scholarly journals Chlortoluron behavior in five different soil types

2011 ◽  
Vol 51 (No, 7) ◽  
pp. 304-309 ◽  
Author(s):  
M. Kočárek ◽  
R. Kodešová ◽  
J. Kozák ◽  
O. Drábek ◽  
O. Vacek
Keyword(s):  
Soil Profile ◽  
Preferential Flow ◽  
Soil Surface ◽  
Climatic Conditions ◽  
Soil Types ◽  
Flow Profile ◽  
Soil Database ◽  
Herbicide Transport ◽  
Subsurface Layers ◽  
High Concentrations

Chlortoluron transport was studied in five different soil types and under varying climatic conditions. The chlortoluron mobility in the monitored soils increases as follows: Albic Luvisol = Haplic Luvisol < Haplic Cambisol < Haplic Stagnosol < Greyic Phaozem. Significantly high concentrations in the top layer of Haplic Stagnosol were observed due to the high presence of coarse gravel (30–40%) and flow profile reduction up to 60%. The content of remaining chlortoluron in the soil profile corresponds to the herbicide mobility. The percentages of remaining chlortoluron were 46.1% in Albic Luvisol, 54.6% in Haplic Luvisol, 65.0% in Haplic Cambisol, 69.6% in Haplic Stagnosol and 102.9% in Greyic Phaozem. The highest herbicide degradations were at the locations with lower observed mobility and herbicide present mainly in the top layer. Occurrence of the remaining chlortoluron percentage in Greyic Phaozem higher than 100% was caused mainly by the herbicide transport through the preferential paths and restricted degradation in subsurface layers. Variability of chlortoluron distributions in the soil profiles observed at the three positions of the same location occurred due to the heterogeneity of the soil profile and an uneven distribution of chlortoluron on the soil surface. The BPS mathematical model (Kozák and Vacek 1996) connected with the soil database (Kozák et al. 1996) was used to simulate chlortoluron transport. The simulated chlortoluron concentrations follow approximately the measured data except for Greyic Phaozem, where a preferential flow highly influenced solution transport. The BPS model with the soil database can be used for estimation of the chlortoluron transport.

Contamination of soil with fluoride by long-term application of superphosphates to pastures and risk to grazing animals

Soil Research ◽  
2001 ◽  
Vol 39 (3) ◽  
pp. 627 ◽  
Author(s):  
M. J. McLaughlin ◽  
D. P. Stevens ◽  
D. G. Keerthisinghe ◽  
J. W. D. Cayley ◽  
A. M. Ridley
Keyword(s):  
Soil Profile ◽  
Soluble Fraction ◽  
Soil Surface ◽  
High Reactivity ◽  
Soil Ingestion ◽  
High Concentrations

Fluoride (F) is an impurity in phosphatic fertilisers and significant amounts of F will be added to soils with long-term application of phosphatic fertiliser to soil. There is a risk that F concentrations in soil may increase to levels toxic to plants or grazing animals. If F added to soil remains in the upper soil profile, due to high reactivity with soil, grazing animals could increase their intake of F through inadvertent ingestion of F-enriched soil. This study determined the distribution of F in the soil profile of medium (>8 years) and long-term permanent pastures (>50 years) where F had been applied as an impurity in phosphatic fertiliser, and assessed the potential bioavailability of fertiliser F in soil. Long-term application of superphosphate was linked to increased concentrations of the more soluble fraction of F in soil. The more soluble F fraction in the soil surface led to increased F concentrations in herbage (from 11 to 22 mg F/kg). Fluoride concentrations in herbage were not high enough to be toxic to plants or grazing animals. Fluoride applied as an impurity in phosphatic fertiliser was generally found to accumulate in the upper soil profile (0–6 cm depth). Such increases could also increase F ingestion by ruminants through incidental soil ingestion while grazing. The risk of fluorosis to grazing animals is low at present, but with continued application of fertiliser to soil containing high concentrations of F, and depending on the bioavailability of fertiliser-derived F in soil, we estimate that fluorosis may become an issue in the next 25–50 years in highly fertilised pasture soils.

scholarly journals Single and dual-permeability models of chlorotoluron transport in the soil profile

2011 ◽  
Vol 51 (No, 7) ◽  
pp. 310-315 ◽  
Author(s):  
R. Kodešová ◽  
J. Kozák ◽  
J. Šimůnek ◽  
O. Vacek
Keyword(s):  
Solute Transport ◽  
Soil Profile ◽  
Hydraulic Properties ◽  
Preferential Flow ◽  
Water Movement ◽  
Application Rate ◽  
Transport Parameters ◽  
Soil Hydraulic Properties ◽  
Permeability Model ◽  
Herbicide Transport

This study presents the transport of chlorotoluron in the soil profile under field conditions. The herbicide Syncuran was applied on a plot (4 m˛) using an application rate of 2.5 kg/ha of active ingredient. Soil samples were taken after 119 days to study the residual chlorotoluron distribution in the soil profile. The single and dual-permeability models in HYDRUS-1D (Šimůnek et al. 2003) were used to simulate water movement and herbicide transport in the soil profile. Soil hydraulic properties and their variability were previously studied by Kutílek et al. (1989). The solute transport parameters, such as the adsorption isotherm and the degradation rate, were determined in the laboratory. Since the solute transport in the field was probably affected by preferential flow, the chlorotoluron distribution in the soil profile calculated using the single-permeability model had a different character than observed chlorotoluron concentrations. The chlorotoluron distribution within depth calculated using the dual-permeability model was closer to the observed behavior of chlorotoluron. While the herbicide did not reach a depth of 8 cm for the single-porosity system, in the case of the dual-permeability model the solute moved to the depth of 60 cm. The dual-permeability model significantly improved correspondence between calculated and observed herbicide concentrations.

Problems and practical experiences during refilling of the Kerspe-Talsperre under unfavourable climatic conditions

1998 ◽  
Vol 37 (2) ◽  
pp. 145-152 ◽  
Author(s):  
A. E. Nienhüser ◽  
P. Braches
Keyword(s):  
Water Quality ◽  
Early Summer ◽  
Climatic Conditions ◽  
Oxygen Deficit ◽  
Light Limitation ◽  
Raw Water ◽  
Artificial Mixing ◽  
Poor Water Quality ◽  
High Concentrations ◽  
Practical Experiences

Refilling of the Kerspe-Talsperre reservoir after restoration of the dam caused severe problems in water quality and supply due to a long-lasting ice-cover period and minimal precipitation. Unusually short spring overturn, high algal mass in spring and certainly the overflooding of the sediment, which had not been removed, caused a tremendous oxygen deficit in early summer. The whole hypolimnion turned anoxic and even in the metalimnion oxygen declined to a minimum. Manganese and iron reached high concentrations. Despite the poor water quality, raw water was urgently needed for the water supply and was pumped from the epilimnion during the clear water phase and in July when algal biomass was low. In the middle of August holomixis was induced artificially in order to improve water quality. The decline in algal production during and after artificial mixing was probably caused by light limitation of the algae.

Interactions of surface drying and subsurface nutrients affecting plant growth on acidic soil profiles from an old pasture

1986 ◽  
Vol 26 (6) ◽  
pp. 681 ◽  
Author(s):  
A Pinkerton ◽  
JR Simpson
Keyword(s):  
Subsurface Layer ◽  
Acid Soils ◽  
Subterranean Clover ◽  
Soil Surface ◽  
Soil Profiles ◽  
Poor Growth ◽  
South Wales ◽  
Reconstituted Soil ◽  
Subsurface Layers ◽  
Surface Drying

Previous studies on soils from old pastures in southern New South Wales have demonstrated that nutrients have accumulated at the soil surface, but that the 40-100-mm depth layer in many profiles has become strongly acidic (e.g. pH 4.7), and high in extractable aluminium. Poor growth of subterranean clover has occurred on such soils during dry periods and may be associated with poor root growth in the acidic, nutrient-poor subsurface layers. Possible nutritional causes of these observations were investigated using reconstituted soil profiles. The root and shoot growth of subterranean clover, wheat, oats and lucerne were compared in unamended profiles and in profiles amended by applying nutrients or calcium carbonate (lime) to correct the more obvious deficiencies of the subsurface layers. Subterranean clover grew well as long as the surface soil remained moist, so that plants could utilise the nutrients potentially available within it. When the surface (0-40 mm) was allowed to dry but the subsurface layers remained moist, growth was poor unless phosphate was applied to the moist layer. Subsurface application of lime alone was ineffective. Nitrogen application increased clover growth in the presence of added phosphate or surface moisture, but nitrogen alone did little to alleviate the effects of surface drought. Wheat, and to a lesser extent oats, responded to subsurface lime when the surface was moist, and both responded to subsurface phosphate when the surface was dry. Lucerne responded to subsurface phosphate similarly to subterranean clover but the response was more than doubled in the presence of additional borate and lime. Lime without borate was not effective. When the surface was maintained moist, liming both the surface (0-40 mm) and subsurface layers improved the response over liming the subsurface layer only. The results suggest that declining fertility and productivity in old pastures developed on acid soils may not be rectified by liming alone, but that cultivation, ripping or drilling of phosphate, and in some cases addition of borate, may be required to improve the penetration of nutrients, particularly phosphorus, to greater depth.

scholarly journals Applicability of laser diffraction analyses in soil physics practice

2016 ◽  
Vol 5 (1-2) ◽  
pp. 32-37
Author(s):  
András Makó ◽  
József Szabó ◽  
Zsófia Bakacsi ◽  
Sándor Koós ◽  
Gabriella Hauk ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Laser Diffraction ◽  
Soil Samples ◽  
Soil Types ◽  
Diffraction Measurement ◽  
Boundary Values ◽  
Soil Physics ◽  
Soil Database ◽  
First Results

In this research we present the first results how can be used laser diffraction measurement in soil physics practice. The main goals are understanding differences of particle size distribution (PSD) measurments, developing converting methods of PSD data of different determinations. In order to realization of this survey a representative soil database of Hungarian soil types was built up. We compared PSDs of 157 soil samples measured with sieve-pipette method (SPM) and laser diffractometer technique (Malvern Mastersizer 2000) (LDM). Soil textural classes were also determined using the USDA texture triangle. We used the clay/silt fraction boundary values (clay < 0.0066 mm; silt: 0.0066 - 0.05 mm) introduced for the LDM data in order to take them comparable to PSD data determined by the SPM: We got higher similarities of clay and silt fractions of the modified size boundary values. For the used dataset correspondence of texture classes derived from SPM and LDM PSD data, however is not higher than 60%.

scholarly journals Assessment of vadose zone sampling methods for detection of preferential herbicide transport

2009 ◽  
Vol 6 (6) ◽  
pp. 7247-7285 ◽  
Author(s):  
N. P. Peranginangin ◽  
B. K. Richards ◽  
T. S. Steenhuis
Keyword(s):  
Vadose Zone ◽  
Preferential Flow ◽  
Sampling Methods ◽  
Sandy Loam ◽  
Silty Clay ◽  
Water Sampling ◽  
Herbicide Transport ◽  
Flow Mechanisms ◽  
Ceramic Cups ◽  
Zone Sampling

Abstract. Accurate soil water sampling is needed for monitoring of pesticide leaching through the vadose zone, especially in soils with significant preferential flowpaths. We assessed the effectiveness of wick and gravity pan lysimeters as well as ceramic cups (installed 45–60 cm deep) in strongly-structured silty clay loam (Hudson series) and weakly-structured fine sandy loam (Arkport series) soils. Simulated rainfall (10–14 cm in 4 d, approximately equal to a 10-yr, 24 h storm) was applied following concurrent application of agronomic rates (0.2 g m−2) of atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and 2,4-D (2,4-dichloro-phenoxy-acetic acid) immediately following application of a chloride tracer (22–44 g m−2). Preferential flow mechanisms were observed in both soils, with herbicide and tracer mobility greater than would be predicted by uniform flow. Preferential flow was more dominant in the Hudson soil, with earlier breakthroughs observed. Mean wick and gravity pan sampler percolate concentrations at 60 cm depth ranged from 96 to 223 μg L−1 for atrazine and 54 to 78 μg L−1 for 2,4-D at the Hudson site, and from 7 to 22 μg L−1 for atrazine and 0.5 to 2.8 μg L−1 for 2,4-D at the Arkport site. Gravity and wick pan lysimeters had comparably good collection efficiencies at elevated soil moisture levels, whereas wick pan samplers performed better at lower moisture contents. Cup samplers performed poorly with wide variations in collections and solute concentrations.

scholarly journals Spreading of chemical substance after its accidental spillage onto the soil surface under unsaturated conditions and variable porosity

2019 ◽  
pp. 41-44
Author(s):  
Olena Kozhushko ◽  
Petro Martyniuk
Keyword(s):  
Mathematical Model ◽  
Soil Moisture ◽  
Soil Profile ◽  
Moisture Transport ◽  
Soil Surface ◽  
Chemical Substance ◽  
High Concentration ◽  
Solute Transfer ◽  
Variable Porosity ◽  
The One

In this paper we study a mathematical model of soil moisture transport with variable porosity. The problem is set for the case of highly concentrated solute spilled onto soil surface. We investigate the way solute transfer, adsorption of contaminant by soil particles and variable porosity influence infiltration of solute into the soil profile. For that purpose, two models are used: a classical one and the one with consideration of mentioned factors. By comparing the results of both models, we established that high concentration of solute causes moisture transport to transpire more slowly, and the pollutant to remain on the soil surface for longer time. Numerical results indicate that porosity can vary considerably under the conditions of intensive contamination with salts.

scholarly journals Water repellency of clay, sand and organic soils in Finland

2008 ◽  
Vol 16 (3) ◽  
pp. 267 ◽  
Author(s):  
K. RASA ◽  
R. HORN ◽  
M. RÄTY
Keyword(s):  
Preferential Flow ◽  
Management Practice ◽  
Soil Surface ◽  
Water Repellency ◽  
Organic Soil ◽  
Water Infiltration ◽  
Organic Soils ◽  
Water Repellent ◽  
Moisture Regime ◽  
Wetting Process

Water repellency (WR) delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95) at the time of sampling. WR increased as follows: sand (R = 1.8-5.0) < clay (R = 2.4-10.3) < organic (R = 7.9-undefined). At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr.), where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

scholarly journals Influence of licopine content in tomatoes on taste qualities of canned goods

2020 ◽  
Vol 62 (5) ◽  
pp. 116-122
Author(s):  
Saida S. Saidova ◽  
Keyword(s):  
Antioxidant Properties ◽  
Food Products ◽  
Climatic Conditions ◽  
Raw Material ◽  
Technical Documentation ◽  
Tomato Fruits ◽  
Duration Of Storage ◽  
Tomato Products ◽  
High Concentrations ◽  
The Impact

The article provides a review of world data on the characteristics of the chemical composition of tomato fruits and the impact on their quality of the soil and climatic conditions of cultivation, varietal characteristics and maturity. It is noted that the current regulatory and technical documentation in the Russian Federation does not provide for the determination of functional substances. It has been shown that tomato fruits are a promising plant-growing raw material for the production of functional food products and directions for obtaining lycopene-containing products, canned foods, in particular, from tomato fruits, have been determined. The types of canned food and tomato products containing the highest concentrations of lycopene have been established. The regularity of increasing the concentrations of lycopene in tomato products with various methods of heat treatment is substantiated. The irreplaceable physiological significance of lycopene for the human body is proved, due to its antioxidant properties and the lack of the possibility of its synthesis. The biochemical nature of lycopene as a carotenoid and pigment is analyzed. The progressive foreign technologies of tomato processing have been studied, allowing to reduce the economic costs of production, increase the duration of storage of products containing extremely high concentrations of lycopene. The necessity of developing domestic food products of physiological importance, available for consumption in baby and diet food, is substantiated. It is proved that the Republic of Dagestan has a high climatic and resource potential for growing hybrid varieties of tomatoes containing high concentrations of lycopene and the mass fraction of dry matter necessary for the rational production of canned tomatoes.

scholarly journals CHEMICAL AND BIOLOGICAL INDICATORS FOR EVALUATION OF ARCTIC SOIL DEGRADATION AND ITS POTENTIAL TO REMEDIATION

2021 ◽  
Vol 29 (1) ◽  
pp. 33-39
Author(s):  
Tatiana S. Smirnova ◽  
Elena A. Mazlova ◽  
Olga A. Kulikova ◽  
Ilya M. Ostrovkin ◽  
Adam M. Gonopolsky ◽  
...  
Keyword(s):  
Biological Indicators ◽  
Climatic Conditions ◽  
Chloride Ions ◽  
The Arctic ◽  
Environmental Damage ◽  
Arctic Zone ◽  
Arctic Soils ◽  
Arctic Soil ◽  
Restoration Ability ◽  
High Concentrations

In recent years, significant efforts have been made to accelerate the economic development of the Arctic zone, leading to intense environmental pollution of this region, accompanied by the significant impact of accumulated environmental damage in the region. The solution to these problems is difficult due to the remoteness of these areas and severe climatic conditions. Therefore, it is important to evaluate the potential for restoration of arctic soils. For this purpose, various indicators are used, including biological ones. In the analyzed arctic soil samples, high concentrations of petroleum hydrocarbons (up to 47,000 mg/kg) and chloride-ions (0.10–0.14 wt %) were established. Microbioassay demonstrated a presence of hydrocarbon-oxidizing microorganisms: Penicillium, Azotobacter chroococcum, Bacillus subtilis, Pseudomonas oleovorans. A low enzymatic activity and specific Arctic climate point out a low self-restoration ability of the soil, demonstrated the need for its remediation. The microbioassay with microbial strains identification and soil remediation methods suitable for the Arctic zone were recommended.

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