Disturbed Soil Columns Research Articles

Testing of leachability and persistence of sixteen pesticides in three agricultural soils of a semiarid Mediterranean region

Leaching, the movement of water and chemicals into deeper soil layers and groundwater is a subject of worldwide interest because a high percentage of drinking water is extracted from groundwater. The objective of this study was to evaluate the potential leaching and persistence of sixteen pesticides (one fungicide, three nematicides/insecticides, and twelve herbicides) for three Mediterranean agricultural soils with similar texture (clay loam) but different organic matter content (1.2-3.1%). Adsorption was studied in batch experiments and leaching was tested using disturbed soil columns (40 cm length × 4 cm i.d.). Degradation studies were carried out during 120 days under laboratory conditions. Mobility experiments showed that pesticides can be grouped according to their potential leaching. Thus, pesticides showing medium leachability were included in group 1 (referred as G1) while those with high leachability were termed as G2. The differences observed in the leachability can be attributed to the different organic carbon (OC) content in the soils (0.7-1.8%). Values of log KOC were higher in the order: soil C > soil B > soil A, which agrees with the OC content in each soil. The calculated half-lives ranged from 4.2 days for carbofuran in soil A to 330 days for prometon in soil C. As a general rule, when higher OC content in the soil the greater persistence of the pesticide was observed as a consequence of the increased adsorption. The first order kinetics model satisfactorily explains the disappearance of the studied pesticides in the soil.

Column leaching experiments on saline soils of different textures in Sistan plain

Salinization is the main characteristic of soils in arid and semi-arid regions which reduce the agricultural potential ofirrigated lands. Therefore, soil reclamation as well as determination of the leaching requirement for salt control is veryimportant for better plant growth. In this study, the effects of leaching on saline soils of Sistan region, southeast of Iranwere examined using unsaturated disturbed soil columns. The experiment was conducted on four texture types (loam,sandy clay loam, sandy loam and clay loam) and three replications. Soil samples were purred in polyvinyl chloride (PVC)cylinders and leaching procedures were conducted in 10 stages with up to 5 pore volumes. Effluent from each columnwas collected and evaluated in terms of Na+, K+, Ca2+, Mg2+ and EC. At the end of the study, soil columns were cut andtheir corresponding samples were analyzed for Na+, K+, Ca2+, Mg2+ and EC. The results of leaching experiments showedthat the water used in this study could reduce solute concentration and thus, this soil does not need any amendment. Formost soil textures, it was also observed that almost 85% of the salts were leached after the fifth stage of the leachingprocess. According to the results, ions entry into the effluent solution is fast in the coarse textured soils. So, the differencebetween the amounts of irrigation water needed to transport the salts and leach the saline soils can be attributed to thesoil texture. It seems that the main reason for these reactions is the cation exchange.

Modeling atrazine transport in soil columns with HYDRUS-1D

Both physical and chemical processes affect the fate and transport of herbicides. It is useful to simulate these processes with computer programs to predict solute movement. Simulations were run with HYDRUS-1D to identify the sorption and degradation parameters of atrazine through calibration from the breakthrough curves (BTCs). Data from undisturbed and disturbed soil column experiments were compared and analyzed using the dual-porosity model. The study results show that the values of dispersivity are slightly lower in disturbed columns, suggesting that the more heterogeneous the structure is, the higher the dispersivity. Sorption parameters also show slight variability, which is attributed to the differences in soil properties, experimental conditions and methods, or other ecological factors. For both of the columns, the degradation rates were similar. Potassium bromide was used as a conservative non-reactive tracer to characterize the water movement in columns. Atrazine BTCs exhibited significant tailing and asymmetry, indicating non-equilibrium sorption during solute transport. The dual-porosity model was verified to best fit the BTCs of the column experiments. Greater or lesser concentration of atrazine spreading to the bottom of the columns indicated risk of groundwater contamination. Overall, HYDRUS-1D successfully simulated the atrazine transport in soil columns.

Use of different organic wastes as strategy to mitigate the leaching potential of phenylurea herbicides through the soil.

In this study, the leaching of 14 substituted phenylurea herbicides (PUHs) through disturbed soil columns packed with three different soils was investigated in order to determine their potential for groundwater pollution. Simultaneously, a series of experiments were conducted to demonstrate the effect of four different organic wastes (composted sheep manure (CSM), composted pine bark (CPB), spent coffee grounds (SCG) and coir (CR)) on their mobility. All herbicides, except difenoxuron, showed medium/high leachability through the unamended soils. In general, addition of agro-industrial and composted organic wastes at a rate of 10% (w/w) increased the adsorption of PUHs and decreased their mobility in the soil, reducing their leaching. In all cases, the groundwater ubiquity score (GUS) index was calculated for each herbicide on the basis of its persistence (as t ½) and mobility (as K OC). The results obtained point to the interest in the use of agro-industrial and composted organic wastes in reducing the risk of groundwater pollution by pesticide drainage.

Assessment of agro-industrial and composted organic wastes for reducing the potential leaching of triazine herbicide residues through the soil

In this study, we examined the effect of four different organic wastes – composted sheep manure (CSM), spent coffee grounds (SCG), composted pine bark (CPB) and coir (CR) – on the sorption, persistence and mobility of eight symmetrical and two asymmetrical-triazine herbicides: atrazine, propazine, simazine, terbuthylazine (chlorotriazines), prometon (methoxytriazine), prometryn, simetryn, terbutryn (methylthiotriazines), metamitron and metribuzin (triazinones). The downward movement of herbicides was monitored using disturbed soil columns packed with a clay loam soil (Hipercalcic calcisol) under laboratory conditions. For unamended and amended soils, the groundwater ubiquity score (GUS) was calculated for each herbicide on the basis of its persistence (as t½) and mobility (as KOC). All herbicides showed medium/high leachability through the unamended soils. The addition of agro-industrial and composted organic wastes at a rate of 10% (w:w) strongly decreased the mobility of herbicides. Sorption coefficients normalized to the total soil organic carbon (KOC) increased in the amended soils. These results suggest that used organic wastes could be used to enhance the retention and reduce the mobility of the studied herbicides in soil.

Use of different organic wastes in reducing the potential leaching of propanil, isoxaben, cadusafos and pencycuron through the soil

In this study, we examined the effect of four different organic wastes (OW)—composted sheep manure (CSM), spent coffee grounds (SCG), composted pine bark (CPB) and coir (CR)—on the potential groundwater pollution of propanil and isoxaben (herbicides), cadusafos (insecticide) and pencycuron (fungicide) under laboratory conditions. For this purpose, leaching studies were conducted using disturbed soil columns filled with a clay loam soil (Hipercalcic calcisol). The addition of organic matter (OM) drastically reduced the movement of the studied pesticides. The results obtained point to the interest in the use of agro-industrial and composted OW in reducing the groundwater pollution by pesticide drainage.

Minimization of methabenzthiazuron residues in leaching water using amended soils and photocatalytic treatment with TiO2 and ZnO

In the present work, potential groundwater pollution by methabenzthiazuron (MTBU) and the effect of three different amendments (composted sheep manure, composted pine bark and spent coffee grounds) on its mobility were investigated under laboratory conditions. The efficiency of ZnO and TiO2 suspensions in the photocatalytic degradation of MTBU in leaching water was also investigated. The relative and cumulative breakthrough curves were obtained from disturbed soil columns. The presence and/or addition of organic matter drastically reduced the movement of the herbicide. On other hand, photocatalytic experiments showed that the addition of ZnO and TiO2 strongly enhances the degradation rate of this herbicide compared with the results of photolytic experiments under artificial light. ZnO appeared to be more effective in MTBU oxidation than TiO2. The results obtained point to the interest of using organic wastes and heterogeneous photocatalysis for reducing the pollution of groundwater by pesticide drainage.

Effects of soil structural properties on saturated hydraulic conductivity under different land-use types

Soil structure has important influences on edaphic conditions and environment, is often related to aggregate stability. The saturated hydraulic conductivity (Ks) is an important soil hydraulic property that affects water flow and transport of dissolved solutes. The objective of this study was to analyse the impact of water-stable aggregate stability on Ks under different land-use types. Using a range of aggregate stabilities in disturbed soil columns, Ks was measured and relationships between the mean weight diameter (MWD) of aggregates and Ks for three different conditions (three soil layers, four land use types, two water supply methods) were determined. Differences between soil aggregate characteristics and organic matter content among the land use types were significant. Using both both top and bottom water supply methods, MWD was related to Ks by a non-linear function (coefficient of determination >0.95), and land-use type and water supply method were significant factors. When undisturbed soil columns were investigated, the relationship between MWD and Ks was obscured by other soil environmental factors.

<b>The influence of organic matter from swine wastewater on the interaction and transport of alachlor in soil</b> - doi: 10.4025/actasciagron.v35i3.16374

This study evaluated the effects of total and dissolved organic matter produced from two swine wastewater treatment systems, a biodigester and a manure lagoon, on the adsorption, desorption, and leaching of alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) in soil. It was used the batch equilibrium method to test adsorption and desorption, and the results are presented in Freundlich isotherms. It also used disturbed soil columns to evaluate the miscible displacement of alachlor in soil treated with total and dissolved organic matter. This assay was used to monitor the concentration of alachlor in the leached material, the amount of total organic carbon, and the pH. The addition of swine wastewater promoted greater adsorption and desorption of alachlor compared with the control. The dissolved organic matter promoted less soil adsorption of alachlor compared with the total organic matter and also interacted with the alachlor and/or competed with the exchangeable cation sites in the soil, resulting in greater leaching. The total organic matter contributed to the emergence of new sorption sites in the soil column, and the solids present in the composition may have blocked pesticide passage, resulting in lower loss of alachlor due to leaching.

Zeolite Effects on Immobile Water Content and Mass Exchange Coefficient at Different Soil Textures

The concern for groundwater pollution by agrichemicals through solute movement within the soil is widespread. Zeolite is a type of soil amendment that is utilized to improve physical properties of soil and ameliorate polluted soil. The high negative charge of the zeolite and its open space structure allows adsorption and access of heavy metals and other cations and anions. The objectives of this research were (i) to determine the effects of different application rates of zeolite (0, 2, 4, and 8 g kg−1) on the immobile water content and mass exchange coefficient in a loam soil and then (ii) to determine the effects of optimum application rate of zeolite on the immobile water content and mass exchange coefficient of sandy loam and clay loam soils in saturated conditions by a mobile and immobile (MIM) model. In a disturbed soil column, a method was proposed for determination of MIM model parameters, that is, immobile water content (θim), mass exchange coefficient (α), and hydrodynamic dispersion coefficient (Dh). Breakthrough curves were obtained for different soil textures with different zeolite applications in three replicates, by miscible displacement of chloride (Cl−1) in disturbed soil column. Cl−1 breakthrough curves were evaluated in terms of the MIM model. The results showed that the pore water velocity calculated based on the total soil volumetric water content (θim+ θm) and real pore water velocity calculated based on the mobile water content (θm) increased in the loam soil with an increase in zeolite application rate, so that, between these different rates of zeolite application, the maximum value of pore water velocity and real pore water velocity occurred at zeolite application rates of 8.6 and 11.5 g kg−1, which are indicated as the optimum application rates. However, the comparison between different soils showed that the zeolite application rate of 8 g kg−1 could increase pore water velocity of sandy loam and loam soils by 31% more than that of clay loam soil. The immobile water content and mass exchange coefficient of loam soil were correlated with the zeolite application rate and reduced with an increase in the rate of applied zeolite. In a comparison between different soils at zeolite application rate of 8 g kg−1, the immobile water contents of the zeolite-treated soil decreased by 57%, 60%, and 39% on sandy loam, loam, and clay loam soils, respectively, compared with the untreated soil. Furthermore, zeolite application could reduce mass exchange coefficient by 9%, 43%, and 21% on sandy loam, loam, and clay loam soils, respectively. A positive linear relationship was found between θim and α. Zeolite application increased real pore water velocity of sandy loam soil by 39% and 46% compared with loam and clay loam soils, respectively. In other studies there was a decrease in ammonium and nitrate leaching due to the zeolite application, and therefore, an increase in real pore water velocity due to zeolite application in sandy loam soil, as compared with the loam and clay loam soils, may not show more rapid movement of solute and agrichemicals to the groundwater.

Assessment of the Leaching Potential of 12 Substituted Phenylurea Herbicides in Two Agricultural Soils under Laboratory Conditions

In this study, the potential groundwater pollution of 12 substituted phenylurea herbicides (chlorbromuron, chlorotoluron, diuron, fenuron, fluometuron, isoproturon, linuron, metobromuron, metoxuron, monolinuron, Monuron, and neburon) was investigated under laboratory conditions. For this purpose, leaching studies were conducted using disturbed soil columns filled with two different agricultural soils, one hypercalcic calcisol (HC) and the other endoleptic phaeozem (EP). In the case of the HC, all of the studied herbicides were found in leachates, while for the EP only, chlorbromuron, chlorotoluron, isoproturon, monolinuron, and, especially, fenuron were recovered. For both soils, the groundwater ubiquity score (GUS) index was calculated for each herbicide on the basis of its persistence (as t(1/2)) and mobility (as K(OC)). The half-lives obtained were markedly higher in the EP (217-518 days) than in the HC (71-178 days). As a consequence, higher values of GUS indexes were observed for EP. The ratio of the GUS between the EP and the HC was about 1.3.

Bioremediation of carbofuran contaminated soil under saturated condition: soil column study

Disturbed soil columns, 5.8cm in diameter and 25cm in length, were used as a basic model to simulate the movement of carbofuran in rice field soil under saturated conditions. Bioaugmentation using a specific carbofuran degrader, Burkholderia sp. PCL3, in free and immobilized cell forms and biostimulation using rice straw as organic amendment were applied with the aim of enhancing the degradation of carbofuran in soil and to prevent the movement of carbofuran along with the flow through. In the abiotic control and the treatment with only indigenous microorganisms, the mass recovery percentage of carbofuran in the effluent was 52.1 and 22.5%, respectively. The application of bioaugmentation or biostimulation significantly enhanced carbofuran degradation in soil and reduced the movement of carbofuran as indicated by a low mass recovery percentage of carbofuran in the effluent of 14.6-15.5%. A low efficiency of carbofuran removal was obtained from the soil column with bioaugmentation together with biostimulation treatments in which the mass recovery percentage of carbofuran in the effluent was in the range of 22.1-22.6%. Sorption of carbofuran to soil, rice straw and corncob, formation of carbofuran metabolite and colony forming unit (CFU) and pH variation with the time were also investigated during column operation.

Relação da velocidade de escoamento da solução e do comprimento da coluna de solo com os parâmetros de transporte de potássio em um latossolo e um neossolo

Devido à importância dos estudos de deslocamento de solutos em colunas de solo, para avaliar os riscos de poluição do solo e das águas subterrâneas, e à falta de padronização no comprimento da coluna de solo utilizada (L) e na velocidade de escoamento da solução aplicada (), realizou-se este trabalho com o objetivo de avaliar a relação de L e de com o coeficiente de dispersão-difusão (D), a dispersividade (λ) e o fator de retardamento (R) do K+ em um Latossolo Vermelho distrófico (LVd) e num Neossolo Quartzarênico órtico (RQo). Foram testados cinco comprimentos de colunas (0,10, 0,20, 0,30, 0,40 e 0,50 m) e quatro velocidades, sendo 0,62, 0,69, 0,75 e 0,81 m h-1 para o LVd e 0,37, 0,40, 0,44 e 0,48 m h-1 para o RQo. Aplicou-se uma solução deslocadora de 130 mg L-1 de K+ nas colunas montadas com o solo desestruturado e saturadas com uma solução de CaCl2 5 mmol L-1. Os parâmetros de transporte R e D foram obtidos utilizando-se o programa computacional Disp; a λ foi obtida pela equação D = Do + λ, sendo Do igual a 7,13 10-6 m² h-1 para o KCl. Houve relação do comprimento da coluna e da velocidade de escoamento da solução com os parâmetros de transporte do K+ tanto no LVd quanto no RQo. No LVd, o fator de retardamento aumentou com o aumento na velocidade de escoamento da solução. Em ambos os solos, o fator de retardamento diminuiu com o aumento no comprimento da coluna; o coeficiente de dispersão-difusão aumentou com o aumento na velocidade de escoamento da solução e com o aumento no comprimento da coluna de solo; e a dispersividade também aumentou com o aumento no comprimento da coluna.

Reduction of the movement and persistence of pesticides in soil through common agronomic practices

Laboratory and field studies were conducted in order to determine the leaching potential of eight pesticides commonly used during pepper cultivation by use of disturbed soil columns and field lysimeters, respectively. Two soils with different organic matter content (soils A and B) were used. Additionally, soil B was amended with compost (sheep manure). The tested compounds were cypermethrin, chlorpyrifos-methyl, bifenthrin, chlorpyrifos, cyfluthrin, endosulfan, malathion and tolclofos-methyl. In soil B (lower organic matter content), only endosulfan sulphate, malathion and tolclofos-methyl were found in leachates. For the soil A (higher organic matter content) and amended soil B, pesticide residues were not found in the leachates. In addition, this paper reports on the use of common agronomic practices (solarization and biosolarization) to enhance degradation of these pesticides from polluted soil A. The results showed that both solarization and biosolarization enhanced the degradation rates of endosulfan, bifenthrin and tolclofos-methyl compared with the control. Most of the studied pesticides showed similar behavior under solarization and biosolarization conditions. However, chlorpyrifos was degraded to a greater extent in the solarization than in biosolarization treatment. The results obtained point to the interest in the use of organic amendment in reducing the pollution of groundwater by pesticide drainage and in the use of solarization and biosolarization in reducing the persistence of pesticides in soil.

Effects of physicochemical soil properties of five agricultural soils on herbicide soil adsorption and leaching

Once pesticides reach the soil, there are several factors that affect their soil behavior. To identify the principal soil and herbicide properties that control their adsorption and leaching, a study of five Chilean agricultural and forest soils was performed. Simazine, diuron, terbuthylazine and MCPA were applied to the top of 45-cm tall by 12-cm diameter disturbed soil columns, filled with either an Andisol, Ultisol, Entisol or one of two Inceptisol soils. After herbicide applications, each lysimeter received 24 mm of simulated rain every 24 hours for five days. Once water percolation stopped, the lysimeters were divided into five sections and herbicide concentrations were quantified using High Pressure Liquid Chromatography. Relationships between soil physicochemical properties, herbicide sorption (adsorption and desorption) and herbicide leaching were determined. All herbicides exhibited the least depth reached from the Andisol soil (10 cm) and the highest from the Ultisol soil (45 cm). The principal soil property that affected herbicide adsorption was the soil organic carbon content, specifically the fulvic acid-humins fraction. Soil leaching was related to the inverse of soil adsorption (1/Kd), cation exchange capacity, humic substances content and herbicide pKa. These results suggest that it is possible to develop simple quantitative models to predict the soil-leaching properties of pesticides

Transport of dimethoate through a Mediterranean soil under flowing surfactant solutions and treated wastewater

Surfactants, which are emitted to soils mainly through wastewater disposal and also for remediation purposes, can alter pesticide sorption/desorption as well as the water flow through the soil. As a consequence, pesticide mobility may change and affect groundwater quality. Therefore, a deep insight into the coupled transport of pesticides and surfactants is necessary and helpful for contamination prevention and remediation. Dimethoate leaching was performed after flowing wastewater and surfactant solutions (Tween 80 and sodium dodecyl sulfate, SDS) through disturbed soil columns. To identify relevant parameters related to dimethoate mobility, breakthrough curves were fitted with convection dispersion (CDE) transport model. In all cases, the elution peaks showed a rapid release in the early tailing followed by a much slower release in the extended tailing with a retention factor close to 1, as corresponds to a weakly retained compound. CDE non-equilibrium parameters showed that, independently from the leaching solution employed, most of the pesticide was transported in the solution phase (convective transport). Infiltrated volume for wastewater was the highest (2× Tween and 5× SDS) for the same infiltration period, which increases the risk of early groundwater pollution. On the other hand, SDS decreased soil permeability providing a slight retention of dimethoate on soil, mainly in the lower column layer.

Use of farming and agro-industrial wastes as versatile barriers in reducing pesticide leaching through soil columns

Increased interest has been recently focused on assessing the influence of the addition of organic wastes related to movement of pesticides in soils of low organic matter (OM) content. This study reports the effect of two different amendments, animal manure (composted sheep manure) and agro-industrial waste (spent coffee grounds) on the mobility of 10 pesticides commonly used for pepper protection on a clay-loam soil (OM=0.22%). The tested compounds were azoxystrobin, cyprodinil, fludioxonil, hexaconazole, kresoxim-methyl, pyrimethanil, tebuconazole, and triadimenol (fungicides), pirimicarb (insecticide), and propyzamide (herbicide). Breakthrough curves were obtained from disturbed soil columns. Cumulative curves obtained from unamended soil show a leaching of all pesticides although in different proportions (12–65% of the total mass of compound applied), showing triadimenol and pirimicarb the higher leachability. Significant correlation (r=0.93, p<0.01) was found between the observed and bibliographical values of GUS index. The addition of the amendments used drastically reduced the movement of the studied pesticides. Only two pesticides were found in leachates from amended soils, pyrimethanil (<1%) for both, and pirimicarb (44%) in the soil amended with spent coffee grounds. A decrease in pesticide leaching was observed with the increase in dissolved organic matter (DOM) of leachates. The results obtained point to the interest in the use of organic wastes in reducing the pollution of groundwater by pesticide drainage.

Leaching potential of several insecticides and fungicides through disturbed clay-loam soil columns

A laboratory study was conducted in order to determine the leaching potential of five insecticides and six fungicides commonly used during pepper cultivation by use of disturbed soil columns. The tested compounds were pyridaben, pyriproxyfen, tebufenpyrad, buprofezin and pirimicarb (insecticides/acaricides) and azoxyxtrobin, kresoxim-methyl, hexaconazole, tebuconazole, triadimenol, and pyrimethanil (fungicides). For this purpose, 100 µg of each pesticide were added to columns (n = 5) filled with 150 g of a clay loam soil and leached with 600 mL of 0.01 M CaCl2 during 10 days. Finally, leachates and soil fractions were analysed for pesticide residues. For insecticides only pirimicarb was found in leachates (48% of the initial amount) while 55% was recovered from the soil layers. For the other studied insecticides, the percentage remaining in the top soil fraction was nearly the total amount added and therefore showing ‘non-leaching’ behaviour. In the case of fungicides 41% of triadimenol and 6% of pyrimethanil were found in leachates. The amount recovered in leachates for the other fungicides was lower than 2%, hexaconazole and tebuconazole exhibiting the higher retention on the upper layer of soil. Therefore, is extremely important to propose methods and conduct to avoid the potential adverse effect of pesticides behaving as ‘leacher’ compounds.

Advective–Dispersive Equation with Spatial Fractional Derivatives Evaluated with Tracer Transport Data

The classical model used to describe solute transport in soil is based on the advective–dispersive equation (ADE) in which an analog of Fick's law is used to model dispersion. The fractional ADE (FADE) has been proposed to address discrepancies between experimental solute concentrations and those predicted with the ADE. The order of the fractional derivative or Lévy exponent, α, characterizes the deviation of the FADE solutions from the ADE, which is a specific case of the FADE for α = 2. The objective of this work was to test the hypothesis that using the FADE with values of α other than 2 can provide more accurate simulations of solute transport in soils. We fitted the FADE to 47 published data sets on tracer breakthrough in disturbed and undisturbed soil columns. The FADE was solved numerically with a mass‐conserving boundary condition. While 19 breakthrough curves were best fitted with the ADE, the rest were fitted better using the FADE with α &lt; 2. The RMSEs of the FADE and ADE were close when the FADE α was &gt;1.5. In contrast, the FADE RMSEs were, on average, 1.5 times smaller than the ADE RMSE when the FADE was fitted with α &lt; 1.5. The value of α apparently reflected the structure of the void space available for flow and transport. Considered as a generalization of the classical ADE, the FADE can be a useful model if tails of the breakthrough curve are of special interest.

Effect of soil structure disturbance on erosion and phosphorus losses from Finnish clay soil

No-till (NT) has proved to be an effective method to reduce erosion and losses of particulate phosphorus (PP) from fields to watercourses. However, the accumulation of P in the uppermost soil layer and the increased leaching risk of dissolved reactive phosphorus (DRP) in surface runoff reduce the environmental benefits of NT. The objective of this study was to determine whether the concentration of DRP in percolates could be decreased by mixing surface soil (0–5 cm) and deeper soil layers (5–20 cm) and how this affects erosion. We also tested the impact of high ionic strength on erosion from undisturbed and disturbed soil columns. Soil samples were collected from conventionally tilled (CT) and non-tilled (for 5 years) plots from a clay field (Vertic Cambisol) at 0–2.5, 2.5–10 and 10–20 cm depths. Moreover, undisturbed and disturbed soil columns representing the same plots were saturated with water in the laboratory and allowed to drain. The physico-chemical properties of the percolates were analysed to unravel the impact of cultivation methods and disruption of the aggregate structure. To see the effect of high ionic strength on detachment of soil particles, the soil columns were leached with ammonium acetate solution. The low pH of NT surface soil had enhanced the sorption of P and easily-soluble P had accumulated in the uppermost soil layer. Surprisingly, this enrichment did not increase the DRP concentration in the percolates when water percolated through the 0–5 or 0–20 cm soil layers. Disruption of the aggregate structure increased the turbidity and concentrations of suspended solids and PP in the percolates. In the NT samples, this action increased the concentration of DRP relatively more than in the CT samples. When the disturbed soil columns were leached with a solution of high ionic strength, the turbidity of the eluates was almost as low as before the breakage. To prevent erosion and the leaching of PP and DRP, we have to ensure an even water infiltration by improving the soil structure and by avoiding the disruption of stabilized aggregates. Ploughing the surface layer of NT soil can be recommended only if erosion from the field can be kept under control.