sludge-amended soils, extractable-metal concentrations were independent of the sludge concentration and did not change over time. In metal-spiked soils, metal extractability decreased with time due to ageing and transport of metals to deeper layers. In general, the sludge matrix increased the adsorption of metals, thus decreasing their mobility in soils.

Single application of Sewage Sludge to an Alluvial Agricultural Soil - impacts on Soil Quality

NASA Astrophysics Data System (ADS)

Suhadolc, M.; Graham, D. B.; Hagn, A.; Doerfler, U.; Schloter, M.; Schroll, R.; Munch, J. C.; Lobnik, F.

2009-04-01

Limited information exists on the effects of sewage sludge on soil quality with regard to their ability to maintain soil functions. We studied effects of sewage sludge amendment on soil chemical properties, microbial community structure and microbial degradation of the herbicide glyphosate. Three months soil column leaching experiment has been conducted using alluvial soils (Eutric Fluvisol) with no prior history of sludge application. The soil was loamy with pH 7,4 and organic matter content of 3,5%. Soil material in the upper 2 cm of columns was mixed with dehydrated sewage sludge which was applied in amounts corresponding to the standards governing the use of sewage sludge for agricultural land. Sludge did increase some nutrients (total N, NH4+, available P and K, organic carbon) and some heavy metals contents (Zn, Cu, Pb) in soil. However, upper limits for heavy metals in agricultural soils were not exceeded. Results of heavy metal availability in soil determined by sequential extraction will be also presented. Restriction fragment length polymorphism (RFLP) analyses of 16s/18s rDNA, using universal fungal and bacterial primers, revealed clear shifts in bacterial and fungal community structure in the upper 2 cm of soils after amendment. Fungal fingerprints showed greater short term effects of sewage sludge, whereas sewage sludge seems to have prolonged effects on soil bacteria. Furthermore, sewage sludge amendment significantly increased glyphosate degradation from 21.6±1% to 33.6±1% over a 2 months period. The most probable reasons for shifts in microbial community structure and increased degradation of glyphosate are beneficial alterations to the physical-chemical characteristics of the soil. Negative effects of potentially toxic substances present in the sewage sludge on soil microbial community functioning were not observed with the methods used in our study.

Soil microbial properties after 5 years of consecutive amendment with composted tannery sludge.

PubMed

Araujo, Ademir Sérgio Ferreira; Miranda, Ana Roberta Lima; Oliveira, Mara Lucia Jacinto; Santos, Vilma Maria; Nunes, Luís Alfredo Pinheiro Leal; Melo, Wanderley José

2015-01-01

Composting has been recognised an alternative method to tannery sludge recycling and afterwards to be used in agriculture. As the tannery sludge contains salts and chromium, the application of composted tannery sludge (CTS) should be performed carefully to minimise negative effects on soil microbial properties. Therefore, this study evaluated the effects of 5-year repeated CTS amendment on soil microbial biomass (SMB) and enzyme activities in a tropical soil. CTS was applied during 5 years at 0, 2.5, 5, 10 and 20 Mg ha(-1), and at the fifth year, the microbial biomass C (MBC) and N (MBN), basal and substrate-induced respiration (SIR), metabolic quotient (qCO₂) and dehydrogenase (DHA) and fluorescein diacetate (FDA) hydrolysis were determined in the soil samples. Soil MBC and MBN showed the highest values with the amendment of 5 Mg ha(-1) CTS. Soil respiration increased with the increase in CTS rates, while SIR showed the highest values with the amendment of 0, 2.5 and 5 Mg ha(-1) CTS. DHA activity showed the highest values with the amendment up to 2.5 Mg ha(-1), while FDA hydrolysis increased up to the rate of 5 Mg ha(-1) CTS. The results show that after 5 years of permanent amendment of CTS, soils amended with 2.5 Mg ha(-1) have SMB and enzymatic activities similar to those in unamended soil.

Phosphorus leaching from soils amended with thermally gasified piggery waste ash.

PubMed

Kuligowski, Ksawery; Poulsen, Tjalfe Gorm

2009-09-01

In regions with intensive livestock farming, thermal treatment for local energy extraction from the manure and export of the P rich ash as a fertilizer has gained interest. One of the main risks associated with P fertilizers is eutrophication of water bodies. In this study P and K mobility in ash from anaerobically digested, thermally gasified (GA) and incinerated (IA) piggery waste has been tested using water loads ranging from 0.1 to 200 ml g(-1). Leaching of P from soil columns amended with GA was investigated for one P application rate (205 kg P ha(-1) corresponding to 91 mg P kg(-1) soil dry matter) as a function of precipitation rate (9.5 and 2.5 mm h(-1)), soil type (Jyndevad agricultural soil and sand), amount of time elapsed between ash amendment and onset of precipitation (0 and 5 weeks) and compared to leaching from soils amended with a commercial fertilizer (Na(2)HPO(4)). Water soluble P in GA and IA constituted 0.04% and 0.8% of total ash P. Ash amended soil released much less P (0.35% of total P applied in sand) than Na(2)HPO(4) (97% and 12% of total P applied in Jyndevad and sand, respectively).

A proposed NRCS conservation practice standard: Amending soil properties with gypsiferous products

USDA-ARS?s Scientific Manuscript database

This paper will discuss the proposed new NRCS conservation practice standard regarding the use of gypsiferous products in agriculture. Gypsiferous products include gypsum (CaSO4 .2H2O), has been used as an agricultural soil amendment for over 250 years as a soluble source of calcium and sulfur for ...

Environmental fate of the fungicide metalaxyl in soil amended with composted olive-mill waste and its biochar: An enantioselective study.

PubMed

Gámiz, Beatriz; Pignatello, Joseph J; Cox, Lucía; Hermosín, María C; Celis, Rafael

2016-01-15

A large number of pesticides are chiral and reach the environment as mixtures of optical isomers or enantiomers. Agricultural practices can affect differently the environmental fate of the individual enantiomers. We investigated how amending an agricultural soil with composted olive-mill waste (OMWc) or its biochar (BC) at 2% (w:w) affected the sorption, degradation, and leaching of each of the two enantiomers of the chiral fungicide metalaxyl. Sorption of metalaxyl enantiomers was higher on BC (Kd ≈ 145 L kg(-1)) than on OMWc (Kd ≈ 22 L kg(-1)) and was not enantioselective in either case, and followed the order BC-amended>OMWc-amended>unamended soil. Both enantiomers showed greater resistance to desorption from BC-amended soil compared to unamended and OMWc-amended soil. Dissipation studies revealed that the degradation of metalaxyl was more enantioselective (R>S) in unamended and OMWc-amended soil than in BC-amended soil. The leaching of both S- and R-metalaxyl from soil columns was almost completely suppressed after amending the soil with BC and metalaxyl residues remaining in the soil columns were more racemic than those in soil column leachates. Our findings show that addition of BC affected the final enantioselective behavior of metalaxyl in soil indirectly by reducing its bioavailability through sorption, and to a greater extent than OMWc. BC showed high sorption capacity to remove metalaxyl enantiomers from water, immobilize metalaxyl enantiomers in soil, and mitigate the groundwater contamination problems particularly associated with the high leaching potential of the more persistent enantiomer. Copyright © 2015 Elsevier B.V. All rights reserved.

Short-term effects of different organic amendments on soil chemical, biochemical and biological indicators

NASA Astrophysics Data System (ADS)

Mondelli, Donato; Aly, Adel; Yirga Dagnachew, Ababu; Piscitelli, Lea; Dumontet, Stefano; Miano, Teodoro

2014-05-01

The limited availability of animal manure and the high cost of good quality compost lead to difficult soil quality management under organic agriculture. Therefore, it is important to find out alternative organic soil amendments and more flexible strategies that are able to sustain crop productivity and maintain and enhance soil quality. A three years study was carried out in the experimental fields of the Mediterranean Agronomic Institute of Bari located in Valenzano, Italy. The main objective of this research is to investigate the effects of different fertility management strategies on soil quality in order to estimate the role of innovative matrices for their use in organic farming. The experiment consists of seven treatments applied to a common crop rotation. The treatments include alternative organic amendments (1- olive mill wastewater OMW, 2- residues of mushroom cultivation MUS, 3- coffee chaff COF), common soil amendments (4- compost COM, 5- faba bean intercropping LEG, 6- cow manure - MAN) and as a reference treatment (7- mineral fertilizer COV). The soil quality was assessed before and after the application of the treatments, through biological (microbial biomass carbon and nitrogen, soil respiration and metabolic quotient), biochemical (soil enzymatic activities: β-glucosidase, alkaline phospatase, urease, fluorescein diacetate (FDA) hydrolysis), and chemical (pH, soil organic carbon, soil organic matter, total nitrogen, available phosphorous, exchangeable potassium, dissolved organic carbon and total dissolved nitrogen) indicators. Based on the results obtained after the second year, all treatments were able to improve various soil chemical parameters as compared to mineral fertilizer. The incorporation of COF and OMW seemed to be more effective in improving soil total N and exchangeable K, while MAN significantly increased available P. All the amendments enhance dissolved organic C, soil respiration, microbial biomass and metabolic quotient as

Nitrous Oxide Emission and Denitrifier Abundance in Two Agricultural Soils Amended with Crop Residues and Urea in the North China Plain.

PubMed

Gao, Jianmin; Xie, Yingxin; Jin, Haiyang; Liu, Yuan; Bai, Xueying; Ma, Dongyun; Zhu, Yunji; Wang, Chenyang; Guo, Tiancai

2016-01-01

The application of crop residues combined with Nitrogen (N) fertilizer has been broadly adopted in China. Crop residue amendments can provide readily available C and N, as well as other nutrients to agricultural soils, but also intensify the N fixation, further affecting N2O emissions. N2O pulses are obviously driven by rainfall, irrigation and fertilization. Fertilization before rainfall or followed by flooding irrigation is a general management practice for a wheat-maize rotation in the North China Plain. Yet, little is known on the impacts of crop residues combined with N fertilizer application on N2O emission under high soil moisture content. A laboratory incubation experiment was conducted to investigate the effects of two crop residue amendments (maize and wheat), individually or in combination with N fertilizer, on N2O emissions and denitrifier abundance in two main agricultural soils (one is an alluvial soil, pH 8.55, belongs to Ochri-Aquic Cambosols, OAC, the other is a lime concretion black soil, pH 6.61, belongs to Hapli-Aquic Vertosols, HAV) under 80% WFPS (the water filled pore space) in the North China Plain. Each type soil contains seven treatments: a control with no N fertilizer application (CK, N0), 200 kg N ha-1 (N200), 250 kg N ha-1 (N250), maize residue plus N200 (MN200), maize residue plus N250 (MN250), wheat residue plus N200 (WN200) and wheat residue plus N250 (WN250). Results showed that, in the HAV soil, MN250 and WN250 increased the cumulative N2O emissions by 60% and 30% compared with N250 treatment, respectively, but MN200 and WN200 decreased the cumulative N2O emissions by 20% and 50% compared with N200. In the OAC soil, compared with N200 or N250, WN200 and WN250 increased the cumulative N2O emission by 40%-50%, but MN200 and MN250 decreased the cumulative N2O emission by 10%-20%. Compared with CK, addition of crop residue or N fertilizer resulted in significant increases in N2O emissions in both soils. The cumulative N2O emissions

Phenylurea herbicide sorption to biochars and agricultural soil

PubMed Central

WANG, DAOYUAN; MUKOME, FUNGAI N. D.; YAN, DENGHUA; WANG, HAO; SCOW, KATE M.; PARIKH, SANJAI J.

2016-01-01

Biochar is increasingly been used as a soil amendment to improve water holding capacity, reduce nutrient leaching, increase soil pH and also as a means to reduce contamination through sorption of heavy metals or organic pollutants. The sorption behavior of three phenylurea herbicides (monuron, diuron, linuron) on five biochars (Enhanced Biochar, Hog Waste, Turkey Litter, Walnut Shell and Wood Feedstock) and an agricultural soil (Yolo silt loam) was investigated using a batch equilibration method. Sorption isotherms of herbicides to biochars were well described by the Freundlich model (R2 = 0.93 -- 0.97). The adsorption KF values ranged from 6.94 to 1306.95 mg kg−1 and indicated the sorption of herbicides in the biochars and Yolo soil was in the sequence of linuron > diuron > monuron and walnut shell biochar > wood feedstock biochar > turkey litter biochar > enhanced biochar > hog waste biochar > Yolo soil. These data show that sorption of herbicides to biochar can have both positive (reduced off-site transport) and negative (reduced herbicide efficacy) implications and specific biochar properties, such as H/C ratio and surface area, should be considered together with soil type, agriculture chemical and climate condition in biochar application to agricultural soil to optimize the system for both agricultural and environmental benefits. PMID:26065514

Terra Pretas: Charcoal Amendments Influence on Relict Soils and Modern Agriculture

ERIC Educational Resources Information Center

Ricigliano, Kristin

2011-01-01

Most soils found in the Amazon region are characterized by highly weathered profiles that are incapable of longterm agricultural production. However, small patches of highly fertile relict soil referred to as Terra Pretas, are also found in the Amazon region, and have maintained their integrity for thousands of years. These soils were…

Fate and effect of imidacloprid on vermicompost-amended soils under dissimilar conditions: Risk for soil functions, structure, and bacterial abundance.

PubMed

Castillo Diaz, Jean Manuel; Martin-Laurent, Fabrice; Beguet, Jérèmie; Nogales, Rogelio; Romero, Esperanza

2017-02-01

The fate and impact of pesticide on soil depend partly on the agricultural practices, such as prior treatment with pesticide and/or organic amendments. As a means of determining how the previous soil conditions can affect the fate of imidacloprid (IMI) and its effect on soil functions, experiments were made with soil samples, double-amended or not with either vine-shoot (W) or olive cake (O) vermicompost or contaminated or not with IMI. These soil samples, incubated for 3months, were placed in two microcosms (M1 with the pre-amended soils and M2 with the pre-exposed soils), treated with IMI and amended with vermicomposts and then incubated for 3months. The IMI distribution on soil fractions, sorption processes, dissipation kinetics, and biochemical as well as genetic structure and bacterial abundance were determined to assess the fate and impact of IMI on the soil. The addition of W vermicompost to the soil reduced the IMI availability. The dissipation kinetic in soils from M1 and M2 followed, respectively, a single first-order and a double first-order in parallel models. The lowest IMI persistence corresponded to the soil from M2 amended with O-vermicompost with DT50 and DT90 values of 67d and 265d, while in the other soils 90% dissipation required >512d. The vermicomposts-amended contaminated soils increased the dehydrogenase activity by 2- and 4-fold respect the control soils. However, the urease activity decreased due to the IMI influence. The changes in the bacterial community in the contaminated soil amended with O-vermicompost during incubation were correlated with the dissipation rate constant of IMI, suggesting a better tolerance of microorganisms to IMI. Thus, in the soil contaminated with IMI, the amendment with the vermicompost from olive cake can mitigate the impact of this insecticide on soil functions and promote its depuration capability while minimizing environmental risks. Copyright © 2016 Elsevier B.V. All rights reserved.

The enhancement of atrazine sorption and microbial transformation in biochars amended black soils.

PubMed

Yang, Fan; Zhang, Wei; Li, Jinmei; Wang, Shuyao; Tao, Yue; Wang, Yifan; Zhang, Ying

2017-12-01

Generally, biochar plays an important role in controlling migration and accumulation of pollutants in soil. In this dissertation, biochars derived from wheat straws at various pyrolysis temperatures are used to investigate how biochar amendment affects adsorption and microbial degradation of atrazine (typical diffuse herbicide) in soils. In order to explore the influence of soil components, soil samples with different organic matter content are collected from typical agricultural sites, which are characterized as black soils in the northeast region of China. The basic sorption characteristics of biochars from wheat straws prepared at diverse pyrolysis temperature are analyzed, along with the comparisons of the sorption difference in the raw soil and soil amended with biochars at four levels of ratio (0.1%, 0.5%, 1.0% and 2.0%). By incubation experiments, atrazine degradation in non-sterile and sterile soils and effects of atrazine degradation rate after biochar amendment are also studied. Atrazine degradation is significantly enhanced in biochar amended soils, which may be because that biochar supplement can promote the growth and metabolism of microorganisms in the soil. Our findings reveal that wheatstraw- derived biochars may be effective remediation reagents for activating degradation of the soil functional microorganism and enhancing sorption of organic matter content, which can be applied to environmental-friendly accelerate the remediation of atrazine contaminated black soils. Copyright © 2017. Published by Elsevier Ltd.

Organic amendments enhance microbial diversity and abundance of functional genes in Australian Soils

NASA Astrophysics Data System (ADS)

Aldorri, Sind; McMillan, Mary; Pereg, Lily

2016-04-01

Food and cash crops play important roles in Australia's economy with black, grey and red clay soil, widely use for growing cotton, wheat, corn and other crops in rotation. While the majority of cotton growers use nitrogen and phosphate fertilizers only in the form of agrochemicals, a few experiment with the addition of manure or composted plant material before planting. We hypothesized that the use of such organic amendments would enhance the soil microbial function through increased microbial diversity and abundance, thus contribute to improved soil sustainability. To test the hypothesis we collected soil samples from two cotton-growing farms in close geographical proximity and with mostly similar production practices other than one grower has been using composted plants as organic amendment and the second farmer uses only agrochemicals. We applied the Biolog Ecoplate system to study the metabolic signature of microbial communities and used qPCR to estimate the abundance of functional genes in the soil. The soil treated with organic amendments clearly showed higher metabolic activity of a more diverse range of carbon sources as well as higher abundance of genes involved in the nitrogen and phosphorous cycles. Since microbes undertake a large number of soil functions, the use of organic amendments can contribute to the sustainability of agricultural soils.

Elemental transport and distribution in soils amended with incinerated sewage sludge.

PubMed

Paramasivam, S; Sajwan, K S; Alva, A K; VanClief, D; Hostler, K H

2003-05-01

Sewage sludge (SS) is the major solid waste of sewage and wastewater treatment plants in cities around the world. Even though treated effluent water from wastewater treatment plants are utilized for irrigation, disposal of sewage sludge is becoming a serious problem. This is due to its high content of certain heavy metals still posing threat of accumulation in plants and groundwater contamination when it is used as soil amendment or disposed in landfills. Water treatment plants incinerate the dewatered activated sewage sludge (ISS) and dissolve the ash in water to store in ash ponds for long-term storage (WISS). A study was undertaken to evaluate the transport and leaching potential of various elements and their distribution within soil columns amended with various rates of ISS. Results of this study indicates that ISS from wastewater treatment plants can be used as soil amendment on agricultural lands at low to medium rates (< or = 100 Mg ha(-1)) without causing potential loading of metals into groundwater.

Effects of soil amendment on soil characteristics and maize yield in Horqin Sandy Land

NASA Astrophysics Data System (ADS)

Zhou, L.; Liu, J. H.; Zhao, B. P.; Xue, A.; Hao, G. C.

2016-08-01

A 4-year experiment was conducted to investigate the inter-annual effects of sandy soil amendment on maize yield, soil water storage and soil enzymatic activities in sandy soil in Northeast China in 2010 to 2014. We applied the sandy soil amendment in different year, and investigated the different effects of sandy soil amendment in 2014. There were six treatments including: (1) no sandy soil amendment application (CK); (2) one year after applying sandy soil amendment (T1); (3) two years after applying sandy soil amendment(T2); (4) three years after applying sandy soil amendment(T3); (5)four years after applying sandy soil amendment(T4); (6) five years after applying sandy soil amendment (T5). T refers to treatment, and the number refers to the year after application of the sandy soil amendment. Comparing with CK, sandy soil amendments improved the soil water storage, soil urease, invertase, and catalase activity in different growth stages and soil layers, the order of soil water storage in all treatments roughly performed: T3 > T5 > T4 > T2 > T1 > CK. the order of soil urease, invertase, and catalase activity in all treatments roughly performed: T5 > T3 > T4 > T2 > T1 > CK. Soil application of sandy soil amendment significantly (p≤⃒0.05) increased the grain yield and biomass yield by 22.75%-41.42% and 29.92%-45.45% respectively, and maize yield gradually increased with the years go by in the following five years. Sandy soil amendment used in poor sandy soil had a positive effect on soil water storage, soil enzymatic activities and maize yield, after five years applied sandy soil amendment (T5) showed the best effects among all the treatments, and deserves further research.

Mineralization of soil organic matter in biochar amended agricultural landscape

NASA Astrophysics Data System (ADS)

Chintala, R.; Clay, D. E.; Schumacher, T. E.; Kumar, S.; Malo, D. D.

2015-12-01

Pyrogenic biochar materials have been identified as a promising soil amendment to enhance climate resilience, increase soil carbon recalcitrance and achieve sustainable crop production. A three year field study was initiated in 2013 to study the impact of biochar on soil carbon and nitrogen storage on an eroded Maddock soil series - Sandy, Mixed, Frigid Entic Hapludolls) and deposition Brookings clay loam (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) landscape positions. Three biochars produced from corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were incorporated at 9.75 Mg ha-1 rate (≈7.5 cm soil depth and 1.3 g/cm3 soil bulk density) with a rototiller. The changes in chemical fractionation of soil carbon (soluble C, acid hydrolyzable C, total C, and δ13 C) and nitrogen (soluble N, acid hydrolyzable N, total N, and δ14 N) were monitored for two soil depths (0-7.5 and 7.5 - 15 cm). Soluble and acid hydrolyzable fractions of soil C and N were influenced by soil series and were not significantly affected by incorporation of biochars. Based on soil and plant samples to be collected in the fall of 2015, C and N budgets are being developed using isotopic and non-isotopic techniques. Laboratory studies showed that the mean residence time for biochars used in this study ranged from 400 to 666 years. Laboratory and field studies will be compared in the presentation.

Reversible and irreversible sorption of agrochemicals in biochar amended soils: synergistic effects of heavy metals

USDA-ARS?s Scientific Manuscript database

Soil amendment of biochar products from thermochemical waste-to-energy conversion (slow/fast pyrolysis and gasification) of biomass has received considerable interests for both contaminated and agricultural sites. Recalcitrant nature of biochar manifests in their decade-long effectiveness in soil a...

Effects of aging process on adsorption-desorption and bioavailability of fomesafen in an agricultural soil amended with rice hull biochar.

PubMed

Khorram, Mahdi Safaei; Lin, Dunli; Zhang, Qian; Zheng, Yuan; Fang, Hua; Yu, Yunlong

2017-06-01

Biochar has been introduced as an acceptable soil amendment due to its environmental benefits such as sequestering soil contaminants. However, the aging process in biochar amended soil probably decreases the adsorption capacity of biochar through changing its physico-chemical properties. Adsorption, leaching and bioavailability of fomesafen to corn in a Chinese soil amended by rice hull biochar after 0, 30, 90 and 180days were investigated. Results showed that the addition of 0.5%-2% fresh biochar significantly increases the adsorption of fomesafen 4-26 times compare to unamended soil due to higher SSA of biochar. Biochar amendment also decreases fomesafen concentration in soil pore water by 5%-23% resulting lower risk of the herbicide for cultivated plants. However, the aging process decreased the adsorption capacity of biochar since the adsorption coefficient values which was 1.9-12.4 in 0.5%-2% fresh biochar amended soil, declined to 1.36-4.16, 1.13-2.78 and 0.95-2.31 in 1, 3 and 6-month aged treatments, respectively. Consequently, higher desorption, leaching and bioavailable fraction of fomesafen belonged to 6-month aged treatment. Nevertheless, rice hull biochar was effective for sequestering fomesafen as the adsorption capacity of biochar amended soil after 6months of aging was still 2.5-5 times higher compared to that of unamended soil. Copyright © 2016. Published by Elsevier B.V.

Trace element biogeochemistry in the soil-water-plant system of a temperate agricultural soil amended with different biochars.

PubMed

Kloss, Stefanie; Zehetner, Franz; Buecker, Jannis; Oburger, Eva; Wenzel, Walter W; Enders, Akio; Lehmann, Johannes; Soja, Gerhard

2015-03-01

Various biochar (BC) types have been investigated as soil amendment; however, information on their effects on trace element (TE) biogeochemistry in the soil-water-plant system is still scarce. In the present study, we determined aqua-regia (AR) and water-extractable TEs of four BC types (woodchips (WC), wheat straw (WS), vineyard pruning (VP), pyrolyzed at 525 °C, of which VP was also pyrolyzed at 400 °C) and studied their effects on TE concentrations in leachates and mustard (Sinapis alba L.) tissue in a greenhouse pot experiment. We used an acidic, sandy agricultural soil and a BC application rate of 3% (w/w). Our results show that contents and extractability of TEs in the BCs and effectuated changes of TE biogeochemistry in the soil-water-plant system strongly varied among the different BC types. High AR-digestable Cu was found in VP and high B contents in WC. WS had the highest impact on TEs in leachates showing increased concentrations of As, Cd, Mo, and Se, whereas WC application resulted in enhanced leaching of B. All BC types increased Mo and decreased Cu concentrations in the plant tissue; however, they showed diverging effects on Cu in the leachates with decreased concentrations for WC and WS, but increased concentrations for both VPs. Our results demonstrate that BCs may release TEs into the soil-water-plant system. A BC-induced liming effect in acidic soils may lead to decreased plant uptake of cationic TEs, including Pb and Cd, but may enhance the mobility of anionic TEs like Mo and As. We also found that BCs with high salt contents (e.g., straw-based BCs) may lead to increased mobility of both anionic and cationic TEs in the short term.

Short-term effects of natural and NH4+-enriched chabazite zeolitite amendments to soil microbial biomass

NASA Astrophysics Data System (ADS)

Ferretti, Giacomo; Keiblinger, Katharina Maria; Di Giuseppe, Dario; Faccini, Barbara; Colombani, Nicolò; Zechmeister-Boltenstern, Sophie; Coltorti, Massimo; Mastrocicco, Micòl

2017-04-01

Natural zeolite-bearing rocks (zeolitites) are known to be a suitable material for agricultural purposes by improving soil physicochemical properties and nitrogen use efficiency (NUE). However, little is known about their effects on soil microbial biomass. Aim of this work is to evaluate short-term effects of different chabazite-zeolitite amendments on soil microbial biomass (and activity). To this purpose a silty-clay agricultural soil was amended in three different ways, by the addition of 5 and 15 wt% of natural chabazite zeolitites (NZ) and 10 wt% of NH4+-enriched chabazite zeolitites (CZ). Soil pH, water content, dissolved organic carbon (C), total dissolved N, NH4+, NO3-, NO2-, microbial biomass C and N and ergosterol were periodically measured over a time course of 16 days in a laboratory incubation experiment. In order to verify the immobilization of N derived from CZ into microbial biomass, the δ15N signature of microorganisms was evaluated by the Extraction-Fumigation-Extraction method followed by EA-IRMS analysis. This latter investigation was possible because zeolitites were enriched with NH4+ derived from pig-slurry, which have a very high 15N natural abundance that allow to trace microbial incorporation. Soil amended with 5 wt% of NZ showed increased ergosterol content as well as microbial C/N ratio starting from day 9 of incubation, suggesting that fungal biomass was probably favored, although the same behavior was not found in the soil amended with 15 wt% of the same material. On the other hand, the NH4+-enriched CZ showed strong interactions with soil microbial biomass N. Isotopic measurements supported microbial assimilation of the N introduced with CZ since the second day of incubation. The high dissolved organic C and microbial biomass N suggested an increase of mineralization and immobilization processes. In addition, in CZ amended soil, microbial biomass N was related to NO3- production over time and inversely related to NH4+, suggesting high

Biomass ashes from pyrolytic wood liquefaction as novel soil amendments

NASA Astrophysics Data System (ADS)

Fernández-Delgado Juárez, Marina; Gómez Brandón, María; Mazzier, Thomas; Schönegger, Deborah; Hermanns, Roy; Leijenhorst, Evert; Insam, Heribert

2017-04-01

What happens when an old soil amendment is in fact a new one? Traditionally, ashes from biomass combustion were considered as a valuable resource, and widely used as an agricultural soil amendment. However, in recent decades we have been reluctant to apply them to soils, despite the increase in the production of combustion ashes resulting from the development of new fuels derived from biomass residues. The production of Fast Pyrolysis Bio Oil (FPBO) out of various lignocellulosic biomass streams is one of the newest technologies for gaining a liquid biofuel that can be seen as a future substitute for mineral oils. During the pyrolysis process, the by-products (charcoal and low calorific gases) are combusted to generate energy, resulting in the production of ashes that contain the majority of the minerals and salts originally present in the feedstock. The main objective of the present work is to investigate if the recovered ashes from the pyrolysis process can be used as a soil amendment. A greenhouse trial was set up in order to evaluate the impact of the ashes on an acid grassland soil (eutric Cambisol) from the region of Tyrol (Austria). A two-level experimental design (ash treatment, and plant effect) was set up. The ashes were mixed with the soil columns at a ratio of 1% (w:w, fresh weight). A control treatment that consisted of soil without the addition of ashes was also included. Moreover, to understand the effect that the ashes would have on crop growth, ten seeds of a traditional wheat variety (Tiroler Früher Dinkel; Triticum aestivum subsp. spelta), were placed in half of the columns with and without ashes, so as to determine the seed germination index and plant growth. Moreover, specific microbial groups related to N cycle were quantified by real-time PCR. A total of 24 experimental units (2 ash treatments x 2 incubation times x 2 plant levels x 3 replicates) were analysed. After an equilibration period of 24 h at 4 °C (referred as time zero), the

Influence of an iron-rich amendment on chemical lability and plant (Raphanus sativus L.) availability of two metallic elements (As and Pb) on mine-impacted agricultural soils.

PubMed

Kim, Juhee; Kim, Yong-Seong; Hyun, Seunghun; Moon, Deok Hyun; Chang, Jun Young

2016-10-01

Variation of the chemical extractability and phytoavailability of two metallic elements (e.g., As and Pb) on amendment-treated soils was investigated. Four mine-impacted agricultural soils contaminated with both As (174-491 mg kg -1 ) and Pb (116-357 mg kg -1 ) were amended with an iron-rich sludge at the rate of 5 % (w/w). After a 4-, 8-, and 16-week incubation, the extractability of metallic elements was assessed by sequential extraction procedure (SEP; F1-F5). The control without amendment was also run. In amended soils, the labile element mass (i.e., F1 + F2) promptly decreased (15-48 % of As and 5-10 % of Pb) in 4 weeks, but the decrement was continued over 16 weeks up to 70 and 28 % for As and Pb, respectively. The labile mass decrement was quantitatively corresponded with the increment of F3 (bound to amorphous metal oxides). In plant test assessed by radish (Raphanus sativus) grown on the 16-week soils, up to 57 % of As and 28 % of Pb accumulation was suppressed and 10-43 % of growth (i.e., shoot/root elongation and fresh weight) was improved. For both the control and amended soils, element uptake by plant was well correlated with their labile soil concentrations (r 2  = 0.799 and 0.499 for As and Pb, respectively). The results confirmed that the iron-rich material can effectively suppress element uptake during R. sativus seedling growth, most likely due to the chemical stabilization of metallic elements in growth medium.

Assessing the chemical and biological accessibility of the herbicide isoproturon in soil amended with biochar.

PubMed

Sopeña, Fatima; Semple, Kirk; Sohi, Saran; Bending, Gary

2012-06-01

There is considerable current interest in using biochar (BC) as a soil amendment to sequester carbon to mitigate climate change. However, the implications of adding BC to agricultural soil for the environmental fate of pesticides remain unclear. In particular, the effect of biochars on desorption behavior of compounds is poorly understood. This study examined the influence of BC on pesticide chemical and biological accessibility using the herbicide isoproturon (IPU). Soils amended with 1% and 2% BC showed enhanced sorption, slower desorption, and reduced biodegradation of IPU. Addition of 0.1% BC had no effect on sorption, desorption or biodegradation of IPU. However, the mineralization of (14)C-IPU was reduced by all BC concentrations, reducing by 13.6%, 40.1% and 49.8% at BC concentrations of 0.1%, 1% and 2% respectively. Further, the ratio of the toxic metabolite 4-isopropyl-aniline to intact IPU was substantially reduced by higher BC concentrations. Hydroxypropyl-β-cyclodextrin (HPCD) extractions were used to estimate the IPU bioaccessibility in the BC-amended soil. Significant correlations were found between HPCD-extracted (14)C-IPU and the IPU desorbed (%) (r(2)=0.8518, p<0.01), and also the (14)C-IPU mineralized (%) (r(2)=0.733; p<0.01) for all BC-amended soils. This study clearly demonstrates how desorption in the presence of BC is intimately related to pesticide biodegradation by the indigenous soil microbiota. BC application to agricultural soils can affect the persistence of pesticides as well as the fate of their degradation products. This has important implications for the effectiveness of pesticides as well as the sequestration of contaminants in soils. Copyright © 2012 Elsevier Ltd. All rights reserved.

Enzymatic activities in a semiarid soil amended with different soil treatment: Soil quality improvement

NASA Astrophysics Data System (ADS)

Hueso González, Paloma; Elbl, Jakub; Dvořáčková, Helena; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

2017-04-01

The use of soil quality indicators may be an effective approach to assess the positive effect of the organic amendment as good restoration methods. Relying on the natural fertility of the soil, the most commonly chemical and physical parameters used to evaluate soil quality are depend to the soil biological parameters. The measurement of soil basal respiration and the mineralization of organic matter are commonly accepted as a key indicator for measuring changes to soil quality. Thus, the simultaneous measurement of various enzymes seems to be useful to evaluate soil biochemical activity and related processes. In this line, Dehydrogenase activity is widely used in evaluating the metabolic activity of soil microorganisms and to evaluate the effects caused by the addition of organic amendments. Variations in phosphatase activity, apart from indicating changes in the quantity and quality of soil phosphorated substrates, are also good indicators of soil biological status. This study assesses the effect of five soil amendments as restoration techniques for semiarid Mediterrenean ecosystems. The goal is to interpret the status of biological and chemical parameters in each treatment as soil quality indicators in degraded forests. The main objectives were to: i) analyze the effect of various organic amendments on the enzimatic activity of soil; ii) analyze the effect of the amendments on soil respiration; iii) assess the effect of these parameters on the soil chemical properties which are indicative of soil healthy; and iv) evaluated form the land management point of view which amendment could result a effective method to restore Mediterranean degraded areas. An experimental paired-plot layout was established in southern of Spain (homogeneous slope gradient: 7.5%; aspect: N170). Five amendments were applied in an experimental set of plots: straw mulching; mulch with chipped branches of Aleppo Pine (Pinus halepensis Mill.); TerraCotten hydroabsobent polymers; sewage

Assessing the environmental availability of sulfamethoxazole and its acetylated metabolite in agricultural soils amended with compost and manure: an experimental and modeling study

NASA Astrophysics Data System (ADS)

Goulas, Anaïs; Sertillange, Nicolas; Garnier, Patricia; Dumény, Valérie; Bergheaud, Valérie; Benoit, Pierre; Haudin, Claire-Sophie

2017-04-01

The recycling of sludge compost and farmyard manure in agriculture can lead to the introduction of sulfonamide antibiotics and their acetylated metabolites into soils. The quality and the biodegradability of the exogenous organic matter (EOM) containing antibiotic residues is determinant for their environmental availability and fate in soils (Goulas et al., 2016). This study combined experimental and modeling approaches in order to: 1) assess the fraction of sulfamethoxazole (SMX) and N-acetyl-sulfamethoxazole (AcSMX) available in EOM-amended soils by using soft extractions (CaCl2, EDTA or cyclodextrin solutions) during a 28-day incubation; and 2) better understand the dynamics of sulfonamide residues in amended soils in connection with their availability and the mineralization of EOM organic matter thanks to the COP-Soil model (Geng et al. 2015). This model proposes several options to couple the biotransformation of organic pollutants (OP) with the decomposition of EOM in soil. The microbial degradation can be simulated by co-metabolism and specific-metabolism. The model also accounts for the formation of non-extractable residues (NER) via both physicochemical and microbial routes. The available fraction in both soil/EOM mixtures decreased from 56-96% and 31-63% initial 14C-activity for AcSMX and SMX, respectively, to reach 7-33% after 28 days. This high decrease in the first seven days was mainly due to the formation of NER that were more abundant in soil/manure mixtures than in the soil/compost ones. The three aqueous solutions differently extracted the available 14C-residues according to the incubation time, the EOM and the molecule. The mineralized fractions for both 14C-molecules were only 2-3% with a little more mineralization in the soil/manure mixtures than in the soil/compost. By using the COP-Soil model, the dynamics of EOM and OP were well described using parameter values specific to the organic matter mineralization, and this for the three soft

Tropical soils degraded by slash-and-burn cultivation can be recultivated when amended with ashes and compost.

PubMed

Gay-des-Combes, Justine Marie; Sanz Carrillo, Clara; Robroek, Bjorn Jozef Maria; Jassey, Vincent Eric Jules; Mills, Robert Thomas Edmund; Arif, Muhammad Saleem; Falquet, Leia; Frossard, Emmanuel; Buttler, Alexandre

2017-07-01

In many tropical regions, slash-and-burn agriculture is considered as a driver of deforestation; the forest is converted into agricultural land by cutting and burning the trees. However, the fields are abandoned after few years because of yield decrease and weed invasion. Consequently, new surfaces are regularly cleared from the primary forest. We propose a reclamation strategy for abandoned fields allowing and sustaining re-cultivation. In the dry region of south-western Madagascar, we tested, according to a split-plot design, an alternative selective slash-and-burn cultivation technique coupled with compost amendment on 30-year-old abandoned fields. Corn plants ( Zea mays L.) were grown on four different types of soil amendments: no amendment (control), compost, ashes (as in traditional slash-and-burn cultivation), and compost + ashes additions. Furthermore, two tree cover treatments were applied: 0% tree cover (as in traditional slash-and-burn cultivation) and 50% tree cover (selective slash-and-burn). Both corn growth and soil fertility parameters were monitored during the growing season 2015 up to final harvest. The amendment compost + ashes strongly increased corn yield, which was multiplied by 4-5 in comparison with ashes or compost alone, reaching 1.5 t/ha compared to 0.25 and 0.35 t/ha for ashes and compost, respectively. On control plots, yield was negligible as expected on these degraded soils. Structural equation modeling evidenced that compost and ashes were complementary fertilizing pathways promoting soil fertility through positive effects on soil moisture, pH, organic matter, and microbial activity. Concerning the tree cover treatment, yield was reduced on shaded plots (50% tree cover) compared to sunny plots (0% tree cover) for all soil amendments, except ashes. To conclude, our results provide empirical evidence on the potential of recultivating tropical degraded soils with compost and ashes. This would help mitigating deforestation of the

Long-term manure amendments reduced soil aggregate stability via redistribution of the glomalin-related soil protein in macroaggregates

PubMed Central

Xie, Hongtu; Li, Jianwei; Zhang, Bin; Wang, Lianfeng; Wang, Jingkuan; He, Hongbo; Zhang, Xudong

2015-01-01

Glomalin-related soil protein (GRSP) contributes to the formation and maintenance of soil aggregates, it is however remains unclear whether long-term intensive manure amendments alter soil aggregates stability and whether GRSP regulates these changes. Based on a three-decade long fertilization experiment in northeast China, this study examined the impact of long-term manure input on soil organic carbon (SOC), total and easily extractable GRSP (GRSPt and GRSPe) and their respective allocations in four soil aggregates (>2000 μm; 2000–250 μm; 250–53 μm; and <53 μm). The treatments include no fertilization (CK), low and high manure amendment (M1, M2), chemical nitrogen, phosphorus and potassium fertilizers (NPK), and combined manure and chemical fertilizers (NPKM1, NPKM2). Though SOC, GRSPe and GRSPt in soil and SOC in each aggregate generally increased with increasing manure input, GRSPt and GRSPe in each aggregate showed varying changes with manure input. Both GRSP in macroaggregates (2000–250 μm) were significantly higher under low manure input, a pattern consistent with changes in soil aggregate stability. Constituting 38~49% of soil mass, macroaggregates likely contributed to the nonlinear changes of aggregate stability under manure amendments. The regulatory process of GRSP allocations in soil aggregates has important implications for manure management under intensive agriculture. PMID:26423355

AMENDING SOILS WITH PHOSPHATE AS MEANS TO ...

EPA Pesticide Factsheets

Ingested soil and surface dust may be important contributors to elevated blood lead (Pb) levels in children exposed to Pb contaminated environments. Mitigation strategies have typically focused on excavation and removal of the contaminated soil. However, this is not always feasible for addressing widely disseminated contamination in populated areas often encountered in urban environments. The rationale for amending soils with phosphate is that phosphate will promote formation of highly insoluble Pb species (e.g., pyromorphite minerals) in soil, which will remain insoluble after ingestion and, therefore, inaccessible to absorption mechanisms in the gastrointestinal tract (GIT). Amending soil with phosphate might potentially be used in combination with other methods that reduce contact with or migration of contaminated soils, such as covering the soil with a green cap such as sod, clean soil with mulch, raised garden beds, or gravel. These remediation strategies may be less expensive and far less disruptive than excavation and removal of soil. This review evaluates evidence for efficacy of phosphate amendments for decreasing soil Pb bioavailability. Evidence is reviewed for (1) physical and chemical interactions of Pb and phosphate that would be expected to influence bioavailability, (2) effects of phosphate amendments on soil Pb bioaccessibility (i.e., predicted solubility of Pb in the GIT), and (3) results of bioavailability bioassays of amended soils con

The Effects of Various Amendments on Trace Element Stabilization in Acidic, Neutral, and Alkali Soil with Similar Pollution Index

PubMed Central

Kim, Min-Suk; Min, Hyun-Gi; Lee, Sang-Hwan; Kim, Jeong-Gyu

2016-01-01

Many studies have examined the application of soil amendments, including pH change-induced immobilizers, adsorbents, and organic materials, for soil remediation. This study evaluated the effects of various amendments on trace element stabilization and phytotoxicity, depending on the initial soil pH in acid, neutral, and alkali conditions. As in all types of soils, Fe and Ca were well stabilized on adsorption sites. There was an effect from pH control or adsorption mechanisms on the stabilization of cationic trace elements from inorganic amendments in acidic and neutral soil. Furthermore, acid mine drainage sludge has shown great potential for stabilizing most trace elements. In a phytotoxicity test, the ratio of the bioavailable fraction to the pseudo-total fraction significantly affected the uptake of trace elements by bok choy. While inorganic amendments efficiently decreased the bioavailability of trace elements, significant effects from organic amendments were not noticeable due to the short-term cultivation period. Therefore, the application of organic amendments for stabilizing trace elements in agricultural soil requires further study. PMID:27835687

The Effects of Various Amendments on Trace Element Stabilization in Acidic, Neutral, and Alkali Soil with Similar Pollution Index.

PubMed

Kim, Min-Suk; Min, Hyun-Gi; Lee, Sang-Hwan; Kim, Jeong-Gyu

2016-01-01

Many studies have examined the application of soil amendments, including pH change-induced immobilizers, adsorbents, and organic materials, for soil remediation. This study evaluated the effects of various amendments on trace element stabilization and phytotoxicity, depending on the initial soil pH in acid, neutral, and alkali conditions. As in all types of soils, Fe and Ca were well stabilized on adsorption sites. There was an effect from pH control or adsorption mechanisms on the stabilization of cationic trace elements from inorganic amendments in acidic and neutral soil. Furthermore, acid mine drainage sludge has shown great potential for stabilizing most trace elements. In a phytotoxicity test, the ratio of the bioavailable fraction to the pseudo-total fraction significantly affected the uptake of trace elements by bok choy. While inorganic amendments efficiently decreased the bioavailability of trace elements, significant effects from organic amendments were not noticeable due to the short-term cultivation period. Therefore, the application of organic amendments for stabilizing trace elements in agricultural soil requires further study.

Organic and inorganic amendments affect soil concentration and accumulation of cadmium and lead in wheat in calcareous alkaline soils

USDA-ARS?s Scientific Manuscript database

Irrigation with untreated effluent in periurban agriculture could result in accumulation and bioconcentrations of cadmium (Cd) and lead (Pb). Different amendments were used to investigate their effect on availability, concentration, and uptake of metals by wheat in texturally different soils. Crop w...

The application of soil amendments benefits to the reduction of phosphorus depletion and the growth of cabbage and corn.

PubMed

Liu, Wei; Ji, Hongli; Kerr, Philip; Wu, Yonghong; Fang, Yanming

2015-11-01

The loss of phosphorus from agricultural intensive areas can cause ecological problems such as eutrophication in downstream surface waters. Therefore, the purpose of this study is to control the phosphorus loss using environmentally benign soil amendments, viz, ferrous sulfate (FES), aluminum sulfate (ALS), and polyacrylamide (PAM). The phosphorus concentration changes in soil and leaching solution, the morphological index of plant (including stem and root), and root activity and quality (represented by chlorophyll and soluble sugar) at different growth stages of cabbage (Brassica oleracea L. var. capitata L.) were monitored in a pilot experiment. Phosphorus contents in soil and runoff were also investigated in field experiments cultivated with corn (Zea mays L.). The results show that the application of these amendments improved the phosphorus uptake by cabbage and corn, resulting in the enhanced morphologies of root and stem as well as the root activity at the early and middle stages of cabbage growth. The soil total phosphorus and available phosphorus in soils treated with FES, ALS, and PAM declined, resulting in lower concentrations of phosphorus in the leachate and the soil runoff. During the use of the soil amendments, the cabbage quality measures, determined as chlorophyll and soluble sugar in leaves, were not significantly different from those in the control. It is suggested that the application of these soil amendments is safe for cabbage production under single season cropping conditions, and the use of these three amendments is a promising measure to reduce phosphorus loss in intensive agricultural areas.

Enzyme Sorption onto Soil and Biocarbon Amendments Alters Catalytic Capacity and Depends on the Specific Protein and pH

NASA Astrophysics Data System (ADS)

Foster, E.; Fogle, E. J.; Cotrufo, M. F.

2017-12-01

Enzymes catalyze biogeochemical reactions in soils and play a key role in nutrient cycling in agricultural systems. Often, to increase soil nutrients, agricultural managers add organic amendments and have recently experimented with charcoal-like biocarbon products. These amendments can enhance soil water and nutrient holding capacity through increasing porosity. However, the large surface area of the biocarbon has the potential to sorb nutrients and other organic molecules. Does the biocarbon decrease nutrient cycling through sorption of enzymes? In a laboratory setting, we compared the interaction of two purified enzymes β-glucosidase and acid phosphatase with a sandy clay loam and two biocarbons. We quantified the sorbed enzymes at three different pHs using a Bradford protein assay and then measured the activity of the sorbed enzyme via high-throughput fluorometric analysis. Both sorption and activity depended upon the solid phase, pH, and specific enzyme. Overall the high surface area biocarbon impacted the catalytic capacity of the enzymes more than the loam soil, which may have implications for soil nutrient management with these organic amendments.

Bioavailability of silver and silver sulfide nanoparticles to lettuce (Lactuca sativa): Effect of agricultural amendments on plant uptake.

PubMed

Doolette, Casey L; McLaughlin, Michael J; Kirby, Jason K; Navarro, Divina A

2015-12-30

Silver nanoparticles (AgNPs) can enter terrestrial systems as sulfidised AgNPs (Ag2S-NPs) through the application of biosolids to soil. However, the bioavailability of Ag2S-NPs in soils is unknown. The two aims of this study were to investigate (1) the bioavailability of Ag to lettuce (Lactuca sativa) using a soil amended with biosolids containing Ag2S-NPs and (2) the effect of commonly used agricultural fertilisers/amendments on the bioavailability of Ag, AgNPs and Ag2S-NPs to lettuce. The study used realistic AgNP exposure pathways and exposure concentrations. The plant uptake of Ag from biosolids-amended soil containing Ag2S-NPs was very low for all Ag treatments (0.02%). Ammonium thiosulfate and potassium chloride fertilisation significantly increased the Ag concentrations of plant roots and shoots. The extent of the effect varied depending on the type of Ag. Ag2S-NPs, the realistic form of AgNPs in soil, had the lowest bioavailability. The potential risk of AgNPs in soils is low; even in the plants that had the highest Ag concentrations (Ag(+)+thiosulfate), only 0.06% of added Ag was found in edible plant parts (shoots). Results from the study suggest that agricultural practises must be considered when carrying out risk assessments of AgNPs in terrestrial systems; such practises can affect AgNP bioavailability. Copyright © 2015 Elsevier B.V. All rights reserved.

Environmental fate of roxarsone in poultry litter. Part II. Mobility of arsenic in soils amended with poultry litter

USGS Publications Warehouse

Rutherford, D.W.; Bednar, A.J.; Garbarino, J.R.; Needham, R.; Staver, K.W.; Wershaw, R. L.

2003-01-01

Poultry litter often contains arsenic as a result of organo-arsenical feed additives. When the poultry litter is applied to agricultural fields, the arsenic is released to the environment and may result in increased arsenic in surface and groundwater and increased uptake by plants. The release of arsenic from poultry litter, litter-amended soils, and soils without litter amendment was examined by extraction with water and strong acids (HCI and HN03). The extracts were analyzed for As, C, P, Cu, Zn, and Fe. Copper, zinc, and iron are also poultry feed additives. Soils with a known history of litter application and controlled application rate of arsenic-containing poultry litter were obtained from the University of Maryland Agricultural Experiment Station. Soils from fields with long-term application of poultry litter were obtained from a tilled field on the Delmarva Peninsula (MD) and an untilled Oklahoma pasture. Samples from an adjacent forest or nearby pasture that had no history of litter application were used as controls. Depth profiles were sampled for the Oklahoma pasture soils. Analysis of the poultry litter showed that 75% of the arsenic was readily soluble in water. Extraction of soils shows that weakly bound arsenic mobilized by water correlates positively with C, P, Cu, and Zn in amended fields and appears to come primarily from the litter. Strongly bound arsenic correlates positively with Fe in amended fields and suggests sorption or coprecipitation of As and Fe in the soil column.

Effects of conventional and no-tillage soil management and compost and sludge amendment on soil CO2 fluxes and microbial activities

NASA Astrophysics Data System (ADS)

Garcia-Gil, Juan Carlos; Haller, Isabel; Soler-Rovira, Pedro; Polo, Alfredo

2010-05-01

Soil management exerts a significant influence on the dynamic of soil organic matter, which is a key issue to enhance soil quality and its ecological functions, but also affects to greenhouse gas emissions and C sequestration processes. The objective of the present research was to determine the influence of soil management (conventional deep-tillage and no-tillage) and the application of two different organic amendment -thermally-dry sewage sludge (TSL) and municipal waste compost (MWC)- on soil CO2 fluxes and microbial activities in a long-term field experiment under semi-arid conditions. Both organic amendments were applied at a rate of 30 t ha-1 prior to sowing a barley crop. The experiment was conducted on an agricultural soil (Calcic Luvisol) from the experimental farm "La Higueruela" (Santa Olalla, Toledo). Unamended soils were used as control in both conventional and no-tillage management. During the course of the experiment, soil CO2 fluxes, microbial biomass C (MBC) and enzyme activities involved in the biogeochemical cycles of C, N and P were monitored during 12 months. The results obtained during the experiment for soil CO2 fluxes showed a great seasonal fluctuation due to semi-arid climate conditions. Overall, conventional deep-tillage soils exhibited higher CO2 fluxes, which was particularly larger during the first hours after deep-tillage was performed, and smaller MBC content and significantly lower dehydrogenase, beta-glucosidase, phosphatase, urease and BAA protease activities than no-tillage soils. Both MWC and TSL amendments provoked a significant increase of CO2 fluxes in both conventional and no-tillage soils, which was larger in TSL amended soils and particularly in no-tillage soils. The application of these organic amendments also enhanced MBC content and the overall enzyme activities in amended soils, which indicate a global revitalization of soil microbial metabolism in response to the fresh input of organic compounds that are energy

Nitrous oxide production from soils amended with biogas residues and cattle slurry.

PubMed

Abubaker, J; Odlare, M; Pell, M

2013-07-01

The amount of residues generated from biogas production has increased dramatically due to the worldwide interest in renewable energy. A common way to handle the residues is to use them as fertilizers in crop production. Application of biogas residues to agricultural soils may be accompanied with environmental risks, such as increased NO emission. In 24-d laboratory experiments, NO dynamics and total production were studied in arable soils (sandy, clay, and organic) amended with one of two types of anaerobically digested biogas residues (BR-A and BR-B) generated from urban and agricultural waste and nondigested cattle slurry (CS) applied at rates corresponding to 70 kg NH-N ha. Total NO-N losses from the sandy soil were higher after amendment with BR-B (0.32 g NO-N m) than BR-A or CS (0.02 and 0.18 g NO-N m, respectively). In the clay soil, NO-N losses were very low for CS (0.02 g NO-N m) but higher for BR-A and BR-B (0.25 and 0.15 g NO-N m, respectively). In the organic soil, CS gave higher total NO-N losses (0.31 g NO-N m) than BR-A or BR-B (0.09 and 0.08 g NO-N m, respectively). Emission peaks differed considerably between soils, occurring on Day 1 in the organic soil and on Days 11 to 15 in the sand, whereas in the clay the peak varied markedly (Days 1, 6, and 13) depending on residue type. In all treatments, NH concentration decreased with time, and NO concentration increased. Potential ammonium oxidation and potential denitrification activity increased significantly in the amended sandy soil but not in the organic soil and only in the clay amended with CS. The results showed that fertilization with BR can increase NO emissions and that the size is dependent on the total N and organic C content of the slurry and on soil type. In conclusion, the two types of BR and the CS are not interchangeable regarding their effects on NO production in different soils, and, hence, matching fertilizer type to soil type could reduce NO emissions. For instance, it could be

Fate of classical faecal bacterial markers and ampicillin-resistant bacteria in agricultural soils under Mediterranean climate after urban sludge amendment.

PubMed

Gondim-Porto, Clarissa; Platero, Leticia; Nadal, Ignacio; Navarro-García, Federico

2016-09-15

The use of sewage sludge or biosolids as agricultural amendments may pose environmental and human health risks related to pathogen or antibiotic-resistant microorganism transmission from soils to vegetables or to water through runoff. Since the survival of those microorganisms in amended soils has been poorly studied under Mediterranean climatic conditions, we followed the variation of soil fecal bacterial markers and ampicillin-resistant bacteria for two years with samplings every four months in a split block design with three replica in a crop soil where two different types of biosolids (aerobically or anaerobically digested) at three doses (low, 40; intermediate, 80; and high, 160Mg·ha(-1)) were applied. Low amounts of biosolids produced similar decay rates of coliform populations than in control soil (-0.19 and -0.27log10CFUs·g(-1)drysoilmonth(-1) versus -0.22) while in the case of intermediate and high doses were close to zero and their populations remained 24months later in the range of 4-5log10CFUs·g(-1)ds. Enterococci populations decayed at different rates when using aerobic than anaerobic biosolids although high doses had higher rates than control (-0.09 and -0.13log10CFUs·g(-1)dsmonth(-1) for aerobic and anaerobic, respectively, vs -0.07). At the end of the experiment, counts in high aerobic and low and intermediate anaerobic plots were 1 log10 higher than in control (4.21, 4.03, 4.2 and 3.11log10CFUs·g(-1) ds, respectively). Biosolid application increased the number of Clostridium spores in all plots at least 1 log10 with respect to control with a different dynamic of decay for low and intermediate doses of aerobic and anaerobic sludge. Ampicillin-resistant bacteria increased in amended soils 4months after amendment and remained at least 1 log10 higher 24months later, especially in aerobic and low and intermediate anaerobic plots due to small rates of decay (in the range of -0.001 to -0.008log10CFUs·g(-1)dsmonth(-1) vs -0.016 for control). Aerobic

Effect of ageing on the availability of heavy metals in soils amended with compost and biochar: evaluation of changes in soil and amendment properties.

PubMed

Venegas, A; Rigol, A; Vidal, M

2016-10-01

Remediation strategies using soil amendments should consider the time dependence of metal availability to identify amendments that can sustainably reduce available pollutant concentrations over time. Drying-wetting cycles were applied on amendments, soils and soil + amendment mixtures, to mimic ageing at field level and investigate its effect on extractable Cd, Cu, Ni, Pb and Zn concentrations from three contaminated soils. The amendments investigated were municipal waste organic compost and biochars. The amendments, soils and mixtures were characterised by their physicochemical properties at different ageing times. The amendments were also characterised in terms of sorption capacity for Cd and Cu. The sorption capacity and the physicochemical properties of the amendments remained constant over the period examined. When mixed with the soils, amendments, especially the compost, immediately reduced the extractable metals in the soils with low pH and acid neutralisation capacity, due to the increase in pH and buffering capacity of the mixtures. The amendments had a relatively minor impact on the metal availability concentrations for the soil with substantially high acid neutralisation capacity. The most important changes in extractable metal concentrations were observed at the beginning of the experiments, ageing having a minor effect on metal concentrations when compared with the initial effect of amendments.

Short-term effect of the soil amendments activated carbon, biochar, and ferric oxyhydroxide on bacteria and invertebrates.

PubMed

Hale, Sarah E; Jensen, John; Jakob, Lena; Oleszczuk, Patryk; Hartnik, Thomas; Henriksen, Thomas; Okkenhaug, Gudny; Martinsen, Vegard; Cornelissen, Gerard

2013-08-06

The aim of the present study was to evaluate the secondary ecotoxicological effects of soil amendment materials that can be added to contaminated soils in order to sequester harmful pollutants. To this end, a nonpolluted agricultural soil was amended with 0.5, 2, and 5% of the following four amendments: powder activated carbon (PAC), granular activated carbon, corn stover biochar, and ferric oxyhydroxide powder, which have previously been proven to sequester pollutants in soil. The resulting immediate effects (i.e., without aging the mixtures before carrying out tests) on the springtail Folsomia candida, the earthworm species Aporectodea caliginosa and Eisenia fetida, the marine bacteria Vibrio fischeri, a suite of ten prokaryotic species, and a eukaryote (the yeast species Pichia anomalia) were investigated. Reproduction of F. candida was significantly increased compared to the unamended soil when 2% biochar was added to it. None of the treatments caused a negative effect on reproduction. All amendments had a deleterious effect on the growth of A. caliginosa when compared to the unamended soil, except the 0.5% amendment of biochar. In avoidance tests, E. fetida preferred biochar compared to all other amendments including the unamended soil. All amendments reduced the inhibition of luminescence to V. fischeri, i.e., were beneficial for the bacteria, with PAC showing the greatest improvement. The effects of the amendments on the suite of prokaryotic species and the eukaryote were variable, but overall the 2% biochar dose provided the most frequent positive effect on growth. It is concluded that the four soil amendments had variable but never strongly deleterious effects on the bacteria and invertebrates studied here during the respective recommended experimental test periods.

Environmental risk assessment of the use of different organic wastes as soil amendments

NASA Astrophysics Data System (ADS)

Alvarenga, Paula; Palma, Patrícia; Mourinha, Clarisse; Farto, Márcia; Cunha-Queda, Ana Cristina; Natal-da-Luz, Tiago; Sousa, José Paulo

2013-04-01

The use of organic wastes in agriculture is considered a way of maintaining or restoring the quality of soils, enlarging the slow cycling soil organic carbon pool. However, a wide variety of undesired substances, such as potentially trace elements and organic contaminants, can have adverse effects on the environment. That fact was highlighted by the Proposal for a Soil Framework Directive, which recognized that "soil degradation or soil improvements have a major impact on other areas, (…) such as surface waters and groundwater, human health, climate change, protection of nature and biodiversity, and food safety". Taking that into account, the research project "ResOrgRisk" aims to assess the environmental risk involved in the use of different organic wastes as soil amendments, evidencing their benefits and constraints, and defining the most suitable tests to reach such assessment. The organic wastes selected for this purpose were: sewage sludge, limed, not limed, and co-composted with agricultural wastes, agro-industrial sludge, mixed municipal solid waste compost, compost produced from organic farming residues, and pig slurry digestate. Whereas threshold values for heavy metals in sludge used for agriculture have been set by the European Commission, actually there is no definitive European legislation for organic contaminants. Guide values for some organic contaminants (e.g. polychlorinated biphenyls - PCBs, and polycyclic aromatic hydrocarbons - PAHs) have been adopted at national level by many European countries, such as Portugal. These values should be taken into account when assessing the risk involved in the use of organic wastes as soil amendments. However, chemical analysis of organic waste often gives scarce information because it does not include possible interactions between chemicals. Furthermore, an exhaustive identification and quantification of all substances is impractical. In this study, ecotoxicological tests (comprising solid and aquatic phases

Raw or incubated olive-mill wastes and its biotransformed products as agricultural soil amendments-effect on sorption-desorption of triazine herbicides.

PubMed

Delgado-Moreno, Laura; Almendros, Gonzalo; Peña, Aránzazu

2007-02-07

Raw olive-mill waste and soil amendments obtained from their traditional composting or vermicomposting were added, at rates equivalent to 200 Mg ha-1, to a calcareous silty clay loam soil in a laboratory test, in order to improve its fertility and physicochemical characteristics. In particular, the effects on the sorption-desorption processes of four triazine herbicides have been examined. We found that comparatively hydrophobic herbicides terbuthylazine and prometryn increased their retention on amended soil whereas the more polar herbicides simazine and cyanazine were less affected. Soil application of olive cake, without transformation, resulted in the highest herbicide retention. Its relatively high content in aliphatic fractions and lipids could explain the increased herbicide retention through hydrophobic bonding and herbicide diffusion favored by poorly condensed macromolecular structures. On the other hand, the condensed aromatic structure of the compost and vermicompost from olive cake could hinder diffusion processes, resulting in lower herbicide sorption. In fact, the progressive humification in soil of olive-mill solid waste led to a decrease of sorption capacity, which suggested important changes in organic matter quality and interactions during the mineralization process. When soil amended with vermicompost was incubated for different periods of time, the enhanced herbicide sorption capacity persisted for 2 months. Pesticide desorption was reduced by the addition of fresh amendments but was enhanced during the transformation process of amendments in soil. Our results indicate the potential of soil amendments based on olive-mill wastes in the controlled, selective release of triazine herbicides, which varies depending on the maturity achieved by their biological transformation.

Alum amendment effects on phosphorus release and distribution in poultry litter-amended sandy soils

USGS Publications Warehouse

Staats, K.E.; Arai, Y.; Sparks, D.L.

2004-01-01

Increased poultry production has contributed to excess nutrient problems in Atlantic Coastal Plain soils due to land application of poultry litter (PL). Aluminum sulfate [alum, Al2(SO4)3?? 14H2O] amendment of PL effectively reduces soluble phosphorus (P) in the PL; however, the effects of these litters when added to acidic, sandy soils are not well understood. The objective of this study was to investigate the efficacy of alum-amended poultry litter in reducing P release from three Delaware Coastal Plain soils: Evesboro loamy sand (Ev; excessively drained, mesic, coated Typic Quartzipsamments), Rumford loamy sand (Ru; well drained, coarse-loamy, siliceous, subactive, thermic Typic Hapludults), and Pocomoke sandy loam (Pm; very poorly drained, coarse-loamy, siliceous, active, thermic Typic Umbraquults). Long-term (25 d) and short-term (24 h) desorption studies were conducted, in addition to chemical extractions and kinetic modeling, to observe the changes that alum-amended versus unamended PL caused in the soils. The Ev, Ru, and Pm soils were incubated with 9 Mg ha-1 of alum-amended or unamended PL. Long-term desorption (25 d) of the incubated material resulted in approximately 13.5% (Ev), 12.7% (Ru), and 13.3% (Pm) reductions in cumulative P desorbed when comparing soil treated with unamended and alum-amended PL. In addition, the P release from the soil treated with alum-amended litter was not significantly different from the control (soil alone). Short-term desorption (24 h) showed 7.3% (Ev), 15.4% (Ru), and 20% (Pm) reductions. The overall implication from this study is that the use of alum as a PL amendment is useful in coarse-textured soils of the Coastal Plain. With increased application of alum-amended PL, more significant decreases may be possible with little or no effect on soil quality.

Reduced nitrification and abundance of ammonia-oxidizing bacteria in acidic soil amended with biochar.

PubMed

Wang, Zhenyu; Zong, Haiying; Zheng, Hao; Liu, Guocheng; Chen, Lei; Xing, Baoshan

2015-11-01

Adding biochar into soils has potential to manipulate soil nitrification process due to its impacts on nitrogen (N) cycling, however, the exact mechanisms underlying the alteration of nitrification process in soils are still not clear. Nitrification in an acidic orchard soil amended with peanut shell biochar (PBC) produced at 400 °C was investigated. Nitrification was weakened by PBC addition due to the decreased NH4(+)-N content and reduced ammonia-oxidizing bacteria (AOB) abundance in PBC-amended soils. Adding phenolic compounds (PHCs) free biochar (PBC-P) increased the AOB abundance and the DGGE band number, indicating that PHCs remaining in the PBC likely reduced AOB abundance and diversity. However, PBC addition stimulated rape growth and increased N bioavailability. Overall, adding PBC could suppress the nitrification process and improve N bioavailability in the agricultural soils, and thus possibly mitigate the environmental negative impacts and improving N use efficiency in the acidic soils added with N fertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of the use potential of edible sea urchins (Paracentrotus lividus) processing waste within the agricultural system: influence on soil chemical and biological properties and bean (Phaseolus vulgaris) and wheat (Triticum vulgare) growth in an amended acidic soil.

PubMed

Garau, Giovanni; Castaldi, Paola; Deiana, Salvatore; Campus, Paolo; Mazza, Antonio; Deiana, Pietrino; Pais, Antonio

2012-10-30

assessed in a pot experiment. Plant growth was unaffected (wheat) or stimulated (bean) by the amendment addition in the 0.5-3.0% range while the higher amendment rate (i.e. 5.0%) was detrimental for both plant species indicating a phytotoxic effect which could be due to different factors such as an excess of calcium in soil, a suppression of Mg uptake or the higher EC values detected at the highest amendment rate. It is concluded that ground P. lividus endoskeletons have potential as a soil amendment to ameliorate chemical and biological properties of acidic Mediterranean soils. This seems particularly relevant, especially at the lower amendment rates, since for the first time, a sustainable management system is proposed for P. lividus processing waste, which foresees economic value in the sea urchin by-product through its re-use within the agricultural production system. Copyright © 2012 Elsevier Ltd. All rights reserved.

Humic Acid-Oxidizing, Nitrate-Reducing Bacteria in Agricultural Soils

PubMed Central

Van Trump, J. Ian; Wrighton, Kelly C.; Thrash, J. Cameron; Weber, Karrie A.; Andersen, Gary L.; Coates, John D.

2011-01-01

ABSTRACT This study demonstrates the prevalence, phylogenetic diversity, and physiology of nitrate-reducing microorganisms capable of utilizing reduced humic acids (HA) as electron donors in agricultural soils. Most probable number (MPN) enumeration of agricultural soils revealed large populations (104 to 106 cells g−1 soil) of microorganisms capable of reducing nitrate while oxidizing the reduced HA analog 2,6-anthrahydroquinone disulfonate (AH2DS) to its corresponding quinone. Nitrate-dependent HA-oxidizing organisms isolated from agricultural soils were phylogenetically diverse and included members of the Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Advective up-flow columns inoculated with corn plot soil and amended with reduced HA and nitrate supported both HA oxidation and enhanced nitrate reduction relative to no-donor or oxidized HA controls. The additional electron donating capacity of reduced HA could reasonably be attributed to the oxidation of reduced functional groups. Subsequent 16S rRNA gene-based high-density oligonucleotide microarray (PhyloChip) indicated that reduced HA columns supported the development of a bacterial community enriched with members of the Acidobacteria, Firmicutes, and Betaproteobacteria relative to the no-donor control and initial inoculum. This study identifies a previously unrecognized role for HA in stimulating denitrification processes in saturated soil systems. Furthermore, this study indicates that reduced humic acids impact soil geochemistry and the indigenous bacterial community composition. PMID:21750120

Sorption kinetics and leachability of heavy metal from the contaminated soil amended with immobilizing agent (humus soil and hydroxyapatite).

PubMed

Chaturvedi, Pranav Kumar; Seth, Chandra Shekhar; Misra, Virendra

2006-08-01

Release of heavy metals onto the soil as a result of agricultural and industrial activities may pose a serious threat to the environment. This study investigated the kinetics of sorption of heavy metals on the non-humus soil amended with (1:3) humus soil and 1% hydroxyapatite used for in situ immobilization and leachability of heavy metals from these soils. For this, a batch equilibrium experiment was performed to evaluate metal sorption in the presence of 0.05 M KNO(3) background electrolyte solutions. The Langmuir isotherms applied for sorption studies showed that the amount of metal sorbed on the amended soil decreased in the order of Pb(2+)>Zn(2+)>Cd(2+). The data suggested the possibility of immobilization of Pb due to sorption process and immobilization of Zn and Cd by other processes like co-precipitation and ion exchange. The sorption kinetics data showed the pseudo-second-order reaction kinetics rather than pseudo-first-order kinetics. Leachability study was performed at various pHs (ranging from 3 to 10). Leachability rate was slowest for the Pb(2+) followed by Zn(2+) and Cd(2+). Out of the metal adsorbed on the soil only 6.1-21.6% of Pb, 7.3-39% of Zn and 9.3-44.3% of Cd leached out from the amended soil.

Heavy metal concentrations in earthworms from soil amended with sewage sludge

USGS Publications Warehouse

Beyer, W.N.; Chaney, R.L.; Mulhern, B.M.

1982-01-01

Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P . < 0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P < 0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P < 0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

Occurrence of veterinary antibiotics and progesterone in broiler manure and agricultural soil in Malaysia.

PubMed

Ho, Yu Bin; Zakaria, Mohamad Pauzi; Latif, Puziah Abdul; Saari, Nazamid

2014-08-01

Repeated applications of animal manure as fertilizer are normal agricultural practices that may release veterinary antibiotics and hormones into the environment from treated animals. Broiler manure samples and their respective manure-amended agricultural soil samples were collected in selected locations in the states of Selangor, Negeri Sembilan and Melaka in Malaysia to identify and quantify veterinary antibiotic and hormone residues in the environment. The samples were analyzed using ultrasonic extraction followed by solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The broiler manure samples were found to be contaminated with at least six target analytes, namely, doxycycline, enrofloxacin, flumequine, norfloxacin, trimethoprim and tylosin. These analytes were detected in broiler manure samples with maximum concentrations reaching up to 78,516 μg kg(-1) dry weight (DW) (doxycycline). For manure-amended agricultural soil samples, doxycycline and enrofloxacin residues were detected in every soil sample. The maximum concentration of antibiotic detected in soil was 1331 μg kg(-1) DW (flumequine). The occurrence of antibiotics and hormones in animal manure at high concentration poses a risk of contaminating agricultural soil via fertilization with animal manure. Some physico-chemical parameters such as pH, total organic carbon (TOC) and metal content played a considerable role in the fate of the target veterinary antibiotics and progesterone in the environment. It was suggested that these parameters can affect the adsorption of pharmaceuticals to solid environmental matrices. Copyright © 2014 Elsevier B.V. All rights reserved.

Soil amendment affects Cd uptake by wheat - are we underestimating the risks from chloride inputs?

PubMed

Dahlin, A Sigrun; Eriksson, Jan; Campbell, Colin D; Öborn, Ingrid

2016-06-01

Many parts of the world are investigating the efficacy of recycling nutrient resources to agriculture from different industry and domestic sectors as part of a more circular economy. The complex nature of recycled products as soil amendments coupled to the large diversity of soil types and their inherent properties make it difficult to optimize the benefits and minimize the risks from potentially toxic elements often present in recycled materials. Here we investigated how wheat grain cadmium (Cd) concentration was affected by soil amendments, namely human urine and biogas digestate compared to traditional farm manures and mineral fertilizers. We show that Cl(-) inadvertently added to soils with e.g. urine or biogas digestate strongly increased crop Cd concentrations, largely by mobilizing inherent soil Cd. This resulted in wheat grain Cd levels that could result in exceeding recommended WHO limits for dietary intake. This was evident even in soils with low inherent Cd content and when Cd inputs were low. The future of a circular economy that helps to underpin global food security needs to ensure that the effects of applying complex materials to different types of agricultural land are fully understood and do not jeopardize food safety. Copyright © 2016 Elsevier B.V. All rights reserved.

Linking N2O emissions from biochar-amended soil to the structure and function of the N-cycling microbial community

PubMed Central

Harter, Johannes; Krause, Hans-Martin; Schuettler, Stefanie; Ruser, Reiner; Fromme, Markus; Scholten, Thomas; Kappler, Andreas; Behrens, Sebastian

2014-01-01

Nitrous oxide (N2O) contributes 8% to global greenhouse gas emissions. Agricultural sources represent about 60% of anthropogenic N2O emissions. Most agricultural N2O emissions are due to increased fertilizer application. A considerable fraction of nitrogen fertilizers are converted to N2O by microbiological processes (that is, nitrification and denitrification). Soil amended with biochar (charcoal created by pyrolysis of biomass) has been demonstrated to increase crop yield, improve soil quality and affect greenhouse gas emissions, for example, reduce N2O emissions. Despite several studies on variations in the general microbial community structure due to soil biochar amendment, hitherto the specific role of the nitrogen cycling microbial community in mitigating soil N2O emissions has not been subject of systematic investigation. We performed a microcosm study with a water-saturated soil amended with different amounts (0%, 2% and 10% (w/w)) of high-temperature biochar. By quantifying the abundance and activity of functional marker genes of microbial nitrogen fixation (nifH), nitrification (amoA) and denitrification (nirK, nirS and nosZ) using quantitative PCR we found that biochar addition enhanced microbial nitrous oxide reduction and increased the abundance of microorganisms capable of N2-fixation. Soil biochar amendment increased the relative gene and transcript copy numbers of the nosZ-encoded bacterial N2O reductase, suggesting a mechanistic link to the observed reduction in N2O emissions. Our findings contribute to a better understanding of the impact of biochar on the nitrogen cycling microbial community and the consequences of soil biochar amendment for microbial nitrogen transformation processes and N2O emissions from soil. PMID:24067258

Mineral materials as feasible amendments to stabilize heavy metals in polluted urban soils.

PubMed

Zhang, Mingkui; Pu, Jincheng

2011-01-01

Four minerals, agricultural limestone (AL), rock phosphate (RP), palygorskite (PG), and calcium magnesium phosphate (CMP), were evaluated by means of chemical fractions of heavy metals in soils and concentrations of heavy metals in leachates from columns to determine their ability to stabilize heavy metals in polluted urban soils. Two urban soils (calcareous soil and acidic soil) polluted with cadmium, copper, zinc and lead were selected and amended in the laboratory with the mineral materials) for 12 months. Results indicated that application of the mineral materials reduced exchangeable metals in the sequence of Pb, Cd > Cu > Zn. The reduction of exchangeable fraction of heavy metals in the soils amended with different mineral materials followed the sequence of CMP, PG > AL > RP. Reductions of heavy metals leached were based on comparison with cumulative totals of heavy metals eluted through 12 pore volumes from an untreated soil. The reductions of the metals eluted from the calcareous soil amended with the RP, AL, PG and CMP were 1.98%, 38.89%, 64.81% and 75.93% for Cd, 8.51%, 40.42%, 60.64% and 55.32% for Cu, 1.76%, 52.94%, 70.00% and 74.12% for Pb, and 28.42%, 52.74%, 64.38% and 49.66% for Zn. Those from the acidic soil amended with the CMP, PG, AL, and RP were 25.65%, 68.06%, 78.01% and 79.06% for Cd, 26.56%, 49.64%, 43.40% and 34.68% for Cu, 44.44%, 33.32%, 61.11% and 69.44% for Pb, and 18.46%, 43.77%, 41.98% and 40.68% for Zn. The CMP and PG treatments were superior to the AL and RP for stabilizing heavy metals in the polluted urban soils.

Linear spectral unmixing to monitor crop growth in typical organic and inorganic amended arid soil

NASA Astrophysics Data System (ADS)

El Battay, A.; Mahmoudi, H.

2016-06-01

The soils of the GCC countries are dominantly sandy which is typical of arid regions such as the Arabian Peninsula. Such soils are low in nutrients and have a poor water holding capacity associated with a high infiltration rate. Soil amendments may rehabilitate these soils by restoring essential soil properties and hence enable site revegetation and revitalization for crop production, especially in a region where food security is a priority. In this study, two inorganic amendments; AustraHort and Zeoplant pellet, and one organic locally produced compost were tested as soil amendments at the experimental field of the International Center for Biosaline Agriculture in Dubai, UAE. The main objective is to assess the remote sensing ability to monitor crop growth, for instance Okra (Abelmoschus esculentus), having these amendments, as background with the soil. Three biomass spectral vegetation indices were used namely; NDVI, TDVI and SAVI. Pure spectral signatures of the soil and the three amendments were collected, using a field spectroradiometer, in addition to the spectral signatures of Okra in two growing stages (vegetative and flowering) in the field with a mixed F.O.V of the plant and amended soil during March and May 2015. The spectral signatures were all collected using the FieldSpec® HandHeld 2 (HH2) in the spectral range 325 nm - 1075 nm over 12 plots. A set of 4 plots were assigned for each of the three amendments as follow: three replicates of a 1.5 by 1.5 meter plot with 3kg/m2 of each amendment and 54 plants, one plot as control and all plots were given irrigation treatments at 100% based on ETc. Spectra collected over the plots were inversed in the range of 400-900 nm via a Linear Mixture Model using pure soil and amendments spectral signatures as reference. Field pictures were used to determine the vegetation fraction (in term of area of the F.O.V). Hence, the Okra spectral signatures were isolated for all plots with the three types of amendments. The

Functional Diversity of Microbial Communities in Sludge-Amended Soils

NASA Astrophysics Data System (ADS)

Sun, Y. H.; Yang, Z. H.; Zhao, J. J.; Li, Q.

The BIOLOG method was applied to exploration of functional diversity of soil microbial communities in sludge-amended soils sampled from the Yangtze River Delta. Results indicated that metabolic profile, functional diversity indexes and Kinetic parameters of the soil microbial communities changed following soil amendment with sewage sludge, suggesting that the changes occurred in population of the microbes capable of exploiting carbon substrates and in this capability as well. The kinetic study of the functional diversity revealed that the metabolic profile of the soil microbial communities exhibited non-linear correlation with the incubation time, showing a curse of sigmoid that fits the dynamic model of growth of the soil microbial communities. In all the treatments, except for treatments of coastal fluvo-aquic soil amended with fresh sludge and dried sludge from Hangzhou, kinetic parameters K and r of the functional diversity of the soil microbial communities decreased significantly and parameter S increased. Changes in characteristics of the functional diversity well reflected differences in C utilizing capacity and model of the soil microbial communities in the sludge-amended soils, and changes in functional diversity of the soil microbial communities in a particular eco-environment, like soil amended with sewage sludge.

ADSORPTION OF CADMIUM ON BIOSOLIDS-AMENDED SOILS

EPA Science Inventory

A considerable controversy exists over the biosolid phase (organic or inorganic) responsible for the reduction in phytoavailable Cd in soils amended with biosolids as compared to soils amended with inorganic salts. To test the importance of these two phases, 2 biosolids, 15 bioso...

The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

PubMed

Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

2016-04-01

Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis.

Effects of organic amendments on the mobility of Pb and Zn from mine tailings added to semi-arid soils.

PubMed

Barajas-Aceves, M; Rodríguez-Vázquez, R

2013-01-01

The effects of mine tailings and three organic amendments (compost, bokashi and vermicompost) on the mobility factor for Pb and Zn and on the potential C and N mineralization in semi-arid agricultural and rangeland soils were examined. During the experiment, soil samples were analyzed periodically for CO(2)-C evolution, inorganic N, dehydrogenase activity and percent Pb and Zn mobility during 169 d of incubation. The dehydrogenase activity and CO(2)-C evolved were strongly inhibited by mine tailings mixed with organic compost in both agricultural and rangeland soils (37 to 43 %), followed by N mineralization in treatments with mine tailings plus bokashi or compost (13 to 26.5 %) at 169 d incubation. The highest % mobility of Pb and Zn were observed in soils amended with mine tailings alone, while the lowest was observed in agricultural soils treated with vermicompost plus mine tailings. The CO(2)-C evolved was fitted to first order E, while the cumulative N mineralization was fitted to the linearized power function. Mine tailings were found to influence the potential C and N mineralization rate constants in both soils. The models for C and N mineralization could be used to evaluate the effects of mine tailings, which include intrinsic parameters in the soil.

Long-term use of biosolids as organic fertilizers in agricultural soils: potentially toxic elements occurrence and mobility.

PubMed

Marguí, E; Iglesias, M; Camps, F; Sala, L; Hidalgo, M

2016-03-01

The presence of potentially toxic elements (PTEs) may hinder a more widespread application of biosolids in agriculture. At present, the European Directive 86/278/CEE limit the total concentrations of seven metals (Cu, Cr, Ni, Pb, Zn, Cd and Hg) in agricultural soils and in sewage sludges used as fertilizers but it has not taken into consideration the potential impacts of other emerging micropollutants that may be present in the biosolids as well as their mobility. The aim of this study was to evaluate the accumulation and mobility of 13 elements (including regulated metals and other inorganic species) in agricultural soils repeatedly amended with biosolids for 15 years. Firstly, three digestions programs using different acid mixtures were tested to evaluate the most accurate and efficient method for analysis of soil and sludge. Results demonstrated that sewage sludge application increased concentrations of Pb and Hg in soil, but values did not exceed the quality standard established by legislation. In addition, other elements (As, Co, Sb, Ag, Se and Mn) that at present are not regulated by the Spanish and European directives were identified in the sewage sludge, and significant differences were found between Ag content in soils amended with biosolids in comparison with control soils. This fact can be related to the increasing use of silver nanoparticles in consumer products due to their antibacterial properties. Results from the leaching tests show up that, in general, the mobility degree for both regulated and non-regulated elements in soils amended with biosolids was quite low (<10 %).

The impact of soil amendments on greenhouse gas emissions: a comprehensive life cycle assessment approach

NASA Astrophysics Data System (ADS)

DeLonge, M. S.; Ryals, R.; Silver, W. L.

2011-12-01

Soil amendments, such as compost and manure, can be applied to grasslands to improve soil conditions and enhance aboveground net primary productivity. Applying such amendments can also lead to soil carbon (C) sequestration and, when materials are diverted from waste streams (e.g., landfills, manure lagoons), can offset greenhouse gas (GHG) emissions. However, amendment production and application is also associated with GHG emissions, and the net impact of these amendments remains unclear. To investigate the potential for soil amendments to reduce net GHG emissions, we developed a comprehensive, field-scale life cycle assessment (LCA) model. The LCA includes GHG (i.e., CO2, CH4, N2O) emissions of soil amendment production, application, and ecosystem response. Emissions avoided by diverting materials from landfills or manure management systems are also considered. We developed the model using field observations from grazed annual grassland in northern California (e.g., soil C; above- and belowground net primary productivity; C:N ratios; trace gas emissions from soils, manure piles, and composting), CENTURY model simulations (e.g., long-term soil C and trace gas emissions from soils under various land management strategies), and literature values (e.g., GHG emissions from transportation, inorganic fertilizer production, composting, and enteric fermentation). The LCA quantifies and contrasts the potential net GHG impacts of applying compost, manure, and commercial inorganic fertilizer to grazing lands. To estimate the LCA uncertainty, sensitivity tests were performed on the most widely ranging or highly uncertain parameters (e.g., compost materials, landfill emissions, manure management system emissions). Finally, our results are scaled-up to assess the feasibility and potential impacts of large-scale adoption of soil amendment application as a land-management strategy in California. Our base case results indicate that C sinks and emissions offsets associated with

Effects of biochar amendments on soil microbial biomass and activity.

PubMed

Zhang, H; Voroney, R P; Price, G W

2014-11-01

Environmental benefits reported in the literature of using biochar as a soil amendment are generally increased microbial activity and reduced greenhouse gas (GHG) emissions. This study determined the effects of amendment with biomass feedstocks (spent coffee grounds, wood pellets, and horse bedding compost) and that of biochars (700°C) produced from these feedstocks on soil microbial biomass (C and N) and activity. Soils were amended with these substrates at 0.75% by weight and incubated for up to 175 d under laboratory conditions. Biochar residual effects on soil microbial activity were also studied by amending these soils with either ammonium nitrate (NHNO, 35 mg N kg) or with glucose (864 mg C kg) plus NHNO. Soil microbial biomass C and N, net N mineralization, and CO, NO, and CH emissions were measured. Amendment with biomass feedstocks significantly increased soil microbial biomass and activity, whereas amendment with the biochars had no significant effect. Also, biochar amendment had no significant effect on either net N mineralization or NO and CH emissions from soil. These results indicate that production of biochars at this high temperature eliminated potential substrates. Microbial biomass C in biochar-amended and unamended soils was not significantly different following additions of NHNO or glucose plus NHNO, suggesting that microbial access to otherwise labile C and N was not affected. This study shows that biochars produced at 700°C, regardless of feedstock source, do not enhance soil microbial biomass or activity. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Potential microbial risk factors related to soil amendments and irrigation water of potato crops.

PubMed

Selma, M V; Allende, A; López-Gálvez, F; Elizaquível, P; Aznar, R; Gil, M I

2007-12-01

This study assesses the potential microbial risk factors related to the use of soil amendments and irrigation water on potato crops, cultivated in one traditional and two intensive farms during two harvest seasons. The natural microbiota and potentially pathogenic micro-organisms were evaluated in the soil amendment, irrigation water, soil and produce. Uncomposted amendments and residual and creek water samples showed the highest microbial counts. The microbial load of potatoes harvested in spring was similar among the tested farms despite the diverse microbial levels of Listeria spp. and faecal coliforms in the potential risk sources. However, differences in total coliform load of potato were found between farms cultivated in the autumn. Immunochromatographic rapid tests and the BAM's reference method (Bacteriological Analytical Manual; AOAC International) were used to detect Escherichia coli O157:H7 from the potential risk sources and produce. Confirmation of the positive results by polymerase chain reaction procedures showed that the immunochromatographic assay was not reliable as it led to false-positive results. The potentially pathogenic micro-organisms of soil amendment, irrigation water and soil samples changed with the harvest seasons and the use of different agricultural practices. However, the microbial load of the produce was not always influenced by these risk sources. Improvements in environmental sample preparation are needed to avoid interferences in the use of immunochromatographic rapid tests. The potential microbial risk sources of fresh produce should be regularly controlled using reliable detection methods to guarantee their microbial safety.

Lead in Urban Soils: A Real or Perceived Concern for Urban Agriculture?

PubMed

Brown, Sally L; Chaney, Rufus L; Hettiarachchi, Ganga M

2016-01-01

Urban agriculture is growing in cities across the United States. It has the potential to provide multiple benefits, including increased food security. Concerns about soil contamination in urban areas can be an impediment to urban agriculture. Lead is the most common contaminant in urban areas. In this paper, direct (soil ingestion via outdoor and indoor exposure) and indirect (consumption of food grown in Pb-contaminated soils) exposure pathways are reviewed. It is highly unlikely that urban agriculture will increase incidences of elevated blood Pb for children in urban areas. This is due to the high likelihood that agriculture will improve soils in urban areas, resulting in reduced bioavailability of soil Pb and reduced fugitive dust. Plant uptake of Pb is also typically very low. The exceptions are low-growing leafy crops where soil-splash particle contamination is more likely and expanded hypocotyl root vegetables (e.g., carrot). However, even with higher bioaccumulation factors, it is not clear that the Pb in root vegetables or any other crops will be absorbed after eating. Studies have shown limited absorption of Pb when ingested with food. Best management practices to assure minimal potential for exposure are also common practices in urban gardens. These include the use of residuals-based composts and soil amendments and attention to keeping soil out of homes. This review suggests that benefits associated with urban agriculture far outweigh any risks posed by elevated soil Pb. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Microbial response to salinity stress in a tropical sandy soil amended with native shrub residues or inorganic fertilizer.

PubMed

Sall, Saïdou Nourou; Ndour, Ndèye Yacine Badiane; Diédhiou-Sall, Siré; Dick, Richard; Chotte, Jean-Luc

2015-09-15

Soil degradation and salinization caused by inappropriate cultivation practices and high levels of saltwater intrusion are having an adverse effect on agriculture in Central Senegal. The residues of Piliostigma reticulatum, a local shrub that coexists with crops, were recently shown to increase particulate organic matter and improve soil quality and may be a promising means of alleviating the effects of salinization. This study compared the effects of inorganic fertilizer and P. reticulatum residues on microbial properties and the ability of soil to withstand salinity stress. We hypothesized that soils amended with P. reticulatum would be less affected by salinity stress than soils amended with inorganic fertilizer and control soil. Salinity stress was applied to soil from a field site that had been cultivated for 5 years under a millet/peanut crop rotation when microbial biomass, phospholipid fatty acid (PLFA) community profile, catabolic diversity, microbial activities were determined. Microbial biomass, nitrification potential and dehydrogenase activity were higher by 20%, 56% and 69% respectively in soil with the organic amendment. With salinity stress, the structure and activities of the microbial community were significantly affected. Although the biomass of actinobacteria community increased with salinity stress, there was a substantial reduction in microbial activity in all soils. The soil organically amended was, however, less affected by salinity stress than the control or inorganic fertilizer treatment. This suggests that amendment using P. reticulatum residues may improve the ability of soils to respond to saline conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization of typical diffuse herbicide pollution control by soil amendment configurations under four levels of rainfall intensities.

PubMed

Ouyang, Wei; Huang, Weijia; Wei, Peng; Hao, Fanghua; Yu, Yongyong

2016-06-15

Herbicides are a main source of agricultural diffuse pollution due to their wide application in tillage practices. The aim of this study is to optimize the control efficiency of the herbicide atrazine with the aid of modified soil amendments. The soil amendments were composed of a combination of biochar and gravel. The biochar was created from corn straw with a catalytic pyrolysis of ammonium dihydrogen phosphate. The leaching experiments under four rainfall conditions were measured for the following designs: raw soil, soil amended with gravel, biochar individually and together with gravel. The control efficiency of each design was also identified. With the designed equipment, the atrazine content in the contaminant load layer, gravel substrate layer, biochar amendment layer and soil layer was measured under four types of rainfall intensities (1.25 mm/h, 2.50 mm/h, 5.00 mm/h and 10.00 mm/h). Furthermore, the vertical distribution of atrazine in the soil sections was also monitored. The results showed that the herbicide leaching load increased under the highest rainfall intensity in all designs. The soil with the combination of gravel and biochar provided the highest control efficiency of 87.85% on atrazine when the additional proportion of biochar was 3.0%. The performance assessment under the four kinds of rainfall intensity conditions provided the guideline for the soil amendment configuration. The combination of gravel and biochar is recommended as an efficient method for controlling diffuse herbicide pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phosphate reactivity in long-term poultry litter-amended southern Delaware sandy soils

USGS Publications Warehouse

Arai, Y.; Livi, K.J.T.; Sparks, D.L.

2005-01-01

Eutrophication caused by dissolved P from poultry litter (PL)-amended agricultural soils has been a serious environmental concern in the Delaware-Maryland-Virginia Peninsula (Delmarva), USA. To evaluate state and federal nutrient management strategies for reducing the environmental impact of soluble P from long-term PL-amended Delaware (DE) soils, we investigated (i) inorganic P speciation; (ii) P adsorption capacity; and (iii) the extent of P desorption. Although the electron microprobe (EMP) analyses showed a strong correlation between P and Al/Fe, crystalline Al/Fe-P precipitates were not detected by x-ray diffraction (XRD). Instead, the inorganic P fractionation analyses showed high levels of oxalate extractable P, Al, and Fe fractions (615-858, 1215-1478, and 337-752 mg kg-1, respectively), which were susceptible to slow release during the long-term (30-d) P desorption experiments at a moderately acidic soil pHwater. The labile P in the short-term (24-h) desorption studies was significantly associated with oxalate and F extractable Fe and Al, respectively. This was evident in an 80% reduction maximum in total desorbable P from NH4 oxalate/F pretreated soils. In the adsorption experiments, P was strongly retained in soils at near targeted pH of lime (???6.0), but P adsorption gradually decreased with decreasing pH near the soil pHwater (???5.0). The overall findings suggest that P losses from the can be suppressed by an increase in the P retention capacity of soils via (i) an increase in the number of lime applications to maintain soil pHwater at near targeted pH values, and/or (ii) alum/iron sulfate amendments to provide additional Al- and Fe-based adsorbents. ?? Soil Science Society of America.

Phosphogypsum as a soil fertilizer: Ecotoxicity of amended soil and elutriates to bacteria, invertebrates, algae and plants.

PubMed

Hentati, Olfa; Abrantes, Nelson; Caetano, Ana Luísa; Bouguerra, Sirine; Gonçalves, Fernando; Römbke, Jörg; Pereira, Ruth

2015-08-30

Phosphogypsum (PG) is a metal and radionuclide rich-waste produced by the phosphate ore industry, which has been used as soil fertilizer in many parts of the world for several decades. The positive effects of PG in ameliorating some soil properties and increasing crop yields are well documented. More recently concerns are emerging related with the increase of metal/radionuclide residues on soils and crops. However, few studies have focused on the impact of PG applications on soil biota, as well as the contribution to soils with elements in mobile fractions of PG which may affect freshwater species as well. In this context the main aim of this study was to assess the ecotoxicity of soils amended with different percentages of Tunisian phosphogypsum (0.0, 4.9, 7.4, 11.1, 16.6 and 25%) and of elutriates obtained from PG - amended soil (0.0, 6.25, 12.5 and 25% of PG) to a battery of terrestrial (Eisenia andrei, Enchytraeus crypticus, Folsomia candida, Hypoaspis aculeifer, Zea mays, Lactuca sativa) and aquatic species (Vibrio fischeri, Daphnia magna, Raphidocelis subcapitata, Lemna minor). Both for amended soils and elutriates, invertebrates (especially D. magna and E. andrei) were the most sensitive species, displaying acute (immobilization) and chronic (reproduction inhibition) effects, respectively. Despite the presence of some concerning metals in PG and elutriates (e.g., zinc and cadmium), the extremely high levels of calcium found in both test mediums, suggest that this element was the mainly responsible for the ecotoxicological effects observed. Terrestrial and aquatic plants were the most tolerant species, which is in line with studies supporting the application of PG to increase crop yields. Nevertheless, no stimulatory effects on growth were observed for any of the species tested despite the high levels of phosphorus added to soils by PG. Given the importance of soil invertebrates for several soil functions and services, this study gives rise to new serious

Decay Of Bacterial Pathogens, Fecal Indicators, And Real-Time Quantitative PCR Genetic Markers In Manure-Amended Soils

EPA Science Inventory

This study examined persistence and decay of bacterial pathogens, fecal indicator bacteria (FIB), and emerging real-time quantitative PCR (qPCR) genetic markers for rapid detection of fecal pollution in manure-amended agricultural soils. Known concentrations of transformed green...

Decay Of Bacterial Pathogen, Fecal Indicators, And Real-Time Quantitative PCR Genetic Markers In Manure Amended Soils

EPA Science Inventory

This study examined persistence and decay of bacterial pathogens, fecal indicator bacteria, and emerging real-time quantitative PCR (qPCR) genetic markers for rapid detection of fecal pollution in manre-amended agricultural soils. Known concentrations of transformed green fluore...

Greenhouse gas emissions and plant characteristics from soil cultivated with sunflower (Helianthus annuus L.) and amended with organic or inorganic fertilizers.

PubMed

López-Valdez, F; Fernández-Luqueño, F; Luna-Suárez, S; Dendooven, L

2011-12-15

Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO(2) and N(2)O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO(2) and N(2)O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N(2)O emissions but not CO(2) emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern. Copyright © 2011 Elsevier B.V. All rights reserved.

Soil solution interactions may limit Pb remediation using P amendments in an urban soil

EPA Science Inventory

Lead (Pb) contaminated soils are a potential exposure hazard to the public. Amending soils with phosphorus (P) may reduce Pb soil hazards. Soil from Cleveland, OH containing 726 ± 14 mg Pb kg^-1 was amended in a laboratory study with bone meal and triple super phospha...

Dynamics of communities of bacteria and ammonia-oxidizing microorganisms in response to simazine attenuation in agricultural soil.

PubMed

Wan, Rui; Wang, Zhao; Xie, Shuguang

2014-02-15

Autochthonous microbiota plays a crucial role in natural attenuation of s-triazine herbicides in agricultural soil. Soil microcosm study was carried out to investigate the shift in the structures of soil autochthonous microbial communities and the potential degraders associated with natural simazine attenuation. The relative abundance of soil autochthonous degraders and the structures of microbial communities were assessed using quantitative PCR (q-PCR) and terminal restriction fragment length polymorphism (TRFLP), respectively. Phylogenetic composition of bacterial community was also characterized using clone library analysis. Soil autochthonous microbiota could almost completely clean up simazine (100 mg kg(-1)) in 10 days after herbicide application, indicating a strong self-remediation potential of agricultural soil. A significant increase in the proportion of s-triazine-degrading atzC gene was found in 6 days after simazine amendment. Simazine application could alter the community structures of total bacteria and ammonia-oxidizing archaea (AOA) and bacteria (AOB). AOA were more responsive to simazine application compared to AOB and bacteria. Actinobacteria, Alphaproteobacteria and Gammaproteobacteria were the dominant bacterial groups either at the initial stage after simazine amendment or at the end stage of herbicide biodegradation, but Actinobacteria predominated at the middle stage of biodegradation. Microorganisms from several bacterial genera might be involved in simazine biodegradation. This work could add some new insights on the bioremediation of herbicides contaminated agricultural soils. Copyright © 2013 Elsevier B.V. All rights reserved.

Chemical composition of windblown dust emitted from agricultural soils amended with biosolids

NASA Astrophysics Data System (ADS)

Pi, Huawei; Sharratt, Brenton; Schillinger, William F.; Bary, Andrew; Cogger, Craig

2018-06-01

Biosolids are frequently applied to agricultural lands in dry regions, but wind erosion of these lands might transport biosolids particulates offsite and impact environmental quality. Our objective was to measure concentrations of EPA-regulated metals as well as macronutrients and micronutrients in soil and windblown sediment from a biosolids field experiment. A wind tunnel was used to generate windblown sediment from experimental plots subject to traditional (disk) or conservation (undercutter) tillage and application of biosolids or synthetic fertilizer on two measurement dates during the summer fallow phase of a winter wheat-summer fallow (WW-SF) rotation at Lind, WA in 2015 and 2016. Application of biosolids or use of undercutter tillage resulted in higher concentrations of heavy metals in the soil. For example, zinc (Zn) concentration in soil was 14% higher for undercutter than disk tillage and 21% higher for biosolids than synthetic fertilizer on the first measurement date in 2015. Differences in metal concentrations between treatments, however, were not as evident in windblown sediment. Similar results were found for nutrient concentrations in soil, but concentrations in windblown sediment were at least 10% lower for biosolids than synthetic fertilizer and undercutter than disk tillage on at least one measurement date. Little difference was found in loss of heavy metals and nutrients in windblown sediment between biosolids and synthetic fertilizer treatments. Our results suggest similar loss of metals and other elements from agriculture land after application of biosolids and synthetic fertilizer. Biosolids, however, are beneficial for increasing C and N content in soil.

Rhizosphere Environment and Labile Phosphorus Release from Organic Waste-Amended Soils.

NASA Astrophysics Data System (ADS)

Dao, Thanh H.

2015-04-01

Crop residues and biofertilizers are primary sources of nutrients for organic crop production. However, soils treated with large amounts of nutrient-enriched manure have elevated phosphorus (P) levels in regions of intensive animal agriculture. Surpluses occurred in these amended soils, resulting in large pools of exchangeable inorganic P (Pi) and enzyme-labile organic P (Po) that averaging 30.9 and 68.2 mg kg-1, respectively. Organic acids produced during crop residue decomposition can promote the complexation of counter-ions and decouple and release unbound Pi from metal and alkali metal phosphates. Animal manure and cover crop residues also contain large amounts of soluble organic matter, and likely generate similar ligands. However, a high degree of heterogeneity in P spatial distribution in such amended fields, arising from variances in substrate physical forms ranging from slurries to dried solids, composition, and diverse application methods and equipment. Distinct clusters of Pi and Po were observed, where accumulation of the latter forms was associated with high soil microbial biomass C and reduced phosphomonoesterases' activity. Accurate estimates of plant requirements and lability of soil P pools, and real-time plant and soil P sensing systems are critical considerations to optimally manage manure-derived nutrients in crop production systems. An in situ X-ray fluorescence-based approach to sensing canopy and soil XRFS-P was developed to improve the yield-soil P relationship for optimal nutrient recommendations in addition to allowing in-the-field verification of foliar P status.

Soil microbial communities as suitable bioindicators of trace metal pollution in agricultural volcanic soils

NASA Astrophysics Data System (ADS)

Parelho, Carolina; dos Santos Rodrigues, Armindo; do Carmo Barreto, Maria; Gonçalo Ferreira, Nuno; Garcia, Patrícia

2015-04-01

soil sample and quantified spectrophotometrically using a Nanodrop ND-1000. Analysis of variance (ANOVA) was carried out in order to evaluate the significant differences in SMCs activity between all soil matrices. To associate the SMCs responses to the tracers of distinct agricultural farming systems, data were further explored under Principal Component Analysis (PCA). Biomarkers responses were combined into a stress index (IBR), described by Beliaeff & Burgeot (2002). Results/Discussion: All SMCs parameters displayed significant differences between agricultural soils and reference soils, except for metabolic quotient and RNA to DNA ratio (p<0.05), revealing that SMCs are suitable bioindicators of agricultural soil quality in volcanic soils. No significant differences were found for the soil basal respiration and acid phosphatase among the farming systems, suggesting that soils amendments (a cross farming practice) are a stressing factor disrupting local SMCs activities. The PCA analysis revealed that lithium is the priority metal affecting the SMCs responses in conventional farming systems. The IBR values indicated that soils ecosystem health between farming systems are ranked as: organic (4.96) > traditional (12.94) > conventional (17.28) (the higher the value, the worse the soil health status). Conclusion: Results support the soil microbial toolbox as suitable bioindicators of metal pollution in agricultural volcanic soils, highlighting the importance of integrated biomarker-based strategies for the development of the "Trace Metal Footprint" in Andosols.

Aided Phytostabilization of Copper Contaminated Soils with L. Perenne and Mineral Sorbents as Soil Amendments

NASA Astrophysics Data System (ADS)

Radziemska, Maja

2017-09-01

The present study was designed to assess phytostabilization strategies for the treatment of soil co-contaminated by increasing levels of copper with the application mineral amendments (chalcedonite, zeolite, dolomite). From the results it will be possible to further elucidate the benefits or potential risks derived from the application of different types of mineral amendments in the remediation of a copper contaminated soil. A glasshouse pot experiment was designed to evaluate the potential use of different amendments as immobilizing agents in the aided phytostabilization of Cu-contaminated soil using ryegrass (Lolium perenne L.). The content of trace elements in plants and total in soil, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of L. perenne were significantly different in the case of applying mineral amendments to the soil, as well as increasing concentrations of copper. The greatest average above-ground biomass was observed for soil amended with chalcedonite. In this experiment, all analyzed metals accumulated predominantly in the roots of the tested plant. In general, applying mineral amendments to soil contributed to decreased levels of copper concentrations.

Degradation of phthalate and di-(2-ethylhexyl)phthalate by indigenous and inoculated microorganisms in sludge-amended soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roslev, P.; Madsen, P.L.; Thyme, J.B.

The metabolism of phthalic acid (PA) and di-(2-ethylhexyl) (DEHP) in sludge-amended agricultural soil was studied with radiotracer techniques. The initial rates of metabolism of PA and DEHP were estimated to be 731.8 and 25.6 pmol/g (dry weight) per day, respectively. Indigenous microorganisms assimilated 28 and 17% of the carbon in [{sup 14}C]PA and [{sup 14}C]DEHP, respectively, into microbial biomass. The rates of DEHP metabolism were much greater in sludge assays without soil than in assays with sludge-amended soil. Mineralization of [{sup 14}C]DEHP to {sup 14}CO{sub 2} increased fourfold after inoculation of sludge and soil samples with DEHP-degrading strain SDE 2.more » The elevated mineralization potential was maintained for more than 27 days. Experiments performed with strain SDE 2 suggested that the bioavailability and mineralization of DEHP decreased substantially in the presence of soil and sludge components. The microorganisms metabolizing PA and DEHP in sludge and sludge-amended soil were characterized by substrate-specific radiolabelling, followed by analysis of {sup 14}C-labelled phospholipid ester-linked fatty acids ({sup 14}C-PLFAs).« less

Chemical composition of windblown dust emitted from agricultural soils amended with biosolids

USDA-ARS?s Scientific Manuscript database

Biosolids are increasingly being applied to agricultural lands in dry environments, but wind erosion of these lands might transport biosolid particulates offsite and impact environmental quality. Our objective was to use a wind tunnel to measure soil and windblown sediment concentrations of EPA-regu...

Molybdenum uptake by forage crops grown on sewage sludge -- Amended soils in the field and greenhouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

McBride, M.B.; Richards, B.K.; Steenhuis, T.

2000-06-01

Molybdenum (Mo) is a plant-available element in soils that can adversely affect the health of farm animals. There is a need for more information on its uptake into forage crops from waste materials, such as sewage sludge, applied to agricultural land. Field and greenhouse experiments with several crops grown on long-term sewage sludge-amended soils as well as soils recently amended with dewatered (DW) and alkaline-stabilized (ALK) sludges indicated that Mo supplied from sludge is readily taken up by legumes in particular. Excessive uptake into red clover (Trifolium pratense L.) was seen in a soil that had been heavily amended withmore » sewage sludge 20 yr earlier, where the soil contained about 3 mg Mo/kg soil, three times the background soil concentration. The greenhouse and field studies indicated that Mo can have a long residual availability in sludge-amended soils. The effect of sludge application was to decrease Cu to Mo ratios in legume forages, canola (Brassica napus var. napus) and soybeans [Glycine max (L.) Merr.] below the recommended limit of 2:1 for ruminant diets, a consequence of high bioavailability of Mo and low uptake of Cu added in sludge. Molybdenum uptake coefficients (UCs) for ALK sludge were higher than for DW sludge, presumably due to the greater solubility of Mo measured in the more alkaline sludges and soils. Based on these UCs, it is tentatively recommended that cumulative Mo loadings on forages grown on nonacid soils should not exceed 1.0 kg/ha from ALK sludge or 4.0 kg/ha from DW sludge.« less

Assessment of Two Solid Anaerobic Digestate Soil Amendments for Effects on Soil Quality and Biosolarization Efficacy.

PubMed

Fernández-Bayo, Jesús D; Achmon, Yigal; Harrold, Duff R; McCurry, Dlinka G; Hernandez, Katie; Dahlquist-Willard, Ruth M; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

2017-05-03

Anaerobic digestion is an organic waste bioconversion process that produces biofuel and digestates. Digestates have potential to be applied as soil amendment to improve properties for crop production including phytonutrient content and pest load. Our objective was to assess the impact of solid anaerobic digestates on weed seed inactivation and soil quality upon soil biosolarization (a pest control technique that combines solar heating and amendment-induced microbial activity). Two solid digestates from thermophilic (TD) and mesophilic (MD) digesters were tested. The solarized TD-amended samples presented significantly higher mortality of Brassica nigra (71%, P = 0.032) than its equivalent incubated at room temperature. However, biosolarization with digestate amendment led to decreased weed seed mortality in certain treatments. The plant-available water, total C, and extractable P and K were significantly increased (P < 0.05) in the incubated amended soils. The results confirm the potential of digestates as beneficial soil amendments. Further studies are needed to elucidate the impacts of digestate stability on biosolarization efficacy and soil properties.

Influence of Herbicide Triasulfuron on Soil Microbial Community in an Unamended Soil and a Soil Amended with Organic Residues

PubMed Central

Pose-Juan, Eva; Igual, José M.; Sánchez-Martín, María J.; Rodríguez-Cruz, M. S.

2017-01-01

The effect of organic amendments and pesticides on a soil microbial community has garnered considerable interest due to the involvement of microorganisms in numerous soil conservation and maintenance reactions. The aim of this work was to assess the influence on a soil microbial community of the simultaneous application of the herbicide triasulfuron at three doses (2, 10, and 50 mg kg-1), with an organic amendment [sewage sludge (SS) or green compost (GC)]. Dissipation kinetics, soil microbial biomass, dehydrogenase activity (DHA) and respiration, and the profile of phospholipid fatty acids (PLFAs) extracted from the soil, were determined in unamended (S) soil and amended (S+SS and S+GC) ones. Triasulfuron dissipation followed the single first-order kinetics model. Half-life (DT50) values were higher in the amended soils than in the unamended one for the 10 and 50 mg kg-1 doses. The dissipation rates were lower in the S+GC soil for the three herbicide doses applied. In general, soil biomass, DHA and respiration values increased in SS- and GC-amended soils compared to the unamended one. DHA values decreased (S and S+SS) or increased (S+GC) with the incubation time of soil with herbicide at the different doses applied. Respiration values increased with the herbicide doses applied and decreased with the incubation time, although maximum values were obtained for soils treated with the highest dose after 70 days of incubation. PLFA analysis indicated different effects of triasulfuron on the soil microbial community structure depending on the organic amendments. While the increasing triasulfuron doses resulted in deeper alterations in the S soil, the time after triasulfuron application was the most important variation in the S+SS and S+GC soils. The overall results indicate that the soil amendment has an effect on herbicide dissipation rate and the soil microbial community. Initially, a high dose of triasulfuron had detrimental effects on the soil microbial community

Stabilization of metal(loid)s in two contaminated agricultural soils: Comparing biochar to its non-pyrolysed source material.

PubMed

Trakal, Lukáš; Raya-Moreno, Irene; Mitchell, Kerry; Beesley, Luke

2017-08-01

Two metal(loid) contaminated agricultural soils were amended with grape stalk (wine production by-product)-derived biochar as well as its pre-pyrolysed origin material, to investigate their geochemical impacts on As, Cr, Cu and Zn. Detailed physico-chemical evaluation combined with a column leaching test determined the retention of metal(loid)s from soil solution by each amendments. A pot experiment measured metal(loid)s in soil pore water and their uptake to ryegrass when the amendments were mixed into soils at 1 and 5% (w/w). Total Cr and Zn concentrations were reduced furthest in column leachates by the addition of raw material and biochar respectively, compared to the untreated soil; Cr(III) was the predominant specie initially due to rapid acidification of leachates and organic complexation resulting from raw material addition. Loadings of metal(loid)s to the amendments recovered from the post-leached columns were in the order Cu » Zn > Cr ≈ As. In the pot test ryegrass Cr uptake was initiated by the addition of both amendments, compared to the untreated soil, whereas only biochar addition resulted in significant increases in Zn uptake, explained by its significant enhancement of ryegrass biomass yield, especially at 5% dosage; raw material addition significantly decreased biomass yields. Inconsistent relationships between pore water parameters and ryegrass uptake were common to both soils investigated. Therefore, whilst both amendments modified soil metal(loid) geochemistry, their effects differed fundamentally; in environmental risk management terms these results highlight the need to investigate the detailed geochemical response of contaminated soils to diverse organic amendment additions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple storm event impacts on epikarst storage and transport of organic soil amendments in South-Central Kentucky.

USDA-ARS?s Scientific Manuscript database

The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events of winter and spring 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a known groundwater recharge area where manure wa...

Recent developments in biochar as an effective tool for agricultural soil management: a review.

PubMed

Laghari, Mahmood; Naidu, Ravi; Xiao, Bo; Hu, Zhiquan; Mirjat, Muhammad Saffar; Hu, Mian; Kandhro, Muhammad Nawaz; Chen, Zhihua; Guo, Dabin; Jogi, Qamardudin; Abudi, Zaidun Naji; Fazal, Saima

2016-12-01

In recent years biochar has been demonstrated to be a useful amendment to sequester carbon and reduce greenhouse gas emission from the soil to the atmosphere. Hence it can help to mitigate global environment change. Some studies have shown that biochar addition to agricultural soils increases crop production. The mechanisms involved are: increased soil aeration and water-holding capacity, enhanced microbial activity and plant nutrient status in soil, and alteration of some important soil chemical properties. This review provides an in-depth consideration of the production, characterization and agricultural use of different biochars. Biochar is a complex organic material and its characteristics vary with production conditions and the feedstock used. The agronomic benefits of biochar solely depend upon the use of particular types of biochar with proper field application rate under appropriate soil types and conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Soil quality and soil degradation in agricultural loess soils in Central Europe - impacts of traditional small-scale and modernized large-scale agriculture

NASA Astrophysics Data System (ADS)

Schneider, Christian

2017-04-01

The study analyzes the impact of different farming systems on soil quality and soil degradation in European loess landscapes. The analyses are based on geo-chemical soil properties, landscape metrics and geomorphological indicators. The German Middle Saxonian Loess Region represents loess landscapes whose ecological functions were shaped by land consolidation measures resulting in large-scale high-input farming systems. The Polish Proszowice Plateau is still characterized by a traditional small-scale peasant agriculture. The research areas were analyzed on different scale levels combining GIS, field, and laboratory methods. A digital terrain classification was used to identify representative catchment basins for detailed pedological studies which were focused on soil properties that responded to soil management within several years, like pH-value, total carbon (TC), total nitrogen (TN), inorganic carbon (IC), soil organic carbon (TOC=TC-IC), hot-water extractable carbon (HWC), hot-water extractable nitrogen (HWN), total phosphorus, plant-available phosphorus (P), plant-available potassium (K) and the potential cation exchange capacity (CEC). The study has shown that significant differences in major soil properties can be observed because of different fertilizer inputs and partly because of different cultivation techniques. Also the traditional system increases soil heterogeneity. Contrary to expectations the study has shown that the small-scale peasant farming system resulted in similar mean soil organic carbon and phosphorus contents like the industrialized high-input farming system. A further study could include investigations of the effects of soil amendments like herbicides and pesticide on soil degradation.

Modeling fungicides mobility in undisturbed vineyard soil cores unamended and amended with spent mushroom substrates.

PubMed

Marín-Benito, Jesús María; Rodríguez-Cruz, María Sonia; Sánchez-Martín, María Jesús; Mamy, Laure

2015-09-01

The performance of the pesticide fate model PRZM to predict the fate of two fungicides, penconazole and metalaxyl, and the major metabolite of metalaxyl (CGA-62826), in amended and unamended vineyard soils was tested from undisturbed soils columns experiments. Three different treatments were tested in two soils: control soil (unamended), and soil amended with fresh or composted spent mushroom substrates, which correspond to common agricultural practices in Spain. Leaching experiments were performed under non-saturated flow conditions. The model was parameterized with laboratory and literature data, and using pedotransfer functions. It was first calibrated for water flow against chloride breakthrough curves. The key parameter was the hydrodynamic dispersion coefficient (DISP). No leaching of penconazole, the most hydrophobic fungicide, was observed. It remained in the top 0-8 cm of the column. In any case, simulations were highly correlated to the experimental results. On the contrary, metalaxyl and its metabolite were consistently found in the leachates. A calibration step of the Kd of metalaxyl and CGA-62826 and of DISP for CGA-62826 was necessary to obtain good prediction of the leaching of both compounds. PRZM generally simulated acceptable metalaxyl vertical distribution in the soil profiles although results were overestimated for its metabolite. Nevertheless, PRZM can be reasonably used to assess the leaching (through breakthrough curves) and vertical distribution of fungicides in amended soils, knowing their DISP values. Copyright © 2015 Elsevier Ltd. All rights reserved.

Agricultural utilization of biosolids: A review on potential effects on soil and plant grown.

PubMed

Sharma, Bhavisha; Sarkar, Abhijit; Singh, Pooja; Singh, Rajeev Pratap

2017-06-01

Environmental and economic implications linked with the proper ecofriendly disposal of modern day wastes, has made it essential to come up with alternative waste management practices that reduce the environmental pressures resulting from unwise disposal of such wastes. Urban wastes like biosolids are loaded with essential plant nutrients. In this view, agricultural use of biosolids would enable recycling of these nutrients and could be a sustainable approach towards management of this hugely generated waste. Therefore biosolids i.e. sewage sludge can serve as an important resource for agricultural utilization. Biosolids are characterized by the occurrence of beneficial plant nutrients (essential elements and micro and macronutrients) which can make help them to work as an effective soil amendment, thereby minimizing the reliance on chemical fertilizers. However, biosolids might contain toxic heavy metals that may limit its usage in the cropland. Heavy metals at higher concentration than the permissible limits may lead to food chain contamination and have fatal consequences. Biosolids amendment in soil can improve physical and nutrient property of soil depending on the quantity and portion of the mixture. Hence, biosolids can be a promising soil ameliorating supplement to increase plant productivity, reduce bioavailability of heavy metals and also lead to effective waste management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Crop residue stabilization and application to agricultural and degraded soils: A review.

PubMed

Medina, Jorge; Monreal, Carlos; Barea, José Miguel; Arriagada, César; Borie, Fernando; Cornejo, Pablo

2015-08-01

Agricultural activities produce vast amounts of organic residues including straw, unmarketable or culled fruit and vegetables, post-harvest or post-processing wastes, clippings and residuals from forestry or pruning operations, and animal manure. Improper disposal of these materials may produce undesirable environmental (e.g. odors or insect refuges) and health impacts. On the other hand, agricultural residues are of interest to various industries and sectors of the economy due to their energy content (i.e., for combustion), their potential use as feedstock to produce biofuels and/or fine chemicals, or as a soil amendments for polluted or degraded soils when composted. Our objective is review new biotechnologies that could be used to manage these residues for land application and remediation of contaminated and eroded soils. Bibliographic information is complemented through a comprehensive review of the physico-chemical fundamental mechanisms involved in the transformation and stabilization of organic matter by biotic and abiotic soil components. Copyright © 2015 Elsevier Ltd. All rights reserved.

Soil management of copper mine tailing soils--sludge amendment and tree vegetation could improve biological soil quality.

PubMed

Asensio, Verónica; Covelo, Emma F; Kandeler, Ellen

2013-07-01

Mine soils at the depleted copper mine in Touro (Northwest Spain) are physico-chemically degraded and polluted by chromium and copper. To increase the quality of these soils, some areas at this mine have been vegetated with eucalyptus or pines, amended with sludges, or received both treatments. Four sites were selected at the Touro mine tailing in order to evaluate the effect of these different reclamation treatments on the biological soil quality: (1) Control (untreated), (2) Forest (vegetated), (3) Sludge (amended with sludges) and (4) Forest+Sludge (vegetated and amended). The new approach of the present work is that we evaluated the effect of planting trees or/and amending with sludges on the biological soil quality of mine sites polluted by metals under field conditions. The addition of sludges to mine sites recovered the biological quality of the soil, while vegetating with trees did not increase microbial biomass and function to the level of unpolluted sites. Moreover, amending with sludges increased the efficiency of the soil's microbial community to metabolize C and N, which was indicated by the decrease of the specific enzyme activities and the increase in the ratio Cmic:Nmic (shift towards predominance of fungi instead of bacteria). However, the high Cu and Cr concentrations still have negative influence on the microorganisms in all the treated soils. For the future remediation of mine soils, we recommend periodically adding sludge and planting native legume species. Copyright © 2013 Elsevier B.V. All rights reserved.

Chloropicrin Emission Reduction by Soil Amendment with Biochar

PubMed Central

Wang, Qiuxia; Yan, Dongdong; Liu, Pengfei; Mao, Liangang; Wang, Dong; Fang, Wensheng; Li, Yuan; Ouyang, Canbin; Guo, Meixia; Cao, Aocheng

2015-01-01

Biochar has sorption capacity, and can be used to enhance the sequestration of volatile organic contaminants such as pesticides in soil. Chloropicrin (CP) is an important soil fumigant for the production of many fruit and vegetable crops, but its emissions must be minimized to reduce exposure risks and air pollution. The objective of this study was to determine the capacity of biochar to adsorb CP and the effect of biochar amendments to soil on CP emission, concentration in the soil gas phase, degradation in soil and CP bioactivity for controlling soil borne pests. CP emission and concentration in the soil air phase were measured from packed soil columns after fumigant injection at 20-cm depth and application of selected doses of biocharto the surface 5 cm soil. Laboratory incubation and fumigation experiments were conducted to determine the capacity of biochar to adsorb CP, the effects on CP degradation and, separately, CP’s bioactivity on soil borne pests in soil amended with biochar. Biochar amendment at 2% to 5% (w/w) greatly reduced total CP emission losses by 85.7% - 97.7% compared to fumigation without biochar. CP concentrations in the soil gas-phase, especially in the top 5 cm of soil, were reduced within 48 h following application. The half-life of CP decreased from 13.6 h to 6.4 h as the biochar rate increased from 0% to 5%. CP and its metabolite (dichloronitromethane) both degraded more rapidly in pure biochar than in soil. The biochar used in the present study had a maximum adsorption capacity for CP of less than 5 mg g-1. There were no negative effects on pathogen and nematode control when the biochar used in this study was less than 1% (on a weight basis) in soil. Biochar amendment to soil reduced the emissions of CP. CP concentrations in the top 5 cm of soil gas-phase were reduced. CP degradation was accelerated with the addition of biochar. The biochar used in the present study had a low adsorption capacity for CP. There were no negative effects

Evaluation of soil amendments as a remediation alternative for cadmium-contaminated soils under cacao plantations.

PubMed

Chavez, E; He, Z L; Stoffella, P J; Mylavarapu, R; Li, Y; Baligar, V C

2016-09-01

Elevated plant-available cadmium (Cd) in soils results in contamination to cacao (Theobroma cacao L) beans. Effectiveness of vermicompost and zeolite in reducing available Cd in three cacao-growing soils was studied under laboratory conditions. Sorption-desorption experiments were conducted in soils and amendments. Cadmium was added at 0 or 5 mg kg(-1) (spiked), then, amendments were incorporated at 0, 0.5, or 2 %. Amended soils were incubated at room temperature for 28 days. Plant-available Cd was determined using 0.01 M CaCl2 (WSE) and Mehlich 3 (M3) extraction procedures in subsamples taken from individual bags at six time intervals. Soils and amendments displayed different sorption characteristics and a better fit was attained with Freundlich model (R (2) > 0.82). Amendments were ineffective in reducing extractable Cd in non-spiked soils. In Cd-spiked soils, vermicompost at 2 % significantly reduced WSE-Cd (P < 0.01) from 3.36, 0.54, and 0.38 mg kg(-1) to values lower that instrument's detection in all the three soils and significantly diminished M3-extractable Cd (P < 0.05) from 4.62 to 4.11 mg kg(-1) in only one soil. Vermicompost at 0.5 % significantly decreased WSE-Cd (P < 0.01) from 3.04 and 0.31 to 1.69 and 0.20 mg kg(-1), respectively, in two soils with low sorption capacity for Cd. In contrast, zeolite failed to reduce WSE- or M3-extractable Cd in all studied soils. A negative correlation occurred between soil pH and WSE-Cd (r > -0.89, P < 0.01). The decrease in WSE-Cd appears to be associated with the increase in pH of the vermicompost-amended soils.

Effects of biochar amendment on geotechnical properties of landfill cover soil.

PubMed

Reddy, Krishna R; Yaghoubi, Poupak; Yukselen-Aksoy, Yeliz

2015-06-01

Biochar is a carbon-rich product obtained when plant-based biomass is heated in a closed container with little or no available oxygen. Biochar-amended soil has the potential to serve as a landfill cover material that can oxidise methane emissions for two reasons: biochar amendment can increase the methane retention time and also enhance the biological activity that can promote the methanotrophic oxidation of methane. Hydraulic conductivity, compressibility and shear strength are the most important geotechnical properties that are required for the design of effective and stable landfill cover systems, but no studies have been reported on these properties for biochar-amended landfill cover soils. This article presents physicochemical and geotechnical properties of a biochar, a landfill cover soil and biochar-amended soils. Specifically, the effects of amending 5%, 10% and 20% biochar (of different particle sizes as produced, size-20 and size-40) to soil on its physicochemical properties, such as moisture content, organic content, specific gravity and pH, as well as geotechnical properties, such as hydraulic conductivity, compressibility and shear strength, were determined from laboratory testing. Soil or biochar samples were prepared by mixing them with 20% deionised water based on dry weight. Samples of soil amended with 5%, 10% and 20% biochar (w/w) as-is or of different select sizes, were also prepared at 20% initial moisture content. The results show that the hydraulic conductivity of the soil increases, compressibility of the soil decreases and shear strength of the soil increases with an increase in the biochar amendment, and with a decrease in biochar particle size. Overall, the study revealed that biochar-amended soils can possess excellent geotechnical properties to serve as stable landfill cover materials. © The Author(s) 2015.

Natural attenuation of toxic metal phytoavailability in 35-year-old sewage sludge-amended soil.

PubMed

Tai, Yiping; Li, Zhian; Mcbride, Murray B

2016-04-01

Toxic heavy metals persist in agricultural soils and ecosystem for many decades after their application as contaminants in sewage sludge and fertilizer products This study assessed the potential long-term risk of cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu) in land-applied sewage sludge to food crop contamination. A sewage sludge-amended soil (SAS) aged in the field more than 35 years was used in a greenhouse pot experiment with leafy vegetables (lettuce and amaranth) having strong Cd and Zn accumulation tendencies. Soil media with variable levels of available Cd, Zn, and Cu (measured using 0.01 M CaCl2 extraction) were prepared by diluting SAS with several levels of uncontaminated control soil. Despite long-term aging in the field, the sludge site soil still retains large reserves of heavy metals, residual organic matter, phosphorus, and other nutrients, but its characteristics appear to have stabilized over time. Nevertheless, lettuce and amaranth harvested from the sludge-treated soil had undesirable contents of Cd and Zn. The high plant uptake efficiency for Cd and Zn raises a concern regarding the quality and safety of leafy vegetables in particular, when these crops are grown on soils that have been amended heavily with sewage sludge products at any time in their past.

Responses of soil biota to organic amendments in stripmine spoils in Northwestern New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elkins, N.Z.; Parker, L.W.; Aldon, E.

The effects of organic amendments and topsoiling on the soil biota and decomposition were examined in order to evaluate the relative efficacy of the amendments in restarting soil processes. Decomposition of barley straw (Hordeum vulgare) and populations of soil biota on strip coal-mine spoils in northwestern New Mexico were studied. The spoils had been amended with straw mulch, bark, topsoil, or no organic additives. Decomposition rates were highest in the unmined area and the bark, amended spoils, and lowest on the topsoil amendment and unamended spoil. Few differences were observed in the populations of soil microflora. Where differences were observed,more » the bark-amended spoils had the highest populations and biomass. Soil microflora activity, as indicated by decomposition rates, was enhanced by bark amendment. Soil microfaunal populations were highest on the bark-amended spoils and unmined soil. Important soil mites (soil Acari), the oribatids, were found only in the bark-amended spoils and the unmined soils. These studies suggest that addition of selected organic amendments (bark) to mine spoils may be as effective in developing a soil as the more expensive topsoil/mulch procedures currently used in reclamation procedures. 25 references.« less

Effects of poultry manure, compost, and biochar amendments on soil nitrogen dynamics in maize production systems

NASA Astrophysics Data System (ADS)

Ryals, R.; Tang, J.; Hastings, M. G.; Dell, C. J.; Sims, T.

2013-12-01

Intensification of animal agriculture has profound impacts on the global and local biogeochemistry of nitrogen (N), resulting in consequences to environmental and human health. In the Chesapeake Bay watershed, intensive agriculture is the primary contributor to N pollution, with animal manure comprising more than half of N from agriculture. Management interventions may play an important role in mitigating reactive N pollution in the Bay watershed. The objective of our research was to test management strategies that maximize benefits of poultry manure as an agricultural resource while minimizing it as a source of reactive nitrogen to the atmosphere and ground and surface waters. We conducted field experiments in two agricultural regions of the Chesapeake Bay watershed (Georgetown, Delaware and State College, Pennsylvania) to explore the effects of poultry manure amendments on gaseous N losses and soil N transformations. Treatments were applied at rates needed to meet the plant N demand at each site and included unfertilized controls, fertilizer N (urea), and raw, composted, or and biocharred poultry manure. The fate of the N from all sources was followed throughout the growing season. Global greenhouse gases emitted from soil (nitrous oxide [N2O] and carbon dioxide [CO2]) and regional air pollutants (nitrogen oxides [NOx] and ammonia [NH3]) were measured. Gas measurements were coupled with data on treatment effects on temperature, moisture, and concentrations of nitrate (NO3¬-) and ammonium (NH4+) in surface soils (0-10 cm). Soil NO3- and NH4+ were also measured approximately monthly in the soil profile (0-10, 10-30, 30-50, 50-70, and 70-100 cm) as an index of leaching potential. Plant N uptake and grain production were also quantified to quantify crop N use efficiency and compare measured N losses for each N source. Our results suggest that the form of poultry manure amendments can affect the magnitude of reactive N losses to the environment.

Degradation of dimethyl disulphide in soil with or without biochar amendment.

PubMed

Han, Dawei; Yan, Dongdong; Cao, Aocheng; Fang, Wensheng; Liu, Pengfei; Li, Yuan; Ouyang, Canbin; Wang, Qiuxia

2017-09-01

Dimethyl disulphide (DMDS) is a new and effective alternative to methyl bromide for soil fumigation. The effect of biochar on the fate of DMDS in soil is not fully understood. The objective of this study was to determine the degradation kinetics of DMDS in different soils and evaluate the effect of biochar amendment on DMDS degradation using incubation experiments. The degradation half-life of DMDS was between 1.05 and 6.66 days under non-sterile conditions, and 12.63 to 22.67 days under sterile conditions in five types of soil. Seven out of the eight tested biochar amendments (BC-2 to BC-8) delayed the degradation of DMDS in soil, increasing the half-life of DMDS in Fangshan soil from 1.05 to 1.16-5.87 days following amendment with 1% (w/w) biochar. The degradation rate of DMDS in Fangshan soil accelerated as the amendment rate of BC-1 increased, and decreased as the amendment rate of BC-7 increased. Biodegradation is an important degradation route for DMDS in soil, and DMDS degraded faster in alkaline soil. The effects of biochar amendments on DMDS degradation in soil are determined by complex multiple factors (such as surface area, pH and physicochemical composition), rather than by any single property of biochar. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Amending soils with sediment material from constructed wetlands increases phosphorus sorption

NASA Astrophysics Data System (ADS)

Laakso, Johanna; Uusitalo, Risto; Leppänen, Janette; Yli-Halla, Markku

2017-04-01

Sediment of agricultural constructed wetlands (CWs) is comprised of matter eroded from surrounding fields. This material is rich in aluminium (Al) and iron (Fe) (hydr)oxides that have a high affinity for phosphorus (P). Sediment material returned to fields could therefore affect soil P retention characteristics. We incubated a clay soil with a high soil test P (STP, 24 mg PAc l-1; extracted with pH 4.65 ammonium acetate buffer) and a sandy loam with excessive STP (210 mg PAc l-1) for three weeks with increasing amounts of CW sediment: 0, 2, 5, 10 and 50% of the sample volume. After incubation, the soil-sediment mixtures were studied with the quantity/intensity (Q/I) technique, using chemical extractions and by exposing the mixtures to simulated rainfall. Sorption affinity for P regularly increased with increasing the sediment share of the mixtures, the 0% sediment content having the lowest and 50% sediment content the highest P sorption. With 0% sediment application, the value of equilibrium P concentration (EPC0) determined by Q/I technique, was 0.69 and 44.3 mg l-1 for clay soil and sandy loam, respectively. With 2-5% sediment amendment, the EPC0 decreased 13-36% for clay soil and 13-54% for sandy loam. The 50% sediment mixtures had EPC0 of 0.05 mg l-1 for both soils. At a practically feasible sediment addition rate of 5%, dissolved reactive P (DRP) in percolating water from simulated rainfall decreased by 55% in the clay soil and 54% in sandy loam (p<0.001 in both cases). Particulate-P (PP) also showed a decreasing trend with increasing sediment addition rate. Upon prolonged simulated rainfall, the decreasing effect of sediment on DRP and PP declined somewhat. The effects of sediment addition can be attributed partly to increased salt concentrations in the sediment, which have a short-term effect on P mobilisation, but mostly to increased concentrations of Al and Fe (hydr)oxides, increasing long-term P sorption capacity. Amending the soils with sediment material

Dissolved organic C and N pools in soils amended with composted and thermally-dried sludge as affected by soil tillage systems and sampling depth

NASA Astrophysics Data System (ADS)

García-Gil, Juan Carlos; Soler-Rovira, Pedro Angel; García López de Sa, Esther; Polo, Alfredo

2013-04-01

Soil tillage practices exert a significant influence on the dynamic of soluble organic C and N pools, affecting nutrient cycling in agricultural systems by enhancing its mineralization through microbial activities or stabilization in soil microaggregates, which contribute to mitigate greenhouse gases emissions. The objective of the present research was to determine the influence of three different soil management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) obtained from wastewater treatment processes on dissolved organic C (water-soluble organic C -WSOC-, carbohydrates, phenolic compounds) and soluble N (total-N, NH4+, NO3-) pools in a long-term field experiment (27 years) conducted on a sandy-loam soil at the experimental station "La Higueruela" (40° 03'N, 4° 24'W) under semi-arid conditions. Both organic amendments were applied at a rate of 30 tonnes per hectare prior to tillage practices. Unamended soils were used as control for each tillage system. Soil sampling was performed two months after tillage practices at the following depths for each treatment: 0-10 cm, 10-20 cm and 20-30 cm. Results obtained for unamended soils showed that no-tillage management increased total-N, NH4+ and NO3- contents at the 0-10 cm depth samples, meanwhile WSC and carbohydrates contents were larger at 20-30 cm depth samples in both moldboard and no-tillage plots. CS and TSS-amended soils presented a general increase in soluble C and N compounds, being significantly higher in TSS-amended soils, as TSS contains a great amount of labile organic C and N substrates due to the lack of stabilization treatment. TSS-amended soils under no-tillage and chisel plowing showed larger N, NH4+ and NO3- content at the 0-10 cm samples, meanwhile moldboard management exhibited larger NH4+ and NO3- content at 10-20 and 20-30 cm samples, possibly due to the incorporation of TSS at deeper depths (20-40 cm). CS

Behavior of oxyfluorfen in soils amended with different sources of organic matter. Effects on soil biology.

PubMed

Gómez, Isidoro; Rodríguez-Morgado, Bruno; Parrado, Juan; García, Carlos; Hernández, Teresa; Tejada, Manuel

2014-05-30

We performed a laboratory study on the effect of oxyfluorfen at a rate of 4lha(-1) on biological properties of a soil amended with four organic wastes (two biostimulants/biofertilizers, obtained from rice bran, RB1 and RB2; municipal solid waste, MSW; and sheep manure, SM). Soil was mixed with SM at a rate of 1%, MSW at a rate of 0.52%, RB1 at a rate of 0.39% and RB2 at a rate of 0.30%, in order to apply the same amount of organic matter to the soil. The enzymatic activities and microbial community in the soil were determined during the incubation times. The application of RB1 and RB2 to soil without oxyfluorfen increased the enzymatic activities and biodiversity, peaking at day 10 of the incubation period. This stimulation was higher in the soil amended with RB2 than in that amended with RB1. In SM and CF-amended soils, the stimulation of enzymatic activities and soil biodiversity increased during the experiment. The application of herbicide in organic-amended soils decreased the inhibition of soil enzymatic activities and soil biodiversity. Possibly the low molecular weight protein content easily assimilated by soil microorganisms and the higher fat content in the biostimulants/biofertilizers are responsible for the lower inhibition of these soil biological properties. Copyright © 2014 Elsevier B.V. All rights reserved.

Soil amino compound and carbohydrate contents influenced by organic amendments

USDA-ARS?s Scientific Manuscript database

Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

Achilles heel of environmental risk from recycling of sludge to soil as amendment: A summary in recent ten years (2007-2016).

PubMed

Liu, Hong-Tao

2016-10-01

Recycling sludge as a soil amendment has both positive and negative effects because of its enrichment in both nutrients and contaminants. So far, the negative effect has to be extensively investigated that the severities of different types of contaminants also remain unclear. The environmental behavior and risk of organic contaminant and pharmaceuticals, heavy metal and salt as well as pathogenic microorganisms brought by sludge amendment are summarized and discussed here. Organic contaminants and pharmaceuticals are typically found at low concentrations in sludge, the risks from sludge-amended soil decrease over time owing to its biodegradability. On the other hand, application of sludge generally increases soil salinity, which may cause physiological damage to plants grown in sludge-amended soil. In some extent, this negative effect can be alleviated by means of dilution; however, greater attention should be paid to long term increasing possible risk of eutrophication. Heavy metal (particularly of mobile heavy metals, such as Cd) with high concentrations in sludge and soil receiving considerable sludge can cause its incremental abundance in soil and crop contamination, further posing risks to humans, but most cases showed that there remained not excessive in heavy metal caused by sludge amendment. It is worth noting that increasing soil organic matter content may reduce transfer of heavy metal from soil to crops, but not restrict its uptake by crops at all. Combined literature together, it is summarized that heavy metal becomes a relatively severe bottleneck in recycling of sludge as soil amendment due to its non-biodegradability and potential damage to health by adventuring contamination from agricultural products. Particular attention should therefore be paid to long term monitoring the change of heavy metals concentration in sludge amended soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bioavailability Of Arsenic In Arsenical Pesticide-Amended Soils: Preliminary Greenhouse Study

NASA Astrophysics Data System (ADS)

Quazi, S.; Sarkar, D.; Khairom, A.; Datta, R.; Sharma, S.

2005-05-01

Long-term application of arsenical pesticides in agricultural lands has resulted in high levels of arsenic (As). Conversion of former agricultural lands to residential areas has resulted in increased human contact with soil As. Soil ingestion from incidental hand-to-mouth activity by children is now a very important issue in assessing human health risk associated with exposure to arsenical pesticide-applied former agricultural soils. Human health risk from direct exposure to soil As via hand to mouth action is restricted only to those fractions of As in the soil that are available to the human gastrointestinal system. Thus this study aimed at addressing the issue of soil variability on As bioavailability as a function of soil physiochemical properties in a dynamic interaction between soils, water and plants and pesticides. In the current greenhouse study two soils with drastically different chemical characteristics w.r.t As reactivity (Immokalee-low As retention potential and Millhopper-high As retention potential) and one pesticide (sodium arsenate) were used. Soils were amended with sodium arsenate at two rates representing the high and low ends of As contamination, generally representative of Superfunds site conditions: 675 and 1500 mg/kg As. Rice (Oryza sativa) was used as the test crop. Sequential digestion to estimate in-vitro As in the stomach phase and the intestinal phase was employed on soils sampled at 4 times: 0-time, after 3 mo, 6 mo and 9 mo of soil-pesticide equilibration. In-vitro bioavailability experiments were also performed with the same soils in order to obtain an estimate of the amount of As that would be absorbed to the intestinal linings in simulated systems. Following the greenhouse study, selective in-vivo bioavailability studies using As-contaminated soils will be conducted on male and female mice to correlate in-vitro results with the in-vivo data. Treatments will consist of a soil group (As in soil), a positive control group (only As

Fuzzy indicator approach: development of impact factor of soil amendments

USDA-ARS?s Scientific Manuscript database

Soil amendments have been shown to be useful for improving soil condition, but it is often difficult to make management decisions as to their usefulness. Utilization of Fuzzy Set Theory is a promising method for decision support associated with utilization of soil amendments. In this article a tool ...

Effectiveness of T. harzianum and Humate Amendment in Soil Salinity Restoration

NASA Astrophysics Data System (ADS)

Apostolakis, Antonios; Daliakopoulos, Ioannis; Tsanis, Ioannis

2017-04-01

Soil salinity is a major soil degradation threat, especially for the water stressed parts of the Mediterranean region, where it hinders soil fertility and thus agricultural productivity. Soil salinity management can be complex and expensive, often resorting to the use of chemical amendments thus risking soil and aquifer pollution. This study quantifies the beneficial effects of (a) a commercial strain of the beneficial fungus Trichoderma harzianum (TH), and (b) a commercial humate fertilizer enhancer (HFE) approved for organic farming, against soil salinization. The treatments are tested in the context of a Solanum lycopersicum (tomato) greenhouse simulation of the cultivation conditions typical for the semi-arid coastal Timpaki basin in south-central Crete. 20 vigorous 20-day-old Solanum lycopersicum L. cv Elpida seedlings are treated either with TH or HFE, using soil substrates and irrigation treatments of two degradation states. 20 additional plants serve either as controls or guard rows. All plants are transplanted into 35 L pots under greenhouse conditions. Preliminary analysis of soil salinity and crop yield indicators suggest that both treatments are beneficial for the soil-plant system, each to a different extent depending on initial soil conditions.

Effect of pyrochar and hydrochar amendments on the mineralization of the herbicide isoproturon in an agricultural soil.

PubMed

Eibisch, Nina; Schroll, Reiner; Fuß, Roland

2015-09-01

Carbon (C)-rich, solid products from pyrolysis (pyrochars) and hydrothermal carbonization (HTC, hydrochars) are expected to reduce the bioavailability and bioaccessibility of pesticides as side effect of soil addition. To compare effects of different feedstocks (digestate, miscanthus, woodchips) and production processes (pyrolysis at 750°C, HTC at 200°C and 250°C), (14)C-labeled isoproturon (IPU) was applied at 0.75 kg ha(-)(1) to loamy sand amended either with 0.5% or 5% pyrochars or hydrochars, which was then incubated for 50d. Mineralization of IPU was measured as (14)C-CO2 released from soil-char composites. Pore-water and methanol extractable (14)C-IPU was quantified as well as non-extractable (14)C-residues (NER). Furthermore, C mineralization of pyrochars, hydrochars and feedstocks was studied to assess the relationship between IPU bioaccessibility and char decomposability. In pure soil, 8.1% of applied IPU was mineralized after 50d. This was reduced more strongly in pyrochar treatments (81 ± 6% reduction) than in hydrochar treatments (56 ± 25% reduction). Different feedstocks had no significantly different effect when 5% char was added, but their effect was significant and dependent on the production process in 0.5% amendments. Pesticide binding can occur by surface sorption as well as by diffusion and subsequent occlusion in micropores. The latter can be expected to result in high amounts of NER, as it was observed in the pyrochar treatments. Hydrochars were less stable than pyrochars and contained lower amounts of NER. Thus, in hydrochar amended soils, better accessibility of IPU to microbial degradation may be a result of full char decomposition within decades ensuring controlled pesticide degradation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Particulate matter emissions from biochar-amended soils as a potential tradeoff to the negative emission potential

NASA Astrophysics Data System (ADS)

Ravi, Sujith; Sharratt, Brenton S.; Li, Junran; Olshevski, Stuart; Meng, Zhongju; Zhang, Jianguo

2016-10-01

Novel carbon sequestration strategies such as large-scale land application of biochar may provide sustainable pathways to increase the terrestrial storage of carbon. Biochar has a long residence time in the soil and hence comprehensive studies are urgently needed to quantify the environmental impacts of large-scale biochar application. In particular, black carbon emissions from soils amended with biochar may counteract the negative emission potential due to the impacts on air quality, climate, and biogeochemical cycles. We investigated, using wind tunnel experiments, the particulate matter emission potential of a sand and two agriculturally important soils amended with different concentrations of biochar, in comparison to control soils. Our results indicate that biochar application considerably increases particulate emissions possibly by two mechanisms-the accelerated emission of fine biochar particles and the generation and emission of fine biochar particles resulting from abrasion of large biochar particles by sand grains. Our study highlights the importance of considering the background soil properties (e.g., texture) and geomorphological processes (e.g., aeolian transport) for biochar-based carbon sequestration programs.

Impact of long-term organic residue recycling in agriculture on soil solution composition and trace metal leaching in soils.

PubMed

Cambier, Philippe; Pot, Valérie; Mercier, Vincent; Michaud, Aurélia; Benoit, Pierre; Revallier, Agathe; Houot, Sabine

2014-11-15

Recycling composted organic residues in agriculture can reduce the need of mineral fertilizers and improve the physicochemical and biological properties of cultivated soils. However, some trace elements may accumulate in soils following repeated applications and impact other compartments of the agrosystems. This study aims at evaluating the long-term impact of such practices on the composition of soil leaching water, especially on trace metal concentrations. The field experiment QualiAgro started in 1998 on typical loess Luvisol of the Paris Basin, with a maize-wheat crop succession and five modalities: spreading of three different urban waste composts, farmyard manure (FYM), and no organic amendment (CTR). Inputs of trace metals have been close to regulatory limits, but supplies of organic matter and nitrogen overpassed common practices. Soil solutions were collected from wick lysimeters at 45 and 100 cm in one plot for each modality, during two drainage periods after the last spreading. Despite wide temporal variations, a significant effect of treatments on major solutes appears at 45 cm: DOC, Ca, K, Mg, Na, nitrate, sulphate and chloride concentrations were higher in most amended plots compared to CTR. Cu concentrations were also significantly higher in leachates of amended plots compared to CTR, whereas no clear effect emerged for Zn. The influence of amendments on solute concentrations appeared weaker at 1 m than at 45 cm, but still significant and positive for major anions and DOC. Average concentrations of Cu and Zn at 1m depth lied in the ranges [2.5; 3.8] and [2.5; 10.5 μg/L], respectively, with values slightly higher for plots amended with sewage sludge compost or FYM than for CTR. However, leaching of both metals was less than 1% of their respective inputs through organic amendments. For Cd, most values were <0.05 μg/L. So, metals added through spreading of compost or manure during 14 years may have increased metal concentrations in leachates of

Nitrate capture and slow release in biochar amended compost and soil.

PubMed

Hagemann, Nikolas; Kammann, Claudia I; Schmidt, Hans-Peter; Kappler, Andreas; Behrens, Sebastian

2017-01-01

Slow release of nitrate by charred organic matter used as a soil amendment (i.e. biochar) was recently suggested as potential mechanism of nutrient delivery to plants which may explain some agronomic benefits of biochar. So far, isolated soil-aged and composted biochar particles were shown to release considerable amounts of nitrate only in extended (>1 h) extractions ("slow release"). In this study, we quantified nitrate and ammonium release by biochar-amended soil and compost during up to 167 h of repeated extractions in up to six consecutive steps to determine the effect of biochar on the overall mineral nitrogen retention. We used composts produced from mixed manures amended with three contrasting biochars prior to aerobic composting and a loamy soil that was amended with biochar three years prior to analysis and compared both to non-biochar amended controls. Composts were extracted with 2 M KCl at 22°C and 65°C, after sterilization, after treatment with H2O2, after removing biochar particles or without any modification. Soils were extracted with 2 M KCl at 22°C. Ammonium was continuously released during the extractions, independent of biochar amendment and is probably the result of abiotic ammonification. For the pure compost, nitrate extraction was complete after 1 h, while from biochar-amended composts, up to 30% of total nitrate extracted was only released during subsequent extraction steps. The loamy soil released 70% of its total nitrate amount in subsequent extractions, the biochar-amended soil 58%. However, biochar amendment doubled the amount of total extractable nitrate. Thus, biochar nitrate capture can be a relevant contribution to the overall nitrate retention in agroecosystems. Our results also indicate that the total nitrate amount in biochar amended soils and composts may frequently be underestimated. Furthermore, biochars could prevent nitrate loss from agroecosystems and may be developed into slow-release fertilizers to reduce global N

Nitrate capture and slow release in biochar amended compost and soil

PubMed Central

Kammann, Claudia I.; Schmidt, Hans-Peter; Kappler, Andreas; Behrens, Sebastian

2017-01-01

Slow release of nitrate by charred organic matter used as a soil amendment (i.e. biochar) was recently suggested as potential mechanism of nutrient delivery to plants which may explain some agronomic benefits of biochar. So far, isolated soil-aged and composted biochar particles were shown to release considerable amounts of nitrate only in extended (>1 h) extractions (“slow release”). In this study, we quantified nitrate and ammonium release by biochar-amended soil and compost during up to 167 h of repeated extractions in up to six consecutive steps to determine the effect of biochar on the overall mineral nitrogen retention. We used composts produced from mixed manures amended with three contrasting biochars prior to aerobic composting and a loamy soil that was amended with biochar three years prior to analysis and compared both to non-biochar amended controls. Composts were extracted with 2 M KCl at 22°C and 65°C, after sterilization, after treatment with H2O2, after removing biochar particles or without any modification. Soils were extracted with 2 M KCl at 22°C. Ammonium was continuously released during the extractions, independent of biochar amendment and is probably the result of abiotic ammonification. For the pure compost, nitrate extraction was complete after 1 h, while from biochar-amended composts, up to 30% of total nitrate extracted was only released during subsequent extraction steps. The loamy soil released 70% of its total nitrate amount in subsequent extractions, the biochar-amended soil 58%. However, biochar amendment doubled the amount of total extractable nitrate. Thus, biochar nitrate capture can be a relevant contribution to the overall nitrate retention in agroecosystems. Our results also indicate that the total nitrate amount in biochar amended soils and composts may frequently be underestimated. Furthermore, biochars could prevent nitrate loss from agroecosystems and may be developed into slow-release fertilizers to reduce global N

Isolation and evaluation of potent Pseudomonas species for bioremediation of phorate in amended soil.

PubMed

Jariyal, Monu; Gupta, V K; Jindal, Vikas; Mandal, Kousik

2015-12-01

Use of phorate as a broad spectrum pesticide in agricultural crops is finding disfavor due to persistence of both the principal compound as well as its toxic residues in soil. Three phorate utilizing bacterial species (Pseudomonas sp. strain Imbl 4.3, Pseudomonas sp. strain Imbl 5.1, Pseudomonas sp. strain Imbl 5.2) were isolated from field soils. Comparative phorate degradation analysis of these species in liquid cultures identified Pseudomonas sp. strain Imbl 5.1 to cause complete metabolization of phorate during seven days as compared to the other two species in 13 days. In soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil), Pseudomonas sp. strain Imbl 5.1 resulted in active metabolization of phorate by between 94.66% and 95.62% establishing the same to be a potent bacterium for significantly relieving soil from phorate residues. Metabolization of phorate to these phorate residues did not follow the first order kinetics. This study proves that Pseudomonas sp. strain Imbl 5.1 has huge potential for active bioremediation of phorate both in liquid cultures and agricultural soils. Copyright © 2015 Elsevier Inc. All rights reserved.

Carbon dynamics of contrasting agricultural practices

NASA Astrophysics Data System (ADS)

Ghee, Claire; Hallett, Paul; Neilson, Roy; Robinson, David; Paterson, Eric

2013-04-01

Application of organic amendments can improve soil quality and provide crop nutrients. To optimise these agricultural benefits from organic applications, the capacity of microbe-driven nutrient and carbon cycling must be understood and exploited. Consideration is therefore required of the complex interactions between the rhizosphere, microbial biomass and organic amendment. We hypothesise that the labile C present in root exudates of plants increases the mineralisation of organic matter in soil, constituting a mechanism to promote nutrient acquisition. This mechanism is known as the 'priming effect', but is poorly understood in the context of agricultural carbon and nutrient management. Field data from the Centre of Sustainable Cropping (CSC) research platform (Dundee, Scotland, UK) are utilised to build an understanding of soil C and N fluxes between contrasting agricultural practices. The field site uses a split-plot design to compare (i) compost amended soils with reduced tillage and chemical inputs and (ii) conventionally managed soils, reflective of current UK commercial arable practice. Significant differences (p= <0.001) were identified between compost amended and conventionally managed soils at field-scale with respect to soil microbial biomass (SMB), total organic carbon (TOC) and mineral nitrogen. Investigation into the priming effect within compost amended soils was subsequently undertaken under laboratory conditions. Stable isotope analysis and measurements of soil biotic parameters were used to quantify priming resulting from Spring Barley (Hordeum vulgare cv. Optic) cultivation for (i) unamended and (ii) municipal compost incorporated soils. Compost treatments comprised amendments of 25, 50 and 150 t/Ha and planted soils were compared with unplanted controls. Soil mesocosms were maintained under controlled environmental conditions within labelling chambers supplied continuously with 13C-depleted CO2. Throughout a 41-day incubation period, soil CO2

Heavy metals content in degraded agricultural soils of a mountain region related to soil properties

NASA Astrophysics Data System (ADS)

Navarro-Pedreño, José; Belén Almendro-Candel, María; Gómez, Ignacio; Jordán, Manuel M.; Bech, Jaume; Zorpas, Antonis

2017-04-01

Agriculture has been practiced for long time in Mediterranean regions. Intensive agriculture and irrigation have developed mainly in the valleys and coastal areas. In the mountainous areas, dry farming has been practiced for centuries. Soils have been fertilized using mainly organic amendments. Plants extracted nutrients and other elements like heavy metals presented in soils and agricultural practices modified soil properties that could favor the presence of heavy metals. In this work, it has been checked the content of heavy metals in 100 agricultural soils samples of the NorthWest area of the province of Alicante (Spain) which has been long cultivated with cereals and olive trees, and now soils are abandoned and degraded because of the low agricultural yields. European policy has the aim to improve the sustainable agriculture and recover landscapes of mountain regions. So that, it is important to check the state of the soils (Marques et al. 2007). Soils samples (arable layer) were analyzed determining: pH (1:5, w/v, water extract), equivalent calcium carbonate content, organic matter by Walkley-Black method (Nelson and Sommers 1996), micronutrients (Cu, Fe, Mn, Zn) extracted with DTPA (Lindsay and Norvell, 1978) and measured by atomic absorption spectrometry, and total content of metals (Cd, Cr, Ni, Pb) measured in soil samples after microwave acid digestion (Moral et al. 1996), quantifying the content of metals by ICP analysis. The correlation between soil properties and metals. The results indicated that pH and carbonates are the most important properties of these soils correlated with the metals (both micronutrients and heavy metals). The available micronutrients (all of them) are close correlated with the pH and carbonates in soils. Moreover, heavy metals like Pb and Ni are related to available Mn and Zn. Keywords: pH, carbonates, heavy metals, abandoned soils. References: Lindsay,W.L., andW.A. Norvell. 1978. "Development of a DTPA Soil Test for Zinc, Iron

Effects of combined amendments on crop yield and cadmium uptake in two cadmium contaminated soils under rice-wheat rotation.

PubMed

Guo, Fuyu; Ding, Changfeng; Zhou, Zhigao; Huang, Gaoxiang; Wang, Xingxiang

2018-02-01

Soil cadmium (Cd) contamination in China has become a serious concern due to its high toxicity to human health through food chains. A pot experiment was conducted to investigate the effects of hydrated lime (L), hydroxyapatite (H) and organic fertilizer (F) alone or in combination to remedy a mild (DY) and a moderate (YX) Cd contaminated agricultural soil under rice-wheat rotation. Results showed that crops grain yield and Cd concentration, soil pH, CaCl 2 extractable Cd and Cd speciation were markedly affected by the amendments. In both cropping seasons, hydrated lime and hydroxyapatite significantly immobilized soil Cd, and hydroxyapatite, organic fertilizer significantly increased grain yield. Hydrated lime mainly increased soil carbonates bound Cd fractions resulted from 16.7% to 36.2% and from 16.8% to 28.3%, and hydroxyapatite increased Fe/Mn oxides Cd fractions from 19.3% to 33.4% and from 31.4% to 42.1% in the DY and YX soils, respectively; while organic fertilizer slightly increased soil exchangeable and organic matter bound Cd fractions. Besides, combined amendments contain alkaline materials and organic materials have the potential to decrease grain Cd and increase grain yield simultaneously. Therefore, in view of the effects of amendments on grain yield and Cd concentration, the cost as well as the potential benefits expected, combined amendments like hydrated lime + organic fertilizer, hydrated lime + hydroxyapatite + organic fertilizer are recommended in practical application. Mechanisms of Cd immobilization affected by amendments are mainly attributed to the changes in soil Cd availability and crops root uptake rather than internal translocation in plants. Copyright © 2017 Elsevier Inc. All rights reserved.

Differences in soil solution chemistry between soils amended with nanosized CuO or Cu reference materials: implications for nanotoxicity tests.

PubMed

McShane, Heather V A; Sunahara, Geoffrey I; Whalen, Joann K; Hendershot, William H

2014-07-15

Soil toxicity tests for metal oxide nanoparticles often include micrometer-sized oxide and metal salt treatments to distinguish between toxicity from nanometer-sized particles, non-nanometer-sized particles, and dissolved ions. Test result will be confounded if each chemical form has different effects on soil solution chemistry. We report on changes in soil solution chemistry over 56 days-the duration of some standard soil toxicity tests-in three soils amended with 500 mg/kg Cu as nanometer-sized CuO (nano), micrometer-sized CuO (micrometer), or Cu(NO3)2 (salt). In the CuO-amended soils, the log Cu2+ activity was initially low (minimum -9.48) and increased with time (maximum -5.20), whereas in the salt-amended soils it was initially high (maximum -4.80) and decreased with time (minimum -6.10). The Cu2+ activity in the nano-amended soils was higher than in the micrometer-amended soils for at least the first 11 days, and lower than in the salt-amended soils for at least 28 d. The pH, and dissolved Ca and Mg concentrations in the CuO-amended soils were similar, but the salt-amended soils had lower pH for at least 14 d, and higher Ca and Mg concentrations throughout the test. Soil pretreatments such as leaching and aging prior to toxicity tests are suggested.

Effects and risk assessment of linear alkylbenzene sulfonates in agricultural soil. 5. Probabilistic risk assessment of linear alkylbenzene sulfonates in sludge-amended soils.

PubMed

Jensen, J; Løkke, H; Holmstrup, M; Krogh, P H; Elsgaard, L

2001-08-01

Linear alkylbenzene sulfonates (LAS) can be found in high concentrations in sewage sludge and, hence, may enter the soil compartment as a result of sludge application. Here, LAS may pose a risk for soil-dwelling organisms. In the present probabilistic risk assessment, statistical extrapolation has been used to assess the risk of LAS to soil ecosystems. By use of a log-normal distribution model, the predicted no-effect concentration (PNEC) was estimated for soil fauna, plants, and a combination of these. Due to the heterogeneous endpoints for microorganisms, including functional as well as structural parameters, the use of sensitivity distributions is not considered to be applicable to this group of organisms, and a direct, expert evaluation of toxicity data was used instead. The soil concentration after sludge application was predicted for a number of scenarios and used as the predicted environmental concentration (PEC) in the risk characterization and calculation of risk quotients (RQ = PEC/PNEC). A LAS concentration of 4.6 mg/kg was used as the current best estimate of PNEC in all RQ calculations. Three levels of LAS contamination (530, 2,600, and 16,100 mg/kg), three half-lives (10, 25, and 40 d), and five different sludge loads (2, 4, 6, 8, and 10 t/ha) were included in the risk scenarios. In Denmark, the initial risk ratio would reach 1.5 in a realistic worst-case consideration. For countries not having similar sludge regulations, the estimated risk ratio may initially be considerably higher. However, even in the most extreme scenarios, the level of LAS is expected to be well beyond the estimated PNEC one year after application. The present risk assessment, therefore, concludes that LAS does not pose a significant risk to fauna, plants, and essential functions of agricultural soils as a result of normal sewage sludge amendment. However, risks have been identified in worst-case scenarios.

Distinct responses in ammonia-oxidizing archaea and bacteria after addition of biosolids to an agricultural soil.

PubMed

Kelly, John J; Policht, Katherine; Grancharova, Tanya; Hundal, Lakhwinder S

2011-09-01

The recently discovered ammonia-oxidizing archaea (AOA) have been suggested as contributors to the first step of nitrification in terrestrial ecosystems, a role that was previously assigned exclusively to ammonia-oxidizing bacteria (AOB). The current study assessed the effects of agricultural management, specifically amendment of soil with biosolids or synthetic fertilizer, on nitrification rates and copy numbers of archaeal and bacterial ammonia monooxygenase (amoA) genes. Anaerobically digested biosolids or synthetic fertilizer was applied annually for three consecutive years to field plots used for corn production. Biosolids were applied at two loading rates, a typical agronomic rate (27 Mg hectare(-1) year(-1)) and double the agronomic rate (54 Mg hectare(-1) year(-1)), while synthetic fertilizer was applied at an agronomic rate typical for the region (291 kg N hectare(-1) year(-1)). Both biosolids amendments and synthetic fertilizer increased soil N and corn yield, but only the biosolids amendments resulted in significant increases in nitrification rates and increases in the copy numbers of archaeal and bacterial amoA genes. In addition, only archaeal amoA gene copy numbers increased in response to biosolids applied at the typical agronomic rate and showed a significant correlation with nitrification rates. Finally, copy numbers of archaeal amoA genes were significantly higher than copy numbers of bacterial amoA genes for all treatments. These results implicate AOA as being primarily responsible for the increased nitrification observed in an agricultural soil amended with biosolids. These results also support the hypothesis that physiological differences between AOA and AOB may enable them to occupy distinct ecological niches.

Watershed soil Cd loss after long-term agricultural practice and biochar amendment under four rainfall levels.

PubMed

Ouyang, Wei; Huang, Weijia; Hao, Xin; Tysklind, Mats; Haglund, Peter; Hao, Fanghua

2017-10-01

Some heavy metals in farmland soil can be transported into the waterbody, affecting the water quality and sediment at the watershed outlet, which can be used to determine the historical loss pattern. Cd is a typical heavy metal leached from farmland that is related to phosphate fertilizers and carries serious environmental risk. The spatial-vertical pattern of Cd in soil and the vertical trend of Cd in the river sediment core were analyzed, which showed the migration and accumulation of Cd in the watershed. To prevent watershed Cd loss, biochar was employed, and leaching experiments were conducted to investigate the Cd loss from soil depending on the initial concentration. Four rainfall intensities, 1.25 mm/h, 2.50 mm/h, 5.00 mm/h, and 10.00 mm/h, were used to simulate typical rainfall scenarios for the study area. Biochar was prepared from corn straw after pretreatment with ammonium dihydrogen phosphate (ADP) and pyrolysis at 400 °C under anoxic conditions. To identify the effects of biochar amendment on Cd migration, the biochar was mixed with soil for 90 days at concentrations of 0%, 0.5%, 1.0%, 3.0%, and 5.0% soil by weight. The results showed that the Cd leaching load increased as the initial load and rainfall intensity increased and that eluviation caused surface Cd to diffuse to the deep soils. The biochar application caused more of the heavy metals to be immobilized in the amended soil rather than transported into the waterbody. The sorption efficiency of the biochar for Cd increased as the addition level increased to 3%, which showed better performance than the 5% addition level under some initial concentration and rainfall conditions. The research indicated that biochar is a potential material to prevent diffuse heavy metal pollution and that a lower addition makes the application more feasible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leaching of nitrogen and base cations from calcareous soil amended with organic residues.

PubMed

Zarabi, Mahboubeh; Jalali, Mohsen

2012-01-01

The potential for groundwater and surface water pollution by nutrients in organic residues, primarily nitrogen (N) and base cations (K+, Na+, Ca2+, Mg2+), is a consideration when applying such residues to land. In this study, we used a laboratory column leaching procedure to examine the leaching of N, K+, Na+, Ca2+ and Mg2+ in soils treated with two types of raw organic residues (poultry manure and potato residues) and one municipal waste compost, which are currently recycled on agricultural land in Iran. Each organic residue was thoroughly mixed with two different soils (sandy loam and clay) at the rate of 3%. Soil columns were leached at 4-d intervals for 92 d with distilled water, and effluents were analysed for pH, EC, nitrate (NO3(-)-N), ammonium (NH4(+)-N) K+, Na+, Ca2+ and Mg2+. The results indicated that the amounts of NO3(-)-N and NH4(+)-N leached from the poultry manure and potato residues could represent very important economic losses of N and pose an environmental threat under field conditions. The sandy loam soil amended with poultry manure lost the highest amount of NO3(-)-N (206.4 kg ha(-1)), and clay soil amended with poultry manure lost the highest amounts of NH4(+)-N (454.3 kg ha(-1)). The results showed that a treatment incorporating 3% of municipal waste compost could be used without negative effects to groundwater N concentration in clay soil. Significant amounts of K+, Na+, Ca2+, and Mg2+ were leached owing to the application of poultry manure, potato and municipal waste compost to soils. There was a positive relationship between K+, Na+, Ca2+, and Mg2+ with NO3(-)-N and NH4(+)-N leached in soils. Analysis of variance detected significant effects of amendment, soil type and time on the leaching NO3(-)-N, NH4(+)-N, K+, Na+, Ca2+ and Mg2+.

Designing relevant biochars as soil amendments using lignocellulosic-based and manure-based feedstocks

EPA Science Inventory

Purpose: Biochars are a soil amendment produced from lignocellulosic and manure feedstocks. Not all biochars are viable soil amendments because of differences in their physical and chemical properties. Biochar could deliver more effective service as a soil amendment if its chemis...

Nitric oxide emissions from soils amended with municipal waste biosolids

NASA Astrophysics Data System (ADS)

Roelle, Paul A.; Aneja, Viney P.

Land spreading nitrogen-rich municipal waste biosolids (NO 3--N<256 mg N kg -1 dry weight, NH 3-N˜23,080 mg N kg -1 dry weight, Total Kjeldahl N˜41,700 mg N kg -1 dry weight) to human food and non-food chain land is a practice followed throughout the US. This practice may lead to the recovery and utilization of the nitrogen by vegetation, but it may also lead to emissions of biogenic nitric oxide (NO), which may enhance ozone pollution in the lower levels of the troposphere. Recent global estimates of biogenic NO emissions from soils are cited in the literature, which are based on field measurements of NO emissions from various agricultural and non-agricultural fields. However, biogenic emissions of NO from soils amended with biosolids are lacking. Utilizing a state-of-the-art mobile laboratory and a dynamic flow-through chamber system, in-situ concentrations of nitric oxide (NO) were measured during the spring/summer of 1999 and winter/spring of 2000 from an agricultural soil which is routinely amended with municipal waste biosolids. The average NO flux for the late spring/summer time period (10 June 1999-5 August 1999) was 69.4±34.9 ng N m -2 s -1. Biosolids were applied during September 1999 and the field site was sampled again during winter/spring 2000 (28 February 2000-9 March 2000), during which the average flux was 3.6±1.7 ng N m -2 s -1. The same field site was sampled again in late spring (2-9 June 2000) and the average flux was 64.8±41.0 ng N m -2 s -1. An observationally based model, developed as part of this study, found that summer accounted for 60% of the yearly emission while fall, winter and spring accounted for 20%, 4% and 16% respectively. Field experiments were conducted which indicated that the application of biosolids increases the emissions of NO and that techniques to estimate biogenic NO emissions would, on a yearly average, underestimate the NO flux from this field by a factor of 26. Soil temperature and % water filled pore space

Mitigation of dimethazone residues in soil and runoff water from agricultural field.

PubMed

Antonious, George F

2011-01-01

Dimethazone, also known as clomazone [2-[(2-chlorophenyl) methyl]- 4,4-dimethyl-3-isoxaolidinone] is a pre-emergent nonionic herbicide commonly used in agriculture. A field study was conducted on a silty-loam soil of 10 % slope to monitor off-site movement and persistence of dimethazone in soil under three management practices. Eighteen plots of 22 x 3.7 m each were separated using stainless steel metal borders and the soil in six plots was mixed with municipal sewage sludge (MSS) and yard waste (YW) compost (MSS+YW) at 15 t acre⁻¹ on dry weight basis, six plots were mixed with MSS at 15 t acre⁻¹, and six unamended plots (NM) were used for comparison purposes. The objectives of this investigation were to: (i) monitor the dissipation and half-life (T₁/₂) of dimethazone in soil under three management practices; (ii) determine the concentration of dimethazone residues in runoff and infiltration water following natural rainfall events; and (iii) assess the impact of soil amendments on the transport of NO₃, NH₄, and P into surface and subsurface water. Gas chromatography/mass spectrometery (GC/MS) analyses of soil extracts indicated the presence of ion fragments at m/z 125 and 204 that can be used for identification of dimethazone residues. Intitial deposits of dimethazone varied from 1.3 μg g⁻¹ dry native soil to 3.2 and 11.8 μg g⁻¹ dry soil in MSS and MSS+YW amended soil, respectively. Decline of dimethazone residues in the top 15 cm native soil and soil incorporated with amendments revealed half-life (T₁/₂) values of 18.8, 25.1, and 43.0 days in MSS+YW, MSS, and NM treatments, respectively. Addition of MSS+YW mix and MSS alone to native soil increased water infiltration, lowering surface runoff water volume and dimethazone residues in runoff following natural rainfall events.

Lead Speciation and In Vitro Bioaccessibility of Compost-Amended Urban Garden Soils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Attanayake, Chammi P.; Hettiarachchi, Ganga M.; Ma, Qing

In situ soil amendments can modify the Pb bioavailability by changing soil Pb speciation. Urban soils from three vegetable gardens containing different total Pb concentrations were used. The study evaluated how compost amendment and aging of soil-compost mixture in situ affected the following: (i) soil Pb speciation in the field and (ii) change of soil Pb speciation during an in vitro bioaccessibility extraction mimicking gastric phase dissolution at pH 2.5. X-ray absorption fine structure spectroscopy was used to determine Pb speciation in amended and nonamended soils and residues left after in vitro bioaccessibility extraction of those soils. Compost amendment andmore » aging of compost in the field had a negligible effect on Pb bioaccessibility in the soils. Major Pb species in the soils were Pb sorbed to Fe oxy(hydr)oxide (Pb-Fh) and to soil organic C (Pb-Org). The fraction of Pb-Org was increased as soil-compost mixture aged in the field. During the in vitro extraction, the fraction of Pb-Fh was decreased, the fraction of Pb-Org was increased, and hydroxypyromorphite was formed in both amended and nonamended soils. Freshly incorporated compost enhanced the dissolution of Pb-Fh during the extraction. As soil-compost mixture aged in the field, the dissolution of Pb-Fh was low, demonstrating more stability of the Pb-Fh during the extraction. Compost amendment showed potential to contribute to reduced bioaccessibility of Pb as compost aged in the soil by increasing Pb-Org fraction in the field and stability of Pb-Fh during the in vitro bioaccessibility extraction.« less

Evaluation of emission of greenhouse gases from soils amended with sewage sludge.

PubMed

Paramasivam, S; Fortenberry, Gamola Z; Julius, Afolabi; Sajwan, Kenneth S; Alva, A K

2008-02-01

Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate

Application of MCPA herbicide on soils amended with biostimulants: short-time effects on soil biological properties.

PubMed

Tejada, Manuel; García-Martínez, Ana M; Gómez, Isidoro; Parrado, Juan

2010-08-01

In this paper we studied in the laboratory the effect of MCPA herbicide at a rate of 1.5lha(-1) (manufactures rate recommended) on biological properties of a Plagic Antrosol amended with four biostimulants (WCDS, wheat condensed distillers soluble; PA-HE, hydrolyzed poultry feathers; CGHE, carob germ enzymatic extract; and RB, rice bran extract). Seven hundred grams of soil were mixed with WCDS at a rate of 10%, CGHE at a rate of 4.7%, PA-HE at a rate of 4.3%, and RB at a rate of 4.4%, respectively, in order to applying the same amount of organic matter to the soil (16.38 g organic matter). An unamended polluted and amended non-polluted soil were used as control. For all treatments, the soil ergosterol, dehydrogenase, urease, and phosphatase activities were measured at two incubation times (0 and 60 d). The 16S rDNA-DGGE profiles in all treatments were determined at the beginning and end of the incubation period. The results indicated that at the end of the incubation period and compared with the control soil, the dehydrogenase, urease and phosphatase activities and ergosterol decreased 39.3%, 20%, 15.7% and 56.5%, respectively in the non-organic amended polluted soil. The application of organic matter to unpolluted soil increased the enzymatic activities and ergosterol. However, this stimulation was higher in the soil amended with RB, followed by PA-HE, WCDS and CGHE. The application of herbicide in organic-amended soils decreased the enzymatic activities and ergosterol content. However, this decrease was lower than for the non-amended herbicide polluted soil. Possibly the low molecular weight protein content easily assimilated by soil microorganisms and the adsorption capacity of humic substances are responsible for less inhibition of these enzyme activities and soil ergosterol. The 16S rDNA-DGGE profiles indicated that herbicide did not negatively affect soil bacterial biodiversity. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Knowledge needs, available practices, and future challenges in agricultural soils

NASA Astrophysics Data System (ADS)

Key, Georgina; Whitfield, Mike G.; Cooper, Julia; De Vries, Franciska T.; Collison, Martin; Dedousis, Thanasis; Heathcote, Richard; Roth, Brendan; Mohammed, Shamal; Molyneux, Andrew; Van der Putten, Wim H.; Dicks, Lynn V.; Sutherland, William J.; Bardgett, Richard D.

2016-10-01

The goal of this study is to clarify research needs and identify effective practices for enhancing soil health. This was done by a synopsis of soil literature that specifically tests practices designed to maintain or enhance elements of soil health. Using an expert panel of soil scientists and practitioners, we then assessed the evidence in the soil synopsis to highlight practices beneficial to soil health, practices considered detrimental, and practices that need further investigation. A partial Spearman's correlation was used to analyse the panel's responses. We found that increased certainty in scientific evidence led to practices being considered to be more effective due to them being empirically justified. This suggests that for practices to be considered effective and put into practice, a substantial body of research is needed to support the effectiveness of the practice. This is further supported by the high proportion of practices (33 %), such as changing the timing of ploughing or amending the soil with crops grown as green manures, that experts felt had unknown effectiveness, usually due to insufficiently robust evidence. Only 7 of the 27 reviewed practices were considered to be beneficial, or likely to be beneficial in enhancing soil health. These included the use of (1) integrated nutrient management (organic and inorganic amendments); (2) cover crops; (3) crop rotations; (4) intercropping between crop rows or underneath the main crop; (5) formulated chemical compounds (such as nitrification inhibitors); (6) control of traffic and traffic timing; and (7) reducing grazing intensity. Our assessment, which uses the Delphi technique, is increasingly used to improve decision-making in conservation and agricultural policy, identified practices that can be put into practice to benefit soil health. Moreover, it has enabled us to identify practices that need further research and a need for increased communication between researchers, policy-makers, and

Global Warming Potential from early phase decomposition of soil organic matter amendments

NASA Astrophysics Data System (ADS)

Mayer, A.; Silver, W. L.

2015-12-01

Organic matter amendments to soil are widely used as a method of enhancing nutrient availability for crops or grassland. Amendments such as composted manure or greenwaste also have the co-benefits of potentially increasing soil carbon (C) stocks (DeLonge et al., 2013) and diverting organic waste from landfills or manure lagoons. However, application of organic matter amendments can also stimulate emissions of greenhouse gases (GHGs). In this study we determined how the chemical quality of organic matter amendments affected soil C and N content and GHG emissions during early stage decomposition. California grassland soils were amended with six different amendments of varying C and N content including three composts and three feedstocks (goat and horse bedding and cattle manure). Amendments and soils were incubated in the laboratory for 7 weeks; GHG fluxes were measured weekly. The three feedstocks emitted significantly more GHGs than the composted materials. With the exception of cow manure, N content of the amendment was linearly correlated with global warming potential emitted (R2= 0.66, P <0.0001). C:N ratios were not a significant predictor of GHG emissions. Cow manure stimulated a net loss of C (or C equivalents) in the mineral soil, as expected. However, greenwaste compost also surprisingly resulted in net C losses, while goat bedding, horse bedding, and the other compost were either C neutral or a slight net C sink at the end of the incubation. Ongoing analyses are examining the fate of the C incorporated from the amendment to the soil as occluded or free light fraction, as well as N mineralization rates. Our data suggest that N content of organic matter amendments is a good predictor of initial GHG emissions. The study also indicates that composting greenwaste with N-rich bedding and manure can result in lower GHG emissions and C sequestration compared to the individual uncomposted components.

Response of wine grape growth, development and the transfer of copper, lead, and cadmium in soil-fruit system to sludge compost amendment.

PubMed

Liu, Hong-Tao; Wang, Yan-Wen; Huang, Wei-Dong; Lei, Mei

2016-12-01

Sludge is an organic waste after domestic sewage being treated and contains phytonutrients and organic matter. In this study, recycling of sludge compost (SC) and its compound fertilizer (SCF) to wine grape resulted in improvement in vegetative growth, reproductive development of wine grape, and potential wine quality of grape fruit. The amounts of Cu, Pb, and Cd in grape fruit were significantly higher in response to sludge amendment than in the control, but were all below the permissible limits for agricultural product. The contents of Cu and Pb in sludge-amended soil decreased with increasing soil depth, but Cd content increased with soil depth. Ongoing monitoring of on mobility of Cd downward is proposed with sludge recycling to wine grape soil.

Biodegradation of Used Motor Oil in Soil Using Organic Waste Amendments

PubMed Central

Abioye, O. P.; Agamuthu, P.; Abdul Aziz, A. R.

2012-01-01

Soil and surface water contamination by used lubricating oil is a common occurrence in most developing countries. This has been shown to have harmful effects on the environment and human beings at large. Bioremediation can be an alternative green technology for remediation of such hydrocarbon-contaminated soil. Bioremediation of soil contaminated with 5% and 15% (w/w) used lubricating oil and amended with 10% brewery spent grain (BSG), banana skin (BS), and spent mushroom compost (SMC) was studied for a period of 84 days, under laboratory condition. At the end of 84 days, the highest percentage of oil biodegradation (92%) was recorded in soil contaminated with 5% used lubricating oil and amended with BSG, while only 55% of oil biodegradation was recorded in soil contaminated with 15% used lubricating oil and amended with BSG. Results of first-order kinetic model to determine the rate of biodegradation of used lubricating oil revealed that soil amended with BSG recorded the highest rate of oil biodegradation (0.4361 day−1) in 5% oil pollution, while BS amended soil recorded the highest rate of oil biodegradation (0.0556 day−1) in 15% oil pollution. The results of this study demonstrated the potential of BSG as a good substrate for enhanced remediation of hydrocarbon contaminated soil at low pollution concentration. PMID:22919502

Metal availability, soil nutrient, and enzyme activity in response to application of organic amendments in Cd-contaminated soil.

PubMed

Yang, Zhanbiao; Liu, Lixia; Lv, Yanfeng; Cheng, Zhang; Xu, Xiaoxun; Xian, Junren; Zhu, Xuemei; Yang, Yuanxiang

2018-01-01

The study investigated the effects of organic amendments: green tea amendment (GTA) and oil cake amendment (OCA) on Cd bioavailability, soil nutrients, and soil enzyme activity in Cd-contaminated soil. The amendments were added to the soil at the doses of 1, 3, and 5% and were incubated for 45 days. Then, pakchoi cabbage was planted to test the remediation effect of the above two organic amendments. The diethylenetriaminepentaacetic acid (DTPA)-extractable Cd in GTA and OCA treatments was reduced by 14.69-27.51 and 13.75-68.77%, respectively, compared to no amendment-applied treatment. The application of GTA and OCA notably decreased the proportion of exchangeable fraction of Cd, but increased the percentage of oxide and organic-bound fraction of Cd, thereby suppressing the uptake by pakchoi cabbage. Cd concentration of aboveground parts decreased by 8.21-18.05 and 7.77-35.89% in GTA and OCA treatments, respectively. Relative to the no amendment-applied treatment, both GTA and OCA had enhanced soil nutrients and enzyme activities largely. Redundancy analysis showed that organic matter, total P, available N, and DTPA-extractable Cd significantly affected the enzyme activities. Furthermore, the application of OCA at the dose of 5% was more effective in reducing bioavailable Cd, enhancing soil available nutrients and urease and catalase activities in contaminated soil. These results indicated that oil cake should be used to immobilize metal and improve fertility and quality of Cd-contaminated soil.

Multivariate regulation of soil CO2 and N2 O pulse emissions from agricultural soils.

PubMed

Liang, Liyin L; Grantz, David A; Jenerette, G Darrel

2016-03-01

Climate and land-use models project increasing occurrence of high temperature and water deficit in both agricultural production systems and terrestrial ecosystems. Episodic soil wetting and subsequent drying may increase the occurrence and magnitude of pulsed biogeochemical activity, affecting carbon (C) and nitrogen (N) cycles and influencing greenhouse gas (GHG) emissions. In this study, we provide the first data to explore the responses of carbon dioxide (CO2 ) and nitrous oxide (N2 O) fluxes to (i) temperature, (ii) soil water content as percent water holding capacity (%WHC), (iii) substrate availability throughout, and (iv) multiple soil drying and rewetting (DW) events. Each of these factors and their interactions exerted effects on GHG emissions over a range of four (CO2 ) and six (N2 O) orders of magnitude. Maximal CO2 and N2 O fluxes were observed in environments combining intermediate %WHC, elevated temperature, and sufficient substrate availability. Amendments of C and N and their interactions significantly affected CO2 and N2 O fluxes and altered their temperature sensitivities (Q10 ) over successive DW cycles. C amendments significantly enhanced CO2 flux, reduced N2 O flux, and decreased the Q10 of both. N amendments had no effect on CO2 flux and increased N2 O flux, while significantly depressing the Q10 for CO2 , and having no effect on the Q10 for N2 O. The dynamics across DW cycles could be attributed to changes in soil microbial communities as the different responses to wetting events in specific group of microorganisms, to the altered substrate availabilities, or to both. The complex interactions among parameters influencing trace gas fluxes should be incorporated into next generation earth system models to improve estimation of GHG emissions. © 2015 John Wiley & Sons Ltd.

In situ stabilization of cadmium-, lead-, and zinc-contaminated soil using various amendments.

PubMed

Lee, Sang-Hwan; Lee, Jin-Soo; Choi, Youn Jeong; Kim, Jeong-Gyu

2009-11-01

Chemical stabilization is an in situ remediation method that uses inexpensive amendments to reduce contaminant availability in polluted soil. We tested the effects of several amendments (limestone, red-mud, and furnace slag) on the extractability of heavy metals, microbial activities, phytoavailability of soil metals (assessed using lettuce, Lactuca sativa L.), and availability of heavy metals in ingested soil to the human gastrointestinal system (assessed using the physiologically based extraction test). The application of soil amendments significantly decreased the amount of soluble and extractable heavy metals in the soil (p<0.05). The decreased extractable metal content of soil was accompanied by increased microbial activity and decreased plant uptake of heavy metals. Soil microbial activities (soil respiration, urease, and dehydrogenase activity) significantly increased in limestone and red-mud-amended soils. Red-mud was the most effective treatment in decreasing heavy-metal concentrations in lettuce. Compared to non-amended control soil, lettuce uptake of Cd, Pb, and Zn was reduced 86%, 58%, and 73%, respectively, by the addition of red-mud.

Nitrogen and carbon pools in an agricultural soil amended with natural and NH4-enriched K-Chabazite zeolitite

NASA Astrophysics Data System (ADS)

Ferretti, Giacomo; Faccini, Barbara; Vittori Antisari, Livia; Di Giuseppe, Dario; Massimo, Coltorti

2015-04-01

Nitrogen and Carbon pools in a reclaimed agricultural soil amended with 5 to 15 Kg m-2 of natural and NH4-enriched (K-Chabazite) zeolitites have been investigated. Zeolitites were enriched by means of static exchange with a swine slurry in a prototype (ZeoLIFE Project, www.zeolife.it). The experimental field is located in the Po Delta plain near Codigoro (Ferrara, Italy), it extends over an area of about 6 ha and it was divided in six parcels. The field has been heavily fertilized with chemical fertilizers and livestock sewage since 1960. Nowadays the area is part of the Nitrate Vulnerable Zones (Nitrate Directive 91/676/CEE) and a maximum annual input of 170 Kg-N ha-1 must be respected. With respect to the control parcels, at the end of the agronomic year, sorghum yield was 4% and 14% higher in the parcels treated with natural zeolitite and in that treated with NH4-enriched zeolitite, respectively. This notwithstanding the N fertilizers reduction from 30% in the former to 50% in the latter. Beside the yield improvement, N and C pools are affected by the use of zeolitite and relevant changes have been noticed. i) δ15N ratios in both soil (total and fixed N-NH4 inside the clay interlayer and zeolite exchange sites) and different organs of the sorghum crops show that the N-NH4 stocked in the enriched zeolitite has been transferred to the crops and preferentially stocked in the leaves with respect to the N-NH4 provided by chemical fertilizer. ii) The active role of fixed N-NH4 pool in mineral nutrition of the crops and its replacement can be due to inorganic N fertilizers (Urea and Diammonium Phosphate). This pool in fact decreased during the crops growth, suggesting that it represented an important contribution to the active N pool in the soil. iii) Due to the high N content in this agricultural field, no significant total N decrease was observed during the growing season, which is also responsible for the low C/N ratio in the soil. After the N input from NH4

Chemically assisted phytoextraction: a review of potential soil amendments for increasing plant uptake of heavy metals.

PubMed

Meers, E; Tack, F M G; Van Slycken, S; Ruttens, A; Du Laing, G; Vangronsveld, J; Verloo, M G

2008-01-01

The contamination of soils by trace metals has been an unfortunate sideeffect of industrialization. Some of these contaminants can interfere with vulnerable enduses of soil, such as agriculture or nature, already at relatively low levels of contamination. Reversely, conventional civil-technical soil-remediation techniques are too expensive to remediate extended areas of moderately contaminated soil. Phytoextraction has been proposed as a more economic complementary approach to deal with this specific niche of soil contamination. However, phytoextraction has been shown to be a slow-working process due to the low amounts of metals that can be annually removed from the soil under normal agronomic conditions. Therefore, extensive research has been conducted on process optimization by means of chemically improving plant availability and the uptake of heavy metals. A wide range of potential amendments has been proposed in the literature, with considerable attention being spent on aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA). However, these compounds have received increasing criticism due to their environmental persistence and associated risks for leaching. This review presents an overview of potential soil amendments that can be employed for enhancing metal uptake by phytoextraction crops, with a distinct focus on more degradable alternatives to persistent compounds such as EDTA.

Impact of biochar amendment on soil water soluble carbon in the context of extreme hydrological events.

PubMed

Wang, Daoyuan; Griffin, Deirdre E; Parikh, Sanjai J; Scow, Kate M

2016-10-01

Biochar amendments to soil have been promoted as a low cost carbon (C) sequestration strategy as well as a way to increase nutrient retention and remediate contaminants. If biochar is to become part of a long-term management strategy, it is important to consider its positive and negative impacts, and their trade-offs, on soil organic matter (SOM) and soluble C under different hydrological conditions such as prolonged drought or frequent wet-dry cycles. A 52-week incubation experiment measuring the influence of biochar on soil water soluble C under different soil moisture conditions (wet, dry, or wet-dry cycles) indicated that, in general, dry and wet-dry cycles increased water soluble C, and biochar addition further increased release of water soluble C from native SOM. Biochar amendment appeared to increase transformation of native SOM to water soluble C, based on specific ultraviolet absorption (SUVA) and C stable isotope composition; however, the increased amount of water soluble C from native SOM is less than 1% of total biochar C. The impacts of biochar on water soluble C need to be carefully considered when applying biochar to agricultural soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Amendment soil with biochar to control antibiotic resistance genes under unconventional water resources irrigation: Proceed with caution.

PubMed

Cui, Er-Ping; Gao, Feng; Liu, Yuan; Fan, Xiang-Yang; Li, Zhong-Yang; Du, Zhen-Jie; Hu, Chao; Neal, Andrew L

2018-05-10

The spread of antibiotic resistance genes (ARGs) has become a cause for serious concern because of its potential risk to public health. The use of unconventional water resources (e.g., reclaimed water or piggery wastewater) in agriculture to relieve groundwater shortages may result in an accumulation of ARGs in soil. Biochar addition has been proven to be a beneficial method to alleviate the pollution of ARGs in manure-amended soil. However, the role of biochar on ARGs in soil-plant systems repeatedly irrigated with unconventional water resources is unknown. Under reclaimed water or piggery wastewater irrigation, rhizobox experiments using maize plants in soil amended with biochar were conducted to investigate the variation of typical ARGs (tet and sul genes) in soil-plant systems during a 60-day cultivation, and ARGs was characterized by high-throughput qPCR with a 48 (assays) × 108 (samples) array. Only piggery wastewater irrigation significantly increased the abundance of ARGs in rhizosphere and bulk soils and root endophytes. Following 30-day cultivation, the abundance of ARGs in soil was significantly lower due to biochar addition. However, by day 60, the abundance of ARGs in soil supplemented with biochar was significantly higher than in the control soils. Antibiotics, bio-available heavy metals, nutrients, bacterial community, and mobile gene elements (MGEs) were detected and analyzed to find factors shaping ARGs dynamics. The behavior of ARGs were associated with antibiotics but not with bio-available heavy metals. The correlation between ARGs and available phosphorus was stronger than that of ARGs with total phosphorus. MGEs had good relationship with ARGs, and MGEs shifts contributed most to ARGs variation in soil and root samples. In summary, this study provides insights into potential options for biochar use in agricultural activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of different rates of spent mushroom substrate on the dissipation and bioavailability of cymoxanil and tebuconazole in an agricultural soil.

PubMed

Álvarez-Martín, Alba; Sánchez-Martín, María Jesús; Pose-Juan, Eva; Rodríguez-Cruz, María Sonia

2016-04-15

Physicochemical methods to immobilize pesticides in vulnerable soils are currently being developed to prevent water contamination. Some of these methods include the use of different organic residues to modify soils because they could limit the transport of pesticides and/or facilitate their dissipation. Spent mushroom substrate (SMS) may be used for these purposes. Accordingly a study was conducted under laboratory conditions to know the dissipation and bioavailability of the fungicides cymoxanil and tebuconazole over time in a vineyard soil amended with two rates of spent mushroom substrate (SMS) (5% and 50% (w/w)), selected to prevent the diffuse or point pollution of soil. The dissipation of cymoxanil was more rapid than that of tebuconazole in the different soils studied. The dissipation rate was higher in the amended soil than in the unamended one for both compounds, while no significant differences were observed between the amended soils in either case. An apparent dissipation occurred in the amended soil due to the formation of non-extractable residues. Bound residues increased with incubation time for tebuconazole, although a proportion of this fungicide was bioavailable after 303days. The major proportion of cymoxanil was tightly bound to the amended soil from the start, although an increasing fraction of bound fungicide was bioavailable for mineralization. Soil dehydrogenase activity was significantly affected by SMS application and incubation time; however, it was not significantly modified by fungicide application. The significance of this research suggests that SMS applied at a low or high rate to agricultural soil can be used to prevent both the diffuse or point pollution of soil through the formation of non-extractable residues, although more research is needed to discover the time that fungicides remain adsorbed into the soil decreasing either bioavailability (tebuconazole) or mineralization (cymoxanil) in SMS-amended soils. Copyright © 2016

Effects of N-ammonoxidized lignins amendment on N availability and soil fertility: An incubation study

NASA Astrophysics Data System (ADS)

María De la Rosa, José; López-Martín, María; Liebner, Falk; Knicker, Heike

2013-04-01

The shift towards a biobased economy will probably generate the application of bioenergy by-products and charred residues to the soil as either amendments or fertilizers. The process of ammonoxidation (application of gaseous oxygen and aqueous ammonia under ambient pressure breaks down aromatic lignin moieties and introduces N in the form of urea, amides and amines), converts lignin, a major by-product of the pulp and paper industry, or other ligneous materials into artificial humic matter (N-lignin). The use of N-ammonoxidized lignin as soil improvers is in theory an economically viable solution, especially interesting for agricultural areas of Mediterranean countries, in which additional factors such as water shortage and fires contribute to declining N availability by lowering nutrient diffusion, litter input or sequestration of N in charred structures. However, limited research has been done to determine how this will influence C and N dynamics and soil fertility. Therefore we performed pot experiments in which a perennial ryegrass (Lolium perenne L.) was grown on a typical Andalusian soil (chromic Luvisol) after amendment of N-lignins highly enriched in 15N (Sarkanda and Indulin ammonoxidized lignins) for 75 days. For comparison, the incubation was also carried out on soils fertilized with 15NO3 and unfertilized (control). The application of ammonoxidized lignins altered the pH and electrical conductivity of the soil. At higher concentrations a retardation of seed germination was evidenced, an observation that needs further considerations before N-enriched technical lignins can be applied in agriculture. After 75 days, the plant shoots from the pots amended with15N-Indulin and 15N-Sarkanda accumulated 8% and 20%, respectively of the initial 15N (15N0). The N was efficiently sequestered from fast release or leaching and most of 15N0 remained in the soil (64%) in the 15N-Indulin pots. In contrast, the 15N-Sarkanda pots showed a lower efficiency in the N

Effects of aluminium water treatment residuals, used as a soil amendment to control phosphorus mobility in agricultural soils.

PubMed

Ulén, Barbro; Etana, Ararso; Lindström, Bodil

2012-01-01

Phosphorus (P) leaching from agricultural soils is a serious environmental concern. Application of aluminium water treatment residuals (Al-WTRs) at a rate of 20 Mg ha(-1) to clay soils from central Sweden significantly increased mean topsoil P sorption index (PSI) from 4.6 to 5.5 μmol kg(-1) soil. Mean degree of P saturation in ammonium lactate extract (DPS-AL) significantly decreased from 17 to 13%, as did plant-available P (P-AL). Concentrations of dissolved reactive P (DRP) decreased by 10-85% in leaching water with Al-WTR treatments after exposure of topsoil lysimeters to simulated rain. Soil aggregate stability (AgS) for 15 test soils rarely improved. Three soils (clay loam, silty loam and loam sand) were tested in greenhouse pot experiments. Aluminium-WTR application of 15 or 30 ton ha(-1) to loam sand and a clay loam with P-AL values of 80-100 mg kg(-1) soil significantly increased growth of Italian ryegrass when fertilised with P but did not significantly affect growth of spring barley on any soil. Al-WTR should only be applied to soils with high P fertility where improved crop production is not required.

The roles of nematodes in nitrogen and phosphorous availability, plant uptake and growth in organically amended soils

NASA Astrophysics Data System (ADS)

Gebremikael, Mesfin; Buchan, David; De Neve, Stefaan

2017-04-01

Several studies have shown that soil biota contributes significantly to the crucial ecosystem functions and services such as organic matter decomposition and nutrient cycling. The contribution of each group of soil organisms may vary depending primarily on their feeding behavior. The magnitude of the ecosystem services by the biota may also depend on the interactions amongst the soil biota groups and their surrounding environment, for instance, biochemical characteristics of the externally added organic material. However, only a few studies considered these interactions concurrently. Here, we investigated the effects of fauna-microbe-plant interactions on organic matter decomposition and nutrient cycling by applying different organic materials spanning a range of C:N ratios and presumed N availability. Nematodes were selected as model fauna because they are the most abundant soil metazoans that have a diversified feeding strategy and interact very intimately with microbes, other fauna, and plants. A series of incubation experiments were conducted in bare and planted microcosms under controlled conditions using fresh soil collected from an agricultural field and defaunated by gamma irradiation. In the first experiment without plants, the defaunated soil cores were either left unamended (UNA) or received lignin-rich low N compost (COI), N-rich compost (COV), fresh manure (MAN) or chopped clover (CLO). The entire free-living soil nematode community was extracted from unirradiated fresh soil and reinoculated into half of the soil cores that had been defaunated by gamma irradiation. Two treatments: with (+Nem) and without (-Nem) nematodes were compared for soil nitrogen and phosphorus availability, plant uptake, and PLFA signatures over time during a 105-days incubation. The same experimental setup was used to investigate further the CLO amendment in the presence of plants (rye grass was used as a model plant). Nematodes were extracted and assigned to feeding groups

Evolution of organic matter fractions after application of co-compost of sewage sludge with pruning waste to four Mediterranean agricultural soils. A soil microcosm experiment.

PubMed

Pérez-Lomas, A L; Delgado, G; Párraga, J; Delgado, R; Almendros, G; Aranda, V

2010-10-01

The effect of co-compost application from sewage sludge and pruning waste, on quality and quantity of soil organic carbon (SOC) in four Mediterranean agricultural soils (South Spain), was studied in soil microcosm conditions. Control soil samples (no co-compost addition) and soils treated with co-composts to a rate equivalent of 140 Mg ha(-1) were incubated for 90 days at two temperatures: 5 and 35 degrees C. The significances of incubation temperature and the addition of co-compost, on the evolution of the different fractions of SOC, were studied using a 2(3) factorial design. The co-compost amendment increased the amounts of humic fractions: humic acids (HA) (1.9 times), fulvic acids (FA) (3.3 times), humin (1.5 times), as well as the free organic matter (1.4 times) and free lipids (21.8 times). Incubation of the soils enhanced its biological activity mainly in the amended soils and at 35 degrees C, leading to progressive SOC mineralization and humification, concomitant to the preferential accumulation of HA. The incubation results show large differences depending on temperature and soil types. This fact allows us to select suitable organic amendment for the soil when a rapid increase in nutrients through mineralization is preferred, or in cases intending the stabilization and preservation of the SOC through a process of humification. In soils with HA of more than 5 E(4)/E(6) ratio, the incubation temperature increased rates of mineralization and humification, whereas lower temperatures limited the extent of both processes. In these soils the addition of co-compost in spring or summer is the most recommendable. In soils with HA of lower E(4)/E(6) ratio (<5), the higher temperature favoured mineralization but not humification, whereas the low temperature maintained the SOC levels and even increased the HA/FA ratio. In these soils the moment of addition of organic amendment should be decided depending on the effect intended. On the other hand, the lower the SOC

Crop response to localized organic amendment in soils with limiting physical properties

NASA Astrophysics Data System (ADS)

Lordan, Joan; Pascual, Miquel; Fonseca, Francisco; Villar, Josep Maria; Montilla, Victor; Papió, Josep; Rufat, Josep

2013-04-01

This 2-year study evaluated the use of rice husk as a localized organic amendment in a soil with limiting physical properties. The research was conducted in a commercial peach orchard planted in 2011 using a ridge planting system. Six soil and water management treatments were evaluated in 18 experimental units, which were set up in the field using a randomized complete block design. The treatments were compared both in terms of soil physical properties and crop response. Soil amendment with rice husk was the most effective technique. It improved soil conditions (soil infiltration and soil porosity), providing a better soil environment for root activity and thereby resulted in better crop performance. Concerning growth parameters, the amended treatment presented the highest overall values without negatively affecting crop water status. These techniques were suitable for mitigating the effects of soils with limiting physical conditions. Localized applications of amendments, as proposed in this work, imply an important reduction in application rates. It is important to consider an efficient use of by-products since there is a growing interest in industrial and agronomical exploitations.

Arsenic bioaccessibility and speciation in the soils amended with organoarsenicals and drinking-water treatment residuals based on a long-term greenhouse study

NASA Astrophysics Data System (ADS)

Nagar, Rachana; Sarkar, Dibyendu; Makris, Konstantinos C.; Datta, Rupali

2014-10-01

SummaryAlthough organoarsenical pesticides are no longer applied to agricultural fields in the US, their widespread use until recently, toxicity, and potential transformation to inorganic arsenic has raised serious concern. Drinking-water treatment residuals (WTRs) have been proposed as a low-cost amendment for remediation of organoarsenical pesticide contaminated soils. A long-term greenhouse study was initiated to evaluate the effect WTR application on bioaccessibility, geochemical partitioning, and speciation of the Dimethylarsinic acid (DMA). Two soils (Immokalee and Orelia series) were spiked with DMA (1500 mg As kg-1) and amended with an Al- and Fe-based WTR at two rates (5% and 10% by wt.). Soil sampling was done immediately after spiking (time zero) and after 0.25, 0.5, 1, and 3 (time final) years of equilibration and subjected to bioaccessibility test and sequential extraction. Results showed that compared to the unamended (no WTR) control, As bioaccessibility in the WTR-amended soils significantly (p < 0.001) decreased by 40-70% in 3 years. The Fe-WTR was more effective than Al-WTR in decreasing soil As bioaccessibility. The in vitro and water-extracted samples were subjected to As speciation at time zero and time final. Results showed transformation of DMA into inorganic As, irrespective of WTR amendments. The Orelia soil showed significantly (p < 0.001) higher transformation than the Immokalee soil.

Sorption of polar herbicides and herbicide metabolites by biochar-amended soil.

PubMed

Dechene, Annika; Rosendahl, Ingrid; Laabs, Volker; Amelung, Wulf

2014-08-01

Biochar-amended soil has been proven to possess superior sorption capacities for several environmental pollutants compared with pure soil. However, the role of biochar in the immobilization of polar pesticides and their metabolites has hardly been tested. The aim of this study was therefore to investigate the effect of a soil amendment with biochar on the sorption of selected polar herbicides and herbicide metabolites (log Kow 0.3-<2). To simulate worst-case sorption, a sandy soil (1.7% organic matter) was amended with 1.5% biochar (fresh or composted) to determine sorption/desorption isotherms of the test compounds. One herbicide (imazamox) and three herbicide metabolites (methyl-desphenyl-chloridazon, metazachlor oxalic acid, metazachlor sulfonic acid) were tested, i.e. three anionic and one neutral polar compound. The results showed that the presence of biochar increased the sorption capacity of the soil only in the case of the uncharged compound methyl-desphenyl-chloridazon, for which the average distribution coefficients in biochar-amended soils were higher than in pure soil by a factor of 2.1-2.5. However, this effect rather seemed to reflect the increased soil organic carbon content after the addition of biochar than a preferred sorption of methyl-desphenyl-chloridazon to biochar. In the case of the three anionic compounds imazamox, metazachlor oxalic acid and metazachlor sulfonic acid, biochar amendment did not increase the sorption capacity of the soil for these compounds, presumably as a result of its negative net charge. Similarly, desorption experiments did not show any significant effect of the biochar amendment on desorption. This suggests that the potential of using biochar to mitigate the leaching of the tested polar pesticides or metabolites is limited. Copyright © 2014 Elsevier Ltd. All rights reserved.

Soil management: The key to soil quality and sustainable agriculture

NASA Astrophysics Data System (ADS)

Basch, Gottlieb; Barão, Lúcia; Soares, Miguel

2017-04-01

Today, after the International Year of Soils in 2015 and the proclamation by the International Union of Soil Sciences of the International Decade of Soils 2015-2020, much attention is paid to soil quality. Often used interchangeably, both terms, soil quality and soil health, refer to dynamic soil properties such as soil organic matter or pH, while soil quality also includes inherent soil properties such as texture or mineral composition. However, it is the dynamic or manageable properties that adequate soil management can influence and thus contribute to a well-functioning soil environment capable to deliver the soil-mediated provisioning, regulating and supporting ecosystem services and soil functions. This contribution intends to highlight the key principles of sustainable soil management and provide evidence that they are compliant with a productive, resource efficient and ecologically friendly agriculture. Paradoxically, and despite benefitting from good soil quality, agriculture itself when based on conventional, especially intensive tillage-based soil management practices contributes decisively to soil degradation and to several of the soil threats as identified by the Soil Thematic Strategy, being soil erosion and soil organic matter decline the most notorious ones. To mitigate soil degradation, the European Union's Common Agricultural Policy has introduced conservation measures, mainly through cross-compliance measures supposed to guarantee minimum soil cover, to limit soil erosion and to maintain the levels of soil organic matter. However, it remains unclear to what extent EU member states apply these 'Good Agricultural and Environmental Condition' (GAEC) measures to their utilized agricultural areas. Effective and cost-efficient soil management systems able to conserve or to restore favourable soil conditions, to minimize soil erosion and to invert soil organic matter and soil biodiversity decline and improve soil structure are those capable to mimic as

Petition for Rulemaking to Amend Agricultural Worker Protection Standard Effective Date

EPA Pesticide Factsheets

This petition from the National Association of State Departments of Agriculture and the American Farm Bureau Federation, dated December 21, 2016, asks that the Agency amend the Agricultural Worker Protection Standard by postponing the effective date.

Populations of Pratylenchus penetrans Relative to Decomposing Nitrogenous Soil Amendments

PubMed Central

Walker, J. T.

1971-01-01

Populations of Pratylenchus penetrans decreased in soil following addition of 70 and 700 ppm N in the form of nitrate, nitrite, organic nitrogen, or ammonium compounds. Nitrate was less effective than other nitrogen carriers. Population reduction is principally attributed to ammonification during decomposition. This hypothesis is supported by chromatographic analyses of soil atmospheres, survival of nematodes in pure CO₂ and N₂, inverse relationship of CO₂, content in amended soils to nematode populations, and direct relationship of NH₃-N content of amended soils to nematode populations. PMID:19322339

Metagenomic analysis of soil and freshwater from zoo agricultural area with organic fertilization

PubMed Central

Meneghine, Aylan K.; Nielsen, Shaun; Thomas, Torsten; Carareto Alves, Lucia Maria

2017-01-01

Microbial communities drive biogeochemical cycles in agricultural areas by decomposing organic materials and converting essential nutrients. Organic amendments improve soil quality by increasing the load of essential nutrients and enhancing the productivity. Additionally, fresh water used for irrigation can affect soil quality of agricultural soils, mainly due to the presence of microbial contaminants and pathogens. In this study, we investigated how microbial communities in irrigation water might contribute to the microbial diversity and function of soil. Whole-metagenomic sequencing approaches were used to investigate the taxonomic and the functional profiles of microbial communities present in fresh water used for irrigation, and in soil from a vegetable crop, which received fertilization with organic compost made from animal carcasses. The taxonomic analysis revealed that the most abundant genera were Polynucleobacter (~8% relative abundance) and Bacillus (~10%) in fresh water and soil from the vegetable crop, respectively. Low abundance (0.38%) of cyanobacterial groups were identified. Based on functional gene prediction, denitrification appears to be an important process in the soil community analysed here. Conversely, genes for nitrogen fixation were abundant in freshwater, indicating that the N-fixation plays a crucial role in this particular ecosystem. Moreover, pathogenicity islands, antibiotic resistance and potential virulence related genes were identified in both samples, but no toxigenic genes were detected. This study provides a better understanding of the community structure of an area under strong agricultural activity with regular irrigation and fertilization with an organic compost made from animal carcasses. Additionally, the use of a metagenomic approach to investigate fresh water quality proved to be a relevant method to evaluate its use in an agricultural ecosystem. PMID:29267397

Kinetic characteristic of phenanthrene sorption in aged soil amended with biochar

NASA Astrophysics Data System (ADS)

Kim, Chanyang; Kim, Yong-Seong; Hyun, Seunghun

2015-04-01

Biochar has been recently highlighted as an amendment that affects yield of the crops by increasing pH, cation exchange capacity and water retention, and reduces the lability of contaminants by increasing sorption capacity in the soil system. Biochar's physico-chemical properties, high CEC, surfaces containing abundant micropores and macropores, and various types of functional groups, play important roles in enhancing sorption capacity of contaminants. Aging through a natural weathering process might change physico-chemical properties of biochar amended in soils, which can affect the sorption behavior of contaminants. Thus, in this study, the sorption characteristics of phenanthrene (PHE) on biochar-amended soils were studied with various types of chars depending on aging time. To do this, 1) soil was amended with sludge waste char (SWC), wood char (WC), and municipal waste char (MWC) during 0, 6, and 12 month. Chars were applied to soil at 1% and 2.5% (w/w) ratio. 2) Several batch kinetic and equilibrium studies were conducted. One-compartment first order and two-compartment first order model apportioning the fraction of fast and slow sorbing were selected for kinetic models. Where, qt is PHE concentration in biochar-amended soils at each time t, qeis PHE concentration in biochar-amended soils at equilibrium. ff is fastly sorbing fraction and (1-ff) is slowly sorbing fraction. k is sorption rate constant from one-compartment first order model, k1 and k2 are sorption rate constant from two-compartment first order model, t is time (hr). The equilibrium sorption data were fitted with Fruendlich and Langmuir equation. 3) Change in physico-chemical properties of biochar-amended soils was investigated with aging time. Batch equilibrium sorption results suggested that sorbed amount of PHE on WC was greater than SWC and MWC. The more char contents added to soil, the greater sorption capacity of PHE. Sorption equilibrium was reached after 4 hours and equilibrium pH ranged

Assessing the probability of infection by Salmonella due to sewage sludge use in agriculture under several exposure scenarios for crops and soil ingestion.

PubMed

Krzyzanowski, Flávio; de Souza Lauretto, Marcelo; Nardocci, Adelaide Cássia; Sato, Maria Inês Zanoli; Razzolini, Maria Tereza Pepe

2016-10-15

A deeper understanding about the risks involved in sewage sludge practice in agriculture is required. The aims of the present study were to determine the annual risk of infection of consuming lettuce, carrots and tomatoes cultivated in soil amended with sewage sludge. The risk to agricultural workers of accidental ingestion of sludge or amended soil was also investigated. A Quantitative Microbial Risk Assessment was conducted based on Salmonella concentrations from five WWTPs were used to estimate the probability of annual infection associated with crops and soil ingestion. The risk of infection was estimated for nine exposure scenarios considering concentration of the pathogen, sewage sludge dilution in soil, variation of Salmonella concentration in soil, soil attachment to crops, seasonal average temperatures, hours of post-harvesting exposure, Salmonella regrowth in lettuce and tomatoes, Salmonella inhibition factor in carrots, crop ingestion and frequency of exposure, sludge/soil ingestion by agricultural workers and frequency of exposure. Annual risks values varied across the scenarios evaluated. Highest values of annual risk were found for scenarios in which the variation in the concentration of Salmonella spp. in both soil and crops (scenario 1) and without variation in the concentration of Salmonella spp. in soil and variation in crops (scenario 3) ranging from 10(-3) to 10(-2) for all groups considered. For agricultural workers, the highest annual risks of infection were found when workers applied sewage sludge to agricultural soils (2.26×10(-2)). Sensitivity analysis suggests that the main drivers for the estimated risks are Salmonella concentration and ingestion rate. These risk values resulted from conservative scenarios since some assumptions were derived from local or general studies. Although these scenarios can be considered conservative, the sensitivity analysis yielded the drivers of the risks, which can be useful for managing risks from the

Seasonal dynamics of CO2 efflux in soils amended with composted and thermally-dried sludge as affected by soil tillage systems in a semi-arid agroecosystem

NASA Astrophysics Data System (ADS)

García-Gil, Juan Carlos; Soler-Rovira, Pedro; López-de-Sa, Esther G.; Polo, Alfredo

2014-05-01

In semi-arid agricultural soils, seasonal dynamic of soil CO2 efflux (SCE) is highly variable. Based on soil respiration measurements the effects of different management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) was investigated in a long-term field experiment (28 years) conducted on a sandy-loam soil at the experimental station 'La Higueruela' (40o 03'N, 4o 24'W). Both organic amendments were applied at a rate of 30 Mg ha-1 prior to tillage practices. Unamended soils were used as control for each tillage system. SCE was moderate in late spring (2.2-11.8 μmol CO2 m-2 s-1) when amendments were applied and tillage was performed, markedly decreased in summer (0.4-3.2 μmol CO2 m-2 s-1), following a moderate increase in autumn (3.4-14.1 μmol CO2 m-2 s-1), rising sharply in October (5.6-39.8 μmol CO2 m-2 s-1 ). In winter, SCE was low (0.6-6.5 μmol CO2 m-2 s-1). In general, SCE was greater in chisel and moldboard tilled soils, and in CS and particularly TSS-amended soils, due to the addition of labile C with these amendments, meanwhile no-tillage soils exhibited smaller increases in C efflux throughout the seasons. Soil temperature controlled the seasonal variations of SCE. In summer, when drought occurs, a general decrease of SCE was observed due to a deficit in soil water content. After drought period SCE jumped to high values in response to rain events ('Birch effect') that changed soil moisture conditions. Soil drying in summer and rewetting in autumn may promotes some changes on the structure of soil microbial community, affecting associated metabolic processes, and enhancing a rapid mineralization of water-soluble organic C compounds and/or dead microbial biomass that acts as an energy source for soil microorganisms. To assess the effects of tillage and amendments on SCE, Q10 values were calculated. Data were grouped into three groups according to soil moisture (0

Cadmium contamination of agricultural soils and crops resulting from sphalerite weathering.

PubMed

Robson, T C; Braungardt, C B; Rieuwerts, J; Worsfold, P

2014-01-01

The biogeochemistry and bioavailability of cadmium, released during sphalerite weathering in soils, were investigated under contrasting agricultural scenarios to assess health risks associated with sphalerite dust transport to productive soils from mining. Laboratory experiments (365 d) on temperate and sub-tropical soils amended with sphalerite (<63 μm, 0.92 wt.% Cd) showed continuous, slow dissolution (0.6-1.2% y(-1)). Wheat grown in spiked temperate soil accumulated ≈38% (29 μmol kg(-1)) of the liberated Cd, exceeding food safety limits. In contrast, rice grown in flooded sub-tropical soil accumulated far less Cd (0.60 μmol kg(-1)) due to neutral soil pH and Cd bioavailability was possibly also controlled by secondary sulfide formation. The results demonstrate long-term release of Cd to soil porewaters during sphalerite weathering. Under oxic conditions, Cd may be sufficiently bioavailable to contaminate crops destined for human consumption; however flooded rice production limits the impact of sphalerite contamination. Copyright © 2013 Elsevier Ltd. All rights reserved.

How agricultural management shapes soil microbial communities: patterns emerging from genetic and genomic studies

NASA Astrophysics Data System (ADS)

Daly, Amanda; Grandy, A. Stuart

2016-04-01

Agriculture is a predominant land use and thus a large influence on global carbon (C) and nitrogen (N) balances, climate, and human health. If we are to produce food, fiber, and fuel sustainably we must maximize agricultural yield while minimizing negative environmental consequences, goals towards which we have made great strides through agronomic advances. However, most agronomic strategies have been designed with a view of soil as a black box, largely ignoring the way management is mediated by soil biota. Because soil microbes play a central role in many of the processes that deliver nutrients to crops and support their health and productivity, agricultural management strategies targeted to exploit or support microbial activity should deliver additional benefits. To do this we must determine how microbial community structure and function are shaped by agricultural practices, but until recently our characterizations of soil microbial communities in agricultural soils have been largely limited to broad taxonomic classes due to methodological constraints. With advances in high-throughput genetic and genomic sequencing techniques, better taxonomic resolution now enables us to determine how agricultural management affects specific microbes and, in turn, nutrient cycling outcomes. Here we unite findings from published research that includes genetic or genomic data about microbial community structure (e.g. 454, Illumina, clone libraries, qPCR) in soils under agricultural management regimes that differ in type and extent of tillage, cropping selections and rotations, inclusion of cover crops, organic amendments, and/or synthetic fertilizer application. We delineate patterns linking agricultural management to microbial diversity, biomass, C- and N-content, and abundance of microbial taxa; furthermore, where available, we compare patterns in microbial communities to patterns in soil extracellular enzyme activities, catabolic profiles, inorganic nitrogen pools, and nitrogen

Sorption and leaching of benzalkonium chlorides in agricultural soils.

PubMed

Khan, Adnan Hossain; Macfie, Sheila M; Ray, Madhumita B

2017-07-01

The adsorption and leaching characteristics of two commonly used benzalkonium chlorides (BACs), benzyl dimethyl dodecyl ammonium chloride (BDDA) and benzyl dimethyl tetradecyl ammonium chloride (BDTA) using three agricultural soils with varied proportions of silt, sand, clay, and organic matter were determined. BACs are cationic surfactants used in large quantities for sanitary and personal care products and are abundant in environmental samples. Adsorption isotherm data (aqueous concentration in the range of 25-150 mg L -1 ) fitted the Langmuir model better than the Freundlich model. BDTA with a longer alkyl chain adsorbed more to soil compared to BDDA, and the soil with the highest percentage of clay adsorbed the most. Column tests conducted using soils amended with lime stabilised biosolids and artificial rain water at a flow rate of 0.2 mL min -1 indicate very low leaching of BACs. Less than 1% of the available BDDA leached through sandy loam soil column with a depth of 9 cm. Therefore, the possibility of BACs to become bioavailable through leaching is very low at environmentally relevant concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Metolachlor Sorption and Degradation in Soil Amended with Fresh and Aged Biochars.

PubMed

Trigo, Carmen; Spokas, Kurt A; Hall, Kathleen E; Cox, Lucia; Koskinen, William C

2016-04-27

Addition of organic amendments such as biochar to soils can influence pesticide sorption-desorption processes and, in turn, the amount of pesticide readily availability for transport and biodegradation. Sorption-desorption processes are affected by both the physical and chemical properties of soils and pesticides, as well as soil-pesticide contact time, or aging. Changes in sorption-desorption of metolachlor with aging in soil amended with three macadamia nut shell biochars aged 0 (BCmac-fr), 1 year (BCmac-1yr), and 2 years (BCmac-2yr) and two wood biochars aged 0 (BCwood-fr) and 5 years (BCwood-5yr) were determined. Apparent sorption coefficient (Kd-app) values increased with incubation time to a greater extent in amended soil as compared to unamended soils; Kd-app increased by 1.2-fold for the unamended soil, 2.0-fold for BCwood-fr, 1.4-fold for BCwood-5yr, 2.4-fold for BCmac-fr, 2.5-fold for BCmac-1yr, and 1.9-fold for BCmac-4yr. The increase in calculated Kd-app value was the result of a 15% decrease in the metolachlor solution concentration extractable with CaCl2 solution with incubation time in soil as compared to a 50% decrease in amended soil with very little change in the sorbed concentration. Differences could possibly be due to diffusion to less accessible or stronger binding sites with time, a faster rate of degradation (in solution and on labile sites) than desorption, or a combination of the two in the amended soils. These data show that transport models would overpredict the depth of movement of metolachlor in soil if effects of aging or biochar amendments are not considered.

Influence of biochar amendments on the sorption-desorption of aminocyclopyrachlor, bentazone and pyraclostrobin pesticides to an agricultural soil

USDA-ARS?s Scientific Manuscript database

The many advantageous properties of biochar have led to the recent interest in the use of this carbonaceous material as a soil amendment. However, there are limited studies dealing with the effect of biochar on the behavior of pesticides applied to crops. The objective of this work was to study the ...

The effect of biochar amendment on the soil microbial community - PLFA analyses and 13C labeling results

NASA Astrophysics Data System (ADS)

Watzinger, A.; Feichtmair, S.; Rempt, F.; Anders, E.; Wimmer, B.; Kitzler, B.; Zechmeister-Boltenstern, S.; Horacek, M.; Zehetner, F.; Kloss, S.; Richoz, S.; Soja, G.

2012-04-01

The effects of biochar amendment on plant growth and on the chemical / physical soil characteristics are well explored but only few studies have investigated the impact on soil microorganisms. The response of the soil microbial community to biochar amendment was investigated by phospholipid fatty acid (PLFA) analysis in (i) a large scale pot experiment, (ii) a small scale pot experiment using 13C labeled biochar and (iii) an incubation study using 13C labeled biochar. In the large scale pot experiment, three different agricultural soils from Austria (Planosol, Cambisol, Chernozem) and four different types of biochar were investigated. In total, 25 treatments with 5 replicates each were set up and monitored over a year. The results from the pot experiments showed no significant influence of biochar amendment on the total microbial biomass in the first 100 days after biochar addition. However, discriminant analysis showed a distinction of biochar and control soils as well as a strong effect of the pyrolysis temperature on the microbial composition. The effect of biochar was dependent on the type of soil. In the Planosol, some PLFAs were affected positively, especially when adding biochar with a low pyrolysis temperature, in the first month. In the long term, microbial community composition altered. Growth of fungi and gram negative bacteria was enhanced. In the Chernozem, PLFAs from various microbial groups decreased in the long term. Variability in the incubation study was low. Consequently, many PLFAs were significantly affected by biochar amendment. Again, in the Planosol, gram negative bacteria, actinomycetes and, after 2 weeks, gram positive bacteria increased under biochar amendment whereas in the chernozem total microbial biomass and gram positive bacteria were negatively affected in the long term. The 13C labeling studies confirmed the low degradability of the biochar, i.e. no alteration of the content and the δ13C in the soil organic matter within 100 days

Effects of Biosolid Soil Amendment on Heterodera glycines Populations

PubMed Central

Melakeberhan, H; Noel, G. R.

2006-01-01

The high degree of parasitic variability in Heterodera glycines and its distribution in a wide range of soybean production systems present multiple challenges for management, which necessitate increased understanding of the biology of H. glycines. Soil amendments are being considered either as stand-alone and/or as part of integrated management approaches. A recycled municipal biosolid with nutrition supplement and liming qualities, N-Viro Soil (NVS) has potential as a multi-purpose soil amendment. In three greenhouse experiments, the effects of 0, 1.0 or 4.0 g NVS/100 cm3 of sandy loam soil on three H. glycines populations (GN1, GN2 and GN3) were investigated on soybean grown for 557 ± 68 degree-days (base 10°C). The response of the three H. glycines populations to NVS treatment varied by experiment. The overall numbers of preadult stages and cysts generally decreased with increasing levels of NVS in all experiments, and the high rate was more effective than the low rate in suppressing H. glycines numbers. This suggests that the high NVS treatment can affect the three populations in the experimental soil type under controlled conditions. Field studies to determine efficacy of the soil amendment in a wide range of environments should be initiated. PMID:19259540

Soil characteristics of sediment-amended baldcypress (Taxodium distichum) swamps of coastal Louisiana

USGS Publications Warehouse

Jiang, Ming; Middleton, Beth A.

2011-01-01

Amendments of sediment from dredging activities have played an important role in raising the elevation of sinking coastal wetlands. This study compared the soil characteristics of sediment- amended coastal swamps in the Barataria Preserve unit of Jean Lafitte National Historical Park and Preserve with natural swamps along Bayou des Familles. The sandy sediment amendments used in the coastal forests had different soil texture and characteristics than the more organic soils of the natural swamps. Three years after the application of these sediments on the sediment-amended swamps, dewatering and compaction of the sediment had occurred but the sediment still had high salinity and bulk density, and low organic matter content. The two sediment-amended swamps differed from each other in that Site 1 had a higher elevation (mean = 25 cm higher) and drier soil than Site 2. The effects of sediment in coastal forested wetlands require separate consideration from studies of salt marshes, e.g., the weight of the sediment might damage tree roots, or the amendments might influence soil stability during storms in a different way. Generally, this study suggests that shallower depths of sediment are more likely to yield environments beneficial to these sinking baldcypress swamps in coastal Louisiana.

Benefits of biochar, compost and biochar-compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil.

PubMed

Agegnehu, Getachew; Bass, Adrian M; Nelson, Paul N; Bird, Michael I

2016-02-01

Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha(-1) biochar (B)+F; 3) 25 t ha(-1) compost (Com)+F; 4) 2.5 t ha(-1) B+25 t ha(-1) Com mixed on site+F; and 5) 25 t ha(-1) co-composted biochar-compost (COMBI)+F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ(15)N and δ(13)C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO3(-)N), ammonium-nitrogen (NH4(+)-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO2 and N2O were higher from the organic-amended soils than from the fertilizer-only control. However, N2O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar-compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. Copyright © 2015. Published by Elsevier B.V.

P losses in soil columns amended with compost and digestate from municipal solid wastes

NASA Astrophysics Data System (ADS)

García-Albacete, Marta; Cartagena, M. Carmen

2013-04-01

Sludge's, manures and compost applied to agricultural soils in high quantities and long-term application to increase crop productivity, result in accumulation of soil phosphorous (P). Soluble P is directly available to algae (Sonzogni et al., 1982) and thus particularly relevant to water quality degradation. Transport of P from agricultural soils to surface waters has been linked to eutrophication in fresh water and estuaries (Sharpley and Lemunyon, 1998). Almost 50% of stored water in Spain is degraded by eutrophication processes that cause the proliferation of algae and other organisms and a decrease in oxygen content (Environmental Profile of Spain 2005). Fertilizers and biodegradable wastes application rates in agriculture are based on nitrogen requirements. This results in a P supply that is in excess of crops needs since the ratio of P to N in waste use to be greater than required by plants (Smith, 1995). While surface runoff is an important pathway of phosphorus losses from agricultural lands, significant losses can also occur via leaching thought soils. Leaching tests are important for assessing the risk of release of potential pollutants from biodegradable wastes into groundwater or surface water. Percolation tests also get information about the interaction of organic waste with soils. The study was conducted according to the percolation leaching test CEN/TS 14405 "Characterization of waste-Leaching behavior test- Up-flow percolation test" with three different soils mixed with organic wastes from msw (compost and digestato) and an inorganic fertilizer (NaH2PO4). Each soil was amended with the P sources at rates of 100 kg P ha-1. Leachates were collected and analyzed for each column for dissolved reactive P by inductively coupled plasma atomic emission spectroscopy (ICP) following USEPA Method 3050A digestion (USEPA, 1995). The fact that P sorption capacity (Xmax, PSI) of the soils was determined using Langmuiŕs isotherms and the P forms from organic

Yield, quality, and concentration of seven heavy metals in cabbage and broccoli grown in sewage sludge and chicken manure amended soil.

PubMed

Antonious, George F; Kochhar, Tejinder S; Coolong, Timothy

2012-01-01

The mobility of heavy metals from soil into the food chain and their subsequent bioaccumulation has increased the attention they receive as major environmental pollutants. The objectives of this investigation were to: i) study the impact of mixing native agricultural soil with municipal sewage sludge (SS) or chicken manure (CM) on yield and quality of cabbage and broccoli, ii) quantify the concentration of seven heavy metals (Cd, Cr, Mo, Cu, Zn, Pb, and Ni) in soil amended with SS or CM, and iii) determine bioavailability of heavy metals to cabbage leaves and broccoli heads at harvest. Analysis of the two soil amendments used in this investigation indicated that Cr, Ni, Cu, Zn, Mo, Cd, Pb, and organic matter content were significantly greater (P < 0.05) in premixed sewage sludge than premixed chicken manure. Total cabbage and broccoli yields obtained from SS and CM mixed soil were both greater than those obtained from no-mulch (bare) soil. Concentration of Ni in cabbage leaves of plants grown in soil amended with CM was low compared to plants grown in no-mulch soil. No significant differences were found in Cd and Pb accumulation between cabbage and broccoli. Concentrations of Ni, Cu, Zn, and Mo were greater in broccoli than cabbage. Total metals and plant available metals were also determined in the native and amended soils. Results indicated that the concentration of heavy metals in soils did not necessary reflect metals available to plants. Regardless of soil amendments, the overall bioaccumulation factor (BAF) of seven heavy metals in cabbage leaves and broccoli heads revealed that cabbage and broccoli were poor accumulators of Cr, Ni, Cu, Cd, and Pb (BAF <1), while BAF values were >1 for Zn and Mo. Elevated Ni and Mo bioaccumulation factor (BAF >1) of cabbage grown in chicken manure mixed soil is a characteristic that would be less favorable when cabbage is grown on sites having high concentrations of these two metals.

Impacts of zeolite, alum and polyaluminum chloride amendments mixed with agricultural wastes on soil column leachate, and CO2 and CH4 emissions.

PubMed

Murnane, J G; Fenton, O; Healy, M G

2018-01-15

This study aimed to quantify leaching losses of nitrogen (N), phosphorus (P) and carbon (C), as well as carbon dioxide (CO 2 ) and methane (CH 4 ) emissions from stored slurry, and from packed soil columns surface applied with unamended and chemically amended dairy and pig slurries, and dairy soiled water (DSW). The amendments to the slurries, which were applied individually and together, were: polyaluminum chloride (PAC) and zeolite for pig and dairy slurry, and liquid aluminium sulfate (alum) and zeolite for DSW. Application of pig slurry resulted in the highest total nitrogen (TN) and nitrate-nitrogen (NO 3 -N) fluxes (22 and 12 kg ha -1 ), whereas corresponding fluxes from dairy slurries and DSW were not significantly (p < 0.05) higher than those from the control soil. There were no significant (p < 0.05) differences in leachate N losses between unamended and amended dairy slurries, unamended and amended pig slurries, and unamended and amended DSW. There were no leachate P losses measured over the experimental duration. Total cumulative organic (TOC) and inorganic C (TIC) losses in leachate were highest for unamended dairy slurry (82 and 142 kg ha -1 ), and these were significantly (p < 0.05) reduced when amended with PAC (38 and 104 kg ha -1 ). The highest average cumulative CO 2 emissions for all treatments were measured for pig slurries (680 kg CO 2 -C ha -1 ) followed by DSW (515 kg CO 2 -C ha -1 ) and dairy slurries (486 kg CO 2 -C ha -1 ). The results indicate that pig slurry, either in raw or chemically amended form, poses the greatest environmental threat of leaching losses and gaseous emissions of CO 2 and CH 4 and, in general, amendment of wastewater with PAC, alum or zeolite, does not mitigate the risk of these losses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland

PubMed Central

Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

2018-01-01

Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon–nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable. PMID:29751652

Sludge Biochar Amendment and Alfalfa Revegetation Improve Soil Physicochemical Properties and Increase Diversity of Soil Microbes in Soils from a Rare Earth Element Mining Wasteland.

PubMed

Luo, Caigui; Deng, Yangwu; Inubushi, Kazuyuki; Liang, Jian; Zhu, Sipin; Wei, Zhenya; Guo, Xiaobin; Luo, Xianping

2018-05-11

Long-term unregulated mining of ion-adsorption clays (IAC) in China has resulted in severe ecological destruction and created large areas of wasteland in dire need of rehabilitation. Soil amendment and revegetation are two important means of rehabilitation of IAC mining wasteland. In this study, we used sludge biochar prepared by pyrolysis of municipal sewage sludge as a soil ameliorant, selected alfalfa as a revegetation plant, and conducted pot trials in a climate-controlled chamber. We investigated the effects of alfalfa revegetation, sludge biochar amendment, and their combined amendment on soil physicochemical properties in soil from an IAC mining wasteland as well as the impact of sludge biochar on plant growth. At the same time, we also assessed the impacts of these amendments on the soil microbial community by means of the Illumina Miseq sequences method. Results showed that alfalfa revegetation and sludge biochar both improved soil physicochemical properties and microbial community structure. When alfalfa revegetation and sludge biochar amendment were combined, we detected additive effects on the improvement of soil physicochemical properties as well as increases in the richness and diversity of bacterial and fungal communities. Redundancy analyses suggested that alfalfa revegetation and sludge biochar amendment significantly affected soil microbial community structure. Critical environmental factors consisted of soil available K, pH, organic matter, carbon⁻nitrogen ratio, bulk density, and total porosity. Sludge biochar amendment significantly promoted the growth of alfalfa and changed its root morphology. Combining alfalfa the revegetation with sludge biochar amendment may serve to not only achieve the revegetation of IAC mining wasteland, but also address the challenge of municipal sludge disposal by making the waste profitable.

How can soil organic carbon stocks in agriculture be maintained or increased?

NASA Astrophysics Data System (ADS)

Don, Axel; Leifeld, Jens

2015-04-01

CO2 emissions from soils are 10 times higher than anthropogenic CO2 emissions from fossil burning with around 60 Pg C a-1. At the same time around 60 Pg of carbon is added to the soils as litter from roots and leaves. Thus, the balance between both fluxes is supposed to be zero for the global earth system in steady state without human perturbations. However, the global carbon flux has been altered by humans since thousands of years by extracting biomass carbon as food, feed and fiber with global estimate of 40% of net primary productivity (NPP). This fraction is low in forests but agricultural systems, in particular croplands, are systems with a high net exported carbon fraction. Soils are mainly input driven systems. Agricultural soils depend on input to compensate directly for i) respiration losses, ii) extraction of carbon (and nitrogen) and depletion (e.g. via manure) or indirectly via enhances NPP (e.g. via fertilization management). In a literature review we examined the role of biomass extraction and carbon input via roots, crop residues and amendments (manure, slurry etc.) to agricultural soil's carbon stocks. Recalcitrance of biomass carbon was found to be of minor importance for long-term carbon storage. Thus, also the impact of crop type on soil carbon dynamics seems mainly driven by the amount of crop residuals of different crop types. However, we found distinct differences in the efficiency of C input to refill depleted soil C stocks between above ground C input or below ground root litter C input, with root-C being more efficient due to slower turnover rates. We discuss the role of different measures to decrease soil carbon turnover (e.g. decreased tillage intensity) as compared to measures that increase C input (e.g. cover crops) in the light of global developments in agricultural management with ongoing specialization and segregation between catch crop production and dairy farms.

Simazine application inhibits nitrification and changes the ammonia-oxidizing bacterial communities in a fertilized agricultural soil.

PubMed

Hernández, Marcela; Jia, Zhongjun; Conrad, Ralf; Seeger, Michael

2011-12-01

s-Triazine herbicides are widely used for weed control, and are persistent in soils. Nitrification is an essential process in the global nitrogen cycle in soil, and involves ammonia-oxidizing Bacteria (AOB) and ammonia-oxidizing Archaea (AOA). In this study, we evaluated the effect of the s-triazine herbicide simazine on the nitrification and on the structure of ammonia-oxidizing microbial communities in a fertilized agricultural soil. The effect of simazine on AOB and AOA were studied by PCR-amplification of amoA genes of nitrifying Bacteria and Archaea in soil microcosms and denaturing gradient gel electrophoresis (DGGE) analyses. Simazine [50 μg g(-1) dry weight soil (d.w.s)] completely inhibited the nitrification processes in the fertilized agricultural soil. The inhibition by simazine of ammonia oxidation observed was similar to the reduction of ammonia oxidation by the nitrification inhibitor acetylene. The application of simazine-affected AOB community DGGE patterns in the agricultural soil amended with ammonium, whereas no significant changes in the AOA community were observed. The DGGE analyses strongly suggest that simazine inhibited Nitrosobacteria and specifically Nitrosospira species. In conclusion, our results suggest that the s-triazine herbicide not only inhibits the target susceptible plants but also inhibits the ammonia oxidation and the AOB in fertilized soils. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Mobility of selected trace elements in Mediterranean red soil amended with phosphogypsum: experimental study.

PubMed

Kassir, Lina Nafeh; Darwish, Talal; Shaban, Amin; Ouaini, Naim

2012-07-01

Soil amendment by phosphogypsum (PG) application becomes of increasing importance in agriculture. This may lead, however, to soil, plant, and groundwater contamination with trace elements (TEs) inherently present in PG. Monitoring of selected TEs (Pb, Zn, Cu, and Cd) distribution and mobility in a Mediterranean red soil profile has been performed in soil parcels applied with PG over a 16-month period. Concentrations were measured in soil and plant samples collected from various depth intervals at different points in time. TEs sequential extraction was performed on soil and PG samples. Results showed soil profile enrichment peaked 5 months after PG application for Cd, and 12 months for Pb, Zn, and Cu. Rainwater, pH, total organic carbon, and cationic exchange capacity were the main controlling factors in TEs accumulation in soils. Cd was transferred to a soil depth of about 20 cm. Zn exhibited mobility towards deeper layers. Pb and Cu were accumulated in around 20-55-cm-deep layers. PG increased the solubility of the studied TEs; PG-applied soils contained TEs bound to exchangeable and acid-soluble fractions in higher percentages than reference soil. Pb, Zn, and Cu were sorbed into mineral soil phases, while Cd was mainly found in the exchangeable (bio-available) form. The order of TEs decreasing mobility was Zn > Cd > Pb > Cu. Roots and leaves of existed plants, Cichorium intybus L., accumulated high concentrations of Cd (1-2.4 mg/kg), exceeding recommended tolerable levels, and thus signifying potential health threats through contaminated crops. It was therefore recommended that PG should be applied in carefully established, monitored, and controlled quantities to agricultural soils.

EVALUATION OF A SOIL AMENDMENT PROCESS DEMONSTRATION FOR REDUCING THE BIOAVAILABILITY OF LEAD

EPA Science Inventory

The USEPA evaluated an in situ application of a soil amendment process at a residential site that was contaminated with lead. The goal of the evaluation was to determine if the soil amendment process resulted in lower concentrations of bioavailable lead in the contaminated soils...

Soil amendments yield persisting effects on the microbial communities--a 7-year study

USDA-ARS?s Scientific Manuscript database

Soil microbial communities are sensitive to carbon amendments and largely control the decomposition and accumulation of soil organic matter. In this study, we evaluated whether the type of carbon amendment applied to wheat-cropped or fallow soil imparted lasting effects on the microbial community w...

Organic and inorganic amendment application on mercury-polluted soils: effects on soil chemical and biochemical properties.

PubMed

García-Sánchez, Mercedes; Klouza, Martin; Holečková, Zlata; Tlustoš, Pavel; Száková, Jiřina

2016-07-01

On the basis of a previous study performed in our laboratory, the use of organic and inorganic amendments can significantly modify the Hg mobility in soil. We have compared the effectiveness of organic and inorganic amendments such as digestate and fly ash, respectively, reducing the Hg mobility in Chernozem and Luvisol soils differing in their physicochemical properties. Hence, the aim of this work was to compare the impact of digestate and fly ash application on the chemical and biochemical parameters in these two mercury-contaminated soils in a model batch experiment. Chernozem and Luvisol soils were artificially contaminated with Hg and then incubated under controlled conditions for 21 days. Digestate and fly ash were applied to both soils in a dose of 10 and 1.5 %, respectively, and soil samples were collected after 1, 7, 14, and 21 days of incubation. The presence of Hg in both soils negatively affected to processes such as nitrification, provoked a decline in the soil microbial biomass C (soil microbial biomass C (MBC)), and the microbial activities (arylsulfatase, and β-glucosaminidase) in both soils. Meanwhile, the digestate addition to Chernozem and Luvisol soils contaminated with Hg improved the soil chemical properties (pH, dissolved organic carbon (DOC), N (Ntot), inorganic-N forms (N-NH4 (+) and N-NO3 (-))), as consequence of high content in C and N contained in digestate. Likewise, the soil MBC and soil microbial activities (dehydrogenase, arylsulfatase, and β-glucosaminidase) were greatly enhanced by the digestate application in both soils. In contrast, fly ash application did not have a remarkable positive effect when compared to digestate in Chernozem and Luvisol soil contaminated with mercury. These results may indicate that the use of organic amendments such as digestate considerably improved the soil health in Chernozem and Luvisol compared with fly ash, alleviating the detrimental impact of Hg. Probably, the chemical properties present in

Impact of Distillery Spent Wash Irrigation on Agricultural Soil

NASA Astrophysics Data System (ADS)

Jadhav, Ramanand N.; Sarode, Dhananjay B.; Narkhede, Sachin D.; Khatik, Vasimshaikh A.; Attarde, Sanjay B.

2011-07-01

The disposal of wastes from industrial sources is becoming a serious problem throughout the world. In India, a total of approximately 40 million m3 of distillery spent wash is generated annually from 295 distilleries. The distillery spent wash is acidic and high levels of biological oxygen demand and chemical oxygen demand and contains nutrient elements such as potassium (K), nitrogen (N), and phosphorous (P). It is used as a source of plant nutrients and organic matter for various agricultural crops. It is usually applied to arable land near the distilleries as irrigation water or as a soil amendment. However, indiscriminate disposal of it has resulted in adverse impact on soil environments. This paper aims to identify the impact of distillery spent wash application for irrigation and on soil environment. The distillery spent wash can be a good source of nutrients necessary for plant growth. Application of various concentrations of spent wash on plant species was studied. A plot having 20-30% concentration of spent wash observed good growth. At higher doses, spent wash application is found harmful to crop growth and soil fertility and its use at lower doses remarkably improves germination and growth of crops.

ADSORPTION OF CADMIUM ONTO DIFFERENT FRACTIONS OF BIOSOLID-AMENDED SOILS

EPA Science Inventory

We hypothesized not only organic but also inorganic fraction in biosolids controls the metal availability in soil systems. To test this hypothesis we conducted Cd adsorption experiments on different fractions of biosolids, biosolid amended soils, and unamended soils. Soils were c...

Cadmium Sorption Characteristics of Soil Amendments and its Relationship with the Cadmium Uptake by Hyperaccumulator and Normal Plants in Amended Soils

PubMed Central

Sun, Yan; Wu, Qi-Tang; Lee, Charles C.C.; Li, Baoqin; Long, Xinxian

2013-01-01

In order to select appropriate amendments for cropping hyperaccumulator or normal plants on contaminated soils and establish the relationship between Cd sorption characteristics of soil amendments and their capacity to reduce Cd uptake by plants, batch sorption experiments with 11 different clay minerals and organic materials and a pot experiment with the same amendments were carried out. The pot experiment was conducted with Sedum alfredii and maize (Zea mays) in a co-cropping system. The results showed that the highest sorption amount was by montmorillonite at 40.82 mg/g, while mica was the lowest at only 1.83 mg/g. There was a significant negative correlation between the n value of Freundlich equation and Cd uptake by plants, and between the logarithm of the stability constant K of the Langmuir equation and plant uptake. Humic acids (HAs) and mushroom manure increased Cd uptake by S. alfredii, but not maize, thus they are suitable as soil amendments for the co-cropping S. alfredii and maize. The stability constant K in these cases was 0.14–0.16 L/mg and n values were 1.51–2.19. The alkaline zeolite and mica had the best fixation abilities and significantly decreased Cd uptake by the both plants, with K ≥ 1.49 L/mg and n ≥ 3.59. PMID:24912231

Soil physical and hydrological properties as affected by long-term addition of various organic amendments

NASA Astrophysics Data System (ADS)

Eden, Marie; Völkel, Jörg; Mercier, Vincent; Labat, Christophe; Houot, Sabine

2014-05-01

The use of organic residues as soil amendments in agriculture not only reduces the amount of waste needing to be disposed of; it may also lead to improvements in soil properties, including physical and hydrological ones. The present study examines a long-term experiment called "Qualiagro", run jointly by INRA and Veolia Environment in Feucherolles, France (near Paris). It was initiated in 1998 on a loess-derived silt loam (787 g/kg silt, 152 g/kg clay) and includes ten treatments: four types of organic amendments and a control (CNT) each at two levels of mineral nitrogen (N) addition: minimal (Nmin) and optimal (Nopt). The amendments include three types of compost and farmyard manure (FYM), which were applied every other year at a rate of ca. 4 t carbon ha-1. The composts include municipal solid waste compost (MSW), co-compost of green wastes and sewage sludge (GWS), and biowaste compost (BIO). The plots are arranged in a randomized block design and have a size of 450 m²; each treatment is replicated four times (total of 40 plots). Ca. 15 years after the start of the experiment soil organic carbon (OC) had continuously increased in the amended plots, while it remained stable or decreased in the control plots. This compost- or manure-induced increase in OC plays a key role, affecting numerous dependant soil properties like bulk density, porosity and water retention. The water holding capacity (WHC) of a soil is of particular interest to farmers in terms of water supply for plants, but also indicates soil quality and functionality. Addition of OC may affect WHC in different ways: carbon-induced aggregation may increase larger-pore volume and hence WHC at the wet end while increased surface areas may lead to an increased retention of water at the dry end. Consequently it is difficult to predict (e.g. with pedotransfer functions) the impact on the amount of water available for plants (PAW), which was experimentally determined for the soils, along with the entire range

Effect of Soil Amendments on Microbial Resilience Capacity of Acid Soil Under Copper Stress.

PubMed

Mounissamy, Vassanda Coumar; Kundu, Samaresh; Selladurai, Rajendiran; Saha, Jayanta Kumar; Biswas, Ashish Kumar; Adhikari, Tapan; Patra, Ashok Kumar

2017-11-01

An incubation study was undertaken to study microbial resilience capacity of acid soil amended with farmyard manure (FYM), charcoal and lime under copper (Cu) perturbation. Copper stress significantly reduced enzymatic activities and microbial biomass carbon (MBC) in soil. Percent reduction in microbial activity of soil due to Cu stress was 74.7% in dehydrogenase activity, 59.9% in MBC, 48.2% in alkaline phosphatase activity and 15.1% in acid phosphatase activity. Soil treated with FYM + charcoal showed highest resistance index for enzymatic activities and MBC. Similarly, the highest resilience index for acid phosphatase activity was observed in soil amended with FYM (0.40), whereas FYM + charcoal-treated soil showed the highest resilience indices for alkaline, dehydrogenase activity and MBC: 0.50, 0.22 and 0.25, respectively. This investigation showed that FYM and charcoal application, either alone or in combination, proved to be better than lime with respect to microbial functional resistance and resilience of acid soil under Cu perturbation.

Field dissipation and risk assessment of typical personal care products TCC, TCS, AHTN and HHCB in biosolid-amended soils.

PubMed

Chen, Feng; Ying, Guang-Guo; Ma, Yi-Bing; Chen, Zhi-Feng; Lai, Hua-Jie; Peng, Feng-Jiao

2014-02-01

The antimicrobial agents triclocarban (TCC) and triclosan (TCS) and synthetic musks AHTN (Tonalide) and HHCB (Galaxolide) are widely used in many personal care products. These compounds may release into the soil environment through biosolid application to agricultural land and potentially affect soil organisms. This paper aimed to investigate accumulation, dissipation and potential risks of TCC, TCS, AHTN and HHCB in biosolid-amended soils of the three field trial sites (Zhejiang, Hunan and Shandong) with three treatments (CK: control without biosolid application, T1: single biosolid application, T2: repeated biosolid application every year). The one-year monitoring results showed that biosolids application could lead to accumulation of these four chemicals in the biosolid-amended soils, with the residual concentrations in the following order: TCC>TCS>AHTN>HHCB. Dissipation of TCC, TCS, AHTN and HHCB in the biosolid-amended soils followed the first-order kinetics model. Half-lives for TCC, TCS, AHTN and HHCB under the field conditions of Shandong site were 191, 258, 336 and 900 days for T1, and 51, 106, 159 and 83 days for T2, respectively. Repeated applications of biosolid led to accumulation of these personal care products and result in higher ecological risks. Based on the residual levels in the trial sites and limited toxicity data, high risks to soil organisms are expected for TCC and TCS, while low-medium risks for AHTN and HHCB. © 2013.

Influence of soil amendments made from digestate on soil physics and the growth of spring wheat

NASA Astrophysics Data System (ADS)

Dietrich, Nils; Knoop, Christine; Raab, Thomas; Krümmelbein, Julia

2016-04-01

Every year 13 million tons of organic wastes accumulate in Germany. These wastes are a potential alternative for the production of energy in biogas plants, especially because the financial subventions for the cultivation of renewable resources for energy production were omitted in 2014. The production of energy from biomass and organic wastes in biogas plants results in the accumulation of digestate and therefore causes the need for a sustainable strategy of the utilization of these residues. Within the scope of the BMBF-funded project 'VeNGA - Investigations for recovery and nutrient use as well as soil and plant-related effects of digestate from waste fermentation' the application of processed digestate as soil amendments is examined. Therefore we tested four different mechanical treatment processes (rolled pellets, pressed pellets, shredded compost and sieved compost) to produce soil amendments from digestate with regard to their impact on soil physics, soil chemistry and the interactions between plants and soil. Pot experiments with soil amendments were performed in the greenhouse experiment with spring wheat and in field trials with millet, mustard and forage rye. After the first year of the experiment, preliminary results indicate a positive effect of the sieved compost and the rolled pellets on biomass yield of spring wheat as compared to the other variations. First results from the Investigation on soil physics show that rolled pellets have a positive effect on the soil properties by influencing size and distribution of pores resulting in an increased water holding capacity. Further ongoing enhancements of the physical and chemical properties of the soil amendments indicate promising results regarding the ecological effects by increased root growth of spring wheat.

Radical change of Zn speciation in pig slurry amended soil: Key role of nano-sized sulfide particles.

PubMed

Formentini, Thiago Augusto; Legros, Samuel; Fernandes, Cristovão Vicente Scapulatempo; Pinheiro, Adilson; Le Bars, Maureen; Levard, Clément; Mallmann, Fábio Joel Kochem; da Veiga, Milton; Doelsch, Emmanuel

2017-03-01

Spreading livestock manure as fertilizer on farmlands is a widespread practice. It represents the major source of heavy metal(loid)s (HM) input in agricultural soils. Since zinc (Zn) is present at high concentrations in manure, it poses special environmental concerns related to phytotoxicity, groundwater contamination, and introduction in the food chain. Therefore, investigations on the fate and behavior of manure-borne Zn, when it enters the soil environment, are necessary to predict the environmental effects. Nevertheless, long-term field studies assessing Zn speciation in the organic waste matrix, as well as within the soil after manure application, are lacking. This study was designed to fill this gap. Using SEM-EDS and XAS analysis, we reported the following new results: (i) ZnS made up 100% of the Zn speciation in the pig slurry (the highest proportion of ZnS ever observed in organic waste); and (ii) ZnS aggregates were about 1-μm diameter (the smallest particle size ever reported in pig slurry). Moreover, the pig slurry containing ZnS was spread on the soil over an 11-year period, totaling 22 applications, and the resulting Zn speciation within the amended soil was analyzed. Surprisingly, ZnS, i.e. the only species responsible for a nearly 2-fold increase in the Zn concentration within the amended soil, was not detected in this soil. Based on SEM-EDS and XAS observations, we put forward the hypothesis that Zn in the pig slurry consisted of nano-sized ZnS crystallites that further aggregated. The low stability of ZnS nanoparticles within oxic and complex environments such as the studied soil was the key explanation for the radical change in pig slurry-borne Zn speciation after long-term amendments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of biochar amendments on microbial transport through soils

USDA-ARS?s Scientific Manuscript database

The incorporation of biochar into soils had been shown to improve soil fertility, enhance soil sequestration of carbon and decrease the mobility of agrochemicals and heavy metals. Our series of column experiments have shown that in addition to these benefits, biochar amendments can limit bacterial t...

Quality of trace element contaminated soils amended with compost under fast growing tree Paulownia fortunei plantation.

PubMed

Madejón, P; Xiong, J; Cabrera, F; Madejón, E

2014-11-01

The use of fast growing trees could be an alternative in trace element contaminated soils to stabilize these elements and improve soil quality. In this study we investigate the effect of Paulownia fortunei growth on trace element contaminated soils amended with two organic composts under semi-field conditions for a period of 18 months. The experiment was carried out in containers filled with tree different soils, two contaminated soils (neutral AZ and acid V) and a non contaminated soil, NC. Three treatments per soil were established: two organic amendments (alperujo compost, AC, and biosolid compost, BC) and a control without amendment addition. We study parameters related with fertility and contamination in soils and plants. Paulownia growth and amendments increased pH in acid soils whereas no effect of these factors was observed in neutral soils. The plant and the amendments also increased organic matter and consequently, soil fertility. Positive results were also found in soils that were only affected by plant growth (without amendment). A general improvement of "soil biochemical quality" was detected over time and treatments, confirming the positive effect of amendments plus paulownia. Even in contaminated soils, except for Cu and Zn, trace element concentrations in leaves were in the normal range for plants. Results of this mid-term study showed that Paulownia fortunei is a promising species for phytoremediation of trace element polluted soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of fresh and aged biochars from pyrolysis and hydrothermal carbonization on nutrient sorption in agricultural soils

NASA Astrophysics Data System (ADS)

Gronwald, M.; Don, A.; Tiemeyer, B.; Helfrich, M.

2015-01-01

Leaching of nutrients from agricultural soils causes major environmental problems that may be reduced with biochar amendments to the soils. Biochars are characterised by a high adsorption capacity, i.e., they may retain nutrients such nitrate and ammonium. However, biochar properties strongly depend on feedstock and the production process. We investigated the nutrient retention capacity of biochars derived from pyrolysis (pyrochar) as well as from hydrothermal carbonization (hydrochar; produced at 200 and 250 °C) from three different feedstocks (digestates, Miscanthus, woodchips) mixed into different soil substrates (sandy loam and silty loam). Moreover, we investigated the influence of biochar degradation on its nutrient retention capacity using a seven-month in-situ field incubation of pyrochar and hydrochar. Pyrochars showed the highest ability to retain nitrate, ammonium and phosphate, with pyrochar from woodchips being particularly efficient in nitrate adsorption. Ammonium adsorption of pyrochars was controlled by the soil type of the soil-biochar mixture. We found some ammonium retention on sandy soils, but no pyrochar effect or even ammonium leaching from the loamy soil. The phosphate retention capacity of pyrochars strongly depended on the pyrochar feedstock with large phosphate leaching from digestate-derived pyrochar and some adsorption capacity from woodchip-derived pyrochar. Application of hydrochars to agricultural soils caused small, and often not significant, effects on nutrient retention. In contrast, some hydrochars did increase the leaching of nutrients compared to the non-amended control soil. We found a surprisingly rapid loss of the biochars' adsorption capacity after field application of the biochars. For all sites and for hydrochar and pyrochar, the adsorption capacity was reduced by 60-80% to less or no nitrate and ammonium adsorption. Thus, our results cast doubt on the efficiency of biochar applications to temperate zone soils to minimize

Effects of fresh and aged chars from pyrolysis and hydrothermal carbonization on nutrient sorption in agricultural soils

NASA Astrophysics Data System (ADS)

Gronwald, M.; Don, A.; Tiemeyer, B.; Helfrich, M.

2015-06-01

Leaching of nutrients from agricultural soils causes major environmental problems that may be reduced with amendments of chars derived from pyrolysis (pyrochars) or hydrothermal carbonization (hydrochars). Chars are characterized by a high adsorption capacity - i.e. they may retain nutrients such as nitrate and ammonium. However, the physicochemical properties of the chars and hence their sorption capacity likely depend on feedstock and the production process. We investigated the nutrient retention capacity of pyrochars and hydrochars from three different feedstocks (digestates, Miscanthus, woodchips) mixed into different soil substrates (sandy loam and silty loam). Moreover, we investigated the influence of char degradation on its nutrient retention capacity using a 7-month in situ field incubation of pyrochar and hydrochar mixed into soils at three different field sites. Pyrochars showed the highest ability to retain nitrate, ammonium and phosphate, with pyrochar from woodchips being particularly efficient in nitrate adsorption. Ammonium adsorption of pyrochars was controlled by the soil type of the soil-char mixture. We found some ammonium retention on sandy soils, but no pyrochar effect or even ammonium leaching from the loamy soil. The phosphate retention capacity of pyrochars strongly depended on the pyrochar feedstock with large phosphate leaching from digestate-derived pyrochar and some adsorption capacity from woodchip-derived pyrochar. Application of hydrochars to agricultural soils caused small, and often not significant, effects on nutrient retention. In contrast, some hydrochars did increase the leaching of nutrients compared to the non-amended control soil. We found a surprisingly rapid loss of the chars' adsorption capacity after field application of the chars. For all sites and for hydrochar and pyrochar, the adsorption capacity was reduced by 60-80 % to less or no nitrate and ammonium adsorption. Thus, our results cast doubt on the efficiency of

National markets for organic waste-derived fertilizers and soil amendments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Logan, T.J.; Pierzynski, G.M.; Pepperman, R.E.

1995-12-31

The last decade has seen enormous growth in the U.S. in the recycling of organic waste materials like sewage sludge, manures, yard waste, solid waste and various industrial wastes. This has been prompted by real or perceived shortages of landfill capacity, state and federal regulations favoring beneficial use of organic wastes, and public support for recycling. Use of fertilizers and soil amendments derived from these wastes has been stimulated by favorable supply-side economics, a shift to organic/sustainable agriculture, and water quality concerns that favor slow-release nutrient sources. This paper summarizes the properties and beneficial use attributes of the various wastesmore » and their derived products, markets for these materials, and constraints/strategies for market penetration.« less

Organic amendments and nutrient leaching in soil columns

USDA-ARS?s Scientific Manuscript database

The lack of nutrient build up in reclaimed coal mine soils would therefore require additional inputs to maintain plant productivity and establishment of a healthy ecosystem. In a greenhouse experiment, reclaimed coal mine soil were amended with fresh and composted poultry manure at the rates based ...

Arsenic in Soils and Forages from Poultry Litter-Amended Pastures

PubMed Central

Ashjaei, Shadi; Miller, William P.; Cabrera, Miguel L.; Hassan, Sayed M.

2011-01-01

In regions of concentrated poultry production, poultry litter (PL) that contains significant quantities of trace elements is commonly surface-applied to pastures at high levels over multiple years. This study examined the effect of long-term applications of PL on soil concentrations of arsenic (As), copper (Cu), Zinc (Zn), and the uptake of these elements by bermuda grass grown on Cecil (well-drained) and Sedgefield (somewhat poorly-drained) soils. The results showed that concentrations of As, Cu, and Zn in soils that had received surface-applied PL over a 14-year period were significantly greater than untreated soil at 0–2.5 and 2.5–7.5 cm depths. However, the levels were well below the USEPA loading limits established for municipal biosolids. Arsenic fractionation showed that concentrations of all As fractions were significantly greater in PL-amended soils compared to untreated soils at 0–2.5 and 2.5–7.5 cm depths. The residual fraction was the predominant form of As in all soils. The water-soluble and NaHCO3-associated As were only 2% of the total As. Significant differences were found in concentrations of these trace elements and phosphorus (P) in forage from PL-amended soils compared to that in untreated plots. The concentrations of Cu, Zn, As, and P were significantly greater in forage from Sedgefield amended soil compared to Cecil soil, but were in all cases below levels of environmental concern. PMID:21655135

Biochar and wood ash amendments for forestry in the Lake States: field report and initial results

Treesearch

Robert P. Richard; Lynette R. Potvin; Evan S. Kane; Stephen D. Handler; Patrick J. Smith; Don Peterson

2017-01-01

Soil amendments are common in agriculture but are not widely used in Lake States forestry. Our objectives were to test the efficacy of operational-scale application of soil amendments on marginal sites as a management strategy for adaptation to drier conditions. Wood ash and biochar amendments were applied throughout 50 acres of recently harvested scrub oak stands, and...

Dissolved organic matter dynamic and resident microbiota evolution in soil amended with fresh and composted olive mill wastes

NASA Astrophysics Data System (ADS)

Gigliotti, Giovanni; Massaccesi, Luisa; Federici, Ermanno; Fidati, Laura; Nasini, Luigi; Proietti, Primo

2013-04-01

The disposal of olive mill wastes represents a problem of environmental relevance particularly in the Mediterranean countries where olive oil is mostly produced. Among the several valorisation and recycling methods proposed, interesting for its operational simplicity and convenience is land spreading, either directly or after composting. However, the agriculture use of the water-saturated husk produced by the new two-phase oil extraction systems may be hampered by its consistency and its high content of phenolic compounds, which may finally lead to phytotoxicity. Humid husk may indeed modify the dynamic of soil organic matter (SOM) and the structure and function of microbial communities. On the other hand, organic amendments are known to positively affect SOM fractions, particularly by increasing the concentration and quality of dissolved organic matter (DOM), which may eventually lead to an increase in microbial activity. The aim of this work was to investigate, during a 90-day field trial, the modifications in soil DOM composition and the effects on the soil microbiota induced by a humid husk, obtained from a new generation two-phase oil extraction plant, spread in an olive orchard either as a fresh amendment or after a composting process. With respect to the control, the soil amended with either fresh or composted husk showed an increase in water extractable organic carbon (WEOC). Interestingly, while during the first 30 days the soil amended with the composted husk showed a WEOC content higher than the one amended with the fresh husk, after that time only in the latter the WEOC remained significantly higher than in the control. The total content of phenolic compounds showed a similar trend, with the only difference that their concentration in the soil amended with both treatments remained higher than the control for the entire trial. Similarly, both treatments induced an increase in soil reducing sugars, with an higher effect observed in the soil amended with

Influence of amendments on soil arsenic fractionation and phytoavailability by Pteris vittata L.

PubMed

Yan, Xiulan; Zhang, Min; Liao, Xiaoyong; Tu, Shuxin

2012-06-01

Increasing availability of soil arsenic is of significance for accelerating phytoremediation efficiency of As-polluted sites. The effects of seven amendments, i.e., citrate, oxalate, EDTA, sodium polyacrylate (SPA), phosphate rock (PR), single superphosphate (SSP), and compost on fractionation and phytoavailability of soil As were investigated in lab culture experiment. The results showed that the addition of PR, SPA, EDTA or compost to soils significantly increased the concentration of NaHCO(3)-extractable As over a 120 d incubation period compared with the control (amendment-free) soil. Then, the four amendments were selected to add to As-contaminated soil growing Pteris vittata. It was concluded that As accumulation by the fern increased significantly under the treatments of PR and SPA by 25% and 31%, respectively. For As fractionation in soil, SPA increased Fe-As significantly by 51% and PR increased Ca-As significantly by 18%, while both the two amendments reduced occluded-As by 16% and 19%, respectively. Adding PR and SPA in soil increased the activities of urease and neutral phosphatase resulting from the improvement the fertility and physical structure of the soil, which benefits plant growth and As absorption of P. vittata. The results of the research revealed that both PR and SPA were effective amendments for improving phytoremediation of As-contaminated sites by P. vittata. Copyright © 2012 Elsevier Ltd. All rights reserved.

Soil biochar amendments: type and dose effects

NASA Astrophysics Data System (ADS)

Ojeda, G.; Domene, X.; Mattana, S.; Sousa, J. P.; Ortiz, O.; Andres, P.; Alcañiz, J. M.

2012-04-01

Biochar is an organic material produced via the pyrolysis of C-based biomass, which is increasingly being recognized by scientists and policy makers for its potential role in carbon sequestration, reducing greenhouse gas emissions, waste mitigation, and as a soil amendment. Recent studies indicated that biochar improves soil fertility through its positive influence on physical-chemical properties, since not only improves water retention, aggregation and permeability, but its high charge density can also hold large amounts of nutrients, increasing crop production. However, it was observed that combustion temperature could affects the degree of aromaticity and the size of aromatic sheets, which in turns determine short-term mineralization rates. To reconcile the different decompasibility observations of biochar, it has sugested that physical protection and interactions with soil minerals play a significant part in biochar stability. In this context, it has initiated one pilot studies which aims to assess the effects of biochar application on physical and chemical properties of agricultural soil under Mediterranean conditions, such as changes in aggregate formation, intra-aggregate carbon sequestration and chemistry of soil water. In the present study, different clases of biochar produced from fast, slow and gasification pyrolisis of vegetal (pine, poplar) and dried sludge biomass, were applied at 1% of biochar-C to mesocosmos of an agricultural soil. Preliminary, it must be pointed out that slow and gasification pyrolisis changes the proportion of particles < 2 mm in diameter, from 10% (original materials) to almost 100%. In contrast, slow pyrolisis not modifies significantly biochar granulometry. As a consequence, bulk density of poplar and pine splinters decreases after fast pyrolisis. Regarding to organic carbon contents of biochar, all biochars obtained from plant biomass presented percentagens of total organic carbon (TOC) between 70 - 90%, while biochar

Carbon and nitrogen mineralization in vineyard acid soils amended with a bentonitic winery waste

NASA Astrophysics Data System (ADS)

Fernández-Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Díaz-Raviña, Montserrat; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel

2015-04-01

Carbon mineralization and nitrogen ammonification processes were determined in different vineyard soils. The measurements were performed in samples non-amended and amended with different bentonitic winery waste concentrations. Carbon mineralization was measured as CO2 released by the soil under laboratory conditions, whereas NH4+ was determined after its extraction with KCl 2M. The time evolution of both, carbon mineralization and nitrogen ammonification, was followed during 42 days. The released CO2 was low in the analyzed vineyard soils, and hence the metabolic activity in these soils was low. The addition of the bentonitic winery waste to the studied soils increased highly the carbon mineralization (2-5 fold), showing that the organic matter added together the bentonitic waste to the soil have low stability. In both cases, amended and non-amended samples, the maximum carbon mineralization was measured during the first days (2-4 days), decreasing as the incubation time increased. The NH4+ results showed an important effect of bentonitic winery waste on the ammonification behavior in the studied soils. In the non-amended samples the ammonification was no detected in none of the soils, whereas in the amended soils important NH4+ concentrations were detected. In these cases, the ammonification was fast, reaching the maximum values of NH4 between 7 and 14 days after the bentonitic waste additions. Also, the percentages of ammonification respect to the total nitrogen in the soil were high, showing that the nitrogen provided by the bentonitic waste to the soil is non-stable. The fast carbon mineralization found in the soils amended with bentonitic winery wastes shows low possibilities of the use of this waste for the increasing the organic carbon pools in the soil.On the other hand, the use of this waste as N-fertilizer can be possible. However, due its fast ammonification, the waste should be added to the soils during active plant growth periods.

Release dynamics of dissolved organic matter in soil amended with biosolids

NASA Astrophysics Data System (ADS)

Trifonov, Pavel; Ilani, Talli; Arye, Gilboa

2014-05-01

Among the soil organic matter (SOM) components, dissolved organic matter (DOM) is the link between the solid phase and the soil solution. Previous studies emphasize the turnover of dissolved organic carbon (DOC) and nitrogen (DON) in soils as major pathways of element cycling. In addition to DOM contribution to carbon, nitrogen and other nutrient budgets, it also influence soil biological activity, reduces metal-ion toxicity, increase the transport of some compounds and contribute to the mineral weathering. Amending soils with biosolids originated from sludge have become very popular in the recent years. Those additions significantly affect the quantity and the composition of the DOM in agricultural soils. It should be noted that under most irrigation habitants, the soil is subjected to drying and re-wetting cycles, inducing a complex changes of soil structure, aggregation, SOM quality and micro-flora. However, most studies that addressed the above issues (directly or indirectly) are engaged with soils under cover of naturally occurring forests of relatively humid areas rather than agricultural soils in arid areas. In the current study we examined the DOC and DON release dynamic of sand and loess soils sampled from the Negev Desert of Israel. Each one of the soils were mixing with 5% (w/w) of one of the biosolids and packed into a Plexiglass column (I.d. 5.2 cm, L=20 cm). The flow-through experiments were conducted under low (1 ml/min) or high (10 ml/min) flow rates in a continuous or interrupted manner. The leachates were collected in time intervals equivalent to about 0.12 pore volume of a given soil-biosolids mixture. The established leaching curves of DOC, DON, NO3-, NH4+ and Cl- are analyzed by water flow and solute transport model for saturate (continuous runs) or variably saturate water flow conditions (interrupted runs). The chemical equilibrium or non-equilibrium (i.e. equilibrium and/or kinetics adsorption/desorption) versions of the convection dispersion

CQESTR Simulation of Soil Organic Matter Dynamics in Long-term Agricultural Experiments across USA

NASA Astrophysics Data System (ADS)

Gollany, H.; Liang, Y.; Albrecht, S.; Rickman, R.; Follett, R.; Wilhelm, W.; Novak, J.

2009-04-01

Soil organic matter (SOM) has important chemical (supplies nutrients, buffers and adsorbs harmful chemical compounds), biological (supports the growth of microorganisms and micro fauna), and physical (improves soil structure and soil tilth, stores water, and reduces surface crusting, water runoff) functions. The loss of 20 to 50% of soil organic carbon (SOC) from USA soils after converting native prairie or forest to production agriculture is well documented. Sustainable management practices for SOC is critical for maintaining soil productivity and responsible utilization of crop residues. As crop residues are targeted for additional uses (e.g., cellulosic ethanol feedstock) developing C models that predict change in SOM over time with change in management becomes increasingly important. CQESTR, pronounced "sequester," is a process-based C balance model that relates organic residue additions, crop management and soil tillage to SOM accretion or loss. The model works on daily time-steps and can perform long-term (100-year) simulations. Soil organic matter change is computed by maintaining a soil C budget for additions, such as crop residue or added amendments like manure, and organic C losses through microbial decomposition. Our objective was to simulate SOM changes in agricultural soils under a range of soil parent materials, climate and management systems using the CQESTR model. Long-term experiments (e.g. Champaign, IL, >100 yrs; Columbia, MO, >100 yrs; Lincoln, NE, 20 yrs) under various tillage practices, organic amendments, crop rotations, and crop residue removal treatments were selected for their documented history of the long-term effects of management practice on SOM dynamics. Simulated and observed values from the sites were significantly related (r2 = 94%, P < 0.001) with slope not significantly different from 1. Recent interest in crop residue removal for biofuel feedstock prompted us to address that as a management issue. CQESTR successfully simulated a

Oxidation of humic substances supports denitrification reactions in agricultural soils.

NASA Astrophysics Data System (ADS)

van Trump, J. I.; Coates, J. D.

2007-12-01

Humic substances (HS) are a ubiquitous, recalcitrant, and diverse class of compounds arising from degradation and condensation of plant and microbial biopolymers. Many bacteria oxidize hydroquinones within humic substances to their quinone analogs, providing electrons for respiratory processes such as nitrate reduction. Microbial hydroquinone oxidation contributes to the redox state of HS and supports denitrification, which may be of import to agricultural soils where nitrate retention is critical and HS are prevalent. Most probable number counts were performed on soils collected from a Nebraska farm, with the model humic hydroquinone 2,6- anthrahydroquinone disulfonate (AHDS) serving as an electron donor and nitrate as the electron acceptor. Results indicated that AHDS oxidizing, nitrate reducing bacteria were present in soils from bluegrass fields (104 cells/g) and aspen groves (106 cells/g), as well as in plots of corn (106 cells/g), and soybean treated (106 cells/g) and un-treated (105 cells/g) with pig slurry. These results demonstrate that microorganisms participating in the proposed metabolism are prevalent within agricultural soils. Upflow glass columns were constructed, containing a support matrix of glass beads amended with 10% w/w soil from the corn plot previously mentioned. All columns were subjected to a continual flow of phosphate-buffered water amended with sodium nitrate. Above the point source for nitrate injection, phosphate-buffered water containing electron donor treatments were continually injected. The impacts of electron donor treatments (no donor, oxidized HS, reduced HS, and acetate) on denitrification and other geochemical parameters were observed. Column studies were able to resolve effects of electron donor treatment both spatially as a function of distance from the injection point source, and temporally, as a function of time of donor treatment. Four sample ports in each column were routinely analyzed for concentrations of nitrate

Immobilization of tetracyclines in manure and manure-amended soils using aluminum-based drinking water treatment residuals.

PubMed

Punamiya, Pravin; Sarkar, Dibyendu; Rakshit, Sudipta; Elzinga, Evert J; Datta, Rupali

2016-02-01

Veterinary antibiotics (VAs) are emerging contaminants of concern in the environment, mainly due to the potential for development of antibiotic-resistant bacteria and effect on microbiota that could interfere with crucial ecosystem functions such as nutrient cycling and decomposition. High levels of VAs such as tetracyclines (TCs) have been reported in agricultural soils amended with manure, which also has the potential to cause surface and groundwater contamination. Several recent studies have focused on developing methods to immobilize VAs such as composting with straw, hardwood chips, commercial biochar, aeration, mixing, heat treatment, etc. The major shortcomings of these methods include high cost and limited effectiveness. In the current study, we assessed the effectiveness of aluminum-based drinking water treatment residuals (Al-WTR) as a "green" sorbent to immobilize TCs in manure and manure-applied soils with varying physicochemical properties by laboratory incubation study. Results show that Al-WTR is very effective in immobilizing tetracycline (TTC) and oxytetracycline (OTC). The presence of phosphate resulted in significant (p < 0.01) decrease in TTC/OTC sorption by Al-WTR, but the presence of sulfate did not. attenuated total reflection (ATR)-FTIR spectroscopy indicate that TTC and OTC likely forming surface complexes via inner-sphere-type bonds in soils, manure, and manure-applied soils amended with Al-WTR.

Soil moisture: Some fundamentals. [agriculture - soil mechanics

NASA Technical Reports Server (NTRS)

Milstead, B. W.

1975-01-01

A brief tutorial on soil moisture, as it applies to agriculture, is presented. Information was taken from books and papers considered freshman college level material, and is an attempt to briefly present the basic concept of soil moisture and a minimal understanding of how water interacts with soil.

Summer cover crops and soil amendments to improve growth and nutrient uptake of okra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Q.R.; Li, Y.C.; Klassen, W.

2006-04-15

A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (amore » combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.« less

Amending soils with phosphate as means to mitigate soil lead hazard: a critical review of the state of the science.

PubMed

Scheckel, Kirk G; Diamond, Gary L; Burgess, Michele F; Klotzbach, Julie M; Maddaloni, Mark; Miller, Bradley W; Partridge, Charles R; Serda, Sophia M

2013-01-01

Ingested soil and surface dust may be important contributors to elevated blood lead (Pb) levels in children exposed to Pb contaminated environments. Mitigation strategies have typically focused on excavation and removal of the contaminated soil. However, this is not always feasible for addressing widely disseminated contamination in populated areas often encountered in urban environments. The rationale for amending soils with phosphate is that phosphate will promote formation of highly insoluble Pb species (e.g., pyromorphite minerals) in soil, which will remain insoluble after ingestion and, therefore, inaccessible to absorption mechanisms in the gastrointestinal tract (GIT). Amending soil with phosphate might potentially be used in combination with other methods that reduce contact with or migration of contaminated soils, such as covering the soil with a green cap such as sod, clean soil with mulch, raised garden beds, or gravel. These remediation strategies may be less expensive and far less disruptive than excavation and removal of soil. This review evaluates evidence for efficacy of phosphate amendments for decreasing soil Pb bioavailability. Evidence is reviewed for (1) physical and chemical interactions of Pb and phosphate that would be expected to influence bioavailability, (2) effects of phosphate amendments on soil Pb bioaccessibility (i.e., predicted solubility of Pb in the GIT), and (3) results of bioavailability bioassays of amended soils conducted in humans and animal models. Practical implementation issues, such as criteria and methods for evaluating efficacy, and potential effects of phosphate on mobility and bioavailability of co-contaminants in soil are also discussed.

Cu retention in an acid soil amended with perlite winery waste.

PubMed

Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Calviño, David

2016-02-01

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.

Evaluation of different amendments to stabilize antimony in mining polluted soils.

PubMed

Álvarez-Ayuso, E; Otones, V; Murciego, A; García-Sánchez, A

2013-02-01

Soil pollution with antimony is of increasing environmental concern worldwide. Measures for its control and to attenuate the risks posed to the ecosystem are required. In this study the application of several iron and aluminium oxides and oxyhydroxides as soil amendments was evaluated in order to assess their feasibility to stabilize Sb in mining polluted soils. Mine soils with different pollution levels were amended with either goethite, ferrihydrite or amorphous Al oxide at various ratios (0-10%). The effectiveness of such treatments was assessed by both batch and column leaching tests. The use of ferrihydrite or amorphous Al oxide proved to be highly effective to stabilize Sb. Immobilization levels of 100% were found when doses of 5% ferrihydrite or 10% amorphous Al oxide were applied, regardless of the soil Sb load. Column leaching studies also showed a high Sb leaching reduction (>75%) when soils were amended with 1% ferrihydrite or 5% amorphous Al oxide. Moreover, such treatments proved to simultaneously immobilize As and Pb in a great extent when soils were also polluted with such toxic elements. Copyright © 2012 Elsevier Ltd. All rights reserved.

Immobilizer-assisted management of metal-contaminated agricultural soils for safer food production.

PubMed

Kim, Kwon-Rae; Kim, Jeong-Gyu; Park, Jeong-Sik; Kim, Min-Suk; Owens, Gary; Youn, Gyu-Hoon; Lee, Jin-Su

2012-07-15

Production of food crops on metal contaminated agricultural soils is of concern because consumers are potentially exposed to hazardous metals via dietary intake of such crops or crop derived products. Therefore, the current study was conducted to develop management protocols for crop cultivation to allow safer food production. Metal uptake, as influenced by pH change-induced immobilizing agents (dolomite, steel slag, and agricultural lime) and sorption agents (zeolite and compost), was monitored in three common plants representative of leafy (Chinese cabbage), root (spring onion) and fruit (red pepper) vegetables, in a field experiment. The efficiency of the immobilizing agents was assessed by their ability to decrease the phytoavailability of metals (Cd, Pb, and Zn). The fruit vegetable (red pepper) showed the least accumulation of Cd (0.16-0.29 mgkg(-1) DW) and Pb (0.2-0.9 mgkg(-1) DW) in edible parts regardless of treatment, indicating selection of low metal accumulating crops was a reasonable strategy for safer food production. However, safer food production was more likely to be achievable by combining crop selection with immobilizing agent amendment of soils. Among the immobilizing agents, pH change-induced immobilizers were more effective than sorption agents, showing decreases in Cd and Pb concentrations in each plant well below standard limits. The efficiency of pH change-induced immobilizers was also comparable to reductions obtained by 'clean soil cover' where the total metal concentrations of the plow layer was reduced via capping the surface with uncontaminated soil, implying that pH change-induced immobilizers can be practically applied to metal contaminated agricultural soils for safer food production. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of charcoal amendment on adsorption, leaching and degradation of isoproturon in soils

NASA Astrophysics Data System (ADS)

Si, Youbin; Wang, Midao; Tian, Chao; Zhou, Jing; Zhou, Dongmei

2011-04-01

The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r = 0.957 **, P < 0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation ( DT50) in soils greatly extended when the rate of added charcoal inceased from 0 to 50 g kg - 1 (for Paddy soil, DT50 values increased from 54.6 to 71.4 days; for Alfisol, DT50 from 16.0 to 136 days; and for Vertisol, DT50 from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils.

Effect of charcoal amendment on adsorption, leaching and degradation of isoproturon in soils.

PubMed

Si, Youbin; Wang, Midao; Tian, Chao; Zhou, Jing; Zhou, Dongmei

2011-04-01

The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r=0.957**, P<0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation (DT(50)) in soils greatly extended when the rate of added charcoal increased from 0 to 50 g kg(-1) (for Paddy soil, DT(50) values increased from 54.6 to 71.4 days; for Alfisol, DT(50) from 16.0 to 136 days; and for Vertisol, DT(50) from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils. Copyright © 2010 Elsevier B.V. All rights reserved.

Improving Phosphorus Availability in an Acid Soil Using Organic Amendments Produced from Agroindustrial Wastes

PubMed Central

Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab.

2014-01-01

In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments. PMID:25032229

A multi-site, multi-year examination of factors affecting the persistence of attenuated O157- and non-pathogenic Escherichia coli in manure-amended soils in the mid-Atlantic United States

USDA-ARS?s Scientific Manuscript database

The addition of untreated biological soil amendments (BSAs), including dairy cattle manure (DM), poultry litter (PL), and horse manure (HM), to soils provides nutrients for crops in conventional and organic agriculture, but may also introduce enteric pathogens present in manure to crops. The U.S. Fo...

Characterization of a soil amendment derived from co-composting of agricultural wastes and biochar

NASA Astrophysics Data System (ADS)

Curaqueo, Gustavo; Ángel Sánchez-Monedero, Miguel; Meier, Sebastián; Medina, Jorge; Panichini, Marcelo; Borie, Fernando; Navia, Rodrigo

2016-04-01

contents increased in BC10 treatment, while the K contents were similar in all treatments as well as C/N ratio (around 15). The organic matter content was BC10>BC5>BC0 and the dissolved organic C content was lower than 8.3 g kg-1 for all piles confirming the maturity of compost. The germination test showed a non-toxic effect of all amendments in the species assayed obtaining a germination index between 55% and 80.7% indicating maturity of the amendments evaluated. Our results indicated that the combined use of agricultural wastes and biochar by mean of a co-composting process is a suitable option for generating good quality amendments for improving soil condition and optimizing nutrient cycling at farm scale. Financial support for this research was provided by the National Commission for Scientific and Technological Research through FONDECYT 11140508 Project

Assessment of tomato and wine processing solid wastes as soil amendments for biosolarization.

PubMed

Achmon, Yigal; Harrold, Duff R; Claypool, Joshua T; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

2016-02-01

Pomaces from tomato paste and wine production are the most abundant fruit processing residues in California. These residues were examined as soil amendments for solarization to promote conditions conducive to soil disinfestation (biosolarization). Simulated biosolarization studies were performed in both aerobic and anaerobic soil environments and soil temperature elevation, pH, and evolution of CO2, H2 and CH4 gases were measured as metrics of soil microbial activity. Tomato pomace amendment induced conditions associated with soil pest inactivation, including elevation of soil temperature by up to 2°C for a duration of 4days under aerobic conditions and a reduction of soil pH from 6.5 to 4.68 under anaerobic conditions. White wine grape pomace amendment showed similar trends but to a lesser extent. Red wine grape pomace was generally less suitable for biosolarization due to significantly lower soil temperature elevations, reduced acidification relative to the other pomaces and induction of methanogenesis in the soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anaerobic soil disinfestation and Brassica seed meal amendment alter soil microbiology and system resistance

USDA-ARS?s Scientific Manuscript database

Brassica seed meal amendments and anaerobic soil disinfestation control a spectrum of soil-borne plant pathogens via a diversity of mechanisms. Transformations in microbial community structure and function in certain instances were determinants of disease control and enhanced plant performance. Fo...

Biochar amendment immobilizes lead in rice paddy soils and reduces its phytoavailability

PubMed Central

Li, Honghong; Liu, Yuting; Chen, Yanhui; Wang, Shanli; Wang, Mingkuang; Xie, Tuanhui; Wang, Guo

2016-01-01

This study aimed to determine effects of rice straw biochar on Pb sequestration in a soil-rice system. Pot experiments were conducted with rice plants in Pb-contaminated paddy soils that had been amended with 0, 2.5, and 5% (w/w) biochar. Compared to the control treatment, amendment with 5% biochar resulted in 54 and 94% decreases in the acid soluble and CaCl2-extractable Pb, respectively, in soils containing rice plants at the maturity stage. The amount of Fe-plaque on root surfaces and the Pb concentrations of the Fe-plaque were also reduced in biochar amended soils. Furthermore, lead species in rice roots were determined using Pb L3-edge X-ray absorption near edge structure (XANES), and although Pb-ferrihydrite complexes dominated Pb inventories, increasing amounts of organic complexes like Pb-pectins and Pb-cysteine were found in roots from the 5% biochar treatments. Such organic complexes might impede Pb translocation from root to shoot and subsequently reduce Pb accumulation in rice with biochar amendment. PMID:27530495

Biochar amendment immobilizes lead in rice paddy soils and reduces its phytoavailability

NASA Astrophysics Data System (ADS)

Li, Honghong; Liu, Yuting; Chen, Yanhui; Wang, Shanli; Wang, Mingkuang; Xie, Tuanhui; Wang, Guo

2016-08-01

This study aimed to determine effects of rice straw biochar on Pb sequestration in a soil-rice system. Pot experiments were conducted with rice plants in Pb-contaminated paddy soils that had been amended with 0, 2.5, and 5% (w/w) biochar. Compared to the control treatment, amendment with 5% biochar resulted in 54 and 94% decreases in the acid soluble and CaCl2-extractable Pb, respectively, in soils containing rice plants at the maturity stage. The amount of Fe-plaque on root surfaces and the Pb concentrations of the Fe-plaque were also reduced in biochar amended soils. Furthermore, lead species in rice roots were determined using Pb L3-edge X-ray absorption near edge structure (XANES), and although Pb-ferrihydrite complexes dominated Pb inventories, increasing amounts of organic complexes like Pb-pectins and Pb-cysteine were found in roots from the 5% biochar treatments. Such organic complexes might impede Pb translocation from root to shoot and subsequently reduce Pb accumulation in rice with biochar amendment.

Structure, composition and metagenomic profile of soil microbiomes associated to agricultural land use and tillage systems in Argentine Pampas.

PubMed

Carbonetto, Belén; Rascovan, Nicolás; Álvarez, Roberto; Mentaberry, Alejandro; Vázquez, Martin P

2014-01-01

Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no-tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems may

Structure, Composition and Metagenomic Profile of Soil Microbiomes Associated to Agricultural Land Use and Tillage Systems in Argentine Pampas

PubMed Central

Carbonetto, Belén; Rascovan, Nicolás; Álvarez, Roberto; Mentaberry, Alejandro; Vázquez, Martin P.

2014-01-01

Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no- tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems

Removal of Chromium from Soils Cultivated with Maize (Zea Mays) After the Addition of Natural Minerals as Soil Amendments.

PubMed

Μolla, A; Ioannou, Z; Mollas, S; Skoufogianni, E; Dimirkou, A

2017-03-01

The efficiency of natural minerals, i.e. zeolite, bentonite and goethite, regarding the retention of chromium, from maize was examined. Specifically, 1.0 kg of soil, 1.0 g of soil amendment and either 50 mg L -1 Cr(III) or 1 mg L -1 Cr(VI) were added in plant pots. Then, seeds of maize were cultivated. Each treatment was repeated three times. The statistical results of the experiments were analyzed by LSD test. Cr(III) addition in soil has shown that zeolite was the only amendment that increased the dry weight. Zeolite and bentonite reduced significantly the total chromium in plants after the addition of 50 mg L -1 Cr(III). The addition of Cr(VI) in soil has shown that bentonite was the only amendment that increased the dry weight of biomass and the plants' height. All soil amendments reduced to zero the total chromium concentration measured to plants after the addition of 1 mg L -1 Cr(VI).

Effects of soil dilution and amendments (mussel shell, cow bone, and biochar) on Pb availability and phytotoxicity in military shooting range soil.

PubMed

Ahmad, Mahtab; Soo Lee, Sang; Yang, Jae E; Ro, Hee-Myong; Han Lee, Young; Sik Ok, Yong

2012-05-01

Bioavailability and bioaccessibility determine the level of metal toxicity in the soils. Inorganic soil amendments may decrease metal bioavailability and enhance soil quality. This study used mussel shell, cow bone, and biochar to reduce lead (Pb) toxicity in the highly contaminated military shooting range soil in Korea. Water-soluble and 1-M ammonium nitrate extractions, and a modified physiologically based extraction test (PBET) were performed to determine Pb bioavailability and bioaccessibility in the soil, respectively. Active C in the soil was also measured to evaluate the effects of the amendments on biological soil quality. The Pb contaminated soil was diluted in serial with uncontaminated soil for the bioassays. Seed germination and root elongation tests using lettuce (Lactuca sativa) showed increases in germination percentage and root length in soil treated with the amendments. Biochar was most effective and increased seed germination by 360% and root length by 189% compared to the unamended soil. Up to 20% soil dilution resulted in more than 50% seed germination. Bioavailability and bioaccessibility of Pb in the soils were decreased by 92.5% and 48.5% with mussel shell, by 84.8% and 34.5% with cow bone, and by 75.8% and 12.5% with biochar, respectively, compared to the unamended soil. We found that the Pb availability in the military shooting range soil can be reduced effectively by the tested amendments or soil dilution alternately, thereby decreasing the risk of ecotoxicity. Furthermore, the increasing active C from the amendments revitalized the soil contaminated with Pb. Copyright © 2012 Elsevier Inc. All rights reserved.

The EDTA Amendment in Phytoextraction of (134)Cs From Soil by Indian Mustard (Brassica juncea).

PubMed

Tjahaja, Poppy Intan; Sukmabuana, Putu; Roosmini, Dwina

2015-01-01

Soil contamination with radiocaesium is a significant problem at any countries when a nuclear accident occurred. Recently, phytoextraction technique is developed to remediate the contaminated environment. However, the application is limited by the availability of the contaminant for root uptake. Therefore, a green house trial experiment of soil amendment with ethylene diamine tetraacetic acid (EDTA) has been conducted to examine (134)Cs availability for root uptake. Two groups of Indian mustard (Brassica juncea) were cultivated in (134)Cs contaminated soil. The soil in the first group was treated with EDTA amendment, while the other was not. Plant growth was observed gravimetrically and the (134)Cs concentration in soil as well as plants were determined using gamma spectrometry. The plant uptake capacity was determined as transfer factor (Fv), and the Fv values of 0.22 ± 0.0786 and 0.12 ± 0.039 were obtained for the soil treated with and without EDTA amendment, respectively. The phytoextraction efficiency of the plant cultivated in (134)Cs contaminated soil both with and without EDTA amendment was low. The EDTA amendment to the soil seems to enhance the (134)Cs availability for root uptake of Indian mustard and can still be considered to assist the field phytoremediation of contaminated soil.

Effects of Biochar amendments on soil chemistry

NASA Astrophysics Data System (ADS)

Mukherjee, A.; Zimmerman, A. R.

2009-12-01

Humans have been transforming soil composition, both accidentally and purposefully, for centuries. For example, terra preta soils found in Amazonia that are greatly enriched in organic carbon and phosphorus and have enhanced fertility relative to the surrounding depleted oxisols, seem to have been deliberately created by native pre-Colombian Indians through the addition of combusted biomass, or biochar. Biochar amendment has gained attention recently as a way to enhance soil carbon sequestration while increasing soil fertility. It may also have adsorptive properties that are useful for pollution control. Our research examines the chemical and morphological properties of biochar with the goals of understanding the origin of terra preta, as well as how biochar can best be put to use as a soil amendment. Biochar was produced from a range of parent biomass types (hardwoods, softwoods and grasses) and under a range of combustion conditions (250 to 650 oC, under air and N2). Surface areas, determined by gas sorptometry, ranged from 3 to 394 m2g-1 (for N2) and from 129 to 345 m2g-1 (for CO2) and were found to generally increase with increasing pyrolysis temperature. The pH of the biochars ranged from 1.8 to 4.5, from 6.2 to 8.7, and from 6.2 to 9.2 for the 250, 400, and 650 oC biochars, respectively, and did not vary consistently with parent biomass types. Cation exchange capacity (CEC), determined using K+ exchange, ranged between 5 to 60 cmolc kg-1, higher than most soils, and generally increased with charring temperature. Anion exchange capacity (AEC) was low or undetectable. Lastly, the isoelectric point of the chars, determined using a zeta potential analyzer, ranged from a pH of 1.3 to 1.5, indicating that the biochar surfaces will be predominantly negatively charged in soil solutions. These data are complimentary and show that, when added to soil, biochar, particularly those produced at higher temperatures, would function as a cation exchanger system. The acid

Role of organic amendments on enhanced bioremediation of heavy metal(loid) contaminated soils.

PubMed

Park, Jin Hee; Lamb, Dane; Paneerselvam, Periyasamy; Choppala, Girish; Bolan, Nanthi; Chung, Jae-Woo

2011-01-30

As land application becomes one of the important waste utilization and disposal practices, soil is increasingly being seen as a major source of metal(loid)s reaching food chain, mainly through plant uptake and animal transfer. With greater public awareness of the implications of contaminated soils on human and animal health there has been increasing interest in developing technologies to remediate contaminated sites. Bioremediation is a natural process which relies on soil microorganisms and higher plants to alter metal(loid) bioavailability and can be enhanced by addition of organic amendments to soils. Large quantities of organic amendments, such as manure compost, biosolid and municipal solid wastes are used as a source of nutrients and also as a conditioner to improve the physical properties and fertility of soils. These organic amendments that are low in metal(loid)s can be used as a sink for reducing the bioavailability of metal(loid)s in contaminated soils and sediments through their effect on the adsorption, complexation, reduction and volatilization of metal(loid)s. This review examines the mechanisms for the enhanced bioremediation of metal(loid)s by organic amendments and discusses the practical implications in relation to sequestration and bioavailability of metal(loid)s in soils. Copyright © 2010 Elsevier B.V. All rights reserved.

Major element, trace element, nutrient, and radionuclide mobility in a mining by-product-amended soil.

PubMed

Douglas, G; Adeney, J; Johnston, K; Wendling, L; Coleman, S

2012-01-01

This study investigates the use of a mineral processing by-product, neutralized used acid (NUA), primarily composed of gypsum and Fe-oxyhydroxide, as a soil amendment. A 1489-d turf farm field trial assessed nutrient, trace element, and radionuclide mobility of a soil amended with ∼5% by mass to a depth of 15 cm of NUA. Average PO-P fluxes collected as subsoil leachates were 0.7 and 26.6 kg ha yr for NUA-amended and control sites, respectively, equating to a 97% reduction in PO-P loss after 434 kg P ha was applied. Total nitrogen fluxes in NUA-amended soil leachates were similarly reduced by 82%. Incorporation of NUA conferred major changes in leachate geochemistry with a diverse suite of trace elements depleted within NUA-amended leachates. Gypsum dissolution from NUA resulted in an increase from under- to oversaturation of the soil leachates for a range of Fe- and Ca-minerals including calcite and ferrihydrite, many of which have a well-documented ability to assimilate PO-P and trace elements. Isotopic analysis indicated little Pb addition from NUA. Both Sr and Nd isotope results revealed that NUA and added fertilizer became an important source of Ca to leachate and turf biomass. The NUA-amended soils retained a range of U-Th series radionuclides, with little evidence of transfer to soil leachate or turf biomass. Calculated radioactivity dose rates indicate only a small increment due to NUA amendment. With increased nutrient, trace element, and solute retention, and increased productivity, a range of potential agronomic benefits may be conferred by NUA amendment of soils, in addition to the potential to limit offsite nutrient loss and eutrophication. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Surfactant-Modified Soil Amendments Reduce Nitrogen and Phosphorus Leaching in a Sand-Based Rootzone.

PubMed

Shaddox, Travis W; Kruse, Jason K; Miller, Grady L; Nkedi-Kizza, Peter; Sartain, Jerry B

2016-09-01

United States Golf Association putting greens are susceptible to nitrogen (N) and phosphorus (P) leaching. Inorganic soil amendments are used to increase moisture and nutrient retention and may influence N and P leaching. This study was conducted to determine whether N and P leaching could be reduced using soil amendments and surfactant-modified soil amendments. Treatments included a control (sand), sand-peat, zeolite, calcined clay, hexadecyltrimethylammonium-zeolite, and hexadecyltrimethylammonium-calcined clay. Lysimeters were filled with a 30-cm rootzone layer of sand-peat (85:15 by volume), below which a 5-cm treatment layer of amendments was placed. A solution of NO-N, NH-N, and orthophosphate-P (2300, 2480, and 4400 μg mL, respectively) was injected at the top of each lysimeter, and leachate was collected using an autocollector set to collect a 10-mL sample every min until four pore volumes were collected. Uncoated amendments, sand, and peat had no influence on NO-N retention, whereas hexadecyltrimethylammonium-coated amendments reduced NO-N leaching to below detectable limits. Both coated and uncoated amendments reduced NH-N leaching, with zeolite reducing NH-N leached to near zero regardless of hexadecyltrimethylammonium coating. Pure sand resulted in a 13% reduction of applied orthophosphate-P leaching, whereas peat contributed to orthophosphate-P leaching. Surfactant-modified amendments reduced orthophosphate-P leaching by as much as 97%. Surfactant-modified soil amendments can reduce NO-N, NH-N, and orthophosphate-P leaching and, thus, may be a viable option for removing leached N and P before they enter surface or ground waters. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Persistence of Escherichia coli in manure-amended soil in Pennsylvania

USDA-ARS?s Scientific Manuscript database

Potential for pathogen transfer from soils amended with untreated animal manure to crops and the frequent occurrence of foodborne illness outbreaks involving Escherichia coli O157:H7 prompted the FDA proposal requiring a 9-month waiting period before harvesting produce from manure-amended fields. A...

Maize (Zea mays L.) performance in organically amended mine site soils.

PubMed

Oladipo, Oluwatosin Gbemisola; Olayinka, Akinyemi; Awotoye, Olusegun Olufemi

2016-10-01

Organic amendments play an important role in the eco-friendly remediation of degraded mine site soils. This study investigated the quality (essential nutrients and heavy metal content) of maize grown on organically amended soils from three active mines in Nigeria. Soil samples were collected randomly at 0-15 cm depth, air-dried and sieved. Five kg of soil were amended with poultry manure and sawdust (poultry manure only, sawdust only, poultry manure-sawdust mixtures in 3:1, 2:1 and 1:1 ratios) at 10 g kg(-1). Maize (Zea mays L.) seeds were planted and watered for two consecutive periods of 8 weeks, with the control and treatment experiments set up in the screenhouse in quadruples. Harvested tissues were weighed, dried, ground and digested. Chemical properties were determined using standard methods while atomic absorption spectrophotometry was used to determine total metal concentrations (Ca, Mg, Fe, Zn, Pb, Cd and Cu). ANOVA was used to test for significant differences among treatment groups in the various parameters. Application of poultry manure-sawdust mixtures significantly (p < 0.05) enhanced tissue dry matter yield, as well as N, P, K, and Na contents while Zn, Cd, Cu and Pb were immobilized to approximately 50-100%. Treatment with sawdust alone reduced tissue nutrient content resulting in depressed plant yield while poultry manure only though enhanced crop yield, contained higher heavy metal contents. Soil amendments comprised of poultry manure-sawdust mixtures can be effective remediation strategy for mine site soils, as these organic materials help replenish soil nutrients, immobilize heavy metals, and enhance food productivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Utilization of FGD gypsum in agriculture for environmental benefits

USDA-ARS?s Scientific Manuscript database

This paper will discuss the utilization of FGD gypsum in agriculture for environmental benefits. Gypsum (CaSO4 .2H2O) has been used as an agricultural soil amendment for over 250 years. It is a soluble source of calcium and sulfur for crops and has been shown to improve soil physical and chemical pr...

Humic Substances in Organic Wastes and their Effects on Amended Soils

NASA Astrophysics Data System (ADS)

Senesi, N.; Ciavatta, C.; Plaza, C.

2009-04-01

Soil humic substances (HS) are universally recognized to play a major role in a wide number of agronomic and environmental processes. For example, soil HS are able to bind mineral particles together, thus promoting a good soil structure, constitute an important source of nutrients for plants and microorganisms, contribute largely to the acid-base buffering capacity of soils, and exert a marked control on the biological availability, physico-chemical behavior, and environmental fate of toxic metal ions and xenobiotics. For these reasons, the knowledge of the short- and long-term effects of organic amendments on the status, quality, and reactivity of indigenous soil HS is of paramount importance. The objective of this presentation is to provide an overview of the chemical and physico-chemical data available in the literature for the evaluation of the effects of organic wastes of various origin and nature used as soil amendments on the composition, structure, and chemical reactivity of native soil HS. In general, HS-like components of organic wastes are typically characterized by a relatively larger presence of aliphatic, amide, and polysaccharide structures, simple structural components of wide molecular heterogeneity, smaller contents of oxygen, acidic functional groups, and organic free radicals, and smaller degrees of aromatic ring polycondensation, polymerization, and humification than native soil HS. Further, with respect to native soil HS, HS-like fractions from organic wastes generally exhibit smaller binding capacities and affinities for metal ions and organic xenobiotics. Appropriate treatment processes of raw organic wastes able to produce environmentally safe and agronomically efficient soil amendments, such as composting, yield HS-like fractions characterized by chemical and physico-chemical features that approach those of native soil HS. In general, aliphatic, polysaccharide, and lignin structures and S- and N-containing groups of the HS-like fractions

ECO-FRIENDLY ADDITIVES FOR BIODEGRADATION OF AGRICULTURAL MULCHES

EPA Science Inventory

The main output is a new method to facilitate microbial assimilation of “biodegradable” agricultural mulches through addition of amendment(s) to the mulches at the end of their service life, prior to their being plowed into the soil.  The outcome is the identifi...

Activated carbon amendment to sequester PAHs in contaminated soil: a lysimeter field trial.

PubMed

Hale, Sarah E; Elmquist, Marie; Brändli, Rahel; Hartnik, Thomas; Jakob, Lena; Henriksen, Thomas; Werner, David; Cornelissen, Gerard

2012-04-01

Activated carbon (AC) amendment is an innovative method for the in situ remediation of contaminated soils. A field-scale AC amendment of either 2% powder or granular AC (PAC and GAC) to a PAH contaminated soil was carried out in Norway. The PAH concentration in drainage water from the field plot was measured with a direct solvent extraction and by deploying polyoxymethylene (POM) passive samplers. In addition, POM samplers were dug directly in the AC amended and unamended soil in order to monitor the reduction in free aqueous PAH concentrations in the soil pore water. The total PAH concentration in the drainage water, measured by direct solvent extraction of the water, was reduced by 14% for the PAC amendment and by 59% for GAC, 12 months after amendment. Measurements carried out with POM showed a reduction of 93% for PAC and 56% for GAC. The free aqueous PAH concentration in soil pore water was reduced 93% and 76%, 17 and 28 months after PAC amendment, compared to 84% and 69% for GAC. PAC, in contrast to GAC, was more effective for reducing freely dissolved concentrations than total dissolved ones. This could tentatively be explained by leaching of microscopic AC particles from PAC. Secondary chemical effects of the AC amendment were monitored by considering concentration changes in dissolved organic carbon (DOC) and nutrients. DOC was bound by AC, while the concentrations of nutrients (NO(3), NO(2), NH(4), PO(4), P-total, K, Ca and Mg) were variable and likely affected by external environmental factors. Copyright © 2012 Elsevier Ltd. All rights reserved.

Plant absorption of trace elements in sludge amended soils and correlation with soil chemical speciation.

PubMed

Torri, Silvana; Lavado, Raúl

2009-07-30

The aim of the present study was to investigate the relationship between Lolium perenne L. uptake of Cd, Cu, Pb, and Zn in sludge amended soils and soil availability of these elements assessed by soil sequential extraction. A greenhouse experiment was set with three representative soils of the Pampas Region, Argentina, amended with sewage sludge and sewage sludge enriched with its own incinerated ash. After the stabilization period of 60 days, half of the pots were sampled for soil analysis; the rest of the pots were sown with L. perenne and harvested 8, 12, 16 and 20 weeks after sowing, by cutting just above the soil surface. Cadmium and Pb concentrations in aerial tissues of L. perenne were below detection limits, in good agreement with the soil fractionation study. Copper and Zn concentration in the first harvest were significantly higher in the coarse textured soil compared to the fine textured soil, in contrast with soil chemical speciation. In the third harvest, there was a positive correlation between Cu and Zn concentration in aerial biomass and soil fractions usually considered of low availability. We conclude that the most available fractions obtained by soil sequential extraction did not provide the best indicator of Cu and Zn availability to L. perenne.

Use of mixed solid waste as a soil amendment for saline-sodic soil remediation and oat seedling growth improvement.

PubMed

Fan, Yuan; Ge, Tian; Zheng, Yanli; Li, Hua; Cheng, Fangqin

2016-11-01

Soil salinization has become a worldwide problem that imposes restrictions on crop production and food quality. This study utilizes a soil column experiment to address the potential of using mixed solid waste (vinegar residue, fly ash, and sewage sludge) as soil amendment to ameliorate saline-sodic soil and enhance crop growth. Mixed solid waste with vinegar residue content ranging from 60-90 %, sewage sludge of 8.7-30 %, and fly ash of 1.3-10 % was added to saline-sodic soil (electrical conductivity (EC 1:5 ) = 1.83 dS m -1 , sodium adsorption ratio (SAR 1:5 ) = 129.3 (mmol c L -1 ) 1/2 , pH = 9.73) at rates of 0 (control), 130, 260, and 650 kg ha -1 . Results showed that the application of waste amendment significantly reduced SAR, while increasing soil soluble K + , Ca 2+ , and Mg 2+ , at a dose of 650 kg ha -1 . The wet stability of macro-aggregates (>1 mm) was improved 90.7-133.7 % when the application rate of amendment was greater than 260 kg ha -1 . The application of this amendment significantly reduced soil pH. Germination rates and plant heights of oats were improved with the increasing rate of application. There was a positive correlation between the percentage of vinegar residue and the K/Na ratio in the soil solutions and roots. These findings suggest that applying a mixed waste amendment (vinegar residue, fly ash, and sewage sludge) could be a cost-effective method for the reclamation of saline-sodic soil and the improvement of the growth of salt-tolerant plants.

Combined Flux Chamber and Genomics Approach Links Nitrous Acid Emissions to Ammonia Oxidizing Bacteria and Archaea in Urban and Agricultural Soil.

PubMed

Scharko, Nicole K; Schütte, Ursel M E; Berke, Andrew E; Banina, Lauren; Peel, Hannah R; Donaldson, Melissa A; Hemmerich, Chris; White, Jeffrey R; Raff, Jonathan D

2015-12-01

Nitrous acid (HONO) is a photochemical source of hydroxyl radical and nitric oxide in the atmosphere that stems from abiotic and biogenic processes, including the activity of ammonia-oxidizing soil microbes. HONO fluxes were measured from agricultural and urban soil in mesocosm studies aimed at characterizing biogenic sources and linking them to indigenous microbial consortia. Fluxes of HONO from agricultural and urban soil were suppressed by addition of a nitrification inhibitor and enhanced by amendment with ammonium (NH4(+)), with peaks at 19 and 8 ng m(-2) s(-1), respectively. In addition, both agricultural and urban soils were observed to convert (15)NH4(+) to HO(15)NO. Genomic surveys of soil samples revealed that 1.5-6% of total expressed 16S rRNA sequences detected belonged to known ammonia oxidizing bacteria and archaea. Peak fluxes of HONO were directly related to the abundance of ammonia-oxidizer sequences, which in turn depended on soil pH. Peak HONO fluxes under fertilized conditions are comparable in magnitude to fluxes reported during field campaigns. The results suggest that biogenic HONO emissions will be important in soil environments that exhibit high nitrification rates (e.g., agricultural soil) although the widespread occurrence of ammonia oxidizers implies that biogenic HONO emissions are also possible in the urban and remote environment.

Dissipation of fragrance materials in sludge-amended soils.

PubMed

DiFrancesco, Angela M; Chiu, Pei C; Standley, Laurel J; Allen, Herbert E; Salvito, Daniel T

2004-01-01

A possible removal mechanism for fragrance materials (FMs) in wastewater is adsorption to sludge, and sludge application to land may be a route through which FMs are released to the soil environment. However, little is known about the concentrations and fate of FMs in soil receiving sludge application. This study was conducted to better understand the dissipation of FMs in sludge-amended soils. We first determined the spiking and extraction efficiencies for 22 FMs in soil and leachate samples. Nine FMs were detected in digested sludges from two wastewater treatment plants in Delaware using these methods. We conducted a 1-year die-away experiment which involved four different soils amended with sludge, with and without spiking of the 22 FMs. The initial dissipation of FMs in all spiked trays was rapid, and only seven FMs remained at concentrations above the quantification limits after 3 months: AHTN, HHCB, musk ketone, musk xylene, acetyl cedrene, OTNE, and DPMI. After 1 year, the only FMs remaining in all spiked trays were musk ketone and AHTN. DPMI was the only FM that leached significantly from the spiked trays, and no FMs were detected in leachate from any unspiked tray. While soil organic matter content affected the dissipation rate in general, different mechanisms (volatilization, transformation, leaching) appeared to be important for different FMs.

Effect of Activated Carbon Amendment on Bacterial Community Structure and Functions in a PAH Impacted Urban Soil

PubMed Central

2012-01-01

We collected urban soil samples impacted by polycyclic aromatic hydrocarbons (PAHs) from a sorbent-based remediation field trial to address concerns about unwanted side-effects of 2% powdered (PAC) or granular (GAC) activated carbon amendment on soil microbiology and pollutant biodegradation. After three years, total microbial cell counts and respiration rates were highest in the GAC amended soil. The predominant bacterial community structure derived from denaturing gradient gel electrophoresis (DGGE) shifted more strongly with time than in response to AC amendment. DGGE band sequencing revealed the presence of taxa with closest affiliations either to known PAH degraders, e.g. Rhodococcus jostii RHA-1, or taxa known to harbor PAH degraders, e.g. Rhodococcus erythropolis, in all soils. Quantification by real-time polymerase chain reaction yielded similar dioxygenases gene copy numbers in unamended, PAC-, or GAC-amended soil. PAH availability assessments in batch tests showed the greatest difference of 75% with and without biocide addition for unamended soil, while the lowest PAH availability overall was measured in PAC-amended, live soil. We conclude that AC had no detrimental effects on soil microbiology, AC-amended soils retained the potential to biodegrade PAHs, but the removal of available pollutants by biodegradation was most notable in unamended soil. PMID:22455603

Effect of activated carbon amendment on bacterial community structure and functions in a PAH impacted urban soil.

PubMed

Meynet, Paola; Hale, Sarah E; Davenport, Russell J; Cornelissen, Gerard; Breedveld, Gijs D; Werner, David

2012-05-01

We collected urban soil samples impacted by polycyclic aromatic hydrocarbons (PAHs) from a sorbent-based remediation field trial to address concerns about unwanted side-effects of 2% powdered (PAC) or granular (GAC) activated carbon amendment on soil microbiology and pollutant biodegradation. After three years, total microbial cell counts and respiration rates were highest in the GAC amended soil. The predominant bacterial community structure derived from denaturing gradient gel electrophoresis (DGGE) shifted more strongly with time than in response to AC amendment. DGGE band sequencing revealed the presence of taxa with closest affiliations either to known PAH degraders, e.g. Rhodococcus jostii RHA-1, or taxa known to harbor PAH degraders, e.g. Rhodococcus erythropolis, in all soils. Quantification by real-time polymerase chain reaction yielded similar dioxygenases gene copy numbers in unamended, PAC-, or GAC-amended soil. PAH availability assessments in batch tests showed the greatest difference of 75% with and without biocide addition for unamended soil, while the lowest PAH availability overall was measured in PAC-amended, live soil. We conclude that AC had no detrimental effects on soil microbiology, AC-amended soils retained the potential to biodegrade PAHs, but the removal of available pollutants by biodegradation was most notable in unamended soil. © 2012 American Chemical Society

76 FR 29238 - Methyl Bromide; Cancellation Order for Registration Amendments To Terminate Certain Soil Uses

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-20

... Order for Registration Amendments To Terminate Certain Soil Uses AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces EPA's order for the amendments to terminate soil... Corporation. 8536-05 Pic-Brom 33 Soil Chemicals Corporation d/b/a Cardinal Professional Products. [[Page 29239...

Soil biochar amendment shapes the composition of N2O-reducing microbial communities.

PubMed

Harter, Johannes; Weigold, Pascal; El-Hadidi, Mohamed; Huson, Daniel H; Kappler, Andreas; Behrens, Sebastian

2016-08-15

Soil biochar amendment has been described as a promising tool to improve soil quality, sequester carbon, and mitigate nitrous oxide (N2O) emissions. N2O is a potent greenhouse gas. The main sources of N2O in soils are microbially-mediated nitrogen transformation processes such as nitrification and denitrification. While previous studies have focused on the link between N2O emission mitigation and the abundance and activity of N2O-reducing microorganisms in biochar-amended soils, the impact of biochar on the taxonomic composition of the nosZ gene carrying soil microbial community has not been subject of systematic study to date. We used 454 pyrosequencing in order to study the microbial diversity in biochar-amended and biochar-free soil microcosms. We sequenced bacterial 16S rRNA gene amplicons as well as fragments of common (typical) nosZ genes and the recently described 'atypical' nosZ genes. The aim was to describe biochar-induced shifts in general bacterial community diversity and taxonomic variations among the nosZ gene containing N2O-reducing microbial communities. While soil biochar amendment significantly altered the 16S rRNA gene-based community composition and structure, it also led to the development of distinct functional traits capable of N2O reduction containing typical and atypical nosZ genes related to nosZ genes found in Pseudomonas stutzeri and Pedobacter saltans, respectively. Our results showed that biochar amendment can affect the relative abundance and taxonomic composition of N2O-reducing functional microbial traits in soil. Thus these findings broaden our knowledge on the impact of biochar on soil microbial community composition and nitrogen cycling. Copyright © 2016 Elsevier B.V. All rights reserved.

Sorption and transport of five sulfonamide antibiotics in agricultural soil and soil-manure systems.

PubMed

Wang, Na; Guo, Xinyan; Xu, Jing; Hao, Lijun; Kong, Deyang; Gao, Shixiang

2015-01-01

Animal manure application is a main spreading route of veterinary antibiotics in soil and groundwater. The sorption and leaching behavior of five commonly used sulfonamides in five typical soil and soil/manure mixtures from China were investigated in this study. Results showed that the empirical Freundlich equation fits well the sorption behavior of selected sulfonamides (r(2) was between 0.803 and 0.999, 1/n was between 0.68 and 1.44), and pH and soil organic carbon (OC) were the key impact factors to sorption and leaching. Addition of manure was found to increase the Kd values of sulfonamides in five different soils, following the rules that the more polar substances, the more increased extent of sorption after manure amendment (5.87 times for sulfadiazine with Log Kow = -0.09, and 2.49 times for sulfamethoxazole with Log Kow = 0.89). When the simulated rainfall amount reached 300 mL (180 mm), sulfonamides have high migration potential to the groundwater, especially in the soil with low OC and high pH. However, manure amendment increased the sorption capacity of sulfonamides in the top layer, thus it might play a role in decreasing the mobility of sulfonamides in soils. The systematic study would be more significant to assess the ecological risks and suggest considering the influence of manure amendment for the environmental fate of antibiotics.

Potential effects of vinasse as a soil amendment to control runoff and soil loss

NASA Astrophysics Data System (ADS)

Hazbavi, Z.; Sadeghi, S. H. R.

2016-02-01

Application of organic materials are well known as environmental practices in soil restoration, preserving soil organic matter and recovering degraded soils of arid and semiarid lands. Therefore, the present research focused on evaluating the effectiveness of vinasse, a byproduct mainly of the sugar-ethanol industry, on soil conservation under simulated rainfall. Vinasse can be recycled as a soil amendment due to its organic matter content. Accordingly, the laboratory experiments were conducted by using 0.25 m2 experimental plots at 20 % slope and rainfall intensity of 72 mm h-1 with 0.5 h duration. The effect of vinasse was investigated on runoff and soil loss control. Experiments were set up as a control (with no amendment) and three treated plots with doses of 0.5, 1, and 1.5 L m-2 of vinasse subjected to simulated rainfall. Laboratory results indicated that vinasse at different levels could not significantly (P > 0.05) decrease the runoff amount and soil loss rate in the study plots compared to untreated plots. The average amounts of minimum runoff volume and soil loss were about 3985 mL and 46 g for the study plot at a 1 L m-2 level of vinasse application.

Fly ash for soil amelioration: A review on the influence of ash blending with inorganic and organic amendments

NASA Astrophysics Data System (ADS)

Ram, L. C.; Masto, R. E.

2014-01-01

Globally, fly ash (FA), generated in huge quantities from coal fired power plants is a problematic solid waste. Utilization of FA as an ameliorant for improving soil quality has received a great deal of attention over the past four decades, and many studies have been carried out worldwide. The silt-sized particles, low bulk density (BD), higher water holding capacity (WHC), favorable pH, and significant presence of plant nutrients in FA, make it a potential amendment for soils. The studies suggest enormous potential for the use of FA to improve cultivable, degraded/waste land, mine soil, landfills, and also to reclaim abandoned ash ponds, for agriculture and forestry. FA application improves the physical, chemical and biological qualities of soils to which it is applied. However, in some cases, depending on the characteristics of FA, the release of trace elements and soluble salts from FA to a soil-plant-human system could be a constraint. The effect is minimal in the case of weathered FA. The findings reflected the heterogeneity of ash characteristics, soil types, and agro-climatic conditions, thus a generalized conclusion on the impact of FA on plant species and soil quality is difficult. It is very important that the application of FA to soil must be very specific depending on the properties of the FA and soil. A considerable amount of research has been carried out to blend FA with varieties of organic and inorganic materials, like lime, gypsum, red mud, animal manure, poultry manure, sewage sludge, composts, press mud, vermicompost, biochar, bioinoculants, etc. Co-application of FA with these materials has much advantage: enhanced nutrient availability, decreased bioavailability of toxic metals, pH buffering, organic matter addition, microbial stimulation, overall improvement in the general health of the soil, etc. The performance of FA blending with organic and inorganic materials is better than FA alone treatments. Farm manure was found to be the most

Associations between soil bacterial community structure and nutrient cycling functions in long-term organic farm soils following cover crop and organic fertilizer amendment.

PubMed

Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

2016-10-01

Agricultural management practices can produce changes in soil microbial populations whose functions are crucial to crop production and may be detectable using high-throughput sequencing of bacterial 16S rRNA. To apply sequencing-derived bacterial community structure data to on-farm decision-making will require a better understanding of the complex associations between soil microbial community structure and soil function. Here 16S rRNA sequencing was used to profile soil bacterial communities following application of cover crops and organic fertilizer treatments in certified organic field cropping systems. Amendment treatments were hairy vetch (Vicia villosa), winter rye (Secale cereale), oilseed radish (Raphanus sativus), buckwheat (Fagopyrum esculentum), beef manure, pelleted poultry manure, Sustane(®) 8-2-4, and a no-amendment control. Enzyme activities, net N mineralization, soil respiration, and soil physicochemical properties including nutrient levels, organic matter (OM) and pH were measured. Relationships between these functional and physicochemical parameters and soil bacterial community structure were assessed using multivariate methods including redundancy analysis, discriminant analysis, and Bayesian inference. Several cover crops and fertilizers affected soil functions including N-acetyl-β-d-glucosaminidase and β-glucosidase activity. Effects, however, were not consistent across locations and sampling timepoints. Correlations were observed among functional parameters and relative abundances of individual bacterial families and phyla. Bayesian analysis inferred no directional relationships between functional activities, bacterial families, and physicochemical parameters. Soil functional profiles were more strongly predicted by location than by treatment, and differences were largely explained by soil physicochemical parameters. Composition of soil bacterial communities was predictive of soil functional profiles. Differences in soil function were

Assessment of trace element accumulation by earthworms in an orchard soil remediation study using soil amendments

USGS Publications Warehouse

Centofantia, Tiziana; Chaney, Rufus L.; Beyer, W. Nelson; McConnell, Laura L.; Davis, A. P.; Jackson, Dana

2016-01-01

This study assessed potential bioaccumulation of various trace elements in grasses and earthworms as a consequence of soil incorporation of organic amendments for in situ remediation of an orchard field soil contaminated with organochlorine and Pb pesticide residues. In this experiment, four organic amendments of differing total organic carbon content and quality (two types of composted manure, composted biosolids, and biochar) were added to a contaminated orchard field soil, planted with two types of grasses, and tested for their ability to reduce bioaccumulation of organochlorine pesticides and metals in earthworms. The experiment was carried out in 4-L soil microcosms in a controlled environment for 90 days. After 45 days of orchardgrass or perennial ryegrass growth, Lumbricus terrestris L. were introduced to the microcosms and exposed to the experimental soils for 45 days before the experiment was ended. Total trace element concentrations in the added organic amendments were below recommended safe levels and their phytoavailablity and earthworm availability remained low during a 90-day bioremediation study. At the end of the experiment, total tissue concentrations of Cu, Cd, Mn, Pb, and Zn in earthworms and grasses were below recommended safe levels. Total concentrations of Pb in test soil were similar to maximum background levels of Pb recorded in soils in the Eastern USA (100 mg kg−1 d.w.) because of previous application of orchard pesticides. Addition of aged dairy manure compost and presence of grasses was effective in reducing the accumulation of soil-derived Pb in earthworms, thus reducing the risk of soil Pb entry into wildlife food chains.

Effects of inorganic and organic amendment on soil chemical properties, enzyme activities, microbial community and soil quality in yellow clayey soil.

PubMed

Liu, Zhanjun; Rong, Qinlei; Zhou, Wei; Liang, Guoqing

2017-01-01

Understanding the effects of external organic and inorganic components on soil fertility and quality is essential for improving low-yielding soils. We conducted a field study over two consecutive rice growing seasons to investigate the effect of applying chemical fertilizer (NPK), NPK plus green manure (NPKG), NPK plus pig manure (NPKM), and NPK plus straw (NPKS) on the soil nutrient status, enzyme activities involved in C, N, P, and S cycling, microbial community and rice yields of yellow clayey soil. Results showed that the fertilized treatments significantly improved rice yields over the first three experimental seasons. Compared with the NPK treatment, organic amendments produced more favorable effects on soil productivity. Notably, the NPKM treatment exhibited the highest levels of nutrient availability, microbial biomass carbon (MBC), activities of most enzymes and the microbial community. This resulted in the highest soil quality index (SQI) and rice yield, indicating better soil fertility and quality. Significant differences in enzyme activities and the microbial community were observed among the treatments, and redundancy analysis showed that MBC and available N were the key determinants affecting the soil enzyme activities and microbial community. The SQI score of the non-fertilized control (0.72) was comparable to that of the NPK (0.77), NPKG (0.81) and NPKS (0.79) treatments but significantly lower compared with NPKM (0.85). The significant correlation between rice yield and SQI suggests that SQI can be a useful to quantify soil quality changes caused by different agricultural management practices. The results indicate that application of NPK plus pig manure is the preferred option to enhance SOC accumulation, improve soil fertility and quality, and increase rice yield in yellow clayey soil.

Amending the seedling bed of eggplant with biochar can further immobilize Cd in contaminated soils.

PubMed

Li, Zhongyang; Qi, Xuebin; Fan, Xiangyang; Du, Zhenjie; Hu, Chao; Zhao, Zhijuan; Isa, Yunusa; Liu, Yuan

2016-12-01

Untreated municipal sewage is a potential source of Cd but has been used for irrigating vegetables in many countries in recent years. In growing vegetables and fruits in greenhouses, seedling breeding method is generally used in which the seedlings are transplanted into soils together with their seedling culture. Biochar has been increasingly used to amend soils contaminated by heavy metals, but there are few studies on the effectiveness of different ways of applying the biochar. In this paper, we investigated the efficacy of immobilizing Cd by amending eggplant seedling bed with biochar before transplanting them to biochar-amended soil contaminated by Cd. The results showed that, in comparison with traditional seedling method (without adding biochar), amending the seedling bed by biochar not only had a positive effect on plant growth and production, but further reduced the Cd concentration in the roots, shoots and the fruits by 12.2%, 12.5% and 18.5%, respectively. Furthermore, it increased the pH in rhizosphere to 8.83, reduced the exchangeable Cd concentration in soil by 28.6%, and decreased the Cd bio-accumulation factor from 0.36 to 0.32. Phytochelatin synthesis could be induced when plants are exposed to Cd and it has been used in the literature as a biomarker for evaluating metal toxicity. Our results showed that the seedling culture amended with biochar reduced phytochelatin synthesis in both roots and shoots. It can therefore be concluded that amending the eggplant seedlings bed with biochar can further enhance the effectiveness of remediating Cd contamination in soil after transplanting the plants into soil also amended with biochar. We found a new method to further immobilize Cd in contaminated soils by amending the seedling bed with biochar. Copyright © 2016. Published by Elsevier B.V.

Thermal destruction of organic waste hydrophobicity for agricultural soils application.

PubMed

Comino, Francisco; Aranda, Víctor; Domínguez-Vidal, Ana; Ayora-Cañada, María José

2017-11-01

Use of organic amendments is a good strategy for combating the growing problem of soil degradation due to deterioration of organic matter content, particularly severe in semi-arid European Mediterranean regions, while at the same time providing an opportunity for recycling organic wastes. Olive mill pomace (OMP), the main by-product of the olive oil industry, is being used increasingly in olive grove soils for this purpose. Although the positive effects of OMP amendments have been widely studied, they also have some negative effects on soil. One of the most critical is that they increase water repellency (WR) due to the presence of poorly evolved, strongly aliphatic compounds. This detrimental effect has received very little attention, although it may impair plant water availability and infiltration rates, increase erosion and lower long-term soil quality. This study proposed, for the first time, thermal treatment as an effective way of reducing WR in organic amendments (i.e. mixtures of OMP, olive tree pruning, chicken manure and spent coffee grounds) prior to their application to soil. Thermal treatment at 275 °C proved effective in removing WR, while lower temperatures (175 or 225 °C) can even increase it. Changes by thermal treatment in the characteristics of the organic amendments studied with FTIR and UV-Vis spectroscopy and thermogravimetric analysis showed that it strongly reduced the aliphatic compounds mainly responsible for their hydrophobicity, concentrated aromatic compounds and increased thermostability. Heating also reduced phytotoxicity, making all of the organic amendments usable in the field (germination index over 100%). Therefore, heating at 275 °C could be an acceptable option for removing WR from organic amendments, enhancing their quality with more stable evolved characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Zeolite Combined with Alum and Polyaluminum Chloride Mixed with Agricultural Slurries Reduces Carbon Losses in Runoff from Grassed Soil Boxes.

PubMed

Murnane, J G; Brennan, R B; Fenton, O; Healy, M G

2016-11-01

Carbon (C) losses from agricultural soils to surface waters can migrate through water treatment plants and result in the formation of disinfection by-products, which are potentially harmful to human health. This study aimed to quantify total organic carbon (TOC) and total inorganic C losses in runoff after application of dairy slurry, pig slurry, or milk house wash water (MWW) to land and to mitigate these losses through coamendment of the slurries with zeolite (2.36-3.35 mm clinoptilolite) and liquid polyaluminum chloride (PAC) (10% AlO) for dairy and pig slurries or liquid aluminum sulfate (alum) (8% AlO) for MWW. Four treatments under repeated 30-min simulated rainfall events (9.6 mm h) were examined in a laboratory study using grassed soil runoff boxes (0.225 m wide, 1 m long; 10% slope): control soil, unamended slurries, PAC-amended dairy and pig slurries (13.3 and 11.7 kg t, respectively), alum-amended MWW (3.2 kg t), combined zeolite and PAC-amended dairy (160 and 13.3 kg t zeolite and PAC, respectively) and pig slurries (158 and 11.7 kg t zeolite and PAC, respectively), and combined zeolite and alum-amended MWW (72 and 3.2 kg t zeolite and alum, respectively). The unamended and amended slurries were applied at net rates of 31, 34, and 50 t ha for pig and dairy slurries and MWW, respectively. Significant reductions of TOC in runoff compared with unamended slurries were measured for PAC-amended dairy and pig slurries (52 and 56%, respectively) but not for alum-amended MWW. Dual zeolite and alum-amended MWW significantly reduced TOC in runoff compared with alum amendment only. We conclude that use of PAC-amended dairy and pig slurries and dual zeolite and alum-amended MWW, although effective, may not be economically viable to reduce TOC losses from organic slurries given the relatively low amounts of TOC measured in runoff from unamended slurries compared with the amounts applied. Copyright © by the American Society of Agronomy, Crop Science Society of

Chromium fractionation and plant availability in tannery-sludge amended soil

NASA Astrophysics Data System (ADS)

Allué, Josep; Moya Garcés, Alba; Bech, Jaume; Barceló, Juan; Poschenrieder, Charlotte

2013-04-01

The leather industry represents an important economic sector in both developed and developing countries. Chromium tanning is the major process used to obtain high quality leather. Within the REACH regulation the use of Cr, especially CrVI, in the tanning process is under discussion in Europe. High Cr concentration in shoes and other Cr-tanned leather products can cause contact dermatitis in sensitive population. Moreover, the high Cr concentration is the major limiting factor for the use of tannery sludge as a source of organic matter in agricultural soils. Interest in Cr, however is not limited to its potential toxic effects. Chromium III is used as a dietary supplement because there are reports, but also controversy, about the positive effects of Cr III in glucose tolerance and type-2 diabetes. Adequate intake levels for Cr by the diet have been established between 25 and 35 µg/day for adult females and males, respectively. Sufficient supply of Cr III by the diet is preferable to the use of CrIII-salt based dietary supplements. The objective of the present work was to investigate whether Cr from tannery sludge-amended soil is available to Trigonella foenum-graecum plants, a plant used both as a spice and as a medicinal herb, because of its hypoglucemic effects. For this purpose clay loam soil (pH 7.8) was sieved (2mm) and thoroughly mixed with tannery sludge from a depuration station (Igualadina Depuració i Recuperació S.L., Igualada, Barcelona, Spain). The sludge had a Cr concentration of 6,034mg kg-1 and a 0.73 % of NH4-nitrogen. All the Cr was in the form of CrIII. Three treatments were disposed. Control soil receiving no sludge, a 60 mg kg-1 Cr treatment (10 g fresh sludge kg-1 soil) and a 120 mg kg-1 Cr treatment (20 g fresh sludge kg-1 soil). Control soil and the soil treated with 10g kg-1 sludge received NPK fertilizer in the form of ammonium sulfate, superfosfate, and KCl to rise the N,P, and K concentrations to similar levels to those achieved in the

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils.

PubMed

Ali, Muhammad Aslam; Kim, P J; Inubushi, K

2015-10-01

Effects of different soil amendments were investigated on methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK+fly ash, NPK+silicate slag, NPK+phosphogypsum(PG), NPK+blast furnace slag (BFS), NPK+revolving furnace slag (RFS), NPK+silicate slag (50%)+RFS (50%), NPK+biochar, NPK+biochar+Azolla-cyanobacteria, NPK+silicate slag+Azolla-cyanobacteria, NPK+phosphogypsum (PG)+Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N2O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH4 emissions were significantly increased by 9.5-14.0% with biochar amendments, however, global warming potentials were decreased by 8.0-12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0-30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43-50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of carbonaceous soil amendments on potential mobility of weak acid herbicides in soil

USDA-ARS?s Scientific Manuscript database

Use of carbonaceous amendments in soil has been proposed to decrease potential offsite transport of weak acid herbicides and metabolites by increasing their sorption to soil. The effects of organic olive mill waste, biochars from different feed stocks, and humic acid bound to clay on sorption of MCP...

Agricultural waste utilisation strategies and demand for urban waste compost: Evidence from smallholder farmers in Ethiopia.

PubMed

Nigussie, Abebe; Kuyper, Thomas W; de Neergaard, Andreas

2015-10-01

The use of agricultural waste for soil amendment is limited in developing countries. Competition between fuel and feed is the major cause for the insufficient application of agricultural waste on cropland. The aims of this study were therefore (i) to investigate variation in agricultural waste allocation between groups of farmers with different livelihood strategies and link this allocation with the nutrient balances of their production systems, (ii) to identify farm characteristics that influence utilisation of agricultural waste for soil amendment, and (iii) to assess demand for urban waste compost. A total of 220 farmers were selected randomly and interviewed using standardised semi-structured questionnaires. Four groups of farmers, namely (i) field crop farmers, (ii) vegetable producers, (iii) ornamental-plant growers, and (iv) farmers practising mixed farming, were identified using categorical principal component and two-step cluster analyses. Field crop farmers produced the largest quantity of agricultural waste, but they allocated 80% of manure to fuel and 85% of crop residues to feed. Only <10% of manure and crop residues were applied on soils. Farmers also sold manure and crop residues, and this generated 5-10% of their annual income. Vegetable and ornamental-plant growers allocated over 40% of manure and crop residues to soil amendment. Hence, nutrient balances were less negative in vegetable production systems. Education, farm size, land tenure and access to extension services were the variables that impeded allocation of agricultural waste to soil amendment. Replacement of fuel and feed through sustainable means is a viable option for soil fertility management. Urban waste compost should also be used as alternative option for soil amendment. Our results showed variation in compost demand between farmers. Education, landownership, experience with compost and access to extension services explained variation in compost demand. We also demonstrated that

Weed seed inactivation in soil mesocosms via biosolarization with mature compost and tomato processing waste amendments.

PubMed

Achmon, Yigal; Fernández-Bayo, Jesús D; Hernandez, Katie; McCurry, Dlinka G; Harrold, Duff R; Su, Joey; Dahlquist-Willard, Ruth M; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

2017-05-01

Biosolarization is a fumigation alternative that combines passive solar heating with amendment-driven soil microbial activity to temporarily create antagonistic soil conditions, such as elevated temperature and acidity, that can inactivate weed seeds and other pest propagules. The aim of this study was to use a mesocosm-based field trial to assess soil heating, pH, volatile fatty acid accumulation and weed seed inactivation during biosolarization. Biosolarization for 8 days using 2% mature green waste compost and 2 or 5% tomato processing residues in the soil resulted in accumulation of volatile fatty acids in the soil, particularly acetic acid, and >95% inactivation of Brassica nigra and Solanum nigrum seeds. Inactivation kinetics data showed that near complete weed seed inactivation in soil was achieved within the first 5 days of biosolarization. This was significantly greater than the inactivation achieved in control soils that were solar heated without amendment or were amended but not solar heated. The composition and concentration of organic matter amendments in soil significantly affected volatile fatty acid accumulation at various soil depths during biosolarization. Combining solar heating with organic matter amendment resulted in accelerated weed seed inactivation compared with either approach alone. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Modulation of hexavalent chromium toxicity on Οriganum vulgare in an acidic soil amended with peat, lime, and zeolite.

PubMed

Antoniadis, Vasileios; Zanni, Anna A; Levizou, Efi; Shaheen, Sabry M; Dimirkou, Anthoula; Bolan, Nanthi; Rinklebe, Jörg

2018-03-01

Dynamics of chromate (Cr(VI)) in contaminated soils may be modulated by decreasing its phytoavailability via the addition of organic matter-rich amendments, which might accelerate Cr(VI) reduction to inert chromite (Cr(III)) or high-cation exchange capacity amendments. We studied Cr(VI) phytoavailability of oregano in a Cr(VI)-spiked acidic soil non-treated (S) and treated with peat (SP), lime (SL), and zeolite (SZ). The addition of Cr(VI) increased the concentrations of Cr(VI) and Cr(III) in soils and plants, especially in the lime-amended soil. The plant biomass decreased in the lime-amended soil compared to the un-spiked soil (control) due to decreased plant phosphorus concentrations and high Cr(VI) concentrations in root at that treatment. Oregano in the peat-amended soil exhibited significantly less toxic effects, due to the role of organic matter in reducing toxic Cr(VI) to Cr(III) and boosted plant vigour in this treatment. In the lime-amended soil, the parameters of soil Cr(VI), soil Cr(III), and root Cr(III) increased significantly compared to the non-amended soil, indicating that Cr(VI) reduction to Cr(III) was accelerated at high pH. Added zeolite failed to decreased Cr(VI) level to soil and plant. Oregano achieved a total uptake of Cr(III) and Cr(VI) of 0.275 mg in plant kg -1 soil in a pot in the non-amended soil. We conclude that peat as soil amendment might be considered as a suitable option for decreasing Cr(VI) toxicity in soil and plant, and that oregano as tolerant plant species has a certain potential to be used as a Cr accumulator. Copyright © 2017 Elsevier Ltd. All rights reserved.

Zinc distribution in soils amended with different kinds of sewage sludge.

PubMed

Torri, Silvana Irene; Lavado, Raúl

2008-09-01

Sewage sludge (SS) can be applied to cropland to supply and recycle nutrients and organic carbon. Potentially toxic elements in the sludge, however, are of environmental concern. This study evaluates the changes in chemical speciation of Zn in three representative pristine soils of the Pampas Region, Argentina, measured with sequential extraction over a one-year period. Pure SS or SS containing 30% (DM) of its own incineration ash (AS) was applied to the soils at an application rate of 150 Mg ha(-1). Zn was sequentially fractionated into exchangeable, organically bound, inorganic and residual fractions. The application of the SS and AS amendments significantly increased Zn concentration in all soil fractions at each sampling date. At day 1, Zn was mainly found in the residual fraction. A year after the application of the amendments, redistribution towards the inorganic fraction was observed (41-76% of total Zn content). Zn found in exchangeable and inorganic fractions depended on soil pH rather than on the type of soil used. A negative and significant correlation was found between exchangeable Zn concentrations and soil pH (r=0.94), and a positive and significant correlation between inorganic Zn concentrations and soil pH (r=0.92). For each amended soil and sampling date, no significant differences were observed between SS or AS treatments for the exchangeable fraction. Moreover, the use of AS did not cause significant differences in Zn concentration in the other soil fractions compared to SS. Based on these results, land spreading of AS may be similar to SS diaposal in terms of Zn mobility.

Degradation of organic pollutants in Mediterranean forest soils amended with sewage sludge.

PubMed

Francisca Gomez-Rico, M; Font, Rafael; Vera, Jose; Fuentes, David; Disante, Karen; Cortina, Jordi

2008-05-01

The degradation of two groups of organic pollutants in three different Mediterranean forest soils amended with sewage sludge was studied for nine months. The sewage sludge produced by a domestic water treatment plant was applied to soils developed from limestone, marl and sandstone, showing contrasting alkalinity and texture. The compounds analysed were: linear alkylbenzene sulphonates (LAS) with a 10-13 carbon alkylic chain, and nonylphenolic compounds, including nonylphenol (NP) and nonylphenol ethoxylates with one and two ethoxy groups (NP1EO+NP2EO). These compounds were studied because they frequently exceed the limits proposed for sludge application to land in Europe. After nine months, LAS decomposition was 86-96%, and NP+NP1EO+NP2EO decomposition was 61-84%, which can be considered high. Temporal trends in LAS and NP+NP1EO+NP2EO decomposition were similar, and the concentrations of both types of compounds were highly correlated. The decomposition rates were higher in the period of 6-9 months (summer period) than in the period 0-6 months (winter+spring period) for total LAS and NP+NP1EO+NP2EO. Differences in decay rates with regard to soil type were not significant. The average values of decay rates found are similar to those observed in agricultural soils.

Use of raw or incubated organic wastes as amendments in reducing pesticide leaching through soil columns.

PubMed

Marín-Benito, J M; Brown, C D; Herrero-Hernández, E; Arienzo, M; Sánchez-Martín, M J; Rodríguez-Cruz, M S

2013-10-01

Soil amendment with organic wastes is becoming a widespread management practice since it can effectively solve the problems of uncontrolled waste accumulation and improve soil quality. However, when simultaneously applied with pesticides, organic wastes can significantly modify the environmental behaviour of these compounds. This study evaluated the effect of sewage sludges (SS), grape marc (GM) and spent mushroom substrates (SMS) on the leaching of linuron, diazinon and myclobutanil in packed columns of a sandy soil with low organic matter (OM) content (<1%). Soil plus amendments had been incubated for one month (1 m) or 12 months (12 m). Data from the experimental breakthrough curves (BTCs) were fitted to the one-dimensional transport model CXTFIT 2.1. All three amendments reduced leaching of linuron and myclobutanil relative to unamended soil. SMS was the most effective in reducing leaching of these two compounds independent of whether soil was incubated for 1 m or 12 m. Soil amendments increased retardation coefficients (Rexp) by factors of 3 to 5 for linuron, 2 to 4 for diazinon and 3 to 5 for myclobutanil relative to unamended soil. Leaching of diazinon was relatively little affected by soil amendment compared to the other two compounds and both SS and SMS amendment with 1m incubation resulted in enhanced leaching of diazinon. The leaching data for linuron and myclobutanil were well described by CXTFIT (mean square error, MSE<4.9·10(-7) and MSE<7.0·10(-7), respectively) whereas those of diazinon were less well fitted (MSE<2.1·10(-6)). The BTCs for pesticides were similar in soils incubated for one month or one year, indicating that the effect of amendment on leaching persists over relatively long periods of time. Copyright © 2013 Elsevier B.V. All rights reserved.

Modelling the fate of PAH added with composts in amended soil according to the origin of the exogenous organic matter.

PubMed

Brimo, Khaled; Ouvrard, Stéphanie; Houot, Sabine; Lafolie, François; Garnier, Patricia

2018-03-01

A new model that was able to simulate the behaviours of polycyclic aromatic hydrocarbons (PAH) during composting and after the addition of the composts to agricultural soil is presented here. This model associates modules that describe the physical, biological and biochemical processes involved in PAH dynamics in soils, along with a module describing the compost degradation resulting in PAH release. The model was calibrated from laboratory incubations using three 14 C-PAHs, phenanthrene, fluoranthene and benzo(a)pyrene, and three different composts consisting of two mature and one non-mature composts. First, the labelled PAHs were added to the compost over 28days, and spiked composts were then added to the soil over 55days. The model calculates the proportion of biogenic and physically bound residues in the non-extractable compartment of PAHs at the end of the compost incubation to feed the initial conditions of the model for soil amended with composts. For most of the treatments, a single parameter set enabled to simulate the observed dynamics of PAHs adequately for all the amended soil treatments using a Bayesian approach. However, for fluoranthene, different parameters that were able to simulate the growth of a specific microbial biomass had to be considered for mature compost. Processes that occurred before the compost application to the soil strongly influenced the fate of PAHs in the soil. Our results showed that the PAH dissipation during compost incubation was higher in mature composts because of the higher specific microbial activity, while the PAH dissipation in amended soil was higher in the non-mature compost because of the higher availability of PAHs and the higher co-metabolic microbial activity. Copyright © 2017 Elsevier B.V. All rights reserved.

Green waste compost as an amendment during induced phytoextraction of mercury-contaminated soil.

PubMed

Smolinska, Beata

2015-03-01

Phytoextraction of mercury-contaminated soils is a new strategy that consists of using the higher plants to make the soil contaminant nontoxic. The main problem that occurs during the process is the low solubility and bioavailability of mercury in soil. Therefore, some soil amendments can be used to increase the efficiency of the Hg phytoextraction process. The aim of the investigation was to use the commercial compost from municipal green wastes to increase the efficiency of phytoextraction of mercury-contaminated soil by Lepidium sativum L. plants and determine the leaching of Hg after compost amendment. The result of the study showed that Hg can be accumulated by L. sativum L. The application of compost increased both the accumulation by whole plant and translocation of Hg to shoots. Compost did not affect the plant biomass and its biometric parameters. Application of compost to the soil decreased the leaching of mercury in both acidic and neutral solutions regardless of growing medium composition and time of analysis. Due to Hg accumulation and translocation as well as its potential leaching in acidic and neutral solution, compost can be recommended as a soil amendment during the phytoextraction of mercury-contaminated soil.

Bio-augmentation and nutrient amendment decrease concentration of mercury in contaminated soil.

PubMed

Mahbub, Khandaker Rayhan; Krishnan, Kannan; Andrews, Stuart; Venter, Henrietta; Naidu, Ravi; Megharaj, Mallavarapu

2017-01-15

Four mercury (Hg) contaminated soils with different pH (7.6, 8.5, 4.2 and 7.02) and total organic carbon contents (2.1, 2.2, 4 and 0.9%) were subjected to bioremediation utilizing a Hg volatilizing bacterial strain Sphingobium SA2 and nutrient amendment. In a field with ~280mg/kgHg, 60% of Hg was removed by bio-augmentation in 7days, and the removal was improved when nutrients were added. Whereas in artificially spiked soils, with ~100mg/kgHg, removal due to bio-augmentation was 33 to 48% in 14days. In the field contaminated soil, nutrient amendment alone without bio-augmentation removed 50% of Hg in 28days. Nutrient amendment also had an impact on Hg remediation in the spiked soils, but the best results were obtained when the strain and nutrients both were applied. The development of longer root lengths from lettuce and cucumber seeds grown in the remediated soils confirmed that the soil quality improved after bioremediation. This study clearly demonstrates the potential of Hg-reducing bacteria in remediation of Hg-contaminated soils. However, it is desirable to trap the volatilized Hg for enhanced bioremediation. Copyright © 2016 Elsevier B.V. All rights reserved.

The Effect of paper mill waste and sewage sludge amendments on soil organic matter

NASA Astrophysics Data System (ADS)

Méndez, Ana; Barriga, Sandra; Guerrero, Francisca; Gascó, Gabriel

2013-04-01

In general, Mediterranean soils have low organic matter content, due to the climate characteristics of this region and inadequate land management. Traditionally, organic wastes such as manure are used as amendment in order to improve the soil quality, increasing soil fertility by the accumulation of nitrogen, phosphorus and other plant nutrients in the soil. In the last decade, other anthropogenic organic wastes such as sewage sludge or paper waste materials have been studied as soil amendments to improve physical, chemical and biological properties of soils. The objective of the present work was to study the influence of waste from a paper mill and sewage sludge amendments on soil organic matter. For this reason, soil organic matter evolution was studied using thermogravimetric analysis (TGA), the derivative (dTG) and differential thermal analysis (DTA). Thermal analytical techniques have the advantage of using full samples without pre-treatments and have been extensively used to study the evolution of organic matter in soils, to evaluate composting process or to study the evolution of organic matter of growing media.

The influence of organic amendments on soil aggregate stability from semiarid sites

NASA Astrophysics Data System (ADS)

Hueso Gonzalez, Paloma; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

2016-04-01

Restoring the native vegetation is the most effective way to regenerate soil health. Under these conditions, vegetation cover in areas having degraded soils may be better sustained if the soil is amended with an external source of organic matter. The addition of organic materials to soils also increases infiltration rates and reduces erosion rates; these factors contribute to an available water increment and a successful and sustainable land management. The goal of this study was to analyze the effect of various organic amendments on the aggregate stability of soils in afforested plots. An experimental paired-plot layout was established in southern of Spain (homogeneous slope gradient: 7.5%; aspect: N170). Five amendments were applied in an experimental set of plots: straw mulching; mulch with chipped branches of Aleppo Pine (Pinus halepensis L.); TerraCotten hydroabsobent polymers; sewage sludge; sheep manure and control. Plots were afforested following the same spatial pattern, and amendments were mixed with the soil at the rate 10 Mg ha-1. The vegetation was planted in a grid pattern with 0.5 m between plants in each plot. During the afforestation process the soil was tilled to 25 cm depth from the surface. Soil from the afforested plots was sampled in: i) 6 months post-afforestation; ii) 12 months post-afforestation; iii) 18 months post-afforestation; and iv) 24 months post-afforestation. The sampling strategy for each plot involved collection of 4 disturbed soil samples taken from the surface (0-10 cm depth). The stability of aggregates was measured by wet-sieving. Regarding to soil aggregate stability, the percentage of stable aggregates has increased slightly in all the treatments in relation to control. Specifically, the differences were recorded in the fraction of macroaggregates (≥ 0.250 mm). The largest increases have been associated with straw mulch, pinus mulch and sludge. Similar results have been registered for the soil organic carbon content

Evaluation of ferrihydrite as amendment to restore an arsenic-polluted mine soil.

PubMed

Abad-Valle, P; Álvarez-Ayuso, E; Murciego, A

2015-05-01

The effectiveness of ferrihydrite as amendment to restore the soil habitat functioning of a soil polluted with As by mining activities was evaluated. Its influence on As mobility and phytoavailability was also assessed. Soil treated with increasing amendment doses (0, 1, 2, and 5 %) were analyzed for soil microbiological parameters such as basal soil respiration and dehydrogenase, β-glucosidase, urease, acid and alkaline phosphatase, and arylsulfatase activities. Batch leaching tests and plant growth experiments using ryegrass and alfalfa plants were performed. The treatment with ferrihydrite was effective to reduce As mobility and plant As uptake, translocation, and accumulation. Likewise, the soil microbiological status was generally improved as derived from basal soil respiration and dehydrogenase and acid and alkaline phosphatase activities, which showed increases up to 85, 45, 11, and 47 %, respectively, at a ferrihydrite addition rate of 5 %.

Extractability and Bioavailability of Pb and As in Historically Contaminated Orchard Soil: Effects of Compost Amendments

PubMed Central

Fleming, Margaret; Yiping, Tai; Ping, Zhuang; McBride, Murray B.

2015-01-01

The availability of Pb and As in an historically contaminated orchard soil, after amendment with compost and aging in the field, was determined by single-step chemical extraction with 1.0 M ammonium acetate at pH 4.8, sequential extraction using the modified BCR test, and a redworm bioassay in the laboratory. The efficiency of soil Pb extraction by ammonium acetate was greater at higher total soil Pb but was reduced by compost amendment. Conversely, the extraction efficiency of total soil As increased with compost amendment, but was not sensitive to total soil As. The redworm bioassay indicated Pb (but not As) bioavailability to be reduced by soil amendment with compost, a result consistent with the ammonium acetate extraction test but not reflected in modified BCR test. Electron microprobe studies of the orchard soil revealed Pb and As to be spatially associated in discrete particles along with phosphorus and iron. PMID:23474982

SITE Technology Capsule. Demonstration of Rocky Mountain Remediation Services Soil Amendment

EPA Science Inventory

This report briefly summarizes the Rocky Mountain Remediation Services treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical methods.

Biochar as possible long-term soil amendment for phytostabilisation of TE-contaminated soils.

PubMed

Bopp, Charlotte; Christl, Iso; Schulin, Rainer; Evangelou, Michael W H

2016-09-01

Soils contaminated by trace elements (TEs) pose a high risk to their surrounding areas as TEs can spread by wind and water erosion or leaching. A possible option to reduce TE transfer from these sites is phytostabilisation. It is a long-term and cost-effective rehabilitation strategy which aims at immobilising TEs within the soil by vegetation cover and amendment application. One possible amendment is biochar. It is charred organic matter which has been shown to immobilise metals due to its high surface area and alkaline pH. Doubts have been expressed about the longevity of this immobilising effect as it could dissipate once the carbonates in the biochar have dissolved. Therefore, in a pot experiment, we determined plant metal uptake by ryegrass (Lolium perenne) from three TE-contaminated soils treated with two biochars, which differed only in their pH (acidic, 2.80; alkaline, 9.33) and carbonate (0.17 and 7.3 %) content. Root biomass was increased by the application of the alkaline biochar due to the decrease in TE toxicity. Zinc and Cu bioavailability and plant uptake were equally reduced by both biochars, showing that surface area plays an important role in metal immobilisation. Biochar could serve as a long-term amendment for TE immobilisation even after its alkalinity effect has dissipated.

Do plant-based amendments improve soil physiochemical and microbiological properties and plant growth in dryland ecosystems?

NASA Astrophysics Data System (ADS)

Kneller, Tayla; Harris, Richard; Muñoz-Rojas, Miriam

2017-04-01

Background Land intensive practices including mining have contributed to the degradation of landscapes globally. Current challenges in post-mine restoration revolve around the use of substrates poor in organic materials (e.g. overburden and waste rock) and lack of original topsoil which may result in poor seedling recruitment and in later stages in soil nutrient deficiency, metal toxicity, decreased microbial activity and high salinity (Bateman et al., 2016; Muñoz-Rojas et al., 2016). Despite continuous efforts and advances we have not proportionally advanced our capability to successfully restore these landscapes following mining. Recent attempts to improve plant establishment in arid zone restoration programs have included the application of plant based amendments to soil profiles. This approach usually aims to accelerate soil reconstruction via improvement of soil aggregate stability and increase of soil organic carbon, and water holding capacity. Whilst a significant amount of recent research has focused on the application of such amendments, studies on the potential application of plant based materials to recover soil functionality and re-establish plant communities in post-mined landscapes in arid regions are limited. Here we will discuss our work investigating the application of a plant based amendment on soil substrates commonly used in post mining restoration in the Pilbara region, Western Australia. Methodology The study was conducted in a glasshouse facility where environmental conditions were continuously monitored. Using two growth materials (topsoil and waste rock) and a plant based amendment (dry biomass of the most common grass in the Pilbara, Triodia wiseana) five different treatments were tested. Treatments consisted of control soil treatments (topsoil, waste and a mixture of the former soil types (mixture)) and two amended soil treatments (waste amended and mixture amended). Additionally, three different vegetation communities were studies

DETERMINING SPECIATION OF PB IN PHOSPHATE AMENDED SOILS: METHOD LIMITATIONS

EPA Science Inventory

Determining the effectiveness of in-situ immobilization for P-amended, Pb-contaminated soils has typically relied on non-spectroscopic methods that in recent years have come under scrutiny due to technical and unforeseen error issues. In this study, we analyzed 18 soil samples vi...

Arsenic uptake by lettuce from As-contaminated soil remediated with Pteris vittata and organic amendment.

PubMed

de Oliveira, Letuzia M; Suchismita, Das; Gress, Julia; Rathinasabapathi, Bala; Chen, Yanshan; Ma, Lena Q

2017-06-01

Leaching of inorganic arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil As levels. Thus, an environmental concern arises regarding As accumulation in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to investigate the ability of As-hyperaccumulator P. vittata and organic amendments in reducing As uptake by lettuce (Lactuca sativa) from a soil contaminated from CCA-treated wood (63.9 mg kg -1 As). P. vittata was grown for 150 d in a CCA-contaminated soil amended with biochar, activated carbon or coffee grounds at 1%, followed by lettuce for another 55 d. After harvest, plant biomass and As concentrations in plant and soil were determined. The presence of P. vittata reduced As content in lettuce by 21% from 27.3 to 21.5 mg kg -1 while amendment further reduced As in lettuce by 5.6-18%, with activated C being most effective. Our data showed that both P. vittata and organic amendments were effective in reducing As concentration in lettuce. Though no health-based standard for As in vegetables exists in USA, care should be taken when growing lettuce in contaminated soils. Our data showed that application of organic amendments with P. vittata reduced As hazards in CCA-contaminated soils. Published by Elsevier Ltd.

Survival and persistence of non-pathogenic Escherichia coli and attenuated Escherichia coli O157:H7 in soils amended with animal manure in a greenhouse environment

USDA-ARS?s Scientific Manuscript database

Biological soil amendments (BSA's), including dairy cattle, poultry litter, and horse manure, play an important role in agriculture but may contain pathogens that can contaminate raw or ready-to-eat fruit and vegetable crops that are consumed raw. Proposed FDA standards include a 90- or 120-day inte...

Recovery of a soil degraded by deep excavation using plantation of tree species and a cellulose by-product as amendment

NASA Astrophysics Data System (ADS)

Guimarães Giácomo, Rômulo; Alves, Marlene Cristina; Paz-Ferreiro, Jorge

2014-05-01

Organic by-products obtained from the cellulose industry have been used as costs effective fertilizers in agricultural and forest soils and also as amendments for recovery of abandoned land. The construction of a power plant in the Paraná River (Brazil) motivates the deep excavation of a soil profile under native forest. Once exposed, the saprolite beneath the natural soil was abandoned, without any reclamation measure. The land left after engineering works was a harsh environment, where secondary vegetation hardly or not at all recovered. The objective of this study was to tests the efficiency of recycling a composted product obtained from cellulose waste to reclaim the abandoned saprolite material. A field trial was carried out following a classical split-split plot experimental design. In this design plantations plantations of Eucalyptus urograndis (a hybrid Eucalyptus species, considered here as exotic) and Mabea fistulifera (a native species) were the main plots. Within each main plot, subplots were six fertilizer treatments including an external control treatment, without any intervention, a control treatment, without fertilization, a mineral fertilizer treatment and three treatments amended with compost from cellulose applied at the rates of 10, 15 and 20 Mg ha-1. There were four replications per treatment. The recovery of the soil profile under the different treatments studied was assessed by indices obtained from analysis of soil physical and chemical properties. Variables such as tree species development, litter and plant debris fall, return of nutrients from vegetation to soil and epigeal fauna were also characterized. Increasing dose of amendment with cellulose by-product showed a trend to improve water infiltration and soil resistance to penetration. Treatment with 20 Mg ha-1of cellulose compost showed the highest nutrient availability, but also exhibited an important increase in soil pH. The greatest development of planted trees was recorded in the

Intensive agriculture reduces soil biodiversity across Europe.

PubMed

Tsiafouli, Maria A; Thébault, Elisa; Sgardelis, Stefanos P; de Ruiter, Peter C; van der Putten, Wim H; Birkhofer, Klaus; Hemerik, Lia; de Vries, Franciska T; Bardgett, Richard D; Brady, Mark Vincent; Bjornlund, Lisa; Jørgensen, Helene Bracht; Christensen, Sören; Hertefeldt, Tina D'; Hotes, Stefan; Gera Hol, W H; Frouz, Jan; Liiri, Mira; Mortimer, Simon R; Setälä, Heikki; Tzanopoulos, Joseph; Uteseny, Karoline; Pižl, Václav; Stary, Josef; Wolters, Volkmar; Hedlund, Katarina

2015-02-01

Soil biodiversity plays a key role in regulating the processes that underpin the delivery of ecosystem goods and services in terrestrial ecosystems. Agricultural intensification is known to change the diversity of individual groups of soil biota, but less is known about how intensification affects biodiversity of the soil food web as a whole, and whether or not these effects may be generalized across regions. We examined biodiversity in soil food webs from grasslands, extensive, and intensive rotations in four agricultural regions across Europe: in Sweden, the UK, the Czech Republic and Greece. Effects of land-use intensity were quantified based on structure and diversity among functional groups in the soil food web, as well as on community-weighted mean body mass of soil fauna. We also elucidate land-use intensity effects on diversity of taxonomic units within taxonomic groups of soil fauna. We found that between regions soil food web diversity measures were variable, but that increasing land-use intensity caused highly consistent responses. In particular, land-use intensification reduced the complexity in the soil food webs, as well as the community-weighted mean body mass of soil fauna. In all regions across Europe, species richness of earthworms, Collembolans, and oribatid mites was negatively affected by increased land-use intensity. The taxonomic distinctness, which is a measure of taxonomic relatedness of species in a community that is independent of species richness, was also reduced by land-use intensification. We conclude that intensive agriculture reduces soil biodiversity, making soil food webs less diverse and composed of smaller bodied organisms. Land-use intensification results in fewer functional groups of soil biota with fewer and taxonomically more closely related species. We discuss how these changes in soil biodiversity due to land-use intensification may threaten the functioning of soil in agricultural production systems. © 2014 John Wiley

Impact of rice-straw biochars amended soil on the biological Si cycle in soil-plant ecosystem

NASA Astrophysics Data System (ADS)

Li, Zimin; Delvaux, Bruno; Struyf, Eric; Unzué-Belmonte, Dácil; Ronsse, Frederik; Cornelis, Jean-Thomas

2017-04-01

Biochar used as soil amendment can enhance soil fertility and plant growth. It may also contribute to increase the plant mineralomass of silicon (Si). However, very little studies have focused on the plant Si cycling in biochar amended soils. Here, we study the impact of two contrasting biochars derived from rice straws on soil Si availability and plant Si uptake. Rice plants were grown in a hydroponic device using Yoshida nutrient solution, respectively devoid of H4SiO4 (0 ppm Si: Si-) and enriched with it (40 ppm Si: Si+). After 12 weeks, the plants were harvested for further pyrolysis, conducted with holding time of 1h at 500˚ C. The respective rice-biochars are Si-/biochar and Si+/biochar. They exhibit contrasting phytolith contents (0.3 g Si kg-1 vs. 51.3 g Si kg-1), but identical physico-chemical properties. They were applied in two soils differing in weathering stage: a weathered Cambisol (CA) and a highly weathered Nitisol (NI). We then studied the effects of the amended biochar on CaCl2 extractable Si using a 64-days kinetic approach, on the content of soil biogenic Si, and on the uptake of Si by wheat plants grown for 5 weeks. We also quantified Si mineralomass in plants. We compared the effects of biochars to that of wollastonite (Wo)-(CaSiO3), a common Si-fertilizer. Our results show that Si+/biochar significantly increase the content of BSi in both soils. In CA, the cumulative content of CaCl2 extractable Si amounts to 85 mg kg-1 after Si+/biochar amendment, which is below the amount extracted after Wo application (100 mg kg-1). In contrast, in NI, the cumulative content of CaCl2 extractable Si is 198 mg kg-1 in the Si+/biochar amended treatment, which is far above the one measured after Wo application (93 mg kg-1). The Si-/biochar has no effect on the cumulative content of CaCl2 extractable Si in either soil type. Biochars and wollastonite increase the biomass of wheat on both soils. The increase is, however, larger in NI than in CA. In terms of Si

Effect of dairy manure rate and the stabilization time of amended soils on atrazine degradation.

PubMed

Aguilera, Paula; Briceño, Gabriela; Candia, Maribel; Mora, Maria de la Luz; Demanet, Rolando; Palma, Graciela

2009-10-01

The application rate of liquid cow manure (LCM) in the field and the stabilization time of amended soils before application of pre-plant herbicides are factors that determine their efficiency. This study includes evaluation of residual atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) in soil and amended soils with equivalent rate of 100,000; 200,000; and 300,000 L ha(-1) of LCM and the effect of pre-incubation time of amended soils on atrazine degradation. The study was carried out under controlled conditions using an Andisol with previous historical application of atrazine. The respiratory activity and fluorescein diacetate (FDA) studies indicated that the time necessary for stabilization of amended soils is over 20-30 d. During the measurement of respiratory and FDA activity, no significant differences were observed when atrazine was applied. The half-life of atrazine ranged from 5 to 8d and the relative distribution of degradation products seem to be affected by the application of LCM. The pre-incubation time of amended soil and LCM dose would not affect atrazine degradation rate, when the soil has a history of herbicide application. However, repeated applications of LCM in a long period of time could change the soil pH and increase the content of dissolved organic carbon (DOC) which could further contribute to a faster degradation of atrazine. Both effects would reduce the effectiveness of atrazine in weed control.

Behaviors of heavy metals (Cd, Cu, Ni, Pb and Zn) in soil amended with composts.

PubMed

Gusiatin, Zygmunt Mariusz; Kulikowska, Dorota

2016-09-01

This study investigated how amendment with sewage sludge compost of different maturation times (3, 6, 12 months) affected metal (Cd, Cu, Ni, Pb, Zn) bioavailability, fractionation and redistribution in highly contaminated sandy clay soil. Metal transformations during long-term soil stabilization (35 months) were determined. In the contaminated soil, Cd, Ni and Zn were predominately in the exchangeable and reducible fractions, Pb in the reducible fraction and Cu in the reducible, exchangeable and oxidizable fractions. All composts decreased the bioavailability of Cd, Ni and Zn for up to 24 months, which indicates that cyclic amendment with compost is necessary. The bioavailability of Pb and Cu was not affected by compost amendment. Based on the reduced partition index (IR), metal stability in amended soil after 35 months of stabilization was in the following order: Cu > Ni = Pb > Zn > Cd. All composts were more effective in decreasing Cd, Ni and Zn bioavailability than in redistributing the metals, and increasing Cu redistribution more than that of Pb. Thus, sewage sludge compost of as little as 3 months maturation can be used for cyclic amendment of multi-metal-contaminated soil.

Occurrence and distribution of sulfonamides, tetracyclines, quinolones, macrolides, and nitrofurans in livestock manure and amended soils of Northern China.

PubMed

Hou, Jie; Wan, Weining; Mao, Daqing; Wang, Chong; Mu, Quanhua; Qin, Songyan; Luo, Yi

2015-03-01

A feasible and rapid analysis for the simultaneous determination of sulfonamides (SAs), tetracyclines (TCs), fluoroquinolones (FQs), macrolides (MACs) and nitrofurans (NFs) in livestock manure and soils was established by solid-phase extraction (SPE)-ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS). A total of 32 manure and 17 amended soil samples from the Liaoning and Tianjin areas in Northern China were collected for analysis. The largest detected frequencies and concentrations in manure samples were those of TCs (3326.6 ± 12,302.6 μg/kg), followed by FQs (411.3 ± 1453.4 μg/kg), SAs (170.6 ± 1060.2 μg/kg), NFs (85.1 ± 158.1 μg/kg), and MACs (1.4 ± 4.8 μg/kg). In general, veterinary antibiotics (VAs) were detected with higher concentrations in swine and chicken manure than in cattle manure, reflecting the heavy usage of VAs in swine and chicken husbandry in the studied area. Furthermore, higher residues of antibiotics were found in piglet and fattening swine manure than in sow manure. In addition, TCs were the most frequently (100%) detected antibiotics in amended soil with higher concentrations (up to 10,967.1 μg/kg) than any other VAs. The attenuation of SAs was more obvious than TCs in amended soil after fertilization, which can most likely be attributed to the stronger sorption of TCs than SAs to soil organic matter through cation exchange. This study illustrated the prevalence of TCs detected in both animal manure and fertilized agricultural soils in Northern China, which may increase the risk to human health through the food chain. Thus, TCs should be given more attention in the management of veterinary usage in livestock husbandry.

Effects of inorganic and organic amendment on soil chemical properties, enzyme activities, microbial community and soil quality in yellow clayey soil

PubMed Central

Liu, Zhanjun; Rong, Qinlei; Zhou, Wei; Liang, Guoqing

2017-01-01

Understanding the effects of external organic and inorganic components on soil fertility and quality is essential for improving low-yielding soils. We conducted a field study over two consecutive rice growing seasons to investigate the effect of applying chemical fertilizer (NPK), NPK plus green manure (NPKG), NPK plus pig manure (NPKM), and NPK plus straw (NPKS) on the soil nutrient status, enzyme activities involved in C, N, P, and S cycling, microbial community and rice yields of yellow clayey soil. Results showed that the fertilized treatments significantly improved rice yields over the first three experimental seasons. Compared with the NPK treatment, organic amendments produced more favorable effects on soil productivity. Notably, the NPKM treatment exhibited the highest levels of nutrient availability, microbial biomass carbon (MBC), activities of most enzymes and the microbial community. This resulted in the highest soil quality index (SQI) and rice yield, indicating better soil fertility and quality. Significant differences in enzyme activities and the microbial community were observed among the treatments, and redundancy analysis showed that MBC and available N were the key determinants affecting the soil enzyme activities and microbial community. The SQI score of the non-fertilized control (0.72) was comparable to that of the NPK (0.77), NPKG (0.81) and NPKS (0.79) treatments but significantly lower compared with NPKM (0.85). The significant correlation between rice yield and SQI suggests that SQI can be a useful to quantify soil quality changes caused by different agricultural management practices. The results indicate that application of NPK plus pig manure is the preferred option to enhance SOC accumulation, improve soil fertility and quality, and increase rice yield in yellow clayey soil. PMID:28263999

Impact of Amendments on the Physical Properties of Soil under Tropical Long-Term No Till Conditions.

PubMed

Carmeis Filho, Antonio C A; Crusciol, Carlos A C; Guimarães, Tiara M; Calonego, Juliano C; Mooney, Sacha J

2016-01-01

Tropical regions have been considered the world's primary agricultural frontier; however, some physico-chemical deficiencies, such as low soil organic matter content, poor soil structure, high erodibility, soil acidity, and aluminum toxicity, have affected their productive capacity. Lime and gypsum are commonly used to improve soil chemical fertility, but no information exists about the long-term effects of these products on the physical attributes and C protection mechanisms of highly weathered Oxisols. A field trial was conducted in a sandy clay loam (kaolinitic, thermic Typic Haplorthox) under a no-tillage system for 12 years. The trial consisted of four treatments: a control with no soil amendment application, the application of 2.1 Mg ha-1 phosphogypsum, the application of 2.0 Mg ha-1 lime, and the application of lime + phosphogypsum (2.0 + 2.1 Mg ha-1, respectively). Since the experiment was established in 2002, the rates have been applied three times (2002, 2004, and 2010). Surface liming effectively increased water-stable aggregates > 2.0 mm at a depth of up to 0.2 m; however, the association with phosphogypsum was considered a good strategy to improve the macroaggregate stability in subsoil layers (0.20 to 0.40 m). Consequently, both soil amendments applied together increased the mean weight diameter (MWD) and geometric mean diameter (GMD) in all soil layers, with increases of up to 118 and 89%, respectively, according to the soil layer. The formation and stabilization of larger aggregates contributed to a higher accumulation of total organic carbon (TOC) on these structures. In addition to TOC, the MWD and aggregate stability index were positively correlated with Ca2+ and Mg2+ levels and base saturation. Consequently, the increase observed in the aggregate size class resulted in a better organization of soil particles, increasing the macroporosity and reducing the soil bulk density and penetration resistance. Therefore, adequate soil chemical management

Combination of biochar amendment and phytoremediation for hydrocarbon removal in petroleum-contaminated soil.