The use of fungicides bears the risk of many undesirable outcomes that are manifested in, among other things, changes in the structure and activity of microorganisms. This study aimed at determining ...the effect of a Helicur 250 EW preparation, used to protect crops against fungal diseases, on the microbiological and biochemical activity of soil and on the development of Horderum vulgare L. The fungicide was sprayed on leaves of spring barley in the following doses (per active substance, i.e. tebuconazole, TEB): 0.046, 0.093, 0.139, 1.395, and 2.790 mg TEB plant−1. The following indices were analyzed in the study: index of microorganisms resistance (RS) to the effects of fungicide, microorganisms colony development index (CD), microorganisms ecophysiological diversity index (EP), genetic diversity of bacteria, enzymatic activity, and effect of the fungicide on spring barley development (IFH). The most susceptible to the effects of the fungicide turned out to be fungi. The metagenomic analysis demonstrated that the bacterial community differed in terms of structure and percentage contribution in the soil exposed to the fungicide from the control soil even at the Phylum level. However, Proteobacteria appeared to be the prevailing taxon in both soils. Bacillus arabhattai, B. soli, and B. simplex occurred exclusively in the control soil, whereas Ramlibacter tataounensis, Azospirillum palatum, and Kaistobacter terrae – exclusively in the soil contaminated with the fungicide. Helicur 250 EW suppressed activities of all soil enzymes except for arylsulfatase. In addition, it proved to be a strong inhibitor of spring barley growth and development.
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•Helicur 250 EW contributed to the disturbance of soil homeostasis.•The fungicide changed the genetic diversity of bacteria and enzymatic activity in soil.•Microorganisms, enzymes and spring barley can be used as a bioindicators.
This paper presents the main characteristics of Eutric Cambisols, their productivity potential expressed as land-rating, and their spatial distribution in Slovenia. Differences in soil properties ...were evaluated among the six predominant groups of Eutric Cambisols; classification was based on the parent material. In addition to individual characteristics affecting soil quality (texture, soil depth, amount of plant available water, pH, base saturation, cation exchange capacity), a comparison of land-rating values between the groups was also performed. We analysed 200 profiles excavated as part of the Slovenian Soil Mapping or other soil surveys conducted by the Center for Soil and Environmental Sciences, Biotechnical Faculty, University of Ljubljana. Our results show that Eutric Cambisols cover 15.5% of the area of Slovenia. Most Eutric Cambisols are on flysch (19.3%, 600 km²), followed by Eutric Cambisols on marl (12.7%, 398 km²). Eutric Cambisols on sandy gravel alluvial sediments, an important soil for crop production, cover 295 km² (9.4%). They have a favourable loamy texture and optimal pH. The flat terrain also contributes to this soil’s highest average weighted land-rating value (70 points). The average weighted land-rating value of all Eutric Cambisols is higher than the average weighted land-rating value of all agricultural and forest land in Slovenia, which is 36 points; this must be considered in spatial planning, as this type of land has a small share and above all, it must be protected from various degradations.
One of the methods for testing splash (the first phase of water erosion) may be an analysis of photos taken using so-called high-speed cameras. The aim of this study was to determine the ...reproducibility of measurements using a single drop splash of simulated precipitation. The height from which the drops fell resulted in a splash of 1.5 m. Tests were carried out using two types of soil: Eutric Cambisol (loamy silt) and Orthic Luvisol (sandy loam); three initial pressure heads were applied equal to 16 kPa, 3.1 kPa, and 0.1 kPa. Images for one, five, and 10 drops were recorded at a rate of 2000 frames per second. It was found that (i) the dispersion of soil caused by the striking of the 1st drop was significantly different from the splash impact caused by subsequent drops; (ii) with every drop, the splash phenomenon proceeded more reproducibly, that is, the number of particles of soil and/or water that splashed were increasingly close to each other; (iii) the number of particles that were detached during the splash were strongly correlated with its surface area; and (iv) the higher the water film was on the surface the smaller the width of the crown was.
This paper was oriented to characterise spatio-temporal variation of soil organic carbon (SOC) over a 30-year period and to explore its driving forces in East China. A comparative study was done of ...data obtained during 1980 and 2010 in Anhui Province. Spatio-temporal changes of SOC density and storage in the surface (0–30 cm) and 0–100 cm layers were analysed using geographic information system (GIS) spatial analysis techniques. Relationships between soil erosion, land use change, agricultural management, and changes in SOC are discussed. Results show: (1) over 30 years, the average SOC density decreased by 0.59 kg C m−2 in the surface layer and 1.63 kg C m−2 in 0–100 cm layer. The average SOC density increased in Calcaric Cambisols and Haplic Fluvisols, and decreased in other soil types.The average SOC density in upland increased but decreased as a result of other land use practices. (2) SOC density in the surface layer increased to the north but decreased to the south in Anhui. SOC density in the 0–100 cm layer increased in the central area and decreased to the south. About 59% of all soil increased in SOC density. (3) SOC storage decreased by 117.91 Tg C in the surface layer and decreased by 237.65 Tg C in the 0–100 cm layer. The SOC storage increased mainly in the northern and central areas. (4) Severe soil erosion was a main reason for the large reduction in SOC storage in western and southern Anhui. Cultivated land use that changed to paddy field from upland improved SOC more than changes to other land use types. SOC storage change in farmland was significantly and positively related to organic matter content in crop roots.
•SOC storage increased in 0–30 and 0–100 cm layer of farmland in the past 30 years.•The relative change in SOC was negatively correlated with its original content.•Soil erosion was a main reason of large reduction in SOC in mountain areas.•Land use changed into farmland improved SOC storage.•SOC change was positively related to organic matter content in crop roots.
Long-term series of observations over the spring water balance elements on fields with hydrologically contrasting agricultural backgrounds―a loose soil after fall moldboard plowing and a plowland ...compacted by 12–16% compared to the former soil (perennial grasses, winter crops, stubble)―have been analyzed. The values of surface runoff and water infiltration into the soil in the steppe and forest-steppe zones of European Russia have been calculated for the spring (flooding) period and the entire cold season. The hydrological role of fall plowing has been shown, and water balance elements for the current (1981–2016) and preceding (1957–1980) periods have been compared. A significant decrease in runoff and an increase of water reserve in the soil have been revealed on all plowland types. Consequences of changes in the spring water balance on plowland have been analyzed.
Digital medium-scale (1 : 100 000) soil map of the Southern Coast from the Aia Cape on the west to the town of Feodosiya on the east was compiled on the basis of field data obtained by the authors. ...This map contains actual information on the soil cover of natural, humanly transformed landscapes, and urbanized territories. The map was created using GIS and remote sensing methods (multispectral Landsat images were applied). The legend to the map was based on the
Classification and Diagnostic System of Russian Soils
(2004). The map comprises 1053 polygons and 34 soil units, which are arranged in four groups: natural soils, soils of terraced slopes, agricultural soils, and soils of urbanized territories. There is also information about rock outcrops, soil erosion intensity, and share of natural soils in the areas of human-modified soils. The analysis of the map demonstrates that natural soils occupy 63% of the area. The main natural soils are Dystric Cambisols (they compose approximately 35% of all natural soils) and Eutric Cambisols (about 23%). Among human-modified soils, soils of urbanized areas make up about 15%; agricultural soils, 12%; and soils of terraced slopes (Escalic qualifier in the WRB) under forest plantations, 10%. The latter soils are widespread and may be named “Postturbozems”; this term is absent in the
Classification and Diagnostic System of Russian Soils
(2004). The new digital soil map reflects the features of the present-day soil cover of the Southern Coast of Crimea and may be used for agricultural and forest management purposes, as well as for geographical, pedological, and ecological studies.
The physicochemical properties of soil and the unsaturated zone can have a large influence on the infiltration of precipitation into an aquifer. Soil permeability presents soil property that can be ...very variable. The main objectives of this study were to estimate differences in soil permeability in two dominant types of soils—Fluvisols and Eutric Cambisols—in the area of the Zagreb aquifer and determine the relationship between the physicochemical properties and the permeability of the analyzed soils. For this purpose, the particle size distribution, soil water retention curves (SWRCs), hydraulic parameters, and chemical properties of soils (i.e., electrical conductivity (EC), pH, carbonate content, cation exchange capacity (CEC), and total concentration of zinc (Zn)) from six soil profiles were observed. In general, the results show that Fluvisols have a smaller amount of clay and a higher amount of sand. Furthermore, particle size distribution indicates that Eutric Cambisols have smaller permeability and a slightly higher capacity for retention. In Eutric Cambisols, the percentages of clay, silt, and sand generally do not change with depth. On average, Fluvisols and Eutric Cambisols become impermeable when they reach different values of water content and effective saturation. All results suggest that Fluvisols generally have to desaturate more than Eutric Cambisols to become impermeable. The proportions of sand and Ks increases through the depth of all analyzed soils, while CEC, EC, and Zn decrease. The total Zn generally decrease with depth, which can be attributed to the aerodeposition in the surface horizons of the analyzed soils and their higher availability for binding/sorption elements. Generally, it can be seen that most Zn concentrations increase until 80 cm in depth, after which they decrease. This result indicates that, in these specific locations, the groundwater body is not under the influence of a potentially toxic metal, in this case Zn. Statistical analysis shows a strong correlation between Zn concentrations and some soil properties, such as soil texture and CEC. This may point to the prevalence of Zn retention. Furthermore, statistical results show that silt has a higher influence on the permeability of Eutric Cambisols than Fluvisols.
The humus status and CO
2
production have been assessed in soils of natural and anthropogenic landscapes in southern regions of the Far East with different types of redox conditions. A higher ...production of CO
2
is typical of burozems and soddy-eluvial-metamorphic soils with oxidative and contrast redox conditions. These are soils with medium or high humus content, high potential humification capacity, and medium enrichment with catalase. A decrease in the content of humus in the plow horizons of soils in agrogenic landscapes is revealed compared to their natural analogues. The studied soils mainly have humus of the fulvate–humate type. The fractions strongly bound to the mineral soil component prevail in humic acids. In waterlogged mucky-humus gley soils, the anaerobic conditions hamper the biological activity and transformation of organic matter, which favors its accumulation. A low production of CO
2
is observed in soils with reducing conditions. To determine the differences between the CO
2
emission parameters in soils of agrogenic and natural landscapes, monitoring studies should be extended.
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