scholarly journals MICROBIOTA OF URBAN SOILS OF GREEN PLANTATIONS OF KYIV WITH THE ADDITION OF SILICON-CONTAINING COMPOUNDS

2021 ◽  
Vol 26 (1(48)) ◽  
pp. 45-54
Author(s):  
N. E., Ellanska ◽  
O. P. Yunosheva
Keyword(s):  
Functional Organization ◽  
Soil Formation ◽  
Urban Ecosystems ◽  
Botanical Garden ◽  
Trophic Relations ◽  
Soil Microbial ◽  
Natural Substances ◽  
Microbiological Methods ◽  
Before And After ◽  
Microbial Groups

Problem. Intensive human pressure on urban ecosystems in big cities, such as Kyiv, leads to cenotic and trophic relations disbalance, agronomically useful microbiota and microfauna inhibition, plant resistance to any stressors decrease and disruption of normal soil formation. Therefore, it is important to find new effective, economically viable and environmentally safe methods to overcome soil sickness in city plantations. Aim. To study the structural and functional peculiarities of organization of soil microbial groups in anthropogenically disturbed zones of Kyiv green plantations in order to overcome soil fatigue with the use of natural substances - silicon-containing mineral analcime. Methods. Investigations were carried out on the basis of the National Botanical Garden M.M. Gryshko NAS of Ukraine, Department of Allelopathy. Six research regions in the most сontaminated and anthropogenically disturbed green areas of the Kyiv Obolonsky district were selected as objects. Twice a year, samples of root soil were taken at 0-20 cm depth before application (May) and 3.5 months after application of silicon-containing mixture (analcime) (September). The selection of soil samples, preparation and saving for the study of aerobic microbiota were carried out in accordance with ISO 10381-6-2001. The quantity of microorganisms of main ecological and trophic groups, direction of microbiological processes, identification of soil micromycetes were determined by conventional microbiological methods. Results. The results of this work showed that 3.5 months after the addition of the silicon-containing mixture, there were significant changes in the structure of the soil microbiocenosis. The increase in the number of microorganisms involved in the transformation of nitrogen compounds and the reduction of phytotoxic forms of soil fungi were detected, which indicates favorable conditions for the synthesis of humic compounds. The biggest changes were observed on the side of the highway with active emissions from automobiles and in the park, where higher content of iron ions was determined in the water for irrigation. Conclusions. The conducted research made it possible to estimate the structural and functional organization of microbial groups of the soils in a separate Kyiv district under different anthropogenic influence before and after the addition of silicon-containing mixture.

scholarly journals Disentangling Responses of the Subsurface Microbiome to Wetland Status and Implications for Indicating Ecosystem Functions

2021 ◽  
Vol 9 (2) ◽  
pp. 211
Author(s):  
Jie Gao ◽  
Miao Liu ◽  
Sixue Shi ◽  
Ying Liu ◽  
Yu Duan ◽  
...  
Keyword(s):  
Microbial Community ◽  
High Throughput Sequencing ◽  
Carbon Fixation ◽  
Microbial Community Composition ◽  
Ecosystem Functions ◽  
Microbial Composition ◽  
Wetland Ecosystems ◽  
Soil Microbial ◽  
Geochemical Properties ◽  
Microbial Groups

In this study, we analyzed microbial community composition and the functional capacities of degraded sites and restored/natural sites in two typical wetlands of Northeast China—the Phragmites marsh and the Carex marsh, respectively. The degradation of these wetlands, caused by grazing or land drainage for irrigation, alters microbial community components and functional structures, in addition to changing the aboveground vegetation and soil geochemical properties. Bacterial and fungal diversity at the degraded sites were significantly lower than those at restored/natural sites, indicating that soil microbial groups were sensitive to disturbances in wetland ecosystems. Further, a combined analysis using high-throughput sequencing and GeoChip arrays showed that the abundance of carbon fixation and degradation, and ~95% genes involved in nitrogen cycling were increased in abundance at grazed Phragmites sites, likely due to the stimulating impact of urine and dung deposition. In contrast, the abundance of genes involved in methane cycling was significantly increased in restored wetlands. Particularly, we found that microbial composition and activity gradually shifts according to the hierarchical marsh sites. Altogether, this study demonstrated that microbial communities as a whole could respond to wetland changes and revealed the functional potential of microbes in regulating biogeochemical cycles.

Feedforward Inhibition Controls the Spread of Granule Cell–Induced Purkinje Cell Activity in the Cerebellar Cortex

2007 ◽  
Vol 97 (1) ◽  
pp. 248-263 ◽  
Author(s):  
Fidel Santamaria ◽  
Patrick G. Tripp ◽  
James M. Bower
Keyword(s):  
Cerebellar Cortex ◽  
Granule Cells ◽  
Functional Organization ◽  
Cerebellar Granule Cells ◽  
Molecular Layer ◽  
Cell Activity ◽  
Excitatory Input ◽  
Cortical Inhibition ◽  
Before And After

Synapses associated with the parallel fiber (pf) axons of cerebellar granule cells constitute the largest excitatory input onto Purkinje cells (PCs). Although most theories of cerebellar function assume these synapses produce an excitatory sequential “beamlike” activation of PCs, numerous physiological studies have failed to find such beams. Using a computer model of the cerebellar cortex we predicted that the lack of PCs beams is explained by the concomitant pf activation of feedforward molecular layer inhibition. This prediction was tested, in vivo, by recording PCs sharing a common set of pfs before and after pharmacologically blocking inhibitory inputs. As predicted by the model, pf-induced beams of excitatory PC responses were seen only when inhibition was blocked. Blocking inhibition did not have a significant effect in the excitability of the cerebellar cortex. We conclude that pfs work in concert with feedforward cortical inhibition to regulate the excitability of the PC dendrite without directly influencing PC spiking output. This conclusion requires a significant reassessment of classical interpretations of the functional organization of the cerebellar cortex.

Functional organization of ciliary muscle in the cat

1962 ◽  
Vol 203 (5) ◽  
pp. 857-859 ◽  
Author(s):  
Harris Ripps ◽  
Irwin M. Siegel ◽  
William B. Getz
Keyword(s):  
Functional Organization ◽  
Muscle Cells ◽  
Nerve Fibers ◽  
Fixed Number ◽  
Ciliary Muscle ◽  
Frequency Variation ◽  
Efferent Nerve ◽  
Ocular Accommodation ◽  
Before And After ◽  
Stimulation Of

Ocular accommodation was elicited by electric stimulation of the ciliary ganglion in cats. The responses to frequency variation were recorded before and after cutting a branch of the postganglionic motor supply to the ciliary muscle. At all stimulus frequencies the responses obtained after section were shown to be a constant fraction of those obtained in the intact preparation. This suggests that a fixed number of muscle cells are affected when a portion of the efferent nerve fibers is cut. It was concluded that smooth ciliary muscle is organized as independent functional units, akin to the motor-unit arrangement of skeletal muscle; a given nerve fiber influences the response of a limited number of muscle cells.

scholarly journals Identification of new microbial functional standards for soil quality assessment

2019 ◽  
Author(s):  
Sören Thiele-Bruhn ◽  
Michael Schloter ◽  
Berndt-Michael Wilke ◽  
Lee A. Beaudette ◽  
Fabrice Martin-Laurent ◽  
...  
Keyword(s):  
Plant Growth ◽  
Nutrient Cycling ◽  
Greenhouse Gas ◽  
Soil Quality ◽  
Plant Growth Promotion ◽  
Ecosystem Service ◽  
Enzyme Activities ◽  
Growth Promotion ◽  
Soil Microbial ◽  
Microbiological Methods

Abstract. The activity of microorganisms in soil is important for a robust functioning soil and related ecosystem service. Hence, there is a necessity to identify the indigenous soil microbial community for its functional properties using soil microbiological methods in order to determine the natural properties, functioning and operating range of soil microbial communities, and to assess ecotoxicological effects due to anthropogenic activities. Numerous microbiological methods currently exist in the literature and new, more advanced methods continue to be developed; however, only a limited number of the methods are standardized. Consequently, there is a need to identify the most promising non-standardized methods for assessing soil quality and develop these into standards. In alignment with the "Ecosystem Service Approach", new methods should focus on soil microbial function, including nutrient cycling, pest control and plant growth promotion, carbon cycling and sequestration, greenhouse gas emission, and soil structure. The few existing, function-related standard methods available focus on the estimation of microbial biomass, basal respiration, enzyme activities related to nutrient cycling, and organic chemical biodegradation. This paper sets out to summarize and expand on recent discussions within the International Organization for Standardization (ISO), Soil Quality - Biological Characterization sub-committee (ISO TC 190/SC 4) where a need was identified to develop scientifically sound methods which would best fulfil the practical needs of future users for assessing soil quality. Of particular note was the current evolution of molecular methods in microbial ecology that uses quantitative real time PCR (qPCR) to produce a large number of new endpoints and is more sensitive as compared to "classical" methods. Quantitative PCR assesses the activity of microbial genes that code for enzymes that catalyse major transformation steps in nitrogen and phosphorus cycling, greenhouse gas emissions, chemical transformations including pesticide degradation, and plant growth promotion pathways. In the assessment of soil quality methods, it was found that fungal methods were significantly underrepresented. As such, techniques to analyse fungal enzyme activities are proposed. Additionally, methods for the determination of microbial growth rates and efficiencies, including the use of glomalin as a biochemical marker for soil aggregation, are discussed. Furthermore, field methods indicative of carbon turnover, including the litter bag test and a modification to the tea bag test, are presented. As a final note, it is suggested that endpoints should represent a potential function of soil microorganisms rather than actual activity levels, as the latter can largely be dependent on short-term variable soil properties such as pedoclimatic conditions, nutrient availability, and anthropogenic soil cultivation activities.

The influence of light on soil community structure and consequences for soil CO2, CO18O and COS exchange

2020 ◽  
Author(s):  
Lisa Wingate ◽  
Clement Foucault ◽  
Nicolas Fanin ◽  
Joana Sauze ◽  
Pierre-Alain Maron ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Soil Ph ◽  
Isotope Composition ◽  
Light Availability ◽  
Alkaline Soils ◽  
Soil Microbial ◽  
Microbial Groups ◽  
Taxonomic Groups ◽  
Carbonyl Sulphide

<p>The stable oxygen isotope composition of atmospheric CO<sub>2</sub> and the mixing ratio of carbonyl sulphide (COS) are potential tracers of biospheric CO<sub>2</sub> fluxes at large scales. However, the use of these tracers hinges on our ability to understand and better predict the activity of the enzyme carbonic anhydrase (CA) in different soil microbial groups, including phototrophs. Because different classes of the CA family (α, β and γ) may have different affinities to CO<sub>2</sub> and COS and their expression should also vary between different microbial groups, differences in the community structure could impact the ‘community-integrated’ CA activity differently for CO<sub>2</sub> and COS. Four soils of different pH were incubated in the dark or with a diurnal cycle for forty days to vary the abundance of native phototrophs. Fluxes of CO<sub>2</sub>, CO<sup>18</sup>O and COS were measured to estimate CA activity alongside the abundance of bacteria, fungi and phototroph genes. The abundance of soil phototrophs increased most at higher soil pH. In the light, the strength of the soil CO<sub>2</sub> sink and the CA-driven CO<sub>2</sub>-H<sub>2</sub>O isotopic exchange rates correlated with phototroph abundance. COS uptake rates were attributed to fungi whose abundance was positively enhanced in alkaline soils but only in the presence of increased phototrophs. In addition we developed a metabarcoding approach to reveal the interactions of specific taxonomic groups incuding photosynthetic eukaryotic algae and cyanobacteria when exposed to light and their impact on flux rates. Our findings demonstrate that soil-atmosphere CO<sub>2</sub>, COS and CO<sup>18</sup>O fluxes are strongly regulated by the microbial community structure in response to changes in soil pH and light availability and support the idea that different members of the microbial community express different classes of CA, with different affinities to CO<sub>2</sub> and COS.</p>

Distribution Characters of Soil Microbial in Wuzhi Part of Yellow River Riparian Wetland after Artificial Restoration

2012 ◽  
Vol 518-523 ◽  
pp. 5030-5034
Author(s):  
Ning Zhu ◽  
Tong Qian Zhao ◽  
Chun Yan Xiao ◽  
Li Heng Jiao ◽  
Kun Feng Zhang
Keyword(s):  
Yellow River ◽  
Typha Angustifolia ◽  
Distribution Characteristics ◽  
Phragmites Communis ◽  
Polygonum Hydropiper ◽  
Riparian Wetland ◽  
Soil Microbial ◽  
Bare Land ◽  
Before And After ◽  
Artificial Restoration

Abstract: This article describes the distribution characteristics of soil microbial in different vegetable types in artificial wetland restoration. The results show that quantity of microbial had a significant increase before and after restoration. The value of Polygonum hydropiper sample was largest. The sequence of increase was Polygonum hydropiper,Phragmites communis Trin,Typha angustifolia and bare land; Referring to the change of three types of microorganisms, bacteria enhance 2.16 times largest; Meanwhile fungi go up 1.11 times least. The range of microbial diversity value before restoration is 0.2437-0.7633, and after is 0.1163-0.4069;Bacteria amount had significant correlation with TN.

scholarly journals Impact of cadmium and lead on soil microbial biomass nitrogen of the botanical garden of ahmadu bello university, Zaria, Nigeria

2018 ◽  
Vol 3 (3) ◽  
pp. 94-97
Author(s):  
Oijagbe IJ ◽  
Abubakar BY ◽  
Edogbanya PRO
Keyword(s):  
Microbial Biomass ◽  
Room Temperature ◽  
Soil Microbial Biomass ◽  
Botanical Garden ◽  
Soil Samples ◽  
Microbial Biomass Nitrogen ◽  
Soil Microbial ◽  
Soil Microbial Biomass Nitrogen ◽  
Cadmium And Lead ◽  
Chloride Salts

This study is aimed at evaluating the effect of heavy metals on soil microbial processes. The effects of Lead (Pb) and Cadmium (Cd) at different concentrations were investigated over a period of eight weeks. Chloride salts of Pb and Cd were added singly and in combination to soil samples at room temperature (27°C) in different polythene bags. Samples were taken from the bags at two weeks interval and measurements were taken of the rate of microbial biomass nitrogen (MBN). The results showed that there was a significant decrease in the microbial biomass for all treated soils from the second week to the sixth week. But there was an observed increase in microbial biomass Nitrogen on the eight week. On the 6thweek, 40mgkg-1Cd gave the most significant decrease (16µg/g) and 1000mgkg-1 Pb gave the least significant decrease (70µg/g) of MBN.

scholarly journals Urban ornamental plants for sustenance of wild bees (Hymenoptera, Apoidea)

2020 ◽  
Vol 85-86 ◽  
Author(s):  
G.Y. Honchar ◽  
A.M. Gnatiuk
Keyword(s):  
Ornamental Plants ◽  
Botanical Garden ◽  
Common Species ◽  
Residential Areas ◽  
Wild Bees ◽  
Trophic Relations ◽  
Phenological Data ◽  
Green Areas ◽  
Data Book ◽  
Urban Conditions

The aim of our study was to assess the attraction and value of flowering plants at green areas in support and sustenance of wild bees (Hymenoptera, Apoidea) populations in Kyiv. Study objects were the most common flowering ornamental plants of the city and the wild bees visiting their inflorescence during the vegetation season to collect pollen and feed on nectar. Study was conducted at 16 areas of observation and material collection, which include urban parks, M. M. Gryshko National Botanical Garden, green spaces of residential areas, roadsides, etc. Insects were collected following the standard method of catching individual specimens during spring and summer periods of 2012–2018. Based on the observations, we visualized trophic relations of bees with plants and calculated the biodiversity index of visiting insects for plants. Periodicity of florescence was analyzed using phenological data. Examination of urban green areas revealed ornamental plants that were the most attractive for bees, including more than 35 taxa of 20 families of trees, shrubs and grassy plants. Bees are superiorly attracted to plants of the genera Rudbeckia, Sedum, Gypsophila, Cerasus, Tagetes, Spiraea, Lonicera, Aesculus. There is a succession of plant flowering during spring-summer season, which must be considered while planting of greenery. Certain plant species attract insects at each period of inflorescence period, for example, Prunus, Rhododendron, Crataegus, Aesculus in spring, most of Asteraceae in summer. The diversity of blossoming plants is significantly lower to the end of summer and beginning of fall, coinciding with the decreasing flight activity of wild bees. Overall, the studied ornamental plants not only attract the most common species of wild bees, but also highly specific and rare species such as Bombus argillaceus and Xylocopa valga, protected by the Red Data Book of Ukraine. We found that blossoming green areas, made up by trees, shrubs and herbs ornamental plants, are important for feeding of many species of wild bees and sustaining their populations in urban conditions.

scholarly journals The Relationship Between the Use of Hydrogel and Silicone Hydrogel Contact Lenses and Coagulase-Negative Staphylococci Population in the Conjunctiva and Biofilm Forming Staphylococcus epidermidis

2021 ◽  
Author(s):  
Zeynep Güngördü Dalar ◽  
Güzin İskeleli ◽  
Mert Ahmet Kuşkucu ◽  
Mehmet Demirci ◽  
Penbe Çağatay ◽  
...  
Keyword(s):  
Contact Lens ◽  
Staphylococcus Epidermidis ◽  
Congo Red ◽  
Molecular Methods ◽  
Coagulase Negative Staphylococci ◽  
Silicone Hydrogel ◽  
Slime Production ◽  
Microbiological Methods ◽  
Cutibacterium Acnes ◽  
Before And After

Objective: The most important bacteria of the conjunctival microbiota are Staphylococcus epidermidis, diphteroid rods, Corynebacterium spp. and Cutibacterium acnes. Especially biofilm formation of S. epidermidis is very important for contact lens related infections. For this purpose, we aimed to examine the changes in the presence of biofilm-forming S. epidermidis and other coagulase-negative staphylococci in conjunctival swabs taken before and after lens usage in 140 patients (90 hydrogel, 50 silicone hydrogel) who were prepared to wear lenses. Methods: Coagulase-negative staphylococci isolated from the conjunctival microbiota identified standard clinical microbiological methods, after identification of S.epidermidis strains with API Staph; Slime production was determined by Congo red agar, standard tube and molecular methods. Results: S.epidermidis was the most frequently isolated species in conjunctival microbiota before and after lens usage. Before lens usage, slime positive S. epidermidis strains were found as 45-50% but after lens usage it was 59% in hydrogel contact lens users and 70.2% in silicone hydrogel contact lens users. For the investigation of slime production, 82 (50.9%) of 161 S. epidermidis strains were found positive by using Congo red agar, 61 (37.8%) by standard tube method and 91 (56.5%) by molecular methods. Conclusion: The result of our study suggests that there are no significant changes in bacterial ratios before and after lens use, but bacteria such as S. epidermidis can predispose to infections by using slime production and contact lens factor. Also; molecular methods and Congo Red Agar method were found to be more reliable than the Standard Tube method.

scholarly journals Soil Microbial Activity and Diversity in Response to Soil Chemical Factors in Agricultural Soils

2019 ◽  
Vol 24 (1) ◽  
pp. 43
Author(s):  
Lily Ishak ◽  
Philip Hugh Brown
Keyword(s):  
Microbial Communities ◽  
Agricultural Soils ◽  
Soil Health ◽  
Soil Microbial Communities ◽  
Soil Microbial Activity ◽  
Soil Microbial Diversity ◽  
Soil Microbial ◽  
Microbial Responses ◽  
Chemical Factors ◽  
Microbial Groups

The role of microbial communities in maintaining soil health is mostly influenced by chemical condition of soil. Microbial communities vary in response to soil chemical factors. The contradictive results from previous findings emphasise that it is difficult to define a pattern of the influence of soil chemical factors on soil microbial diversity and activity. The aim of the study was to assess soil microbial responses to soil chemical factors in agricultural soils. Composite soil (Dermosol order) samples taken from 16 commercial crop sites in Bundaberg, Queensland, Australia, were chemically and biologically analysed. It was found that bacterial and fungal activity and diversity were significantly affected by soil EC, SOM and NO3-N content, but were not influenced by soil pH, CEC, and Ca:Mg ratio. The diversity of bacterial and fungal communities displayed a positive linear relationship with soil EC, whereas the activity and diversity of these two microbial groups and SOM displayed a significant quadratic relationship. The finding suggested that microbial community was predominantly influenced by SOM content.

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