The chemical properties and enzymatic activity of the surface soil horizon were compared between an organic farm (OF) (crop rotation with legume plants, fertilisation with manure) and a conventional ...farm (CF) (simplified crop rotation, mineral fertilisation, chemical crop protection products). In the years 2001-2017 on the OF (near the village of Juchowo, northern Poland), a reduced tillage system (ploughless) was used, while plough cultivation was used on a CF located in its immediate vicinity. The parameters used to assess the properties of soils were: particle size composition, pH, total organic carbon (TOC) and total nitrogen (TN), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). The activity of dehydrogenases (DEH), catalase (CAT), alkaline phosphatase (AlP) and acid phosphatase (AcP) and the content of easily extractable glomalin-related soil protein (EEGRSP) were also determined. Sixteen years of soil use in accordance with ecological principles significantly increased the average content of TOC, NT, DOC and DON. Soil samples rich in TOC and DOC showed significantly higher DEH and AcP activity, and EEGRSP content. Statistical analysis showed that the activity of DEH, AlP and CAT in the soil was significantly higher for the OF than for the conventional cultivation system. Limiting soil cultivation procedures on the OF improved the balance of soil organic matter (SOM) and pH value, and significantly increased the content of EEGRSP as compared to the cultivation system used on the CF.
The application of water-borne pressure-sensitive adhesives (PSA) based on acrylics is increasing in a variety of industrial areas. The have been used for manufacturing of double sided and carrier ...free mounting tapes, splicing tapes, marking and sign films, self-adhesive labels, packaging tapes, protective films and diverse high quality medical materials. Nano-sized inorganic fillers can modify diverse adhesive and self-adhesive coating properties such as tack, peel adhesion, shear strength at 20°C and 70°C, and removability Amorphous synthetic silica nanoparticles in form of water dispersions: Ludox PX-30 (30 wt.% silica stabilizing with counter ion sodium), Ludox PT-40 (40 wt.% silica stabilizing with counter ion sodium), Ludox PT-40AS (40 wt.% silica stabilizing with counter ion ammonium), and Ludox PW-50 (50 wt.% silica stabilizing with counter ion sodium) (from Grace) in concentrations between 1 and 5wt.% were used for modifying of water-born pressure-sensitive adhesive acrylics: Acronal 052, Acronal CR 516 (both BASF) and Plextol D273 (Synthomer) properties. It has been found in this study that the nano-technologically reinforced system containing of Acronal 052 and amorphous silica Ludox PX-30 showed a great enhancement in tack, peel adhesion and shear strength. In this paper we evaluate the performance of Acronal 052 modified with amorphous silica Ludox PX-30.
The aim of the study was to determine the effect of soil management systems of Brunic Arenosols on total content of organic carbon and its fraction susceptible to oxidation in comparison with soils ...under forests. Samples for study were taken from the humus horizon at sites located in forests and soils from little mid-forest cultivated fields (hunting plots). The agrotechnical treatments increased the content of plant-available forms of P, K and Mg in the soils of most hunting plots in comparison to forest soils. In the arable horizon of the hunting plots there was found a varied total content of organic carbon and its fraction susceptible to oxidation. Cultivation of soil in hunting plots caused a decrease in content of total organic carbon as well as its labile and non-labile fraction. To evaluate the carbon transformation in the soil of the cultivated plots against the forest (reference soil), the Carbon Management Index (CMI) was used. The decay rate of soil organic matter in a natural forest was lower than in the agricultural fields. A long-term tillage of Brunic Arenosols contributed to the degradation of the pool of organic carbon in sandy-textured soil.
To assess the soil quality of Phaeozems and Luvisols from Kujawy region (Kujawy-Pomerania Province, Poland), the soil quality indicators such as: content of organic matter and nutrients, as well as ...bulk density were used. The soils showed similar inherent properties (soil texture, depth to parent material, type of clay) and management practices (tillage, crop rotation, nutrient application). The following properties were determined: bulk density, grain size composition, exchangeable acidity, concentration of available forms of potassium, phosphorus and magnesium, and the content of total organic carbon (TOC) and nitrogen (Nt). The amounts of dissolved organic carbon (DOC) and dissolved nitrogen (DN) were measured in the solution obtained after extraction with 0.004 M CaCl
. The stock of TOC
, Nt
and DOC
, and DN
were calculated. The total organic carbon content in surface horizon of Phaeozems was significant higher (13.9-20.1 g·kg-1) than in Ap horizon of Luvisols (8.3-11.0 g·kg
), which is a consequence of their origin. The stock of organic carbon in Ap horizon fell within 5.89 to 8.49 kg·m
in Phaeozems and 3.80 to 4.81 kg·m
in Luvisols. Although Phaeozems demonstrated a significant higher content of TOC, as compared with Luvisols, the amount of dissolved organic carbon was similar in both soil types, which points to a higher share of DOC in the total organic carbon content in Luvisols (up to 17.5% in Et horizon). The amounts of dissolved organic carbon and dissolved nitrogen and their stock do not depend on the type of soils if the management practices are similar.
The aim of the research was to assess the effect of long-term application of different doses of nitrogen fertilizers with or without manure to changes in the total organic carbon content, total ...nitrogen content, evaluation of dissolved organic carbon content and the value of absorbance coefficient (A4/6) in sandy loam soil. The base of research was the long-term field experiment, established in 1979 at the Wierzchucinek Experimental Station close to Bydgoszcz city - Poland. The experiment was carried out in the three-course crop rotation, potato, rye, rye in randomized split-plot design. The experimental treatments were four levels of N fertilizers in 0, 47, 93, and 140 kg∙ha-1∙yr-1 (N0, N1, N2, N3) as a 1st factor of experiment, and the same doses of N fertilizers with farmyard manure application (30 t∙ha-1) as a 2nd factor. After 36 years of experiment the content of total organic carbon was 26% lower and the content of total nitrogen 13% higher compared to the values determined before the experiment foundation (1979). The consequence of changes in the content of organic carbon and total nitrogen, are changes in the ratio of organic carbon content and total nitrogen content. It was noticed that the use of manure and different nitrogen doses resulted in a decrease of organic carbon content and total nitrogen content value. After application of different nitrogen doses, organic carbon content ranged from 122.4 to 152.2 mg∙kg-1. The same nitrogen doses applied simultaneously with farmyard manure increased the organic carbon content, which ranged from 133.5 to 166.7 mg∙kg-1. The changes of the organic carbon content did not effect on percentage of this fraction in the total organic carbon. Percentage of organic carbon content in total organic carbon content was on averaged 1.6%. After the application of different nitrogen doses, humic acids of analyzed soils were characterized by lower average value of A4/6 (5.4). However, the application of nitrogen doses with manure brought a higher - 6.3 - A4/6 value. Farmyard manure application caused the formation of humic acids of lower molecular weight and a low humification degree.
Purpose
The paper describes rhizospheric (Rs) and non-rhizospheric (nRs) soil to demonstrate the zone of the plant root impact on physical and chemical properties of the soil. The effects of the ...process accompanying the transformations of organic matter into humic substances in the rhizosphere of “common dandelion”
Taraxacum officinale
have been determined, and the properties of humic acids (HAs) were described. The importance of iron and clay minerals for the formation of a stable and water-resistant soil structure has been emphasized.
Materials and methods
The laboratory analysis involved determination of basic physical and chemical soil properties: texture, pH, cation exchange capacity (CEC), electrical conductivity, and content of total organic carbon (TOC) and dissolved organic carbon (DOC) and quality of humic substances: optical properties of HAs and its separation into hydrophilic (HIL) and hydrophobic (HOB) fractions, speciation of iron, glomalin operationally described as an easily extractable glomalin-related soil protein (EE-GRSP), and soil aggregate stability (SAS) of six size classes of soil aggregates.
Results and discussion
The Rs was reported with a higher TOC and DOC content (measured in the CaCl
2
extracts), however not significantly. The HAs isolated from Rs revealed a significantly higher content of humic substances at its initial decomposition stage, as compared with nRs. A significantly higher concentration of EE-GRSP was noted in the aggregates of the rhizospheric zone (mean 1.14 g kg
−1
) than in the aggregates collected from root-free soil (mean 0.94 g kg
−1
). There was noted the highest mean share of 1–3 mm soil aggregates in Rs as well as in nRs, respectively 44.4 and 38.3%. The soil material both in Rs and in nRs contained high amounts of exchangeable Ca
2+
, and smectite is the predominant clay mineral. It was favorable for the accumulation of organic carbon and for the formation of good soil physical condition (tilth). Higher but insignificant SAS values were observed for Rs (mean SAS = 95.6%) than for nRs (mean SAS = 93.9%).
Conclusions
The studies confirm the role of common dandelion roots in the process of organic carbon accumulation in rhizospheric zone and a favorable effect on the mechanism of the formation of water-resistant aggregates. Higher values of SAS for the Rs were affected by the content of TOC, DOC, exchangeable Ca
2+
and the concentration of EE-GRSP, and, less considerably, the content of Fe and clay minerals.
The present study describes properties of humic substances of the Fluvisols (the Lower Vistula, Poland). Fluvisols under agricultural management (arable soil and grassland) were sampled from the ...surface horizon 50, 200, 600, and 900 m from the Vistula River. The content of carbon in the fractions of humic acids (C
HAs
), fulvic acids (C
FAs
), and humins (C
HUMIN
) as well as the content of dissolved organic carbon (DOC) were assayed. The organic matter of the soils that were sampled 200 m from the river demonstrated a lowest share of the humic acids (HAs) and fulvic acids (FAs). The percentage share of the hydrophilic fractions (HIL) in the HAs and, as a result the value of the HIL/ΣHOB ratio, increased with the distance from the riverbed. The HAs of the soils located further from the riverbed had a higher degree of humification compared to the HAs of the soils that were sampled 50 and 200 m away. Based on the research results, it was determined that the properties of HAs can be used to evaluate the effect of flood events, their location, and scope on the transformation of the organic matter in fluvial sediments.
The aim of the research was to assess the effect of long-term application of different doses of nitrogen fertilizers with or without manure to changes in the total organic carbon content, total ...nitrogen content, evaluation of dissolved organic carbon content and the value of absorbance coefficient (A.sub.4/6) in sandy loam soil. The base of research was the long-term field experiment, established in 1979 at the Wierzchucinek Experimental Station close to Bydgoszcz city - Poland. The experiment was carried out in the three-course crop rotation, potato, rye, rye in randomized split-plot design. The experimental treatments were four levels of N fertilizers in 0, 47, 93, and 140 kg*ha.sup.-1 * yr.sup.-1 (N.sub.0, N.sub.1, N.sub.2, N.sub.2) as a 1st factor of experiment, and the same doses of N fertilizers with farmyard manure application (30 t*ha.sup.-1) as a 2nd factor. After 36 years of experiment the content of total organic carbon was 26% lower and the content of total nitrogen 13% higher compared to the values determined before the experiment foundation (1979). The consequence of changes in the content of organic carbon and total nitrogen, are changes in the ratio of organic carbon content and total nitrogen content. It was noticed that the use of manure and different nitrogen doses resulted in a decrease of organic carbon content and total nitrogen content value. After application of different nitrogen doses, organic carbon content ranged from 122.4 to 152.2 mg*kg.sup.-1. The same nitrogen doses applied simultaneously with farmyard manure increased the organic carbon content, which ranged from 133.5 to 166.7 mg*kg.sup.-1. The changes of the organic carbon content did not effect on percentage of this fraction in the total organic carbon. Percentage of organic carbon content in total organic carbon content was on averaged 1.6%. After the application of different nitrogen doses, humic acids of analyzed soils were characterized by lower average value of A.sub.4/6 (5.4). However, the application of nitrogen doses with manure brought a higher - 6.3 - A.sub.4/6 value. Farmyard manure application caused the formation of humic acids of lower molecular weight and a low humification degree.
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