Genome Sequence of the Thermophilic Soil Bacterium Ureibacillus terrenus ATCC BAA-384 T

Ureibacillus terrenus TH9A T (=ATCC BAA-384 T ) was isolated from uncultivated soil in Italy in 1995. We present a draft genome sequence for the type strain, with a predicted genome length of 2,936,851 bp, containing 2,766 protein-coding genes, 82 RNA genes, and 5 CRISPR arrays, with a G+C content of 42.5%.

Impact of a bacterial consortium on the soil bacterial community structure and maize (Zea mays L.) cultivation

Microorganisms are often applied as biofertilizer to crops to stimulate plant growth, increase yields and reduce inorganic N application. The survival and proliferation of these allochthonous microorganisms in soil is a necessary requisite for them to promote plant growth. We applied a sterilized or unsterilized not commercialized bacterial consortium mixed with cow manure leachate used by a farmer as biofertilizer to maize (Zea mays L.) in a greenhouse experiment, while maize development and the bacterial community structure was determined just before the biofertilizer was applied a first time (day 44), after three applications (day 89) and after six application at the end of the experiment (day 130). Application of sterilized or unsterilized biofertilizer with pH 4.3 and 864 mg NH4+-N kg−1 had no significant effect on maize growth. The application of the biofertilizer dominated by Lactobacillus (relative abundance 11.90%) or the sterilized biofertilizer changed the relative abundance of a limited number of bacterial groups, i.e. Delftia, Halomonas, Lactobacillus and Stenotrophomonas, without altering significantly the bacterial community structure. Cultivation of maize, however, affected significantly the bacterial community structure, which showed large significant variations over time in the cultivated and uncultivated soil. It was concluded that the bacteria applied as a biofertilizer had only a limited effect on the relative abundance of these groups in uncultivated or soil cultivated with maize.

Radioactivity of soil in Croatia II: 137Cs, 40K, and absorbed dose rate

We took samples of uncultivated soil from the surface layer (0–10 cm) at 138 sites from all over Croatia and measured their radionuclide activity concentrations with high-resolution gamma-ray spectrometry. This second part of our report brings the results on 40K and 137Cs to complement those on the 232Th and 238U decay chains addressed in the first part. Together they give the most complete picture of radioactivity of Croatian soil so far. Activity concentrations of 40K were the highest in the Pannonian region, and there was an opposite trend for 137Cs. We found that the concentrations of 137Cs tended to increase with altitude, annual precipitation, and vegetation density. The concentration ratio of 137Cs and K in soil, which indicates the potential for 137Cs entering food chains via uptake by plants, was the lowest in agriculturally important areas in the east of the Pannonian region. In addition, we used the obtained results on activity concentrations to calculate the related absorbed dose rate as a measure of external exposure to ionising radiation from soil. The sum of the absorbed dose rates for naturally occurring radionuclides and 137Cs showed that external exposure was generally the highest in the Dinaric region and Istrian Peninsula.

Radioactivity of soil in Croatia I: naturally occurring decay chains

The assessment of environmental radioactivity much relies on radionuclide content in soil. This stems from the significant contribution of soil to both external and internal exposure to ionising radiation via direct emission of gamma radiation and soil-to-plant radionuclide transfer, respectively. This motivated us to carry out a systematic research on the radioactivity of soil in Croatia to obtain relevant data that can be used as a basis for understanding the related effects of geomorphological, biogeographical, and climatological properties of the environment. We collected samples of the surface layer of uncultivated soil (0–10 cm) at 138 sites from all over the country and measured them for radionuclide activity concentrations by means of high-resolution gamma-ray spectrometry. This resulted in radioactivity maps containing data on activity concentrations of representative radionuclides in the environment. In this paper, which is the first in our two-part presentation, we focus on the naturally occurring 232Th and 238U decay chains and their correlations with the diversity of Croatian regions. For both of the chains, activity concentrations were the highest in the Dinaric region, the lowest in the Pannonian region, and intermediate in the Adriatic region. Relatively high concentrations of 226Ra in the soil of the Dinaric region implied a possibility of an enhanced emanation of its progeny 222Rn into the air. Activity concentrations of 210Pb were additionally elevated in areas with dense vegetation, most probably due to an atmospheric deposition of airborne 210Pb onto the surface of plants and their eventual decomposition on the ground.

A Novel Report on Killer Yeast Strains Identification Methods

This study was conducted to isolate and identify killer yeasts from soil samples that collected from different locations in Basrah and Dhi-Qar provinces. Seventy-five soil samples were collected from different areas, including sandy, arable, surface sediment and uncultivated soil, using dilution methods to cultivate a serial dilution of each soil sample. The results showed that a 112 isolates were identified biochemically using VITEK system and molecularly using internal transcribed spacer (ITS1- 5.8S-ITS2) marker. The molecular identification provided fast and precise identification results for the 112 isolates, whereas the VITEK test resulted low identification efficiency (8.2% were accurate and 91.8 % were not). The Diazonium blue B salts produced a good colour reaction in distinguishing between ascomycetes and basidiomycetes. The PCR was more accurate in identification of killer yeasts compared to the VITEK system.

Evaluation of the Efficiency of Soil with Deep Chiseling

The paper presents the evaluation of effectiveness of deep chiseling with the help of analytical methods. General objective of the work is to develop the method for describing theoretical interaction of operating parts of machines and tools with soil during main chiseling in the form of a stochastic process of successive hits of the operating part with a solid medium. The destruction of monoliths (uncultivated) soil during its cultivation was considered as a process of formation and subsequent evolution of dynamic cracks, the nature and amount of which, in a particular soil volume, is determined by the amount of energy absorbed by operating parts and the actual properties of cultivated soil. It should be taken into consideration that the spread of cracks during chiseling occurs by the lowest strength of connections between certain structural units, in fact organic inclusions, soil pores, moisture inclusions and other similar elements are the largest centers of formation, concentration and further development of cracks during cultivation. Interaction of operating parts of machines and tools with soil is most expedient to carry out modeling work in a thickness of the environment of a dihedral wedge taking into account mechanical structure of soil. It is established that the number of cracks and the size and number of lumps after cultivation are linearly dependent, which means that to qualitatively study the change in physical state, during chiseling with operating parts and tools, it is enough to study the process and evolution of cracking. As a result of the work performed, it is proved that the degree of soil grinding during its chiseling can be assessed by probability, and the quality of tools, that is the percentage of total mass of cultivated soil particles with the size not exceeding 50 mm. When modeling chiseling, the grinding process can be considered in the form of interaction of a dihedral wedge with a solid structured layer of soil with specified properties. The interaction of the chiseling operating part with the soil is accompanied by deformation of soil environment, increased stresses and cracks, which ultimately determine the shape and size of the crushed units. We believe that the number and nature of cracks that occur during tillage are in direct proportion to the size of the obtained units upon completion.

ENVIRONMENT-IMPROVING VALUE OF CLOVER IN THE CONDITIONS OF MINIMIZED TILLAGE OF SOD-PODZOLIC SOIL

In 2017–2019, the authors studied the influence of the meadow clover on the density, soil structure and biotic activity of sod-podzolic medium loamy lightly-eroded soil under plowing and minimal tillage in a stationary field experiment in the fourth rotation in the conditions of the Udmurt Republic. During the period of clover growth with minimal tillage, the topsoil density was reduced to the optimal parameters for cereal crops (1.29 g/cm3) and overcompaction of the uncultivated soil layer (1.59 g/cm3). Under these conditions, the clover formed a reliable increase in the yield of green mass of 8.9 t/ha relative to the yield obtained during plowing. The structural condition of the soil was described as good. A year later after the application of clover green mass, an aggregate analysis showed an improvement in the structure of the plough layer. The content of the lumpy fraction by plowing decreased by 6.0% in the 0–10 cm layer and 3.0% in the 10–20 cm layer, with minimal tillage of 7.6 and 16.0%, respectively. This made a positive effect on the biotic soil activity. Also, the decomposition level of cotton cloths was in a close positive relationship with the accumulation of small mesoaggregates of 0.5–1 mm in size (in topsoil r = 0.83, in the lower layer r = 0.80). An increase in the fine structure content of 0.25–0.5 and 0.5–1 mm was observed in both versions of soil tillage. As a result, the plow layer acquired an excellent structural condition. The barley of the 2019 yield on clover manure formed 3.70 t/ha of grain during plowing and 3.82 t/ha under the minimum tillage. The obtained results indicate the formation of optimal growing conditions for grain crops with minimal tillage of sodpodzolic medium loamy lightly-eroded soil of the Udmurt Republic due to the environment-improving properties of clover with the application of its green mass for green manure production.

Changes in Olive Urban Forests Infected by Xylella fastidiosa: Impact on Microclimate and Social Health

This paper is devoted to the analysis of the impact of changes in olive urban forests affected by Xylella fastidiosa on ecosystem services. The focus is on microclimate and thermal comfort evaluated by two indices: the temperature of equivalent perception (TEP) and the predicted mean vote (PMV), which take into account both microclimate parameters and personal factors (heat resistance of clothing and human activity). The work has been carried out through (i) a qualitative analysis of the potential ecosystem services changes caused by temporary transition from olive groves to uncultivated soil, (ii) a study of the potential change of land use from monumental olive groves to other types of use, and (iii) a quantitative analysis on microclimate impact due to the loss of ecosystem services in two selected neighborhoods located in the Apulia region and chosen due to their proximity to the urban context. The analysis revealed that (i) direct effects on ecosystem services are principally linked with regulation functions and cultural services, (ii) a critical loss of cultural value of monumental olive groves occurred in the two neighborhoods, (iii) such a loss may lead to an increase of TEP and PMV, indicating a decrease of thermal comfort in the whole neighborhoods. Thus, it is necessary to plan the replanting policies of the use of the areas affected by X. fastidiosa not only in terms of agricultural planning but also in terms of landscape, urban planning, and human well-being.