Evidence for muramic acid in soil

1970 ◽  
Vol 16 (5) ◽  
pp. 299-304 ◽  
Author(s):  
W. N. Millar ◽  
L. E. Casida Jr.

Evidence indicative of the presence of muramic acid in soil was demonstrated. Muramic acid values ranging from 0 to 150 μg/g dry weight of soil were obtained for 33 different soil samples. Comparisons of these values with the muramic acid contents of laboratory-grown microbial cultures revealed that the soil muramic acid levels are about 100- to 1000-fold greater than can be accounted for by a platable bacterial population in soil, but are compatible with other estimates of total bacterial soil numbers. It was suggested that a muramic acid analysis of soil might provide an estimate of its total bacterial population.

2011 ◽  
Vol 3 (5) ◽  
pp. 37-42
Author(s):  
Renata Mikalauskienė ◽  
Donatas Butkus ◽  
Ingrida Pliopaitė Bataitienė

The present article describes changes in specific activities and fluctuations in the ratio of natural 40K and artificial 137Cs radionuclides in soil samples taken from different places of Lithuanian territory. The samples of soil have been selected from the districts polluted after the accident in Chernobyl nuclear plant performing nuclear testing operations. The study has established the main physical and chemical properties of soil samples and their impact on the concentration of 40K activities. 137Cs/40K specific activities in soil have been observed under the dry weight of the sample that varied from 0.0034 to 0.0240. The results of the study could be used for establishing and estimating 137Csand 40K transfer in the system “soil-plant”. Santrauka Straipsnyje nagrinėjama gamtinės (40K) ir dirbtinės (137Cs) kilmės radionuklidų savitųjų aktyvumų ir jų santykio kaita skirtinguose Lietuvos teritorijos dirvožemiuose. Dirvožemio mėginiai parinkti iš vietovių, kurios buvo labiau užterštos po Černobylio atominės elektrinės avarijos ir buvusių branduolinių bandymų. Tyrimo metu nustatytos pagrindinės fizinės cheminės dirvožemio savybės ir jų poveikis 40K aktyvumų koncentracijai. 137Csir 40K savitieji aktyvumai dirvožemyje tirti esant sausam mėginio svoriui. 137Cs savitieji aktyvumai sausame dirvožemyje svyravo nuo 1,1±1,0 iki 14,3±0,9 Bq/kg, o 40K savitieji aktyvumai – nuo 326±29 iki 740±15 Bq/kg. 137Csir 40K savitųjų aktyvumų santykis skirtingų vietovių dirvožemiuose kito nuo 0,0034 iki 0,0240 Bq/kg. Tyrimo rezultatai gali būti panaudoti, nustatant ir įvertinant 137Csir 40K pernašą sistemoje dirvožemis–augalai.


Weed Science ◽  
1968 ◽  
Vol 16 (4) ◽  
pp. 470-473 ◽  
Author(s):  
B. G. Tweedy ◽  
Nikki Turner ◽  
Miriam Achituv

Soil samples with and without a past history of dimethyl-2,3,5,6-tetrachloroterephthalate (DCPA) treatment were obtained from New York. A third sample was obtained from a field in Colorado where DCPA had been ineffective as a herbicide. The populations of bacteria and actinomycetes in these soils were determined and the actinomycetes were more prevalent in the samples with previous DCPA treatment than in untreated samples. Subsequent treatment resulted in an increase in actinomycete population and little change in bacterial population. In pure culture and in soils, the addition of DCPA had no adverse effect upon microbial growth, and several microorganisms appeared to utilize the herbicide as a carbon source. Two degradation products were methyl-2,3,5,6-tetrachloroterephthalate and 2,3,5,6-tetrachloroterethalic acid.


2018 ◽  
Vol 250 ◽  
pp. 01008
Author(s):  
Tuan Noor Hasanah Tuan Ismail ◽  
Siti Aimi Nadia Mohd Yusoff ◽  
Ismail Bakar ◽  
Devapriya Chitral Wijeyesekera ◽  
Adnan Zainorabidin ◽  
...  

Soils at many sites do not always have enough strength to bear the structures constructed over them and some of the soil may need to be stabilized in order to improve their geotechnical properties. In this paper, routine laboratory tests were critically carried out to investigate the efficacy of lignin in improving the strength behaviour of the soils. Two different soil samples (laterite and kaolin) were studied and mixed with different proportions of lignin (2% and 5% of dry weight of soil), respectively. Unconfined Compressive Strength (UCS) characteristics evaluated in this study were done on samples at their maximum dry density and optimum moisture content (obtained from compaction tests). The UCS tests on all the specimens were carried out after 0, 7, 15, 21 and 30 days of controlled curing. The research results showed that the addition of lignin into kaolin reduced its maximum dry density while giving progressively higher optimum moisture content. Contrarily, with the laterite soil, both maximum dry density and optimum moisture content simultaneously increased when lignin was added into the soils. The UCS results showed that the the stabilized laterite with 2% lignin continued to gain strength significantly at a fairly steady rate after 7 days. Unfortunately, lignin did not show a significant effect in kaolin.


1930 ◽  
Vol 20 (4) ◽  
pp. 550-559 ◽  
Author(s):  
T. Gibson

The decomposition of urea has been investigated in 59 soil samples of extremely varied character. Urea was decomposed readily in all and very rapidly in most of the samples.In mountain and heath soils the decomposition was generally active, especially in soil tests. Strongly acid peat samples (pH. 3·1 to 3·3) decomposed from 0·44 to 0·86 per cent, of their own dry weights of urea in 24 hours at 22° to 23° C.In solution and soil tests samples from permanent pastures produced a more rapid decomposition than those from cultivated land. In soil tests with pasture samples quantities of urea as large as 1 per cent, of the dry weight of soil were converted to ammonia in 24 hours at 22° to 23° C. Fertile arable soils produced a relatively slow decomposition in soil tests.


2017 ◽  
Author(s):  
Ali Khatibi ◽  
Sharareh Pourebrahim ◽  
Mazlin Mokhtar

Abstract. In this study, in the city of Karaj five classes of land use-cover including residential, agriculture, rangeland, forest and barren areas were considered and randomly in each class a total of 20 points were selected and vegetation and soil samples were taken. In plant samples, the amount of carbon sequestration was determined by calculating the amount of organic carbon by dry weight and in soil samples, the amount of carbon sequestration was determined by using Walleky and Black method, too. For each area, the average value of carbon sequestration of samples was introduced as carbon sequestration index of that class. Average values for each category were determined as an indicator of carbon sequestration of that class and then by using the DINAMICA EGO software a simulation was conducted using cellular automata approach to simulate changes in the classes of land use-cover in the city of Karaj. Finally, by using carbon sequestration index and the results of the simulation, changes in carbon sequestration in each class were calculated. On this basis, it was found that in the 15-year period from 2014 to 2029, not considering the residential class as the effective use of carbon sequestration, the greatest amount of carbon sequestration was found in the agricultural class and the lowest carbon sequestration was found in barren area. Also, agriculture class will be faced with the huge reduction of carbon sequestration, because of expansion of the residential area.


2020 ◽  
Vol 83 (5) ◽  
pp. 821-828
Author(s):  
JUNE TEICHMANN ◽  
PUSHPINDER KAUR LITT ◽  
MANAN SHARMA ◽  
ESMOND NYARKO ◽  
KALMIA E. KNIEL

ABSTRACT Salmonella enterica subsp. enterica serovar Newport is a bacterial foodborne pathogen isolated from several environmental reservoirs on the Delmarva Peninsula and has been associated with several produce-related outbreaks. However, little is known about specific interactions between Salmonella Newport and soil amendments used as fertilizers. The purpose of this study was to determine Salmonella Newport persistence and resuscitation in raw poultry litter (PLR), a common biological soil amendment, and in soils containing poultry litter–based (heat-treated poultry pellets [HTPP]) or chemical fertilizer (urea [U]) amendments to provide equivalent levels of nitrogen to the soil. Inoculated samples were stored in a growth chamber and irrigated regularly over 4 weeks. Soil samples were collected every week for 4 weeks to determine moisture content and surviving Salmonella Newport populations (log CFU per gram dry weight). Data were analyzed by using a one-way analysis of variance and Student's t test. The PLR supported significantly higher (5.07 log CFU/g dry weight [gdw]) populations of Salmonella Newport than HTPP only (1.70 log CFU/gdw). However, PLR-amended (PLRA) soil (2.5 log CFU/gdw) samples had significantly (P < 0.05) lower Salmonella Newport populations compared with HTPP-amended (4.5 log CFU/gdw) and U-amended (4.0 log CFU/gdw) soil samples. The effect of irrigation on Salmonella Newport population levels in PLRA soils was significant, and in a comparative study, the overall increase in the pathogen levels in U-amended soil (mean = 1.12 log CFU/gdw) was significantly greater than that in PLRA soil (mean = 0.54 log CFU/gdw), whereas that in HTPP-amended soil (0.80 log CFU/gdw) was not significantly different from PLRA soil. HIGHLIGHTS


1954 ◽  
Vol 5 (4) ◽  
pp. 702 ◽  
Author(s):  
HR Angell

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.


2009 ◽  
Vol 6 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Abida Begum ◽  
M. Ramaiah ◽  
Harikrishna ◽  
Irfanulla Khan ◽  
K. Veena

Assessment of heavy metal content in litchens and soil samples from various localities of Hosur Road, Bangalore south was undertaken. Topsoil samples (0-10 cm) were taken at various locations, the metals analysed were Cr, Pb, Fe, Zn, Ni and Cu. The geoaccumulation index of these metals in the soils under study residential areas indicated that they are uncontaminated with Ni, Zn, and Fe and moderately contaminated with Cr and Pb. In Industrial areas and traffic junctions the concentration of Fe, Pb and Ni was maximum. Heavy metal accumulation in few prominent lichens of some localities was analysed. Cr and Pb were maximum inChrysothrix candelaris(L.) Laundon, at the gardens of Madiwala and Silk Board junction with 95.29 and 623.95 µg g–1dry weight respectively. Fe and Cu were maximum inBulbothrix isidiza(Nyl.). Hale andPyxine petricolaNyl at Central Prison campus and Kendriya Sadan campus with 22721 and 338.12 µg g–1dry weight respectively,Lecanora perplexaBrodo at Infosis and Wipro Campus, electronic city have 531.5 and 634 µg g–1dry weight of Zn. While Ni and Fe were maximum in Arthopyreniaceae at Shanti Niketan of MICO Limited with 1100 and 23200 µg g–1dry weight respectively.


2018 ◽  
Vol 7 (4) ◽  
pp. 81
Author(s):  
Abdulrahman Aldaood ◽  
Amina Khalil ◽  
Ibrahim Alkiki ◽  
Madyan Alsaffar

This research work study the influence of cyclic wetting and drying on free swell potential of untreated and lime treated expansive clayey soils. Such a study is required to understand the behavior of these soils during wet-dry cycles. Two expansive soils (a polwhite bentonite and a kaolinite) with different plasticity indexes were used in this study. The soil samples were treated with different lime content in the order of (3, 5 and 7% by the dry weight of soil). The lime treated soil samples were cured at 20ºC for 28 and 180 days. The untreated and lime treated soil samples were subjected to four wet-dry cycles. Free swell potential and cracks propagation were studied during lime addition and wet-dry cycles. Results showed that, the free swell potential of untreated soil samples; in general; decreased with increasing wet-dry cycles, and all of the soil samples reached equilibrium after the second cycle. While the cracks propagation increased with these cycles, especially of bentonite soil samples. Larger cracks propagation has been observed in the bentonite soil samples. Lime addition enhanced the free swell potential values of  the two expansive soils and there was a drastic decrease in free swelling potential and cracks propagation of these soils. The beneficial effect of lime treatment to control the swelling values was partly lost by the first wet–dry cycles, and the free swell potential increased at the subsequent cycles.


2004 ◽  
Vol 28 (4) ◽  
pp. 547-551 ◽  
Author(s):  
Carlos Cardoso Machado ◽  
Reginaldo Sérgio Pereira ◽  
Dario Cardoso de Lima ◽  
Carla Ribeiro Machado e Portugal ◽  
José Maurício Machado Pires ◽  
...  

The objective of the present study was to evaluate the effects of industrial solid waste (whitewash mud) on geotechnical properties considering the following engineering parameters: California Bearing Ratio (CBR), Atterberg limits and Permeability test. Seven soil samples derived from Alagoinhas, Bahia - Brazil, were classified by the Transportation Research Board (TRB) system. Two were selected as having a great geotecnical potential classified as A-3 (0) and A-2-4 (0), whitewash mud contents 10%, 15%, 20% and 25% dry weight and medium compaction effort were studied in the laboratory testing program. The results indicated the soil denominated good gravel as being the most promising one, when stabilized with whitewash mud, reaching the best results with the dosage of 20 and 25% of whitewash mud.


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