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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Influence of secondary transformation index of peat-muck soils on the content of selected metals

100%
Boguta P., Sokołowska Z., Bowanko G.
Acta Agrophysica
|
2011
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tom 18
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nr 2[193]
The main aim of the study was the determination of the content of selected metal ions in soils originating from Polesie Lubelskie and Biebrza River Region, as well as an attempt at relating the results obtained to the degree of secondary transformation of studied soils. All the soils belonged to peat-muck soils and differed from each other in their secondary transformation index. The study included analyses of the content of potassium, calcium, magnesium and manganese with the use of absorption atomic spectroscopy for the determination of the concentration of those metals. At the next stage of the study, relationships between the secondary transformation index of peat-muck soils and selected metal contents were examined. Weak linear relationships were found for the secondary transformation index and the content of calcium, manganese and potassium. A more complex situation was observed for the relation of magnesium ions. The lack of a straight-line trend could be explained in this case by the effect of chemical processes occurring in particular classes of mucks transformation on magnesium ion binding.
2
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Influence of the state of peat mass secondary transformation and date of sowing on darnel [Lolium perenne L.] emergencies

72%
Gawlik J., Harkot W.
Acta Agrophysica
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2001
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tom 52
Influence of the sowing date and state of secondary transformations of moorsh formations on the Lolium perewne seed germination in the condtions of pot xperiments was studied. Peaty moorshes (Zi) and proper moorshes (Z2) with granular structure'taken TrönTTFe peat-moorsh soils at various stages of the moorshing process were used in the present experiment. Two levels of soil moisture were applied. It was found out that the influence of the sowing date on the differentiation of darnel emergencies on the moorsh soils was not big. However, a clear tendency for better germination of the seeds sown in summer than those sown in spring was observed. It was especially visible on the granular moorsh formations (Z3) that were not able to create as favourable water conditions for darnel seed germination and development of seedlings as peat moorshes (Zi) because of poor abilities for water conductivity. The present experiment showed that in order to ensure darnel emergencies on the soils formed of granular moorshes it is necessary to keep their moisture level close to 80% of their full water capacity. Seed germination was influenced more by the kind of moorsh and its moisture level than by the status of secondary transformation of the moorsh mass and sowing date.
3
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Division of differently silted peat formations into classes according to their state of secondary transformations

72%
Gawlik J.
Acta Agrophysica
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2000
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tom 26
Three groups of moorsh formations distinguished on the basis of their ash content were divided into classes according to the state of progress of their secondary transformations. The basis for the division were numerical values of their water-holding capacity index W1. It was found that with the increase of ash content, the threshold value of the W1 index that distinguishes peats without any signs of secondary transformations from the peat formations secondary transformed, i.e., moorshes, also increases. In the moorshes with the lowest ash content (<25%) and weakly silted moorshes (26-50%), the threshold value of the W1 index is 0.35, whereas in the strongly silted moorshes with the mineral part content from 51 to 80%, it is 0.40. Five classes were defined in each of the group of moorshes - the first of them includes moorshes at the initial stage of secondary transformations, and the fifth one totally degraded formations.
4
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Contact angle and surface free energy of selected peat-moorsh soils

72%
Hajnos M.
Acta Agrophysica
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2000
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tom 26
Surface free energy and contact angle for peat-moorsh soils were determined on soil samples consisted of two kinds of moorsh formations, i.e., peaty moorsh (Z1) and proper moorsh (Z3). The samples represented peat soil mass in different state of its secondary transformation, so they essentially differed in values of W1 index. In study a thin-layer (TLW) technique based on Wash- burns equation was used. For this purpose the penetration rate of n-alkanes and diodomethane were measured. If the content of humous compounds in the soil exceeds 40%, wetting rate measurements can only be performed using apolar liquids, such as diiodomethane and alkanes. Polar liquids, on the other hand, such as water or formamide, do not penetrate porous soil layers. This shows that the tested material displays only dispersion-type surface interactions. Therefore, for "mor" and peat soils, the technique of thin-layer wicking with n-octane could only be used to determine the dispersive component . The investigated peat soil no exhibit a polar interactions because the water does not penetrate into yiLW the sample. For the peaty-moorsh soils only dispersive surface free energy components can be determined by the technique of thin-column wicking (TCW). Contact angles can be calculated from the determined dispersive surface free energy components and water surface tension by Young equation. Ranges of water contact angles for peat-moorsh soils are 97.5°<9 <102.0°.
5
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Kinetics of organic matter release at two temperatures from selected peat materials at different state of secondary transformation

58%
Matyka-Sarzynska D., Sokolowska Z., Gawlik J.
Acta Agrophysica
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2000
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tom 26
Laboratory experiments were performed to study the influence of time and temperature on the amount of organic matter released from soil.Samples of six different peat materials that represent: weakly, medium, strongly and very strongly secondary transform peats were submitted to release experiments at 20 and 90°C.Beside time and temperature, the state of secondary transformation of peat material has influenced on the amount of released organic matter. Two shapes of kinetic curves were obtained.
6
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Variable surface charge of selected peat materials as determined from back titration

58%
Matyka-Sarzynska D., Sokolowska Z., Jozefaciuk G.
Acta Agrophysica
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2000
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tom 26
The surface charge studies were conducted on peat materials at various states of the secondary transformation characterized by W1 index. A back titration method for the determination of the variable surface charge was applied and distribution of the apparent surface dissociation constant for investigated soils were determined. In this method the peat suspensions were titrated with 0.1 N NaOH in IN NaCl solution. For weakly and medium secondary peats positive correlation between quality of the surface charge and the W1 index was found. The best correlation appeared between the surface charge and the summary content of fulvic and humic acids. However, for proper moorsh material two populations can be distinguished. For all samples very strongly acidic surface sites are dominant. Furthermore, the average apparent surface dissociation constant values were similar for all peat-moorsh soils.
7
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Influence of the kind of moorsh and the state of its transformation on the germination and growth of Lolium perenne in the pot plant experiment during spring-summer cycle

58%
Gawlik J., Harkot W.
Acta Agrophysica
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2000
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tom 26
The influence of the kind of moorsh and the state of its transformation, as expressed in numerical values of the water absorption index W1, on the germination conditions of Lolium perenne seeds and further growth of young plants have been studied. It was found out that the main factor differentiating these conditions was grain structure of the moorsh mass that determined water conductive properties of the studies soils. The highestnumber of germinated seeds (40-85%) and the best plant growth was observed on peaty moorshes (Z1) of fine fibrous character with fresh humus admixture. Considerably worse conditions for darnel germination and growth (25-50% of germinated seeds) were found on proper fine-grained moorsh (Z3). It was confirmed by a relatively low dty mass yield of plants collected on these soils after completion of the experiment. The highest differentiation of seedlings, and at the same time the poorest germination were found on the proper degraded moorsh with crumble-grained structure with poor conductivity, and on peaty fibrous moorsh that formed a macro-porous layer on the soil surface in the conditions of intensive insolation and high air temperatures. This macro-porous layer efficiently limited capillary rise and evaporation. It was observed that the stale of transformation of moorsh formations expressed with numerical values of the W1 index did not exert any visible influence on the conditions of plant vegetation. The above observation proved that the W1 index is only vaguely connected with the soil conductive properties.
8
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Effects of secondary transformation of peat-moorsh soils on their physical properties

58%
Slawinski C., Sokolowska Z., Walczak R.
Acta Agrophysica
|
2000
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tom 26
Detoriation of water conditions in the peat soils are closely related to the transformations that take place in the structure of organic soil mass. Changes in water relations together with an increased access of air enable various physical, chemical and biological processes to take place. This, in turn, leads to changes in organic soil mass and soil mass transformation into moorsh. The scope of changes and their rate depends also on the properties of the original materials. Amorphic peats are most susceptible to secondary tranformations, whereas fibrous peats undergo moorsing slower. peat formations after secondary transformations have been divided into 5 groupsassuming numerical values of water absorptivity as the basic for the division. This index expresses the ratio between the lowest water absorptivity of a given formation to its absorptivity in the fresh state.The aim of the present work was to evaluate in what way type of moorsh and degree of its secondary transformation influence some of its physical properties, i.e., retention curves and water conductivity, absorption level (wetting) and desorption (drying) of steam as well as its specific surface area. The study object included peaty moorshes and proper moorshs originating from peats formations at various stages of decomposition. The soil material originated from the region of Polesie Lubelskie.
9
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Effect of secondary transformation state of peaty-moorsh soils on adsorption isotherm water vapour

58%
Sokolowska Z., Hajnos M., Matyka-Sarzynska D., Gawlik J.
Acta Agrophysica
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2000
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tom 26
Water vapour adsorption on peat-moorsh soils in various phases of the moorshing process was investigated. The soil material represented two kinds of moorsh: peaty moorsh (Z1) and proper moorsh (Z3) characterizing different classes of peat transformation, i.e., weakly secondary transformed (W1=0.41-0.50), medium secondary transformed (W1=0.51-0.60), strongly secondary transformed (W1=0.61-0.70), very strongly secondary transformed (W1=0,7l-0.80) and completely degraded (W1>0.80). The Brunauer-Emmet and Teller (BET) equation was used to analyse the experimental adsorption results and to calculate the specific surface area from both adsorption and desorplion isotherms. Generally, the values of the specific surface area obtained from desorption isotherms were higher than those obtained from sorption curves. The shape of all curves was similar; i.e., all the curves belonged to the same class of isotherms according to the BE T classification. The values of the correlation coefficient, R, indicated that the BET equation provided a good fit to the experimental data. For all studied samples the BET specific surface area estimated from the sorption isotherm ranged between 250 and 340 m2 g¯1 and between 320-460 m2 ¯1, if the desorption isotherms were used. The average BET specific surface area for the samples of the peaty moorsh (Zi) and the proper moorsh (Z3) were similar. The relationship between surface area and water holding capacity index W1, characterising the state of the secondary transformation was found.
10
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Nitrogen adsorption study of the surface properties of the secondary transformed peat-moorsh soils

58%
Sokolowska Z., Hajnos M., Bowanko G.
Acta Agrophysica
|
2000
|
tom 26
The influence of moorshing processes of peat soils on nitrogen adsorption and on specific surface area was investigated. Soil samples for study were taken from differently moorshified peat-moorsh soils, characterizing by W1 index ranged from 0.44 to 0,82. The samples represented two kinds of moorsh formations, i.e., peaty moorsh (Z1) and propert moorsh (Z3). Nitrogen adsorption measurements at 77 K were used for determining the surface area and pore volume. The Brunauer-Emmett-Teller (BET) method was used as the standard procedure for determination of the surface area. The adsorption and desorption isotherms of N2 on peat-muck soils at 77 K exhibited similar shape and all belonged to the type II, according to BET classification. The adsorption increased in the series of the soil samples Nos 11<1<13<12 and 10<5<6<8 for the peaty moorsh (Z1) and for the proper moorsh (Z3), respectively. The above series agreed with the changes of the index of the secondary transfbrmation,W1, except for the samples Nos 12 and 5. The nitrogen-BET specific surface area of soil samples ranged from 2.45 to 4.90 m2 g¯1, and no direct relation between the surface area and the index of the secondary transformation, W1, was found. When soil samples are first grouped into the classes Z1 and Z3, and then, for each group, arranged according to the value of the index W1, the relationship between W1 and the specific surface area became more visible. Generally, for the proper moorsh (Z3), an increase of the nitrogen-BET surface area and a decrease of the pore volume were correlated with the increase of the W1 index (except for the samples Nos 8 and 5). In the case of the peaty moorsh (Z1) a decrease of the nitrogen-BET surface area and an increase of the pore volume were connected with the increase of the W1 index, (except for the samples Nos 12 and 13).
11

Relation between the water capacity index and selected surface properties of peat-muck soils

58%
Sokolowska Z., Matyka-Sarzynska D., Hajnos M., Gawlik J.
Polish Journal of Soil Science
|
2003
|
tom 36
|
nr 1
The studies were conducted on peat materials at various states of secondary transformation characterised by the W1 index. The positive correlation between the specific surface area calculated from water vapour adsorption and the water holding capacity index W1 was found. However, no direct relationship between the specific surface area determined from nitrogen adsorption was noticed. The variable surface charge increases with the value of W1 for all samples. The soils investigated are divided into two groups. For investigated soils only the dispersive surface free energy component can be determined. Contact angles were calculated using the component of the surface free energy and water surface tension determined earlier by the Young equation.
12
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Ocena zawartosci utlenialnej frakcji wegla w glebach torfowo-murszowych o roznym stopniu wtornych przeobrazen

44%
Matyka-Sarzynska D., Sokolowska Z.
Acta Agrophysica
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2000
|
tom 38
149-156
Badania przeprowadzono na 14 murszach o różnym stopniu wtórnych przeobrażeń. Dla każdej gleby określono ilość węgla ulegającego w ciągu 2 godzin utlenieniu 0,005 M roztworem KMnO4 o PH= 2,5. Generalnie obserwuje się wpływ stopnia wtórnego przeobrażenia na zawartość podatnej na utlenianie substancji organicznej, zwłaszcza dla utworów silnie i bardzo silnie wtórnie przeobrażonych. Ponadto otrzymane wyniki przeanalizowano uwzględniając zawartości kwasów fulwowych i huminowych w badanych murszach. Dla gleb o współczynniku W1>0.60 wraz ze wzrostem udziału w glebie kwasów fulwowych rośnie zawartość frakcji węgla utlenialnej KMnO4.
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