scholarly journals ASSESSMENT OF THE INFLUENCE OF ABIOTIC FACTORS ON THE ENZYMATIVE ACTIVITY OF THE SOIL

ÈKOBIOTEH ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 128-134
Author(s):  
E.V. Tovstik ◽  
◽  
A.S. Olkova ◽  
Keyword(s):  
Enzymatic Activity ◽  
Soil Solution ◽  
Ph Value ◽  
Abiotic Factors ◽  
Inverse Correlation ◽  
Invertase Activity ◽  
Soil Environment ◽  
Factors Affecting ◽  
Activity Of Enzymes ◽  
Made In

Аn attempt is made in this work to establish correlations between the level of enzymatic activity of the soil and factors of an abiotic nature. It was found that the activity of invertase and urease in the soils of more southern territories is higher than that of northern ones. In soils with a pH value of the soil environment close to neutral reaction, the level of enzymatic activity is higher than in more acidic ones. The most sensitive to soil acidity among the studied urease enzymes. In relation to zinc, an inverse correlation was established between its content in the soil and the level of invertase activity. According to the degree of resistance to salinity, the enzymes are arranged in the following order: catalase> invertase> urease. An increase in the mineralization of the soil solution leads to an increase in the activity of urease. Of the studied enzymes, the most labile are representatives of the class of hydrolases (invertase and urease), less labile are oxidoreductases (catalase). Thus, when diagnosing the state of the soil by the level of enzymatic activity, it is necessary to take into account the main abiotic factors affecting the activity of enzymes: the average annual air temperature; pH and mineralization of the soil solution; the content of substances that inhibit microorganisms and block exozymes.

ASSESSMENT OF GRAY FOREST SOIL ENZYMATIC ACTIVITY IN AGRICULTURAL SYSTEMS

2019 ◽  
Keyword(s):  
Enzymatic Activity ◽  
Environmental Sustainability ◽  
Hydrolytic Enzymes ◽  
Invertase Activity ◽  
Phosphorus Cycle ◽  
Soil Enzymatic Activity ◽  
Urease Enzyme ◽  
Natural Analogues ◽  
Activity Of Enzymes ◽  
The Impact

On the grey forest medium-loamy soil of Vladimir Opolye region we have studied the impact of various methods of basic cultivation and fertilizer systems on the activity of redox and hydrolytic enzymes: ure-ase (nitrogen cycle), invertase (carbon cycle), phosphatase (phosphorus cycle), and catalase, involved in the cycle of carbon in the soil. The second humus horizon with capacity of 19-24cm was found at the depth of 20 - 21 cm on the experimental field. We have studied three modes of basic soil cultivation: an-nual shallow flat plowing (6-8 cm), annual deep flat plowing (20-22 cm), and annual moldboard plowing (20-22 cm) with normal and intensive application of fertilizers. The most enzymatically active layer is 0-20 cm. No relevant difference has been found in the level of enzymes activity between variants of basic soil treatment. Activity of enzymes increases with application of fertilizers on the intensive background. In agrogenic soils, soil enzymatic activity is lower on average by 16-22% compared to the soil of the res-ervoir. The biggest negative transformation of activity has been observed at the urease enzyme (up to 50%). With annual moldboard plowing on the intensive backgroung, enzyme activity has been close to the natural level – 98.4%. Catalise and invertase activity in this case were found to be higher (105 and 116% respectively) than that of natural analogues. Activity of enzymes increases with intensive application of fertilizers as compared with normal background. This is particularly evident with 6-8cm deep beardless plowing and 20-22cm deep moldboard plowing. In general, the obtained biochemical indicators charac-terize the highest environmental sustainability of this variation within our research.

scholarly journals Pseudomonas Biocontrol Agents of Soilborne Pathogens: Looking Back Over 30 Years

2007 ◽  
Vol 97 (2) ◽  
pp. 250-256 ◽  
Author(s):  
David M. Weller
Keyword(s):  
Agricultural Soils ◽  
Abiotic Factors ◽  
Biocontrol Agents ◽  
Future Research ◽  
Soilborne Pathogens ◽  
Factors Affecting ◽  
Tremendous Progress ◽  
Pathogen Suppression ◽  
Rhizosphere Competence ◽  
Made In

Pseudomonas spp. are ubiquitous bacteria in agricultural soils and have many traits that make them well suited as biocontrol agents of soilborne pathogens. Tremendous progress has been made in characterizing the process of root colonization by pseudomonads, the biotic and abiotic factors affecting colonization, bacterial traits and genes contributing to rhizosphere competence, and the mechanisms of pathogen suppression. This review looks back over the last 30 years of Pseudomonas biocontrol research and highlights key studies, strains, and findings that have had significant impact on shaping our current understanding of biological control by bacteria and the direction of future research.

Kinetic and thermodynamic study of the adsorption of calcium onto sugar beet pulp

2016 ◽  
pp. 565-570
Author(s):  
Huang Qin ◽  
Zhu Si-ming ◽  
Zeng Di ◽  
Yu Shu-juan
Keyword(s):  
Sugar Beet ◽  
Adsorption Equilibrium ◽  
Ph Value ◽  
Hard Water ◽  
Sugar Beet Pulp ◽  
Order Kinetic ◽  
Factors Affecting ◽  
Isotherm Equation ◽  
Equilibrium Data ◽  
Beet Pulp

Sugar beet pulp (SBP) was used as low value adsorbent for the removal of calcium from hard water. Batch experiments were conducted to determine the factors affecting adsorption of the process such as pH value and Ca concentration. The adsorption equilibrium of Ca2+ by the SBP is reached after 100min and a pseudo second-order kinetic model can describe the adsorption process. The initial concentrations of Ca varied from 927 to 1127mgCa2+/L. A dose of 30g/L sugar beet pulp was sufficient for the optimum removal of calcium. The overall uptake of Ca ions by sugar beet pulp has its maximum at pH=8. The adsorption equilibrium data fitted well with the Langmuir adsorption isotherm equation.

scholarly journals Effect of Sulfate-Reducing Bacteria (SRB) on the Corrosion of Buried Pipe Steel in Acidic Soil Solution

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 625
Author(s):  
Lijuan Chen ◽  
Bo Wei ◽  
Xianghong Xu
Keyword(s):  
Soil Solution ◽  
Steel Surface ◽  
Pipeline Steel ◽  
Electrochemical Techniques ◽  
Sulfate Reducing Bacteria ◽  
Acidic Soil ◽  
Microbiologically Influenced Corrosion ◽  
Soil Environment ◽  
Sulfate Reducing ◽  
Reducing Bacteria

The influence of sulfate-reducing bacteria (SRB) on the corrosion behaviors of X80 pipeline steel was investigated in a soil environment by electrochemical techniques and surface analysis. It was found that SRB grew well in the acidic soil environment and further attached to the coupon surface, resulting in microbiologically influenced corrosion (MIC) of the steel. The corrosion process of X80 steel was significantly affected by the SRB biofilm on the steel surface. Steel corrosion was inhibited by the highly bioactive SRB biofilm at the early stage of the experiment, while SRB can accelerate the corrosion of steel at the later stage of the experiment. The steel surface suffered severe pitting corrosion in the SRB-containing soil solution.

scholarly journals Factors Affecting Students’ Choice for MBA Program in Kuwait Universities

2016 ◽  
Vol 11 (3) ◽  
pp. 119 ◽  
Author(s):  
Abdullah AL-Mutairi ◽  
Muna Saeid
Keyword(s):  
Sources Of Information ◽  
Mba Programs ◽  
Factors Affecting ◽  
Knowledge And Skills ◽  
University Websites ◽  
Mba Program ◽  
Campus Visit ◽  
Admission Requirements ◽  
Structured Questionnaire ◽  
Made In

The attempt is made in this study to identify students’ motives and reasons behind enrolling in a MBA program offered by universities operating in Kuwait. It also explores criterion used to select the program. To achieve these objectives, data were collected through a well-designed and structured questionnaire and pre-testing was carried out to examine the efficiency of the instrument. The study showed that the main reasons behind selecting the MBA program by students are to satisfy their personal concerns and improve their knowledge and skills. Moreover, the students used program alumni and campus visit as main sources of information followed by friends’ suggestions and university websites. When evaluating the MBA programs, the students cited overseas accreditation as the most used criteria followed by faculty reputation, institution reputation and admission requirements.

scholarly journals AGE OF THE HOST AND OTHER FACTORS AFFECTING THE PRODUCTION WITH URETHANE OF PULMONARY ADENOMAS IN MICE

1951 ◽  
Vol 93 (5) ◽  
pp. 427-449 ◽  
Author(s):  
Stanfield Rogers
Keyword(s):  
Age Differences ◽  
Proliferative Activity ◽  
Major Part ◽  
Inverse Correlation ◽  
Alveolar Cells ◽  
Pulmonary Tissue ◽  
Factors Affecting ◽  
Neoplastic Change ◽  
Nuclear Changes ◽  
Old Mice

Young, rapidly growing mice are greatly more responsive to the adenoma-inducing influence of urethane than are those just arriving at maturity. This is manifest both in the proportion of animals developing the tumors and in their number per individual. An amount of urethane per gram body weight which suffices to induce adenomas in only an occasional 8-week-old animal will cause them to appear in quantity in more than half the 3-week-old mice injected. There is an almost absolute inverse correlation between the rate of growth of the pulmonary tissue between the ages of 2 and 10 weeks and the response to urethane in terms of adenomas. Hence the conclusion seems justified that the natural proliferative activity of the alveolar cells during youth plays a major part in the formation of the tumors. After the 6th week the age differences become relatively slight, yet there is reason to think that they continue in some degree as life goes on. Urethane has no effect to promote multiplication of the cells it has rendered neoplastic, its whole role being to initiate neoplastic change. The abnormalities induced by urethane in the nucleus of normal and neoplastic cells, as observed by previous workers, have suggested that the substance brings about the adenomatous state by acting upon the nucleus. But colchicine, also a karyolytic poison causing pronounced nuclear changes, does not alter in the least the yield of adenomas to urethane when administered concurrently. Nor does fasting influence the yield, though it markedly reduces mitotic activity. The meaning of these facts is discussed.

scholarly journals Abiotic factors affecting habitat selection by two invasive gammarids Dikerogammarus villosus and Pontogammarus robustoides

Hydrobiologia ◽  
2017 ◽  
Vol 797 (1) ◽  
pp. 247-263 ◽  
Author(s):  
Jarosław Kobak ◽  
Łukasz Jermacz ◽  
Joanna Marcińczyk ◽  
Ewa Bartoszyńska ◽  
Daria Rutkowska ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Abiotic Factors ◽  
Factors Affecting ◽  
Dikerogammarus Villosus ◽  
Pontogammarus Robustoides

scholarly journals HYGIENIC EVALUATION OF ILLUMINATION INDICES AND NON-IONIZING RADIATION AT EDUCATIONAL SITES OF HIGH SCHOOLS

2020 ◽  
Vol 99 (2) ◽  
pp. 152-157
Author(s):  
Elena Yu. Gorbatkova ◽  
T. R. Zulkarnaev ◽  
Z. A. Khusnutdinova ◽  
U. Z. Ahmadullin ◽  
A. A. Kazak ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Educational Institutions ◽  
Educational Organizations ◽  
Higher Educational Institutions ◽  
Factors Affecting ◽  
Republic Of Bashkortostan ◽  
Higher Educational ◽  
The Republic ◽  
The Government ◽  
Made In

One of the significant factors affecting the condition of the students’ visual apparatus is an illumination level in the premises of educational organizations. Electromagnetic radiation arising from computers also has an essential influence on a state of health. Taking into account the urgency of this problem, an analysis of illumination indices and EM radiation was made in audiences of higher educational institutions of various profiles (Ufa, the Republic of Bashkortostan). The total number of illumination measurements was 3528. The measurement methods met the requirements of the interstate standard. According to the results of the illumination indices estimation in the studied universities, a significant deviation from the regulated norms was revealed: in 71.5% of the measurements the index was below the norm. It should be noted that indices differed significantly depending on the type of educational organization. The best situation is in the “Financial University under the Government of the Russian Federation,” where only 13.3% of the measurements are inconsistent with the normative indices. Pulsation coefficient also was determined. It turned out that 88.8% of the measurements do not correspond to the norm. The analysis of illumination measurements in computer classes was carried out. Only one-fifth of them in the computer table working area in the of the document placement corresponded to SanPin. An anonymous questionnaire was also organized for students from four leading universities in Ufa, the Republic of Bashkortostan. According to respondents’ answers, out of seven students, one was revealed to be suffering from myopia. On the basis of “Center for Hygiene and Epidemiology in the Republic of Bashkortostan”, a study of non-ionizing radiation from video terminals located in computer classes was made. 1145 measurements were made in 20 buildings of four universities studied. It was found out that the intensity of the electrostatic field did not meet the requirements of SanPiN in 5.7% of the measurements. Hygienic assessment of the environment of educational organizations of various profiles revealed a number of significant deviations from the regulated norms. The obtained results testify to the need to monitor the illumination and EMR indices both from the administration of higher education institutions and from teachers. Based on the results of the study, recommendations were prepared for the management of higher educational institutions in Ufa.

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