Partial segregation of bacteria and isolation of Pythium from the coarser soil fractions.

1954 ◽  
Vol 5 (4) ◽  
pp. 702 ◽  
Author(s):  
HR Angell
Keyword(s):  
Bacterial Population ◽  
Surface Soil ◽  
Aqueous Suspension ◽  
Soil Samples ◽  
Australian Capital Territory ◽  
Fungal Population ◽  
Australian Capital ◽  
Supernatant Liquid ◽  
The Mean ◽  
Bacteria And Fungi

Soil collected in the Australian Capital Territory was divided into fractions by sieving and subsequent deposition from aqueous suspensions. The greater proportion of the Pythium, and indeed the fungal population, was found, by plating, to be concentrated in the coarser portion of the soil, most of the bacterial population being in the colloidal part. After deposition of the colloids for 4 weeks, and with them the bacteria, a mean of less than one bacterium was plated per ml of supernatant liquid. The separation of bacteria and fungi facilitated the isolation of Pythium. The Pythium population of the surface soil was about 1000 per g. The mean number of isolates of Pythium in 11 other surface soil samples was 1.7 per mg using the fraction sedimenting from an aqueous suspension in 5 min. In similar fractions of soil taken at 18 and 24 in. below the surface the number of Pythium isolates was 3 per 10 mg.

scholarly journals EFFECTS OF SOIL SOLARIZATION ON FUNGAL AND BACTERIAL POPULATIONS ASSOCIATED WITH AMARANTHIS VIRIDIS L. (AFRICAN SPINACH) IN LAGOS, NIGERIA

2021 ◽  
Vol 2 (2) ◽  
pp. 133-153
Author(s):  
O. T. Yahaya ◽  
D. C. Obadiah ◽  
O. E. Oladele ◽  
C. Obi ◽  
O. J. Edache ◽  
...  
Keyword(s):  
Proximate Analysis ◽  
Soil Samples ◽  
Soil Solarization ◽  
Effective Strategy ◽  
Control Soil ◽  
Environment Friendly ◽  
Bacterial Populations ◽  
The Mean ◽  
Bacteria And Fungi ◽  
Experimental Trials

Soil solarization is increasingly used to control soil-borne pathogens because it is environment-friendly. However, performance varied geographically, necessitating experimental trials before its introduction. This study assessed the effects of solarization on soil-borne bacteria and fungi, growth, and proximate composition of Amaranthus viridis (African spinach) in Lagos, Nigeria. Two raised beds were solarized for six weeks with a transparent and black polyethylene sheet, and a non-solarized (control) bed was equally made. The vegetable seeds were planted and their growths were recorded for four weeks. Soil samples at 15-20cm deep and leaves were obtained for microbiological and proximate analysis, respectively. The mean temperature of transparent xxpolyethylene’s soil was 45.33 oC, black polyethylene (35 oC), and non-solarized (33.50 oC). The mean height and width of transparent polyethylene’s A. viridis were 24 and 3cm, black polyethylene (19 and 2.2 cm), and non-solarized (17 and 1.6cm). The transparent polyethylene’s soil had 3100 and 250 cfu/g bacterial and fungal colonies, black polyethylene (3200 and 1900 cfu/g), and non-solarized (37000 and 1900 cfu/g), respectively. The proximate contents of the transparent polyethylene’s A. viridis were (70 moisture, 10 ash, 4.24 protein, 1.45 fat and 9.94 % fibre), black polyethylene (73.35 moisture, 8.36 ash, 3.1% protein, 1.23 fat, and 6.77 % fibre), and non-solarized (76.09 moisture, 5.91 protein, 3.15 ash, 1.31 fat and 6.75 % fibre). Overall, statistical differences (p ≤ 0.05) existed between the solarized and non-solarized and between transparent and black polyethylene (transparent>black>non-solarized). Thus, solarization could be an effective strategy for controlling soil-borne bacteria and fungi of A. viridis in the area studied.

scholarly journals Natural radioactivity in the soil of Thoulakhom district in Vientiane province, Laos

2019 ◽  
Vol 2 (4) ◽  
pp. 119-125
Author(s):  
Sonexay Xayheungsy ◽  
Khiem Hong Le
Keyword(s):  
Activity Concentration ◽  
Democratic Republic ◽  
Surface Soil ◽  
Natural Radionuclides ◽  
Soil Samples ◽  
Radiation Hazard ◽  
Gamma Spectrometer ◽  
Mean Values ◽  
Activity Concentrations ◽  
The Mean

Results of the first investigation of the activity concentration of the surface soil samples collected at various locations of Thoulakhom district of Vientiane province of Laos People's Democratic Republic (PDR) are presented in this work. The activity concentration of the natural radionuclides 226Ra, 232Th and 40K in the soil samples were determined by gamma spectrometer using a highenergy resolution semiconductor detector HPGe. The activity concentrations of the natural radionuclides were in the range from 11.28 to 31.46 with the mean of 21.76 Bq.kg-1 for 226Ra, from 7.13 to 44.47 with the mean of 21.85 Bq.kg-1 for 232Th and from 8.96 to 581.52 with the mean of 112.89 Bq.kg-1 for 40K. These mean values of the activity concentration were lower than the average worldwide ones, which were 33, 45 and 420 Bq.kg-1 for 226Ra, 232Th, and 40K, respectively. The results indicate dthat the radiation hazard from natural 226Ra, 232Th, and 40K radionuclides in all investigated soil samples taken from area under investigation in this work was not significant.

Orientation of tawny frogmouth (Podargus strigoides) nests and their position on branches optimises thermoregulation and cryptic concealment

2013 ◽  
Vol 61 (6) ◽  
pp. 469 ◽  
Author(s):  
Stuart Rae ◽  
Duncan Rae
Keyword(s):  
Tree Species ◽  
Prevailing Wind ◽  
Australian Capital Territory ◽  
Australian Capital ◽  
Nest Sites ◽  
North East ◽  
The North ◽  
Sclerophyll Forest ◽  
The Mean ◽  
Nest Height

Tawny frogmouth (Podargus strigoides) nests were surveyed in grassy woodland, dry sclerophyll forest and suburbia in the Australian Capital Territory. In total, 253 tawny frogmouth nests were recorded in 145 nest sites. Nests were oriented to the north-east, which would expose them to morning sunshine and partially shelter them from the prevailing wind. Most nests were placed in rough or flaky-barked tree species, on open mid-branch sites with no foliage, where the birds’ plumage and posture resemble the colour and form of the branches. Although smooth-barked gum trees were the most abundant types in the dry sclerophyll forest they were seldom used. Nest sites in all habitats were similar; the mean nest height was 9.2 m, and most nests were set on forks in the lowest branches. By placing their nests in these positions tawny frogmouths likely maximise their potential thermoregulation, protection from wind, concealment from predators, and detection of approaching predators.

COUNTING TOTAL BACTERIA IN LAND ORGANIC WASTE HOUSEHOLD AND LAND INORGANIC WITH TOTAL PLATE COUNT METHOD (TPC)

2017 ◽  
Vol 4 (2) ◽  
pp. 87-91
Author(s):  
Ekamaida Ekamaida
Keyword(s):  
Soil Fertility ◽  
Bacterial Population ◽  
Organic Soil ◽  
Biological Properties ◽  
Plate Count ◽  
Bacterial Populations ◽  
Fertility Data ◽  
Plate Count Method ◽  
The Mean ◽  
Total Bacteria

The soil fertility aspect is characterized by the good biological properties of the soil. One important element of the soil biological properties is the bacterial population present in it. This research was conducted in the laboratory of Microbiology University of Malikussaleh in the May until June 2016. This study aims to determine the number of bacterial populations in soil organic and inorganic so that can be used as an indicator to know the level of soil fertility. Data analysis was done by T-Test that is by comparing the mean of observation parameter to each soil sample. The sampling method used is a composite method, which combines 9 of soil samples taken from 9 sample points on the same plot diagonally both on organic soil and inorganic soil. The results showed the highest bacterial population was found in total organic soil cfu 180500000 and total inorganic soil cfu 62.500.000

scholarly journals Five-Year Enhanced Natural Attenuation of Historically Coal-Tar-Contaminated Soil: Analysis of Polycyclic Aromatic Hydrocarbon and Phenol Contents

2021 ◽  
Vol 18 (5) ◽  
pp. 2265
Author(s):  
Arkadiusz Telesiński ◽  
Anna Kiepas-Kokot
Keyword(s):  
Aromatic Hydrocarbons ◽  
Natural Attenuation ◽  
Soil Analysis ◽  
Coal Tar ◽  
Soil Samples ◽  
Lower Intensity ◽  
Sampling Points ◽  
Polycyclic Aromatic ◽  
Monoaromatic Hydrocarbons ◽  
The Mean

The objective of this study was to assess the soil pollution on an industrial wasteland, where coal-tar was processed in the period between 1880 and 1997, and subsequent to assess the decline in the content of phenols and polycyclic aromatic hydrocarbons (PAHs) during enhanced natural attenuation. The soil of the investigated area was formed from a layer of uncompacted fill. Twelve sampling points were established in the investigated area for collecting soil samples. A study conducted in 2015 did not reveal any increase in the content of heavy metals, monoaromatic hydrocarbons (BTEX), and cyanides. However, the content of PAHs and phenols was higher than the content permitted by Polish norms in force until 2016. In the case of PAHs, it was observed for individual compounds and their total contents. Among the various methods, enhanced natural attenuation was chosen for the remediation of investigated area. Repeated analyses of the contents of phenols and PAHs were conducted in 2020. The results of the analyses showed that enhanced natural attenuation has led to efficient degradation of the simplest substances—phenol and naphthalene. The content of these compounds in 2020 was not elevated compared to the standards for industrial wastelands. The three- and four-ring hydrocarbons were degraded at a lower intensity. Based on the mean decrease in content after 5-year enhanced natural attenuation, the compounds can be arranged in the following order: phenols > naphthalene > phenanthrene > fluoranthene > benzo(a)anthracene > chrysene > anthracene.

A geoid for the Australian capital territory

1997 ◽  
Vol 42 (1) ◽  
pp. 25-32
Author(s):  
Kevin A. Freund ◽  
Jim Steed ◽  
A.H.W. Kearsley
Keyword(s):  
Australian Capital Territory ◽  
Australian Capital

Pollen Taphonomy in a Canyon Stream

1987 ◽  
Vol 28 (3) ◽  
pp. 393-406 ◽  
Author(s):  
Patricia L. Fall
Keyword(s):  
Surface Soil ◽  
Pollen Grains ◽  
Close Correlation ◽  
Soil Samples ◽  
Alluvial Deposits ◽  
Modern Pollen ◽  
Pollen Types ◽  
Pollen Rain ◽  
Arid Steppe ◽  
Turbulent Water

AbstractSurface soil samples from the forested Chuska Mountains to the arid steppe of the Chinle Valley, Northeastern Arizona, show close correlation between modern pollen rain and vegetation. In contrast, modern alluvium is dominated by Pinus pollen throughout the canyon; it reflects neither the surrounding floodplain nor plateau vegetation. Pollen in surface soils is deposited by wind; pollen grains in alluvium are deposited by a stream as sedimentary particles. Clay-size particles correlate significantly with Pinus, Quercus, and Populus pollen. These pollen types settle, as clay does, in slack water. Chenopodiaceae-Amaranthus, Artemisia, other Tubuliflorae, and indeterminate pollen types correlate with sand-size particles, and are deposited by more turbulent water. Fluctuating pollen frequencies in alluvial deposits are related to sedimentology and do not reflect the local or regional vegetation where the sediments were deposited. Alluvial pollen is unreliable for reconstruction of paleoenvironments.

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